####018003913#### FXUS64 KOUN 132345 AFDOUN Area Forecast Discussion National Weather Service Norman OK 645 PM CDT Mon May 13 2024 ...New AVIATION... .UPDATE... Issued at 336 PM CDT Mon May 13 2024 With winds going light and variable tonight under clearing skies, could see some radiational fog develop across southeast Oklahoma. As a result, added patchy fog into the wx grids during the first half of Tuesday morning across southeast Oklahoma. NAM fairly aggressive with the fog becoming more dense (visibilities reduced below 1/4 mile) so may need to amend if necessary. No other chances were made to the forecast. && .SHORT TERM... (This evening through Tuesday) Issued at 315 PM CDT Mon May 13 2024 A mid/upper-level low in Kansas will continue to slowly move eastward toward the Midwest. Showers and thunderstorms will continue to develop on the trailing wind shift across east central into southeast Oklahoma. A few widely scattered showers and thunderstorms will also occur across across north central into central Oklahoma in association with the upper-level low itself. The convection should exit by early evening. For Tuesday, mid-level heights will rise as the mid/upper-level low moves toward the Midwest. Dry and warmer conditions are expected with abundant sunshine. Mahale && .LONG TERM... (Tuesday night through next Sunday) Issued at 315 PM CDT Mon May 13 2024 By Wednesday, a quasi-stationary boundary is forecast to be located somewhere across northern Oklahoma as a shortwave trough lifts into the Plains. The location of this boundary may depend on earlier convection in Kansas (i.e., reinforced by outflow). Low- level moisture pooling and low-level coverage along this boundary appears sufficient for convective initiation for showers and thunderstorms. Strong to severe thunderstorms will be possible. On Thursday, a more substantial shortwave through will approach the Southern Plains. If there is sufficient recovery Thursday afternoon from the previous night's convection (and depending on the location of the effective cold front), strong to severe thunderstorms will be possible again on Thursday. In addition to severe weather, heavy rainfall that may lead to flooding will be another potential hazard (especially if heavy rainfall occurs on Wednesday). The trough will be slow to exit with at least a low chance of rain continuing into Friday. By the weekend, a ~595 dam mid-level ridge is progged to develop across Mexico with the Southern Plains on the northern periphery of the ridge. Temperatures should gradually rise with mid 80s to mid 90s deg F likely as the low-level thermal ridge expands to the north and east. There will also be a continued low chance of showers and thunderstorms with the area near the periphery of the stronger mid-level flow. Mahale && .AVIATION... (00Z TAFS) Issued at 645 PM CDT Mon May 13 2024 There are a few scattered showers that will persist over the next hour or two, mainly in the KDUA and KPNC areas. But these should dissipate early this evening with decreasing clouds. Winds will be light and somewhat variable although primarily from the northwest overnight. The western sites will shift to southerly early Tuesday afternoon. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 56 80 59 87 / 10 0 0 20 Hobart OK 53 84 60 89 / 0 0 10 30 Wichita Falls TX 56 84 61 90 / 0 0 0 10 Gage OK 49 84 57 88 / 0 0 10 30 Ponca City OK 54 79 56 84 / 20 0 10 30 Durant OK 59 82 59 88 / 20 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ SHORT TERM...68 LONG TERM....10 AVIATION...26 ####018003935#### FXUS65 KRIW 132345 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 545 PM MDT Mon May 13 2024 .KEY MESSAGES... - Series of weak shortwaves through Thursday brings sporadic rain showers/thunderstorms and near average temperatures. - Warming trend by week's end into the weekend with any shower activity isolated to the higher terrain west of the Divide. && .DISCUSSION... Issued at 1238 PM MDT Mon May 13 2024 IR shows a pretty meridional pattern with weak ridging to the east and a weak shortwave to the west. Sporadic rain showers and a couple isolated thunderstorms can be had this Monday afternoon for much of the northern half of the CWA east of the Divide. Nothing severe nor significant but a couple lightning strikes expected. As the main trough pushes through supporting a weak cold front for Tuesday, expect more widespread rain showers and thunderstorms much of the day. Cooler temperatures behind the aforementioned front back to near average for this time of year. There is not really much of an impact with this system being very progressive and not much instability nor PVA to work with. Divergence aloft is weak as well being a more flattened meridional pattern. Becoming less active Wednesday as the trough pushes east with ridging building in from the southwest by week's end. Warming trend and mainly dry conditions expected for Friday and over the weekend into the long term. Temperatures back to above average for this time of year with below average precipitation. Any activity will be limited to higher terrain west of the Divide with a more zonal westerly upper level flow. There could be some ripples over time through the pattern but overall, it looks to be quite stagnant through the rest of the month. CPC outlooks concur as well. Fire weather could come to the forefront as fuels dry out with the warming trend this weekend as winds increase to some weaker gusts but enough to warrant to be watched going forward with nothing else really to be of significance at this point in time. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 541 PM MDT Mon May 13 2024 West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals A couple of shortwaves will slide through the region over the next 24 hours. These shortwaves will bring scattered rain showers and isolated thunderstorms to northern/central portions of the area through this evening. The chance remains too low (30%) for prevailing -SHRA, so have VCSH for KBPI/KPNA/KRKS terminals. Sustained wind around 15 knots, with gusts to 25 knots will occur at KRKS/KPNA/KBPI terminals through the afternoon hours today. Gusty erratic wind likely (80%) with any showers/storms. Similar conditions expected on Tuesday, but thunderstorms will be more scattered than isolated Tuesday afternoon. East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals A couple of shortwaves will slide through the region over the next 24 hours. These shortwaves will bring scattered rain showers and isolated thunderstorms to northern/central portions of the area through this evening. The best chance of isolated thunderstorms will be at KCOD/KWRL, so went with VCTS from 21Z-02Z this afternoon for these terminals. An area of -SHRA to SHRA is possible (50%) at KWRL early Tuesday morning. Wind will be 10-15 knots this afternoon. Gusty erratic wind likely (80%) with any showers/storms. Similar conditions expected on Tuesday, but thunderstorms will be more scattered than isolated Tuesday afternoon. 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... None. && $$ DISCUSSION...Lowe AVIATION...Rowe/Myers ####018005956#### FXUS61 KBUF 132345 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 745 PM EDT Mon May 13 2024 .SYNOPSIS... Showers associated with a passing warm front will move across the north country through this evening with some thunderstorm also possible. This front will usher in a period warm and unsettled weather which will last through the middle of the week. After this, a weak high pressure ridge will provide warm and mainly rain-free weather outside of a few afternoon showers. && .NEAR TERM /THROUGH TUESDAY NIGHT/... Showers are found mainly across the eastern Lake Ontario area currently, as a warm front pushes northeast across the region. Showers will push north to the St. Lawrence Valley through the evening. Current temperatures across the area are in the upper 60s to low/mid 70s for most areas. The warmest temperatures are behind the passing warm front, generally across WNY. Some cooler temperatures down to the low 60s can be found in areas where showers are in place. The warm front will stall from the north shores of Lake Ontario to the Saint Lawrence Valley tonight. Chances of showers will linger near the boundary, while the bulk of Western NY will be rain free. Temperatures will fall to the 50s tonight. The frontal boundary to the north will slowly sag southward during the day Tuesday. Limited diurnal instability will develop across Western NY, with showers and a few thunderstorms developing Tuesday afternoon. The greatest coverage will be south and east of Lake Ontario with slightly lower chances on and along its immediate shorelines. Precipitable water values nearing 1.25" not too far above climatological normals, but weak flow aloft will result in slow storm motion. The potential exists for repeated rainfall which could be heavy at times with any convective activity. Modest PWAT values lower the risk for flash flooding, but the risk is non-zero. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... A 500 hPa trough will pass across the Ohio Valley and the mid- Appalachians Wednesday and Wednesday night. While most of the showers associated with this feature will be to our south, there will be a easterly flow of Atlantic moisture into our region that will bring scattered showers through the day Wednesday. Highest chances for showers will be to our east, closer to the deeper Atlantic moisture, but also along a convergent boundary. This boundary, southeast flow around the trough aloft, and northeast flow from a incoming area of high pressure, will serve as a boundary for likely PoPs through the afternoon, and into the evening hours. The light flow could lead to some patches of fog Wednesday night in areas where daytime rain occurred. Highs Wednesday will reach towards 70 near the Lakes, while inland and under deeper moisture and rain showers...mid 60s. Temperatures at night will dip down into the mid 50s. && .LONG TERM /THURSDAY THROUGH MONDAY/... A progressive flow aloft with impulses and shortwaves rippling through will maintain chances for showers and thunderstorms this period, with the best chances for showers and even a rumble of thunder Friday night and Saturday with a trough passage. To start this period, Thursday will be mostly dry, with low PWATS and a narrow ridge of high pressure nearby...this between an east coast low, and trough across the Plains. However there is a possibility that a few showers from the east coast low sneak far enough westward into our eastern CWA. This western trough, and its additional lift, will push eastward, likely in the Friday night to Saturday timeframe. Will place likely PoPs with the trough passage, along with a slight chance for thunder with MUCAPE values around 500 J/KG ahead of the trough. Behind the trough lowering chances for precipitation, through a secondary trough dropping out of Canada may bring chances for showers Sunday. Temperatures Thursday through Saturday will average just above normal, and then the final two days of this period, Sunday and Monday will be even warmer with a milder airmass pushing northward. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... Showers with the potential for a few embedded thunderstorms this evening are found mainly east of Lake Ontario along a warm front that will track north and east of the region this evening. Overall widespread VFR flight conditions, except localized MVFR possible in vsby restrictions in any showers or thunderstorms. Dry weather for most locations tonight as the frontal boundary lifts northward. Some showers may linger near KART which will be closest to the boundary. Mainly VFR flight conditions for tonight through Tuesday morning. Chances for showers and a few thunderstorms increase with instability Tuesday afternoon. Mainly VFR with localized IFR in heavier showers and thunderstorms. Outlook... Tuesday night...MVFR/IFR in showers, stratus, and fog. Wednesday...MVFR/IFR with a chance of showers, along with lingering stratus. Improving later Wednesday and Wednesday night. Thursday...VFR. Friday...VFR. A chance of showers late. Saturday...VFR/MVFR. A chance of showers. && .MARINE... Moderate southwesterly flow today, but winds will be strongest on the land due to lake breeze enhancement. Winds on the waters expected to remain below Small Craft criteria. After this, there will be a relatively weak flow, with winds expected to remain below 15 knots through Friday. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ SYNOPSIS...Apffel/SW NEAR TERM...Apffel/SW SHORT TERM...Thomas LONG TERM...Thomas AVIATION...Apffel/SW MARINE...Apffel ####018004274#### FXUS65 KPSR 132345 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 445 PM MST Mon May 13 2024 .UPDATE...Updated 00z Aviation Discussion. && .SYNOPSIS... Temperatures will remain above normal the rest of this week and into the weekend with the lower deserts close to or just above 100 degrees most days. Dry conditions will persist with the usual late afternoon breeziness. An exception will be the higher elevations of northern and eastern Arizona which will see a few late day showers each day. These showers could be supportive of some erratic, gusty winds descending into the lower deserts each evening. && .DISCUSSION... Overall tranquil weather will persist across the area the rest of this week into the weekend. Mainly just some elevated fire weather concerns with hot temperatures, low humidities and late day breezy conditions through the forecast period. Ensembles in overall agreement with weak ridging over the area today giving way to lowered heights again for Tuesday into Thursday as another upper low off the SW CA coast moves across the SW US. Not much weather with this system outside of maintaining low shower chances across the high country to the north. With steering flow from the north, some late day outflows could see there way south into portions of the Phoenix valley with some erratic winds. This system will keep temperatures in check, but still hot and into the upper 90s/near 100. For the weekend, heights again build across the area ahead of troughiness developing along the west coast into early next week. Ridge stays fairly flat, so nothing extreme and resulting in temperatures coming up just a few degrees for the weekend. Temperatures could be some of the warmest temperatures so far this season by Saturday. With that said, still mostly minor HeatRisk expected. As the west coast trough pushes inland into the northern Rockies early next week, we will have to watch the potential for a bit more wind across our area for increased fire weather concerns once we get into Monday of next week. && .AVIATION...Updated at 2345Z. South-Central Arizona including KPHX, KIWA, KSDL, and KDVT: No aviation weather concerns are anticipated through the TAF period under widely scattered daytime cu aoa 12 kft over the high terrain and FEW-SCT passing high clouds overnight. Wind directions will favor their typical diurnal patterns. A predominant westerly component has been observed through much of the afternoon, which is expected to persist through the evening with occasional gusts of up to 15-20 kt. Confidence is high that the typical SE switch will take hold by 07-09Z at KPHX, KIWA, and KDVT, with lighter wind speeds overnight (aob 8 kt). Southeast California/Southwest Arizona including KIPL and KBLH: No major aviation weather concerns are expected through the next 24 hours. Winds at KIPL will favor a westerly component through the period, with gusts up to 20 kt this evening, except for a period of light and variable winds tomorrow afternoon. Winds will generally prefer S to SW through the period at KBLH, albeit with an extended period of very light speeds and variability early tomorrow morning. Otherwise, mostly clear skies are favored for much of the TAF period outside of passing SCT high clouds this evening. && .FIRE WEATHER... There will be local elevated fire danger this week and into the weekend as a result of some periodic gusty winds (mainly in the afternoon and early evening hours), dry fine fuels, and low humidity levels. MinRH levels will be around 10% across the lower deserts and in the teens for the higher terrain areas. Overnight recoveries will poor to fair and in the 20-50% range. Afternoon and early evening wind gusts will be in the 20-25 mph range, with some periodic higher gusts possible in the higher terrain in the eastern districts due to some high based showers over the mountains. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ DISCUSSION...Frieders AVIATION...Whittock FIRE WEATHER...Frieders ####018005849#### FXUS64 KCRP 132346 AFDCRP Area Forecast Discussion National Weather Service Corpus Christi TX 646 PM CDT Mon May 13 2024 ...New AVIATION... .SHORT TERM... (Tonight through Tuesday night) Issued at 241 PM CDT Mon May 13 2024 Key Messages: ▶ Slight to Enhanced Risk of Severe Thunderstorms through this early evening. A line of showers and thunderstorms is currently tracking across portions of the Victoria Crossroads into the northern Coastal Bend. A few of these storms have become strong to severe with damaging winds and large hail reported. Conditions are conducive for further severe weather development through the afternoon with dewpoints in the 70s, steep lapse rates, MUCAPE values at or around 4000-5000 J/kg and a weakening cap. The Severe Weather Watch has been extended to now include the northern coastal counties and adjacent bays/nearshore waters through 00Z. This activity is forecast to continue on a southeastward progression through the reminder of the afternoon with the highest convective chances transitioning into the waters by early evening. A few discrete cells have redeveloped out west near the Rio Grande Plains along the location of a frontal boundary. Additional severe weather concerns reside with these western storms as they enter a more unstable environment. Very large hail is possible. Conditions are forecast to improve tonight with drier air filtering in behind the boundary. PWATs are progged to drop below an inch by Tuesday while the shortwave trough exists the region and surface high pressure briefly settles. Winds will shift to the north and northeast tonight, and out of the east on Tuesday as the high drifts eastward. Moisture will begin to increase again Tuesday night with the low-level flow becoming more southeasterly. && .LONG TERM... (Wednesday through next Sunday) Issued at 241 PM CDT Mon May 13 2024 Key Messages: ▶ Low to medium chance of showers and thunderstorms Thursday ▶ Heat stress conditions possible Thursday, Sunday, and Monday in the Southern Coastal Plains and Brush Country A shortwave will move across the Southwestern US Wednesday night into Thursday. This will combine with well above normal PWAT values (2.00-2.50 inches), which is flirting with the climatological max for this time of year. The caveat for storm development will be the uncertainty with the CIN values. Models are depicting moderate to strong instability (2500-3500 J/kg), but aren't in agreement with how much of a cap will be over the area. Given the immense amount of instability, it's not out of the question to see some strong to severe storms develop. SPC came to a similar conclusion on the uncertainty with the CIN values which prevented them from issuing an outlook. Models depict a surface trough developing during the day Thursday in West/Central Texas. A chance for showers and thunderstorms does exist nonetheless due to the presence of these factors. This will likely need to be monitored as the situation evolves. Thursday, depending on the uncertainties with convection, could see heat stress conditions across the Southern Coastal Plains and Brush Country. With the abundance of moisture in the area it will be pretty humid allowing for heat indices to increase to around 110. A similar story will follow for Sunday and Monday. The need for a Heat Advisory may come into play during these days and will also be closely monitored as we transition through the week. && .AVIATION... (00Z TAFS) Issued at 635 PM CDT Mon May 13 2024 Complicated situation to start with convection still ongoing, however, it looks like LRD, COT and VCT should be done with the convection for the night. ALI and CRP still have some over the next couple of hours. Otherwise, skies in the west should clear out, and are clearing out with so that VFR conditions are expected for LRD and COT. The moisture from the convection will probably (40-50% chance) produce fog at VCT, ALI, and CRP. However, low confidence in the VSBYs expected. Based on trends would expect MVFR VSBYs, however, some models are showing borderline IFR VSBYs. However, after 12z/Tue, will expect that everything trends back to VFR. && .MARINE... Issued at 241 PM CDT Mon May 13 2024 Showers and thunderstorms will impact the coastal waters this evening in response to a passing disturbance. A few storms could become strong to severe at times, with large hail and damaging winds being the primary hazards. An associated weak frontal boundary will move offshore this evening, shifting the winds out of the northeast through Tuesday morning. A weak to moderate east- southeasterly flow resumes Tuesday afternoon into the overnight period. Drier conditions are in store on Tuesday. Isolated to scattered showers and thunderstorms will be possible early Thursday morning through Thursday evening. Weak to moderate onshore flow is expected to continue through much of the week and the remainder of the period. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 70 91 72 90 / 30 0 0 0 Victoria 65 91 67 91 / 30 0 0 0 Laredo 70 100 73 98 / 10 0 0 10 Alice 68 95 70 93 / 20 0 0 0 Rockport 73 87 75 87 / 40 0 0 0 Cotulla 67 97 70 98 / 10 0 0 0 Kingsville 70 94 71 91 / 30 0 0 0 Navy Corpus 75 88 77 87 / 40 0 0 0 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ SHORT TERM...ANM LONG TERM....NP AVIATION...JSL/86 ####018006295#### FXUS63 KIND 132347 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 747 PM EDT Mon May 13 2024 .KEY MESSAGES... - Showers and a few thunderstorms expected through Tuesday - Up to around one inch of rain expected but locally higher amounts possible - Rain chances return Thursday into Friday, again early next week. && .SHORT TERM (This evening through Tuesday)... Issued at 258 PM EDT Mon May 13 2024 Rest of This Afternoon... Some weak lift ahead of an approaching upper system will work with some limited instability to produce scattered showers and some thunderstorms, primarily across the far western portions of central Indiana. Will go with primarily chance PoPs west. Satellite shows some holes developing in the clouds, so temperatures still look to remain around 80 at most locations. Tonight... Some upper energy rotating around the approaching upper system will bring scattered to numerous showers to the area this evening, then some better forcing will arrive late tonight. Moisture will be plentiful. Will go mainly chance or low likely category PoPs this evening, then increase to likely or higher PoPs overnight as the better energy moves in and interacts with the moisture. With clouds and some rain around, low temperatures will be around 60 degrees. Tuesday... The better forcing that arrives late tonight will continue into Tuesday morning. Will continue with higher PoPs then. There may be a relative lull early in the afternoon, then as heating occurs, additional showers and some thunderstorms will develop with the heart of the upper system arriving. Will continue with higher PoPs. At the moment, instability and shear look low enough to keep severe storms at bay. However, locally heavy rain remains a threat with the plentiful moisture. HREF local probability matched means show some potential for localized amounts over 2 inches. Clouds and rain will keep temperatures lower, with highs in the lower 70s expected most areas. && .LONG TERM (Tuesday night through Monday)... Issued at 258 PM EDT Mon May 13 2024 Active weather looks to continue through the long range with multiple storms systems possible. As of right now, no organized severe weather appears likely. SYNOPTIC OVERVIEW Aloft, the polar jet stream looks to remain at least moderately amplified to at times quasi-zonal. The subtropical jet is likely to remain separate across the southern states. This disconnection should preclude significant moisture transport northward. Nevertheless, waves embedded within the broader flow should pass through the Midwest with some regularity. These waves are modeled to take on a generally west to east path, which makes sense given the lack of phasing and quasi-zonal nature of the jet stream. Like today's system, enough moisture should be present for scattered showers and thunderstorms. The next wave in the series (after today's) arrives late this week around Thursday or Friday. Flow aloft looks rather weak and model soundings are nearly moist adiabatic. Showers and storms are still possible, given synoptic scale forcing...but the weak lapse rates and lack of wind shear will limit severe potential. The third system in the series arrives early next week, Monday or Tuesday. Model consensus diverges quite a bit by this point, however, so besides rain chances not much can be said about how this system will play out. Beyond that, ensemble guidance hints at broad troughing over the western states and into the Plains as we close out the month. That could allow the active pattern to persist for another week or two. The overall signal is not terribly strong, however. FORECAST CONFIDENCE Confidence through the period is average. Model guidance tends to be in agreement through the remainder of this week but diverges over the weekend. By next week, only a loose signal remains and it's hard to draw any conclusions when guidance shows such a variety of outcomes. Still, the overall picture looks a bit more active than normal (CPC 8-14 day outlook showing wetter than normal conditions). Lack of significant ridging should keep temps near normal for the most part. && .AVIATION (00Z TAF Issuance)... Issued at 747 PM EDT Mon May 13 2024 Impacts: - Arrival of showers and thunderstorms pushed back until after 09z - MVFR to IFR conditions developing Tuesday morning with more widespread convection Discussion: Latest satellite imagery and observations show an area of low pressure near Kansas City slowly pushing eastward. Showers and thunderstorms have developed out ahead of it this evening; however due to very dry conditions across Central Indiana, convection has remained just west of the IL/IN state line. Guidance has not been handling the dry air over the region well, bringing in the chance for rain and storms way too early. Based on latest observations and radar trends, have pushed back the arrival of convection until after around 09z tonight. Potential is there for a few showers before 09z near BMG and HUF, however confidence is low in lightning potential and impacts as dry air will likely cause anything to weaken as it pushes near. Confidence still remains high that widespread showers and thunderstorms will spread eastward into Indiana Tuesday morning and persist through much of the day. MFVR to IFR conditions still likely tomorrow, with chances for lightning and heavy rain under the strongest convection. Southerly winds gusting to 20kts will diminish after sunset then weaken overnight to around and under 10 kts. As the low pressure system approaches, expect winds to become more easterly through the night and into tomorrow, remaining under 10 kts. Potential is there for erratic wind directions and speeds under convection. Currently severe weather is not expected. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...50 LONG TERM...Eckhoff AVIATION...CM ####018006140#### FXUS66 KPDT 132348 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 448 PM PDT Mon May 13 2024 Updated Aviation Discussion .SHORT TERM...Today through Wednesday Night... Key Messages: 1. Windy conditions across the Kittitas Valley through Tonight. 2. Elevated river levels on the Naches River. An upper level shortwave will continue to pass through the area this evening, which will allow a slight increase in cloud cover and a pressure gradient to develop along the Cascades to promote elevated winds over the Kittitas Valley, Simcoe Highlands, Eastern Gorge, and the northern Blue Mountain foothills. Maximum wind gusts of 44 mph have already been observed at the Ellensburg Airport, with the pressure gradient and winds expected to peak between 5 PM and 11 PM this evening. This has warranted the issuance of a Wind Advisory for the Kittitas Valley through 11 PM as gusts of up to 50 mph will be possible. The 44 mph gusts occurred during an observed pressure gradient of 8.7 mb between Portland and Spokane, and the pressure gradient is expected to top out just shy of 11 mb via GFS guidance. Confidence in wind gusts reaching 50 mph is moderate to high (70-80%), as the NBM suggests a 75% chance at Ellensburg, increasing to an 86% chance of gusts reaching 47 mph or greater. The consistent above normal temperatures coupled with the mountain snow event preceding the warm temperatures last weekend have allowed for some elevated river levels - primarily for the Naches River. The currently level of the Naches River at Cliffdell is 28.86 feet, as action stage is forecast to be reached Tuesday evening and peak Friday morning at 29.76 feet. Confidence is high (>95%) in this reach breaking into action stage, but low (<5%) in reaching minor flood stage (31 feet). The Naches River at Naches is currently at 15.38 feet, and is also expected to reach action stage (16 feet) Thursday morning. This reach is forecast to peak Friday morning at a level of 16.3 feet before dropping below action stage Saturday morning. Confidence in reaching action stage is moderate (62%), as reaching minor flood stage is low (<5%). All other area rivers are currently forecast to stay well below action stage. An upper level ridge will build offshore as high pressure infiltrates into the region from the west. This will keep skies mostly sunny and conditions dry. Northwest flow aloft will set up in the wake of the passing shortwave tonight into Tuesday, dropping high temperatures slightly by 1-3 degrees from today. Flow will incur more of a westerly component to keep temperatures above normal and increasing high temperatures 5 to 9 degrees Tuesday to Wednesday. Afternoon humidities will be on the decline, dropping about 5% Monday to Tuesday and another 3% to 6% on Wednesday. 75 .LONG TERM...Thursday through Monday...Dry, northwesterly flow continues through Thursday afternoon as high pressure remains anchored off the Pacific Coast. A shortwave will begin to move through the northern reaches of the forecast area Thursday night, producing a slight chance (10-20%) for showers over the Washington Cascades. The shortwave will dig further south through Friday, bringing cooler air with it, though leaving showers generally confined to the Washington Cascades. Temperatures across the area will cool 10 to 15 degrees under the influence of this shortwave, though values still generally remain 5 degrees above seasonal averages. The other impact related to this system will be an increase of gusty to breezy wind both late Thursday and again Friday afternoon. The strongest winds are expected across the Columbia Basin and into the Yakima and Kittitas Valleys where wind gusts of around 35 kts are highly favored (75- 95%). Beyond Friday, model disagreements become more apparent, with the clusters showing variations in both placement of the next area of low pressure, as well as the intensity of it. Current forecast indicates a slightly stronger lean towards a solution with moisture across the Pacific Northwest, though mostly west of the Cascades. The Oregon and Washington Cascades present in this forecast area will see a slight chance (15-30%) for mountain showers into early next week. A slightly better agreement is demonstrated for Monday as low pressure is favored to impact the Pacific Northwest. Cooler temperatures will return, along with a larger coverage area for shower activity. In addition to the Oregon and Washington Cascades, guidance demonstrates the potential (10-20%) for showers to develop across the Blue Mountains on Monday. This system will again create increased winds across the region, with a 50-70% chance for gusts of 30 to 35 kts. Branham/76 .AVIATION...00Z TAFs...VFR conditions to prevail through the period. Sct-bkn CIGS AOA 10kft-20kft AGL will impact sites through this evening, becoming mostly few tomorrow. Winds of 12-17kts with gusts up to 25kts will continue at sites PDT/RDM/BDN/YKM/ALW/PSC through 4Z-6Z tonight, then becoming less than 12kts through the remainder of the period. Site DLS will see winds 17-22kts with gusts to around 30kts through 4Z, then decreasing to 12-15kts with gusts up to 25kts with winds becoming less than 12kts after 10Z. Lawhorn/82 && .PRELIMINARY POINT TEMPS/POPS... PDT 46 74 47 80 / 0 0 0 0 ALW 50 76 52 82 / 0 0 0 0 PSC 53 81 54 87 / 10 0 0 0 YKM 46 81 49 87 / 0 0 0 0 HRI 50 80 50 86 / 0 0 0 0 ELN 46 75 49 82 / 0 0 0 0 RDM 41 73 43 80 / 0 0 0 0 LGD 44 72 44 77 / 0 0 0 0 GCD 42 73 44 79 / 0 0 0 0 DLS 50 80 53 85 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...Wind Advisory until 11 PM PDT this evening for WAZ026. && $$ SHORT TERM...75 LONG TERM....76 AVIATION...82 ####018006439#### FXUS63 KMQT 132348 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 748 PM EDT Mon May 13 2024 .KEY MESSAGES... - Dry weather continues through Wednesday, then periods of showers expected with a few embedded t-storms possible Thursday through the weekend. && .SHORT TERM /THROUGH TODAY/... Issued at 120 PM EDT Mon May 13 2024 Ridging has filtered into the region today as high pressure emanating out of northwestern Ontario inched closer. The result has been clear and hazy skies with northerly to northwesterly flow across the area. The haze has improved through the day per webcams and GOES 16 imagery, but there's still some lingering and some minor visibility restrictions being observed in some places, namely close to or on the other side of the WI/MI stateline. Daytime highs have climbed into the 50s and 60s, save for mid-upper 40s by Lake Superior. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Issued at 443 PM EDT Mon May 13 2024 Mid-level ridging in central Canada will support sfc high pres over Hudson Bay for the next few days. This high extends ridging s across the Northern Plains and Upper Mississippi Valley through Wednesday. Northerly flow off the Lake on Tuesday results in a north-south temp gradient with temps around 50F near Lake Superior to mid 60s farthest from the lake. Lighter easterly flow on Wednesday allows for deeper mixing and warmer temps approaching 60F near Lake Superior and 70F across the interior. Models have broad agreement on troffing progressing into the central U.S. bringing the next rain chances, mainly on and after Thu. Thereafter, model spread rapidly increases into and thru the weekend due to major differences in timing/amplitude of waves rounding a ridge just off of the W Coast. These differences translate to a very uncertain progression and amplitude of waves downstream to the Great Lakes region. At this time, a return to a pattern characterized by frequent rain chances is favored. Ensemble guidance also indicates a chance for a system to bring a period of widespread steady rain early next week. Temps during the last half of the week should tilt toward above normal, but that will depend on the amount of cloudiness and precipitation. Next week, ensembles suggest temps will generally be on the cool side of normal under fairly widespread negative height anomalies across a good portion of the northern half of the Lwr 48. Beginning tonight thru Tue night, aforementioned sfc high pres extends south across the Upper Great Lakes region. Fcst soundings suggest mainly clear nights tonight and Tue night and a mainly sunny day on Tue. With sfc high pres ridge more firmly over the area Tue night, Tue night will likely be the cooler night though there may be some high clouds to contend with. Precipitable water is not especially low to really enhance the cooling potential. Still, with precipitable water running 55-70pct of normal, will favor the lower side of available guidance, especially Tue night. Expect min temps ranging thru the 30s F tonight, coolest interior w half. Tue night should be a little cooler with mins at traditional interior cold spots having a better shot at slipping just blo 30F. A gradient onshore wind enhanced by the lake breeze component on Tue will lead to cool conditions along Lake Superior. Expect highs in the upper 40s F there. Temps will range up to the mid 60s F well inland interior w half. Drier air aloft mixes down to the surface during the aftn resulting in RH falling to 20-30pct interior w half, but lighter winds not gusting above 15mph will limit fire weather concerns. Sfc high pressure slides east across Ontario resulting in dry easterly flow downsloping off the Canadian Shield. Increasing upper level clouds and Canadian wildfire smoke/haze may limit warming, but lighter winds should allow temps to warm to at least the upper 50s near Lake Superior. Temps are only expected to be a few degrees warmer across the interior where highs approach 70F. A low amplitude mid-level trof tracking across the Northern Plains on Wed approaches the Upper Great Lakes on Thu and shortwaves pivoting around the trough bring periodic rain chances. Shra associated with this feature could spread into western Upper MI late Wed night, then progress eastward on Thu. The forecast package continues to trend toward a later arrival of rain, especially across the east where rain chances don't arrive until Thursday night (e.g. RGEM/NAM). Given the magnitude of antecedent dry air, this trend may continue but the warm/moist air mass eventually moves in bringing rain chances. There is fair agreement that Fri will be a drier day, but not necessarily dry everywhere all day. Almost daily shortwave passages suggest a return to a pattern similar to April 26 - May 4 when 7 of 9 days had measurable rainfall at WFO MQT. Fcst reflects schc/chc of rain showers over the weekend and while widespread or soaking rain is not expected, there will be rain chances in the area. Warmer night time lows and damp conditions suggests bug spray season has arrived. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 748 PM EDT Mon May 13 2024 Despite haze from upstream Canadian wildfires, VFR conditions will prevail for the duration of the TAF period. Some northeast wind gusts up to 21 kts will persist through this evening at SAW. && .MARINE... Issued at 443 PM EDT Mon May 13 2024 Sfc high pressure over Hudson Bay extends ridging south across the Northern Plains and Upper Mississippi Valley today. Ridging drifts east across the Upper Great Lakes thru Wed. As a result, expect winds mostly under 20kt, except for NE winds gusting up to 25kt over far western Lake Superior on Wednesday. Winds will continue to be mostly under 20kt Thu/Fri as a broad trough tracks over the region, bringing warmer temperatures and stable conditions to Lake Superior. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JTP LONG TERM...EK/Rolfson AVIATION...TDUD MARINE...EK/JTP ####018005818#### FXUS62 KCAE 132348 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 748 PM EDT Mon May 13 2024 .SYNOPSIS... Unsettled weather will remain with some rainfall possible through midweek. A bit drier air moves in for Thursday before moisture returns for the weekend. Temperatures near to slightly below average. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... Current satellite and regional radar imagery showing large scale MCS moving along the Gulf Coast this afternoon. This feature will continue to track off to the east this evening, with a trailing convective system them possible late tonight and towards morning. Even that second system appears as if the main track will remain off to the south of the cwa. So, for our area a typical Panhandle Rob Job (PRJ) could be on tap overnight as convection keeps the deeper moisture and rainfall further south of our cwa. This would mean a more stable airmass and lighter rainfall overnight as deeper moisture will be south of the area. Models trending in that direction, and pass the best rainfall south of the CSRA, and only have scattered showers moving through overnight. May actually end up with a period with little to no rain late tonight, but will still keep at least chance pops in late. Temperatures will generally only drop into the low to mid 60s as clouds slow the overnight drop. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... Uncertainty remains in the short term period as to the progression of precipitation through Tuesday. A strong MCS is expected to move to the south of the area which typically limits convective potential for our area but recent runs of the CAMs have trended this slightly faster which may allow for the potential for some destabilization across the area into the afternoon with PWATs expected to be anomalously high. It appears the most likely evolution is a round of rain for the area associated with strong isentropic lift, with a warm front to the south, followed by a bit of a lull in precip chances before a strong shortwave moves through the forecast area. This should generate numerous showers and thunderstorms during the afternoon. The overall severe threat remains low with HREF mean indicating around 1000 J/kg of sbCAPE across the area during the afternoon, although deep layer shear will be sufficient to support organized storms. As a result, we do remain in a day 2 marginal risk from SPC mainly for the potential for isolated damaging wind gusts. Locally heavy rain will likely be observed with any storms but they should be moving fast enough to prevent flooding issues, unless significant training is observed. As the upper forcing associated with the shortwave continues moving to the northeast, precip chances will continue to decrease overnight Tuesday. Models remain consistent in bringing the main upper low through the area Wednesday which even with a slight decrease in moisture, LREF members indicate there remains a high probability (65 to 75 percent) of PWATs remain above an inch and a quarter, especially across the northwestern portion of the forecast area. With pops remaining low in the morning, this should allow moderate destabilization into the afternoon. Deep layer shear expected to be slightly lower than Tuesday but still should be sufficient to support at least multi-cellular convection which with some drier and cooler air aloft, could lead to the potential for hail or some stronger wind gusts. I-95 corridor is in a marginal risk for severe weather for now but would not be surprised if that is expanded to include more of the NE portion of the area. && .LONG TERM /THURSDAY THROUGH MONDAY/... Ensemble means remain consistent in ridging building over the area Thursday which will lead to relatively quiet weather. Quite a bit of uncertainty for the end of the week into the weekend with the overall 500 mb generally supporting southwesterly flow, although ensemble members remain split as to how amplified this pattern will become which is leading to significant differences in timing of the progression of shortwaves through the flow. At the very least, moisture will be anomalously high across the area Friday into early next week which will at least support diurnally driven convection each day through the end of the period. Blended guidance also supports near average temperatures each day, which for reference this time of year, is mid-80s for highs to low 60s for lows. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... Restrictions expected to dominate the TAF period. VFR conditions remain across the terminals however restrictions are just SW of AGS/DNL. By 04z expect restrictions to move into all terminals as the inversion traps moisture near the surface and cigs lower to IFR. With MCS moving south of the area have removed mention of VCSH for a few hours late this evening through the early morning hours. Increasing confidence in showers returning to the area during the early morning hours and becoming widespread around daybreak keeping cigs IFR and vsbys in the MVFR range. Showers will begin diminishing during the afternoon however cigs are expected to remain MVFR through the end of the period. Winds will be southeasterly at 7 knots or less through early afternoon then turn southerly for the remainder of the period. EXTENDED AVIATION OUTLOOK...Showers and thunderstorms and associated restrictions are possible Tuesday night through Wednesday and again Friday and Saturday. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$