####018008828#### FXUS65 KGJT 040520 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 1120 PM MDT Fri May 3 2024 .KEY MESSAGES... - A system will brush the northern tier of eastern Utah and western Colorado today, bringing a few valley rain and mountain snow showers through this evening. Minor accumulations are expected with little to no impacts. - Scattered showers and isolated thunderstorms are possible late Saturday mainly in the mountains. Elsewhere expect warmer and dry conditions. - A strong system is expected on Sunday and Monday. It will bring widespread precipitation and strong winds. A High Wind Watch has been issued for much of eastern Utah and far western Colorado Sunday morning through Sunday evening. && .SHORT TERM /THROUGH SATURDAY NIGHT/... Issued at 348 PM MDT Fri May 3 2024 The cold front and upper level jet associated with the shortwave trough moving across the north is evident both on satellite and radar across the eastern Tavaputs in northeast Utah into northwest Colorado across the Flattops and into the northern Park Range. Some light showers are occurring in Craig and Hayden with rain at Hayden and rain flipping over to snow at Craig. Roads remain wet to dry according to webcams in that neck of the woods with trace accumulations on the grassy surfaces north of Craig where it's actively snowing. All in all, impacts remain minimal with maybe 2 to 5 inches of snow at the higher elevations of the Park Range but other than that, roads are expected to remain wet. Much different story along and south of I-70 where dry conditions are evident as relative humidity is in the teens with winds gusting in the 30s and 40s. Some locally higher gusts are occurring due to presence of virga showers but these gusty winds combined with the low relative humidities is leading to critical fire weather conditions at times. Temperatures today along and south of I-70 are sitting at 4 to 8 degrees above normal with areas north of I-70 cooler at 5 to 10 degrees below normal. Showers should come to an end early this evening as this shortwave over the north exits and the jet and cold front lift northward as a warm front by Saturday. Strong WAA is expected to take place Saturday afternoon with high temperatures warming by about 5 degrees along and south of I-70 with a warm up of 10 to 15 degrees from today across the north. Highs on Saturday will be 5 to 10 degrees above normal across most of the area. In this southwest flow, we will still see some breezy conditions, but winds are expected to be less than today as the jet lifts north and shortwave ridging takes place. The hi-res CAMs are indicating a bit of instability Saturday afternoon with a weak shortwave moving through the southwest flow, skirting the divide, so isolated to scattered thunderstorms are possible along the western Colorado mountains mainly along the divide. The gradient tightens Saturday night into Sunday ahead of a strong closed low that will dive southeastward from the PacNW into the Great Basin, settling over Nevada by Sunday morning. More on this in the Long Term discussion below. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 348 PM MDT Fri May 3 2024 By Sunday morning, eastern Utah and western Colorado are expected to be sandwiched between a ridge over the Great Plains and a strong Pacific Low dropping into the Great Basin. Wrapping around the base of this low, an intense southwesterly jet is expected to push into the region on Sunday. Strong winds are expected throughout the column, with 45-60 knots at 700mb and 95-110 knots at 250 mb. 700 mb is roughly the same altitude as some of the highest peaks in eastern Utah and western Colorado, so at a baseline, without factoring in any other daytime boundary layer mixing or virga shower enhancement, mountain locations are looking at least 50-60 mph gusts on Sunday afternoon, with valley locations looking at a baseline of at least 35-45 mph. But of course, we do have to account for those other factors, with strong diabatic heating allowing for deep boundary layer mixing to tap into and bring down the much higher windspeeds aloft, and virga showers breaking out ahead of the approaching cold front. With all these other factors accounted for, another 10-20 mph added onto the baseline makes a reasonable forecast, and is bared out by probabilistic guidance indicating a high probability (>99%) of gusts 45-55 mph in the valleys and 55-65 mph for the mountain regions. Peak gusts into the 60s across the lower elevations and into the 80s at higher elevations will also be possible especially across eastern Utah and far western Colorado zones. Eastern Utah will likely see some of the highest gusts as the jet remains overhead here the longest, providing ample time for deep mixing to tap into the jet and mix down stronger gusts through the day. A High Wind Watch has been issued for all valleys and most mountain areas of eastern Utah, as well as the lower valleys and mountains of far western Colorado where potential and confidence is highest for gusts 55 to 65 mph in those valley zones and gusts to 75 mph in those mountain areas. The High Wind Watch will begin 8 AM Sunday and last through 10 PM. Stay tuned for updates relating to this situation, and if you have outdoor furniture or other objects prone to being disturbed by strong, gusty winds, take the time now to prepare. The strong winds are just the first part of the impacts from this approaching Pacific low. An potent cold front is progged to move through late Sunday into early Monday morning, with substantially colder air moving in behind it. 700mb temperatures on Sunday morning are currently forecast around 4C, and within 24 hours are forecast to drop to nearly -7C. In reflection of this, snow levels will start out on Sunday morning at 9500-10000 feet, and will crash down to 5500-6000 feet by the same time on Monday. Only the highest elevations will see snow for the duration of this system, with most everywhere else beginning with rain showers on Sunday evening. Higher elevation valleys and lower slopes of the mountains will see a changeover to snow as the cold front passes. Current guidance doesn't keep much precipitation around in the post-frontal airmass, with the exception of orographic showers across the northern mountains, so little if any accumulating snow is expected for most locations. The northern and central mountains remain most favored to see the highest QPF, with totals 0.50" to 1.00" still in the forecast from Sunday morning through Monday night. The southern mountains may see 0.25" to 0.50" total through the same period, while the lower elevations can expect 0.25" or less. Most locations will see this all or mostly in the form of rain, although the central and especially northern Colorado mountains above 9000 feet will see a substantial chunk of that QPF in the form of several inches of snow. Travel over mountain passes may be a bit messy on Monday morning. Cold and unsettled northwest flow sets up in the wake of this low, which is forecast to eject into the northern Plains Monday evening. Some wrap around moisture from this low combined with favorable flow will keep light orographic showers going over the northern mountains. General troughiness is expected to linger from Tuesday on through the end of the week, with multiple waves riding the northwesterly to westerly flow over eastern Utah and western Colorado and keeping mountain showers a possibility most afternoons. The cooler air that moves in with the cold front late Sunday into Monday will remain in place through the late week period, with temperatures running 5-10 degrees below normal. That means highs in the 50s to low 60s across the lower elevations, with 30s-40s up high, until Friday when the blended guidance indicates temperatures warming to near normal values. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1120 PM MDT Fri May 3 2024 Overnight, mostly clear to clear skies expected with light winds. Saturday, few to scattered skies on tap with lighter winds. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...High Wind Watch from Sunday morning through Sunday evening for COZ001>003-006-011-017-020-021. UT...High Wind Watch from Sunday morning through Sunday evening for UTZ022-024-025-027>029. && $$ SHORT TERM...MDA LONG TERM...BGB AVIATION...TGJT ####018010485#### FXUS61 KBOX 040521 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 121 AM EDT Sat May 4 2024 .SYNOPSIS... High pressure brings dry weather with cooler onshore breezes through Saturday. A slow-moving frontal boundary brings clouds and rain showers on Sunday into early Monday, along with a period of cooler high temperatures. Though clouds and off and on showers may linger in southeast New England in vicinity of the slowing front, drier weather prevails for most of interior Southern New England. Turning warmer on Tuesday with abundant sunshine, and though temperatures will be significantly cooler near the coast, interior areas could see high temperatures reach near 80 degrees. Our next chance for rain is around midweek. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 740 PM Update: Tranquil early-evening underway across Southern New England, governed by a 1024 mb high pressure area located in the waters east of Ipswich Bay. This high pressure remains generally stationary over at least the next 24 hours, maintaining dry weather but with an increase in cirrus/high clouds as the evening progresses. Used some of the RAP to show a decrease in sky cover for most of the evening, thus pleasant conditions for any Friday evening outdoor plans. However the fly in the ointment arrives by the pre-dawn hrs and mainly in eastern MA, in the form of marine-layer stratus which is evident in satellite imagery over Nova Scotia and the Bay of Fundy. These low clouds should gradually build/spread southwestward through the Gulf of Maine into Cape Cod and the adjacent eastern coastal waters toward daybreak. Think greatest extent of low cloud cover should be restricted to the immediate eastern MA coast, with scattered lower clouds further inland to around central MA/RI by daybreak. Low temps in the low-mid 40s seem on track for now with expectation of generally clear skies for most of the evening, with cooling likely not to be impeded by advancing stream of high clouds. Previous discussion: Good amount of wind shear visible on the satellite this afternoon with mid level clouds moving NE to SW and upper level cirrus moving NW to SE this afternoon. As for those mid clouds, the May sun is helping to increase our breaks of sun but partly cloudy is about the best we can hope for in much of southern New England for the rest of the day. By the overnight hours we'll see some marginal clearing of both mid and high clouds, especially after midnight, but fully clear skies aren't expected. Even so, given the high overhead and calm winds, did lower temps a but to account for some potential to radiate. Lows bottom in the low to mid 40s; right around average for early May. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/... High pressure nudges further south into New England from Nova Scotia bringing continued quiet weather for the first half of the weekend. This means continued cool, moist onshore flow from the northeast so low clouds will be moving in from the northeast while high clouds move in from the southwest. High temperatures won't be too different than Friday, with the warmest spot (the CT valley) in the upper 60s and the coolest spot (eastern MA) in the mid 50s. Cloudcover continues to increase overnight as deeper moisture (PWATs over 1 inch) move into western SNE on SW flow ahead of the approaching system. However, rain should hold off until after 8am. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... Highlights: * Cloudy, cooler with rain on Sunday into early Mon, with continued lighter showers on Mon for southeast New England. * Dry and turning mild on Tue, though cooler onshore flow near the coasts. Spot 80s in the CT Valley? * Next chance for rains around midweek (Wed/Thu), though still unclear which day has the higher rain chances. Details: Sunday and Monday: The 12z suite of guidance continues to come into better congruence regarding our next chance for steadier light rains associated with a passing frontal boundary and a rather disorganized 500 mb trough. Chances for rain increase during the morning in most areas, with the period of greatest rain chances focused during the Sunday afternoon to early Monday morning period as the frontal boundary slowly shifts eastward. With the front becoming parallel to the 500 mb flow with time as we move into the early Monday period, expect lingering rain showers during the morning hrs along the RI/MA South Coast, Cape Cod and the Islands. Further north and west, we should see dry weather but with a mix of clouds and sun. Overall not a soaking rain, but enough to likely put a damper on outdoor plans for many on Sunday, with rain showers lingering into Monday for the southeast New England coastal areas. To that end, model-ensemble probabilistic QPF assessment shows high (70-90%) probs of 24 hr rain totals over a tenth of an inch, but lower to moderate (25-50%) probs for rain amts at or over a half inch. Official forecast has rain amts around a quarter to third of an inch. Expect Sunday to be a cooler day with cloud cover and rains around, with narrower diurnal range in high and low temps. Highs Sunday in the mid 50s, and lows in the upper 40s to near 50. High temps are more challenging on Monday with more clouds south of the Mass Pike and especially near southern coast, with some sunny breaks further north. Highs along the southern coast probably struggle to reach 60, but you don't have to go much further inland before highs reach into the low to mid 70s; with lows in the mid 40s to low 50s. Tuesday: High pressure over interior northern New England governs weather conditions into Southern New England Tuesday, supplying dry weather and mostly sunny conditions. An early look at model forecast soundings in interior MA/CT show potential for temperatures to overachieve guidance with progged deep mixing; with 850 mb temps around +7 to nearly +10C, highs could reach around 80 degrees in the CT Valley with readings well into the 70s eastward into RI and into the MA coastal plain. Northeast flow near the coast will keep temps several degrees cooler than well inland though, in the mid to upper 60s. Very difficult to show that level of granular detail given model-resolution limitations at this forecast time horizon and utilized some of the bias-corrected temperature fields given a similar regime. Did note NBM was advertising some low PoPs in this period for spot showers, but feel this is pretty overdone given progged mixing. Wednesday and Thursday: Though this period offers the next best chance for rain associated with an elongated warm front from low pressure over the Plains states, there is more uncertainty in timing when chances are greatest. Really will need those uncertainties to become more in clearer focus before delving into specifics. Didn't make too many adjustments to NBM in this period, except capped PoPs at the higher end of Chance range (40-50%) given stated timing uncertainties. && .AVIATION /05Z SATURDAY THROUGH WEDNESDAY/... Forecast Confidence Levels: Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 06Z TAF Update: Through 12Z: High confidence. VFR conditions persist through 12Z with light and variable winds becoming more steady out of the east/northeast by sunrise. Today...Moderate confidence MVFR level cloud bases move onshore this morning from the east, but there is a bit of uncertainty with respect to sky cover. Humidity in the low levels is choppy, so coverage may range from SCT to BKN at times. So expect intermittent periods of MVFR ceilings for the first half of the day until the skies fill into BKN/OVC buy mid-afternoon/evening. Steady east/northeast winds from 5 to 10 knots. Tonight...High Confidence MVFR/IFR ceilings return overnight with continued light easterly winds. Winds becoming more east/southeasterly by 12Z Sunday. Tomorrow...High Confidence MVFR borderline IFR ceilings for most of the day tomorrow. Southeast winds becoming more southerly by hte afternoon. KBOS TAF...Moderate Confidence High confidence in MVFR cloud bases, but less confidence in coverage. There may be intermittent periods of SCT/BKN VFR/MVFR ceilings. KBDL TAF...High confidence in TAF. Outlook /Sunday Night through Wednesday/... Saturday Night: Mainly VFR, with local IFR possible. Sunday: Mainly VFR, with local IFR possible. Chance SHRA. Sunday Night: MVFR/IFR conditions possible. SHRA. Monday: Mainly VFR, with local IFR possible. Slight chance SHRA. Monday Night through Tuesday: VFR. Tuesday Night: VFR. Chance SHRA. Wednesday: Mainly VFR, with local MVFR possible. Chance SHRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Marine This evening through Saturday night... High pressure supports fairly calm conditions across the coastal waters through Saturday night. Winds will prevail out of the northeast from 10 to 15 knots with some gusts to 20 knots possible. Seas generally 1 to 3 feet. Outlook /Sunday Night through Wednesday/... Saturday Night: Winds less than 25 kt. Sunday: Winds less than 25 kt. Chance of rain showers. Sunday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Rain showers likely. Monday: Winds less than 25 kt. Seas locally approaching 5 ft. Chance of rain showers. Monday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers. Tuesday: Winds less than 25 kt. Slight chance of rain showers. Tuesday Night through Wednesday: Winds less than 25 kt. Chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...None. && $$ SYNOPSIS...Loconto/BW NEAR TERM...Loconto/BW SHORT TERM...BW LONG TERM...Loconto AVIATION...RM MARINE...Loconto/BW ####018007642#### FXUS63 KABR 040521 AAC AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 1221 AM CDT Sat May 4 2024 .KEY MESSAGES... - A banded rainfall event over the southern/eastern portions of the forecast area will relocate to mainly just the eastern portion of the CWA through late tonight. Rainfall amounts in excess of one half inch can be expected overnight. - High pressure will bring dry and warmer conditions this weekend. - A much larger system looks to affect the region on Monday, with widespread moderate rainfall. The threat for severe weather still appears low at this time (higher across NE/KS/OK), but we will continue to monitor trends. && .UPDATE... Issued at 845 PM CDT Fri May 3 2024 A very favorable set-up for banded precipitation has unfolded (and is ongoing), between strong low to mid-level fronto-forcing and a 100+knot upper level speed maximum. For a while, there were some strong returns showing up within this band of rain, and some of that could have been caused by bright-banding (occurs when the radar assigns too high a reflectivity/rainfall rate to water coated snowflakes falling through the melting layer). Legacy and dual-pol rainfall estimates off the KABR 88D have maxed out at ~2.00-2.50 inches and ~1.50-2.25 inches, respectively. MRMS estimates are lower (more reasonable) ranging from ~0.50-0.75 inches of rainfall along a stretch from northern Hand County through Spink and Clark Counties up into Day County. There's plenty more forcing/lift to be had over the next ~6 hours or so, particularly over northeast South Dakota into west central Minnesota. Perhaps another 0.10 to 0.25 inch of rain could happen along and east of a line from Miller, SD to Wheaton, MN. Low temperatures still look okay for tonight. UPDATE Issued at 647 PM CDT Fri May 3 2024 See below for an aviation forecast discussion for the 00Z TAFs. && .SHORT TERM /THIS EVENING THROUGH SATURDAY NIGHT/... Issued at 315 PM CDT Fri May 3 2024 An upper level trough currently west of the region will track across the Dakotas tonight, with a fairly potent shortwave affecting mainly the eastern part of the CWA. The trough weakens as it exits the area on Saturday, with ridging then building in Saturday night. At the surface, the region is currently situated between a low pressure system over southern Ontario and a low over Colorado. The boundary between these two systems will be the focus for rain late this afternoon and tonight as the aforementioned shortwave moves over the area. Currently seeing some scattered shower activity over mainly the western half of the CWA, but expect this area of rain to become more of a line from southwest to northeast by this evening, generally extending along and east of a line from west central Minnesota to Murdo. The area of rain will then spread eastward tonight. Right now, thunderstorm potential looks to stay south of the CWA, but cannot rule out a stray thunderstorm maybe affecting the southeastern CWA this evening. The highest rainfall amounts are expected along and east of a line from Wheaton, MN to Murdo, where one quarter to one half inch looks to occur. Should a thunderstorm develop, there could be some locally higher amounts. High pressure will settle over the region Saturday and Saturday night, bringing a return to dry conditions. Low temperatures tonight will range from the lower 30s along and west of the Missouri River, to the lower 40s across west central Minnesota. High temperatures on Saturday will be in the upper 50s to mid 60s. Lows Saturday night will be in the mid to upper 30s. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 315 PM CDT Fri May 3 2024 This forecast period begins Sunday morning on a relatively quiet note compared what were anticipating to be another round of active and wet weather through the majority of next week. Upper level ridging will build overhead on Sunday in response to an upper level trough/low moving through the Great Basin and adjacent regions of the western CONUS. Sfc high pressure will be positioned off to our east while low pressure will be situated across the lee of the Rockies and Northern High Plains on Sunday. Southerly low level flow will intensify through the daytime as the pressure gradient tightens. Increasing southerly winds through the day will potentially reach advisory criteria, especially across our western zones. NBM probabilities of seeing max wind gusts greater than or equal to 34kts(40mph) is high(70-100%) along and west of the Missouri Valley. At this point in time, the thinking is that this is a bit on the high category or extreme, so will continue to take a more conservative approach and keep an eye on trends with incoming future guidance data. With a decent amount of sunshine to round out the weekend and dry conditions expected, we should see a nice warm up. 950mb temps are expected to reach about +13C to +19C which translate to highs in the 60s to low 70s across the forecast area. Unfortunately, all good things have to end sometime and we'll see the pattern shift quickly by Monday into a more active and wet one. The aforementioned upper low is progged by both deterministic and ensemble guidance to track northeastward out of the Rockies into portions of the Northern High Plains and Northern Plains early next week. This system looks to be rather vigorous on Monday as sfc low will track into the Central Plains and shift northward into our region. Severe weather parameters looks best across the Central Plains and south of our region by Monday afternoon and evening, however we can't totally rule out some stronger activity in parts of our area. As of right now, our forecast area is just outside of the northern fringe of the better instability. MUCAPE values on the order of about 300-500 j/kg is possible, especially across our southern zones with far more higher values to the south in parts of NE and KS. We'll just have to keep track of the trends over the next couple days to see if there's any movement farther north with these better ingredients. The upper flow pattern remains unsettled at least through the middle of next week and perhaps even through the end of this period. Guidance progs a stagnant pattern locally with the upper low or trough meandering and spinning just off to our northwest. Multiple s/w's in southwest flow aloft over our region will likely keep on and off shower chances persisting through the week. Underneath the more extensive cloud cover that anticipated, temperatures will be held in check close to normal but probably falling short of average for this time of year. Daytime values in the 50s and 60s can be expected with overnight temperatures in the 40s. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1220 AM CDT Sat May 4 2024 Terminals KABR,KATY,KPIR,KMBG VFR conditions are forecast throughout the TAF valid period at KPIR, KMBG and KABR. KATY could see a couple of hours of MVFR cigs and/or MVFR/IFR visbies in rain between now and 12Z. Beyond that, KATY should see prevailing conditions become VFR prior to 18Z. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Dorn SHORT TERM...Parkin LONG TERM...Vipond AVIATION...Wise ####018005219#### FXUS65 KCYS 040521 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 1121 PM MDT Fri May 3 2024 .KEY MESSAGES... - A cold front will move through the region by this evening with another round of shower activity in the mountains. Snow levels will remain above 6500 feet. - Breezy to windy, and cooler weather expected for Monday through Wednesday, with isolated to scattered late day showers and thunderstorms. && .SHORT TERM /THROUGH SATURDAY NIGHT/... Issued at 159 PM MDT Fri May 3 2024 As the cold front continues to move east across southeast Wyoming and western Nebraska, we saw a weaker dryline develop ahead of it stretching from near Cheyenne to Alliance with southerly winds and dewpoints in the upper 40s ahead of it, and north to northwest winds and dewpoints in the 20s to low 30s behind it. A line of thunderstorms developed along it with pockets of 40 knots of shear and CAPE values near 1000 J/kg, but it was quickly undercut by the approaching cold front and died out nearly as fast as it developed. Rawlins saw some moderate to heavy snow showers this morning, and while they are very slowly moving east, they will likely not impact areas east of Interstate-25, producing very little precipitation between the Laramie Valley and the Interstate-25 corridor, including Cheyenne. The primary impacts to areas between the Laramie Valley and the Interstate-25 corridor for the rest of the day will be occasional light rain showers and snow showers possible above 6500 feet, but mainly strong gusty winds with wind gusts 35 to 45 mph possible and colder temperatures tonight. Saturday the trough moves off to the east as a ridge approaches southeast Wyoming and western Nebraska bringing high temperatures in the 50s to low 60s with clear skies. Winds will likely be light with south to southeast wind gusts 20 to 30 mph possible across the High Plains. Overall a pleasant, cool Saturday expected. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 159 PM MDT Fri May 3 2024 Warm day Sunday will transition to a prolonged windy and slightly cooler pattern as a storm system slow churns across Intermountain West beginning Monday and persisting into Wednesday. Looking like there is a chance for elevated winds with intermittent periods of high winds to impact the wind prone areas and much of the I-25 corridor and areas across the Nebraska Panhandle. The long term forecast will begin with a nice day on tap for Sunday as upper level ridging settles across the area allowing for 700mb temperatures to climb into the 7-11C which will translate to afternoon high temperatures climbing into the upper 60s to mid 70s for locations east of the Laramie Range and into the Nebraska Panhandle. Ahead of the next storm system increasing clouds and low level moisture will lead to the development of some high elevation snow showers across Carbon county and the Sierra Madres. Not expecting much in the way of impactful accumulation with these snow showers. A combination of a slow moving and strengthening storm system moving to our south and some lee troughing will be the catalysts from a prolonged period of windy conditions across much of SE Wyoming and the Nebraska Panhandle. Not much change regarding the NBM probabilities as they continue to show a period from Monday through Wednesday night where a large swath of SE Wyoming and the Nebraska Panhandle of seeing a (>80%) chance of seeing wind gusts greater than 40 mph Monday through Wednesday with lower intermittent probabilities of periodically seeing wind gusts up to high wind criteria (>58 mph). The wind prones should see more consistent wind gusts above high wind criteria so if we can stay underneath the jet energy aloft and keep those gradients tight then I'd expect we may begin to issue high wind highlights in the coming forecast updates. The extent of the winds and magnitude as stated above will be the track of the low pressure system to our south as a more southerly shift would pull the bulk of the high winds aloft further south into Colorado and this cut down on both the magnitude and duration of the wind threat. This track to the south would also pull the wrap around moisture out of northern Wyoming and southern South Dakota and shift it more into our area increasing the precipitation chances heading into next week. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1120 PM MDT Fri May 3 2024 VFR conditions currently across area terminals as upper level clouds continue to move off towards the east, giving way to mostly clear skies. Latest GOES Nighttime Microphysics RGB does show lingering low clouds mainly near southeast WY terminals that could persist through the early morning hours. Gusty winds will return Saturday afternoon, generally out of the south. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...LEG LONG TERM...AW AVIATION...MB ####018007483#### FXUS64 KFWD 040514 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 1214 AM CDT Sat May 4 2024 ...New Short Term, Aviation... .SHORT TERM... /NEW/ /Overnight through Sunday/ Convection is waning across the region tonight as surface based inhibition increases. A cluster of showers and a few storms continue to the south of Waco at this hour, but this activity should diminish over the next hour or so. The remainder of the night should be quiet with light winds and humid conditions. Some patchy fog may develop later tonight into the early morning hours on Saturday. The active weather pattern will continue with a cold front currently across southwest Kansas expected to move through Oklahoma overnight and approaching North Texas Saturday morning. Synoptic scale forcing for ascent may be negligible during this time, but forcing along the front itself may be sufficient for scattered showers/storms to develop earlier than they did on Friday. This activity is most likely to occur across our northwest counties and generally north of I-20 into the early afternoon. We'll have some 30-40% PoPs to account for this activity while our central TX counties will likely remain dry. It's a little unclear whether or not the front will actually make it down into our area through midday with a consensus of the guidance suggesting that it'll get hung up to our north in response to an approaching upstream shortwave. This shortwave is evident on water vapor imagery approaching northern Baja California at this hour. Meanwhile, either an outflow boundary or just a general backing of the low level flow ahead of the front will likely lead to increased low level moisture convergence across the I-20 corridor through the afternoon. This will support isolated/scattered storm development through late afternoon, especially from the Metroplex westward. Meanwhile, thunderstorms will increase in coverage across West Texas and become severe near the intersection of the southward moving front and dryline late this afternoon. This activity will likely evolve into one or more clusters of thunderstorms and spread eastward into North Texas late Saturday night as stronger forcing for ascent from the aforementioned shortwave overspreads the Southern Plains. While there will certainly be some potential for severe weather, especially across our western counties, widespread heavy rainfall may result in additional flooding issues across parts of the region. Latest HREF guidance shows a large swath of 2-3 inches of rain through late Saturday night across our southwest counties, the majority of which falls in about 3 hours. This may necessitate a westward expansion of the flood watch. We'll coordinate this over the next several hours. Showers and thunderstorms will overspread much of the region late Saturday night and continue to move eastward into early Sunday morning, tapering off from west to east through the day. Additional thunderstorm development may occur late Sunday afternoon across our central and southeast counties as the front stalls in wake of the departing shortwave. Dunn && .LONG TERM... /Issued 258 PM CDT Fri May 3 2024/ /Saturday Night Onward/ An active weather pattern will continue Saturday night as a shortwave embedded in the subtropical jet lifts northeast across North and Central Texas. Thunderstorms will likely be ongoing at the start of the period across the Big Country, and will spread east across the region overnight into Sunday morning. A wind and hail threat may accompany these storms across the western half of the region Saturday evening, but convection will be weakening Saturday night while moving into a less favorable environment. Despite the severity or lack thereof, the presence of a quasi- stationary surface boundary will maintain a threat for more heavy rain and flooding. This threat will be highest over Central Texas where heavy rains have already occurred, and where the front will most likely be located (and is currently exacerbating the ongoing flooding across the Brazos Valley and Southeast Texas). A Flood Watch has hence been issued through around midday Sunday for those Central Texas Counties who have experienced multiple rounds of heavy rain over the past several days. Convection will move out during the morning hours Sunday, making for an overall decent day with highs mainly in the 70s. There may be a few rogue showers that pop up in the afternoon but those should be few and far between. Attention will then turn to a larger scale upstream trough, which will cross the Rockies Sunday night, then lift northeast through the Plains on Monday. Most of the ascent associated with this system will remain to our north, but we will still likely have isolated dryline-induced convection Monday afternoon and evening. Coverage may be low due to the presence of a capping inversion, but we will otherwise have a warm and unstable environment in place, and any storms which develop could become severe. The passing of the shortwave will send a cold front south into the area Tuesday night. After a quiet Tuesday, the front will again provide a focus for convection starting Wednesday, as a longwave trough produces cyclonic flow overhead for the mid to late week period. Scattered showers and storms should develop in the afternoon and evening hours Wednesday and Thursday. Not all will receive rain, but just about any of the area could see a shower or storm. By Friday, the front will have sagged well south of the I-20 corridor, unfortunately focusing convection across the saturated Central and Southeast Texas. The front and trough will both shift southeast of the region on Saturday, providing dry weather and overall nice conditions in time for Mother's Day weekend. 30 && .AVIATION... /NEW/ /6Z TAFs/ VFR cigs generally prevail in the wake of convection earlier this evening but conditions will again deteriorate overnight with MVFR cigs expected by morning across most of North and Central Texas. We'll be watching a front slide southward through the morning hours into the D10 airspace. This may be sufficient for a few isolated storms to develop earlier than they did on Friday. Better storm chances will arrive late Saturday night as another complex of storms is expected to track across North Texas through the overnight hours. Dunn && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 69 80 67 79 68 / 30 40 100 30 20 Waco 65 80 66 78 67 / 40 30 100 40 20 Paris 68 80 65 75 65 / 20 40 70 80 20 Denton 67 80 64 77 66 / 30 40 100 30 20 McKinney 68 80 66 76 67 / 30 40 90 40 20 Dallas 69 82 67 79 68 / 30 40 90 30 20 Terrell 65 80 67 78 67 / 20 40 90 40 20 Corsicana 66 82 68 79 69 / 20 30 90 40 20 Temple 68 81 67 79 68 / 40 30 90 40 20 Mineral Wells 59 79 64 79 67 / 40 40 100 10 20 && .FWD WATCHES/WARNINGS/ADVISORIES... Flood Watch through Sunday afternoon for TXZ135-146>148-160>162- 174-175. && $$ ####018005678#### FXUS64 KTSA 040522 AFDTSA Area Forecast Discussion National Weather Service Tulsa OK 1222 AM CDT Sat May 4 2024 ...New AVIATION... .SHORT TERM... (The rest of tonight) Issued at 956 PM CDT Fri May 3 2024 Showers and thunderstorms moving north into central Oklahoma at this time will likely dissipate or remain west of our area. The current forecast is on track with the MCS currently across western Kansas moving east southeast into parts of northeast Oklahoma late tonight or early Saturday morning. The only change to the forecast this evening is to remove the low pops in parts of western Arkansas tonight. && .LONG TERM... (Tomorrow through Friday) Issued at 233 PM CDT Fri May 3 2024 A complex of storms is expected to develop across Kansas this evening and progress east southeastward overnight tonight. the leading edge of this MCS will begin to nudge into parts of northeast Oklahoma by early Saturday morning with some gusty winds possible along the leading edge along with heavy rainfall. Overall, the complex should be in a weakening state as it moves through northeast Oklahoma throughout the rest of the morning hours. Still locally heavy downpours will be possible with the stronger cores with high moisture content over the region. The rest of the day Saturday will see lower chances (20-40%) for some lingering showers and storms in the wake of the decaying MCS and whatever outflow boundaries are leftover from that. Heading into Sunday, increasing chances for widespread showers and storms are expected as a shortwave trough lifts northeastward out of central Texas and tracks across eastern Oklahoma during the day. The severe threat will remain low during this time, but isolated severe potential will exists with the more persistent updrafts. The main threat will be locally heavy rainfall on top of already very saturated soils. Rainfall throughout the last week has been in the 5 to 7 inch range for a good chunk of eastern Oklahoma and parts of western Arkansas. Additional rainfall of 1 to 2 inches is likely for much of the area with locally higher amounts quickly causing concern for flash flooding and flooding of urban or low lying areas due to excessive runoff. It won't take much for flooding to occur, so have opted to issue a Flood Watch for the entire forecast area given the saturated conditions and already high rivers and streams. The unsettled pattern will continue into next week as an upper low ejects out into the Central to Northern Plains and meanders for several days. This will allow for moderately strong westerly to southwesterly flow aloft to develop over the Southern Plains and last through much of the week. Concurrently, a surface cold front will drop southeastward into Kansas and become stalled, while a dryline extend southward into Oklahoma and Texas. These areas will serve as the focus for daily shower and storm chances for much of eastern Oklahoma and western Arkansas. The strong flow aloft combined with a warm and moist boundary layer will support severe potential with any storms that develop. Monday will be the first day to watch in the period as the main upper trough swings into the Plains. Best storm chances will exist across northern Oklahoma closer to the large scale ascent as an expanding elevated mixed layer (EML) spread over the Southern Plains likely capping convection further south along the dryline. Still, a couple storms will be possible along the dryline with all severe hazards possible. Details will continue to come into better focus as Monday gets closer. The surface front is progged to drop down into eastern Oklahoma on Wednesday, which would enhance shower and storm chances Wednesday afternoon as well. Again, all severe hazards appear possible at this time. Everyday next week through at least Thursday, looks like a day to watch as the environment will be supportive of severe potential each day. Continue to monitor the latest forecasts. Bowlan && .AVIATION... (06Z TAFS) Issued at 1217 AM CDT Sat May 4 2024 Ongoing storms over north central OK are likely to weaken as they spread toward NE OK terminals, however additional showers and storms may expand later this morning along the trailing cold front. The forecast will account for this possibility with at least isolated to scattered convection spreading eastward through the early to late morning hours. Periodic MVFR ceilings are also possible generally area wide late tonight through the morning. Storm chances continue through the day with the focus being the remnant outflow / weak cold front. More organized and widespread convection is expected into the region this evening into tomorrow night. && .PRELIMINARY POINT TEMPS/POPS... TUL 60 73 62 81 / 60 80 10 40 FSM 65 76 64 83 / 50 90 20 30 MLC 63 75 63 81 / 70 90 10 30 BVO 55 72 58 80 / 50 80 10 40 FYV 60 74 59 81 / 50 90 30 40 BYV 60 72 60 80 / 40 80 30 30 MKO 62 72 62 80 / 60 90 20 30 MIO 58 71 60 80 / 40 80 20 40 F10 61 72 62 80 / 70 90 10 30 HHW 65 75 64 79 / 60 90 10 30 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...Flood Watch from 7 AM CDT this morning through Sunday evening for OKZ049-053>076. AR...Flood Watch from 7 AM CDT this morning through Sunday evening for ARZ001-002-010-011-019-020-029. && $$ SHORT TERM...05 LONG TERM....04 AVIATION...07 ####018011539#### FXUS63 KIND 040522 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 122 AM EDT Sat May 4 2024 .KEY MESSAGES... - Potential for patchy fog and low clouds late tonight and early Saturday. - Isolated to scattered showers and storms again on Saturday. - Multiple chances for showers and storms throughout most of the forecast period, with continued above normal temperatures. - Potential for severe weather during the middle of next week, highest chances Tuesday evening and Wednesday night. && .FORECAST UPDATE... Issued at 949 PM EDT Fri May 3 2024 Forecast is in good shape this evening. Isolated showers near the old boundary across central Indiana have continued to weaken with loss of heating. Kept some slight chance PoPs for the next hour or so to account for any stubborn showers that remain. (Thunder was removed with an earlier update). Patchy fog will remain a possibility overnight tonight. Across the southeast, lingering low level moisture and light winds could lead to patchy fog formation. In the northwest, where drier air will have moved in, partial clearing and light winds might compensate for the drier air and still allow some patchy fog to form. Otherwise, adjusted sky cover as needed based on latest trends seen on satellite. Low temperatures look good, so just adjusted hourly temps as needed. && .SHORT TERM (This evening through Saturday)... Issued at 256 PM EDT Fri May 3 2024 Damp and mainly cloudy afternoon in progress across the forecast area as a diffuse frontal boundary lingers over the southeast half of central Indiana. Have seen some breaks in the lower stratocu develop behind the boundary but tend to fill right back in with an abundance of low level moisture lingering. Scattered showers have redeveloped over southeast counties over the last hour or two. 18Z temperatures ranged from the upper 60s to mid 70s. Today marks the beginning of a more unsettled regime setting up over the Ohio Valley for the next several days and not expected to reach its zenith until the early to middle part of next week. However the presence of lingering low level moisture at least across parts of the region and the remnant boundary likely to settle near the Ohio River tonight will bring at least a periodic threat for isolated to scattered convection through late day Saturday and eventually beyond. Through Tonight Expect any isolated showers or thunder will focus in the vicinity of the boundary and deepest portion of the moisture plume...focused across the southeast half of the forecast area. The current ACARS sounding highlights weak instability levels that have increased slightly courtesy of diurnal heating despite the clouds. It should be noted however that the actual primary windshift and dewpoint boundary lags back to the northwest from the front...and that could aid in additional isolated development early this evening focused back near the I-70 corridor. Will hold onto isolated pops for a short period as far northwest as a Terre Haute-Indy Metro-Muncie line as a result. Could certainly see a few rumbles of thunder but overall any convection over the next few hours will be disorganized and weak in the absence of little if any BL shear and light winds through the lower levels. Broad area of clear skies and dry air noted on current satellite imagery this afternoon back across Wisconsin and northern Illinois associated with a high pressure ridge. This feature will drift east into the Great Lakes tonight and while the bulk of the subsidence and dry air will remain to the north of the forecast area...this will sway enough influence locally to allow for clearing skies late tonight focused across the northern Wabash Valley. Further south across the forecast area...the dewpoint boundary will shift south a bit before stalling overnight with much of the forecast area south of I-70 remaining at 60 degree dewpoints or higher. While any threat for a shower is minimal overnight considering little forcing aloft and negligible instability...the presence of the deeper moisture will keep the potential for lower stratus across the southern half of the forecast area and may also bring patchy fog into play prior to daybreak. While the air will be slightly drier in northwest counties...there is an increased potential for some fog formation in these areas as well with skies set to clear late. Saturday The aforementioned surface ridge will move northeast away from the Great Lakes on Saturday...leaving a residual axis of drier air extending southwest from lower Michigan into eastern Missouri. This will be slowly gobbled up through the course of the day between the deeper moisture plume focused across the Ohio Valley and our southern counties and a frontal boundary tracking through the Missouri Valley. The veering of low level winds to easterly and eventually southeasterly by the afternoon will enable the deeper moisture to advance back to the northwest across central Indiana and interact with an increasingly unstable airmass as CAPE values climb to 1000-2000 j/kg. While overall forcing aloft and shear remain weak...the combination of the instability and moisture will be enough to generate scattered convection again on Saturday with the best focus once again over the southeast half of the forecast area. Storms will be of pulse intensity and may see a few stronger cells that can throw out localized higher wind gusts. Otherwise... lightning and brief/localized heavy rainfall will be the primary impacts to outdoor activities on Saturday from any convection. Temps...lows will fall back into the middle 50s tonight across the northern Wabash Valley but most of the rest of the forecast area will remain closer to 60. Low level thermals support highs rising into the upper 70s and lower 80s across much of central Indiana Saturday with the warmest reading likely to be across western portions of the forecast area where convective coverage will be lower and more sunshine will be realized. && .LONG TERM (Saturday night through Friday)... Issued at 256 PM EDT Fri May 3 2024 We're looking at a fairly active long range with precipitation chances nearly every day. Severe weather is not expected through the weekend, though this may change by early to mid next week. SYNOPTIC OVERVIEW The upper-level flow pattern across North America is rather simple. A long ridge axis stretches up the eastern seaboard and a broad trough exists over the northern Plains. Along the Mexican border, a zonal but fairly fast subtropical jet extends into the Gulf. Further west, over the Pacific Ocean, another trough can be found diving southward out of the Gulf of Alaska. It's this Pacific trough that may become the driving factor for active weather next week. Through the weekend, however, we'll be dealing with occasional showers and thunderstorms as a few impulses aloft pass by. The first, covered in the short term, is more a part of the northern jet while a second lifts northeast from the subtropical jet Sunday into Monday. With no strong push of continental air, a warm and buoyant air mass is likely to be in place through the weekend and into next week. As such, any system passing by should have access to enough instability for convective precipitation. In fact, model soundings Sunday-Monday show essentially a moist adiabatic profile. Low LCLs with high freezing levels may promote more contribution from warm rain processes. Available moisture is high (PWAT over 1.5 inches) and deep, so rainfall may be quite efficient at times. This of course depends on how much forcing there is for convection, and some model uncertainty remains regarding where exactly the vort max tracks. By Monday afternoon, the Pacific trough should be ejecting into the Plains in a highly amplified manner. Guidance shows the trough occluding quickly, with upper-level flow regaining a more zonal orientation Tuesday and Wednesday. The occluded low meanders over the northern Plains for a few days, with vort maxes occasionally rotating around and progressing eastward over the Midwest. Guidance is in good agreement regarding the larger-scale pattern but disagrees with the smaller features (vort maxes). The placement and timing of these vort maxes may play a critical role determining severe potential Tuesday and Wednesday. FORECAST CONFIDENCE COnfidence is good with the large-scale pattern, but decreases with regards to sensible weather. The primary driver of this uncertainty is variations in track/timing of various vort maxes. Additionally, convective regimes can have a cascading affect on subsequent convective evolution...so uncertainty can be high even if the larger- scale pattern is more certain. That being said, a few things can still be said about our potential for severe weather / flooding next week. As mentioned before, ensemble guidance is in good agreement with the larger pattern. Additionally, NAEFS/ECMWF situational awareness tables show anomalous moisture through this weekend and much of next week. Deterministic guidance, while showing more disagreement between individual models, is still useful in visualizing how this moisture interacts with passing waves. Periodic surges of richer/deeper moisture advect northward ahead of each wave, signifying potential for heavy rainfall in addition to severe weather through the period. Regarding severe weather, CSU machine learning and CIPS analogs have been honing in on the Tuesday-Wednesday period over our region. It remains a rather broad area, and favorable synoptic conditions (Occasional synoptic forcing, instability, shear) add confidence to these signals. It's difficult to downscale things any further at this range since the final outcome will likely rely on features not yet resolvable. Still, the potential exists for severe weather along with heavy rainfall next week. Stay tuned for updates. && .AVIATION (06Z TAF Issuance)... Issued at 122 AM EDT Sat May 4 2024 Impacts: - MVFR ceilings/visibilities for at least brief periods at all sites late tonight through daybreak. - Low chance for isolated convection Saturday. Discussion: As skies clear from west to east overnight, expect some fog and possibly low ceilings to develop at all sites for at least brief periods. Will carry prevailing MVFR at all outlying sites (IFR at BMG, which has already developed MVFR fog), and TEMPO MVFR at IND. These conditions may persist in some areas into mid morning before returning to VFR. There will be a low chance for showers and isolated storms today, but too low for inclusion in the TAF at this time. Winds will shift significantly through the period, beginning northeasterly and becoming southerly/southwesterly late in the period. Sustained winds will remain below 10KT throughout. && .IND WATCHES/WARNINGS/ADVISORIES...None. && $$ UPDATE...50 SHORT TERM...Ryan LONG TERM...Eckhoff AVIATION...Nield