####018006078#### FXUS64 KMOB 031735 AFDMOB Area Forecast Discussion National Weather Service Mobile AL 1235 PM CDT Fri May 3 2024 ...New AVIATION, NEAR TERM... .AVIATION... (18Z TAFS) Issued at 1235 PM CDT Fri May 3 2024 VFR conditions will prevail through much of the forecast period. Winds will remain from the south and may gust at times through the afternoon. Isolated thunderstorms are also possible; however, confidence is too low to add mention in the TAF and amendments may become necessary this afternoon. Otherwise, winds will diminish overnight. There may be some lower visibilities early Saturday morning and MVFR conditions are forecast but these may need to be lowered. /73 && .NEAR TERM... (Now through Saturday) Issued at 454 AM CDT Fri May 3 2024 The more widespread high cloud cover that we noted in yesterday mornings discussion did indeed increase over the area, and as expected has limited widespread dense fog development across the region so far this morning. These higher clouds are moving east across the area, but beginning to clear somewhat over our MS counties. Some patchy light fog is expected across the area through around 9 AM this morning, but the only locations where any dense fog may briefly develop will be over our western zones where the high clouds are thinning. At this time we don't anticipate that we will need a Dense Fog Advisory for any portion of our area this morning as any dense fog that may develop will probably be somewhat localized and brief in nature. Models do indicate that the mid/high cloud cover will not be as thick or widespread across the region tonight however, and there is a better signal for the potential return of more widespread dense fog late tonight into early Saturday morning. Otherwise, the forecast area remains between an upper ridge along the east coast and troughing over much of the western CONUS, maintaining a southwest to west upper level flow across our area. At the surface, high pressure off the southeast coast will ridge back west into our area and keep a south to southeasterly low level flow over the area through the next couple of days. Combined with daytime heating, weak ripples in the flow aloft may provide enough forcing for isolated to scattered afternoon thunderstorms both today and Saturday, primarily over the western and northern portions of our forecast area. These storms will generally be short-lived given the influence of the ridge. Coverage of showers and storms may be a tad higher on Saturday due to greater available moisture as southerly flow persists, but PoPs should be no more than about 30 percent either day. For both days, activity should diminish with the loss of daytime heating. Daytime high temperatures will continue to range from the mid to upper 80s inland, to the low to mid 80s coastal, both today and Saturday, although there may be a few low 90s over interior locations on Saturday. Lows tonight will mainly be in the middle 60s across most of the area, but a few lower 70s possible along the immediate coast and barrier islands. DS/12 SHORT and LONG TERM... (Saturday Night through Thursday) Issued at 454 AM CDT Fri May 3 2024 A general zonal to, at times, northwesterly flow pattern aloft is expected through the extended period as upper ridging begins to build over the Gulf and a few embedded, weak shortwaves move overhead. At the surface, large high pressure over the western Atlantic remains as the dominant feature, keeping our region under a persistent southerly flow through the entire period. Daytime heating, in combination with weak forcing from one of the shortwaves aloft, and ample moisture in place from the persistent southerly winds at the surface, should allow for isolated to scattered showers and storms to develop, primarily over interior areas during the afternoon and early evening hours on Sunday. Weak shear in place will help to keep convection disorganized and pulse- like in nature, typical of what we see during a general summertime pattern. As is the case for this type of convection, cannot rule out one or two stronger storms that would be capable of producing gusty downdraft winds, mainly as a result from outflow and sea breeze boundary collisions. Rain chances begin to lower on Monday and are out of the forecast by midweek as the upper ridge axis begins to build northward into our area. With the ridge building, very warm, summer-like temperatures are expected across the region, especially as we get into the middle of next week. Highs will top out in the mid to upper 80s through Tuesday, increasing to the upper 80s to low 90s by Wednesday and Thursday. In fact, heat indices by Thursday may climb into the upper 90s for several interior spots. Lows through Monday night will generally range from the mid to upper 60s inland to the low 70s along the coast. Lows moderate further by midweek with low to mid 70s expected by Wednesday night. A moderate risk of rip currents is expected through, at least, the middle part of the week. /96 && .PRELIMINARY POINT TEMPS/POPS... Mobile 69 86 67 86 69 85 70 86 / 10 20 0 10 0 10 0 0 Pensacola 70 83 69 84 71 83 72 84 / 10 10 0 10 0 10 0 0 Destin 70 82 70 82 72 83 72 82 / 10 10 0 10 0 10 0 0 Evergreen 66 89 65 89 65 88 66 89 / 10 30 10 20 10 10 0 10 Waynesboro 66 88 65 88 65 89 68 89 / 20 30 10 30 10 20 0 10 Camden 66 87 66 88 65 88 67 89 / 20 30 20 30 20 20 0 10 Crestview 64 89 64 89 65 88 66 88 / 10 20 10 20 0 10 0 0 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...None. FL...None. MS...None. GM...None. && $$ This product is also available on the web at: www.weather.gov/mob ####018008225#### FXUS64 KEWX 031737 AFDEWX Area Forecast Discussion National Weather Service Austin/San Antonio TX 1237 PM CDT Fri May 3 2024 ...New AVIATION... .UPDATE... Issued at 1129 AM CDT Fri May 3 2024 Patchy fog is lingering a little longer than we had previously anticipated over the eastern half of the CWA. We've updated the forecast to reflect this. Otherwise, it looks to be in good shape. Ongoing convection just east of our area may spread back to the west during the next few hours. Then the focus will shift to the west where the dryline and higher terrain will become active later this afternoon. && .SHORT TERM... (Today through Saturday) Issued at 329 AM CDT Fri May 3 2024 Early morning storms continue along the Highway 77 corridor with a strong storm now exiting northern Fayette county. Light showers are also noted farther west along portions of I-35 and the Hill Country. Elsewhere, patchy fog is in place for most areas outside of the Rio Grande plains. Hi-res models generally show convection will continue for a few more hours early this morning, then gradually decrease in coverage. KEWX VAD wind profile does show roughly 20-25kt southeasterly flow in the lower levels. This along with very moist air characterized by surface dewpoints in the lower to mid 70s is helping to aid convection. For today, expect plenty of cloud cover and humid conditions over the region. Highs today will range from the mid 90s out west along the Rio Grande where some afternoon clearing will be realized. Farther east into the Hill Country and I-35 corridor, highs should stay in the 80s. We will keep rain chances in the forecast today as widely scattered to scattered showers and storms will develop as the lower levels continue to heat. For the late afternoon and evening hours, attention will turn to west Texas as the dryline becomes active. In addition, we should see some convection develop over the Serranias del Burro mountains of Mexico. A good amount of the 00Z hi- res convective allowing models show clusters of storms shifting eastward into the Rio Grande plains, with perhaps a line of storms moving into the southern Edwards Plateau and western Hill Country. Whether or not these storms can make it farther east through the remainder of the Hill Country and I-35 corridor is still uncertain. For now, we have raised rain chances considerably over the NBM for the Rio Grande plains, southern Edwards Plateau and western Hill Country as confidence for convection is higher across these locations. Rain chances may need to be raised farther east across the remainder of the Hill Country and I-35 corridor pending the next suite of hi-res model data. SPC has placed areas generally along and west of the I-35/I-37 corridors in a Marginal Risk (level 1 of 5) for severe weather. Large hail and damaging winds are the main severe weather threats at this time. In addition, locally heavy rainfall is likely, and this may lead to localized flooding in areas that have seen recent rains. Another round of storms will be possible on Saturday afternoon, with the the latest severe weather outlook from the Storm Prediction Center placing areas along and north of a Del Rio to San Antonio to Giddings line in a Marginal Risk (level 1 of 5) for severe weather. A cold front may move into portions of north and central Texas late Saturday and this may provide a focus for shower and thunderstorm development. We will also need to watch for locally heavy rainfall, especially if the cold front or a strong outflow boundary drops southward into the region. && .LONG TERM... (Saturday night through Thursday) Issued at 329 AM CDT Fri May 3 2024 A shortwave disturbance moves through West TX Saturday and generates upscaled convection over West Central and North TX for Saturday evening. Our Hill Country counties are on the southern periphery of this feature, and as we have seen from the Wednesday storm activity, will benefit from the best rain chances for Saturday night. Outflow boundaries will likely lead to locally higher PoPs in the eastern Hill Country and Austin metro area after midnight and into much of Sunday. Additional weak shortwave energy could continue to generate more widely scattered or isolated convection across most areas through Sunday evening. QPF amounts could favor more heavy rainfall mentioning across the north, but not enough areas have endured truly soaked soil conditions for there to be a FFA concern this far out. Farther south or along and south of Highway 90, lower rain chances are expected and overall QPF is minuscule when compared to the rainfall potential along and north of I-10. That said, a discrete strong to severe storm or two forming over southern counties could end up dropping a quick 1-2 inches over isolated spots Throughout the period Saturday night through Sunday night. Appropriately, the national centers have deemed our severe weather and heavy rainfall threats to be "marginal", but areas of "slight" for both categories exist to the north and east, so a possible escalation to the higher threat could evolve as we get closer to the time periods. Sunday night the fetch of shortwave activity appears to fizzle out as a vigorous upper trough cuts across the Central Rockies into the Central Plains. Models have trended more humid and mostly cloudy for Monday with still a relatively deep layer of Gulf moisture. Thus have followed the trends to believe there could be a few showers or sprinkles as the cap takes hold aloft. The drier and more stable pattern in the mid levels should bring our first taste of summer heat for Tuesday through Thursday. The GFS was especially hard-hitting with a short-lived heat wave covering western and central counties in this period, but both GFS and ECM are trending toward less mixing of this drier air aloft mixing down. As it stands, we still see a good chance of triple digit heat along the Rio Grande through the mid-week period, but central and eastern counties are a bit less certain on the temperature range. Thus, will state vaguely that highs in the 90s are most likely each day. && .AVIATION... (18Z TAFS) Issued at 1224 PM CDT Fri May 3 2024 It's a bad flying day in Austin and San Antonio. IFR/LIFR conditions are still hanging around. It doesn't look like there will be a lot of improvement this afternoon. Ceilings should get to MVFR this afternoon and maybe briefly to VFR at AUS. Ceilings should lower again starting this evening dropping to IFR for the late evening and overnight. There is a small chance for showers and thunderstorms this evening with better chances at AUS, but too low to include in the TAF. Ceilings should finally get back to VFR Saturday afternoon. At DRT clouds have scattered out and they will be VFR through the afternoon and early evening. There is a chance for showers and thunderstorms this afternoon and evening with the better chances during the evening. MVFR ceilings will develop during the evening and to IFR overnight. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 70 86 70 82 / 20 20 50 60 Austin Bergstrom Intl Airport 70 85 69 82 / 20 20 50 60 New Braunfels Muni Airport 71 89 71 84 / 20 20 40 50 Burnet Muni Airport 69 83 69 80 / 20 30 60 60 Del Rio Intl Airport 74 91 73 87 / 50 30 50 50 Georgetown Muni Airport 69 83 68 80 / 20 30 50 60 Hondo Muni Airport 70 88 69 83 / 20 20 50 60 San Marcos Muni Airport 70 87 69 83 / 20 20 40 60 La Grange - Fayette Regional 72 86 72 82 / 10 10 30 50 San Antonio Intl Airport 71 87 71 83 / 20 20 40 50 Stinson Muni Airport 72 89 72 85 / 20 20 40 60 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term...Platt Long-Term...18 Update/Aviation...05 ####018009525#### FXUS66 KPDT 031737 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1037 AM PDT Fri May 3 2024 Updated Aviation Discussion .AVIATION...18Z TAFS...VFR conditions for today with currently high clouds at most sites, except for KPDT/KALW having clear skies. Cloud coverage will increase starting this afternoon into tonight/Saturday morning. KPDT might have winds gusting up to 24kts tonight as the low off OR coast pushes a cold front over PacNW. This will also bring rain showers into KDLS/KRDM/KBDN/KYKM Saturday morning as well. Winds will be less than 10kts, but will increase for KPDT/KALW this evening and overnight. Feaster/97 && .UPDATE...Current radar and infrared satellite imagery showing dry and clear conditions. However, there are still some lingering stratus that continues to dissipate over the Southern Blue Mountains and the John-Day Basin. Significant cloud cover is pushing inland ahead of the next robust weather system that will be passing through the Pacific Northwest over the weekend. Clouds will be increasing today as rain chances slowly extend into the east slopes later this evening. This system will bring with it ample moisture and breezy to windy conditions, with widespread precipitation expected Saturday afternoon through Sunday afternoon. A Winter Weather Advisory has been issued along the east slopes of the Oregon Cascades above 4000 feet beginning 5 AM Saturday as up to 10 inches of snow will be possible. There is also a potential for significant, advisory level snowfall across the John-Day/Ochoco Highlands and the Blue Mountains at elevations above 3500 feet Saturday evening through Sunday afternoon, but this will need to be further analyzed due to uncertainties in system track and strength. The secondary concern over the weekend resides with breezy to windy conditions Saturday evening through Sunday as a significant pressure gradient sets up along the Cascades in the wake of the passing cold front Saturday morning/afternoon. This will lead to wind gusts over the Simcoe Highlands early Sunday morning reaching between 35-45 mph, with these winds returning during the late afternoon and evening hours. These elevated winds will also extend across the northern Blue Mountain foothills, with gusts slowly intensifying and approaching advisory criteria Sunday night. 75 && .PREV DISCUSSION... /issued 452 AM PDT Fri May 3 2024/ SHORT TERM...Today through Sunday...A transitory ridge of high pressure will be passing over the region today. This will provide a mild Spring day with temperatures getting into the low 70s around the Basin and 60s in the mountains. High clouds will begin to increase and spread across the forecast area late today and overnight as the next weather system approaches. This closed upper level low pressure system is dropping SE out of the Gulf of Alaska with the center of the low taking a path into SW Oregon Saturday afternoon then continuing into the Great Basin on Sunday. This will bring the leading edge of a cold front into the Cascades tonight but its eastward progress overnight and into Saturday will be slowed as the low center moves into SW Oregon. Eventually the cold front turns into a deformation band of precipitation Saturday night into Sunday as moisture wraps around the low back across northern Oregon and southern Washington. 48 hour QPF amounts ending 12Z Monday continue to show a very high probability that lower elevations could see .5 - 1.0 inches of precipitation while the eastern mountains and Cascade crest could see 1 - 2 inches of precipitation. This amount of precipitation is expected to cause streams and rivers to rise and peak early next week but remain below flood stages. Snow levels will initially be high Friday night and early Saturday around 6000 to 7000 feet. They will begin to lower Saturday afternoon and night as the low passes south of the forecast area. Central Oregon will see snow levels down to 3500 to 4500 feet Saturday night but remain 4500 to 6000 feet across the rest of the forecast area. This could produce 4 to 10 inches of snow along the Oregon Cascade crest impacting travel over the passes so a Winter Weather Advisory has been issued Saturday morning through Sunday morning. Other concern will be some increasing S-SE winds overnight and Saturday. This will produce some gusty winds over the higher terrain of eastern Oregon and cause some downsloping off of the Blue Mountains along the Foothills. A wind shift back to windy westerly winds is expected to take place late Saturday and continue through Sunday. LONG TERM...Monday through Thursday...Another, weaker weather system will move across the Pacific Northwest on Monday and bring another round of precipitation, mainly to the mountains. However, there will be chances even in the lower elevations Monday afternoon. QPF amounts will be fairly light in most areas. In the mountains QPF will be a bit higher, ranging from 1/4 to 1/2 inch along the crest of the Cascades to around 1/4 inch in the Blues and Wallowas. Most other areas will see only a few hundredths. Precipitation chances will end everywhere except over the mountains by Tuesday morning. Some additional shortwave energy could enhance precipitation chances again Tuesday afternoon, mainly over the eastern Oregon mountains, but overall QPF is expected to be very light...only a few hundredths in most locations. Snow levels start out at 4000 feet or higher on Monday, but drop to between 2500 and 3000 feet by Tuesday morning. So, certainly the precipitation will mix with and change to snow in the higher elevations of the Cascades and Blues, and a few inches are possible along the crests with little elsewhere. The ECMWF EFI focuses on precipitation and snow over the Blue Mountains and nearby foothills with and area of 0.6 to 0.8 on Monday. Also on Monday, there is at least some chance of thunderstorms mainly over the eastern Oregon mountains, as this next systems moves through. CAPE values are expected to be in the 100 to 300 J/KG range, though the best CAPES look to be further southeast. LI values look to be between 0 and -2 degrees C. By Tuesday evening into Wednesday and for the remainder of the period, a ridge will build over the Pacific Northwest. This should bring drier weather and warmer temperatures. A few shwoers over the eastern mountains can't be ruled out on Thursday, but confidence is low (<30%) at this time. Winds will start out quite gusty as a result of the pressure gradient between the departing trough in the Great Basin and higher pressure to the west. WInds will gust 25 to 35 mph and possibly as high as 40 mph in portions of the Columbia Basin, Blue Mountain Foothills, Columbia Gorge. Winds will decrease during the day but remain gusty and become more widespread as the next system approaches. Gusty winds look to continue into Tuesday, with speeds 25 to 35 mph, before decreasing into Wednesday. The ECMWF EFI keys in on the Columbia Basin and Foothills of the Blue Mountains for winds on Monday, with values ranging from 0.6 to 0.8, with a core of 0.8 to 0.9 over the Blue Mountains. The NBM probabilities of wind gusts >= 39 mph on Monday are 70 to 90% across much of the Basin and Blue Mountain Foothills Simcoe Highlands and Cascade Gaps. On Tuesday, the NBM probabilities of wind gusts >=39 mph are 80% plus across much of the Basin, Gorge, Blue Mountain Foothills , Simcoe Highlands, and Kittitas Valley. The probabilities of wind gusts >=47 mph are 50 to 70% across portions of the Columbia Basin, Foothills of the Blue Mountains, Simcoe Highlands and 60-90% across the Kittitas Valley. High temperatures on Monday will start of 10 to 15 degrees below normal and will mainly range from the 50s in central Oregon to the 60s across the Columbia Basin. By Wednesday, high temperatures will begin to rise and by Thursday, highs will be close to normal in most areas and above normal in the Basin. The ECMWF EFI shows this trend as well for high temperatures. On Monday, there is a large area of -0.7 to -0.8 across most of Oregon, and -0.6 to -0.7 across much of southeastern Washington. On Tuesday, the area moves a bit eastward. There is a large area of - 0.7 to -0.8 across much of the region and even an area of -0.8 to - 0.9 over the Oregon Blue Mountains. By Wednesday, most of the anomalous temperatures are gone in the EFI. .PRELIMINARY POINT TEMPS/POPS... PDT 70 50 67 41 / 0 20 50 100 ALW 73 54 71 44 / 0 10 40 100 PSC 73 56 72 45 / 0 10 40 90 YKM 69 49 65 42 / 0 30 80 70 HRI 75 54 70 43 / 0 20 50 90 ELN 67 44 61 42 / 0 30 80 70 RDM 65 41 50 32 / 10 70 90 70 LGD 65 46 63 39 / 0 10 50 100 GCD 64 45 61 35 / 0 10 90 100 DLS 72 49 57 46 / 10 60 90 90 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory from 5 AM Saturday to 11 AM PDT Sunday for ORZ509. WA...None. && $$ UPDATE...75 SHORT TERM...91 LONG TERM....77 AVIATION...97 ####018007805#### FXUS65 KRIW 031739 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1139 AM MDT Fri May 3 2024 .KEY MESSAGES... - Snow and rain showers today, ending from West to East. - Saturday looks dry and mild. Snow returns to the west Sunday, with windy and warm conditions East of the Divide. - Cool, blustery and unsettled much of next week. The heaviest precipitation is expected in northern Wyoming. Details past Monday remain uncertain. && .DISCUSSION... Issued at 334 AM MDT Fri May 3 2024 The forecast today will have two prominent words beginning with W. The first is the state we are in Wyoming. The second is the season that seems to last longer than any other here, winter. Winter is reminding us that it is not done yet. Snow is currently ongoing across much of the west, courtesy of a trough and cold front moving into western Wyoming, with a circulation noted over eastern Idaho. As I write this around 2:30 am, areas East of the Divide are mainly dry. There is rather dry air at the surface, this evening's sounding showed it and the tell tale donut hole in the imagery over the radar site is showing the snow is having trouble reaching the ground. Dew point depressions are still rather large, but it should be snowing by the time most people wake up. If you don't like snow, this will be good since the longer it takes to start, the less that can accumulate before the sun comes up. After around 8 or 9 am, the strong May sun should keep roads mainly wet and limit accumulation. Even now, only some of the passes are slick. Reasoning on the timing of the precipitation remains the same, with the steadiest in the morning, then gradually tapering off in the afternoon as the system moves to the east. All showers should end by around 9 pm tonight. Many locations will see some accumulation of the grass, but this will be elevation dependent. For a rough guide, the 1 in 2 chance of an inch or more of snow lies mainly above or below 6000 feet in areas of central Wyoming.Far northern areas will see the least chance of snow. With the clouds and precipitation, temperatures will average below normal. Much of the weekend looks dry and warm, especially East of the Divide. Saturday looks to be the nicest day with high pressure over the area, bringing sunshine, near to somewhat above normal temperatures and mainly light wind. As for Sunday, the approaching, more potent Pacific system appears a bit slower, so POPs and QPF were reduced across the west during Saturday night and Saturday morning. We did maintain a small chance of convection East of the divide late, but this is looking less likely with less than a 1 in 5 chance in any location. Most locations East of the Divide should be dry through sunset with downsloping, southwest flow continuing. This will bring in additional concerns though. One, the potential for strong to potentially high wind. I would put the chance at 1 out of 3 at this point. This will especially be case in areas prone in southwest flow, like Casper, the Green and Rattlesnake Range and possibly Lander. The strongest winds may end up being across southern Wyoming, closer to the jet energy, courtesy of the right front quadrant of an 100 knot jet streak. Another clue is 700 millibar winds, with some 50 to even 60 knot barbs showing up in southern Wyoming. There could also be elevated fire weather, although increasing dew points may mitigate this. Temperatures will peak Sunday East of the Divide, with mainly locations rising into the 70s. Heavier precipitation will move into the west in the afternoon and especially in the evening as the low moves toward and area and the best lift from the left front quadrant of the aforementioned jet streak approaches the area. Snow levels look to remain above 7000 feet through the day as 700 millibar temperatures hold at minus 3 or warmer. Colder air will move in at night though and drop snow levels to the floor across the west. Favorable, moist westerly flow will keep snow going in the mountains into Monday as well. There is greater than a 3 in 4 chance of over a foot of snow across the Tetons and over 6 inches across the remainder of the western mountains. Some highlights will likely be needed over this period. Meanwhile, in areas East of the Divide, rain and snow will overspread the area. With the expected track of the low to be across central Wyoming, the main impacts would be in northern Wyoming. This would especially be the case in Johnson County and the Bighorns, where upslope will be favorable and wrap around precipitation may continue as the low moves slowly to the east. There is more uncertainty for amounts here with more model differences. It also looks warmer here, with 700 millibar temperatures falling to around minus 5 or so. This would keep snow levels around 6000 feet or higher, keeping the populated areas mainly rain. Several inches of snow will be possible in the Bighorns though, with a greater than 1 in 2 chance of advisory level amounts. Reasoning remains the same through much of the week, as a blocking ridge sets up across the Great Lakes and the upper level low can only move slowly away and long wave troughing hangs over the Rockies. No major storms are expected. The main concern will be wrap around precipitation and if it can move into northern Wyoming. Uncertainty is high on details here through. A tight pressure gradient will also stay across the area, keeping gusty to strong wind going across many areas possibly through Wednesday before finally weakening. So, to sum up the extended, we have high confidence (greater than 4 in 5) of a cool, blustery and damp pattern through much of the next workweek. Confidence on the details past Monday remains very low, however. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1139 AM MDT Fri May 3 2024 West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals. An upper-level low is rotating through southwest Wyoming late Friday morning. Cold core and added lift will generate scattered snow showers and potentially brief MVFR conditions until around 21Z. In general, terminals remain VFR through the period. Gusty west to northwest wind 15-25kts becomes widespread by mid-afternoon on the backside of the upper low. Wind speeds diminish early this evening and lingering mid-cloud decks give way to a clearing sky. Mountain tops frequently obscured above 10K feet MSL until 01Z/Saturday. East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals. Moisture axis streaming across central Wyoming coupled with jet energy will support IFR/MVFR at KCPR until 20Z-21Z Friday. Improvement is already being noted at KRIW and KLND where the snow ends and VFR returns between 18Z-20Z Friday. KCOD sees VFR conditions develop during that same time period. Mid-cloud decks will clear between 23Z-02Z Friday evening. A clearing sky and sufficient boundary layer moisture may allow for fog development at KCPR and KRIW between 10Z-14Z/Saturday. This will need to be monitored for inclusion with the next routine TAF issuance. Mountains frequently obscured until 21Z, with tops obscured until 01Z/Saturday. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 3 PM MDT this afternoon for WYZ015. && $$ DISCUSSION...Hattings AVIATION...CNJ ####018008032#### FXUS63 KMQT 031739 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 139 PM EDT Fri May 3 2024 .KEY MESSAGES... - Active pattern continues through next week as a series of low pressure systems track across the U.S. and affect Upper MI. Above normal precipitation expected, including chance of thunderstorms at times. - Mostly above normal temperatures expected, generally 5 to 10 degrees above normal on the majority of days thru the middle of next week. && .SHORT TERM /THROUGH TONIGHT/... Issued at 139 PM EDT Fri May 3 2024 Calmer weather is being seen this afternoon as the last of the cloud cover has lifted away from the far east. With sunny skies being overhead the rest of this afternoon and with subtle warm air advection continuing, highs today could get into the mid 60s to low 70s before this evening; some spots, including Watson, Marquette, and L'Anse, have gotten to 68F already. Otherwise, gusty WSW'rly winds across the western half continue the rest of this afternoon before dying down this evening as deep mixing takes place across our region. Moving into tonight, cloud cover looks to return to the west half late as another low pressure system from the Central Plains looks to lift towards the U.P.. As it does so, we could see a few sprinkles late tonight from time to time across the west. Therefore, while skies will be mostly clear for tonight, the western half's low temperatures tonight will be a few degrees warmer due to the incoming cloud cover; temperatures are expected to get down to the mid 40s near Lake Superior, the low 40s over the western interior, and upper 30s in the interior east tonight. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 542 AM EDT Fri May 3 2024 Overall, the first half of the extended period (tonight through Monday night) is mostly dry and sunny as high pressure tracks across the area with just a brief chance for rain showers on Saturday. Elevated fire wx conditions may occur each day Sat - Mon, but are more likely on Sunday and Monday when sunny skies help us dry out. On the other hand, we return to a pattern with frequent rain chances for the Tuesday thru Friday time frame as a broad area of low pressure spins across the region. There are early signals for a prolonged stretch of drier weather starting the weekend of May 11/12, but temperatures appear to average near normal at this time. Starting with tonight, weak surface ridging to our east results in light southerly flow with upper level cloudiness spreading across the western UP overnight. Mostly clear skies across the east should allow for good radiational cooling into the upper 30s away from downsloping along the Lake Superior shoreline. The next weather maker approaches Saturday morning and most guidance suggests a weak but deepening surface low. Rain chances spread across the western UP during the morning which keeps high temps cooler (around 60F) compared to the central and especially the east where highs approaching 70F are forecast. Warmer temps/deeper mixing across the east within the dry pre-frontal air mass suggests potential for locally elevated fire wx conditions. It's worth noting that both NAM and GFS soundings show single digit RH values in the mid-level dry layer that we'll be mixing into. Increasing cloud cover should limit mixing potential, but conditions appear to be trending more volatile across the east ahead of Saturday's rain chances. The cool front and associated rain chances spread across the central and eastern UP during the afternoon and evening, respectively. The NAM-3km even delays precip at Newberry until around midnight or 3-5 hours later than the GFS. HREF ensemble mean MUCAPE remains less than 100 J/kg, but HRRR simulated radar indicates an increasingly convective pattern as showers track east across the area. Overall, the forecast may still exaggerate the rain potential with this system since model soundings only show a 3-6 hour window of rain chances at any one location. Limited instability and duration indicate light amounts are most likely. Dry high pressure settles across the area on Sunday allowing sunny skies to spread across the area during the morning hours. In fact, CAMs suggest potential for fog resulting from moisture lingering in a boundary layer inversion beneath clearing mid/upper level clouds. A more straight-forward radiation fog setup could materialize Sunday night under high pressure, clear skies and light winds. Otherwise, fire weather is the primary concern for the Sunday-Tuesday period. Sunday and Monday are both likely to see min RH dipping below 30% across the interior, but light winds temper the fire wx threat. Stronger winds are expected on Tuesday and if the dry air mass lingers a bit longer then Tuesday likely represents a more volatile combination of low RH and winds. However, that possibility depends on rain chances being delayed until late in the day which current model blends do not indicate. Late week rain chances are associated with a deep closed low developing across the Northern Plains late on Monday that slowly spins eastward over the subsequent week. Moderate rainfall and embedded thunderstorms are again possible with the warm front passage Tuesday/Wednesday followed by spottier showers Thursday/Friday. A cold core upper low suggests a large diurnal component to the late week shower activity. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 109 PM EDT Fri May 3 2024 VFR conditions continue through most, if not the rest of the TAF period as weak ridging moves over us the rest of this afternoon. Starting late tonight, another low pressure currently over the Central Plains lifts northeastward towards the Upper Midwest and brings more rainfall to the west as soon as Saturday morning (although some sprinkles could be seen here and there tonight). This incoming rainfall could bring MVFR and possibly lower conditions back across KIWD by the end of the TAF period. Meanwhile, expect the gusty WSW'rly winds to die down later today as the sun sets. While we could see some marginal LLWS over the TAF sites (namely KCMX), the chance is only around 20 to 30%. Therefore, LLWS was not put into the KCMX TAF at this time. && .MARINE... Issued at 542 AM EDT Fri May 3 2024 Light winds, mainly out of the south-southeast are currently being observed across Lake Superior and winds are expected increase while veering southwesterly today. While gusts up to 25kt are expected over western Lake Superior this afternoon, winds diminish to less than 20kt tonight. Expect winds mostly below 20kts across Lake Superior this weekend, but northwesterly winds increase to around 20 knots Saturday night behind a cold front before becoming light again on Sunday. High pressure that arrives over the Upper Great Lakes late this weekend shifts eastward on Mon while a deep low pressure emerges over the western Dakotas. This will result in increasing easterly winds late on Mon into Tue when gusts up to 30kts are expected. Patches of locally dense fog are occuring over western Lake Superior this morning, which is expected to push mainly into Canadian waters as south/southwesterly winds increase today. If fog does not clear off of the lake today then additional rain chances on Saturday may result in increasing fog coverage. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Small Craft Advisory until 5 PM EDT this afternoon for LSZ242>244-247. Lake Michigan... None. && $$ SHORT TERM...TAP LONG TERM...EK AVIATION...TAP MARINE...EK ####018004280#### FXUS63 KARX 031739 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 1239 PM CDT Fri May 3 2024 .KEY MESSAGES... - Areas of fog this morning. This fog may be localized dense. As drier air moves into the region and diurnal mixing occurs, this fog should burn off rapidly between 8 and 10 AM. - Rain and scattered storms are expected late tonight and Saturday. This rain will likely only last up to 6 hours in any location. With better forcing and moisture transport into the region, rainfall amounts were increased. They now look to range from a tenth to a half-inch. Highest rain totals look to be west of the Mississippi River where the forcing and moisture transport is the best. - For early next week (Tuesday and Tuesday night), there appears to be risk of severe weather. While the shear looks good, still some uncertainty of the amount of instability. && .DISCUSSION... Issued at 334 AM CDT Fri May 3 2024 This Morning - Areas of fog - potentially dense The combination of clearing skies, light winds, and recent rainfall will result in the development of fog across much of the area early this morning. There may be even some localized dense fog. As drier air moves into the region and diurnal mixing develops this fog should quickly dissipate between 03.13z and 03.15z. Late Tonight through Saturday - Rain and scattered storms The 05.03z models are in good agreement that a longwave trough will move east through the forecast area from late tonight into Saturday. Ahead of this wave, a 40 to 50-knot 850 mb jet will increase the moisture transport across the area. Precipitable water values will increase into the 1 to 1.4 inch range. The highest values will be south of Interstate 90. This is higher than the past couple of days. Due to this the precipitation totals were increased. They now range from a tenth of an inch to a half-inch. The highest values will be likely west of the Mississippi River where the forcing and moisture transport will be the strongest. The CAMs show that the rain and scattered storms will likely only affect an area up to 6 hours. Used the CONSShort and the CAMs to try and add some timing to this precipitation. Even by doing this, still likely holding onto this precipitation a bit too long. While the 0-6 km shear increases into the 40 to 50 knot range (highest north of Interstate 90), the 0-4 km most-unstable CAPES remains below 100 J/kg, so not anticipating any severe weather from these storms. Monday Night into Tuesday Night - Another round of showers and storms The models continue to show that a closed 500 mb low will lift out of the desert southwest and move into the Northern Plains on Monday. A negatively-tilted shortwave trough will move northeast through the area on Tuesday. This will likely result in a line of showers and storms. Both the deterministic GFS and ECMWF suggest the potential for the 0-6 km shear will be in the excess of 40 knots. The main question continues to be the timing differences with this system which greatly impacts the amount of instability that will be found across the region. Colorado State severe probability still shows a 15 to 30% chance in northeast Iowa and southwest and central Wisconsin. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1239 PM CDT Fri May 3 2024 Light southwesterly winds expected through the evening, then shifting to southeasterly winds for the overnight period. A line of showers will move through Saturday mid-morning and early afternoon across the area. There is around a 30% chance of thunder to occur within this line, so thunderstorms can not be ruled out. Lower flight categories are expected, especially MVFR conditions. IFR conditions will be possible, as there is between a 20 and 40% chance of IFR CIGS to occur during the morning and afternoon. The wind will shift to the northwest across the area during the afternoon. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Boyne AVIATION...Cecava ####018005849#### FXUS63 KGRR 031739 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 139 PM EDT Fri May 3 2024 .KEY MESSAGES... - Showers and thunderstorms taper off today - Next Chance Showers Saturday Night; Dry Sunday into Monday - Continued Mild Next Week with Occasional Showers and Storms && .UPDATE... Issued at 1147 AM EDT Fri May 3 2024 We did lower the temperature a few degrees for today. The clouds and light precipitation were holding back the temperatures. Despite some sun returning this afternoon, it looks like we will fall short of the forecasted values, based off of trends and the latest model guidance. && .DISCUSSION... Issued at 343 AM EDT Fri May 3 2024 - Showers and thunderstorms taper off today Numerous showers and scattered thunderstorms cover the area first thing this morning. These storms have been just some good old fashioned garden variety storms with some isolated small hail and wind gusts of 30 to 40 mph winds. We will see more of the same over the next few hours, with the thunder threat diminishing a bit as the better instability shifts east. The area is under a nice moist axis, out ahead of a front that is over Eastern Wisconsin as of 07z. Instability is weak with only a few hundred J/kg of CAPE and slightly negative LI's. These parameters are just enough to produce some lightning and thunder. It looks like we should see the front gradually start clearing the area from West to East after 13-14z. With the front clearing the area, the showers and storms will be coming to and end also. We should see some sunshine break out this afternoon in the wake of the front, bring a nice half day to the area. The only thing of note tonight is the potential of low stratus advecting over the southern half of the area from the SE overnight. All of the low clouds/moisture getting swept out with the front will make a partial return overnight. The low level flow becomes from the SE, and taps the low level moisture with the front. Tough to say how far it will make it. The far SE portion of the area toward Jackson has the best chance, while the Muskegon area and areas north will see the lowest chance being further removed from the moisture source. Most of the day on Saturday will remain dry and warm. There are a couple of small chances for a little bit of spotty rain. The first is over the SE portion of the area during the afternoon. The lingering low level moisture, combined with a weakening front moving over the area may touch off a few showers/weak storms. The second area that may see a few showers late in the afternoon will be the lakeshore, with northern areas seeing the best chance. The front that meanders over the area on Saturday will be mainly dry. We do see some almost pure convergence develop along/behind the front, and a weakening short wave aloft. These factors will combine to produce a line of showers and isolated storms, possibly as early as late Saturday afternoon at the lakeshore. - Next Chance Showers Saturday Night; Dry Sunday into Monday A weak cold front will cross the state on Saturday night into early Sunday with a few showers and storms along it. High pressure builds in behind the front providing a period of dry weather Sunday into Monday before a warm front returns north on Monday night and Tuesday. - Continued Mild Next Week with Occasional Showers and Storms Guidance pops still 70-80 percent Tuesday/Tuesday evening as Plains trough sends out a shortwave in our direction, although some timing differences on this feature are still present. The middle to late part of next week appears to remain rather active as broad/positively tilted longwave trough edges slowly in our direction. Series of fronts/troughs pivoting around a slowly approaching upper level low along with lingering warmth/instability will maintain a daily convective threat. Temperatures remaining above normal most of next week before cooling off next weekend with the eventual arrival of the upper low/trough. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 136 PM EDT Fri May 3 2024 A cold front is moving slowly across Lower MI this afternoon. A line of showers has developed along it between GRR and LAN. This line should clear LAN/JXN by 21z. Cigs are generally MVFR but a few pockets of IFR exist. Look for improvement by the end of the afternoon when VFR conditions will develop. Models show a fairly strong signal for stratus to develop over Canada tonight and move east in easterly flow. We'll see IFR develop overnight at LAN/JXN and then spread west and lift a bit as it approaches GRR/MKG. && .MARINE... Issued at 343 AM EDT Fri May 3 2024 It appears that we should not need any marine headlines through at least Saturday. We could be looking at a possible Small Craft Advisory event for Saturday night and Sunday. Even with the system overhead this morning, there is not much of a pressure gradient on either side of it, so no big wind events for the time being. We do see a weak front slide over the area on Saturday, and then move out by Sunday. The way the systems come together, there ends up being a decent gradient on the back side of the system that could push winds up above thresholds Saturday night into Sunday. The next potential headline event after Saturday Night/Sunday will be Monday night into Tuesday with the next system. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ UPDATE...MJS DISCUSSION...Meade/NJJ AVIATION...04 MARINE...NJJ