Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/09/24


Area Forecast Discussion
National Weather Service Cleveland OH
1030 PM EDT Wed May 8 2024 .SYNOPSIS... Low pressure will lift a warm front north across the region late tonight into Thursday. Unsettled weather will persist through the end of the week and into the weekend. && .NEAR TERM /THROUGH FRIDAY/... 9:50 PM Update: Only minor adjustments needed to the forecast. Slowed down the onset of POPs a bit. The exact coverage of showers very late tonight through Thursday morning remains somewhat uncertain, especially across North Central and Northeast OH. As mentioned below, forcing isn`t very strong through Thursday morning and there will be relatively dry northeast low-level flow in place. However, some models (such as the 3km NAM) have rather widespread rain Thursday morning. Recent HRRR runs have trended towards filling in more showers across most of North Central and Northeast OH. Still feel the greatest shower potential overall will spread from west to east from around midday through the early evening, though did increase POPs just a bit Thursday morning across North Central and Northeast Ohio. Hit everyone with a categorical (80%+) POP at some point Thursday afternoon or early evening with most areas peaking at 90-100%, as there`s decent agreement everyone will see measurable rain at some point in the afternoon or early evening. Previous Discussion: High pressure has allowed for a period of dry weather today. It was a bit breezy this afternoon with wind gusts around 25 mph, though expecting these gusts to diminish around sunset tonight. As the high exits the region tonight a warm front lifts northeastward and will allow for high level clouds to begin to filter in tonight. Confidence in shower coverage early tomorrow morning along the front has decreased since the last forecast update as frontogenesis and upper level support has backed off slightly. The better chance for widespread rain showers and embedded thunder comes late Thursday morning and early afternoon as the parent low glides east across Northern Ohio. This low will take its time exiting the region and will keep rain chances in the forecast through the end of the period. Can`t rule out some nuisance flooding with any pockets of heavier rainfall through the end of the week, but overall impacts should be minimal. Slightly above normal overnight lows tonight in the mid 50s for most, upper 40s to lower 50s in Northwest Pennsylvania. Highs tomorrow will be cooler as they will rise into the upper 50s to lower 60s. Near normal overnight lows Thursday night in the mid/upper 40s. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... We start the short term period with an upper-level trough overhead. Isolated to scattered rain showers may linger across the area on Friday especially the eastern part of the forecast area before that trough departs to the east. Upper-level ridging and surface high pressure very briefly builds in Friday night before another upper- level trough and associated surface low move southeast across the Great Lakes region. Periods of rain showers are expected through the day Saturday, with mean QPF around 0.25" (some spots lower, other areas as high as 0.5"). Isolated thunderstorms may be possible during the afternoon/evening hours. Isolated to scattered rain showers may linger into Saturday night, mainly for the eastern part of the forecast area. Temperatures will be below normal through the short term period with highs around 60 and lows in the 40s. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... Broad weak upper-level ridging builds in, although several weak upper-level shortwaves move across the area through the week, resulting in low PoPs maintaining through the long term period. Temperatures gradually warm up through the week with highs in the low 70s increasing to mid-upper 70s by Wednesday. && .AVIATION /00Z Thursday THROUGH Monday/... VFR will continue through early Thursday. Thursday morning will see a warm front will lift out of central OH, though it likely won`t quite reach FDY/MFD/CAK. During the afternoon and evening on Thursday this front will begin sinking back southeast as low pressure develops over the Ohio Valley. An initial push of showers will try pushing in ahead of the warm front late tonight into early Thursday, though this activity will be fairly hit/miss and light so not expecting many restrictions with the showers. Handled with a VCSH mention where needed. A period of MVFR ceilings may still develop north of the warm front Thursday morning, though dry northeasterly flow will try to counteract it. Limited any MVFR ceilings Thursday morning and afternoon to TOL, FDY and MFD, and even at these sites only prevail them for a few hours. Can`t rule out brief MVFR at CAK either but confidence is lower. Showers will become more numerous and a bit more intense from west to east later Thursday morning into the afternoon. The greatest potential for vsby restrictions will be at CAK and YNG, where there`s also a low risk of thunder Thursday afternoon and early evening. Otherwise, some additional non-VFR ceilings may begin developing near or just after the end of the current TAF period Thursday evening. West-northwest winds are subsiding to less than 7 knots this evening. Winds will turn northeast overnight at 5 to 10 knots and continue through Thursday. Locations along the lakeshore (including TOL/CLE/ERI) may see stronger northeasterly winds increase to 12-15 knots accompanied by gusts 20-25 knots Thursday afternoon. Outlook...Non-VFR likely at times in showers and lower clouds Thursday night into Friday morning. Non-VFR possible in showers and storms Saturday into Saturday night. && .MARINE... Low pressure over northern Missouri gradually moves east tonight and tomorrow across the Ohio Valley, with easterly winds strengthening to 20 to 25 knots during the day Thursday. As the low moves east towards the mid-Atlantic region, winds gradually veer to northeast, north and northwest Thursday night and Friday morning. Winds of up to 25 knots and waves of 3 to 6 feet will result in a small craft advisory for this period for all of our Lake Erie nearshore waters. Another weak low moves southeast across the Great Lakes region on Saturday. There could be periods of stronger winds to 15 knots, but it`s a low chance of small craft advisory at this point. The wind and wave forecast looks to be mild Sunday onward as there will be no strong low of high pressure systems. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. NY...None. MARINE...Small Craft Advisory from 8 AM Thursday to 4 AM EDT Friday for LEZ142-143. Small Craft Advisory from 8 AM Thursday to 10 AM EDT Friday for LEZ144>149. && $$ SYNOPSIS...Iverson NEAR TERM...Iverson/Sullivan SHORT TERM...Saunders LONG TERM...Saunders AVIATION...Sullivan MARINE...Saunders
Area Forecast Discussion
National Weather Service Corpus Christi TX
632 PM CDT Wed May 8 2024 ...New AVIATION... .SHORT TERM... (Tonight through Thursday night) Issued at 218 PM CDT Wed May 8 2024 Key Messages: Moderate to Major risk of heat-related impacts, Heat Advisory in effect for inland Nueces and inland Kleberg Thursday Haze from near-surface smoke lingers and worsens outdoor exposure health risk A weak dryline is currently located right along the Rio Grande up to Del Rio and northeastward. This is expected to move into the Brush Country over the next couple of hours, reducing humidity out west. The greatest heat index values are still expected over the southern Coastal Bend including inland Nueces, inland Kleberg, and Jim Wells Counties. There`s still a few hours of heating potential left in breaks of clouds in combination of dewpoints near 80 to cause heat index values of 110. Therefore, will maintain the Heat Advisory through 7 PM this evening. Haze has been observed across all of South Texas through the day today and will continue through Thursday night. Smoke guidance from the HRRR shows increased near-surface smoke concentration advecting from Central America up to South Texas. Weakening winds with high dewpoints will also lead to a threat of patchy fog in combination with the haze. Lows tonight will flirt around the record high minimum values for the 7th day in a row. Although the dryline retreats northwestward tonight, it will push back through most of the Brush Country on Thursday and force clouds to be focused right along the coast to the Victoria Crossroads in the afternoon. The dryline will allow air temperatures to climb around 105-108 over the Brush Country. How high the heat index values get to Thursday will be dependent on the eastward extent of the dryline. As of now, it is expected to halt just west of inland Kleberg and inland Nueces counties, resulting in a medium chance of at least 110 heat indices in the afternoon. Therefore, have issued a Heat Advisory for those two county portions from 1-7 PM Thursday. && .LONG TERM... (Friday through next Tuesday) Issued at 218 PM CDT Wed May 8 2024 Key Messages: Weak cold front Friday morning Rain chances return this weekend Models are beginning to come into better agreement showing a weak cold front pushing through the region Friday morning providing some relief from the recent above normal temperatures. While rain chances are low with the cold front, rain chances will increase Saturday as the front retreats northward as a warm front ushering in PWAT between 2.0-2.1". Low end chances (20% or less) for rain Saturday will increase to a medium (30-55%) chance Sunday and Monday as a shortwave moves across the region interacting with the abundant moisture. While the Victoria Crossroads appears to be the early favorite for the best chances of rain, the whole county warning area will be in play especially Monday, when models show a surface low moving across the area. Rain chances will quickly taper off early next week as we begin to dry out. Temperatures in the wake of the front will drop into the 80s Friday afternoon and Saturday with most of the region in the lower to upper 80s. Temperatures will begin to increase once again Sunday before climbing back into the lower to upper 90s early next week into mid- week. Lows throughout the long term period are expected to remain steady in the lower to mid 70s. && .AVIATION... (00Z TAFS) Issued at 616 PM CDT Wed May 8 2024 VFR ceilings in place over all terminals with MVFR visibilities in ALI and VCT as residual smoke from Central America has caused continuous hazy conditions across South Texas. The presence of haze and reduced visibilities is likely to continue through tomorrow as depicted by HRRR Smoke guidance. Ceilings will drop to MVFR/IFR tonight with occasional LIFR over ALI, CRP, and VCT between 09-14Z. In addition to haze, patchy fog will also be likely as low dewpoint depressions will coexist with winds less than 10 kts. A weak dryline will push into the Brush Country from the west Thursday afternoon, leading to a weak northwesterly winds at LRD, COT, and ALI. Weak southeasterly winds will persist elsewhere. && .MARINE... Issued at 218 PM CDT Wed May 8 2024 Weak to moderate onshore winds can be expected through Thursday night along with patchy fog in the late night and early morning hours. In addition to patchy fog, haze from near-surface smoke southward will likely continue before our next front passes. A cold front will move offshore Friday morning. Weak to moderate northeast winds Friday will strengthen to moderate to strong Saturday as it shifts to the east. By early next week, winds will shift to the southeast and remain moderate. Rain chances return Saturday with a low chance and increases to a medium chance Sunday and Monday. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 78 96 77 89 / 0 0 0 10 Victoria 76 92 73 90 / 0 10 0 10 Laredo 78 108 75 95 / 0 0 0 20 Alice 76 101 75 91 / 0 0 0 20 Rockport 78 87 77 88 / 0 0 0 10 Cotulla 77 105 75 93 / 0 0 0 10 Kingsville 77 100 76 89 / 0 0 0 10 Navy Corpus 78 90 78 87 / 0 0 0 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...Heat Advisory until 7 PM CDT this evening for TXZ241>243. Heat Advisory from 1 PM to 7 PM CDT Thursday for TXZ242-243. GM...None. && $$ SHORT TERM...EMF LONG TERM....JCP AVIATION...KRS/98
Area Forecast Discussion
National Weather Service Cheyenne WY
449 PM MDT Wed May 8 2024 .KEY MESSAGES... - Precipitation chances increase later today and overnight with accumulating mountain snowfall expected. Scattered showers continue into the day Thursday. - Warming trend likely headed into the weekend with the return of above normal temperatures for mid-May. && .SHORT TERM /THROUGH THURSDAY/... Issued at 323 PM MDT Wed May 8 2024 The low pressure center spinning around in the Dakotas that was responsible for the windy last few days, has begun to retrograde back to the southwest, leading to another round of precipitation for the CWA. As the upper-level low pushes into the CWA this evening, precipitation chances across the area will increase. Clouds have steadily been increasing across the CWA based on visible satellite imagery. Regional radar and observations also show some light rain beginning to creep into the northern tier of the CWA. As the low continues its trek across the CWA overnight, winds will turn more northerly leading to upslope flow and enhanced snowfall amounts on north-facing slopes. The North Laramie Range will see the best enhancement and highest snowfall totals. A Winter Weather Advisory is already in place here. Did go ahead and expand the Advisory until noon tomorrow as the newest Hi-Res guidance suggests persistent, steady precipitation at least through the morning hours. Northern slopes of the Snowy Range could also pick up a quick 6 inches of snow tonight into Thursday morning. Another area to watch will be Laramie and Rawlins. GFS and ECMWF ensembles show about 1 to 3 inches of snow in these cities tonight into tomorrow morning. Decided to keep totals lower than this as the HRRR show mostly scattered and quick moving showers. However, if accumulation does occur, this could lead to some slippery roads for the morning commute. Most locations east of the Laramie Range will sustain warmer temperatures overnight, leading to rain showers, with the chance for a few flakes to mix in. Widely scattered rain and snow showers will continue into the day Thursday as a final vorticity max behind the upper-level low lingers across the CWA. The mountains could pick up an additional inch or two during the afternoon hours, but warmer temperatures should keep most of the snow out of the valleys and plains. Some rumbles of thunder could also be possible as non-zero CAPE values exist across much of the area. Showers will become less numerous Thursday night as the low parks itself over the Four Corners region. Headed into Friday, expect a warmer and less active day. A few isolated showers could be possible over the high terrain as the low over the Four Corners sends weak disturbances northward. Weak southerly flow will allow 700 mb temperatures to rebound back to around 0C. This will lead to high temperatures near to slightly below average for this time of year. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... Issued at 323 PM MDT Wed May 8 2024 An unsettled long term pattern is expected across southeast Wyoming and western Nebraska. An upper-level low will continue to rotate around the Four Corners Region and points northwest throughout evening Friday and into the day Saturday. By Sunday, this upper- level low will be caught up into the upper-level jet and will rapidly progress to the east and finally leave this region of the CONUS. Prior to this, with the low rotating around the Four Corners Region, a vorticity lobe will traverse from northern Wyoming southward through much of the CWA. This vorticity lobe will provide some synoptic lift for the CWA during the afternoon hours Saturday. With this synoptic lift, but minimal assistance at the 700mb level, some showers and potentially thunderstorms will be possible across the region. Modest MLCAPE values around 400 J/kg will be present across the region, further supporting a thunderstorm or two on Saturday. Behind this system, upper-level ridging will build across the western CONUS and slowly migrate east throughout the day Sunday and into the early morning hours Monday. The ridge axis will not be directly overhead on Sunday, but temperatures will increase into the mid-60s and mid-70s across the area. Once again, with vorticity lobes moving overhead as they traverse through the ridge, synoptic lift will be present across the region along with the potential for modest MLCAPE values once again. The region could see isolated showers Sunday in the afternoon. A similar setup is expected for Monday, but the upper-level ridge axis will be closer to the region, allowing temperatures to warm into the mid-60s to upper-70s across the region. A pattern shift is expected by mid-week as an upper-level trough begins to dive into the northern CONUS on Tuesday. As this trough moves just north of the CWA, height gradients will increase slightly leading to the potential for elevated winds Tuesday. As of now, these winds only look to be elevated and not near high wind criteria. A cold front will move across the region Tuesday into Wednesday leading to slightly cooler temperatures Wednesday across the region. Behind the front, northwesterly winds will pick up once more and continue the potential for elevated winds throughout the day. With this cold front pushing through, rain showers and thunderstorms will be possible again on Tuesday into Wednesday. They do not look likely to be severe at this time, as MLCAPE values only approach the 400 J/kg level. Overall, enjoy a warm week in the forecast with nearly daily chances for isolated showers and the potential for some thunderstorms. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 443 PM MDT Wed May 8 2024 A tricky aviation forecast will begin to take shape this evening through Thursday morning. VFR CIGs will transition to MVFR/IFR fluctuations due to -SHRA/-SHSN, which will also create VIS reductions at times. Winds are anticipated to be below 12 knots overnight for all terminals, before picking up in the NE Panhandle to 20-25 knots. Please see individual TAFs for further information. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Winter Weather Advisory until noon MDT Thursday for WYZ103. NE...None. && $$ SHORT TERM...SF LONG TERM...AM AVIATION...BW
Area Forecast Discussion
National Weather Service Sioux Falls SD
1041 PM CDT Wed May 8 2024 .KEY MESSAGES... - Widespread showers with embedded thunderstorms east of I-29 will transition to scattered showers overnight into Thursday morning. Some threat for localized heavy rainfall resulting in additional rises on some rivers/streams, mainly in northwest Iowa/southwest Minnesota. - Warmer and mainly dry conditions move in for the weekend. Continued warm with renewed rain chances by mid week. && .DISCUSSION... Issued at 239 PM CDT Wed May 8 2024 Showers and thunderstorms should increase in coverage across parts of northwest IA and southwest MN through the afternoon as well as near highway 14. A small axis of instability is expected this afternoon in this area. Overall instability not that high, but with the freezing level around 6-7 kft it will be pretty easy to get some smaller hail. Still looks like an environment supportive of hail up to half dollar sized with only weak shear expected. One other thing to watch will be the potential for funnels and landspouts. Steep low level lapse rates and lighter winds near a surface boundary may support this type of activity. With only marginal instability and weak shear any activity like this should be short lived. While some stronger winds gusts will be possible the HRRR and HREF both indicating gusts should generally be 50 mph or lower. The upper level low pressure shears out and sags south tonight into Thursday. Scattered showers will remain possible during this time, but instability is quite a bit less so even lightning will likely diminish quite a bit after about 10 pm. Lows will be seasonally mild in the mid 40s. While the main synoptic forcing settles south, model soundings do show some weak instability near the top of the mixed layer on Thursday which may support some isolated showery activity. Temperatures will also be a touch cooler as winds turn northerly and some diurnally driven cloud cover is expected to develop. Highs should still be in the 60s. Friday and Saturday will be dry and mild as northwest flow aloft weakens and westerly flow in the low levels is in place. By Sunday a weak wave in this flow could bring some isolated activity but for now this looks to be low impact. Highs should gradually warm from the lower 70s Friday to the lower 80s by Sunday. West to northwest flow aloft is expected Monday and Tuesday which should lead to a couple of warm days. While this pattern will not be a wet one, some spotty shower and thunderstorm activity will be possible. The most agreement appears to be Monday night into Tuesday morning. Wednesday into Thursday the models are indicating a strong upper level jet max diving into the Northern Rockies which should turn upper level flow more southwesterly and bring a better chance for showers and thunderstorms. && .AVIATION /06Z TAFS THROUGH 06Z FRIDAY/... Issued at 1041 PM CDT Wed May 8 2024 Thunderstorms near/east of US Highway 59 in northwest Iowa are expected to weaken further through the remainder of tonight, with thunder not expected to impact TAF locations. MVFR ceilings and brief MVFR visibility will be associated with the area of more persistent rain east of I-29 through early Thursday. Additional scattered showers will slide back to the south across southeast SD through Thursday morning, with mainly VFR conditions expected. The threat of thunder with this activity is too low to include in TAFs, though is non-zero and will be monitored. Any showers may still produce gusty winds, though prevailing winds will generally be at or below 15kt into Thursday morning, with occasional north-northwest gusts to around 20kt during the late morning and afternoon. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && $$ DISCUSSION...08 AVIATION...JH
Area Forecast Discussion
National Weather Service Grand Rapids MI
928 PM EDT Wed May 8 2024 .KEY MESSAGES... - Rain Thursday - Rain Expected Saturday - Lower Certainty Pattern Into Next Week && .UPDATE... Issued at 926 PM EDT Wed May 8 2024 Trends in the latest HRRR suggest this dry air currently in place will play a more significant role in the timing and amount of precipitation we end up seeing. Through 12z, there`s almost no qpf seen in the CWA. Based on this, I trended POPs downward for tonight and also shifted them further south, closer to the moisture. && .DISCUSSION... Issued at 254 PM EDT Wed May 8 2024 - Rain Thursday Clear skies this evening will give way to increasing clouds tonight as low pressure over Oklahoma begins to get caught up in the upper flow over of the northern MS Valley trough. Given the east-west elongated nature of the trough, it will take at least 24 hrs for the low and its precipitation to move out of the cwa. Model trends track the low across the north side of the OH Valley tomorrow developing rain in the far southern cwa around 12z and then moving north. Little in the way of instability means thunder should stay south of the cwa. QPF totals have trended down a bit and range from a couple of hundredths near US-10 to around a half in near I-94. Light rain will end Friday evening. Below normal temperatures are expected Thursday with highs in the upper 50s. There could also be some patchy frost in low lying areas near US-10 Thursday night as temperatures fall into the upper 30s there. - Rain Expected Saturday Friday brings dry weather to West Michigan as high pressure and ridging aloft shifts through the Central Great Lakes. It will be slightly cooler than normal with highs in the low to mid 60s. Our next chance of rain begins early Saturday as a shortwave drives a surface low across the region. Rain showers are expected with the best coverage Saturday morning as the low itself crosses the area. However, some diurnal enhancement on the backside of the low is possible Saturday afternoon as the upper-level cold pool passing overhead given steep mid-level lapse rates in the 7C-8C range. If we can get a shower with a better updraft, those lapse rates suggest that isolated thunderstorms are possible. - Lower Certainty Pattern Into Next Week Dry weather is expected for the day on Sunday as a brief period of shortwave and upper-level ridging slides through the state. Precipitation chances do increase somewhat Monday as a shortwave and cold front enter the region, however the timing and placement of these features is uncertain. Ensemble means and deterministic guidance do suggest a longwave trough develops but there remains notable spread in model guidance as to the specifics of how the pattern evolves. This gives lower confidence as to forecast details in the days 5-7 timeframe. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 741 PM EDT Wed May 8 2024 A storm system will track in from the west later tonight and persist into Thursday afternoon. The low levels are projected to struggle saturating early on so we will keep conditions at VFR. However as the rain picks up in intensity, mainly for the southern TAF sites of KAZO, KBTL and KJXN, the visibility could come down to MVFR levels. During the afternoon hours as the region ends up on the backside of the departing storm system, condition should return to VFR levels. Overall the area will be on the north side of this wave so the winds will be out of the east. && .MARINE... Issued at 254 PM EDT Wed May 8 2024 East winds will develop tonight and could be gusty for a brief period during the late morning/early afternoon Thursday but will hold off on a headline due to the limited nature of it. Colder air moving southeast early Saturday may result in 3-5 foot waves south of Grand Haven for a period as well. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ UPDATE...MJS DISCUSSION...04/Thomas AVIATION...MJS MARINE...04
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1134 PM EDT Wed May 8 2024 .SYNOPSIS... Showers and thunderstorm activity will be more numerous ahead of a strong cold front tonight into Thursday, with severe storms possible. The cold front pushes east early Friday morning but another system approaching out of the south may bring shower and thunderstorm chances back during the day on Friday. Drier conditions and below normal temperatures return for the weekend. && .NEAR TERM /THROUGH THURSDAY/... As of 1126 PM EDT Wednesday: Over the past two hours, we have been watching supercells come off the Cumberland Plateau and begin to congeal and grow upscale into more of a convective line across the Great Valley of TN. The storms will likely remain strong to severe as they cross over a sfc-based CAPE plume of 1000-1500 J/kg that exists along the TN/NC line, but east of the spine of the mtns, the environment is much less hospitable. The air mass east of the Blue Ridge for the most part did not recover, and has only 500 J/kg at best, which will keep most of the activity in check. The main concern is the area from the SW mountains down across northeast GA and the Savannah R basin. An old outflow boundary from the afternoon convection stalled across this area and a CAPE gradient of 500-1500 J/kg persists, with enough effective shear and low level shear to allow storms to maintain supercell characteristics. All threats are in play across this area, so the SPC issued a new Tornado Watch to cover the possibilities. We are especially interested in the cells crossing north Georgia as of 03Z. This activity will traverse the fcst area thru the late night hours and feel the HRRR has had a good and consistent handle on it. Another round of showers and thunderstorms may come in behind this one, but the severity will be even more restricted toward daybreak. Otherwise...for Thursday...not quite as warm but still mid 80s in the Piedmont. Slight Risk in place on Thursday but that`s as the convection slips south in the morning. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... As of 100 PM EDT Wednesday: For the Thursday night period, the 12z HREF and CAM consensus depicts just very limited and isolated deep convection lingering from whatever daytime activity redevelops, along with a smattering, but again limited response into the night and mainly confined to the mountains. Not unexpectedly, the pattern atop the SE CONUS remains dynamic into Friday as energy rounding the base of the upper trough will finally be again to shove lingering sfc frontal zone downstream of the cwfa. But before it does, we will be wary for the threat for tstm encroachment and redevelopment, along the front itself, and in addition, MCS/bowing cluster moving in from Georgia. Sensible weather will feature a shotgun mid-chance pop for Friday with isolated svr storms possible mainly SE of I-85. Will plan on overspreading the region with deep layered dry air within the broad downward vertical motion behind the departing s/wv axis Friday night. Expecting to be under a well mixed and more seasonable airmass within the deep cyclonic flow on Saturday featuring maximum temperatures close to climo. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... As of 315 am EDT Wednesday: A broad upper trough is expected to progress across the East through the weekend, with dry air/pleasant surface dewpoints supporting wide diurnal temp ranges...max temps averaging around normal and min temps a category or so below climo. By early in the work week, a split flow regime is expected to be in place across the eastern Conus, with a short wave ridge developing across the Southeast...downstream of a southern Great Plains upper low. Global models are at odds regarding the evolution of this feature, namely its interaction with the northern stream, and eventual impacts on sensible weather across the Southeast. For now, there`s enough of a signal to include chance PoPs across much of the CWA by Mon night/Tue. Temperatures are forecast to be very close to normal through the period. && .AVIATION /04Z THURSDAY THROUGH MONDAY/... At KCLT and elsewhere: VFR for the time being at all terminals, and that should hold into the late evening, hopefully through the end of busy operations. Most of the forecast area has rain-cooled air with some sct-bkn low VFR debris clouds. We may see some brief MVFR at KAND, but this is not likely and left out of the fcst. Wind will be generally light and modulated by numerous outflow boundaries across the region, so many places will have a variable direction for the evening, until a southerly flow can be re-established. We look to the west and await the next round of storms, which the HRRR brings into the mtns at 04Z and then quickly east through the pre-dawn hours. All terminals should see thunderstorms with this complex, so a 4-hr TEMPO was employed for the initial round. There could be a second round, or at least a trailing stratiform rain for several hours into the middle part of the morning. There should be some MVFR cloudiness lingering into the middle part of the day. Once we scatter the low deck, expect deep enough mixing for some occasional wind gusts from the SW thru the rest of the afternoon. Outlook: A system lifting out of the south my increase shower and thunderstorm chances again on Friday, but confidence on this remains low. Drier conditions can be expected this weekend. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...CSH NEAR TERM...PM/TDP SHORT TERM...CSH LONG TERM...CSH AVIATION...PM
Area Forecast Discussion
National Weather Service Louisville KY
1115 PM EDT Wed May 8 2024 .KEY MESSAGES... * Scattered severe storms possible this evening. All severe hazards will be possible. * Flooding concerns increasing for southern and central Kentucky. A Flood Watch is in effect through Thursday morning. * Below normal temperatures return by Friday and persist into the weekend. && .UPDATE... Issued at 1115 PM EDT Wed May 8 2024 The severe weather environment has weakened over the Bluegrass and areas east of I-65. The tornado watch has been cancelled over these areas. Over southern Kentucky, storms continue to entrain bringing large rain totals and flooding to these areas. Motorists are advised to use caution, flooded roads at night are very difficult to see. && .SHORT TERM /THROUGH THURSDAY/... Issued at 337 PM EDT Wed May 8 2024 ===================== This afternoon and evening ===================== A MCV is located near St. Louis this afternoon, evolving slowly eastward. An effective warm front/remnant outflow boundary extends SE through portions of western and southern KY, with sfc dewpoints near 70 F along and south of the boundary. Scattered thunderstorms have developed in south-central KY along the boundary and associated instability gradient. Portions of south-central KY have been the slowest to destabilize in the wake of morning convection and cloud debris. Sfc temperatures are only now warming into the lower 70s at BWG, with mid/upper 70s to near 80 noted across southern IN and the northern half of KY. Likely still have a shallow low-level inversion present across south-central KY, where ongoing impressive supercellular storms could be elevated. However, this is also along a boundary/instability gradient which continues to drift northeast with time. A long, straight hodograph above 1 km is also supporting splitting supercells which we have already seen with a left-mover tracking northeast through Ohio County and a right-mover now moving east across Warren County. Storms that move further to the right (E, ESE) will realize greater low-level SRH and have a better chance of producing a tornado. A Tornado Watch has been issued for portions of central and southern KY where the near-term tornado risk is highest - roughly southwest of a line from Brandenburg to Campbellsville. Further north and northeast, low-level winds are notably weaker and the tornado risk is lower. The scattered storm activity ongoing now is expected to continue to drift east and northeast with time, while increasing in coverage this evening. So while severe weather is still very much possible further north, such as along the I-64 corridor, the window for storms and severe weather is shorter. The most likely time frame for severe weather is now (3-4 PM) through Midnight. But areas further northeast, such as from Louisville to Lexington, have the best chance at seeing a severe storm from 5-11 PM EDT. Given the destabilizing airmass (1000-2000+ J/kg MLCAPE) and very strong effective deep layer shear (50-60 kt), supercellular storm modes are likely well into the evening hours. Increasingly larger clusters and perhaps bowing segments will be possible beyond 8 PM. All severe hazards remain possible through the evening hours, with the highest risk in the Tornado Watch area (this includes large hail, damaging winds of 70+ mph, and tornadoes. A Flood Watch also remains in effect for much of the area. Again, the highest risk for flash flooding is concentrated across the southwestern half of the CWA where the greatest thunderstorm coverage is anticipated. Will need to watch closely for any training along the boundary as it slowly lifts northeast. PW values are also highest, exceeding 1.5 inches, along the lingering boundary. 1-3 inches of rain will be possible, with the highest amounts across south-central KY. Localized higher totals of 3+ inches cannot be ruled out across south-central KY. ===================== Tonight and tomorrow ===================== A final band of showers and storms will likely push southeast across the region late this evening into tonight ahead of the cold front. Confidence in severe weather after Midnight is much lower, but localized damaging winds cannot be ruled out. Waning instability will help to limit the wind threat at ground level. This activity will likely weaken with time as it exits from NW to SE by the early morning hours. Thursday looks drier with morning lows in the 60s and afternoon highs near 80 F. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... Issued at 337 PM EDT Wed May 8 2024 By Thursday evening, the cold front responsible for recent inclement weather will be off to our east along with most, if not all, convective activity. Aloft, a positively tilted longwave trough will extend from the NE US to an upper low positioned over the Four Corners region of the SW CONUS. Embedded shortwave energy will propagate through the longwave pattern into the OH Valley during the day Friday, coupled with wrap-around moisture from the departing surface low, and resulting in lingering precip chances. GFS soundings suggest fog/stratus potential Friday morning; furthermore, 12Z NAM3k and HRRR soundings also show a saturated layer from just above the surface to around 800/750mb, indicative of the possibility of drizzle across southern Indiana and north central KY until late Friday morning. With the upper trough positioned over the OH Valley, temperatures through the weekend will be several degrees below normal, resulting in more of a Springtime feel: looking for daily highs in the upper 60s to low 70s through the weekend. Another shortwave will makes its way through OH Valley Saturday, bringing another chance of light showers as well as tightening the pressure gradient enough to produce some breezy conditions, with gusts expected in the 20-25 mph range Saturday afternoon. Low level ridging will simultaneously begin building into our region Saturday, which would suggest dry conditions for Sunday. Low amplitude upper level ridging will pass overhead to start the workweek, as the low level high center passes to our east. This leaves our region on the dirty side of the high with return flow and an uptick in low level moisture. Rain and storm chances return as early as Monday evening through Mid week. Not expecting a washout, but long range models` low temporal resolution have yet to resolve finer details. It`s worth repeating though that CIPS/CSU/SPC severe comparisons show no signs of severe weather during this timeframe. && .AVIATION /00Z TAFS THROUGH 06Z FRIDAY/... Issued at 800 PM EDT Wed May 8 2024 Strong to severe storms are currently scattered through the region. These storms will continue for the next few hours. At times, strong storms over the terminals could lead to variable and high winds and visibilities as low as 1-2SM. As we lose instability from daytime heating, these storms will begin to weaken. As the cold front approaches the region from the northwest, a line of showers and embedded storms will move through the region. This line will mostly bring SHRA to the I-64 terminals and VCTS to BWG for a few hours. In the overnight hours, winds will be mostly from the south and slowly veer to the southwest. In the early morning hours, CIGs will lower to MVFR as the cold front moves through the terminals. Behind the front, winds will veer to a northwesterly direction and CIGs will improve quickly. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...Flood Watch until 8 AM EDT /7 AM CDT/ Thursday for KYZ023>043- 045>049-053>057-061>067-070>078-081-082. IN...Flood Watch until 8 AM EDT /7 AM CDT/ Thursday for INZ077>079- 084-089>092. && $$ UPDATE...SRM SHORT TERM...EBW LONG TERM...CRG AVIATION...SRM
Area Forecast Discussion
National Weather Service Memphis TN
626 PM CDT Wed May 8 2024 ...New AVIATION... .SYNOPSIS... Issued at 247 PM CDT Wed May 8 2024 Showers and thunderstorms will increase and intensify tonight under a Moderate Risk for severe weather. Destructive winds, very large hail, tornadoes, and heavy rainfall are all possible. The main line window of severe weather is from 7 PM tonight to 6 AM tomorrow morning. After the line exits the region, most of the region will see dry conditions. North Mississippi may see a shower or thunderstorm tomorrow afternoon associated with a upper level disturbance, but a beautiful and dry weekend is in store. Our next chance of widespread showers and thunderstorms will come early next week. && .DISCUSSION... (This evening through next Tuesday) Issued at 247 PM CDT Wed May 8 2024 Convection has started to fire up across West Tennessee as of 2 PM. Pinched in the warm sector of two boundaries is the Mid-South which has allowed convection to initiate. Showers and thunderstorms will become more widespread and increase in intensity this evening ahead of a strong cold front. Strong upper level divergence with a primed environment will allow convection to intensify later tonight. Mesoanalysis from the RAP shows plentiful CAPE values 3000-4000 J/kg, lapse rates around 7 C/km that will continue to steepen, 40-50 kts of effective shear, and curvature to hodographs. The threats for tonight`s severe weather threat include destructive winds of 80+mph, quick spin up tornadoes that could be strong, and significant hail of 2" or greater. Most likely timing for the main line arrival is as early as 6 PM in northeast Arkansas, the Missouri Bootheel, and northwest Tennessee. The main severe weather window for the entire Mid-South is 7 PM to 6 AM Thursday. Once the sun sets, the LLJ will begin to intensify and quickly push the line on a south/southeast track across northwest Alabama and northern Mississippi. A Flood Watch is in effect for the northeast corner of our CWA in West Tennessee (Benton, Carroll, Weakley, and Henry counties) as this area has higher probabilities (40-50%) of receiving 2 or more inches of rain tonight. Elsewhere, generally 1.5-2" is forecast through tomorrow morning. Locally higher amounts are possible in any intense updrafts. As storms have begun to fire up as mentioned above, be sure to secure loose outdoor items, prepare for power outages, and have your safe place ready to shelter in when a warning is issued. It is not safe to be in a manufactured home this evening. Please reach out to friends, family, neighbors, or local city/county officials to locate your nearest storm shelter or stay with a friend for a safe space. The line of storms should clear the area by 7 AM at the latest Thursday morning. Another upper level disturbance from the Gulf Region may bring some showers and thunderstorms Thursday afternoon and evening, mainly along and south of Interstate 40. Some thunderstorms may be strong to severe. On the brighter side, the weekend looks beautiful with dry and seasonable temperatures in the 70s. Temperatures and dewpoints will be on a slow rise as return flow settles in ahead of our next system. Widespread showers and thunderstorms will return Monday afternoon into Tuesday. Currently, no severe weather is anticipated with this system. DNM && .AVIATION... (00Z TAFS) Issued at 601 PM CDT Wed May 8 2024 Short-term concerns in the 00Z TAF set continue to be the timing of showers and thunderstorms affecting TAF sites tonight. Latest model trends suggest the best potential for TS at JBR between 2-5Z, 5-8Z at MEM/MKL, and between 7-10Z at TUP. S winds will veer NW with an associated cold front tonight. Post-frontal MVFR ceilings are anticipated late tonight with a return of VFR conditions towards Thursday afternoon. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...Flood Watch through Thursday morning for TNZ003-004-021-022. && $$ PUBLIC FORECAST...DNM AVIATION...CJC
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
645 PM CDT Wed May 8 2024 .KEY MESSAGES... - Scattered, pulse-y thunderstorms expected this afternoon and evening across southern Minnesota. Locally heavy rain and a few strong or severe storms are possible. - Periodic shower and thunderstorm chances will continue through early next week. - Temperatures will remain near or above normal. && .DISCUSSION... Issued at 252 PM CDT Wed May 8 2024 Our stagnant mid/upper level low pattern will slide east tonight, setting up a nearly horizontal, positively-tilted trough axis along the Minnesota/Iowa/SoDak border region. Soundings show an inverted-V setup, with cold air above a warm and dry boundary layer. Surface temps have already eclipsed 70F in much of southern Minnesota, supporting a broad area of 500 J/kg SBCAPE embedded with pockets of 1000+ J/kg along the MN/SoDak border. Steep low-level lapse rates will be enough to create a broad area of showers/storms, however lack of wind shear should prevent any longer-lived supercell convection. In other words, we are expected storms to form and dissipate quickly, leading to isolated hail and strong downdraft winds. Given the slow movement of the occluded low, some storms could tap into the effective SRH and form brief landspouts or weak non-supercell tornadoes. The main threat will shift to locally heavy rains overnight, with the highest totals expected south of the MN/IA border. Northeasterly flow behind the occluded front will advect in slightly cooler and drier air, leading to quiet weather tomorrow afternoon/night. An upper-level shortwave disturbance will then slide southeast through the Great Lakes region on Friday. Steeper lapse rates and patches of weak MUCAPE will likely lead to a broad area of scattered showers and thunderstorms across east-central Minnesota and western Wisconsin. The main forcing, and greatest QPF, looks to be trending slightly further east into Wisconsin per model (Euro and GFS) run-to-run change. The upper-level pattern will stay largely the same through early next week, with a cut-off low to the west and general troughiness to the east. Any small scale disturbances that ride down from Canada would bring similar chances for scattered showers and thunderstorms over the Upper Midwest. Temperatures will trend 5-10 degrees above normal, with some areas potentially seeing highs in the 80s Sunday- Tuesday. The best chance for that comes on Sunday, with nearly 50% of NBM members breaking the 80F mark across the southern half of Minnesota. The cut-off low over the western CONUS will attempt to progress eastward by mid-week, which would likely be the general timeframe of our next shot of active weather. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 623 PM CDT Wed May 8 2024 Rain this afternoon has been tied to an upper low over eastern SoDak and an inverted surface trough up along the MN/SD border. These features will slowly sag south and east through the night, which means precipitation is in all likelihood done for MPX terminals, so removed precip mention from all TAFs. Thursday morning, as the surface low moves across Iowa, numerous models show MVFR cigs developing to the north of the low that could swipe MSP, MKT, & RWF. Those MVFR cigs could come with a few sprinkles, but moisture on forecast soundings is pretty shallow, so little in the way of rainfall is expected. After the morning MVFR threat, skies will clear out through Thursday afternoon with 10-20 kt NNE winds. KMSP...The HRRR continues to hint at a shower threat between 12z and 16z Thursday morning, though RAP forecast soundings show rather shallow moisture being in place during the morning, which should really limit the shower threat. /OUTLOOK FOR KMSP/ FRI...Mainly VFR. Chance PM MVFR/-TSRA. Wind NW 20G35 kts. SAT...VFR. Wind NW 10-15G20 kts. SUN...VFR. Wind WSW 10-15G20 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...BED AVIATION...MPG
Area Forecast Discussion
National Weather Service Marquette MI
326 PM EDT Wed May 8 2024 .KEY MESSAGES... - Multiple passing low pressure systems will keep rain chances in the forecast into early next week. && .SHORT TERM /THROUGH TONIGHT/... Issued at 325 PM EDT Wed May 8 2024 Water vapor imagery and RAP analysis show a broad mid-level low centered over SD and troffing over se Canada back into the Great Lakes. Into the latter trof, a shortwave is dropping toward Lake Superior. Btwn the mid-level low and the eastern trof, a col is over ne MN/NW WI. In the wake of the shortwave that brought rain to the area last night, particularly the e half of Upper MI, it`s been a dry aftn so far, but daytime heating has led to cu/stratocu development inland from the stabilizing influence of Lake Superior. Recent radar imagery indicates that these clouds are now building enough depth for some sprinkles or a few -shra in eastern Gogebic County. Temps currently range from the 40s near Lake Superior to the mid 60s F in the interior closer to the MI/WI stateline. Approaching shortwave from the n and weak diurnal instability will support some -shra/sprinkles over portions of interior western Upper MI near the MI/WI stateline for the next several hrs. Not out of the question that a few sprinkles could develop over the eastern fcst area as well given the buildup of clouds in that area. A dry night will then follow with skies becoming partly cloudy. 850mb thermal trof is currently supporting considerable stratocu ne of Lake Superior. As this thermal trof advects sw, stratocu will also advance sw. Some of this cloudiness may appear in Upper MI around sunrise, but probably more so during Thu morning. Expect low temps tonight in the mid 30s to lwr 40s F. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Issued at 248 PM EDT Wed May 8 2024 Upper air pattern consists of a 500 mb trough extending from New England down to the central Rockies 12z Thu. There is also a shortwave in northern Saskatchewan 12z Thu which heads down to Lake Winnipeg 00z Fri and into the upper Great Lakes on Fri. Dry and quiet weather lasts into Fri afternoon. Di no make too many changes to the going forecast overall. In the extended, the GFS and ECMWF show a 500 mb trough in the ern U.S. and a trough in the central Rockies and ridge on the west coast 12z Sun. There is also a shortwave in south central Canada 12z Sun that moves into the upper Great Lakes Sun night. A shortwave moves into the northern Rockies 12z Tue and into the northern plains 12z Wed. Temperatures will continue to be above normal for this forecast period and will be unsettled with weak systems moving through the area with one on Sunday and one on Wednesday with a sfc front hanging around the area as well according to the manual sfc progs. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 150 PM EDT Wed May 8 2024 Lower level moisture is mixing out and is being lifted by building mixed layer. Advection of stabilizing marine layer off of Lake Superior will also work to limit any cu/stratocu development closer to the lake this aftn. For IWD/CMX, this stabilizing influence will allow VFR to prevail this aftn, and VFR will continue tonight. At SAW, expect stabilizing flow off of Lake Superior to result in MVFR cigs scattering out to VFR in the next hr or two. VFR will then continue at SAW tonight. Area of lower level moisture represented by the stratocu per vis satellite imagery well ne of Lake Superior will advect sw today and tonight. While some of this moisture will mix out this aftn, it should contribute to cu/stratocu/MVFR cigs developing at all terminals after sunrise on Thu. After a few hrs or so, cloud bases will lift to VFR, or the clouds will scatter out to VFR. && .MARINE... Issued at 248 PM EDT Wed May 8 2024 Northeast winds of 15 to 25 knots will prevail through tonight mainly over western and central portions of Lake Superior. After that, despite wind shifts due to multiple low pressure systems, winds will remain below 20 knots through Monday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Small Craft Advisory until 10 PM EDT /9 PM CDT/ this evening for LSZ240>242. Small Craft Advisory until 6 PM EDT this evening for LSZ243- 244. Lake Michigan... None. && $$ SHORT TERM...Rolfson LONG TERM...07 AVIATION...Rolfson MARINE...07
Area Forecast Discussion
National Weather Service Morristown TN
1141 PM EDT Wed May 8 2024 ...New UPDATE... .UPDATE... Issued at 1135 PM EDT Wed May 8 2024 Updated forecast package with new Tornado Watch #214 issued for southeast Tennessee and southwest North Carolina to go until 4 AM EDT with plateau and central valley counties in Tornado Watch #211 expiring at midnight EDT. Several supercell storms that moved into the plateau counties and southeast Tennessee a few hours ago have formed into a line and have produced heavy rainfall across the eastern part of the region. Expect high coverage of showers and thunderstorms for the rest of the night with a risk for more severe storms in the southern third and heavy rainfall elsewhere. Later tonight HRR model shows a fast moving line of storms to move from the plateau to North Carolina by around 900 AM. This may pose a high wind threat and also more flooding with the heavy rain this evening. && .UPDATE... Issued at 745 PM EDT Wed May 8 2024 Updated rain chances this evening with low chances before large area of showers and storms get here later this evening. Still looks like strong storms with threat for damaging winds and large hail and isolated tornadoes southwest half of the area. Also heavy rainfall with flash flooding still possible with saturated soil from rainfall earlier this morning and afternoon. Updated forecast sent. && .SHORT TERM... (This evening through Thursday) Issued at 324 PM EDT Wed May 8 2024 Key Message: 1. Risk of severe weather remains through this evening and into the overnight hours. All hazards remain possible, large hail, heavy rain, flooding, damaging winds, tornados. 2. The highest risk areas from now through this evening will generally be along I-40, from Knoxville and westward, including the northern Cumberland Plateau. Then, the severe threat shifts further south, south of I-40, later this evening into tonight. Discussion. Scattered showers and a few storms are currently ongoing across the forecast area. This mornings round of showers and storms have significantly stabilized the atmosphere, generally from Morristown and all points northeastward into northeast TN and southwest VA. These areas are still in a slight risk for severe weather but no longer under an enhanced risk. These are the areas that we feel will be the least favorable to see additional severe weather through the rest of the event. Having said that, do not let your guard down but just keep in mind the threat probabilities are now lower. With skies just now beginning to clear, if instability can recover across these areas then the threat levels will rise. From now through late evening, the area of greatest concern will be along the I-40 corridor from Knoxville and points westward, as well as across the northern Cumberland Plateau. There is currently a tight instability gradient across middle TN and east along I-40 into the east TN Valley. Latest HRRR shows additional convection developing over the next few hours across middle TN and then progressing east along the instability gradient. All hazards will be possible with this next round of convection. The biggest question is how far north will the threat area be. Current sat imagery shows skies clearing across northern Cumberland Plateau. HRRR shows this area having modest instability recovery through this evening. The general timeframe for this next round appears to be between 22Z and 03Z. HRRR also continues to show a few strong helicity tracks across this area, which is more reason for concern. Thereafter, a line of convection moves in south of I-40 corridor between 02 and 03Z and progresses east across the southern east TN valley and into southwest NC through 06Z. All hazards remain possible with this line of convection as well. The final round of convection looks like it will push through the area between 06Z and 12Z. The severe threat during this last round is much more uncertain due to limited instability. The biggest threat area, if any, should be limited to the southern TN Valley as this area has the best chance to have some remaining instabilty according the HRRR. All hazards remain possible with this final line of convection but much more uncertainty exists. One area we have not thoroughly discussed is the flooding. Thus far, we have seen several areas receive between 1 and 2" of precip with isolated pockets of 2 to 3". With the next few rounds of convection, we are expecting an additional 1 to 2" with isolated amounts of 2 to 3". These additional rainfall amounts will become increasing problematic across areas that have already seen the higher rainfall totals. 6 hour FFG is generally 1 to 2 inches across the areas that have received the higher totals. There are a few isolated areas with FFG as low as low as 0.5" in 6 hours. Showers and storms should generally exit the forecast area tomorrow morning between 12 and 15z. A few showers and isolated storms may linger through mid afternoon across southwest NC. Dry conditions are forecast areawide by late afternoon with sunshine returning to most areas. && .LONG TERM... (Thursday night through next Wednesday) Issued at 324 PM EDT Wed May 8 2024 Key Message: 1. Cooler weather late week and into the weekend behind the cold front. 2. Lingering showers possible Friday with shortwaves within the northwest upper flow. Quick shortwave may bring some showers and thunderstorms Saturday (highest chance northern areas). 3. Drier weather expected Sunday and Monday with a gradual warming trend. Chance of showers increases again mid-week. Discussion. Behind the cold front on Thursday, cooler and drier air will arrive across the region within the northwest upper flow. Troughing and cooler air aloft will result in some diurnal convection on Friday afternoon with limited potential for thunder. A stronger shortwave is expected to move through the upper level northwest flow on Saturday with scattered showers and thunderstorms possible on Saturday afternoon, with the highest chance for precipitation across our northern counties through southwest Virginia. Ridging begins to build on Sunday and Monday with drier weather and a gradual warming trend into early next week. Chance of rain begin to return on Tuesday and Wednesday as a system is expected to develop across the Lower Mississippi Valley, but certainty in timing && .AVIATION... (00Z TAFS) Issued at 745 PM EDT Wed May 8 2024 More rounds of showers and thunderstorms to move across the area overnight tonight. Mostly MVFR conditions anticipated late tonight and early Thursday morning but there will be a few hours of VFR conditions before storms move in this evening. Any thunderstorms passing over a terminal could produce gusty and erratic winds that differ from the official TAF forecast. Expect improving conditions by early afternoon Thursday from north to south as rain moves out. Gusty southwest winds tonight and then west to southwest and gusty Thursday afternoon. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 68 86 62 76 / 90 60 30 20 Knoxville McGhee Tyson Airport, TN 66 81 59 70 / 90 70 30 30 Oak Ridge, TN 65 83 58 71 / 90 70 20 30 Tri Cities Airport, TN 63 77 57 67 / 90 80 30 40 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...Flood Watch until 8 AM EDT Thursday for Cherokee-Clay. TN...Flood Watch until 8 AM EDT /7 AM CDT/ Thursday for Anderson- Bledsoe-Blount Smoky Mountains-Bradley-Campbell-Claiborne- Cocke Smoky Mountains-East Polk-Grainger-Hamblen-Hamilton- Hancock-Hawkins-Jefferson-Johnson-Knox-Loudon-Marion-McMinn- Meigs-Morgan-North Sevier-Northwest Blount-Northwest Carter- Northwest Cocke-Northwest Greene-Northwest Monroe-Rhea- Roane-Scott TN-Sequatchie-Sevier Smoky Mountains-Southeast Carter-Southeast Greene-Southeast Monroe-Sullivan-Unicoi- Union-Washington TN-West Polk. VA...Flood Watch until 8 AM EDT Thursday for Lee-Russell-Scott VA- Washington VA-Wise. && $$ SHORT TERM...TD AVIATION...TD
Area Forecast Discussion
National Weather Service Nashville TN
635 PM CDT Wed May 8 2024 ...New AVIATION... .SHORT TERM... (Rest of today through Friday) Issued at 1152 AM CDT Wed May 8 2024 Earlier warm front now stationary and centered w-e just north of I- 40. This far northern area has served as the flood threat with numerous advisories and warnings issued thus far. Flood reports have been received mainly across the Robertson and Sumner county areas. Energy along the boundary is working eastward with the bulk of the activity now across the Plateau. To the south, airmass is hanging on to a weak cap despite warming temps. Upstream however, 2 separate slugs of energy will be pushing southeastward. This translates to 2 rounds of severe. The 1st will occur from 3pm to 6pm, with the 2nd round in the 8 pm to midnight timeframe. All forms of severe weather will be possible. Instabilities will be greatest across our south so I would think the largest(non tornadic) hail would occur there. As for rainfall amounts, the flood watch shall continue. Latest Hrrr shows isolated storm totals of up to 6 inches across an area stretching from far north central middle TN eastward across the northern Plateau. Now models do hang onto the light to moderate shower activity through 12Z to 18Z before ending. Look for clearing skies Thursday night with cooler temps. Upper troughing will feature a Friday shortwave with a few showers. Saturday looks similar with an additional shortwave. The near term temps will continue to run rather warm tonight and Thursday with 80s for highs once again. Noticeably cooler by Friday morning with lows back down into the 50s. We may seven see some 40s by Saturday morning. && .LONG TERM... (Friday Night through next Wednesday) Issued at 1152 AM CDT Wed May 8 2024 In the extended forecast, ridging will return for Monday. The next system of interest will be for Tuesday and Wednesday of next week. Instability looks weak for now so mostly just looking at showers and non severe tstms for now. Extended temps will start out on the cool side but will warm back to near 80 for highs by mid week. Overnight lows will work back into the lower 60s as well. && .AVIATION... (00Z TAFS) Issued at 628 PM CDT Wed May 8 2024 Widespread thunderstorms will continue across the area through 09z. IFR/LIFR conditions in thunderstorms due low cigs, low vis, heavy rain, and gusty winds. A line of thunderstorms will move in to the northwest after 04z and will work south and east through 09z. Gusty winds will be possible along with that line along with the heavy rain. VFR conditions should build in behind the line but light rain will linger through the night. Rain moves out after 12z. Southerly winds up to 10 knots shifting westerly behind the line of thunderstorms, higher winds possible in any thunderstorms. && .PRELIMINARY POINT TEMPS/POPS... Nashville 68 86 58 72 / 90 30 10 10 Clarksville 66 83 54 70 / 80 10 10 10 Crossville 63 79 53 66 / 90 50 20 30 Columbia 66 85 56 72 / 100 30 10 10 Cookeville 65 80 54 67 / 90 50 20 20 Jamestown 63 79 53 66 / 90 50 20 30 Lawrenceburg 66 84 57 72 / 100 40 10 10 Murfreesboro 66 85 55 72 / 100 40 10 10 Waverly 66 83 54 71 / 90 10 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... Flood Watch through Thursday morning for Bedford-Cannon-Cheatham- Clay-Coffee-Cumberland-Davidson-De Kalb-Dickson-Fentress-Grundy- Hickman-Houston-Humphreys-Jackson-Lewis-Macon-Marshall-Maury- Montgomery-Overton-Perry-Pickett-Putnam-Robertson-Rutherford- Smith-Stewart-Sumner-Trousdale-Van Buren-Warren-White-Williamson- Wilson. && $$ SHORT TERM...21 LONG TERM....21 AVIATION.....Mueller
Area Forecast Discussion
National Weather Service Pueblo CO
650 PM MDT Wed May 8 2024 .KEY MESSAGES... - Cooler and wetter weather appearing likely Thursday into the weekend. - Accumulating snow across the higher terrain is also appearing likely, with the highest snowfall amounts and impacts expected across the peaks. && .UPDATE... Issued at 648 PM MDT Wed May 8 2024 Red Flag Warning has been allowed to expire this evening as winds start to ease and humidity levels gradually improve. Incorporated lates obs and satellite data, as well as hi-res HRRR and RUC guidance. Moore && .SHORT TERM /THROUGH THURSDAY/... Issued at 327 PM MDT Wed May 8 2024 Overall, relatively quiet across southern this afternoon with partly cloudy to mostly sunny conditions in place for most areas. West northwest flow situated across the central mountains is assisting with some expansive cloud cover this afternoon, though lacking deeper moisture has limited any snow development. This will continue to be the case for the remainder of the afternoon into the evening, especially as the upper trough sags to the south and flow becomes more baggy. Surface trough situated across southeast plains is supporting some spotty stronger winds/gusts this afternoon and along with some lower RH values, am still seeing at least spotty critical fire weather conditions. Given these conditions in place and the higher likelihood for them to continue over the next couple of hours, have opted to leave the Red Flag Warning in effect. As the upper trough sags south later this evening into tonight, will see a cold front move south through much of the Colorado. Initially, no real impacts look to occur. However, increases in moisture along veering flow will support a return to moist/upslope flow and increases in isentropic ascent will support expanding cloud cover and increases in precip. Precip chances will really increase Thursday morning into the afternoon time frame and initially for areas over and near the mountains. During the day on Thursday, snow will be likely across the mountains and with rain expected over the lower elevations. Amounts and impacts from the snow across the mountains do look to be low through Thursday afternoon, and have not issued any winter headlines at this time. With some weak instability expected to be in place, can`t rule out some rumbles of thunder over the higher terrain. By late in the period, will begin to see the precip really blossom, as the upper trough/low continues to draw near. In this cloud cover and precip, temps are expected to be well below average on Thursday. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... Issued at 327 PM MDT Wed May 8 2024 Recent trends with guidance today is suggesting that portions of south central Colorado, especially over and near the higher terrain, could see a period of steady light to at time moderate precip from Thursday night into Friday. With the upper low to the west, will see deep southerly flow situated across southern Colorado. Increases in large scale ascent, deep moist/upslope flow, and continued isentropic ascent look to really focus precip development into our area during this time. Have increased pops, qpf, and snow to account for these trends. Rainfall rates don`t look to be overly concerning at this time given lower instability, even with any thunderstorm development. Most locations across south central Colorado will likely see this rain result in amounts of one half inch to around an inch. For the higher terrain, highest snowfall amounts look to be primarily for the higher peaks of the mountains and with this expectation, think impacts will be low. That being said, am getting a little concerned that snow levels could lower more than currently forecast and if so, amounts and impacts could be higher. This will definitely need to be monitored, along with the need for winter headlines. Should see a trend for additional precip development to focus more across the higher terrain, especially the Continental Divide, later Friday into Friday night. This will be in response to this upper low moving more to the south. For the remainder of the weekend into early next week, should see this upper low slowly shift to the east with precip chances likely returning. Coverage of precip looks to be lower, and once again, likely focused over the higher terrain. The risk of any strong to severe storms does look to be low at this time, however, increases in moisture and instability could support a higher risk on Saturday, especially as this system moves through. A trend towards more normal temps is expected into early next week, along with periodic precip chances. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 528 PM MDT Wed May 8 2024 KALS: Mostly VFR through 24 hours. Winds will pick up by 12Z tomorrow, remaining southeasterly through the end of the period with mid to low-level clouds, bordering on MVFR. Showers will move in from the adjacent higher terrain tomorrow afternoon, and cloud ceilings will fall as showers approach the terminal. KCOS: Winds will remain northwesterly for a few hours before turning more northerly overnight. Clouds will increase and ceilings will lower to near-MVFR by 12Z. Showers are expected in the area tomorrow after 16Z or so, and will lower conditions to MVFR. Rain showers will be possible at the terminal and could lower visibility. KPUB: East-northeasterly winds overnight will turn more northerly prior to 12Z. Clouds will remain VFR but will increase in coverage through around 16Z. Showers are expected in the area tomorrow and may drift close to the terminal. Confidence in precipitation directly overhead is still too low to include in the 00Z TAFs, but clouds will sink to MVFR heights tomorrow afternoon. && .PUB WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...MOORE SHORT TERM...RODRIGUEZ LONG TERM...EHR/RODRIGUEZ AVIATION...GARBEROGLIO
Area Forecast Discussion
National Weather Service Shreveport LA
1008 PM CDT Wed May 8 2024 ...New UPDATE, SHORT TERM... .UPDATE... Issued at 1001 PM CDT Wed May 8 2024 Expanded Tornado Watch 210 in time to midnight and included some Arkansas counties for a while longer too active SVR warnings. && .UPDATE... Issued at 923 PM CDT Wed May 8 2024 Primarily to warm overnight lows at this time. && .SHORT TERM... (Tonight through Friday Night) Issued at 1001 PM CDT Wed May 8 2024 The HRRR has been wrong before, so we will give these storms a couple more hours of breathing room along our I-30 corridor with the Tornado Watch editing so to speak. Lots of CAPE and momentum now with radar trying to play connect the dots on these towers. We have kept some maybe severe wording in for the overnight at this time. More to come by midnight and of course and in our new zone package for the day ahead with our broad I-20 corridor Enhanced Risk for day 2. /24/ && .LONG TERM... (Friday through next Tuesday) Issued at 339 PM CDT Wed May 8 2024 Quieter weather briefly returns through the weekend before precipitation chances are reintroduced early next week. Quasi- zonal flow aloft will allow for a mid-level trough to drift eastward across the Four Corners into the Southern Plains. This trough, in combination with ridging shifting further east across the Mississippi River, will maintain enhanced southerly flow and moisture through most of early next week. Precipitation chances will remain through the same time period as a result. /16/ && .AVIATION... (00Z TAFS) Issued at 635 PM CDT Wed May 8 2024 Widespread haze originating from Mexico and Central America will result in some instances of MVFR visibilities at the start of the period. A complex of strong to severe convection is expected to enter portions of Southeast Oklahoma and Northeast Texas around 09/02z before moving southeast affecting most TAF sites. The storms should begin to rapidly weaken after midnight local time, so convection was not mentioned at KMLU or KLFK. Low clouds are expected to rapidly develop after the storms dissipate resulting in widespread IFR/LIFR flight conditions. A slow improvement is expected after daybreak Thursday, but VFR conditions should return to most sites by 09/18z. More strong to severe thunderstorms are anticipated to affect Southeast Oklahoma and East Texas, potentially affecting KTYR, near the end of this TAF cycle. CN && .PRELIMINARY POINT TEMPS/POPS... SHV 75 90 67 83 / 40 30 50 0 MLU 75 90 65 81 / 30 20 60 0 DEQ 66 86 58 80 / 60 30 30 0 TXK 72 87 62 81 / 70 30 40 0 ELD 72 86 61 80 / 60 20 40 0 TYR 72 88 65 82 / 40 40 40 0 GGG 74 88 65 82 / 40 30 50 0 LFK 74 92 67 84 / 10 30 40 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...24 LONG TERM....16 AVIATION...09
Area Forecast Discussion
National Weather Service Tallahassee FL
1002 PM EDT Wed May 8 2024 ...New UPDATE, MARINE... .UPDATE... Issued at 950 PM EDT Wed May 8 2024 On the forecast update, have added patchy fog to our Big Bend and south-central GA counties late tonight and around sunrise. The dewpoint of 78F at Buoy 42036 suggests a favorable environment for fog as the moister air moves northeast overnight. Otherwise, the latest HRRR runs are speeding up the timing with the first round of storms coming in from the north tomorrow afternoon. && .NEAR TERM... (Through Thursday) Issued at 344 PM EDT Wed May 8 2024 The gusty winds will calm down this evening and the overnight hours. Temperatures tonight will fall to the low 70s. More clouds will filter in during the overnight hours. Patchy fog may be possible but not expected to be widespread as it has been for the past couple of mornings. For Thursday: The upper level ridge over the Gulf will flatten through the day as mid-level perturbations traverse east over Alabama and Georgia ahead of a strong cold front. Our northernmost counties will likely see thunderstorms during the afternoon hours on Thursday. Thursday afternoon and evening is expected to be quite active as the environment will be favorable for severe weather. Instability will be elevated with CAPE ranging between 1000-2000 J/kg and deep-layer shear around 35-45 kts and steep lapse rates. These parameters will be conducive to strong to destructive wind gusts (up to 75 mph), large hail, and a few tornadoes. The storm mode looks to approach the region as a squall line moving south through the afternoon hours and evening hours. Because of these threats, the SPC has upgraded the risk for our northern AL and GA counties (Tifton, GA to Enterprise, AL) to an Enhanced (3 of 5) risk for severe weather Thursday afternoon through the night. From that line down to I-10, these areas are included in a Slight (2 of 5) risk for severe weather. The threats are the same, but the amount of coverage for this area is less from numerous storms to scattered storms. South of I-10 to the coast is in a Marginal (1 of 5) risk for severe storms. There is also a heavy rain threat for our northwest counties, hence the WPC highlighted the area in a Marginal (1 of 4) risk for excessive rainfall. The Enterprise, AL to Dawson, GA line has a forecast PWAT greater than 1.75". The northern most part along that line is clipped into a Slight (2 of 4) risk for excessive rainfall. PoPs for Thursday afternoon range from 30-60 percent for areas north of I-10. South of I-10 has about a 20% chance for showers and thunderstorms. Timing of storms: We expect an overall three rounds of storms for Thursday afternoon, the second round happening Thursday night into Friday, and the third happening around daybreak Friday. Round 1 storm timing will begin around 12pm ET for our northern counties in AL and GA, moving south during the afternoon through the evening. Round 2 will have the greatest risk for severe storms, which will be discussed in the short term. Not everyone will see showers and thunderstorms on Thursday, so temperatures are still expected to rise to the low 90s, as storms are not expected until the late afternoon. Heat indices for areas around the I-75/I-10 corridor will be in the upper 90s. && .SHORT TERM... (Thursday night through Friday night) Issued at 344 PM EDT Wed May 8 2024 The main story will be the potential for severe weather. The D2 forecast from SPC added an Enhanced Risk for severe weather from about Berrien Co GA to Coffee Co AL northwards, south of that line, a Slight Risk of severe weather to about I-10, with a marginal risk dipping down into the the coastal counties and most the FL Big Bend. The situation is a one-two punch for severe weather. The first round could be an MCS dropping into SW GA from the north which is talked about in the near term. Then we have the main event Thu night into Friday where we could have a squall line come through. This is expected to be the larger event where we could see numerous severe storms capable of producing damaging and potentially destructive winds, large hail, and even embedded tornadoes. There is the potential for a third event / squall line Friday afternoon which will be dependent on boundaries and prior convective systems. && .LONG TERM... (Saturday through Tuesday) Issued at 344 PM EDT Wed May 8 2024 We will be post frontal by Saturday with high pressure building in for the weekend. Northerly winds will usher in cooler air to the region, placing highs in the upper 70s and low 80s for the GA and AL counties, and in the low to mid 80s in FL. The reprieve in temperatures will continue overnight with lows falling into the mid to upper 50s for most of the region. Warming returns on Sunday with highs in the low to mid 80s. By early next week the pattern looks to change and become wet again. Another shortwave looks to move across the northern Gulf states with our region possibly being impacted on Tuesday as winds turn to being southeasterly. With this shortwave possibly moving overhead, a stationary boundary to our south, left behind from the previous system, and a low-level wind field again around 30-45 kts, the potential for severe is once again present as well as the threat for heavy rain. We`ll have to see how this progresses over the next few days to have better confidence, be sure to come back for updates. && .AVIATION... (00Z TAFS) Issued at 745 PM EDT Wed May 8 2024 Similar to the last few evening, stratocumulus clouds with bases of 010-015 are gathering along the Panhandle coast. They will move and spread inland after sunset, bringing IFR cigs and reduced vsbys as we move through the night and get out to sunrise. Clouds will lift and scatter during the hours after sunrise. On Thursday afternoon, a large cluster of thunderstorms will move southeast through eastern Alabama and Georgia, possibly slipping south of the Florida state line while weakening late in the valid period. && .MARINE... Issued at 950 PM EDT Wed May 8 2024 An Atlantic ridge axis across the southern Florida Peninsula will retreat southward on Thursday. A cold front will slowly approach from the north on Friday, preceded by strong to severe thunderstorms over the waters. The front will limp across the waters on Friday night. It will be followed by moderate to occasionally fresh northerly breezes on Saturday morning. Surface high pressure over the southern Plains on Saturday will move across the Southeast States on Sunday, causing winds to clock around. High pressure will move east into the Atlantic on Monday, and low pressure will deepen over the Southern Plains. && .FIRE WEATHER... Issued at 344 PM EDT Wed May 8 2024 Wetting rains and severe storms are expected for our northern GA districts Thursday afternoon through Friday. All regions are expected to receive a wetting rain from early Friday through the afternoon. Along with the rain; gusty, damaging winds are expected in thunderstorms, with large hail, and possible tornadoes. Outside of rain and thunderstorms, high dispersions are expected for Thursday afternoon for areas south and east of the storms. So, along the I-75 corridor will have dispersion indices around 75 units. Mixing heights will be around 4000 feet. The cold front will pass through during the day on Friday, shifting the winds northerly by Friday night. Dispersions will increase to about 60-70 units with the front on Friday afternoon for our northwestern most counties. Elevated dispersions are expected for Saturday afternoon with northerly winds and dry conditions. The MinRH for Saturday will be around 35-40%. && .HYDROLOGY... Issued at 344 PM EDT Wed May 8 2024 The forecast generally remains on track with a Slight Risk clipping our extreme northern counties in AL and GA for Excessive Rainfall with a Marginal Risk extending from Ben Hill Co in GA to Geneva Co in AL. For Friday, the Marginal Risk is expanded south clipping most of the CWA. Moisture looks to be bountiful with PWATs around 2 inches or so. The main concern looks to be with flash flooding if storms move slowly or train. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 73 93 72 85 / 10 20 30 80 Panama City 75 86 73 83 / 20 20 30 70 Dothan 73 90 70 83 / 10 50 50 80 Albany 72 92 69 84 / 10 50 50 80 Valdosta 71 92 72 85 / 10 30 40 90 Cross City 69 87 71 85 / 0 10 20 80 Apalachicola 75 83 73 82 / 10 10 20 60 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk until 8 AM EDT /7 AM CDT/ Thursday for FLZ108-112-114-115. GA...None. AL...None. GM...None. && $$ NEAR TERM...Montgomery SHORT TERM...KR LONG TERM....KR AVIATION...Haner MARINE...Haner FIRE WEATHER...Montgomery HYDROLOGY...Haner