Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/15/23


Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
918 PM CST Tue Feb 14 2023 .UPDATE... Issued at 907 PM CST Tue Feb 14 2023 Forecast is generally in good shape for the overnight hours, although a few questions linger. We`ve seen snow the past several hours across the eastern CWA, with lowered visibility. Already seeing road closures and no travel advised over parts of the east. Also watching the second wave of energy to the west, now moving into the western CWA. Snow has persisted there, with some reduction in visibility as well. One question is determining just how far east this area of snow continues and how impactful will it be to visibility given the very strong winds currently in place. Starting to see snow fill in across the James valley recently, which the HRRR has been showing nicely the past several runs. Feel headlines are good for the time being, but another question revolves around how impactful any snow/blowing snow will be west of Brown/Spink, which is largely dependent on the longevity/persistence of the western wave of snow as it moves east. If this turns out to wane in intensity over the next several hours, perhaps headlines may not be needed over central SD up to Brown/Spink counties. Will continue to monitor trends. && .SHORT TERM...(This Evening through Wednesday Night) Issued at 309 PM CST Tue Feb 14 2023 The main challenge in the short term is the low/medium confidence in overall snowfall totals due to ongoing model discrepancies. Starting off synoptic-wise. ECMWF Ens/GEFS ensembles agree on the position and intensity of the 500mb low which at 00Z Wednesday is over NE/IA border and a trough/sfc low moving in from the west. These two systems will merge pretty much over our CWA late this afternoon and into this evening moistening up the layers, seen in Bufkit. By 06Z this low will be centered over MN/WI border in which most of the James River Valley and eastern CWA will be on the western/northwest side of this low/baroclinic zone. By 12Z Wednesday, the closed low opens up to a wave that will continue to push east. At 850mb, WAA winds out of the southwest will then shift as the 850mb low will be over much of the CWA by 00Z per deterministic models (which are in agreement for this). We start getting steep pressure rises behind the low starting around 00Z Wed (+1 to +5in a 3 hour period.) This, along with CAA becoming dominant, steep pressure gradients behind the low and high to our west, we really see these CAA winds ramps up! The deterministic models indicate winds at 850mb increasing to 40-50+kts over western and central CWA by 00Z Wed. As this low moves east/northeast, the stronger winds behind the low will also move east over the James River valley and eastern CWA. The highest gusts will be over the Prairie Coteau between 00-06Z Wednesday with 850mb/surface wind gust up to 50kts. Between 12-18Z Wednesday, the strongest winds will continue to push east/northeast with winds over the Coteau still 30-50kts at this time then decreasing. By Wednesday evening, a high pressure system will move in from the west and decreasing these winds. With this setup, CAMs+HREF continue to show WAA precipitation in the form of rain, and in pretty good agreement on timing, moving in from the south affecting more of the eastern/southeastern CWA with several RAP bufkit soundings suggesting this precip as temps remain above freezing. Newer runs have kept this rain around a little longer before we start seeing a mix. As temps drop tonight, precip will switch to a rain/snow mix before changing all over into snow. However a few soundings across central/south central SD do suggest we could see a short window of time for some freezing drizzle to mix in between ~00-02Z. CAMs show a switch over to all snow by 04Z or so over the central and eastern CWA with snow exiting the area by ~12Z Wednesday. With the lighter snow expected in central and western CWA, QPF totals are 0.10 of an inch or less with prob over 0.10 only around 10-30% in this area per EC. This overall trend is backed up pretty well by both ECMWF/GEFS total precipitation through 12Z Wednesday. However for the James River Vally to our eastern CWA, there is a little bit of a difference. ECMWF has more QPF spread further west (just near the Missouri River) where GEFS keeps it more over the James River Valley and east. The heavier amounts of QPF do agree to be more eastern and southeastern CWA with prob of over 0.50 of an inch at 50-60% in this area per EC ens) but this time, GEFS wants to take those higher QPF further west than EC. So overall QPF will range to up to 0.68 over Deuel and surrounding counties to about 0.06 over Corson County and surrounding. The probability of snowfall amount over 1 inch for both EC ens/GEFS show 10% or less, west of the Missouri River. Prob of 3 inches or over really varies between EC and GEFS. EC has brought the % down over the James River Valley ranging from 10-30% and a little higher in the Prairie Coteau (up to 40%) However GEFS shows up to 60% for over 3 inches. Prob of 6 inches is only shows by GEFS over the Coteau with probs 10-20%. WPC prob of 4 inches or more is 40% over the James River Valley and up to 70% near Sisseton Hills and 6 inches or over 20-30%. This is why there is such a large range in snowfall amounts. Bufkit soundings show neg omega within the DGZ zone and starting out with lower snow ratio with the rain/snow mix then they will increase as CAA becomes more dominant behind the front per RAP soundings. Also, during the precip, any earlier changeover to snow or vice versa will have an effect on the total snowfall amounts as well as changes in path of the low. So the combination of snow and gusty winds will create blowing snow, leading to low visibilities in and around the Coteau/Sisseton Hills, thus the Blizzard Warning remains and goes into effect this evening. Counties west of this have an advisory. We will need to watch these areas closely during the snowfall and adjust headlines as needed and if more snow falls over Brown/Spink county along with these winds, they may need to be added in the blizzard warning due to blowing snow as eastern Brown and Spink counties is showing higher snowfall than western side of the counties. So confidence is 50/50, so left it as a WW with blizzard conditions possible. .LONG TERM...(Thursday through Tuesday) Issued at 309 PM CST Tue Feb 14 2023 The main forecast challenge in the extended period will be precipitation chances late in the period. An upper level trough will be over the central part of the country to start the period, and looks to exit the area Thursday night, with northwest flow setting up on Friday. As another trough approaches and looks to skirt just to the north, a more zonal flow develops Friday night and remains in place through Sunday morning. A weak trough will track through Sunday night, with another moving through on Tuesday. At the surface, high pressure will be the dominant feature over the region on Thursday, then gets pushed east by an approaching low pressure system. The front associated with the low will track across the CWA Friday afternoon/evening, with weak high pressure behind it quickly getting pushed east Friday night/Saturday morning as another low approaches. The low will track across South Dakota, putting the best chance for precipitation with it north of the CWA on Sunday. After this, there is quite a bit of discrepancy in the models with the timing and track of a system moving through and possibly bringing some precipitation to the area, and will stick with some small POPs for Monday night and Tuesday for now. High temperatures will range from around 10 degrees across west central Minnesota, to the lower 30s across south central South Dakota on Thursday, from the mid 20s across the Sisseton Hills region to the lower 50s across south central South Dakota on Friday, from the lower 30s northeast to the mid 40s southwest on Saturday and Sunday, from the lower 20s northeast to the upper 30s southwest on Monday, and from the mid teens northeast to the upper 20s southwest on Tuesday. Overnight lows will range from the single digits below zero east to the lower teens west Thursday night, from the lower teens east to the lower 20s west Friday night, from the mid teens east to the mid 20s west Saturday night, from the lower teens east to the mid 20s southwest Sunday night, and from the single digits below zero east to the mid teens southwest Monday night. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 530 PM CST Tue Feb 14 2023 Terminals KABR,KATY,KPIR,KMBG Still seeing areas of FG in the KATY area with VSBY down to 1/4SM. Expecting VSBY to improve a bit once the stronger northerly winds kick in over the next couple hours. Otherwise, a mix of MVFR/IFR CIGs will be across the region overnight as a storm system moves through. Across KABR/KATY, expect -RASN/RASN to develop/expand through the evening and become all -SN/SN by around 02Z. Areas of BLSN through the night as well, especially in the KATY region. Further west across KMBG/KPIR, expect areas of -SN/SN to move into central SD later this evening with reductions in VSBY likely in areas of more persistent snow and BLSN. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...Blizzard Warning until 9 AM CST Wednesday for SDZ007-008-011- 019>023. Winter Weather Advisory until 6 AM CST /5 AM MST/ Wednesday for SDZ003>005-009-010-015>017-033>037-045-048-051. Winter Weather Advisory until 9 AM CST Wednesday for SDZ006-018. MN...Blizzard Warning until 9 AM CST Wednesday for MNZ039-046. && $$ UPDATE...TMT SHORT TERM...MMM LONG TERM...Parkin AVIATION...TMT
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
917 PM CST Tue Feb 14 2023 .UPDATE... Issued at 914 PM CST Tue Feb 14 2023 Precipitation has ended from west central to north central North Dakota, roughly northwest of a line from Dickinson to Belcourt. Several counties were removed from the Winter Weather Advisory for this update, but hazardous travel may continue through the night. It appears the threat for freezing drizzle has mostly diminished across the entire area. The outer band of snow from northeast to south central North Dakota also shows some signs of weakening on radar, but this appearance had presented itself earlier and turned out to be misleading. The more concerning band of snow is beginning to nudge into eastern portions of LaMoure and Dickey Counties, and the visibility at Oakes has just dropped below 1/4 mile. This remains the most likely area for a brief period of blizzard conditions. Winds have begun to diminish across western North Dakota, but remain strong to the east. Sustained speeds in the 30 to 40 mph range are routinely reported, with maximum gusts mostly around 50 mph. UPDATE Issued at 604 PM CST Tue Feb 14 2023 Current observations and trends have dictated significant changes to the forecast. The first problem is that light snow across southwest and central North Dakota has been both much slower to end and much slower to advance eastward than expected. This hasn`t appeared to really add to accumulations much more than was anticipated, but has prolonged reduced visibility due to the combination of snow and wind. The second problem is that widespread freezing drizzle is being observed across north central North Dakota. The freezing drizzle may extend back to the south and west along the western edge of the snow, but north central North Dakota has by far the greatest impacts at this time. RAP moisture profile forecasts show a low level layer of saturation persisting this evening before slowly eroding from west to east overnight. However, the temperature profile of the saturated layer is expected to cool sufficiently for a transition from freezing drizzle to flurries later this evening. The greatest uncertainty in the near term forecast is along and east of a line from Fort Yates to Harvey, excluding the southern James River Valley where a Winter Weather Advisory was already in place. Radar shows the snow to the west of this area is decreasing in intensity as it approaches, which is about the only aspect of the precipitation forecast that has gone as expected. However, HRRR/RAP soundings have also been suggesting freezing drizzle in this area as well due to a lack of ice aloft. Even though this area has yet to experience any winter weather impacts, and some parts may not, we felt that the simplest solution was to transition the Wind Advisory to a Winter Weather Advisory. North central North Dakota was also added to the Winter Weather Advisory, where impacts from freezing drizzle will likely continue for a few hours after it ends. && .SHORT TERM...(This Evening through Wednesday) Issued at 322 PM CST Tue Feb 14 2023 Snow and breezy winds will continue through the evening and overnight from a low pressure system impacting the Central Plains. A strong pressure gradient has set up with cold air advection (CAA) moving in behind a cold front this afternoon. This has produced very breezy winds. The strongest CAA and pressure rises will move through around 04z, this is when the winds will be the strongest, mainly just in the James River Valley, where winds could gust around 50 knots. The NBM had winds close to 60 knots there, but didn`t feel that was reasonable so we used the NBM 10th percentile and capped the wind gusts at 50 knots. A Wind Advisory is in effect until Wednesday morning in the central and south. The band of light snow in western and central North Dakota is very slowly moving east. The CAMs have band breaking up around south central before reforming in the southeast. There is a Winter Weather Advisory already in effect for the southwest where snow has been falling all day, and winds are gusting around 40 knots. The snow forecast of 2-4 inches in the southwest is still on track, however we have received limited reports to validate this. The central will most likely see less than an inch, and the southeast around an inch if the band reforms there. The other Winter Weather Advisory is in the James River Valley starting at 6pm. After Midnight, all the falling snow will have moved off to our east and just the potential of blowing snow will remain through Wednesday morning when the pressure gradient looses and winds relax. The weather will be quiet then, until early next week. .LONG TERM...(Wednesday Night through Tuesday) Issued at 322 PM CST Tue Feb 14 2023 Temperatures will dip mid week to the single digits to 20s for highs through Thursday as the upper level pattern is northern flow, with surface high pressure. Overnight lows will be below zero in the east but not cold enough for a wind chill advisory. Friday the flow turns zonal with a thermal ridge at 850mb. Temperatures will warm back into the 30s and 40s into the weekend. Sunday night the flow turns back to the northwest, cooling temperatures and bringing and clipper system through North Dakota with a chance of snow. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 914 PM CST Tue Feb 14 2023 MVFR/IFR ceilings will prevail at all terminals except KXWA this evening and through much of the night, with expected improvement to VFR from west to east late tonight through Wednesday morning. Visibility restrictions as low as IFR can also be expected at times this evening into the late night hours from light snow, blowing snow, freezing mist, or any combination thereof. Strong northerly winds will continue through tonight, diminishing from northwest to southeast on Wednesday. && .BIS WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until midnight CST /11 PM MST/ tonight for NDZ005-012-013-019>022-033>035-040>045. Winter Weather Advisory until 9 AM CST Wednesday for NDZ023-025- 036-037-046>048-050-051. && $$ UPDATE...Hollan SHORT TERM...Smith LONG TERM...Smith AVIATION...Hollan
AREA FORECAST DISCUSSION
National Weather Service Sioux Falls SD
901 PM CST Tue Feb 14 2023 .UPDATE... Issued at 849 PM CST Tue Feb 14 2023 Transition from rain to snow quickly crashing in on the I-29 corridor as of mid evening with snow or rain/snow mix now being reported at KBKX and KFSD. At the same time, 30+ kt wind gusts have worked into the same area with 40+ kt gusts observed West River. In general, initial 00z model suite continues to paint an area from near/just east of the James River to near/just west of I-29 as the area of most persistent deformation zone precipitation into the early overnight hours with perhaps the need for a slight eastward adjustment based on current radar trends. Initial wet surface may slow snow accumulations but webcams west of I-29 show accumulation has succeeded (albeit likely fairly wet/slushy accumulation currently). Have made an initial round of changes to adjust the higher axis of POPs and QPF into the previously mentioned zone which raised snow amount in this area and lowered further west. Biggest forecast quandary remains how widespread and persistent any blizzard or near blizzard conditions will be. With the wet nature of the snow, suspect most severe visibility impacts will be during periods of falling snow of which there may only be a couple/few hour overlap between this falling snow and strongest winds. The one exception to this may be along the Hwy 14 corridor from Brookings to Marshall. 00z HREF probabilities for blizzard conditions remain subdued at 10-30%. With all of this in mind, feel that localized and brief near blizzard conditions are certainly possible into the overnight hours for locations for areas from Freeman to Madison to Brookings to Marshall but question whether these conditions will be widespread for a long enough period to warrant an upgrade to a Blizzard Warning. For now, have increased the wording the the going Winter Weather Advisory and will monitor short term trends as the transition continues. && .SHORT TERM...(This Evening through Wednesday) Issued at 300 PM CST Tue Feb 14 2023 KEY MESSAGES: 1. Rain changes to snow from west to east this evening. 2. Northwesterly winds increase during the overnight period, and this in combination with the falling snow will result in hazardous driving conditions. 3. Breezy and colder on Wednesday with patch blowing snow. 4. Moderating temperatures for the end of the week into the weekend. TONIGHT: Current radar and obs indicating light to moderate rain lifting northward across the CWA this afternoon - this associated with a surface low presently situated over central SD and an upper level low lifting through KS and NE. Latest hi-res guidance shows this rain continuing through 00Z, then changing to snow from west to east during the evening as colder air is pulled into the system when the surface low moves to the east. The general consensus among hi-res models and soundings would be for the changeover to begin through the western James River Valley shortly after 00Z, toward the Interstate 29 corridor around 03Z, then in areas to the east toward 06Z. Of note, the HRRR is the slowest model in terms of the changeover, being slightly slower in bringing the colder air eastward. Overall snow amounts have not changed significantly over the previous forecast (though perhaps slightly lower in some areas in response to a slightly slower rain to snow changeover). Any snow that does occur will be light to moderate, with latest HREF ensembles showing hourly snowfall rates running around a half an inch or less. In terms of actual snow amounts, the greatest amounts look to reside roughly through the Highway 14 corridor with 2 to perhaps localized 4 inches possible. Amounts will be less south of there. Perhaps the bigger issue will be the winds, increasing from west to east after 00Z with the onset of cold air advection/an increasing surface pressure gradient/and increasing winds aloft. NBM winds again looked to be on the higher side, so tempered them down a bit, though still looking at gusts of 40 to 50 mph overnight. Fortunately, at this time it appears that the strongest winds may lag the time of heaviest precipitation, though cannot rule out that there will be some overlap, resulting in an hour or two of localized near blizzard conditions for areas - mainly through the Highway 14 corridor into southwestern MN. This is supported by HREF probs, which remain low for the probability of the combination of winds greater than 35 mph and visibility less than 1/4 a mile - which would constitute blizzard conditions. That being said, the higher probs for this combination are over southwestern MN - though it looks to be for a short duration. This will have to be monitored through the evening. It should be noted however, as mentioned in the previous forecast the wet nature of the snow may preclude snow actually blowing around, with the lowest visibilities occurring during actual falling snow. In terms of headlines, current headlines remain appropriate for a combination of wind and snow, though trends will have to be monitored during the overnight for near blizzard conditions as mentioned above. WEDNESDAY: Precipitation should be out of our area by 12Z Wednesday as the upper and surface lows slide into the western Great Lakes region. Strong cold air advection behind the exiting system will result in much colder temperatures with highs in the teens to lower 20s. It will remain breezy, through winds will slowly come down through the day as the surface gradient relaxes and winds aloft taper downward. .LONG TERM...(Wednesday Night through Tuesday) Issued at 300 PM CST Tue Feb 14 2023 Second wave on the backside of the departing low pressure system continues to be poised to move through the central Plains and Midwest states Wednesday evening. Weak quasi-geostrophic (QG) lift will be in place but the better lift looks to remain just south and east of the area. The main wild card in terms of lift comes down to an area of frontogenesis (FGEN) at 700 mb. Medium range guidance shows slight deviations in where this band sets up. BUFKIT soundings also depict mostly saturated profiles with a saturated dendritic growth zone (DGZ) as temperatures cool. Snow ratios look to be around 15-17:1, indicating a lighter fluffy snow. However, soundings will also be slowly drying through the overnight hours, resulting in snow dwindling to very light snow / flurries come Thursday morning. On top of this, hi-res guidance varies in how far north the light snow reaches with some members scrapping our southern forecast area during the Wednesday evening and overnight time frame and others keeping any precip completely out of our area. WPC super ensemble plumes show a wide spread in snowfall totals, though with most clustering at or below an inch. SREF plumes are a bit higher with its plumes clustering between 0-3 inches. These plumes are known to have a high bias so am not putting as much weight into them. Given this lingering uncertainty in where this light snow may fall, have continued with model blended chance PoPs for this time frame. Any snow that does fall will result in only light accumulations from a dusting up to around an inch across the highway-20 corridor and adjacent areas. Aside from light snow chances, northerly winds will be on the decline as Tuesday`s system continues to push off to the northeast, relaxing the surface pressure gradient (SPG). Could still see gusts up to 20-30+ mph, with the strongest gusts occurring Wednesday evening. Low temperatures overnight will fall to the low teens to single digits come Thursday morning. Thursday looks quiet as the base of the upper level trough moves through overhead. This will result in below average highs, barely warming to the teens and 20s. Some breaks in the clouds is possible but a weak, strung out vort lobe will be advecting into the area with just enough moisture to keep mid level clouds locked in place, continuing the trend of partly cloud to cloudy days. With the wave out of here on Friday, temperatures will begin to rebound into the upper 20s to possible low 40s west of the Missouri River along with mostly clear skies in place, making for a much more comfortable day. This is supported by the GFS, Euro, and Canadian ensembles as they all show near to above average high temperatures. Lows look to fall to teens and low 20s overnight. Mainly zonal flow sets up over the weekend, keeping a somewhat persistent dry, westerly flow aloft locked in place. Above average temperatures look to continue through the weekend and into early next week along with dry conditions. This is again supported by ensembles which continue to show near to above average temperatures this weekend. Medium range guidance begins to diverge beginning next week but Monday looks like it will be another warm day before cooler conditions return for the middle of next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 518 PM CST Tue Feb 14 2023 Rain currently ongoing mainly east of the James River will pivot slightly westward this evening with a changeover to snow from west to east thru the evening. Meanwhile, within this area of rain, IFR/LIFR ceilings and vsbys will continue. Northwesterly winds will also be on a rapid increase from west to east with gusts to around 40 kts at times into Wednesday morning. During periods of blowing snow, vsbys at or below 1/2 mile are possible, particularly toward the Hwy 14 corridor. Precipitation will end prior to daybreak with an improvement toward MVFR conditions for Wednesday. Winds will remain breezy through Wednesday but should peak overnight. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...Wind Advisory until 6 AM CST Wednesday for SDZ071. Winter Weather Advisory until 6 AM CST Wednesday for SDZ038-050- 052>054-057>061-063>070. Winter Weather Advisory until 9 AM CST Wednesday for SDZ039-040- 055-056-062. MN...Winter Weather Advisory until 9 AM CST Wednesday for MNZ071-072- 080-081-089-097-098. Wind Advisory until 6 AM CST Wednesday for MNZ090. IA...Winter Weather Advisory until 9 AM CST Wednesday for IAZ001. Wind Advisory until 6 AM CST Wednesday for IAZ002-003-012-013. Wind Advisory until 6 AM CST Wednesday for IAZ020-031. NE...Wind Advisory until 6 AM CST Wednesday for NEZ013-014. && $$ UPDATE...Kalin SHORT TERM...JM LONG TERM...Meyers AVIATION...Kalin
Area Forecast Discussion
National Weather Service Gray ME
732 PM EST Tue Feb 14 2023 .SYNOPSIS... Temperatures remain above average through the week before peaking on Thursday into Friday as ridging builds along the East Coast. A strong cold front crosses the area on Friday, bringing an end to the near record warmth. This front will bring mostly rain to the region with cooler temperatures arriving on Saturday. High pressure builds across New England for next weekend, with warmth likely returning early next week once the high slides offshore. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 715pm Update...Temps have come down quickly off their highs today, as have winds. Will continue to monitor temp trends, but so far conditions are quite good for radiational cooling over the next 3 to 6 hours. That is, until a shelf of cirrus advancing towards the region from the SW. Trends will be a little trickier after midnight once this cloud cast is overhead, as it will likely hamper cooling a bit, but not cut it off completely. Also competing will be light winds becoming southerly to bring WAA and moisture in. Some hires guidance is hinting at lower vis across the southern Kennebec Valley after midnight. This would be fog development, but would really rely on near sfc temps falling quickly before midnight and enough moisture getting pushed onshore once winds swing around. RAP and some past runs of HRRR depict this, but will continue to monitor later runs. Previous Discussion... Upslope snow showers across the mountains diminish late this afternoon as high pressure builds into New England. Downslope winds across the lower elevations have brought warm temperatures this afternoon with southern areas warming to near 50 degrees. Overall this warm trend is expected to continue overnight with temperatures likely only falling to near freezing across southern areas. The ridge axis passes overhead tonight, allowing winds to ease through the evening. With a warm airmass in place, temperatures should locally range widely tonight between low spots and areas of snow cover and higher locations. With that in mind, the overall trend is for expected lows to dip into the mid teens across the north, and near freezing across southern and coastal areas, but wide jumps of around ten degrees are likely overnight within very short distances. High clouds start to spill in late tonight as a warm front approaches from the southwest. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... The warm front sweeps northeastward tomorrow morning as low pressure moves into the Great Lakes and helps further enhance a warm airmass across the region. The high-res guidance has been consistent over the last few runs with bringing a narrow band of precipitation through with this front, with showers across southern areas and a light wintry mix further north where surface temperatures are cooler. The column will have to saturate before any of this could reach the ground, and with it being such a brief period of precip there is some limited confidence that this would actually be possible. With this in mind, POPs were generally kept to chance for tomorrow morning until a stronger signal arises for this brief and minor feature generating enough precip to reach the ground. After the front passes through, temperatures soar into the low to mid 50s across southern areas tomorrow afternoon, with 40s expected elsewhere. Temps are going to be about 7C warmer than today at 925mb tomorrow afternoon, but cloud cover looks like it will limit just high the temps will be able to climb. With a little more sunshine, upper 50s would easily be possible across southern New Hampshire, and are not out of the question. Southwesterly flow continues tomorrow night as high pressure slides offshore and the low tracks through the Great Lakes. Southern areas likely stay very warm for this time of year, with lows holding in the 40s. Closer to the mountains and inland areas with snow cover, there are likely to be times when the wind eases that temperatures will be able to fall to near freezing overnight, then warming again by ten degrees when the wind returns. So overall a see-saw pattern of temperatures likely yields lows in the low to mid 30s across inland snow covered areas, while the snow-free regions see lows mainly in the 40s. POPs also increase along the Canadian border tomorrow night as a weak wave passes through southern Quebec, bringing the chance for some scattered showers. && .LONG TERM /THURSDAY THROUGH TUESDAY/... We continue to be on track for near record warm temperatures Thursday as a warm front ahead of low pressure over the Ohio Valley pushes north of the area on Thursday. This along with high pressure over the western Atlantic Ocean will result in a warming southwest wind direction. With existing record high temperatures cooler on Thursday than Friday (see climate section below), there is a better chance of breaking record highs on Thursday. In addition with most of the region remaining well in the warm sector Thursday Night, record warm low temperatures are possible. While Thursday will be mainly dry, showers will become likely Thursday night and Friday as low pressure moves northeast up the St. Lawrence Valley. This westerly track will keep the precipitation showery with the steadiest precipitation remaining to our north and west. A cold front associated with this system will sweep across the area during Friday Morning. It looks less likely that records will fall Friday due to the fact that the records are higher and the cold front will likely cross the area in the morning thereby limiting warmth...although southern most NH and SW Maine will still be above normal for highs. Conversely over the mountains and north falling temperatures may lead to some light snow accumulations. Precipitation amounts should be rather light...generally around quarter of an inch. Showers will come to an end Friday Afternoon and evening. High pressure over the nations mid section will result in a colder northwest flow Saturday which will ease some on Sunday. Expect dry conditions over the weekend. Early next week low pressure will move well north and west of the area through Canada. A weak front pivoting around this system may result in some showers Monday into Tuesday. Global models are in general agreement with the above scenario`s. Generally followed the NBM but raised lows for Thursday night. Also lowered highs for Friday over Northern areas due to quicker cold frontal passage. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Short Term...Primarily VFR conditions continuing at all terminals through tomorrow night. Light and variable winds this evening, becoming southerly. Some southwest gusts to 25kts are possible during the daytime tomorrow. Ceilings lower tomorrow morning for a period, but are expected to remain at VFR heights. Long Term...MVFR conditions Thursday with a few showers late over southern NH. MVFR with areas of IFR Thursday Night into Friday with scattered rain showers region wide...changing to snow showers over the Mountains. MVFR to VFR conditions returning Friday Night through Sunday. && .MARINE... Short Term...High pressure builds across the waters tonight. The high moves east tomorrow morning and increasing southwesterly flow brings SCA conditions again tomorrow evening and tomorrow night. Long Term...Conditions below SCA Thursday and Thursday Night. SCA conditions later Thursday Night and Friday possible building to Gales over the outer waters late Friday and Friday evening with SCA`s continuing into early Saturday. && .CLIMATE... Well above normal temperatures are expected later this week. Current forecasts would keep highs below records for Wednesday. However...warmer temperatures on Thursday suggest a a better shot at record highs. Below are the record high temperatures for Thursday. Portland, ME: 51F in 1981 Augusta, ME: 53F in 2006 Concord, NH: 59F in 2006 Thursday Min Max: Portland, ME: 39F in 1984 Augusta, ME: 37F in 1984 Concord, NH: 40F in 1984 The records for Friday are below although it is looking less likely that these records will fall. Portland, ME: 58F in 1981 Augusta, ME: 57F in 1981 Concord, NH: 59F in 2022 && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ NEAR TERM...Clair/Cornwell SHORT TERM...Clair LONG TERM...Lulofs
Area Forecast Discussion
National Weather Service Wichita KS
542 PM CST Tue Feb 14 2023 ...Updated Aviation Discussion... .SHORT TERM...(This evening through Friday night) Issued at 227 PM CST Tue Feb 14 2023 Dry weather expected for tonight as current upper level low pressure system races northeast away from Kansas. Meanwhile the next upper level low pressure system currently over Nevada will move east across the Rockies tonight and eject out into western Kansas by Wednesday night. Snow will begin to fall Wednesday morning over western Kansas and spread eastward into central Kansas during the mid to late afternoon hours. The snow intensity looks to ramp up Wednesday evening due to combination of vertical motion being maximized in dendritic snow growth zone, and steeper lapse rates/frontogenesis in the mid-levels yielding moderate to heavy snow at times with a 4 to 7 hour duration over central Kansas. There could also be a brief period of a sleet/snow mix across parts of south central Kansas into the Flint Hills(Kingman to Cottonwood Falls line) during the Wednesday evening hours. This winter mix transition zone will quickly change over to all snow and shift eastward into southeast Kansas as deeper colder air removes the elevated warm nose aloft. Another concern will be the winds causing some blowing and drifting of snow over central Kansas where the heaviest snow amounts are forecast. We will keep the current winter storm watch going which continues to message our highest confidence area that could see the biggest winter weather impacts. Highest snow amounts of 4 to 6 inches are still likely over central Kansas with lower amounts expected over southern Kansas. Snow is expected to taper off over Kansas Thursday morning as the upper level system races to the northeast. Cold below normal temperatures will be in place for Friday, especially for the fresh snow pack areas across central/south central Kansas. .LONG TERM...(Saturday through Tuesday) Issued at 227 PM CST Tue Feb 14 2023 Dry weather conditions and a nice warming trend look to prevail across the region for this weekend into Monday. Models show the upper level pattern transitioning to a northwest flow regime and a push of colder air possibly arriving on Tuesday. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 537 PM CST Tue Feb 14 2023 Winds will gradually turn westerly this evening, becoming northerly later tonight into Wednesday morning, as a cold front moves in from the north. Increasing cold advection from the north should support MVFR ceilings later tonight through tomorrow, especially across central Kansas. Unsure how far south these MVFR ceilings will reach later tonight-Wednesday, with the RAP and NAM supporting these low clouds reaching down into southern Kansas, while the GFS is not nearly as bullish. Light snow should commence across central Kansas by late afternoon/early evening Wednesday, as the next storm system approaches from the southwest. && .FIRE WEATHER... Issued at 227 PM CST Tue Feb 14 2023 Combination of warmer temperatures and gusty winds will create very high grassland fire danger levels across much of the region for Saturday afternoon. && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 33 45 19 34 / 0 10 90 10 Hutchinson 32 40 17 32 / 0 30 90 10 Newton 32 43 17 31 / 0 10 90 20 ElDorado 33 46 19 32 / 0 10 90 20 Winfield-KWLD 34 51 21 36 / 0 10 60 10 Russell 28 31 15 30 / 0 70 100 10 Great Bend 29 34 15 31 / 0 70 100 10 Salina 30 37 16 32 / 0 30 100 20 McPherson 31 39 16 31 / 0 30 90 20 Coffeyville 36 56 25 35 / 0 0 30 10 Chanute 35 52 23 33 / 0 0 50 20 Iola 35 51 22 32 / 10 0 60 20 Parsons-KPPF 36 55 24 34 / 0 0 40 10 && .ICT WATCHES/WARNINGS/ADVISORIES... Winter Storm Watch from Wednesday afternoon through Thursday morning for KSZ032-033-047>051. Wind Advisory until 6 PM CST this evening for KSZ072-094>096- 098>100. && $$ SHORT TERM...CDJ LONG TERM...CDJ AVIATION...ADK FIRE WEATHER...CDJ
Area Forecast Discussion
National Weather Service Lincoln IL
727 PM CST Tue Feb 14 2023 .SYNOPSIS... Issued at 345 PM CST Tue Feb 14 2023 Windy conditions will continue tonight as south to southeast winds gust 35 to 45 mph this afternoon and tonight, and turn southwest overnight. Rain showers will continue into this evening before conditions dry out overnight. Lows tonight will be in the 40s for most areas, followed by highs ranging from lower 40s northwest of the Illinois River to lower 60s south of I-70 Wednesday. && .UPDATE... Issued at 727 PM CST Tue Feb 14 2023 Lots of items under consideration for the evening update. 1) Wind concerns: After some gusts 40-45 mph or so over the last few hours, a significant tailing off of the wind has been occurring over the western and southern reaches of the forecast area, especially as skies cleared out. VAD winds from our radar still show 50-60 knots around 2,000 feet, though this is not working its way down to the surface. Working out the specifics with neighboring offices on trimming back on the wind advisory, most likely by the top of the hour. Still some concerns with the I-74 corridor area between Peoria and Danville and will likely let that ride longer. 2) Rain concerns: The rain exited quite a bit faster than earlier projected, with most areas dry before 7 pm. However, a small area of showers with embedded thunderstorms is lifting northeast from central Missouri. Latest HRRR forecast soundings show a couple hundred joules of MUCAPE west of the Illinois River by 9-10 pm. With the increase in showers across the northwest CWA again late evening, have also introduced a mention of isolated thunder in this region. Latest high-res guidance has most of this activity north of the forecast area by 1 am or so. 3) Sky concerns: Despite the extensive clearing as of late, nighttime microphysics imagery is showing a fairly widespread expansion of stratocumulus up from southern Illinois, not to mention the clouds associated with the Missouri showers. Sky trends have been updated a couple times already to reflect the clearing. A more widespread increase in clouds is expected over the northern CWA overnight associated with the upper low currently in western Iowa. && .SHORT TERM...(This evening through Wednesday) ISSUED AT 345 PM CST Tue Feb 14 2023 Low pressure centered over KS this afternoon continues to lift northeastward toward the upper Midwest, and has spread shower activity, albeit light, into central IL this afternoon. More widespread and heavier showers should arrive late this afternoon through mid-evening, bringing tenth to quarter inch rainfall amounts. These showers should exit the area by midnight. More significant will be the winds, with south- southeast winds continuing to strengthen with the approach of the low and stronger pressure gradients, as well as somewhat better mixing potential with an inversion dissipating with cooler temperatures aloft. Although winds may trend down for a few hours late in the evening, the passage of a cold front should bring cold advection in the early morning hours that could extend windy conditions, or potentially bring some of the strongest winds of this storm from around 3 to 6 am for areas east of I-55 & north of I-70. Have extended the wind advisory to 9 am for these areas, while the remainder of central/southeast IL maintain the wind advisory until 3 am. Temperatures tonight will be fairly mild, especially this evening, then lowering late in the night. Still only expecting lows around 40 from I-55 westward upward to lower 50s south of I-70. Cold advection Wednesday should hold temperatures down to the 40s for many areas north of I-72, but still some milder 50s to the south and as high as lower 60s south of I-70 should take place. && .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 345 PM CST Tue Feb 14 2023 The next storm system, currently digging into the southwest US, will track toward the I-70 corridor in Illinois for early Thursday, with precipitation likely to be from early Thursday morning through Thursday afternoon. Concerns with this system mainly revolve around precipitation type for areas north of I-72, and thunderstorm potential south of I-72, especially south of I-70. A few to several hundred J/kg CAPE could arrive from I-70 southward early Thursday morning through around noon, depending on exact storm track, combined with strong shear, and this could develop some severe thunderstorms for which SPC has a Marginal Risk outlined. Farther to the northwest, it appears a warm nose wrapping around the low center will spread over subfreezing surface temperatures for a time Thursday morning around the Illinois River Valley, and this could bring some mix of wintry precipitation and freezing rain. So far, ice accumulation looks to be light. Snow accumulation could range up to a few inches northwest of the Illinois River, and an inch wouldn`t be out of the question for areas north of I-72 and west of I-55. The large gradient in temperatures will obviously continue across the area Thursday, with highs from mid 30s west of the Illinois River to near 60 south of I-70, the cold air behind Thursday`s system will sweep across the entire area by Friday, for highs ranging from upper 20s to mid 30. The cold temperatures look to be short-lived, with highs rebounding to upper 40s and 50s Saturday through Monday as southerly flow returns. Next chances for precipitation look to be Monday into Tuesday as another low pressure system tracks into the area from the Pacific NW and northern Rockies. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 526 PM CST Tue Feb 14 2023 MVFR ceilings have mainly been in narrow corridors associated with heavier rain showers as of late, but there is some potential for this to expand over eastern Illinois for a few hours this evening. Further west, a brief clearing trend will take place, but ceilings increase again later in the evening. Looking into the overnight hours, a more widespread cloud deck around 1500-2000 feet is expected to move into the region from the northwest. Impacts are most likely at KPIA/KBMI, but there is some potential for the fringe of the cloud deck to reach KSPI/KDEC toward 12Z. Improving ceilings are expected during the afternoon. In terms of wind, winds are starting to pick up as the rain ends, with recent gusts to 37 knots at KPIA/KSPI. Local radar wind profile is showing 50 knot winds as low as 2,000 feet and some of these winds may help enhance the surface gusts. While starting off from the south, a trend toward the west/southwest will occur overnight. By midday, a more substantial tapering of the wind will spread from southwest to northeast. && .ILX WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 3 AM CST Wednesday for ILZ027>031-036-037- 040-041-047>052-061-062-066>068-071>073. Wind Advisory until 9 AM CST Wednesday for ILZ038-042>046- 053>057-063. && $$ UPDATE...Geelhart SYNOPSIS...37 SHORT TERM...37 LONG TERM...37 AVIATION...Geelhart
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
851 PM CST Tue Feb 14 2023 ...Update. .SYNOPSIS... Issued at 304 PM CST Tue Feb 14 2023 KEY MESSAGES... * Strong storm system currently centered across KS will move northeast away from the area tonight. Strong gusty northwest winds can be expected tonight into the first half of Wednesday in the wake of the system. * A second system will cross KS and southern NE Wednesday afternoon and night bringing snow to those areas. * Warmer weather returns this weekend to the region. && .UPDATE... Issued at 847 PM CST Tue Feb 14 2023 A forecast update is in place for wind gusts of 50 to 55 mph this evening. The wind gust forecast leans on the HRRR model which shows a corridor of strong wind gusts swinging through ncntl Nebraska. Winds should subside around midnight or early in the morning. Sporadic high wind gusts may develop; KBBW ASOS gusted to 58 mph around 7 pm this evening. && .SHORT TERM...(This evening through Wednesday night) Issued at 304 PM CST Tue Feb 14 2023 First system continues to to move northeastward across the Central and Southern Plains this afternoon. This is a very moist system with high PWATS streaming northward from the Gulf within warm conveyor located across the Missouri River Valley. Lack of cold air with this system is keeping most of the precipitation rain. The exception is dynamic cooling processes on the immediate western side of the closed upper circulation where some wet snow is found. This has been occurring across western KS this afternoon. As the closed circulation moves into eastern NE this evening expect a change over to wet snow across eastern portions of north central NE. Expecting little accumulation however with all precipitation ending by midnight. The other story will be the strong northwest winds that develop this evening. A deep surface low will be located across eastern NE this evening, with a cold front surging southeastward across western and north central NE. Bufkit sounding data suggests wind gusts of 45-50 mph possible across portions of north central NE and 40-45 across the rest of the area. CAA will be strong tonight with temperatures falling quickly into the teens overnight. Little recovery in temperatures are expected Wednesday with struggling to reach much above 20F. The next system will arrive Wednesday afternoon into Wednesday night. This is a potent system as well but moisture will not be as plentiful. Still it is a dynamic system and snow is expected to materialize. Much of the moisture will be carried from the Pacific and be located in the mid-levels. So expect a top down type saturation event and a rather sharp northern cut off to the accumulating snow. This cutoff will be located across southwest NE and should stay south of I-80 according to most Hi-Res models. Snow could be locally heavy within area of strong FGEN that should be located near the NE/KS border. Appears our southern 3 counties stand a good chance of accumulation greater than 3" and have issued a winter weather advisory to account for this. As mentioned though the cutoff will be sharp to the north, with little accumulation expected along I-80 where drier air will be in place. Any slight northward shift could bring more snow closer to I80 however and will be monitored. System departs Wednesday night with snow ending by midnight. .LONG TERM...(Thursday through Tuesday) Issued at 304 PM CST Tue Feb 14 2023 Upper level ridging builds across the western CONUS late this week and then flattens to more zonal flow during the weekend. A return to very mild weather with Sunday having potential to reach 50F across parts of the area. Flow aloft then transitions to northwest early next week with a series of cold fronts bringing an end to the mild weather. It`s unclear how the pattern will evolve. The GFS and EC handle the upper level energy differently, with the EC holding much of the energy off the west coast and much drier for our area as a result. All guidance though suggest it will be much colder late next week as a batch of arctic air plunges southward into the region. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 519 PM CST Tue Feb 14 2023 The main concern at both sites will be strong winds continuing into Wednesday afternoon. North northwest gusts up to 35 to 40 knots will continue through the overnight with winds beginning to decrease by late morning. Gusts up to 25 to 30 knots will be possible though through Wednesday afternoon before completely diminishing after sunset. For KLBF, light snowfall will move in south of I-80 tomorrow afternoon as well. Majority of the precipitation will remain south of the terminal, but a few isolated snow showers may briefly impact the airport in the afternoon and early evening. Any accumulations should be under an inch but reductions in visibility will be likely due to falling snow. && .LBF WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from noon CST /11 AM MST/ Wednesday to 6 AM CST /5 AM MST/ Thursday for NEZ069>071. && $$ UPDATE...CDC SYNOPSIS...Taylor SHORT TERM...Taylor LONG TERM...Taylor AVIATION...Kulik
Area Forecast Discussion
National Weather Service Louisville KY
935 PM EST Tue Feb 14 2023 ...Forecast Update... Issued at 928 PM EST Tue Feb 14 2023 The concern today has been the winds which prompted a Wind Advisory to be issued yesterday for tonight. As the low level jet has increased this evening, we have had some gusty winds. We even had a isolated reading or two above 40 mph, but overall gusts are falling short of the earlier forecast as an inversion is forming above the ground. There is still time to see increased wind gusts later tonight, but it`s beginning to look less likely the region will see widespread criteria level winds. Paducah has already dropped their advisory. If trends continue, it`s likely we will drop the wind advisory early. .Short Term (Now through Wednesday)... Issued at 300 PM EST Tue Feb 14 2023 Key Messages: - Strong gusty winds expected, especially this evening - Light rain showers this evening - Near record warm temperatures Discussion: The first of two distinct storm systems affecting the country will bring its influence to us late this afternoon and evening. Already seeing some very light radar returns across the region now in a weak warm-frontal type lift ahead of the system. Expect another wave of isentropic lift this evening to bring in some light rains across the region. This lift will be brief over our area, so only expecting at most a couple tenths of an inch of precip through daybreak Wednesday. The more significant sensible weather will be the gusty winds this evening. High-res guidance shows 50-60 kt winds at 925 mb, with the ARW and HRRR showing ~60 kt winds moving across central KY south of the Parkways. Will have to monitor for a short-fused High Wind Warning south of I-64 this evening. HREF 90th percentile gusts are in the 55-60 mph range before midnight for central Kentucky, so it`s not out of the realm of possibility, but not enough confidence to upgrade at this time...especially given a bit less wind so far this afternoon compared to guidance. As the first system departs early Wednesday, we`ll be solidly in the warm sector for the daytime period. Expecting near record high temperatures (see Climate section below) as well as dry and breezy conditions. The dry and breezy part of that helps in a decision to lean towards the warm side of the guidance envelope...especially for the northern half of the forecast area, where skies should have less cloud coverage. .Long Term (Wednesday Night through Monday)... Issued at 315 PM EST Tue Feb 14 2023 Key Messages: - Strong to severe storms possible late Wednesday night and Thursday - Unseasonably warm and breezy through Thursday Wednesday Night... A mid/upper level trough propagates eastward over the central Plains Wednesday night. Favorable upper level divergence is noted across the MO and Lower OH Valleys, especially within the right entrance region of an intensifying upper level jet streak over the Great Lakes. Meanwhile, an impressive 100 kt SW speed max at 500 mb will stream from Oklahoma across Missouri. Sfc low pressure over central OK around 00z Thu is forecast to reach SEMO by 12z Thu, with a warm front extending northeast through southern Indiana. Wednesday night starts off dry at 00z, but rain and thunderstorm chances will increase from south to north after 05z Thu. An initial band of convection is likely to push into southern KY around 06z Thu on the nose of a 45-50 kt SW LLJ. This first wave may stay primarily elevated with a low-level inversion in place. Modest elevated instability does look likely and will support isolated to scattered thunderstorms. Deep-layer and low-level shear are both quite strong, with a veering hodograph in the lowest 1 km. An elongated hodograph, in addition to backing between 2-4 km, should support splitting storms. Left movers could be capable of marginally severe hail. However, the main severe weather risk Wednesday night develops immediately behind/south of the initial band. Additional sct to num showers and storms should spread NE from western TN and could be rooted at the sfc by 09-12z Thu. Weak sfc-based instability is most likely along and south the Ohio River and roughly along and west of the I-65 corridor (southwestern quadrant of CWA), which lines up pretty nicely with the new SPC Day 2 Marginal Risk. Isolated damaging winds and/or a brief tornado would be the main threats with stronger convection. Thursday... The threat for strong to severe storms spills into Thursday with ongoing convection at 12z. Strong SW flow will continue to advect warm, moist air into the region ahead of the cold front, which is forecast to sweep across the area Thursday evening. At this point, it is not yet clear if there will be two or three distinct "waves" of convection on Thursday. After morning convection, at least one lull seems likely. Additional showers and thunderstorms are expected in the afternoon ahead of the cold front. A modest plume of MLCAPE will be in place in the warm sector. Ensemble probabilities suggest a 50-60% chance for greater than 150 J/kg SBCAPE. A narrow corridor of 200-250+ J/kg seems probable with sfc dewpoints approaching 60 F. Sfc low pressure should continue northeastward from SEMO across central Indiana during the day. There is a bit less low-level veering as we move into the afternoon and evening hours, with the sfc warm front remaining just off to the north. Still, plenty of shear in place to support both low-topped supercells and bowing line segments. Damaging winds and short-lived tornadoes are both on the table. Thursday Night and Beyond... After a warm, breezy, and at times stormy Thursday, much colder air spills into the region Thursday night behind the cold front. Lows in the upper 20s to lower 30s are expected Friday morning. Clouds should linger into Friday morning, with an improving trend later in the day. Afternoon highs will be limited to the mid/upper 30s. Cool weather continues into the weekend as high pressure builds over the region. Expect Saturday morning to be the chilliest with readings well below freezing. Afternoon highs will then warm each day this weekend into early next week. 60+ degrees looks likely by Monday, which is also when the next chance for rain arrives. && .Aviation (00Z TAF Issuance) Issued at 630 PM EST Tue Feb 14 2023 IMPACTS: - Gusty 30+ kt winds - LLWS with strong low-level jet Discussion: Forecast remains on track as main impacts are expected from wind and low level wind shear. SSE winds are currently beginning to gust over 20 knots over southern Indiana and central Kentucky. Gusts are expected to increase to around 30-35 knots as winds veer towards the SW in the coming hours. A strong low-level jet will cause LLWS during most of the overnight hours. Rain showers will move through the region, but ceilings and visibilities are expected to remain in VFR ranges. && .Climate... Updated at 200 PM EST Tue Feb 14 2023 A mild and breezy weather pattern will set up over the region through mid week, and some record temperatures could be in jeopardy as a result. The most likely records to be broken would be high temperatures on Wednesday, although some warm minimum temperatures could be at risk Wednesday as well. Right now, it appears the warm min records will stay just out of reach, but this pattern usually promotes very mild overnights. Thursday`s warm min records are not in jeopardy, thanks to the cool down expected Thursday afternoon and evening. ================== Near-Record High Temperatures ================== Wednesday 2/15/2023 Max T Fcst/Record (Year) Min T Fcst/Record (Year) Louisville: 75/74 (2018) 57/62 (2018) Bowling Green: 76/77 (2018) 57/63 (2018) Lexington: 75/76 (1945) 55/60 (2018) && .LMK WATCHES/WARNINGS/ADVISORIES... KY...Wind Advisory until 7 AM EST /6 AM CST/ Wednesday for KYZ023>043- 045>049-053>057-061>067-070>078-081-082. IN...Wind Advisory until 7 AM EST /6 AM CST/ Wednesday for INZ076>079- 083-084-089>092. && $$ Update.........KDW Short Term.....RJS Long Term......EBW Aviation.......KDW
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
943 PM CST Tue Feb 14 2023 .UPDATE... Issued at 931 PM CST Tue Feb 14 2023 Conditions remain mixed in the low levels this evening, more so than normally would be expected after dark. The low level jet has maximized over northeast Illinois, and thus occasional wind gusts to 45 mph, and a few sporadic gusts in the lower 50 mph range, including at Chicago O`Hare recently with a 1-minute ob at 48 kt (55 mph). These gusts have also been maximized in the urban areas that are a bit warmer. We have correspondingly bumped up the start of the Wind Advisory for areas south of I-80 but including Cook/DuPage this evening, even though widespread wind gusts of 45-50 mph have been somewhat limited away from the metro area. This seemed prudent given the band of showers over west central IL will encounter this higher low level jet maximum and may be able to overperform what they`ve been doing upstream. There will likely be a lull in winds after this band of showers moves through overnight. A lightning strike cannot be ruled out, but given the main instability axis skirts the area to the northwest, this would be the exception. Latest AMDAR soundings do have a bit of a warm nose at 3000 ft, but there is still 50+ kt of winds below that, so we will have to watch the 11pm - 2am window for some sporadic higher gusts from these showers. KMD && .SHORT TERM... Issued at 1258 PM CST Tue Feb 14 2023 Through Wednesday night... CONUS satellite imagery augmented by a recent hand surface and RAP analyses depict a maturing surface cyclone over the Southern Plains within the left exit region of an intensifying 150 kt 250mb jet streak across the Lower Mississippi River Valley. Arcs of showers continue to expand near and ahead of the developing surface low with a broad (and intensifying) WAA regime. The first showers are now crossing northern Illinois, though the dry low-level airmass (characterized by surface T/Td spreads of 15-20 degrees) has thus far chewed up most raindrops. Continued top-down moistening via evaporation should eventually allow for raindrops to start dotting the ground this afternoon. The next band of rain is much broader and encompasses much of Iowa and Missouri, and is on track to reach our area around or just after sunset. Accordingly, we are anticipating a 2-4 hour period of showers this evening before tapering takes place from west to east by 10 PM. As the surface low matures and lifts northeastward over western Iowa this evening, the low-level pressure gradient will also tighten allowing for south to southeasterly winds to gradually intensify with gusts of 30-35 mph becoming common by sunset. Tonight, the surface low is expected to reach peak intensity (~984 mb or so) while entering southern Minnesota as a dry slot noses into the Lower Great Lakes and an impressive 60-70kt 850-700mb LLJ slides overhead. Cooling mid-level temperatures around the periphery of the low and mid-level drying within the northeastward-spreading dry slot will steepen mid-level lapse rates and maintain the integrity of a pool of 150-250 J/kg of MUCAPE spreading northeastward from Missouri into northern Illinois. At the same time, a narrow plume of surface dew points ranging from 45-50 degrees currently in southwestern Missouri will spread northeastward, causing low-level lapse rates to improve modestly. Taken together, a band of low-topped convection originating near the MO/KS/IA borders this evening may survive and sweep across the area overnight, particularly between 04Z/10PM and 7Z/1 AM. With strong low-level wind field in place (re: LLJ) and steepening low-level lapse rates (re: low-level moisture advection), any taller convective shower may efficiently transport wind gusts of 45-50 mph toward the ground. Such a threat appears highest northwest of Interstate 55 in closer proximity to the cold core of the low and hence better MUCAPE. After touching base with SPC, we felt the probability of severe-caliber gusts was too low to warrant a formal mention in a severe weather outlook, though be aware a "pop" of winds may accompany any shower overnight. Toward daybreak, surface winds and gusts are expected to increase markedly as mixing heights build into the base of the departing low- level wind field and surface pressures rise some 8-12mb/6 hours. BUFKIT overviews depict peak momentum transfer of 45-50kt at the top of the forecast mixing channel, which should support surface wind gusts of 45-50 mph across much or northern Illinois and northwestern Indiana. For this reason, we opted to expand the inherited Wind Advisory to the Wisconsin border with the expectation for the strongest winds to occur primarily between 6-10 AM CST (we padded the timing of the official product by 2-3 hours on each side). While winds will gradually decrease through the afternoon hours, it will feel much colder than the past few days as temperatures slowly fall through the 40s and eventually 30s by evening. Borchardt && .LONG TERM... Issued at 314 PM CST Tue Feb 14 2023 Thursday through Tuesday... The main weather highlights during the period are: * Increasing threat for a significant band of accumulating snow across parts of far northern IL Thursday. Have issued a Winter Storm Watch for Winnebago, Boone and Ogle counties, where the greatest threat of 6"+ snow amounts and the most significant impacts resides. * Travel impacts also likely south of the watch area, potentially as far southeast as the I-55 corridor on Thursday as a result of accumulating ice and snow in a wintry mix. * Turning sharply colder Friday, but then warming up again into next weekend. There continues to be some model differences with the exact track our next storm system will take on Thursday. While this does continue to add uncertainty to the finner scale details of the forecast, a general model/ensemble consensus does point at a system track that would favor potentially 6"+ snow amounts across far northern parts of IL (especially near the WI state line), and a wintry mix south of this heavy snow band across the remainder of northern IL. While a winter weather advisory will likely be needed for much of northern IL for Thursday, we have opted to issue a winter storm watch for Winnebago, Boone and Ogle counties in far northern IL for Thursday. A southwest to northeastward oriented baroclinic zone will sag southward into far northwestern IL and adjacent areas of southern WI and eastern IA on Wednesday following the departure of the potent storm system tracking across the Upper Midwest tonight. This baroclinic zone will be a major driver in the expected band of heavy snow likely to fall across northern sections of the area Thursday. Mid-level deformation will strengthen along the storm systems northwestern periphery as it tracks across central IL into IN into Thursday, and this will induce what looks to be a rather impressive southwest to northeast oriented band of 850-700 mb frontogenesis somewhere right across eastern IA into far northern IL and southern WI during the day. What potentially makes this even more interesting is the fact that the frontogenetic response for upward ascent is likely to occur beneath the favorable entrance region of a healthy upper level jet over the Upper Great Lakes. Steepening mid-level lapse rates, and low static stability will also be favorable for heavy snowfall rates (1"+ per hour) within this band of snow. As mentioned previously, questions still remain with the exact placement of the heaviest band of snow. However, given that our far northwestern counties will be in close proximity to the main threat area, we felt it prudent to include them in the winter storm watch. Areas south of the winter storm watch will not be out of the woods for travel impacts on Thursday. Northerly surface winds are expected to drag a subfreezing near surface airmass southward across much of northern IL through the morning, and this adds concern for freezing rain and sleet, especially through the morning as a warm layer aloft will initially be in place across much of northeastern IL. It also appears that moisture in the DGZ will be lacking with southward extent over northern IL during the morning, so freezing drizzle/rain are probable in ares that see subfreezing temperatures develop (most likely along and northwest of I-55). Farther south and east temperatures should remain above freezing through the morning, so any precipitation that falls in my far southeastern areas should be liquid. While this will not be a major icing event, minor ice and sleet accumulations are likely to result in some travel impacts for the Thursday commute, perhaps as far southeast as around the I-55 corridor. We should then see a gradual transition over to snow across most areas through the afternoon on Thursday as better moisture in the DGZ works eastward with the approach of the main mid-level disturbance. The precipitation will then end (for most) into Thursday evening. The only exception to this is that some lake effect snow showers are likely to persist over parts of Porter county IN into Friday morning. Colder air will briefly make a return on Friday as the aforementioned baroclinic zone shifts southeastward across the area, making way for a colder air mass to spill in as high pressure builds across the region. This will be short lived, however, as southerly to southwesterly flow develops Friday night into Saturday on the backside of the surface high. This will set up a quick warm-up and dry period of weather for the weekend. However, colder and more active weather may make a return the area into the middle of next week. KJB && .AVIATION... For the 00Z TAFs... Forecast concerns for the terminals... *Gusty 30 to 40 kt winds through Wednesday afternoon *Rain showers persisting through early Wednesday morning with pockets of heavier showers after midnight *Developing MVFR ceilings this evening lingering through Wednesday afternoon A strong 986 mb surface low resides over northern Iowa this evening which is generating breezy southeasterly winds at the terminals. While gusts have eased a bit late this afternoon, gusts are expected to increase into the 30 to 35 kt range this evening as a stout low-level jet moves overhead. Further intensification of the winds is expected after 06z this evening in the wake of a cold front as cold advection allows for better mixing and gusts to reach into the 35 to 40 kt range. Wind directions will also become west-southwesterly late this evening behind the cold front. The gusty winds will persist through Wednesday afternoon before gusts ease heading into Wednesday evening. Additionally, a broad area of light to moderate rain continues to lift northward across Illinois ahead of the aforementioned cold front. These showers will continue to move through the area this evening with periods of showers through the night before showers come to an end early Wednesday morning. While the main area of rain looks to only cause minor visibility reductions, a more robust area of convective showers is being observed over western Missouri and is expected to move into northern Illinois around 05z this evening. Forecast soundings continue to show that instability would be increasing as these showers approach which should allow for a brief period of heavier rainfall, reduced visibility, and possibly a rumble or two of thunder. Given the marginal instability have decided to forgo a formal thunder mention in the TAFs, but did maintain a TEMPO for the heavier rain and low visibility at RFD, ORD, MDW, and DPA. At this time GYY looks to remain just south of these convective showers so I have forgone the lower visibility mention. Finally, MVFR ceilings are being observed under these areas of showers and are expected to move over the terminals within the next couple of hours. While MVFR ceilings are expected to linger through Wednesday afternoon, there is a chance that some scattering out of the ceilings may occur Wednesday morning. Confidence is rather low on this occurring as soundings show clouds remaining in the 2000 to 3000 ft layer through the rest of the forecast period, but I did start trending ceilings up towards the end of the period to account for this potential. Yack && .MARINE...Issued at 1258 PM CST Tue Feb 14 2023 As a surface low pressure system currently in southern Kansas matures and lifts into the Upper Mississippi River Valley tonight, south to southeasterly winds will increase with gusts of 25-30 kt and a few gale force gusts to 35 kt becoming common overnight. Winds will shift toward the southwest and increase markedly toward daybreak Wednesday with gales to 40 kt prevailing through late morning. Southwesterly to westerly winds will then fade during the afternoon. Borchardt && .LOT WATCHES/WARNINGS/ADVISORIES... IL...Wind Advisory...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011- ILZ012 until noon Wednesday. Winter Storm Watch...ILZ003-ILZ004-ILZ005-ILZ008...3 AM Thursday to 9 PM Thursday. Wind Advisory...ILZ013-ILZ019-ILZ020-ILZ021-ILZ023-ILZ032-ILZ033- ILZ039-ILZ103-ILZ104-ILZ105-ILZ106-ILZ107-ILZ108 until noon Wednesday. IN...Wind Advisory...INZ001-INZ002-INZ010-INZ011-INZ019 until noon Wednesday. LM...Gale Warning...nearshore waters until noon Wednesday. && $$ Visit us at weather.gov/chicago Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSChicago www.twitter.com/NWSChicago www.youtube.com/NWSChicago
Area Forecast Discussion
National Weather Service Memphis TN
912 PM CST Tue Feb 14 2023 ...New UPDATE... .UPDATE... Issued at 826 PM CST Tue Feb 14 2023 Showers continue to linger in portions of northeast Mississippi this evening but should clear within the next hour or two. In addition, winds this evening dropped below Wind Advisory criteria, so went ahead and canceled the Advisory for the entire Mid-South. Adjusted winds in grids to match recent observations through 15Z. Temperatures across the region are around 2 degrees below forecast, so adjusted values through the morning. Regarding the severe weather potential for Wednesday evening to Thursday morning, 00Z CAMs are trending towards higher CAPE values reaching further north and east, with all models showing 1200-1500 J/kg across the Mississippi Delta region. This is a trend to watch in subsequent runs as higher instability will likely translate to a greater chance for tornadoes and large hail. Additional monitoring of this system will occur overnight and tomorrow, with updates provided as needed. ANS && .SYNOPSIS... Issued at 157 PM CST Tue Feb 14 2023 A series of low pressure systems will move through the region bringing chances for showers and thunderstorms to the Mid-South over the next seven days. The first system will occur this afternoon through tonight. A stronger second system will affect the area Wednesday Night into Thursday bringing the potential for severe thunderstorms. High pressure will then build in for Friday into the weekend. Rain chances will return for early next week. && .DISCUSSION... (This evening through next Monday) Issued at 157 PM CST Tue Feb 14 2023 Currently, showers continue to spread into the Mid-South ahead of an upper level low pressure system that is tracking from the Central Plains into the Upper Midwest. There has been a couple of lightning strikes embedded in the bands of showers. The bigger story may be the strong southerly winds that are occurring due to the tight pressure gradient. Have seen numerous observations with sustained speeds between 25-30 MPH with higher gusts. Showers will begin to taper off from west to east this evening along with the winds as the system moves away from the area. The Wind Advisory will continue through midnight. A lull will occur through much of the day on Wednesday. Expect mild temperatures with highs reaching into the lower to mid 70s over much of the CWA. A second upper level low pressure system will move out of the Rockies into the Central Plains by Wednesday Night. At the SFC, a warm front will begin lifting northward across the Mid-South late Wednesday afternoon into Wednesday Night while a SFC low develops near the Red River Valley. The 12Z CAM model guidance had several different solutions on the exact track of the SFC low and how far north the warm front lifts. The HRRR was the most distressful outcome for the Mid-South showing 1500 J/KG of CAPE surging up the MS Delta behind the warm front and discrete supercells developing across the CWA. However, most of the other guidance showed anywhere from 500 J/KG to a 1000 J/KG. This aligned well with the GFS ensembles which showed a 90 percent probability of CAPE values of greater than 500 J/KG. Shear will be more than adequate as all the CAMS showed helicity values of at least 300 M2/S2. Mid 60 dewpoints will also surge northward into the area. As a result, there remains a Slight Risk of severe storms Wednesday Night into Thursday. However, the severe weather potential will be highly dependent on how unstable the atmosphere will be Wednesday Night and dependent on the exact track of the SFC low. With so many uncertainties, please continue to stay tuned to the latest forecast. In addition to the severe weather potential, rainfall amounts will range from 1-2 inches across the region. Many locations particularly across North Mississippi are seeing standing water and rivers at high levels. The additional rainfall will aggravate small streams and could cause rivers to rise to bankfull. Showers and thunderstorms will taper off from west to east on Thursday. High pressure will then settle into the Mid-South for the end of the week into much of the weekend. Temperatures will be chilly on Friday with highs expected to be in the lower to mid 40s. Temperatures will then begin to climb each day as the SFC high moves east and winds turn around back to the south. Rain chances will then return for early next week as the pattern becomes unsettled once again. KRM && .AVIATION... (00Z TAFS) Issued at 549 PM CST Tue Feb 14 2023 Primary aviation weather concern through the early overnight remains post-frontal surface winds and MVFR CIGs. Low level pressure gradient will relax overnight, with surface to FL020 winds likely falling below LLWS thresholds. TSRA chances will likely hold off until 03Z/16, based on the most aggressive CAM guidance (HRRR and FV3). Confidence in warm sector convection initiation is limited at best. Decided to go with a PROB30 TS mention at MEM rather than categorical or TEMPO in the last few hours of the TAF. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...KRM AVIATION...PWB
...Updated Aviation Forecast Discussion...

.DISCUSSION... Issued at 310 PM CST Tue Feb 14 2023 Key Messages: - Rain and snowmelt over frozen ground could lead to rising river levels, and possibly ice jams on the Platte, Loup and Elkhorn rivers. - Rain will change to snow in northeast Nebraska this evening. Snow combined with winds up to 50 mph and flash freezing of wet roads will lead to hazardous travel conditions especially in Knox and Cedar counties. - There is a small chance (5-10%) for a severe storm or two between 3 and 7 PM, mainly along and south of a line from Seward to Plattsmouth to Red Oak. Hail up to the size of quarters is the primary hazard. - A band of moderate to heavy snow will fall across southeast Nebraska and southwest Iowa late Wednesday through Thursday morning. 3 to 8 of snow are likely (70% chance) within the heaviest band of snow where a winter storm watch remains in effect. Late this afternoon through tonight: A vigorous mid/upper-level low over central KS as of midday will accelerate northeast through the mid-MO Valley this evening in response to the amplification of an upstream trough over the Interior West. In the low levels, a surface low will likewise develop through the area this afternoon into evening with decreasing clouds and steepening lapse rates promoting air mass destabilization across portions of southeast NE and southwest IA. To the north/northwest of the low track, latest short-term models indicate consolidation of the precipitation field into a deformation band, which will lift northeast through parts of northeast NE this evening. In regard to the strong/severe storm potential this afternoon, the air mass is destabilizing over southeast NE where breaks in the clouds have allowed temperatures to warm into the lower 50s. When coupled with dewpoints in the mid 40s and cold temperatures aloft, surface-based CAPE values are expected to increase into the 400-600 j/kg range this afternoon. Deepening cumulus clouds are being observed over Saline, Jefferson, and Gage counties as of 3 PM and latest HRRR forecasts suggest the development of widely scattered, low-topped storms from that area into far southwest IA through 6 or 7 PM. Forecast hodographs exhibit modest veering with height through the lowest 2-3 KM, supportive of some updraft rotation. Hail up to an inch in diameter is the most likely hazard with the most intense storms. The absence of a more coherent surface low and/or surface baroclinic zone (which are often sources of low-level vorticity in these low-topped storm setups) is expected to limit the potential for a more robust tornado threat. For the snow potential over northeast NE this evening, eventual amounts will be a function of how quickly colder air in the low levels spreads into the area. We will maintain similar amounts to that of the previous forecast with the best potential for 1-3" being near the SD border. The snow onset will coincide with the development of strong northwest winds behind a cold front with the potential for reduced visibilities in falling snow and slick roads due to snow accumulation and some flash-freeze potential. The strong winds mentioned above will overspread the area tonight behind a cold front with gusts of 45 to 55 mph likely over northeast NE into west-central IA where a wind advisory is in effect. Wednesday and Thursday: On the heels of today`s weather system, another shortwave trough is forecast to eject northeast into the central Plains Wednesday night, on the immediate poleward side of a strong midlevel jet streak. This will be yet another split-flow setup in the midlevels with still some model uncertainty in exactly how the central Plains system will interact with an amplifying midlevel wave over the ND-MN Red River Valley and upper-MS Valley. As a result, we see model differences in the location and strength of a frontogenetically forced snow band which is forecast to develop across the southern half of our area Wednesday afternoon into Wednesday night. While our deterministic forecast will increase snow amounts for locations along and south of I-80, the ensemble spread (as depicted by the 25th-75th percentile ranks) will reflect the large potential range, especially along the I-80 corridor. And due to that uncertainty, we will maintain the Winter Storm Watch, adding Saline, Seward, Lancaster, Cass, and Mills Counties. Regardless of where the heaviest snowfall occurs, we expect that the Thursday morning commute will be impacted due to the combination of falling snow and slippery roads. And, those conditions will be exacerbated by gusty north-northwest winds. High temperatures Wednesday will range from lower 20s over northeast NE to lower to mid 30s over southeast NE and southwest IA. Readings on Thursday will be mainly in the 20s. Friday and beyond: The large-scale pattern will favor a warming trend this weekend with cooler temperatures by early next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 557 PM CST Tue Feb 14 2023 A mix of MVFR, and IFR conditions (ceilings 500 to 3000 ft AGL and visibilities of 1 to 5 SM) will continue in the region through 18Z Wednesday. The lowest visibilities and ceilings will be focused over northeast Nebraska through 08Z Wednesday. Rain and snow will be the main hazard in northeast Nebraska (including KOFK) through 08Z Wednesday. Thunderstorms will remain a hazard for aviation in far southeast Nebraska and southwest Iowa through 03Z Wednesday. Gusty northwest winds will occur in the region through 00Z Thursday. Peak gusts of 40 to 50 kt are possible in northeast Nebraska (including OFK) between 03Z and 12Z Wednesday. Gusts over 30 kt should linger between 12Z Wednesday and 00Z Thursday. Peak gusts in southeast Nebraska and southwest Iowa (including KOMA and KLNK) should be between 30 and 40 knots through 15Z Wednesday. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Wind Advisory until 6 AM CST Wednesday for NEZ011-012-015>018- 030>034-042>045-050-051-065. Winter Storm Watch from Wednesday afternoon through Thursday morning for NEZ065>068-078-088>093. Winter Weather Advisory until 2 AM CST Wednesday for NEZ011-012- 016-017-030-031. IA...Wind Advisory until 6 AM CST Wednesday for IAZ043-055. Winter Storm Watch from Wednesday afternoon through Thursday morning for IAZ079-080-090-091. && $$ DISCUSSION...Mead AVIATION...Albright
Area Forecast Discussion
National Weather Service New York NY
945 PM EST Tue Feb 14 2023 .SYNOPSIS... High pressure moves offshore tonight. A series of warm fronts will move across the region Wednesday into Thursday, followed by a strong cold frontal passage on Friday. High pressure then builds to the south of the area for the weekend and slides offshore into early next week. Another weak frontal system approaches Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... A cirrus broken to overcast deck has moved into the region, with a few mid level clouds as well, as the upper ridge was moving off the coast and an upper shortwave was moving into the western Great Lakes. Warm advection was also increasing across the interior, and will increase overnight/toward morning across the rest of the region. With the cloud cover temperatures have responded by slowing radiational cooling, and minor rises, mainly along the coast. Some guidance is indicating temperatures may hold nearly steady or slowly rise. Updated temperatures and dew points to indicate this. And with the warm advection and increased forcing there will be a chance for a few sprinkle across Orange county toward morning, as the HRRR is now indicating, and slightly increased LAV probabilities. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... The aforementioned shortwave will lift out of the Great Lakes Wednesday and then lift into southeast Canada Wednesday night. A surface low will also be located well to our north and west on Wednesday. This system will begin to lift a warm front north through the area on Wednesday and Wednesday night. Low level warm advection will increase through the day on Wednesday with 30 to 50 kt of flow between 1 and 4 kft, strongest out east across Long Island. The main story on Wednesday will be a breezy southerly flow and unseasonably warm temperatures. Southerly gusts 25-35 mph are possible, especially over Long Island and near the coast. Temperatures will rise well into the 50s with lower 60s likely for the NYC/NJ metro. Have continued to fallow the 50-75th percentile of the NBM for highs on Wednesday given the mild synoptic pattern aloft. These temperatures are 15-20 degrees above normal for this time of year. Records for February 15 are mainly in the 70s for NYC and 60s along the coast. The record for Islip, NY is 57 set in 1984 and the current forecast is for a high of 55 degrees. If temperatures end up a few degrees warmer, than this record be tied or broken. However, this may be difficult due to the strong southerly flow off the colder ocean. Mostly cloudy conditions will otherwise start the day. There may also be a few isolated sprinkles mid to late morning, but a dry subcloud layer will prevent any measurable precip. Have left mention of sprinkles out of the forecast. Clouds from the morning will diminish from west to east in the afternoon. A mild Wednesday night is in store as anomalous ridging will remain off the eastern seaboard. A stronger shortwave continue digging across the Plains leaving SW flow both aloft and at the surface. The warm front should be lifting well north of the area with just few to scattered high clouds. The gusty winds during Wednesday will diminish Wednesday evening, but there will likely still be around 5- 10 mph of SW flow early Thursday morning. Lows look to only be in the 40s across the region. && .LONG TERM /THURSDAY THROUGH TUESDAY/... An area of low pressure moving into the Great Lakes region on Thursday, will lift northward into eastern Canada during the day Friday. An associated warm front with this system will lift northward across the region late Thursday into Thursday night, followed by a strong trailing cold front on Friday. Expect a cloudy day Thursday with the approach of the warm front along with periods of rain. A break in the precipitation is possible late Thursday evening into Thursday night as the warm front lifts north and the cold front remains west of the region. A strong low level jet increases to 45-55kt, bringing in a very moist airmass for this time of year. PWATS are forecast to increase to 1.25 inches or greater. Despite the moist airmass, the cold front is forecast to move across the region rather quickly late Thursday night into Friday morning. As a result, there should be a short period of gusty S/SW winds and heavy shower activity. Will continue to mention the potential for embedded thunder in the forecast Thursday into Friday morning. POPs quickly come to an end Friday afternoon/early evening as the front pushes eastward. As the front, exits, there remains a very low chance for snow showers to mix in with the rain just before ending. The best chances for this will be across the higher terrain north and west of NYC. A decent southwest flow ahead of the front will allow temperatures to climb into the 50s and lower 60s on Thursday. While Thursday is expected to be mostly cloudy, if any break occur (especially in the early to mid afternoon) and we get some sunshine, temperatures could be slightly warmer than forecast. For Friday, highs will be in the lower and middle 50s, however, those highs are expected to occur early in the day, and temperatures will gradually fall through the late morning and afternoon. Behind the cold front, winds veer northwest and colder air advects in late late Friday and Fri Night on gusty NW winds (30-40mph) and brings a brief return to temperatures seasonable for mid-February. The return to seasonable temps Fri Night/Sat appears short lived as general agreement for a return to zonal upper flow and high pressure building to the south of the area Sat Night into Sunday with an mild return flow developing once again. Highs on Saturday will be in the 30s and lower 40s, warming into the upper 40s and lower 50s on Sunday. For Monday and Tuesday, a weak mid level shortwave is forecast to move out of the Great Lakes region and into the northeast bringing a warm front close to the area. Precipitation chances increase through the period, but will limit POPS to chance or slight chance both days being so far out in the period. With the continued lack of cold air, ptype will be all rain and amounts look quite light at this point. High temperatures will continue to run 5-10 degrees above normal, in the low to mid 50s. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... High pressure along the coast moves slowly into the western Atlantic through Wednesday. Meanwhile, low pressure passes to the northwest during Wednesday. VFR. Light SW winds become S this evening, and light and variable at the outlying terminals. By late morning speeds at coastal and metro terminals should increase to 10-15G20kt, with occasional gusts up to 25kt. Gusts end late Wednesday afternoon with the winds beginning to veer to SW. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled amendments expected. OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY... Wednesday night...VFR. MVFR vsby possible at times E of the NYC metros late at night/toward Thursday morning. Thursday...MVFR vsby possible at times E of the NYC metros early AM. Rain developing in the afternoon with MVFR expected, IFR possible. S winds 10-15 kt in the afternoon along the coast. Thursday night...Rain showers likely and slight chance of thunder. MVFR cond expected, IFR/LIFR possible. SSW winds increasing to 10-15G20kt by midnight, and 15-20G25-30kt by daybreak. Friday...Rain showers likely especially in the morning with MVFR or lower cond in the morning, gradually improving in the afternoon. SW winds 15-20G25-30kt, becoming NW 20G30kt kt in the afternoon, then slowly diminishing late at night. Saturday...VFR. NW winds 10-15kt, becoming W in the afternoon, then diminishing at night. Sunday...VFR. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Only minor changes were made to the wind speeds over the ocean waters with the update. High pressure moving over the waters tonight will lead to conditions below SCA levels. S-SW flow increases on Wednesday and should reach SCA criteria in the afternoon and evening. Mixing will likely be limited by the warmer air moving over the colder ocean. However, surface winds will likely be around 20 kt so it will not take much for gusts to reach 25 kt. Ocean seas will also build through the day and should become 5-7 ft in the evening. Winds will diminish fairly quickly after sunset, but ocean seas may remain elevated through much of Wednesday night. An SCA has been issued on the non-ocean waters from 16z to 23z Wednesday, and 16z Wednesday - 11z Thursday on the ocean. While a brief break in the SCA conditions is forecast for Thursday, winds and seas increase back to SCA levels on the ocean waters Thursday night out ahead of an advancing cold front. S to SW winds shift to NW Fri morning with the passage of the cold front, with SCA conditions expected on all waters. These conditions are expected to continue into Friday night. There is a chance for some gale force gusts, particularly on the ocean with cold air advection. Seas on the ocean likely peak at 7 to 11 ft during this time. SCA conditions likely remain on the ocean waters through much of Saturday before winds winds begin to subside. Seas likely follow suit from west to east Saturday afternoon into Saturday evening. suit. Sub SCA conditions are likely for all waters on Sunday. && .HYDROLOGY... Around 1/4 to 1/2" of rain likely Thursday afternoon into Friday morning, with a reasonable worst case of up to an 1". No widespread hydrologic impacts are expected through the end of the week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory from 11 AM to 6 PM EST Wednesday for ANZ331-332-335-338-340-345. Small Craft Advisory from 11 AM Wednesday to 6 AM EST Thursday for ANZ350-353-355. && $$ SYNOPSIS...BC/DS NEAR TERM...BC/DS/MET SHORT TERM...DS LONG TERM...BC AVIATION...MET MARINE...BC/DS/MET HYDROLOGY...BC/DS
Area Forecast Discussion
National Weather Service Springfield MO
619 PM CST Tue Feb 14 2023 ...Updated 00Z Aviation Discussion... Key Messages: 1. Up to 40-55 mph non-thunderstorm wind gusts expected through this evening. Rain showers will exit the eastern Missouri Ozarks by late this afternoon. 2. A small batch of a few thunderstorms will clip portions of west-central Missouri between about 4 to 8 PM today 3. Thunderstorms possible later Wednesday evening into Wednesday night over far southern Missouri. A few strong to severe thunderstorms could occur, with hail up to the size of quarters as the primary hazard. 4. A light wintry mix for northwest portions of the area late Wednesday night into Thursday morning. No impacts are expected from the wintry weather. 5. Gusty northwest winds expected on Thursday, ushering in the coldest air for Friday morning with wind chills in the single digits to low teens. .SHORT TERM...(This evening through Wednesday) Issued at 256 PM CST Tue Feb 14 2023 Rest of this Afternoon and Evening: Regional radar imagery as of 3 PM shows the batch of rain showers from early today having cleared much of the area and will clear our eastern CWA by 4 PM. Mixing of higher wind gusts down to the surface with these showers has largely not occurred, with most gusts having been between 30-45 mph. However, some clearing of cloud cover is quickly working its way through southwest Missouri, with the gustier southwest winds expected to ramp back up later this afternoon into evening. Given a 60-70 knot 850 mb jet developing during this timeframe, momentum transfer down to the surface would support frequent wind gusts between 40-55 mph. Therefore, we have kept the Wind Advisory going through this evening. Winds will gradually weaken late this evening and overnight as the low level jet moves northeast of our region due to the low pressure system sliding into Minnesota and Wisconsin. Thunderstorm Potential Late this Afternoon: A small cluster of showers and storms has begun to blossom near the low pressure center over central Kansas as seen in the latest radar and satellite imagery. Hi-res model guidance (HREF and it`s member models) show this convective activity pushing northeast into portions of west-central Missouri as early as 4 PM and continuing through around 7-8PM into central Missouri. Most of these showers and storms look to remain northwest of our area, but could clip our portion of southeast Kansas and counties along/north of Highway 54 in west-central Missouri. Surface-based instability of around 250-500 j/kg and effective bulk shear around 35-50 knots would be enough to produce some isolated to scattered thunderstorms, though we do not anticipate any severe thunderstorm threat in our forecast area. The main threat from any thunderstorms would be occasional lightning. Tonight: Mainly clear skies and weakening winds are in store for tonight, with temperatures remaining mild, ranging from the mid 30s in our northwest to low 40s in our southeast. Wednesday: Strong warm air advection will be ongoing throughout the day on Wednesday due to southerly winds and mainly clear skies. A stationary front looks to set up somewhere near or just north of the I-44 corridor during the day, with the warm sector across roughly the southern half of our area. Areas south of the front should see high temperatures approach the mid 60s to low 70s, while locations north of the front generally remain in the 50s. Some retreating of this front to the south will occur during the evening as a surface low approaches southwest Missouri from Oklahoma, the exact track of the low and retreat of the front is still somewhat uncertain and will set the stage for .LONG TERM...(Wednesday Evening through Tuesday) Issued at 256 PM CST Tue Feb 14 2023 Wednesday Evening-Thursday: Some retreating of the aforementioned front to the south will occur during the evening as a surface low approaches southwest Missouri from Oklahoma. The exact track of the low and retreat of the front is still somewhat uncertain and will set the stage for where the warm sector will be when showers and storms move into the area late Wednesday evening into Wednesday night. High resolution model guidance further highlights this uncertainty, with the HRRR showing scattered thunderstorm activity as far north as the I-44 corridor, while the NAM nested model keeps thunderstorm activity completely south of our area. Right now, we are favoring a more blended approach, which would place the highest confidence in scattered thunderstorms mainly along and south of a Cassville to Hartville to Salem line. Given mid 40s to low 50s dewpoints, roughly 500-1000 J/kg of MUCAPE, and 70-80 knot bulk shear vectors, a few of these storms may become strong to marginally severe. Little to none of this instability will be surface based, so the storm hazards would be hail up to the size of quarters and frequent lightning in elevated storms. No flooding is expected due to forecast rainfall amounts remaining under 0.50 inches. Farther northwest, light precipitation on the backside of the surface low will be ongoing Wednesday night into Thursday morning, which may turn into a light rain/snow mix across areas mainly along and north of the Highway 54 corridor due to a much colder airmass pushing into the region. This precipitation should come to an end by midday Thursday. Given the preceding warm ground temperatures from Wednesday, no impacts and little to no accumulations are expected from this snow. Much colder and drier for later Thursday and Friday: Strong cold air advection will be in place for Thursday into Thursday night behind the departing low pressure system, with a sharp temperature gradient for highs across the area. Northwest winds gusting up to 35 mph on Thursday will result in high temperatures ranging from the mid/upper 30s across the western half of our CWA to mid 40s to low 50s over the eastern Ozarks where the cold air advection will be slightly more delayed. The coldest portion of the airmass will be Thursday night/early Friday morning with low temperatures in the upper teens to low 20s and wind chills as cold as the upper single digits to low teens. Friday will be cooler than average and sunny, with highs around 40-45 degrees. Next Weekend-Next Week: The weather pattern remains active for next weekend into next week, with dry weather and a sharp warming trend this weekend followed by another round of precipitation sometime during the first half of next week. While global ensemble guidance is in good agreement on a zonal flow pattern aloft for the first half of next week, confidence is much lower with regards to the track of surface lows and precipitation type/potential as a result of variance among ensemble systems. The GFS ensemble has the wettest signal for our region during this early week timeframe, while the European and Canadian ensembles are substantially drier. Have kept low end (15-30%) precipitation probabilities similar in line with the NBM on Monday and Tuesday to account for this uncertainty. Precipitation chances and confidence will very likely change in future forecast updates for this early next week system. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 540 PM CST Tue Feb 14 2023 VFR flight conditions expected through the TAF period. An area of overcast skies moves through the region this evening with clearing expected behind it. Ceilings as low as 5000 to 8000 feet with the early evening cloud cover. No additional precipitation expected at the TAF sites. Meanwhile, south/southwest winds will continue to gust through the evening at 25 to 35 knots. The strong winds will dissipate through the overnight hours. Some LLWS will also accompany a strong a low-level jet this evening. Expect LLWS of 45 to 55 knots to dissipate around 06Z. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...Wind Advisory until 3 AM CST Wednesday for MOZ055>058-066>071- 077>083-088>098-101>106. KS...Wind Advisory until 3 AM CST Wednesday for KSZ073-097-101. && $$ SHORT TERM...Rothstein LONG TERM...Rothstein AVIATION...Perez
Area Forecast Discussion
National Weather Service Shreveport LA
848 PM CST Tue Feb 14 2023 ...New UPDATE... .UPDATE... Issued at 844 PM CST Tue Feb 14 2023 Latest HRRR is starting to come around to the 18z NAM output in suggesting that low level moisture will begin returning overnight, much faster than the NBM suggested earlier. IR Imagery already showing low ceilings returning to portions of NE LA and SC AR and this will also be a favorable location for patchy dense fog to form overnight as well. Already seeing this across portions of SC AR and NE LA as well. For the update, added patchy fog to the southeast half of the forecast region for the remainder of the night and into the mid morning hours on Wednesday. Also removed precip mention for the remainder of the night. Did not touch overnight low temperatures as our northwest zones will obviously fall off more than our southeast zones given the low level moisture return will be confined to our southeast half. Updated zone package already sent...13. && .SHORT TERM... (This evening through Wednesday Night) Issued at 231 PM CST Tue Feb 14 2023 The latest RAP mid-level analysis indicates that a closed low is centered across central Kansas and is shifting northeastward toward the Upper Midwest. Ahead of this feature, a broad swath of mid-level moisture extends across the Tennessee Valley and the Missouri Valley with the back edge of this moisture exiting the ArkLaMiss. Much drier air in the mid to lower levels is now reaching the ArkLaTex and pressing northeastward. Weak vort energy related to this feature is crossing north-central Louisiana. At the surface, a 987mb low is centered over Nebraska with an occluded front southeast of this feature pushing into Missouri and Arkansas. In Arkansas, the occlusion splits into a cold front which is bisecting our area and a warm front extending eastward into the Mississippi Valley. The cold front currently extends from Union County southward to Ruston and further south to Natchitoches. Ahead of the front temperatures are close to 70 with temperatures behind it ranging from the 50s in the ArkLaTex and SE Oklahoma to the mid 60s in East Texas where sunshine has allowed temperatures to recover in the wake of the relatively weak front. Remnant scattered showers are east of a Hope-Shreveport- Lufkin line with visible satellite imagery indicating that skies are quickly clearing from the west. This evening, the upper low will quickly pull northeastward across into the Upper Midwest and the cold front will quickly slide eastward of the ArkLaMiss. As the front exits the area, a thin line of heavy rain can be expected along with a wind shift with winds gusting to 20-30 mph. Given wind gusts along the line will be brief and winds behind the line are not reaching criteria, the Wind Advisory was cancelled for portions of Deep East Texas, East Texas, and northwestern Louisiana. Otherwise, more broader synoptic scale forcing from the upper low and its associated vort max will lead to scattered showers through the afternoon before rain comes to an end this evening. Skies will continue to clear from the west, with rapid clearing in northern Louisiana and southern Arkansas late this afternoon into the evening. Tonight, the initial upper low will push into the Great Lakes while a new, stronger closed low enters the Four Corners region. This will allow the ArkLaTex to remain in a southwesterly flow ahead of this feature, allowing a reinforcement of warmer air. The lower and mid levels (1000-500mb layer) will become bone dry overnight with clear skies to start and some high cirrus spilling into the area by dawn. This will keep the forecast dry overnight. Wednesday into Wednesday night, the weather gets active again in a progressive pattern as the aforementioned closed low moves from the Four Corners area to the Central Plains. Meanwhile, a surface low will swing across the Texas panhandle on Wednesday and across Oklahoma into the Missouri Valley on Wednesday night. The low will swing another cold front with showers and thunderstorms across the region on Wednesday night. As the front clears east of the area, showers will begin come to an end behind the line during the pre-dawn hours on Thursday. This front will be noticeably stronger, bringing cooler air into the area in its wake later in the week. Ahead of the front, an unstable air mass will be in place on Wednesday afternoon with 1500-2000 J/kg of SBCAPE. Vertical shear in this environment will be strong (0-6km shear 50-60 kts). Considering the shear and instability parameters, hi-res convective allowing models (CAMs) are hinting that we could see showers start to move into central Louisiana and Deep East Texas in the early afternoon hours. As we get into the early evening hours, isolated strong to severe thunderstorms will begin in central Louisiana and Deep East Texas and then shifting northward to the I-20 corridor after sunset. By late evening, southern Arkansas will also see the severe threat. Overnight, a line of storms is expected with the front itself, bringing a damaging wind threat. The primary threats of concern right now are large hail and damaging winds, although there are is also a threat of isolated tornadoes. One limiting factor will be the loss of daytime heating, but a corridor of sufficient instability (SBCAPE 1000 J/kg) appears to be enough for severe thunderstorms to still be possible considering the strong shear in place. With all of this under consideration, the Storm Prediction Center in Norman, Oklahoma, has the area highlighted in a Slight Risk in its Day 2 Convective Outlook. Right now, flash flooding does not appear to be a threat with this event with limited coverage of rainfall and fairly fast-moving storms. For temperatures, the forecast is pretty close to the National Blend of Models (NBM). Lows tonight will range from the lower 40s in SE OK/SW AR to the mid 50s in central Louisiana. Highs will be around 15 degrees above normal across the area on Wednesday. As cooler air begins to filter in behind the front on Wednesday night, lows will range from the upper 30s in McCurtain County, OK to the upper 50s in central Louisiana and north-central Louisiana. /04-Woodrum/ && .LONG TERM... (Thursday through next Monday) Issued at 231 PM CST Tue Feb 14 2023 Seasonable and dry conditions will continue for the Four State Region through the weekend before a quick warmup arrives with the next chance of rain early next week. Lingering precipitation from Wednesday`s disturbance will gradually clear out through the rest of the day on Thursday as the frontal boundary proceeds eastward towards the lower Mississippi River Valley. By Friday, post-frontal surface ridging will maintain enough subsidence to keep conditions dry through the rest of the weekend, while clearing skies will also allow for ideal radiational cooling (with temperature minimums at or below freezing in most areas and maximums in the 50s). By early next week, southwesterly flow orientation aloft will transition into a more zonal orientation ahead of a slow-moving upper-level trough approaching the Baja California peninsula. This, in combination with a surface ridge axis shifting towards the southeast U.S., will help deliver warm air advection into the area. As a result, temperature maximums will be boosted into the 60s and 70s and minimums into the 50s (well above average for this time of the year). This atmospheric WAA setup will be favorable for the next chance of rain to occur as next week begins. /16/ && .AVIATION... (00Z TAFS) Issued at 448 PM CST Tue Feb 14 2023 Tricky forecast when it comes to aviation concerns tonight resulting in a very uncertain forecast. Showers are currently exiting our far east and southeast airspace and expect that trend to continue through the night. Low clouds in association with this exiting precipitation are pushing east as well but will they be back tonight is the million dollar question. Latest NBM guidance suggests this IFR/MVFR cloud cover will flirt with the MLU/LFK terminals overnight through much of the morning before slowly returning northward mid to late morning on Wed with ceilings scattering out. Latest 18z NAM output suggesting at least the southeast 2/3rds of our region will see a significant return of boundary layer moisture overnight such that IFR/MVFR ceilings will stop their progression eastward, returning overnight. Will play the role of the optimist with this 00z TAF package and forecast VFR conditions across all but the MLU terminal through sunrise on Wed but if IR Satellite trends prove otherwise this evening, 06z TAF package would obviously contain more cloud restrictions. Did not include any weather in this TAF package as severe weather threat appears to be very marginal through this TAF window, increasing beyond the 02/17/00z window. 13 && .PRELIMINARY POINT TEMPS/POPS... SHV 52 77 51 63 / 0 30 80 20 MLU 57 75 60 69 / 0 30 90 60 DEQ 43 74 41 53 / 0 10 90 10 TXK 50 76 47 58 / 0 20 80 10 ELD 51 75 53 63 / 0 20 90 30 TYR 50 77 43 53 / 0 30 60 10 GGG 51 77 47 58 / 0 30 70 10 LFK 51 76 51 61 / 0 30 60 20 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...04 LONG TERM....16 AVIATION...13