Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/13/22

Area Forecast Discussion
National Weather Service La Crosse WI
611 PM CDT Tue Apr 12 2022 .DISCUSSION...(This evening through Tuesday) Issued at 254 PM CDT Tue Apr 12 2022 Key Messages: - Gusty winds/scattered storms late this afternoon with hail potential - Severe weather risk this evening/tonight, highest west of the MS River - Strong, gusty winds likely on Thursday Tonight: Severe Storm Risk The main focus late this afternoon and tonight remains on severe storm potential. Preceding the surface low, gusty S/SE winds have developed in conjunction with strengthening low-level flow. Gusts have locally reached 45 to 50 mph in some areas so did issue a short wind advisory for areas west of the MS River. Additionally, showers and storms will continue to translate northeast with a slug of strong mid-level warm advection on the edge of the elevated instability axis through late afternoon. With the steepening mid- level lapse rates, any storms may produce some hail, with a few storms likely to produce hail to 1"+. Heading into this evening, the filling surface low will lift from eastern NE into southern MN with its associated warm front lifting north into the area. Despite the extensive low clouds north of the boundary, an airmass change will occur as the boundary lifts north with increasing dew points/temps. While a plume of elevated instability will lift north through the afternoon/evening as lapse rates steepen aloft, a pool of MLCAPE will spread north and east more gradually and weaken ahead of the low/cold front this evening/tonight. After the initial warm advection storms, the general expectation is for storms to develop late this afternoon closer to the triple point in western IA/eastern NE/southwest MN spreading east through evening and likely organizing into a linear band of storms by the time they approach. HREF UH paintballs show clustering across western IA/southern MN during the evening, with storms approaching the local area by late evening (10-11 pm), weakening as they track east into WI overnight. Scattered elevated storms also could form by early to mid evening near the warm front in northern IA/southern MN/northern WI as the low-level jet strengthens posing primarily a hail threat given the strong low-level stability/capping in the warm sector. There remains some uncertainty in the evolution/strength of the storms late this evening. RAP soundings show fairly stable/capped low-levels despite the moistening/increasing MLCAPE through the evening. The window for surface-based storms looks quite narrow, focused right ahead of the approaching front. This is when the risk for damaging winds or an isolated tornado would be maximized with any bowing segments/mesovortices, especially across far southwestern counties where HREF/RAP fields show SBCAPE/MLCAPE maximized over 1000 J/kg. Some severe weather risk could persist into western WI, although buoyancy will be on the decline overnight as storms move into this area. Despite the impressive low-level shear, the low-level thermodynamic profiles and late evening/overnight timing decreases confidence in the overall threat, especially with eastward extent, but it will be an evening to keep on eye on trends as storms begin to develop, given the rapid airmass change as warm, moist air advects north. Wednesday/Wednesday Night Upper level closed low over the Northern Plains States lifts slowly northeast into northern Minnesota Wednesday into Thursday. Several pieces of energy rotate around the closed upper level low into the Upper Mississippi River valley. Main surface front passes across the forecast area early Wednesday morning. This will push the deeper moisture transport/east of the forecast area during the day Wednesday. However...with pieces of energy rotating around the upper closed low...showers and potentially a few thunderstorms will linger mainly along and east of the Mississippi River Wednesday afternoon. Cooler temperatures will advect in behind the surface front and allow for temperatures to remain nearly steady or fall into the middle 40s to lower 50s by middle of Wednesday afternoon. Thursday Focus turns to the windy conditions across the forecast area Thursday. Combination of pressure gradient tightening and winds aloft mixing down to the surface will produce windy conditions across the forecast area. Both of the NAM/GFS Bufkit soundings show 45 to 50 knots at the top of the mixed layer. Expect wind gusts to be 40 to 50 miles per hour. Along with the windy conditions...rain/snow showers will develop Thursday afternoon and mainly over the northern half of the forecast area. Friday through Tuesday Main forecast concerns Friday through Tuesday are precipitation chances Sunday into Monday. Upper level closed low/trough slowly pulls east of the Upper Mississippi River valley and another shortwave trough will track into the Northern Plains States this weekend. The 12.12z deterministic GFS/ECMWF show some differences on the strength with the shortwave trough. This will have impacts on timing of precipitation chances. Depending on temperatures Sunday into Monday...light snow will continue to be possible across much of the forecast area. The deterministic models continue to show cooler airmass filtering in with the shortwave trough and into early next week. The 12.12z GFS/ECMWF indicate 925mb temperatures around 0 degrees celsius to minus 4 degrees celsius through the forecast period. Temperatures will remain well below normal...with highs mainly in the 40s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 611 PM CDT Tue Apr 12 2022 The next round of convection is quickly developing over northern Iowa and is expected to expand northeast into the area this evening. Current expectations are that thunderstorms will be possible at both sites from mid-evening through about midnight or so with MVFR/IFR conditions. Behind the storms, lingering showers/rain for awhile overnight with what should be VFR ceilings before the ceilings go back down to MVFR late tonight as the showers/rain come to an end. The winds will be gusty out of the southeast this evening coming around to the south/southwest overnight before going west once the front goes through early Wednesday morning. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ DISCUSSION...DTJ/JM AVIATION...04
Area Forecast Discussion...CORRECTED
National Weather Service Brownsville TX
709 PM CDT Tue Apr 12 2022 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...Satellite and radar images as well as surface observations indicate scattered showers and thunderstorms across portions of northeast Mexico early this evening with high level clouds from the storms moving across southern and eastern portions of deep south Texas (mainly Cameron, Willacy and Hidalgo counties). In addition...low to mid level clouds continue across portions of the Rio Grande Valley. Ceilings were near 1400ft at KPIL to near 3000ft at KMFE. Visibilities were near 6SM with haze at KBRO. Expect MVFR conditions to prevail across the Rio Grande Valley tonight into early Wednesday morning as a 500mb shortwave trough across northeast Mexico moves eastward tonight providing an increase in low to mid level moisture across the area. This will provide showers or thunderstorms in the vicinity of local aerodromes this evening. In addition...low clouds and haze will reduce ceilings/visibilities across the RGV tonight. Last but not least...a strong low level jet along the lower Texas coast will provide some low level wind shear across portions of the Rio Grande Valley late tonight into early Wed morning as the surface winds decouple with the stronger winds aloft with the loss of diurnal heating. && .PREV DISCUSSION... /issued 311 PM CDT Tue Apr 12 2022/ SHORT TERM (Now through Wednesday Night): First off, congrats to those who picked up a little rain this morning! It wasn`t much (less than 0.05" everywhere) , but we`ll take any thing we can get after a month or more of no rain in a number of locations. There were also a few reports of pea-sized hail within the stronger storms this morning, which makes sense given the dry mid-levels and steep mid- level lapse rates over 8.5 C/km that were shown on the 12Z sounding at KBRO this morning. Aloft, an H5 shortwave is currently moving over northern Mexico with another impulse of energy coming off the Sierra Madre Oriental already (as of 2:45 PM CDT) sparking some showers and storms near Monterrey, Mexico. As the impulse moves closer to the County Warning Area (CWA) tonight, it should help sustain those showers and storms as they come off the mountains. A few wrinkles to that is a stout CAP (temperature inversion) between 925 & 850mb along with the very dry mid-levels indicated on the special 18Z sounding we did for PERiLS. These could limit how widespread the showers and thunderstorms could be as they near the CWA later tonight. That said, I leaned pretty hard on the Convection Allowing Models (CAMs), which did handle this morning`s rain/convection fairly well, for tonight`s forecast. As it stands now, the best chance for rain this evening will be in the Rio Grande Valley. The current timing has showers/storms entering around 5-6PM CDT for Starr County and an hour or so later for the rest of the Valley as everything lifts in from the southwest. The Storm Prediction Center (SPC) has placed areas west of I-69C under a Marginal Risk of severe weather with their latest update. The greatest threats for severe storms will come from hail and damaging winds. Areas east of I-69C could see stronger storms this evening as well, just confidence is a bit higher out west. Additionally, the last several runs of the HRRR have shown the potential for a wake low forming behind the cluster of showers and storms it has moving through the area. This is due to the dry mid- levels in place evaporating the rain aloft, which then cools the air in the mid-levels and allows it to rush to the surface and produce strong, gusty winds. Not super confident in this, but wanted to mention it as a possibility. That`s all tonight... Wednesday will see a dry line advance westward in the afternoon ahead of a cold front that will eventually catch up to it. Areas west of the dry line, which should make it to roughly the I-69E/US-77 corridor, could see temperatures climb above 100 degrees while those near the coast "only" top out in the middle to upper 90s. This is a similar set up to last Wednesday, but some morning clouds and slightly lower 850mb temperatures *should* keep areas from spiking too high. Key word there... Should. The cold front stalls along the coast Wednesday night and will get pushed inland as the night progresses. So, while overnight temperatures are expected to be a bit cooler Wendesday night, they`ll still drop to near normal. LONG TERM (Wednesday Night through Tuesday):The northern jet stream retreats northward for the middle and latter half of the week as northern edge of the Subtropical Ridge builds over Mexico edging into South Texas. Two storms systems pass along and just south of the Canadian border one the end of the work week and a second more southern one next Monday and Tuesday. This in turn will result in an overall reduction in the wind speeds with a more gentle to moderate breeze and higher relative humidity to reduce the fire danger for the long term. The first mid-level low pressure system looks to have enough energy to push a trailing cold front into the region Thursday but lifting back north Friday. Low level moisture and increasing pwats in the 1.7-1.9 inch range may lead to some isolated showers. NBM remains dry in this period while the GFS/EC still show limited QPF. Confidence is low but will leave the current low end pops in for Friday morning and add some in Thu night for good measure with the front draped over the region. The weekend looks fair with the subtropical ridge reaching its apex and a light to moderate Gulf breeze. Highs Thu- Sunday in the 80s to mid 90s and possibly a few lower 100s far west on the weekend. Lows remain mild in the 60s to around 70 along the Rio Grande. Next week a stronger mid-level low moves across the Great Lakes and Midwest. A stronger front works its way south but there is uncertainty if it moves through the RGV. ECMWF remains strongest with the front with the GFS lagging on it southward push. There is a lot of uncertainty on how this front plays out with the overall chance of rain. NBM indicates rain chances increasing Monday and lingering Tuesday while the 12/12Z GFS and 11/00Z ECMWF are not in total agreement with this. Moisture does pool and increase around the front so will go with the low end pops that the NBM suggest for now. Monday`s highs will be in the upper 80s and 90s with limited cooling in the low to mid 80s Tuesday if the front makes it into the region. MARINE (Now through Wednesday Night)...Adverse marine conditions continue along the Lower Texas Coast for much of the period. Breezy to gusty conditions are expected on the Laguna Madre the rest of the afternoon through 6 AM CDT Wednesday. Meanwhile, seas on the Gulf waters remain very high with the latest observation at Buoy 42020 showing seas of around 7 feet. Elevated seas and occasional winds above 20 knots are expected through Wednesday night, where the Small Craft Advisory has been extended now until 1 AM CDT Thursday. Also, a complex of showers and thunderstorms are expected this evening into the overnight hours. Gusty winds (in excess of 35 knots), lightning, and small hail will all be possible within any of the thunderstorms along the Lower Texas Coastal waters tonight. Thursday through Sunday...Fair marine conditions are expected late this week and over the weekend. A weak cold front works into the Lower Texas Gulf waters Thursday before returning north Friday. Moderate northeast to east winds may be strong enough to warrant short duration Small Craft Advisories Thursday with more tranquil conditions Friday. Weak high pressure builds across the eastern Gulf and Friday`s retreating front pulls up stationary across the Gulf South maintaining a light onshore flow for the lower coast. Seas will tend to be on the moderate to low side. FIRE WEATHER (Wednesday): Critical fire weather conditions are expected Wednesday due to a dry line/cold front combo that will be pushing in from the west. This will drop relative humidity values to between 8 to 25 percent for all of the Brush Country, Rio Grand Plains, and the Mid/Upper Rio Grande Valley and western portions of the Brooks/Kenedy Ranches in the afternoon. 20-foot winds are forecast to increase and start coming out of the northwest behind the dry line. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 74 94 69 82 / 40 0 0 10 BROWNSVILLE 75 98 71 87 / 40 0 0 10 HARLINGEN 74 100 68 87 / 40 0 0 10 MCALLEN 74 103 69 92 / 40 0 0 10 RIO GRANDE CITY 74 104 68 95 / 20 0 0 0 SOUTH PADRE ISLAND 73 82 70 75 / 40 0 0 10 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...High Rip Current Risk through Wednesday evening for TXZ451-454- 455. Red Flag Warning from noon to 7 PM CDT Wednesday for TXZ248>250- 252-253-353. GM...Small Craft Advisory until 6 AM CDT Wednesday for GMZ130-132-135. Small Craft Advisory until 1 AM CDT Thursday for GMZ150-155-170- 175. && $$ This product is also available on the web at: 61-Castillo/69-Farris/67-Mejia
Area Forecast Discussion
National Weather Service Corpus Christi TX
1007 PM CDT Tue Apr 12 2022 .MARINE... The HRRR and RAP indicated winds increasing through midnight with gusts to gale force. Buoy020 reported gusts to 35 knots and MSAS analysis indicated a meso-high has developed in response to convection earlier in the evening near BROs area. Therefore, have gone with a Gale Warning through 5 AM Wed for frequent gusts to gale force. This includes the nearshore waters south of Port Aransas and the offshore waters out to 60NM. && .PREV DISCUSSION... /Issued 657 PM CDT Tue Apr 12 2022/ AVIATION... MVFR conditions due to CIGs and patchy light fog are expected to develop across the eastern TAF sites through the evening then spreading west with brief MVFR conditions across LRD and COT overnight into early Wed morning. Brief IFR CIGs are possible across VCT toward early Wednesday morning. A low level jet will strengthen to 40-45 knots overnight, but elevated surface winds across most areas should preclude LLWS, except COT where surface winds are expected to be lowest. A dryline will move east through the day Wed resulting in winds shifting to the west then northwest as the dryline approaches the coast. The dryline is expected to retreat westward by late afternoon with winds along the coast clocking back around to the east. Wind gusts to around 25kt will be possible beginning mid morning Wed. All TAF sites winds are expected to be easterly and weaker Wed evening. PREV DISCUSSION... /Issued 335 PM CDT Tue Apr 12 2022/ SHORT TERM (Tonight through Wednesday Night)... A look at water vapor imagery this afternoon reveals a shortwave ejecting out of Mexico. This has led to isolated showers and storms through the afternoon across the Coastal Plains and Victoria Crossroads. A few of these storms have been on the stronger side with small hail being the main threats. Our 18Z sounding hints at a weakening cap and a substantial amount of instability. This is also evident by the well defined field of ACCAS moving across the Coastal Plains. Any additional convection that fires up this afternoon would have the potential to near severe limits with large hail and damaging winds the main hazards. With that said, models continue to show another upper level shortwave rotating across the region late this afternoon and evening. Another round of showers and storms are possible as this disturbance moves through. Recent CAM guidance keeps the bulk of the activity to our south where the greatest forcing will be. However, the 12Z runs of the ARW and FV3 showed some activity across our northern counties this evening. Overall confidence in that solution is not too high but would not be surprised to see anything develop along a lingering outflow boundary. Any activity that does develop this evening looks to push offshore by 03Z. A low level stratus deck looks to build back in tonight as a ~40 LLJ ushers moisture across the region. After a mild and breezy night, the main story on Wednesday will be our critical fire weather concerns. A dryline will mix across the region on Wednesday ahead of an approaching cold front and associated upper level trough. It`s possible we see some isolated showers and potentially a storm or two ahead of the dryline where low level moisture convergence will be maximized. Critical fire weather conditions are possible behind the dryline as it stalls across the Coastal Plains (see fire section for more). As the dryline begins to retreat back to the west late Wednesday afternoon, a cold front will pick it up and eventually stall across the CWA. The boundary will eventually begin to push back north by Thursday morning. LONG TERM (Thursday through Tuesday)... Zonal flow aloft on Thursday will transition to a building mid to upper level ridge by the weekend. Moisture will begin recovering through the day on Thursday as a surface high pressure lifts to the northeast, allowing for the surface flow to gradually become onshore. Precipitable water values are progged to then increase to around 1.7 to 1.8 inches on Friday, which combined with lift and instability provided by a passing weak mid level disturbance could result in a few showers and/or thunderstorms over the region. Drier conditions are expected to develop heading into Friday night and will generally continue through the weekend as ridging then takes a hold. Rain chances may return to the forecast early next week as weak troughing develops aloft while it drags a few more passing disturbances along. At this time have opted for closely following the output from the NBM for Monday through Tuesday next week in terms of precipitation chances, as the mid range models continue to disagree on the amount of moisture available by then and also on the possibility of another frontal boundary moving through. With that said, have capped PoPs at the slight category. Other than the potential slight chances for rain through the period, the Extended forecast will feature increasingly warmer temperatures, particularly over the weekend. Highs on Saturday and Sunday are forecast to reach into the triple digits for portions of the Brush Country and Rio Grande Plains, with temperatures in the mid 80s to mid 90s elsewhere. These very warm temperatures along with high dewpoints could lead to a few hours of heat indices in the 100-105 range both days. If the aforementioned frontal boundary is able to push all the way trough the region early next week, then cooler temperatures may be in the cards for next Tuesday. MARINE... Onshore flow has steadily strengthened through the day and will remain elevated overnight. A Small Craft Advisory remains in effect for the bays through early tomorrow and through the early evening hours for the offshore waters. Onshore flow will weaken to more moderate levels through the day Wednesday. There is a slight chance for isolated showers and thunderstorms over the waters through the day tomorrow. Moderate to strong northeast to east wind is expected to develop again by mid morning Thursday and remain in place through Thursday night. Winds will shift to the south and southeast on Friday, with a moderate to at times strong onshore flow expected through early next week. Slight rain chances will be possible Friday and then again on Monday. FIRE WEATHER... Critical fire weather conditions are expected tomorrow across the Brush Country as a dryline mixes east. Very dry conditions are expected to settle in behind the dryline with RH values falling into the single digits. Although the winds may not specifically reach Red Flag Warning criteria, fuels are extremely dry and would easily lead to rapidly fire growth. In addition, the latest suite of the TFS maps places the Brush County under an Extreme Fire Danger Rating for Wednesday. The Coastal Plains falls under the Very High category. With that said, there may need to be an expansion further east with the RFW depending on how far the dryline shifts during the day. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 72 95 67 84 68 / 20 10 0 0 10 Victoria 71 93 59 87 65 / 20 20 0 0 10 Laredo 73 100 64 96 68 / 0 0 0 10 10 Alice 71 100 64 89 67 / 10 10 0 0 10 Rockport 72 87 67 81 69 / 20 20 0 0 10 Cotulla 72 100 58 97 68 / 10 0 0 0 0 Kingsville 72 99 66 87 68 / 10 10 0 10 10 Navy Corpus 71 85 69 79 69 / 10 10 0 0 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...High Rip Current Risk through Wednesday evening For the following zones: Aransas Islands...Calhoun Islands... Kleberg Islands...Nueces Islands. Red Flag Warning from noon to 7 PM CDT Wednesday For the following zones: Duval...Jim Wells...La Salle...Live Oak... McMullen...Webb. GM...Small Craft Advisory from 5 AM to 7 PM CDT Wednesday For the following zones: Coastal waters from Baffin Bay to Port Aransas out 20 NM...Waters from Baffin Bay to Port Aransas from 20 to 60 NM...Waters from Port Aransas to Matagorda Ship Channel from 20 to 60 NM. Gale Warning until 5 AM CDT Wednesday For the following zones: Coastal waters from Baffin Bay to Port Aransas out 20 NM... Waters from Baffin Bay to Port Aransas from 20 to 60 NM... Waters from Port Aransas to Matagorda Ship Channel from 20 to 60 NM. Small Craft Advisory until 5 AM CDT Wednesday For the following zones: Baffin Bay and Upper Laguna Madre...Copano, Aransas, and Redfish Bays...Corpus Christi and Nueces Bays...San Antonio, Mesquite, and Espiritu Santo Bays. Small Craft Advisory until 7 PM CDT Wednesday For the following zones: Coastal waters from Port Aransas to Matagorda Ship Channel out 20 NM. && $$ TE/81...SHORT TERM XX/99...LONG TERM
Area Forecast Discussion
National Weather Service Des Moines IA
659 PM CDT Tue Apr 12 2022 ...Updated for the 00z Aviation Discussion... .SHORT TERM.../Tonight through Wednesday Night/ Issued at 311 PM CDT Tue Apr 12 2022 Forecast Impacts for the week: ...Moderate Risk into Tonight ...Cooler Weather Returns ...Chances for Rain/Snow return into the weekend Confidence Short Term: Medium to High Overall the evolution of the system in both a synoptic and mesoscale space is still on track. The big question that is becoming a bit more clear is the northern location of the warm front around initiation time. Previous model runs have placed the front/triple point across far northwest Iowa (specifically the HRRR/GFS) as compared to the Euro. Today the HRRR is farther south with the boundary near 23z to 01z while the GFS is still closer to its previous forecast and farther north. At 19z, the boundary is just entering SW Iowa with a large shield of stratus and now elevated convection over Iowa into MN with the stronger storms into southern MN. Recent HRRR runs have shown that any stronger convection that may develop over the north is now more focused nearer the US20 corridor, rather than the IA MN border. With that in mind, the current moderate risk for that portion of the forecast appears well placed and the westward extension back into west Iowa remains for the area of secondary development expected along the dry line in the evening from 01 to 02z across the west. Without going into great detail, forcing and shear parameter space is is on the middle to high end of the spectrum. With SBCAPE over 3200 j/kg into the early evening along the retreating warm front and 0-1km SRH over 300 to 500 m2/s2 and long hodographs, there remains a potential for discrete supercells and a strong and relatively longer lived tornado or two in that area. If storms develop slightly north of the warm front, then a large hail threat would likely dominate the mode. Any supercells that develop will move northeast/east with time along or near the warm front. As the dry line now in central Nebraska will edge east and fire off a line of storms into our west by 01z. The line of storms is anticipated to strengthen quickly to severe levels and then slowly weaken as it moves toward the I35 corridor in central and southern Iowa. These storms later in the evening will have a somewhat less potential to be tornadic, but a severe wind threat and hail threat will continue. The northern portion of the line may have an opportunity to tap into the strong 0-3km shear and continue to have a tornado threat through at least the early morning hours. This area would more likely be along and north of US20. As the synoptic low drives northeast, a weaker surge of west northwest winds will move over the region tomorrow with colder air. Lows tonight will drop to the mid 30s west to the lower 50s east. Highs tomorrow will be in the 40s to around 50. && .LONG TERM.../Thursday through Tuesday/ Issued at 311 PM CDT Tue Apr 12 2022 Confidence: Medium The remainder of the forecast will be dominated by dry weather through Saturday with a chance of rain and snow Sunday. We continue with northwest flow and cool weather into the remainder of the extended with little warming. Highs will remain in the 40s and 50s with cool April highs during the remainder of the forecast. && .AVIATION.../For the 00Z TAFS through 00Z Wednesday evening/ Issued at 642 PM CDT Tue Apr 12 2022 Main aviation concerns continue to be storms and wind, especially in the next few hours of the TAF cycle. Storms could gust to severe limits in addition to dropping ceilings and visibilities into MVFR or even brief periods of IFR. Additionally, low-level wind shear is expected into the early overnight hours and gusty winds of the south, shifting to be out of the west to northwest, will remain into tomorrow behind an approaching cold front. Storms/showers expected to end west to east during the overnight hours, roughly between 09-12Z, with VFR conditions returning gradually to all TAF sites by about mid morning. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...REV LONG TERM...REV AVIATION...KCM
Area Forecast Discussion
National Weather Service Quad Cities IA IL
637 PM CDT Tue Apr 12 2022 ...AVIATION UPDATE... .SYNOPSIS... Issued at 254 PM CDT Tue Apr 12 2022 A warm front is lifting north into the CWA as of 2 PM, and our 18Z upper air sounding shows this taking place. As forecast, there is a very steep layer of mid level lapse rates, but though steep, there is very little moisture within that layer. A strong EML exists above the lowest thousand feet, which means the impressive shear found from the surface to 3500 ft is not able to be accessed by updrafts this afternoon. && .SHORT TERM...(This Evening through Wednesday) ISSUED AT 254 PM CDT Tue Apr 12 2022 Tonight, the timing of the squall line arrival remains very late in the evening west to around 6 AM in our Illinois counties. This late arrival coincides with consistent model data showing waning instability, decaying storm organization. Strong shear values continue through early morning which should be something that really stays going ahead of the front through tomorrow. In case, I find little reason to deviate from the ongoing high pop forecast in our northwestern counties around Midnight, then translating east as a likely pop approaching the Mississippi River, then chance east. QPF will be relatively low, generally less than 0.25". I`ll continue to advertise the severe gust potential with the decaying squall line, but this threat for severe will greatly lower as the sees increasingly back sheared tilted updrafts with quick eastward motions resulting in sputtering updraft strength. Highs Wednesday for most locations will occur between Midnight and 8 AM, as CAA increases with low stratus in place behind the decayed line. Another wave of moisture and some MUCAPE will bring rain and embedded thunder to the area during the day Wednesday. A cold rain is expected in most spots, but the far east could see a downdraft with winds over 50 mph, should surface heating early in the day coincide with secondary wave. Right now, it looks like precipitation will overspread the entire area during the late morning, and then gradually end from west to east during the late afternoon. Afternoon wind chills in the upper 30s to lower 40s will be found west of the Mississippi River. Brrr! .LONG TERM...(Wednesday Night through Tuesday) ISSUED AT 254 PM CDT Tue Apr 12 2022 Key messages: 1. Windy day on Thursday. 2. Cooler temps through the period. 3. Clipper into the weekend is next chance for QPF across the area. Discussion: Upper level pattern changes from zonal to NW a few times through the long term period as storm track is north of the area. Reinforcing shots of cold air keep us on the cooler side of average as we see highs in the 40s to low 50s. Nighttime temps in the 30s near freezing may be the more important forecast parameter as chances for snow or frost/freeze seem to be the main thing of hazard after Thursday`s winds. Thursday, guidance continues to have lower wind gusts than earlier in the week. We are just getting into CAM data, and the NAMnest continues the sub 40 knot wind gusts and more like a low to mid 30 gust potential. The 12z HRRR has stronger winds than most guidance across S MN as the upper low moves in, so will need to keep an eye on this to see which way it trends. My initial guess is that the HRRR, may be better at gust forecasts for this event as it usually does a better job with mixing and wind gusts. Still plenty of time to analyze this threat as we are 40 some hours out from when it would start. After this, a clipper that moves across the northern CONUS will bring a chance for precip late in the weekend. With temperatures near or below freezing we could see some frozen precip. Confidence in this occurring is low. We are right on the cusp for frost/freeze headlines and will keep a close eye on vegetation. This may be the larger threat after Thursday. Confidence in this occurring is also low. && .SHORT TERM...(This Evening through Wednesday) ISSUED AT 254 PM CDT Tue Apr 12 2022 Tonight, the timing of the squall line arrival remains very late in the evening west to around 6 AM in our Illinois counties. This late arrival coincides with consistent model data showing waning instability, decaying storm organization. Strong shear values continue through early morning which should be something that really stays going ahead of the front through tomorrow. In case, I find little reason to deviate from the ongoing high pop forecast in our northwestern counties around Midnight, then translating east as a likely pop approaching the Mississippi River, then chance east. QPF will be relatively low, generally less than 0.25". I`ll continue to advertise the severe gust potential with the decaying squall line, but this threat for severe will greatly lower as the sees increasingly back sheared tilted updrafts with quick eastward motions resulting in sputtering updraft strength. Highs Wednesday for most locations will occur between Midnight and 8 AM, as CAA increases with low stratus in place behind the decayed line. Another wave of moisture and some MUCAPE will bring rain and embedded thunder to the area during the day Wednesday. A cold rain is expected in most spots, but the far east could see a downdraft with winds over 50 mph, should surface heating early in the day coincide with secondary wave. Right now, it looks like precipitation will overspread the entire area during the late morning, and then gradually end from west to east during the late afternoon. Afternoon wind chills in the upper 30s to lower 40s will be found west of the Mississippi River. Brrr! .LONG TERM...(Wednesday Night through Tuesday) ISSUED AT 254 PM CDT Tue Apr 12 2022 Key messages: 1. Windy day on Thursday. 2. Cooler temps through the period. 3. Clipper into the weekend is next chance for QPF across the area. Discussion: Upper level pattern changes from zonal to NW a few times through the long term period as storm track is north of the area. Reinforcing shots of cold air keep us on the cooler side of average as we see highs in the 40s to low 50s. Nighttime temps in the 30s near freezing may be the more important forecast parameter as chances for snow or frost/freeze seem to be the main thing of hazard after Thursday`s winds. Thursday, guidance continues to have lower wind gusts than earlier in the week. We are just getting into CAM data, and the NAMnest continues the sub 40 knot wind gusts and more like a low to mid 30 gust potential. The 12z HRRR has stronger winds than most guidance across S MN as the upper low moves in, so will need to keep an eye on this to see which way it trends. My initial guess is that the HRRR, may be better at gust forecasts for this event as it usually does a better job with mixing and wind gusts. Still plenty of time to analyze this threat as we are 40 some hours out from when it would start. After this, a clipper that moves across the northern CONUS will bring a chance for precip late in the weekend. With temperatures near or below freezing we could see some frozen precip. Confidence in this occurring is low. We are right on the cusp for frost/freeze headlines and will keep a close eye on vegetation. This may be the larger threat after Thursday. Confidence in this occurring is also low. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening) ISSUED AT 629 PM CDT Tue Apr 12 2022 Low-level wind shear of 50+ kts and MVFR clouds are expected overnight, along with a weakening line of showers and thunderstorms arriving late. Periods of IFR are possible especially in pockets of brief moderate/heavy rain. Gusty S to SSE winds will continue into early Wednesday AM before switching to the WNW behind a cold front. Another round of rain is expected from around midday Wednesday through the afternoon, which could be moderate to briefly heavy at times at BRL and MLI. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...Ervin SHORT TERM...Ervin LONG TERM...Gibbs AVIATION...Uttech
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
752 PM CDT Tue Apr 12 2022 .UPDATE... Severe thunderstorms have moved out of our CWA and we do not expect any more severe storms to develop tonight. We have cancelled the Tornado Watch for all of the counties in our CWA. && .PREV DISCUSSION... /ISSUED 735 PM CDT Tue Apr 12 2022/ AVIATION... /00Z TAFS/ Dry-line to retreat west this evening and moderate the near record temps along and west of I-35. Dew points in the low 70s over the Coastal Prairies should help with drawing surface temps down to where a low level cig should form, but it will probably not happen until around midnight. With upper troughing still to the west, we`ll see the overnight winds stay up and even be gusty to near 20 knots at times. This should point to the cigs staying in the MVFR levels. No convection is expected as the CAP is supposed to strengthen, but a few streamer showers can`t be ruled out. Clouds should get kicked out by around 15Z when the Pacific front arrives and kicks up the wind gusts up to around 25 knots again. PREV DISCUSSION... /ISSUED 423 PM CDT Tue Apr 12 2022/ UPDATE... Thunderstorms have begun to form along the dryline and will continue to move toward the northeast. Low level wind shear is quite strong in the warm airmass to the east. Supercell thunderstorms will be possible as the dryline moves into this warm air and some storms could be severe. While large hail is the most likely threat, tornadoes will also be possible and SPC has issued a Tornado Watch for Burnet, Blanco, Hays, Travis, and Williamson Counties until 11 PM. PREV DISCUSSION... /ISSUED 208 PM CDT Tue Apr 12 2022/ SHORT TERM (Tonight through Wednesday Night)... Bottom line: confidence in storms developing somewhere in the area is higher than it was this morning. However, coverage is still expected to be widely scattered so not every location will be impacted. The forecast remains on track today with a somewhat diffuse dryline beginning to push across the Rio Grande just after 18Z, just a bit behind an H5 shortwave evident in water vapor imagery and RAP analysis that was over the Rio Grande Plains. Behind the dryline, we`ll see RH dip into the teens and winds increase to 10-15 mph, and a Red Flag Warning remains in effect for our western counties through 9pm. One small storm on radar clipped our far southeastern counties early this afternoon, but otherwise skies are now clear west and continue to clear out east. If the dryline can tighten up the Td gradient a bit and advance east, it`s ascending branch would easily mix out our capping inversion in tandem with the mid-level PVA-induced lift moving through. ACARS soundings and the 18Z DRT RAOB indicate the cap continues to weaken but is not quite fully eroded. With storms developing to our north from Menard to Runnels counties, we are gaining confidence that storm development is imminent somewhere in our area soon. Not 100% confident just yet, but we anticipate storms are likely to develop somewhere in the area between the longitudes of Rocksprings and Austin between 2:30-6pm. If they do they`ll have 3kJ/kg to work with along with increasing deep layer shear near 40 knots. Mainly discrete, supercellular modes are favored initially, and large to very large hail will be the primary risk should storms develop, with damaging winds also possible. However, there is also a low-end threat for tornadoes, particularly over our far northeastern counties. Should storms develop, they`ll likely be moving across the highly populated I-35 corridor during the evening rush hour before exiting our area to the east by 9pm. The warm, moist airmass will remain in place overnight. Expect the cold front to move in through the morning hours Wednesday. There is a very low chance for frontal showers or perhaps a storm in the morning over our far northeastern areas, but most guidance keeps this activity out of our area. That said, can`t completely rule out an isolated severe storm in the morning along the US-77 corridor. Winds shift to the NW and advect in much drier air behind the front as well as clear skies. With temperatures not too much cooler, (highs still in the 80s and 90s), RH will likely dip into the single digits for many areas Wednesday afternoon. Winds will increase to 15- 22 mph over western and northern portions of the area and 10-18 mph for the Coastal Plains during the day gusts as high as 25-30 mph may occur along and west of I-35 for a few hours. Will hold the Fire Weather Watch as is for now but it will be upgraded to a Red Flag Warning after today`s expires. Winds drop off quickly during the evening and we`ll have some more comfortable lows by Thursday morning in the upper 40s north and 50s elsewhere. LONG TERM (Thursday through Tuesday)... A zonal flow aloft is forecast to prevail across the area from Thursday into Saturday. By Saturday afternoon into the evening, the flow shifts to the northwest and pushes a series of disturbances over our area. At the surface, an east to southeast wind is forecast for Thursday and shifting to the southeast and south during the day on Friday as a surface high pressure ridge develops across the region. The GFS solution likes to bring light QPF across the coastal plains and southeast counties on Friday afternoon while the ECMWF brings a cluster of storms across the Burnet and Llano Counties. The NAM is dry while the Canadian shows light QPF across the coastal plains during the morning period. Due to the uncertainties shown by the models, we are going for a slight chance for showers and storms mainly for areas southeast of Interstate 35. Dry weather conditions continue into the first part of the weekend. However, there is a lot of uncertainties during the Saturday and Sunday time frame. And here is why. The GFS pushes the frontal boundary across the Hill Country on Saturday afternoon with some light QPF across the Edwards Plateau and western Hill Country. The ECMWF and Canadian solutions keep the area dry with the boundary remaining to our north. By Sunday morning, the GFS pushes back the boundary to the north while the ECMWF and Canadian models push the frontal boundary to the south and into the Hill Country. So, this coming weekend could be dry for some people with some communities getting lucky with much needed rain. Rain chances continue on Monday and Tuesday as a stronger frontal boundary signal is evident in all medium range models. As far as temperatures go for later in the week into the weekend expect highs in the 80s and 90s on Thursday through Sunday and near 100 across the southwest on Saturday and Sunday afternoons. FIRE WEATHER... Fire weather concerns still in place for Thursday as near critical to critical weather exist for areas along and west of Highway 183. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 70 92 53 86 61 / 20 20 0 - - Austin Bergstrom Intl Airport 71 92 51 86 60 / 20 20 0 - - New Braunfels Muni Airport 71 94 52 88 61 / 20 - 0 - - Burnet Muni Airport 68 89 50 85 61 / 20 10 0 0 - Del Rio Intl Airport 67 92 55 92 66 / 0 0 0 0 0 Georgetown Muni Airport 71 92 50 85 59 / 20 20 0 0 - Hondo Muni Airport 69 95 52 92 61 / 10 0 0 - - San Marcos Muni Airport 69 94 51 88 60 / 20 20 0 - - La Grange - Fayette Regional 72 91 56 86 63 / 20 30 0 - - San Antonio Intl Airport 71 94 55 88 63 / 10 0 0 - - Stinson Muni Airport 72 98 57 91 65 / - 0 0 - - && .EWX WATCHES/WARNINGS/ADVISORIES... Fire Weather Watch from Wednesday morning through Wednesday evening for Atascosa-Bandera-Bexar-Blanco-Burnet-Comal-Dimmit-Edwards-Frio- Gillespie-Guadalupe-Hays-Karnes-Kendall-Kerr-Kinney-Llano-Maverick- Medina-Real-Travis-Uvalde-Val Verde-Williamson-Wilson-Zavala. Red Flag Warning until 9 PM CDT this evening for Dimmit-Edwards- Kinney-Maverick-Real-Uvalde-Val Verde-Zavala. && $$ Short-Term/Aviation...Oaks Long-Term...05 Decision Support...Treadway
Area Forecast Discussion
National Weather Service Grand Rapids MI
904 PM EDT Tue Apr 12 2022 LATEST UPDATE... Update .UPDATE... Issued at 903 PM EDT Tue Apr 12 2022 It would seem to me that showers should be developing over central Lake Michigan within the hour and those showers should quickly develop into scattered thunderstorms. I would also think there is a good chance for small hail (less than 1 inch) from these storms as mid level lapse rates (700 to 500 mb) are expected to be in the range of 7 to 8.5c (23z HRRR). There is also decent low level jet, centered southwest of Chicago for severe hours before it begins to weaken and drift ESE toward western Ohio around 5 am. Between midnight and 3 am there is 60 to 65 knot speed max southwest of Chicago with a 20 to 30 knots of speed convergence over the west Central CWA during that time. Moisture transport vectors are pointed northeastward into Southwest Michigan. There is between 500 and 1000 j/kg of mid level cape in the midnight to 5 am time frame over most of Southwest Michigan. On the other hand we have condensation pressure deficits in the 8000 to 1200 ft layer between 50 and 80 mb (to dry for clouds) in that layer. So my thinking is this will be somewhat like 2 nights ago. We will see scatted storms develop that move quickly northeast around 40 mph. Many of these storms will produce small hail. Gusty winds are possible given the 700 j/kg of dcape but there is a decent low level inversion so it may be hard to mix that down to the ground. The bottom line is I do not expect severe storms but I do expect some thunderstorms, mostly north of I-96 in the 11 pm to 4 am time frame. They will be most active north or Route 20 in the 1 am to 3 am time frame. There will then be a break in the convection after that until the southern stream shortwave convection arrives after sunrise. && .DISCUSSION...(This evening through next Tuesday) Issued at 207 PM EDT Tue Apr 12 2022 - Thunderstorms developing tonight A surface warm front down in the mid MS river valley will lift northward into lower MI tonight. An 850 mb low level jet arrives here in MI as the front approaches along with elevated instability. Showalter indices of -2 to -4 are predicted around midnight. Scattered thunderstorms are expected to develop and increase as the front and jet track through the region with northern zones likely to see the most coverage of thunderstorms. Mid level lapse rates steepen up and deep layer shear values are over 40 there is some potential for hail out of the thunderstorms. The steepest lapse rates are shown to occur across our northern zones...around Route 10. We will continue to hold on to high POPs north of the Muskegon to Lansing area for tonight. - Slight chance for severe weather Wednesday into Wednesday night The models show the stronger deep layer shear setting up north and west of the CWA to start the day. After 22z is when the shear starts to increase steadily from the west. SPC HREF surface based CAPE values are shown to remain under 1000 J/kg through the day. A mid level vort max moves in from the southwest for the late morning to early afternoon hours...which may support one round of storms. Given the relatively low CAPE forecast and limited deep layer shear...any severe weather for middle part of the day would appear to be isolated. The surface front arrives overnight with strengthening deep layer shear. The instability is shown to be diminishing. However stronger dynamics start to move in along the approaching frontal zone as a potent mid level vort max lifts up from the southwest. The flow aloft becomes highly diffluent as well. How much if any severe weather we see will be impacted by how much instability will be around. Thus timing will be important. If storms do develop...they could feature some severe weather given the stronger dynamics and shear that will be in place. Our convective setup for Wednesday will be impacted by how the pattern evolves changes are possible. - Heavy rain possible While the storm motion will be relatively fast...models are showing the risk for multiple rounds of storms. The last couple of runs of the HRRR show some swaths of over 2 inches and WPC has the area under a marginal risk for excessive rain. As a result the potential for urban and poor drainage flooding exists. - Possible wind impacts Thursday Bufkit overviews from the NAM and GFS show deeper mixing developing on Thursday across the CWA. Mixing heights top out around 40 to 45 knots which could translate to surface gusts around those values. These winds would be high enough to cause some power outages. We will continue to highlight this risk in social media posts and in messaging. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 748 PM EDT Tue Apr 12 2022 Currently skies are partly cloudy with mid and high clouds across the GRR TAF sites at 730 pm. However there is a warm front to our south pushing in our direction. There is a band of MVFR and some limited IFR (as would be typical) close to the warm front over IN,IL and eastern OH. There is currently no convection on the warm front. However there is a active area of showers and a few thunderstorms across NE WI, that are heading east northeast. Those storms would pass north of Route 10 in central Lower Michigan if the continue to track as they are doing now. As I stated above, for the most part the showers and thunderstorms over WI and now moving toward northern Lake Michigan, should spread into northern Lower Michigan by 01z to 03z. It would not be out of the question for a storms to develop a touch father south in the 03z to 06z time frame. If that does happen the northern TAF sites are more likely to see them than are the southern TAF sites. Small hail is possible from the stronger storms. Again if they happen, they should be out of the TAF sites in the 06z time frame. Meanwhile that area of MVFR/IFR cigs will head this way and reach our TAF sites in the 03z to 05z time frame. Once they move in they will remain around through Wednesday evening. Winds will be very strong above the surface tonight. 50 knots will get as close as 1000 ft AGL by 06z so I have continued the low level wind shear in our TAFs tonight. Another area of showers and few thunderstorms is expected for late Wed morning into early evening. MVFR/IFR conditions are expected at that time. The showers Wednesday afternoon should be widespread and impact all TAF sites. It would not be impossible for a few of the thunderstorms to become severe toward evening but the SPC SREF had only a 10 pct chance at that time. && .MARINE... Issued at 207 PM EDT Tue Apr 12 2022 A strong storm system will move into the marine zones over the next couple of days. One low level jet tracks in this evening and that will generate some stronger wind gusts along the lakeshore. Those gusty winds will continue through Wednesday as a strong cold front approaches from the west. The front tracks through Wednesday night and the cold air advection will strengthen on Thursday. This will result in deeper mixing and possible gales. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...Gale Watch from Thursday morning through Thursday evening for LMZ844>849. Small Craft Advisory until 8 AM EDT Thursday for LMZ844>849. && $$ UPDATE...WDM DISCUSSION...MJS AVIATION...WDM MARINE...MJS
National Weather Service Wilmington OH
1049 PM EDT Tue Apr 12 2022 .SYNOPSIS... Retreating high pressure will shift to the East Coast overnight. Unsettled weather returns Wednesday with a front bringing showers and thunderstorms. Above normal temperatures will drop to near normal readings late in the week behind the front. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Partly to mostly cloudy skies will continue through the night as lower clouds diminish but higher level clouds increase. South winds will persist and perhaps strengthen a bit overnight. Forecast lows look on track. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... A mid-level shortwave advancing northeast in deep southwesterly flow provides the impetus for showers and thunderstorms Wednesday... starting in the mid-morning over the Tri-State region and reaching central Ohio by late afternoon. Guidance generally agrees there will be a brief respite into the early evening hours, following by pre-frontal convection. Highs Wednesday will reach well into the 70s. Winds may gust to around 30-35 mph during peak heating. For Wednesday late evening into the overnight, there remains plenty of uncertainty on timing of a band of pre-front storms. Earlier timing such as the 12Z HRRR depicts would increase the chance of damaging wind gusts due to better instability. For now, have indicated a broad period of PoPs to cover this instability, and also have kept mention of damaging wind gusts due to clear indication on all the CAMs of a linear mode along with shear of 40-50 knots. Also kept mention of isolated tornado potential in the HWO due to expected QLCS-nature of the convection. Frontal passage is likely to occur after midnight behind the thunderstorm activity. This leads to dropping dewpoints and lows dipping into 40s by early Thursday morning. && .LONG TERM /THURSDAY THROUGH TUESDAY/... On Thursday morning, the aforementioned (rather large) low will be positioned over northeastern Minnesota with its associated cold front extending from Ontario down through the Appalachian mountains continuing through the Louisiana coast into the Gulf of Mexico. As the system continues to propagate off to the east, high pressure moves into the forecast area bringing dry conditions for the remainder of Thursday into Friday. Gusty winds will be the primary post-frontal concern Thursday morning. While deterministic guidance has been trending wind speeds/ wind gusts lower, still kept gusts between 25-30kts at start of Thursday as frontal boundary exits the area. As the day continues, a slightly tighter pressure gradient continues to sit over the northern half of the CWA so gusts between 20-25kts are expected in areas north of I-70 while winds in areas south are anticipated to decrease in intensity during afternoon hours. The closed low continues to slowly move east/northeast throughout this time frame and ejects mid-level vorticity around its southern base which could help force some pcpn Friday night into Saturday morning. Confidence here is lower, so kept slight pops throughout the CWA. After this upper level low moves out toward the Atlantic/ Nova Scotia area, northerly flow returns to our area and temperatures trend cooler than normal for the next several days. Saturday highs reach low 60s in the southern CWA and mid 50s in the north. Sunday trends even cooler, with highs in the mid to low 50s for the majority of our area. In fact, there is a signal for frost in parts of our western counties Sunday morning as low temperatures dip to mid/low 30s in spots combined with light wind and clearer skies. Pcpn chances ramp up again near the end of the weekend as a larger wave of energy begins to work its way into the area from our west. Unfortunately, model guidance varies quite a bit during this time, both in terms of location and timing. Therefore, have kept chance pops in grids until better agreement between models. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... VFR will prevail through the night and well into Wednesday morning. Winds will increase to 10 to 15 kt overnight and then strengthen further after 13Z with gusts over 25 kt at times. A couple of areas of showers are forecast to move northeast across the region. Fair amount of uncertainty with timing/coverage. Initially expect conditions to remain VFR but as low levels moisten, ceilings will fall to MVFR, likely dropping below 2kft for a period of time late in the period. There could be some embedded thunder within these showers and there could be a drop in visibility as well. OUTLOOK...Thunderstorms are likely Wednesday night, potentially producing very strong wind gusts. After the thunderstorms move through, MVFR ceilings are possible late Wednesday night into Thursday morning. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM...CA AVIATION...
Area Forecast Discussion
National Weather Service Lincoln IL
816 PM CDT Tue Apr 12 2022 .SYNOPSIS... Issued at 805 PM CDT Tue Apr 12 2022 Windy and warm conditions will prevail across central Illinois tonight...with a few showers developing toward dawn. Strong to severe thunderstorms will be likely Wednesday afternoon and evening, especially for locations east of the Illinois River. && .UPDATE... Issued at 816 PM CDT Tue Apr 12 2022 A warm front continues to lift northward through central Illinois early this evening, with winds veering to S/SE and gusting 25 to 35mph. With only weak upper forcing in place, the front has not generated any showers thus far and is not expected to do so for the remainder of the evening. Meanwhile further west, a line of thunderstorms has developed along a dryline across eastern Iowa into north-central Kansas. These storms will track E/NE as the night progresses and may spill into the Illinois River Valley in a greatly weakened state toward dawn. In addition, a short-wave trough currently over the Lower Mississippi River Valley will trigger scattered showers/thunder as it lifts northward into the Ohio River Valley late tonight. Have continued to go with a dry forecast until after 08z/3am when showers/storms begin to spread into the SE KILX CWA...then after 10z/5am when scattered showers arrive in the Illinois River Valley. High chance to likely PoPs will be focused along/south of a Paris to Shelbyville line by daybreak...with low chance PoPs elsewhere around the area. && .SHORT TERM...(This evening through Wednesday) ISSUED AT 259 PM CDT Tue Apr 12 2022 Afternoon water vapor imagery reveals a couple waves that will bring multiple rounds of showers and thunderstorms to central Illinois through Thursday evening. This afternoon, a shortwave trough is noted over central TX and is progged to lift northeast across southern Illinois by early Wednesday morning. Showers and perhaps a few storms will be possible with this initial wave over portions of SE and east central Illinois, though instability will be weak during that time frame and convection will remain elevated limiting any severe threat with this initial wave of precip. Meanwhile, a strong upper wave is over south central Montana this hour while a deep surface low is analyzed over central Nebraska. The surface low is progged to move slowly ENE across southern Minnesota overnight with a trailing cold front pushing across Iowa and Missouri where a line of strong to severe thunderstorms will develop. This line of storms is expected to approach the Illinois River Valley early Wednesday morning in a decaying state given the time of day. Remnant showers and possibly a few non-severe storms are expected to move across central Illinois through the morning. The extent and exact timing of this initial round of precip from both the cold front and the southern stream wave will need to be closely monitored as it will delay recovery of instability through the day Wednesday which comprises the primary area of uncertainty with respect to the severe threat that will develop later in the day. The cold front is expected to push from the Illinois River Valley towards the I-55 corridor through the early to mid afternoon hours. With strong moisture transport due to favorable trajectories off the Gulf of Mexico, dew points are expected to surge into the 60s Wednesday as very steep lapse rates associated with an elevated mixed layer overspread central Illinois. Guidance suggests that 800-500mb lapse rates will exceed 8 C/km at times Wednesday afternoon which will contribute to MLCAPE values pushing possibly as high as the 1500-2500 J/kg range if all these ingredients come together. As mentioned earlier, the amount of recovery will be the big question mark through the day given the morning round of precip and cloud cover early in the day. A number of models are much more conservative on the amount of destabilization, with CAPE values topping out more in the 500-1000 J/kg range. Despite uncertainty in the amount of instability, there is high confidence in strong deep layer shear exceeding 50 kt with much of this focused in the lowest 3-km. With these ingredients in place, storms are expected to redevelop along the cold front Wednesday afternoon and quickly grow upscale as they sweep east across central Illinois through the remainder of the afternoon and evening. Shear/instability parameter space is favorable to support organized severe thunderstorms with the primary hazard being damaging straight line winds. Given the strong 0-3km shear values of 40-50kt along the front, do also anticipate mesovortices to form supporting a QLCS tornado threat. The confidence in severe storms is higher south of I-72 and especially along and south of the I-70 corridor where SPC introduced a moderate risk earlier today. Have lower confidence to the north of I-72 given the aforementioned concerns in recovery. Some of the latest CAMs including the 18Z HRRR have trended the strongest convection further south. Placement details should become more clear Wednesday morning. By early to mid evening, the leading line of storms is expected to begin pushing into Indiana with precip and severe chances diminishing in its wake. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 259 PM CDT Tue Apr 12 2022 By Thursday morning, the cold front will be pushing across the Upper Ohio River Valley while the occluded surface low continues to slowly meander northward across the Great Lakes region. High pressure building across the lower to mid Mississippi Valley will contribute to a strong pressure gradient across central Illinois resulting in breezy west to southwest winds through the day. Meanwhile, deep mixing will help to tap into stronger flow aloft. Surface gusts in excess of 30 kt are a decent possibility and will need to monitor the potential for occasional gusts near 40 kt which would reach wind advisory criteria. Colder air wrapping around the low will overspread the area through the day and temperatures and afternoon highs will be a solid 10 to nearly 20 degrees cooler compared to prefrontal conditions. Winds remain breezy to start the day Friday, but not quite as strong as Thursday and should gradually diminish with approaching col area moving overhead Friday afternoon. Will have to monitor for low precip chances as WAA aloft helps to saturate the mid levels. Forcing is somewhat limited Friday with H5 height rises still showing slightly positive tendencies, but upper level divergence in the LER of the jet and WAA will support at least a chance of rain Friday. An expansive surface high will overspread the region to start the weekend resulting in fair weather Saturday, albeit still below normal with northwest flow aloft. A compact wave emanating from the Pacific NW will dig across the Midwest late Sunday into Monday bringing the next chance for rain to central Illinois. A reinforcing shot of cold air behind this system will bring temps back to near the freezing mark Monday night and Tuesday night. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 639 PM CDT Tue Apr 12 2022 Complex aviation forecast over the next 24 hours...with the primary concern being timing of convection at the central Illinois terminals on Wednesday. Line of storms will develop along a dryline across Nebraska/Kansas this evening...then will spill into the Illinois River Valley in a much decayed state toward dawn. Have only included VCSH at the TAF sites during the morning hours accordingly. The main round of convection will develop/spread northeastward into the region toward midday...then will push east of the terminals by early Wednesday evening. Still quite a bit of uncertainty about timing/duration of thunder, with KPIA perhaps being missed entirely. Have therefore only mentioned VCTS, with thunder mention ending along/west of I-55 by late afternoon as the emphasis shifts further east and south. Winds will be very strong/gusty...with southerly gusts of 25-35kt tonight. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Barnes SYNOPSIS...Barnes SHORT TERM...Deubelbeiss LONG TERM...Deubelbeiss AVIATION...Barnes
Area Forecast Discussion
National Weather Service Indianapolis IN
1142 PM EDT Tue Apr 12 2022 ...Updated Aviation Discussion... .Forecast Update... Issued at 948 PM EDT Tue Apr 12 2022 Radar trends and HRRR suggest convection associated with upstream waves over the South will not make it in to southwestern parts of central Indiana until after 4 AM. So, slowed down the PoPs though 12z Wednesday. Breezy south winds with gusts to 30 mph along with increasing convective debris canopy will result in near stationary temperatures in the 60s through the overnight. Although instability will be weak per instability progs and BUFKIT, there will still be enough for thunder. && .Short Term...(This evening through Wednesday night) Issued at 254 PM EDT Tue Apr 12 2022 ...SEVERE THUNDERSTORM THREAT WEDNESDAY INTO WEDNESDAY NIGHT... BOTTOM LINE UP FRONT *A line of strong to severe thunderstorms will move across Indiana Wednesday evening *Damaging winds and a few tornadoes are the primary threats, along with heavy rain *Uncertainty remains with timing and extent of severe potential Through Tonight A cold front dropped southward across the region last night, and stalled out just south of our CWA. The stalled front is now lifting northward as a warm front due to a large trough ejecting out of the Rocky Mountains. In response, clouds have been increasing from south to north today. Cloud cover will continue to progress northward as the day goes on with a few showers possible. While there is some weak isentropic lift associated with the advancing front, overall forcing is limited and thus not expecting widespread shower activity this afternoon. An upper-level shortwave trough currently over Texas will get absorbed in the flow ahead of the ejecting trough and lift northeastward towards Indiana. This feature is not expected to phase with the trough, however. Instead, it will remain a separate feature and ride northward just ahead of the main trough. As it moves north tonight, showers and thunderstorms are likely after 12Z. Wednesday and Wednesday Night Convection should be ongoing by Wednesday morning as the lead shortwave moves through and exits to the northeast. By midday, the main trough should begin to take on a negative tilt and move into our area. Divergent flow aloft will promote lift along and ahead of an advancing cold front. Hi-res models currently depict intense convection developing along the front, reaching Indiana late in the afternoon or in the early evening. Current timing appears to be clustered around 00Z. Mean flow oriented parallel to the front imply a linear convective mode is preferred. Sufficiently curved hodographs would imply a few embedded circulations within the line could develop. So in addition to damaging wind gusts, a few tornadoes are also possible as these storms move across the area. Warm air advection ahead of the main line of storms could destabilize the environment enough that a few discrete cells are possible ahead of the line. Deep layer shear over 50 kts and sufficient helicity could lead to any discrete cells posing a hail and tornado hazard. One caveat to the severe threat is the morning convection. Widespread early morning rainfall may stabilize the environment enough to reduce the extent of the discrete cell severe threat later in the day. However, if the early rain is on the lesser end of the range of possibilities, the atmosphere may become more destabilized and the potential for discrete convection may end up being higher. Regardless, strong dynamics and forcing will be enough for the linear severe potential to remain despite variations in potential environmental stability. In addition to the severe potential, the aforementioned strong low- level flow could lead to general wind gusts over 30 to 35 kt wind gusts across the region tonight into tomorrow. The gusty winds, along with the severe weather threat, will diminish once the cold front has passed. Cooler air will filter into the region with lows as low as the upper 30s by early Thursday morning. && .Long Term...(Thursday through Tuesday) Issued at 254 PM EDT Tue Apr 12 2022 A milder period can be expected in the long term period, with flow becoming quasizonal or weakly cyclonic late in the week into the weekend as the larger closed low pressure system lifts northeast out of the region and fast upper level flow promotes a more progressive pattern. Cooler temperatures, near to slightly below normal, will move in Thursday in the wake of an exiting cold front and then persist through the period. An elongated jet aloft will continue gusty winds into the day Thursday as well, with gusts up to around 40 MPH mainly for areas to the NW. At the surface, high pressure will be passing through the area Thursday as well, so expect mostly clear skies with the gusty winds. Weak upper level waves may promote low chances for showers Friday into Friday night, with slightly more substantial shower chances needed late in the weekend into early next week as a somewhat more amplified upper level trough moves along the northern periphery of the country into the Great Lakes. For early next week, models are suggesting at another upper system that will bring better chances for rain, but given the variety in solutions, it is too soon to nail down any details. && .Aviation...(06Z TAF Issuance) Issued at 1141 PM EDT Tue Apr 12 2022 IMPACTS: -Mostly VFR flying conditions overnight, but brief MVFR ceilings developing in convection after 10z or so. -Thunderstorms possible after 10z. Strongest storms after 21z. -Winds 160-200 degrees 15 to 20 knots with gusts to 30 knots through 03z Thursday. Then, winds switching to around 270 degrees behind the cold front. -Non-convective low level wind shear through 11z. DISCUSSION: A strong storm system will lift northeast into the northern Plains today. Meanwhile, associated cold front will sweep through the terminals late tonight. The front, combined with strong wind shear, instability and deep moisture will bring widespread showers and thunderstorms to the terminals through tonight. The strongest storms will move through this evening. Mostly VFR flying conditions will deteriorate to MVFR at times after the showers arrive this morning. Low level wind shear will be a threat with the low level jet overhead. Breezy or windy conditions are expected through the TAF period. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ Update...MK Short Term...Eckhoff Long Term...KH Aviation...MK
Area Forecast Discussion
National Weather Service Jacksonville FL
910 PM EDT Tue Apr 12 2022 .UPDATE... Mostly clear over the area this evening with sfc high pressure well to our east. Prevailing south to southeast low level flow shown in the obs and latest VWP and JAX sounding. Sea breeze induced flow is fairly strong for coastal areas with winds up to 15 mph and gusty but will settle down overnight. Noted JAX sounding and JAX VWP showed around 20 kt at 1000 ft this evening. Otherwise, expect to see more high clouds streaming in from the west per latest satellite trends and HRRR guidance. We continued to keep the lows a bit above the min temp guidance but still tweaked them a bit lower based on latest performance of the MOS and NBM forecasts. Some patchy fog is possible and mainly toward interior areas of southeast GA early Wednesday morning. Otherwise, no significant changes in the forecast at this time. .MARINE... Winds and seas are on track in the latest CWF with only minor adjustments needed in forecast grids. Main change was with the winds initially tonight near 15 kt but consensus shows winds will settle more southerly at 10-15 kt toward sunrise. && .PREV DISCUSSION [748 PM EDT]... .NEAR TERM [Through Tonight]... High pressure will remain in command of the sensible weather tonight. Aside from flat cumulus developing along the Atlantic sea breeze and across inland SE GA and the Suwannee Valley, mostly clear skies will prevail this afternoon. Breezy conditions will continue along the coast through the rest of the afternoon with gusts up to 25 mph before diminishing this evening. Dirty upper ridge will introduce bouts of cirrus into the area this evening. There should be enough boundary-layer wind and high clouds in place to prevent widespread, organized fog tonight but patchy fog development will be possible in wind-sheltered areas. Lows tonight will be warmer tonight especially at the coast where lows will be in the mid/upper 60s while inland areas will read in the low 60s. .SHORT TERM [Wednesday Through Thursday Night]... Warm, moist southerly flow continues Wednesday with surface high pressure well east in the open Atlantic. Meanwhile aloft, strengthening southwesterly flow will develop ahead of an upstream impulse. An influx of high clouds will precede the upper impulse Wednesday and continue to drift overhead Thursday ahead of an advancing cold front from the northwest. The cold front will slow and weaken as it pushes into SE GA Thursday afternoon. Despite weakening, sufficient convergence along the boundary will support scattered showers and isolated storms across SE GA during the afternoon hours. Further south in NE FL shower chances will be lower due to stubborn low stratus and drier, warmer air in the low-levels. Strong warm advection will boost temperatures well into the 80s by Thursday with muggy overnight lows in the mid/upper 60s both nights. .LONG TERM [Friday Through Tuesday]... A weakening cold front will slow, become diffuse, and eventually stall somewhere across SE GA. Low level moistening will push PWAT toward 1.5" with model soundings indicating afternoon instability in the range of 1200-2000 J/Kg CAPE. Synoptic shear production looks meager at this time but mesoscale/sea breeze influence may lead to locally elongated hodographs and focused convergence during Friday afternoon. Expect stronger storms to favor these enhanced areas of convergence, with scattered run-of-the-mill thunderstorms elsewhere; strong storms will be capable of gusty winds and hail. Frontal zone will lift slightly northward Saturday before another decaying, upstream cold front overtakes and presses into the area Sunday and stalls once again. These features will continue unsettled weather through the weekend and into early next week. Late in the period, ensemble systems generally agree on a sweeping frontal passage will occur Tuesday with cool, northwest flow in its wake. Above normal temperatures are expected through the weekend and into next ahead of the stronger cold front. .AVIATION... [Through 00Z Thursday] Prevailing VFR expected through the forecast period with mainly SCT- BKN cirrus and some FEW-SCT cumulus at times. Some low chance for patchy fog late tonight mainly inland TAFs between 06Z-12Z Wednesday, but at this time no significant restrictions are indicated in the forecast based on latest model guidance and soundings. Sfc winds from the southeast continue a bit breezy this evening roughly 8-14 kt and gusty. These winds will settle lower toward and after midnight. Southerly winds initially Wednesday morning will trend toward the southeast during the aftn again around 8-14 kt with some gusts near 20 kt. .MARINE... High pressure will remain well to the east through the end of the week. Meanwhile, a cold front will approach from the northwest on Thursday and stall across the waters on Friday before wobbling slightly north of the waters this weekend. The frontal zone will support scattered showers and thunderstorms. Southerly flow will increase to SCEC levels by Wednesday night through Thursday as gradients tighten ahead of the front then relax Friday and through the weekend in the vicinity of the stalled boundary. Rip Currents: Influence of sea breeze and shore-parallel currents will lead to Low to Moderate Rip Current risk at area beaches through Thursday. .FIRE WEATHER... Increasing moisture and persistent southerly surface and transport winds expected through Thursday. On Wednesday, increasing southerly transport will lead to locally high daytime dispersion across the Okefenokee NWR, Ocala NF, and other inland forests along I-75. A weak cold front will enter and stall over the area Friday with scattered showers and thunderstorms along it. Unsettled weather will continue through the weekend and into early next week with the passage of couple more frontal systems. Patchy fog is expected tonight along and east of I-95. .HYDROLOGY... The Altamaha River continues to rise with portions entering minor flood stage this evening. Santa Fe River continues to recede however portions of the river will remain in flood. Unsettled weather will bring more precipitation to the area this Thursday and through the weekend. Upcoming precipitation is not expected to exacerbate ongoing flooding or result in new river flooding. && .PRELIMINARY POINT TEMPS/POPS... AMG 60 84 63 83 63 / 0 0 20 50 30 SSI 65 79 67 81 66 / 0 0 10 20 30 JAX 60 84 67 86 66 / 0 0 10 30 20 SGJ 65 82 68 84 68 / 0 0 10 30 20 GNV 59 84 65 86 65 / 0 0 10 20 10 OCF 59 85 65 86 66 / 0 0 10 30 10 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. &&
Area Forecast Discussion
National Weather Service Lake Charles LA
955 PM CDT Tue Apr 12 2022 .DISCUSSION... Local 88Ds are a little quieter than earlier in the evening with the afternoon convection driven by the initial disturbance aloft now mostly east of the forecast area. Spotty convection continues to pop up in this activity`s wake over the forecast area as mesoanalysis shows we remain very moist and fairly unstable. Main feature for tonight looks to be the well organized MCS beginning to move into nwrn LA from nern TX...the tail end of this feature looks to miss our nwrn zones on its current trajectory. However additional convective development is ongoing off its srn flank and considering our local airmass continues to show good instability and lapse rates with excellent helicity, will have to keep an eye on this activity should it get into our area closer to midnight. POPs/wx grids were updated per latest trends. Elsewhere, inherited grids/zones look in good shape as is. Update out shortly. 25 && .PREV DISCUSSION... /issued 640 PM CDT Tue Apr 12 2022/ DISCUSSION... For the 04/13/2022 0000 UTC TAF package. AVIATION... Sctd storms on radar late this aftn will continue to move northeast through the evening, with chcs tapering off overnight. The passage of the convection has left some breaks in the low clouds, resulting in what is expected to be a brief period of VFR conditions early this evening. Given copious low level moisture, expect MVFR cigs filling back in acrs the area by 03-06Z. MVFR cigs are expected to persist through day at BPT/LCH/AEX with a possible improvement to VFR at the Acadiana terminals during the morning. Another round of SHRA/TSRA will move in from the west during the aftn ahead of a cool front. S-SE winds will remain elevated and gusty through the period. Gusts to near 30 KT can again be expected during the day Wednesday. 24 PREV DISCUSSION... /issued 435 PM CDT Tue Apr 12 2022/ SHORT TERM [Today through Wednesday]... Showers and thunderstorms are currently progressing across the area with gusty winds present. Showers and thunderstorms will be possible into the overnight hours. Some storms could be severe. A frontal system will be expected to move through the area tomorrow. Showers and thunderstorms will be expected tomorrow from the morning into the afternoon and overnight hours. The HRRR is indicating sufficient CAPE and shear for the possibility of severe thunderstorms. Damaging wind gusts, large hail, lighting, and a few tornadoes will be possible. PWATs are showing in the 1.7 to 1.8 inch range which indicates the possibility of flooding. HRRR soundings also show significant moisture from the low-levels to the upper-levels. A significant cooldown will not be expected post-frontal with drier weather expected on Thursday. 55 LONG TERM [Friday through Monday]... After an initially cool start Friday morning, an elongated surface ridge will push towards the east coast during the day turning winds back out of the south and lifting a warm front out of the gulf. Dewpoints behind the boundary will climb into the mid to upper 60s with the warm front providing a weak focus for scattered showers and thunderstorms. Steady southerly flow will prevail in the wake of the warm front through the weekend which will will maintain afternoon highs near or slightly above normal. A surface low will develop over northern Texas Friday and drift slowly southeast through the weekend providing a weak focus for isolated to scattered daily afternoon showers and thunderstorms. Weak perturbations in the otherwise zonal flow aloft may periodically aid in this development. A shortwave moving into the Pacific northwest Saturday will swing rather quickly across the western and central U.S. pushing another robust cold front through the region Monday dropping temperatures below seasonal norms through the first half of next week. Jones MARINE... Elevated onshore flow will continue into tomorrow. Showers and thunderstorms will be possible for the remainder of today through Wednesday night. Some of the storms could be severe. A Small Craft Advisory is currently present through tomorrow. 55 LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...Small Craft Advisory until 7 PM CDT Wednesday for GMZ430-432-435- 450-452-455-470-472-475. && .PRELIMINARY POINT TEMPS/POPS... AEX 68 81 53 77 / 80 90 50 10 LCH 68 79 58 80 / 70 90 50 10 LFT 69 81 60 81 / 70 90 80 10 BPT 69 81 59 80 / 40 70 20 0 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...Small Craft Advisory until 7 PM CDT Wednesday for GMZ430-432-435- 450-452-455-470-472-475. && $$
Area Forecast Discussion
National Weather Service Louisville KY
900 PM EDT Tue Apr 12 2022 .Forecast Update... Issued at 858 PM EDT Tue Apr 12 2022 Things have been relatively quiet so far this evening across central Kentucky and southern Indiana, with more clouds across the Kentucky Bluegrass and more sun across south central Kentucky. Where there has been more sun this afternoon, a few instability-driven showers and thunderstorms have developed over the past few hours, particularly along the KY/TN border where MLCAPE values of 1000-1500 J/kg are present. Expect these showers to diminish in intensity and coverage over the coming hours as the atmosphere stabilizes after sunset. Otherwise no major changes to the forecast at this time. Expect cloud cover to gradually build from south to north across the region tonight as another surge of low-to-mid level moisture overspreads the area. After a late evening lull, PoPs will begin to increase again from southwest to northeast after 13/07Z. A peculiar manifestation in the high-res guidance is a suggestion by the 12/23Z HRRR that a remnant MCV left over from ongoing convection across Texas could make its way into central Kentucky by late tomorrow morning, potentially impacting the morning wave of precipitation. For now, this is nothing more than a mere peculiarity until it is consistently depicted in models/observed. && .Short Term...(This evening through Wednesday) Issued at 300 PM EDT Tue Apr 12 2022 ...Strong to Severe Storms Possible Wednesday Evening and Overnight... **************************************************** *** Main Headlines for Wednesday/Wednesday Night *** **************************************************** - Rain and embedded non-severe storms through early Wednesday afternoon. - Gusty southerly winds during daytime (30-40 mph) - Multiple rounds of severe weather possible Wednesday evening through the overnight hours - Severity/timing of storms continues to remain uncertain A warm front is slowly lifting northward through the region this afternoon per latest observational guidance. Clouds and showers lingered for much of the morning hours near the vicinity of the front, but with it lifting out of the region, we are now starting to see breaks in the clouds and precipitation. This drying trend should continue into the evening and overnight hours. The next round of rainfall looks to arrive early tomorrow morning as a shortwave embedded within the main trough axis swings into our region. Best chances for precipitation look to be west of the I-65 corridor. This round of precipitation should be non severe as instability looks to be meager with poor low/mid level lapse rates and marginal low level dewpoints. This rainfall should be pushing north of the I-64 corridor by ~20z. Winds will also be breezy out of the south in the wake of this rain, with gusts in the 30-40 mph range. After 20z, attention then turns to the west where a line of strong to severe storms along a cold front will be ongoing and quickly racing toward our region. Several high-res CAMs also show a weak vort lobe ahead of the front and develop a second line of convection within the warm sector. We could see storms arriving in our western CWA as early as 21z, but the main front/line will not likely arrive until after 00z. Confidence with respect to the severity of storms remains low, as the timing between multiple lines/waves of showers and storms will impact the overall thermodynamic environment (i.e., will we be able to destabilize enough in between rounds of showers/storms to get strong to severe convection?). Generally thinking that storms west of the I-65 corridor have the best chance for severe potential, where the greatest instability corridor will reside. East of I-65, instability becomes quite meager, and models tend to weaken convection in this area due to limited or near-zero instability. Should severe storms form, the main threats would be damaging straight line wind gusts and isolated embedded tornadoes within the line. A localized flash flood threat will also be possible where training of storms occurs. The severe threat should end in our east by about ~09z. .Long Term...(Wednesday night through Tuesday) Issued at 255 PM EDT Tue Apr 12 2022 Long term period features much cooler and drier conditions for our region. By Thursday morning, the well-advertised cold front will be departing off to our east, taking with it the precip chances and above normal temps. Quick moving sfc high will be arriving, helping to clear out skycover. While Thursday should feature cool post- frontal NW flow and a drier airmass, heavy rain from the recent passing cold front may result in some minor river flooding issues. OHRFC currently forecasts minor flooding at some stage points along the Green River by later this week, and possibly at Rough Rover too. Otherwise, not expecting much river flooding issues further east. Expect temps to be a touch cooler than normal, mainly in the low to mid 60s. Warmest day of the long term comes Friday, with temps in the upper 60s and near 70F as the upper level pattern flattens some and the aforementioned sfc high over the Carolinas filters some warm return flow into the Ohio Valley. A weak low-level disturbance will bring a moisture-starved frontal boundary through the region Friday night, though some isolated to scattered light showers will be possible. Perhaps enough dry air below 700mb could be enough to evaporate most precip before hitting the ground, so decided to slightly lower PoPs for Friday night to keep our chances in the Slight Chance category. This front will sag south of the region and stall across the Deep South by Saturday. A stronger sfc high from Canada will begin to build into the region on Saturday, resulting in cooler NNW flow. The region may be split on Sat between drier conditions to our north from the sfc high, and slight PoPs to our south caused by the stalled boundary just to our south. Not expecting much in the way of impacts through the weekend. Temps will slightly get cooler each day through the weekend and into early next week. CPC highlights the 6-10 day outlook with likely probabilities of below normal temps. Greatest rain chances of the period come at the start of early next week as we get another disturbance moving through the area, but it`s too soon to get into the finer details at this time. && .Aviation...(00Z TAF Issuance) Issued at 751 PM EDT Tue Apr 12 2022 The airports will be well within the warm sector of a powerful spring storm system over the Plains tonight. An area of showers, with a few embedded rumbles of thunder, over the lower Mississippi Valley this evening will cruise northeastward into the region tonight into Wednesday morning, though flying conditions should prevail VFR outside of locally heavier downpours. Of possibly greater concern will be brisk surface winds around 10-15kt and marginal speed LLWS as a low level jet intensifies from the western Gulf to the Great Lakes. Tomorrow a sharp cold front will approach from the west with gusty south winds out ahead of it. Morning showers will become more widely scattered in the afternoon. We could see some convective redevelopment by late afternoon, but the main show will be a potential band of very strong storms moving in from the west Wednesday evening. Will put some TSRA in the extended planning part of the SDF TAF, with future TAF issuances employing greater detail and probably some timing adjustments. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...None. KY...None. && $$ Update...CSG Short Term...DM Long Term...CJP Aviation...13
Area Forecast Discussion
National Weather Service Mobile AL
1052 PM CDT Tue Apr 12 2022 .NEAR TERM /Now Through Thursday/...Southwest flow aloft this evening transitions to westerly difluent flow aloft by Wednesday evening into Thursday. This is owing to a powerful upper level trough over the central Plains quickly taking on a negative tilt during the day Wednesday into the ArkLaTex region and a subtropical jet nosing into the northern Gulf of Mexico. As this occurs, a low pressure system occludes across the north-central midwestern states as a trailing surface cold front races east across the gulf coast states Wednesday night into Thursday morning. This feature should transit most of the CWA by Thursday morning, gradually becoming more diffuse and slowing as it does so. For the rest of tonight, we continue to have light to moderate showers attempting to move into our southeastern MS counties. So far they have struggled to make much progress and for the most part a majority of the CWA should remain dry tonight outside of our interior MS and southwest AL counties. A feature of interest that recent HRRR runs has been honing in on is an ongoing mature MCS across western/northwestern Louisiana possibly knocking on our southeastern MS counties and interior southwestern AL counties by daybreak. Shear and instability should be sufficient through the night to support a continuation of this feature with around 500 to 1,000j/kg of CAPE and 30 to 35kts of effective shear across the area through the overnight hours. It`s a bit early to know exactly how this will evolve as most 00z CAMs (even the 00z HRRR) were not as keen on this. With that said, the 00z CAMs have not had a good handle on the ongoing convection while recent HRRR runs depicts this better. Given that, I felt it worth mentioning for now. Future CAMs runs will need to be monitored to gain a meaningful understanding of how this MCS will evolve before making any forecast changes at this time. Otherwise, expect isolated to scattered showers over southeastern MS and interior southwestern AL through the overnight hours. If that wasn`t enough to talk about, there is some evidence of a wake low beginning to develop across south-central Louisiana as precipitation continues to evaporate across the area. Surface observations over that area support this development with several ASOS stations reporting winds gusting from the east/east- southeast at 30 to 50mph. Latest CAMs even note this feature transiting east into southeastern MS and southwestern AL within the next 3 to 6 hours. Confidence on how this evolves and if it truly makes it into the CWA is low, and thus will hold off on any forecast changes at this time. If confidence becomes high enough this will pass over our area then changes to the current wind forecast would be needed and the possibility of a short fused wind advisory for portions of the area. Lows should dip into the lower to middle 60`s. Wednesday should start off mostly dry barring the aforementioned MCS doesn`t throw a wrench into the forecast. Ample moisture return continues with strong daytime heating bringing temperatures into the lower 80`s for most locations by the afternoon hours. With forcing remaining well to the west of the area through Wednesday afternoon, not anticipating much if any shower or thunderstorm activity for most of the day. It`s once we get to the evening and overnight hours Wednesday night into Thursday morning that the weather becomes more interesting. As the aforementioned upper level difluence overspreads the region, scattered showers and thunderstorms should develop over the area from west to east, beginning in the early evening hours. Models hint at two possible rounds of storms, with the first belonging to initial convection firing over southeastern MS into southwestern AL Wednesday evening over the open warm sector. This convection will develop in around 1,000 to 1,500 j/kg SBCAPE and 30kts of shear. Expect this to mainly be multicellular and pose a threat for large hail and damaging wind gusts. Can`t rule out a tornado or two if favorable storm mergers can result in a mesoscale accident. Confidence in this first round remains low to moderate. The more confident round will be associated with the front itself. CAPE values remain near 1,000j/kg during the overnight hours and shear increases modestly to near 35 to 40kts. Overall anticipating a squall line to transit the area from northwest to southeast during the overnight hours into Thursday morning, with a primary threat of damaging wind gusts. Once again can`t rule out a tornado or two with the line itself. In addition to the severe weather threat, localized flash flooding of low lying areas is possible. This is particularly the case if the line slows to a crawl and becomes oriented west to east allowing for training of thunderstorms over the same areas by Thursday morning into early afternoon. Confidence in this remains relatively low to moderate. A High Risk of Rip Currents remains in effect through late Friday night. MM/25 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...High Rip Current Risk through late Friday night for ALZ265-266. FL...High Rip Current Risk through late Friday night for FLZ202-204- 206. MS...None. GM...Small Craft Advisory until 4 PM CDT Wednesday for GMZ630>632-650- 655-670-675. && $$ This product is also available on the web at:
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
546 PM CDT Tue Apr 12 2022 .UPDATED for 06Z aviation discussion... Issued at 536 PM CDT Tue Apr 12 2022 && .DISCUSSION...(This evening through Tuesday) Issued at 230 PM CDT Tue Apr 12 2022 * KEY MESSAGES: (optional) - Severe thunderstorms are possible through this evening from southwest and south central Minnesota through east central Minnesota and into west central Wisconsin. Although isolated severe weather is possible prior to 7 PM, most of the potential for severe storms will be from 7 PM onward. - Strong winds are expected Thursday into Thursday night, with gusts of 40 to 50 mph possible, especially along and south of the Minnesota River valley. Visible satellite imagery this afternoon shows clouds locked in across the area, with the nearest clearing from southeast South Dakota into western Iowa. Surface low of around 985 mb was analyzed over eastern Nebraska. This low will lift northeast through this evening, and should bring the warm frontal boundary into far southern and southeast Minnesota after 00Z. Instability will be somewhat limited, and will be primarily elevated, although the south/southeast portion of the area could see some storms rooted in the boundary layer which would enhance tornado potential there. In addition, the eventual evolution into more of a QLCS structure east of I-35 after 02Z could favor the development of low-level mesovortices and short- tracked tornadoes and/or enhanced areas of wind damage. Otherwise, hail looks to be the primary concern over most of the area, including the Twin Cities metro, where forecast soundings from the RAP and HRRR favor things remaining elevated. Even with somewhat limited instability, low-level and deep layer/effective shear will remain high through the evening, favoring rotating updrafts in discrete elevated storms, further enhancing the large hail potential. The forecast 0-3 km bulk shear fields across the southern portion of the area this evening favor greater than 30 kt of shear with any potential storm/line motion, which is why mesovortices (as mentioned above) would be favored if/when a QLCS structure evolves. Meaningful convection should push east of the area by around 05-06Z, with some lingering showers possible, mainly over the north. The surface low will occlude from Minnesota into Wisconsin on Wednesday, with the bulk of the lingering precipitation staying north/east of the forecast area, although some PoPs are still warranted (particularly north of I-94). Cold advection increases Wednesday night into Thursday, along with the pressure gradient. Winds look to significantly increase Thursday into Thursday night, with gusts to 50 mph a possibility (especially from west central into south central Minnesota). Included gusts above 40 mph for much of the area Thursday afternoon/evening, and subsequent forecasts should be able to refine things, with the definite possibility of a wind advisory being needed at some point. Medium range guidance is in good agreement after Thursday, with unseasonably cool temperatures continuing through the weekend, although precipitation chances are limited and light through that time. Return flow will precede the next system of note Sunday afternoon/evening, with sufficient moisture and lift for rain/snow across the area. It looks to cool off a bit behind this system, with any significant warming holding off until after the current seven day forecast period. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 536 PM CDT Tue Apr 12 2022 Areas of MVFR/IFR developing this evening as thunderstorms lift up from Iowa and move across Minnesota and Wisconsin. These storms could be severe with strong winds and large hail. Expect a strong wind shift as well with a surface low moving through. Winds will start out easterly this evening, and then take on a more westerly direction with strong gusts near 30kts on Wednesday after the surface low passes through. KMSP... No significant changes from the previous forecast. Thunderstorms are expected later this evening with MVFR/IFR clouds developing as well. These storms could produce strong winds or large hail. Winds will be easterly, and then switch northeast and to the north tonight, eventually becoming westerly on Wednesday. Clouds should lift towards VFR by the late afternoon and evening. /OUTLOOK FOR KMSP/ Thu...IFR/MVFR chc -RASN. Wind W 20-25 kts, gusts 40-45 kts. Fri...VFR. Wind W 20-25 kts, gusts 35-40 kts. Sat...VFR. Wind WNW 10-15 kts, gusts 25kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...WFO MPX AVIATION...JRB
Area Forecast Discussion
National Weather Service Norman OK
1101 PM CDT Tue Apr 12 2022 ...New AVIATION... .SHORT TERM... (This evening through Wednesday) Issued at 331 PM CDT Tue Apr 12 2022 * Storms? - Severe This Afternoon/Evening * Fire Weather * Strong Winds Discussion: No significant changes to expectations in the big picture with wildfire potential west and a conditional potential of severe storms east. The shortwave over north Texas will likely be the main synoptic-scale forcing mechanism and with that, the highest potential for storm development late this afternoon and this evening will be in the southeast. So the big question remains, will there be storm development on the dryline? Some of the models suggest the cap weakening and very little negative area on the soundings, especially across southwest and south central Oklahoma this afternoon. But without significant forcing near the dryline, that is no guarantee of storm development on the dryline. And we may be fighting some subsidence north of the north Texas shortwave. Some of the convective-allowing models (including the HRRR and the 12Z HiRes-ARW and 3 km NAM) are showing some potential of development in the SW or south central. Farther north, there is still more uncertainty on potential development along the dryline. But if any storms do develop, the atmosphere is quite unstable with sufficient shear for supercells. Regardless, without significant forcing on the dryline, we do not expect widespread storms. We will continue to monitor mesoanalysis and satellite trends through the day to assess the potential for development. In the west, the winds continue to increase across the western and central Oklahoma and Texas panhandles, and we expect to see winds increase in northwest Oklahoma this afternoon. The dryline was slow to mix eastward today, but is in parts of western Oklahoma and western north Texas where relative humidity is 20 percent or lower. Expect fire weather conditions to worsen through the afternoon in the west as the dryline mixes east and very dry air spreads into the area along with the increasing winds. This remains a potentially dangerous wildfire situation in the west, especially in northwest Oklahoma. Models show a cold front moving across the area tonight into Wednesday with winds shifting to the NW/N. This could cause problems to any ongoing fires. Models also show some showers/storms developing near the front late tonight into Wednesday morning affecting eastern portions of the fa, mainly along and east of I-35. Despite cooler temperatures (highs 60s and 70s) Wednesday, gusty winds, low RH, and dry fuels will lead to near critical/critical fire weather conditions across western portions of the area. Will continue with the current Fire Wx Watch. && .LONG TERM... (Wednesday night through next Monday) Issued at 331 PM CDT Tue Apr 12 2022 Focus was on the next couple of days. Colder temperatures are expected Wednesday night/Thursday morning. Freezing temperatures could be possible in parts of northern OK. Shower and thunderstorm chances will return to portions of the area Friday into the weekend, generally along and east of I-35. && .AVIATION... (06Z TAFS) Issued at 1056 PM CDT Tue Apr 12 2022 LLWS and temporary MVFR cigs will be the main forecast concerns overnight. A line of thunderstorms has developed along the cold front across far northern OK late tonight and this will be watched for any amendments later for TSRA near PNC. Otherwise, some light rainfall and brief low cigs may accompany the front into the early morning hours Wed. A gusty wind shift from the north will also occur. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 84 52 67 39 / 20 20 10 0 Hobart OK 92 50 70 36 / 0 0 0 0 Wichita Falls TX 90 58 76 40 / 10 10 0 0 Gage OK 92 41 61 32 / 0 10 10 0 Ponca City OK 85 48 60 33 / 10 30 10 0 Durant OK 81 63 79 42 / 30 30 20 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...Fire Weather Watch from Wednesday afternoon through Wednesday evening for OKZ004>006-009>011-014>017-021>023-033>038-044. TX...Fire Weather Watch from Wednesday afternoon through Wednesday evening for TXZ083>090. && $$ SHORT TERM...26 LONG TERM....25 AVIATION...03
Area Forecast Discussion
National Weather Service Pueblo CO
958 PM MDT Tue Apr 12 2022 .UPDATE... Issued at 957 PM MDT Tue Apr 12 2022 Based on 00z model runs, have cancelled Winter Storm Warnings and Advisories for the southwest mountains for the remainder of tonight as any additional accumulations will be spotty and light. Have maintained Warnings and Advisories for the central mountains where northwesterly flow will provide favorable orographics for at least some moderate snow and blowing snow into Wednesday morning across the higher peaks and passes. -KT UPDATE Issued at 815 PM MDT Tue Apr 12 2022 High winds have come down and humidity values have crept up above critical thresholds both ahead and behind a cold front advancing through the southeast plains. Winds will remain gusty across the region through midnight but with damaging gusts and critical fire weather conditions no longer expected, have allowed the High Wind Warning and Red Flag Warning expire. -KT && .SHORT TERM...(Tonight) Issued at 344 PM MDT Tue Apr 12 2022 Key Messages: 1) High winds with blowing dust continue this afternoon, mainly along and south of Highway 50. The High Wind Warning for Teller, El Paso, and lower Chaffee counties has been cancelled. 2) Fire weather concerns also continue this afternoon, with high winds and low RH values still supporting high fire danger across much of southern Colorado. 3) Light to moderate snow continues across the Continental Divide this evening/tonight. The downward trend with the winds/gusts noted over the last couple of hours will continue for the remainder of the afternoon. Latest RAP analysis still indicating some stronger flow aloft translating overhead though, which is still supporting some wind gusts to around 60 mph mainly along and south of Highway 50. So, have continued the High Wind Warning for these areas but did cancel it for Teller, El Paso, and lower Chaffee counties where these higher gusts are no longer expected. Have not received any reports of blowing dust here recently, however, can see some patches of blowing dust on latest satellite imagery. Additionally, the winds and gusts expected for the remainder of the afternoon will continue to support blowing dust, and so have continued the Blowing Dust Advisory this afternoon. As noted earlier, the precip development and cloud cover along with some cooler temps have kept RH values higher in spots mainly along and west of I-25. Elsewhere, RH values are still down to around 10 percent. Despite the higher RH values in spots, did keep the Red Flag Warning in effect for much of southern Colorado this afternoon, as the very strong to damaging winds in place are very concerning. Lastly, snow development has diminished for much of the day across the Continental Divide, though still snowing across the southwest mountains. With the snow still occurring across the southwest mountains and snow anticipated to return to the central mountains this evening, have kept the winter headlines in place. .LONG TERM...(Wednesday through Tuesday) Issued at 344 PM MDT Tue Apr 12 2022 Key messages: 1) Breezy to Windy Conditions with Critical Fire Weather conditions expected across portions of south central and southeast Colorado again Wednesday and Thursday. Latest models continue to indicate moderate to strong northwest flow aloft across the region on Wednesday, as a secondary trough translates across the central Rockies tomorrow morning and into the central High Plains into the afternoon. Increasing northwest orographic flow will bring another round of snow across the central mts, with another 1 to 3 inches possible across the higher terrain, greatest north of Cotton Wood Pass through the day tomorrow. While can`t totally rule out a few showers spreading out across the eastern mountains and plains early tomorrow morning, latest models remain consistent with very dry air mixing into south central and southeast Colorado behind this passing trough later Wednesday morning and into the afternoon with dew pts tanking into the single digits above and below zero areawide by tomorrow afternoon. Although temperatures cool behind the passing system, with highs only in the 40s to lower 50s expected across the lower elevations, and mainly in the 20s and 30s over the higher terrain, min rhs are still expected to drop into the 10 to 15 percent range across the San Luis Valley and most of the southeast plains. This combined with breezy westerly winds of 20 to 40 mph developing from west to east through the late morning and afternoon will once again lead to critical fire weather conditions being met across the region, and have upgraded the previous fire weather watch from noon to 7 pm Wednesday for the southeast plains to a Red Flag Warning, and also added the San Luis Valley as well as northern El Paso County to the warning. Breezy to windy westerly flow remains progged across the region Thursday before slowly diminishing through the day on Friday, as short wave ridging builds across the Rockies. This will bring warmer and drier conditions to the region with temperatures warming back to at and above seasonal levels into the end of the work week. However, breezy conditions, especially through the afternoon and early evenings, will lead to continued critical to near critical fire weather conditions, with Fire Weather Watches and Red Flag Warnings likely needed across portions of south central and southeast Colorado through the end of work week. Model solutions begin to diverge later Saturday and into early next week, with a new upper-level disturbance possibly passing to our north which could serve to knock temperatures back down and bring in some more unsettled weather. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 344 PM MDT Tue Apr 12 2022 VFR conditions are expected for all three sites, KCOS, KPUB, and KALS for the remainder of the TAF period. Westerly and northwesterly winds are beginning to diminish, and will weaken to below 35KT by 02Z tonight. Lighter northwesterly winds will remain in place through the overnight hours, with midlevel clouds moving in by tomorrow morning. Westerly winds are expected to pick back up towards the end of the TAF period, around 16-18Z on Wednesday morning, but are not expected to be as strong as today. && .PUB WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon to 7 PM MDT Wednesday for COZ224- 226>237. Winter Weather Advisory until noon MDT Wednesday for COZ058-059- 061. Winter Storm Warning until noon MDT Wednesday for COZ060. && $$ UPDATE...KT SHORT TERM...RODRIGUEZ LONG TERM...MW AVIATION...EHR/RODRIGUEZ
Area Forecast Discussion
National Weather Service Blacksburg VA
815 PM EDT Tue Apr 12 2022 .SYNOPSIS... A stalled front will retreat northward tonight. Warm and muggy conditions are expected Wednesday before a strong cold front approaches the region Thursday. Dry weather with high pressure Friday and Saturday before another disturbance early next week. && .NEAR TERM /THROUGH WEDNESDAY NIGHT/... As of 545 PM EDT Tuesday... Forecast remains on track for tonight, no significant changes made for the evening update. Showers in the NC mountains and foothills are slowly dissipating, and mid and high level clouds continue to move across the area. Previous discussion as follows... As of 235 PM EDT Tuesday... Mid to high level clouds remain along with warm temperatures this afternoon. An isolated shower chance remains over the mountains... Overall most of the light shower and sprinkle activity has come to an end across our region with the exception of the North Carolina mountains/foothills. Hi-res guidance from the HRRR, ARW, and NAMnest try to hold onto a few lingering showers in these locations as well as a couple hit or miss showers over the western mountains this afternoon with our shortwave disturbance working east out Tennessee. Coverage will be relatively sparse with our stalled front draped over northern Virginia and back into the southern Ohio River Valley. This stalled boundary will retreat further north as a warm front later today and into tonight with low pressure ejecting east out of the Upper Midwest region. As a result, our area will be open for business with a steady dose of moist southwesterly flow feeding in. Meanwhile weak upper level ridging at 500 mb will build into the region tonight and for the first half of Wednesday allowing rain chances to decrease. Rain chances do return for some during the second half of although coverage once again will be isolated. The 12z NAMnest, HRRR, and ARW illustrate the potential for prefrontal shower activity Wednesday afternoon and evening as a piece of shortwave energy races ahead of the front. Did take this into account with 15 to 30 percent PoPS confined to southeast West Virginia and the Alleghany Highlands Wednesday afternoon and evening. Also left a mention of thunder in for the mountains Wednesday afternoon since enough instability looks to be generated from filtered sunshine, warm temps, and increased humidity. Most of the activity looks to remain in the mountains with lower confidence for an isolated shower or storm further east Wednesday afternoon. As for temperatures, we look to remain 5 to 15 degrees above average through the period. Highs today will be similar to Monday with upper 60s and 70s over the mountains to near 80 further east. Temperatures will be tapered a bit due to excess cloud cover especially over the mountains where filtered sunshine may take longer to poke through. Wednesday will be our warmest day of the next seven days ahead and will feel more like a day to jump in the pool or float on the river with highs around 80 degrees. Humidity will also be on the uptick as dewpoints climb into the mid to upper 50s Wednesday afternoon Confidence remains high in the near term period. Leaned toward the ARW and HRRR for cloud cover and precipitation chances today through Wednesday. Both of these models kept us drier in the near term as convection flourishes to our south and west. They also hold mid to high level clouds in longer with better opportunities for sunshine during the afternoon and evening hours especially east of the Blue Ridge Parkway. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... As of 235 PM EDT Tuesday... Showers/few thunderstorms Thursday but still mild. Seems models are speeding up slightly the fropa Thursday, and this may impact instability in the east if it clouds up faster. Still a decent shortwave/vort moving across that morning but overall am not too impressed with severe chances as better instability will be south across southern NC into SC, but still enough to warrant thunder chances mainly east of the Blue Ridge Thu afternoon. Lingering showers in the piedmont Thursday evening then high pressure builds in Friday with dry and mild weather. High pushes to the coast Friday night with return flow ahead of warm front and approach of another weaker front from the west may bring a few showers to the mountains by Sat morning. Warm lows Wed night in the 50s with low 60s east. Highs Thursday will range from the mid to upper 60s mountains to mid to upper 70s piedmont. Cooler behind front but still warmer than normal Thu night with 40s areawide, then warming back into the 60s and 70s Friday. Forecast confidence is above average on temps/winds and sky cover and mainly above average on pops, but average on thunder chances. && .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 100 PM EDT Tuesday... Mostly dry weekend, then chance of showers and turning cooler. ECMWF/GFS/Canadian have differences again today but are close enough to give an idea about this period. The weekend overall looks mostly dry aside for some fast moving shortwaves in westerly flow with broad trough in place. Saturday looks to be the mildest day with highs in the 60s in the mountains to 70s piedmont. Easter Sunday, the trough deepens with high pressure building in from the north while front stalls out across the Gulf Coast states. Cannot rule out a few shower in the southwest mountains as inverted trough sets up, but overall should be pretty good day to be outside doing an easter egg hunt. After a typical mid April cool start in the 30s and 40s, temperatures will rebound to the 60s for most, with 50s in the WV mountains. Monday shows another 5h low/trough pushing across the upper MS Valley into the TN Valley. Differences exist on the strength of this system, with the ECMWF the strongest. The front to our south lifts back north as a warm front while a surface low moves into the Ohio Valley. Monday could be tricky on highs as rain chances increase ahead of the warm front and surface high moves off the mid-Atlantic coast. Have leaned toward the 00z ECMWF in our typical wedge area from southeast WV to the piedmont of VA north of Danville, with highs in the 50s, with some 40s along the ridges, while milder temperatures in the lower to mid 60s reside along/south of the VA/NC border in the piedmont and in the mid 50s to lower 60s in the southwest VA mountains/NC mtns. Given discrepancies in the models still, leaning toward keeping pops capped at chance 30-50. Using a blend of models, will see a cold front work across Tuesday. Cooler air may allow for some high mountain snow showers but at the moment nothing of consequence. Low temperatures will be close to normal in the 30s mountains to lower 40s piedmont. Cooler highs Tuesday ranging from he upper 40s to lower 50s mountains to upper 50s to mid 60s east. Forecast confidence is average on rain chances early next week and temperatures, but slightly above average this weekend. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... As of 800 PM EDT Monday... Mid and high level clouds continue to move through the area. Conditions at TAF sites have improved to VFR and are expected to remain VFR through Wednesday morning. Scattered to overcast high level clouds will return to the area Wednesday, before skies start to clear Wednesday afternoon. Overnight, winds will decrease and turn to the south, before becoming more southwest Wednesday afternoon ahead of an approaching front. Winds speeds will be between 10 to 20 knots, with the stronger winds along the higher elevations. Gusty winds expected Wednesday afternoon and evening, around 15 to 25 knots. Lingering moisture in the mountains of SE West Virginia may lead to the development of fog near KLWB Wednesday morning for a few hours. Otherwise, Wednesday looks to be mostly dry, with some chances of intermittent showers and storms, mainly west of the Blue Ridge, in the afternoon and evening hours as the cold front approaches. Average confidence for ceilings, visibilities, and wind through the TAF period. Lower confidence for timing of precipitation associated with the cold front. Extended Discussion... The best opportunity for MVFR to IFR conditions appears to be on Thursday as a cold front swings through. Precipitation chances at most of the TAF sites are isolated to scattered, with higher chances -SHRA/-TSRA at KLWB and KBLF. Expect areas of MVFR/IFR in -SHRA/-TSRA with LAMP probability guidance indicating LWB and BLF as the most likely candidates for sub-VFR Wednesday and Thursday. The front looks to clear the area Thursday afternoon and evening with brief high pressure settling in for Friday. Another chance for sub-VFR conditions is likely a possibility for the weekend ahead. The winds shift back toward more of a westerly direction while still remaining gusty behind the front Thursday. Lighter winds are expected Friday as high pressure builds in. Another front looks to cross the area on Saturday, before another round of high pressure to end the weekend. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...ET NEAR TERM...ET/AS SHORT TERM...WP LONG TERM...WP AVIATION...AMS/ET/AS
Area Forecast Discussion
National Weather Service San Angelo TX
622 PM CDT Tue Apr 12 2022 ...New AVIATION... .SHORT TERM... (This evening through Wednesday) Issued at 222 PM CDT Tue Apr 12 2022 As of 2:30 PM...the dryline was situated roughly along and east of line from Stamford to San Angelo to Junction line. Scattered showers and thunderstorms have developed east of the dryline across our eastern counties. A severe thunderstorm warning has already been issued on the storm currently in northern Coleman County. Given the current environment- ML CAPE values of 2000-2500 J/KG and mid level lapse rates of 8 degrees C/KM per current RAP analysis- additional strong to severe thunderstorms are possible through the afternoon and evening hours for the far eastern Concho Valley and Heartland. The bulk of the activity should exit our county warning area by around 6-7 PM. For tonight will hold on to a slight chance of PoPs across our far southeastern counties as a Pacific front moves down into the area. Otherwise, lows will fall into the upper 50s to mid 60s. Wednesday will be much cooler compared to today behind the Pacific front. Highs will be in the upper 70s and 80s. The combination of very dry conditions (relative humidity values under 10%) and gusty west- northwest winds will lead to another day of critical fire weather conditions across the entire area. && .LONG TERM... (Wednesday night through next Monday) Issued at 210 PM CDT Tue Apr 12 2022 Southerly return flow will build back in on Thursday, which should allow high temperatures to climb back into the upper 80s and low 90s by the end of the week. Otherwise, dry weather will persist. Over the weekend, there are some model differences, as the GFS shows a cold front coming down into Texas on Saturday, the ECMWF delays this front until Sunday. High temperatures could range from the mid 70s to the low 90s over the weekend, but for now, we trended with the warmer solution, given the dry soil conditions and overall warm pattern. Regardless, this could include some rain chances for our southeast counties over the weekend, but models are still struggling to get a handle on timing and location. && .AVIATION... (00Z TAFS) Issued at 621 PM CDT Tue Apr 12 2022 Expect strong west to northwest winds late Wednesday morning and afternoon with gusts to 35 knots. Otherwise, expect VFR for the next 24 hours. && .FIRE WEATHER... Issued at 258 PM CDT Tue Apr 12 2022 A Red Flag Warning remains in effect through this evening for the Big Country, Concho Valley, and the Northern Edwards Plateau. Gusty southwest winds combined with minimum relative humidity values 7-18 percent are resulting in critical fire weather conditions. A Fire Weather Watch remains in effect for all of west central Texas for Wednesday. After passage of a Pacific front early in the day, gusty west to northwest winds combined with relative humidity falling below 10 percent will result in critical fire weather conditions. Wind speeds are expected to be 15-25 mph with higher gusts. Elevated fire weather conditions are expected to continue through the rest of the week, during the afternoon hours. Warm and above normal temperatures will be combined with relative humidity values dropping to 6-12 percent Thursday, and 10-30 percent Friday. Winds will be from the south to southeast on Thursday, and mostly from the south on Friday. Overall wind speeds will be lower than what is occurring in the first half of this week. && .PRELIMINARY POINT TEMPS/POPS... Abilene 63 79 44 83 / 10 0 0 0 San Angelo 62 81 44 87 / 10 0 0 0 Junction 62 85 47 88 / 10 0 0 0 Brownwood 61 83 43 85 / 20 0 0 0 Sweetwater 63 76 46 83 / 0 0 0 0 Ozona 60 79 48 86 / 0 0 0 0 Brady 65 82 47 85 / 20 0 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 9 PM CDT this evening for Callahan-Coke- Crockett-Fisher-Haskell-Irion-Jones-Nolan-Runnels-Schleicher- Shackelford-Sterling-Sutton-Taylor-Throckmorton-Tom Green. Fire Weather Watch from Wednesday morning through Wednesday evening for Brown-Callahan-Coke-Coleman-Concho-Crockett-Fisher- Haskell-Irion-Jones-Kimble-Mason-McCulloch-Menard-Nolan-Runnels- San Saba-Schleicher-Shackelford-Sterling-Sutton-Taylor- Throckmorton-Tom Green. && $$ SHORT TERM...42 LONG TERM....SK AVIATION...21