Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/26/24


Area Forecast Discussion
National Weather Service Hastings NE
618 PM CDT Mon Mar 25 2024 .KEY MESSAGES... - The entire Hastings forecast area remains under either a Blizzard Warning or a Winter Weather Advisory through 7AM Tuesday morning. - Additional snowfall accumulations of one to four inches are possible in addition to a light glaze of ice on surfaces. Additionally, gusty winds may result in some reductions to visibility, which will result in impacts to those traveling. - Expect a drying out period and gradual warming trend through the end of the week, with highs returning to the 50s and 60s by Friday. && .DISCUSSION... Issued at 237 PM CDT Mon Mar 25 2024 Dreary, damp and dismal conditions continue across the region today as we receive another taste of winter. The first wave of precipitation brought rain and snow to the area overnight into today. Freezing drizzle will be possible across the region, leaving the potential for a light glaze of ice on elevated surfaces. Additionally, light snow will be possible in the western portions of the area. Models such as the HRRR have been showing a second surge of precipitation moving north into the area this evening and overnight, as a closed low lifts to the northeast through the Hastings CWA. This will bring additional chances for snow to the region. QPF amounts were bumped up slightly, but may not be quite high enough to accurately depict the potential moisture. As it stands right now, an additional one to four inches of snow will be possible through the conclusion of this event. Should QPF values be on the lower side, we could receive slightly more snowfall. Thayer and Fillmore counties in Nebraska were added to the Winter Weather Advisory, with one to three inches of snow possible and a light glaze of ice on surfaces. Blizzard Warnings and Winter Weather Advisories remain in effect for the entire CWA through 7AM Tuesday morning. Some blowing snow may be possible overnight and into Tuesday morning as winds gust to over 40MPH in many areas. This is a heavier, wet, mid-March snow and not the light snow that we saw earlier in the year, so this is expected to help keep some of the blowing potential at bay. Additionally, areas in the eastern portion of the area have yet to have much snow sticking on the ground. This too would impact any chances for blowing snow tonight/tomorrow morning. Heading into Tuesday morning, northwest winds are expected to taper off through the morning as models show the closed low becoming an open wave as it lifts to the northeast, out of the region. Kept some patchy blowing snow in the region as the system moves out. Expect a drying out period and a warming trend through the end of the week. High temperatures are expected to warm into the 30s and 40s for most areas on Wednesday. Highs in the 50s and 60s are expected Thursday and Friday, with a few low 70s possible in Kansas on Friday. Low end chances (20-30%) for precipitation return to the forecast on Sunday as an upper trough is expected to move into the region. There remains considerable disagreement on timing and location of the trough moving in, so certainty is fairly low in precipitation at this point in time. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 610 PM CDT Mon Mar 25 2024 With the winter weather across the area, conditions are expected to be MVFR to IFR (possibly LIFR at times) for most of the TAF period. Expect the period to start with poor conditions with ceilings mainly MVFR, but ceilings IFR to MVFR depending on the main snow band across the area. Worse conditions are more likely at KEAR than at KGRI. This evening, snow and blowing snow across the area will continue and while ceilings are expected to remain MVFR, visibility will likely drop to IFR (perhaps LIFR at KEAR) until after midnight. As snow moves east Tuesday morning, visibility and ceilings are expected to improve, although BLSN is still expected. Skies will begin to clear late Tuesday morning and should be entirely clear by the end of the period. Winds: Winds will be north-northwesterly gusting to around 40 kts into Tuesday morning. Late Tuesday morning/Tuesday afternoon, winds will become more northwesterly and lighter, "only" gusting to 20 kts by the end of the TAF period. && .GID WATCHES/WARNINGS/ADVISORIES... NE...Winter Weather Advisory until 7 AM CDT Tuesday for NEZ041-048- 049-062>064-075>077-084>087. Blizzard Warning until 7 AM CDT Tuesday for NEZ039-040-046-047- 060-061-072>074-082-083. KS...Winter Weather Advisory until 7 AM CDT Tuesday for KSZ005>007- 017>019. && $$ DISCUSSION...Wekesser AVIATION...Hickford
Area Forecast Discussion
National Weather Service Green Bay WI
708 PM CDT Mon Mar 25 2024 Updated aviation portion for 00Z TAF issuance .KEY MESSAGES... - Mainly rain is expected through Tuesday, before changing over back to light snow late Tuesday over north-central Wisconsin. Minor snow accumulations are possible, but with little to no impacts. - Slight chance for a thunderstorms is possible over northeast Wisconsin on Tuesday. If thunderstorms develop, there is low potential for the storms to produce gusty winds to 45 mph. - Strong SE winds tonight through midday Tuesday. There is a 70-90 percent chance of wind gusts exceeding 35 mph over northeast WI toward the lakeshore. && .DISCUSSION... Issued at 247 PM CDT Mon Mar 25 2024 Short Term...Tonight and Tuesday Latest RAP analysis and radar indicate an inverted trough moving across the region and warm front lifting across southern Wisconsin this afternoon brining rain showers mainly for central and east- central WI. The rain is expected to expanded in coverage this afternoon and evening as a surface low that is currently in southeast Iowa pushes into western Wisconsin. Water vapor imagery shows a warm conveyor belt that will continue to to bring periods of heavier rain to eastern WI tonight. Additional upper-level support in the form of a left front jet quad moves over the region tonight. As the surface low lifts off to the northeast Tuesday it will drag a cold front across the region Tuesday afternoon. Thermal profiles show there will be chance for precipitation to transition back to snow late in the afternoon, but this window looks brief so not expecting much in the way of accumulations. There is a slight chance for few rumbles of thunder Tuesday late morning, mainly across eastern WI with modest 100-200 J/kg MUCAPE and mid-level lapse rates approaching 7-7.5 C/km. The chance for for any thunder diminished after the passage of the cold front. If any thunderstorms were to develop a few gusts to around 40 mph may be possible. The development of a strong low level jet of 45-50 knots tonight will bring gusty southeast winds, mainly for areas from the Fox Valley to the lakeshore. HREF probabilities show a 70-90% for gusts greater than 35 mph, and 50-60% chance for gusts greater than 45 mph tonight and early Tuesday morning. The strong southeast winds will bring warmer temperatures back into the region tonight with lows tonight only expected to drop into the mid 30s across the north to mid 40s across the Fox Valley. Temperatures tomorrow are expected to warm back into the mid 40s to mid 50s across the region. With the well above freezing temperatures and rain on the new snowpack some minor urban street flooding may be possible, mainly across central WI where the highest snow totals were. Long Term...Tuesday Night Through Monday Precipitation will be coming to an end Tuesday night as a surface low lifts north from the northwestern Great Lakes to central Ontario. Colder air rushing in from the west will change the precipitation over to snow from west to east Tuesday evening before coming to an end by midnight as drier air rushes in behind the departing low. Despite the changeover to snow, the amount of moisture in place behind the cold air is fairly meager. Therefore, snowfall amounts Tuesday evening are only expected to be a few tenths of an inch at best across central and north-central Wisconsin. The cold air rushing in will cause temperatures to fall across the region; with lows ranging from the middle teens across the north and mid 20s across east-central Wisconsin. The forecast is expected to be mainly dry from Wednesday through Friday morning as the flow flattens and becomes more zonal. Temperatures during this period will continuously warm from Wednesday through Friday, with highs well into the 40s by Friday. The pattern becomes more active Friday afternoon through early next week as a series of low pressure systems bring the chance for precipitation to the region at times. There will also be a break in the precipitation, currently from Saturday night to early Sunday, which could change in subsequent runs. Precipitation type looks to mainly be rain across central and east-central Wisconsin during this period, with some snow mixing in at times during the overnight period. Across north-central Wisconsin, a mix of rain and snow is expected with mainly snow expected during the overnight hours. Snowfall amounts during this period appear to be fairly light, with an inch or two possible given the right combination of moisture and cold air. NWP models that far out aren`t in great agreement; therefore, pinpointing more specific amounts and placement of the snow isn`t possible with this set of model runs. && .AVIATION...for 00Z TAF Issuance Issued at 705 PM CDT Mon Mar 25 2024 Poor flying conditions are expected through the TAF period as a strong cyclones moves north across central Wisconsin. A broad band of moderate rain will continue to surge northward across the forecast area through the late evening and into the early morning Tuesday. The rainband will be accompanied by IFR/LIFR conditions. Although the heaviest rainfall will likely push northeast of the forecast area toward daybreak Tuesday, continued scattered shower activity, IFR cigs and patchy light fog will persist. Southeast winds will also be strong east of the surface low overnight into early Tuesday, with a few surface gusts into the 30-35 kt range along with notable LLWS,especially east of I39 to the lakeshore. As the surface cyclones moved northward into upper Michigan late Tuesday morning, a trailing cold front, in concert with an upper- level impulse may initiate another narrow band of scattered showers, especially over eastern Wisconsin. The showers may also be accompanied by isolated thunder as well, however confidence remains low in this occurring so continued to exclude mention of thunder in this TAF package. By the end of the TAF period, winds will shift to the west and remain gusty as colder air pushes into the region. Lingering scattered -RASN showers will also be possible during the late afternoon before conditions begin to improve to MVFR by 00Z Wednesday. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....GK/Kurimski AVIATION.......ESB
Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1024 PM CDT Mon Mar 25 2024 .KEY MESSAGES... - Strong south winds will persist in central and eastern Illinois through tonight with winds gusting up to 45 mph. A Wind Advisory is in effect through midnight. - An axis of heavy rainfall will bring 1-2 inches of rain to west- central Illinois through Tuesday morning. - Isolated severe thunderstorms will be possible in eastern Illinois late Tuesday morning into early afternoon. - Below freezing temperatures are likely both Tuesday and Wednesday nights. Early-season vegetation will be susceptible to damage. && .UPDATE... Issued at 727 PM CDT Mon Mar 25 2024 Updated the forecast to remove the western handful of counties from the wind advisory, where gusts have dropped well below advisory criteria over the past couple hours. 40-48 mph gusts are still being reported from Decatur to Champaign and areas farther southeast, so will keep the advisory going for now. If gust drop here later this evening after rain moves in may end up canceling early. The steady rains have overspread the western half of the CWA early this evening, and will expand east to cover the rest of the area over the next few hours. Higher rainfall rates of 0.25"+ will occur through midnight, then begin to diminish. Additional rainfall this tonight should be around half to one inch, not creating much in the way of hydro concerns besides rises on creeks and streams, where the heaviest rain has been focused west of the IL River thus far. 25 && .DISCUSSION... Issued at 257 PM CDT Mon Mar 25 2024 Water vapor imagery shows an upper trough starting to lift north from the southern Plains states with a plume of moisture extending northward into the Great Lakes Region. At the surface, a 994 mb surface low is positioned over far northeastern Kansas with strong southerly winds in place out ahead of it. The highest winds gusts so far today have ranged from 35-45 mph, but have generally underperformed. As the low lifts into Iowa this evening, a strong ~60+ kt LLJ will nose into eastern parts of Illinois and bring another period where stronger winds can mix down mainly near/east of I-55, which has been consistently noted on both the HRRR and NAMNest. The Wind Advisory has been adjusted to remove counties in far western Illinois where winds have largely subsided, with it continuing through midnight near and east of I-55. Rain showers have become more persistent this afternoon near/west of the Illinois River. Shower activity will continue to shift eastward this evening, bringing likely rain chances to the entire area tonight. A lull in precipitation will be seen early Tuesday morning before a strong cold front works through the area later in the morning, bringing another round of scattered showers and even some thunderstorms. Although instability won`t be overly impressive (a few hundred J/kg), very strong wind shear could support a couple organized low-topped storms late Tuesday morning into early afternoon. Primary hazards with any of these storms would be damaging wind gusts, though a brief tornado or two may spin up since LCLs will be rather low. There still remain discrepancies on where storms will initiate with CAMs split between just west or just east of the IL/IN state line. The SPC day 2/Tuesday outlook still highlights a marginal risk for severe storms in eastern Illinois. Precipitation totals through Tuesday morning will range from 0.50 to 1.5 inches with the highest amounts near/west of the Illinois River. The 25.12Z HREF shows some locally higher amounts closer to 2 inches in this same area due to training. The flooding threat looks pretty marginal due to recent dry conditions, though some ponding of water in low lying spots could result. 6 hour flash flood guidance is between 2.5 and 3 inches areawide, so the threat for flash flooding will be very low. Ensemble guidance (ENS, GEFS, GEPS) only show a 5- 10% chance of 2.5+ inches of rain near/west of the Illinois River. Surface ridging settles into the area by the middle of the week as the upper trough shifts into the eastern CONUS, bringing a period of cooler temperatures back to the area. Overnight lows Tuesday and Wednesday nights will fall below freezing and pose a threat to early season vegetation. Upper ridging builds over the central CONUS by the end of the week, with southerly return flow setting up locally. Temperatures will gradually climb to near normal values on Thursday, and then climb well above normal for the end of the week into the weekend. Our next chances for precipitation arrive late Friday night into this weekend as a few upper shortwaves round the top of the upper ridge. NMA && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1024 PM CDT Mon Mar 25 2024 A band of moderate rain will diminish over the next few hours, leaving MVFR ceilings across the central IL terminals overnight. While some breaks will occur at times, predominant MVFR ceilings are forecast for this TAF cycle. After the main area of rain exits, isolated showers will persist until a cold front pushes through between 12-17z, and mentioned VCSH for this. Southeast winds gusting around 25 kt tonight will veer southwest Tuesday morning, gusting 25-35 kt through afternoon. 25 && .ILX WATCHES/WARNINGS/ADVISORIES... Wind Advisory until midnight CDT tonight for ILZ044>046-053>057- 061>063-066>068-071>073. && $$
Area Forecast Discussion
National Weather Service North Platte NE
647 PM CDT Mon Mar 25 2024 .KEY MESSAGES... - A new area of light snow is underway across swrn Nebraska and this snow will spread through ncntl Nebraska this evening. Around 2 inches of snow is forecast overnight before it exits the area before sunrise Tuesday. - Blizzard warnings continue tonight across ncntl Nebraska where wind gusts of 45 to 55 mph are predicted. Wind speeds will subside throughout the evening and overnight. - A Winter Weather advisory is in place this evening for areas along highway 83. Snowfall amounts of up to 2 inches are possible across areas east of highway 83. && .SHORT TERM /THROUGH TUESDAY NIGHT/... Issued at 325 PM CDT Mon Mar 25 2024 The RAP model is the basis for the snow forecast tonight. The model suggests 1 to 3 inches across ncntl Nebraska with little or no snow along and west of highway 83. The wind forecast uses the short term model blend plus bias correction plus 1 to 2 kts markup to line up with the 500m AGL winds of 20 to 30 kts. The wind gust tool suggested gusts of 35 to 45 mph east of highway 83. The Blizzard Warning across ncntl Nebraska can continue in place. A Winter Weather advisory is in place for the row of counties just to the west, or along highway 83 until 06z tonight. Radar and the RAP model show an h700mb low near KDDC which will lift northeast through ern KS overnight. This low and the ongoing low across nrn IA/srn MN will form a double barrel low. If the model is correct, a new area of light snow should spread into ncntl Nebraska this evening and then exit east by 10z Tuesday morning. The RAP model shows and area of modest moisture transport across cntl Nebraska drifting slowly east overnight. To the west, dry air will move in with h850-300mb RH falling to around 40 percent across wrn Nebraska by morning. This should produce mostly clear skies along and west of highway 83 by morning. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Issued at 325 PM CDT Mon Mar 25 2024 When temperatures are 30 degrees below average, there is really no where to go but up and that is what the models show Wednesday through Sunday. H850mb temperatures will warm from -10C to +10C. The warm air should be in place Thursday; Wednesday will be a transition day. The forecast respects the snow cover east of highway 83 Thursday with just 40s and lower 50s for highs; upper 50s and 60s in place west of the highway where less snow occurred. A backdoor cold front will drop through wrn/ncntl Nebraska Friday and rain chances are in place Saturday and Sunday. The rain chances appear to be focused along a stationary front across nrn Nebraska or srn SD and the upper level support is the nrn stream. An upper level low off the West coast will support moisture aloft. The setup looks reasonable but location at this range makes the forecast uncertain. The blended forecast leans on the ECM which is south of the GFS. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 646 PM CDT Mon Mar 25 2024 Snow will continue across portions of north central Nebraska through early Tuesday morning. Strong northwest winds will also continue through much of Tuesday morning before diminishing during the afternoon. Gusts up to 35 knots will create areas of blowing and drifting snow as well as visibility restrictions. Skies begin to clear Tuesday afternoon with ceilings rising back into VFR conditions. && .LBF WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 1 AM CDT Tuesday for NEZ005-025- 037-059-071. Blizzard Warning until 1 AM CDT Tuesday for NEZ006-008-009-026. Blizzard Warning until 7 AM CDT Tuesday for NEZ007-010-027>029- 038. && $$ SHORT TERM...CDC LONG TERM...CDC AVIATION...Kulik
Area Forecast Discussion
National Weather Service Paducah KY
826 PM CDT Mon Mar 25 2024 .KEY MESSAGES... - Gusty winds continue through tonight. Gusts of 40-50 mph possible with a few locally higher gusts possible. - Showers and storms spread across the area later this afternoon and tonight. - Cooler than average temps Tuesday night through Wednesday night then a warming trend Thursday onward. && .UPDATE... Issued at 826 PM CDT Mon Mar 25 2024 The HiRes Planview data was way overdone for this evening. Model soundings were much better showing the unfolding scenario, which was a saturation of the low levels fairly quickly coupled with the presence of an inversion in time. Currently, no sites are gusting to Wind Advisory criteria of 40 mph. The forecast soundings show that will remain the case through the overnight. Will eliminate the Wind Advisory from west to east with the passage of the narrow band of heavy showers moving through the region. Most of SEMO has been cleared already. Should be out of the woods across the KY Pennyrile region by Midnight CDT or so. && .DISCUSSION... Issued at 251 PM CDT Mon Mar 25 2024 A large upper level system is moving through the Central Plains and the Midwest today and tomorrow. The sfc low is moving through KS and into IA with a cold front draping south. Ahead of this system we are seeing strong, gusty winds with gusts of 40-50 mph possible through tonight. Showers and storms are expected to spread from west to east across the area later this afternoon through tonight. Rainfall totals are expected to range from around a half inch in the Evansville Tri-State area to 1-1.5 inches further west, in SEMO. The cold front is expected to pass through the area west to east tonight into tomorrow. Tomorrow winds are expected to still be breezy though not nearly as strong as today with gusts of 20-30 mph. During the morning, showers and storms will linger generally over the Evansville Tri-State. A few of these storms could be strong to severe given 100-200 J/kg of MUCAPE (the HRRR supports around 300 J/kg of SBCAPE) and rather strong 0-6 km shear nearing an impressive 100 kts. The main threats would be damaging winds and hail. SPC has a marginal risk for tomorrow and the main concerns would be mostly during the morning to maybe the early afternoon depending on when the front comes through. Wednesday sfc high pressure builds in from the west as we remain in southwest flow aloft due to broad troughing over the central CONUS. Below normal temps are expected tomorrow night through Wednesday night with several spots seeing lows around freezing. A warming trend is in store for Thursday onward though. Broad ridging aloft will move over the central CONUS by Friday. Highs return to the 70s Friday onward with highs in the upper 70s to possible low 80s on Monday. A mid level shortwave along with a sfc warm front just to our north could bring a few showers to the area Friday night and Saturday night. && .AVIATION /00z TAFS THROUGH 00Z WEDNESDAY/... Issued at 526 PM CDT Mon Mar 25 2024 Will continue with the chance of showers and strong SE winds through the evening hours as a front moves into the area. Will maintain our LLWS as low level winds increase this evening especially over west KY into southwest IN and the southern tip of IL. From west to east after 06z, winds will become more SSW, decrease for a short time, then pick up from the SW 15 to 25 KTS for Tuesday. Occasional MVFR to IFR conditions are anticipated this evening, persisting through 06-09Z. Conditions should return to VFR Tuesday. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...Wind Advisory until 5 AM CDT Tuesday for ILZ075>078-080>094. MO...Wind Advisory until 5 AM CDT Tuesday for MOZ111-112-114. IN...Wind Advisory until 5 AM CDT /6 AM EDT/ Tuesday for INZ081-082- 085>088. KY...Wind Advisory until 5 AM CDT Tuesday for KYZ001>022. && $$ UPDATE...CN DISCUSSION...SHAWKEY AVIATION...CN
Area Forecast Discussion
National Weather Service Pueblo CO
547 PM MDT Mon Mar 25 2024 .KEY MESSAGES... - Snow fades away to flurries this evening over the mountains, only some spotty, light (1-2 inch) additional accumulations expected - Snow showers (maybe a brief thunderstorm) redevelop over the mountains Tuesday afternoon, with a mix of rain and snow showers at lower elevations. Only light (1-2 inch) accumulations expected over mainly the higher peaks - Warming and drying trend through late week with increasing winds. - Another storm system possible Late Sunday through Tue of next week though details still prone to change this far out. && .UPDATE... Issued at 545 PM MDT Mon Mar 25 2024 Updated the forecast grids with the expiration of remaining winter weather highlights. Intermittent light snow showers will likely continue across the Sangres and Wets this evening, but significant additional snow accumulation is not anticipated. && .SHORT TERM /THROUGH TUESDAY/... Issued at 238 PM MDT Mon Mar 25 2024 Snow quickly fading away this afternoon, with webcams, obs and radar showing rapidly improving visibility and road conditions at most locations. Have seen some redevelopment on MRMS back over the ern San Juans and wrn San Luis Valley, and HRRR suggests this activity spreads eastward over the Valley into the Sangres late this afternoon into early evening, so will keep highlights going for the Sangres/Wets/ern San Juans until 6 pm or so. Activity should fade to flurries fairly quickly after sunset, and with clearing skies, overnight min temps will fall off into the teens and 20s at many locations. On Tuesday, last piece of upper energy rotates across, and with rather steep lapse rates, suspect we`ll see a plentiful crop of afternoon snow showers over the high terrain, with a mix of rain and snow at lower elevations. May even see a thunderstorm or 2 as well, especially if we can realize at least some partial clearing from late morning into early afternoon. Prior to convection, should be enough sun to boost temps above freezing over all but the higher mountain zones, and a few non-snow covered spots on the plains could approach 50f. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... Issued at 238 PM MDT Mon Mar 25 2024 Unsettled weather will continue through Tuesday as weaker waves in NW flow act on instability to generate some mountain showers which will spread off into the adjacent plains and valleys Tuesday evening. Any additional precipitation looks light at this point (additional 1-3 inches mainly over the mountains) and clears out by Wednesday morning. Upper ridge transitions in during the day Wednesday which will bring about the start of a warming and drying trend, especially for the lower elevations. A passing shortwave will bring a return of snow showers to the Continental Divide Thu Night/Friday but precipitation looks light at this point. However as upper flow aloft transitions to a more southwesterly component, breezy west winds will spread into the lower elevations with spotty critical fire weather conditions possible along the western and eastern fringe of the lee side surface trough. Areas to watch will be the southern I-25 corridor south of Pueblo and the far southeast plains of Baca, Las Animas, Otero, Bent and Prowers counties, especially Sat and Sunday with some near critical conditions possible as early as Thursday and Friday. The next storm system will approach the region on Sunday with Monday and Tuesday of next week carrying the greatest potential for widespread mountain snows and a rain/snow mix for the plains. There are still considerable differences in the long range models to work out, with GFS and Canadian keeping the closed low across the Desert Southwest through Tue...while 00z EC shifts it into the southern plains by 00z Wed. GEFS is more progressive like the EC with a faster timing. No changes planned from National Model Blends at this point given this is a day 8 and beyond event...but it will be the next storm system in the que to monitor. -KT && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 238 PM MDT Mon Mar 25 2024 At KALS, still a threat of some brief MVFR snow showers until 03z, then VFR cigs expected overnight into Tuesday morning. After 18z Tue, vcsh likely as mountain snow showers move across the Valley during the afternoon. At KCOS and KPUB, VFR cigs into early evening should scatter overnight, while gusty north winds continue to diminish. On Tue, VFR conditions with a vcsh after 20z as mountain showers drift eastward onto the plains. && .PUB WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...MOORE SHORT TERM...PETERSEN LONG TERM...TORGERSON AVIATION...PETERSEN
Area Forecast Discussion
National Weather Service Raleigh NC
850 PM EDT Mon Mar 25 2024 .SYNOPSIS... Cold high pressure will extend southward through the region through Tuesday. An area of low pressure will lift northeast along the Southeast US coast on Wednesday, then continue along the Carolina coast Wednesday night and Thursday. A cold front will move eastward through central NC Thursday night. && .NEAR TERM /TONIGHT THROUGH TUESDAY/... As of 850 PM Monday... The primary change with the evening update was to tweak hourly and overnight minimum temperatures. Did go a touch colder in some locations, particularly along the VA/NC border, and added patchy frost in a few locations. Considered the possibility of issuing a frost advisory for some counties along the state border, but after collaborating with neighbors, did not feel that there was enough of a widespread threat for frost, plus the temperatures below 36 degrees should only occur for a limited time. Previous discussion follows. As of 252 PM Monday... Through tonight: Light nely flow continues this afternoon with some upstream cirrus moving in from the west. Expect this cloud cover to gradually thicken overnight. Low-level thicknesses will rise some compared to this morning allowing a bit milder lows in the mid to upper 30s. Given this, and perhaps a little residual stirring tonight, the ambient weather conditions should preclude any widespread frost. Tuesday: Flow aloft will turn more swly Tuesday as an upper trough over the central US eases eastward. At the sfc, central NC will remain wedged between an offshore low to the east, a retreating high to the north, and an approaching cold front well to the west. Residual dryness will prevail through much of Tuesday, but dew points will start to recover some under esely sfc flow. Despite decent cloud cover, expect a mild day with highs in the mid to upper 60s. Weak vorticity lobes out ahead of the main upper trough will approach the southern Appalachians Tuesday afternoon and evening. Associated rain chances, however, will largely hold off for our area until after 00Z Wednesday as the deeper moisture arrives later Tuesday evening. Still, can`t rule out at least some light isentropic-driven rain in the Triad late Tuesday afternoon. Any observations will mostly read trace. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 330 PM Monday... Confidence is high in a somewhat prolonged and briefly moderate to heavy rainfall event during this period, as the expansive upper level trough extending from Saskatchewan/Manitoba to N Mexico (with embedded waves) lumbers eastward through central NOAM through early Wed and into E NOAM by late Thu. PW begins to ramp up above normal late Tue, peaking at 150-200% of normal over our area (approaching daily record maxes) and E NC Wed afternoon through early Thu before the anomalously high values gradually shifts E. Confidence is fairly high on the timing and placement of rainfall with this event, and is moderate regarding amounts, as some degree of model variability regarding amounts remains. Potential reasonable alternate scenarios for this event include slightly earlier or later rain arrival, likely not more than 6-9 hours in either direction. The LREF 25th and 75th percentiles for storm total amounts differ by 1-2", so the uncertainty there is still fairly high. The overall rainfall timing, based on the latest operational models and ensemble solutions including the LREF, is to bring chance pops to the W mainly after midnight Tue night, followed by the heaviest and most expansive rain Wed afternoon through Thu morning with likely to categorical pops, followed by a WSW to ENE taper to no pops after midnight Thu night. The heavier rain window late Wed through Wed night will coincide with passage of an upper divergence max and the approach of a strong shortwave trough pivoting through AL/GA toward the Carolinas, becoming negatively tilted in the process. This will coincide with likely multiple surface lows along the front which track through the central and eastern Carolinas. Regarding storm total rainfall, the model consensus, including the NBM, LREF, and WPC superensemble output, support values just slightly under the previous forecast, still a range of 1.5-3.25" over central NC. Given that there is expected to be very little in the way of convective elements to this rainfall ( and the fact that it will be spread out over 36+ hours in most spots, the excessive rainfall outlook is maintained this afternoon at a marginal risk. But if total values ramp up in later forecasts, esp heavier rain over a shorter time of just a few hours, an upgrade may be needed. At this time, we could see considerable minor urban flooding esp in poor drainage areas, with an uptick in river levels across the board, but there is uncertainty of any situation more dire than that occurring. Expect lows 41-54 Tue night, highs 56-71 Wed, lows 45-55 Wed night, highs 53-64 Thu, and lows 36-43 Thu night with clearing skies. Given the complexity of the expected surface pattern, confidence in the details of these temps is not high. -GIH && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 215 PM Monday... Surface high pressure over MS/AL on Friday, will shift south over Florida by Saturday. A few disturbances are expected to move over the OH valley and then over the Mid-Atlantic late Sunday into Monday. Easter Sunday is expected to be dry across the majority of the region. However, some models do show precipitation to along the VA/NC border late Sunday/Sunday night. For now have introduced minimal slight chance PoPs in portions of the Northern Piedmont near the VA border. High temperatures are expected to be above average over the weekend with highs in the low to mid 70s, with some areas in the south could near 80 on Sunday. Lows will generally be in the upper 40s to low/mid 50s. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... As of 740 PM Monday... VFR conditions will continue across much of central NC through the next 24 hours. The only possible exception is the northern and central Coastal Plain (including RWI), where some guidance continues to show potential for MVFR ceilings moving in tomorrow morning. The timing has trended slower, so now have a TEMPO group at RWI for this potential from 12z to 16z tomorrow. The HRRR model even shows IFR ceilings, but this is not supported by any other guidance, so am not including it in the RWI TAF at this time. Elsewhere, just a blanket of high cirrus will continue to spread in from west to east overnight. Lower cloud ceilings may begin to move into the west (including INT and GSO) tomorrow, but they should remain VFR through the end of the TAF period. Winds will be light and from the E/NE tonight, then E/SE tomorrow. Outlook: Rain showers and sub-VFR conditions then appear likely Tuesday night into Thursday as a strong system moves through. VFR conditions will return from west to east late Thursday into Thursday night and last into Saturday. Gusty N then NW winds will be possible on Thursday and Friday afternoons. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...KC NEAR TERM...Green/Luchetti SHORT TERM...Hartfield LONG TERM...CA AVIATION...Danco/Luchetti
Area Forecast Discussion
National Weather Service Reno NV
314 PM PDT Mon Mar 25 2024 .SYNOPSIS... The region sees a warming trend beginning the week followed by an impactful weather system that begins in the latter half of Wednesday and lasts into Thursday. The Sierra Mountain portion of the region looks to bring about stronger winds and increased accumulating snow chances with this system that may cause hazardous travel conditions. A potential second impactful weather system for the region is also anticipated for Friday that looks to last into the Easter holiday weekend. && .DISCUSSION... The latest RAP analysis shows a northwesterly flow over the CWA as the CWA is between an upper air ridge to the west and an upper air trough to the east this afternoon. Going through the day, forecast models do show an upper air shortwave passing by the northern portion of the CWA this evening which will allow around a 20-40% chance of some isolated light showers for areas along and north of a line from Eagle Lake, CA to Walker Lake, NV beginning this evening and going through the night into tomorrow. Model guidance then depicts the upper air ridge progressing eastward during Tuesday with its axis passing over the CWA on Wednesday morning. This ridge setup will allow for daytime temperatures to warm a bit on Tuesday and Wednesday along with dry conditions for Tuesday and the beginning of Wednesday within the region. On Wednesday afternoon, models show an upper air low moving towards the coast of the Pacific Northwest turning the upper air flow to southwesterly by the late afternoon/evening hours as a result. Due to this upper air setup, models show a cold front associated with a surface low off of the coast of WA making its way across the CWA bringing some stronger winds and wintry precipitation with it to the region through the night into Thursday. Latest NBM probabilities show around 50-60% probability of greater than 6 inches of snowfall within 24 hours for the Sierra ridgetops in the far western portions of the CWA along with a 10-20% chance for greater than 12 inches of snowfall in the same location. Higher elevation portions of Mono County and the Tahoe Basin not included in the previously mentioned area look to have around a 50-60% probability for 2 inches of snowfall or greater in 24 hours. The precipitation type for lower elevation portions of the CWA looks to be mostly rain with perhaps some light snow mixed in overnight though no snowfall accumulation is expected at this time. As for wind gust probabilities, valley gusts look to have around a 70-90% probability of 34 kts or greater while Sierra ridge gusts have a 60-70% probability of 48 kts or greater. Higher elevations of Mt. Rose see around a 70-80% chance of greater than 56 kts with some models. Currently, the forecast calls for Sierra Ridges gusts ranging around 60-70 kts late Wednesday. With these expected winds and snow chances, hazardous traveling conditions in the Sierra Ridge are possible especially due to potential blowing snow late Wednesday and going into early Thursday. Please watch for forecast updates as they become available as a Winter Weather Advisory may be needed. A Lake Wind Advisory might also be needed for Pyramid and Tahoe Lakes as well if future model runs continue the higher wind trend. By Thursday afternoon, precipitation chances look to taper off for most of the region though remaining around 10-20% within the Sierra Mountain portions through the rest of the day. For Friday and going into the holiday weekend, model ensembles show the upper air low traveling southward just off the Pacific Coast on Friday until it is west of central CA when it cuts off more from the general upper air flow. Model guidance then has this low begin to travel eastward across southern CA on Sunday though there is a timing discrepancy seen between long term models with this progress. While details remain uncertain, there looks to be a second impactful system affecting the region on Friday, Saturday, and potentially a portion of Sunday. More rounds of gusty winds, mountain snow, and valley rain may be on tap for the region, so again please watch for forecast updates especially those with holiday plans this weekend. -078 && .AVIATION... VFR conditions are expected for most TAF sites within the region throughout the rest of today and going into Tuesday. Models show winds gusting up to between 20 to 30 kts through the remainder of the afternoon before slowing down in the evening. The exception to the VFR statement looks to be at KTRK as freezing fog may develop in the evening near the terminal around 03Z Tuesday and last until around 17Z causing sub-VFR visibilities. KRNO, KCXP, and KTVL may also see some brief showers in the vicinity this evening though they are not expected to affect flight restrictions at this time. -078 && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$
Area Forecast Discussion
National Weather Service Topeka KS
834 PM CDT Mon Mar 25 2024 .KEY MESSAGES... -A few storms are developing in far eastern KS this afternoon. Small hail and lightning are the main concerns with storms. -A wintry mix is possible late this evening and tonight as colder air filters into the area, causing minor accumulations of ice and snow. -A widespread hard freeze will occur early Wednesday morning. -Much warmer weather returns late this week. && .UPDATE... Issued at 834 PM CDT Mon Mar 25 2024 A band of snow has been slow to move over western Republic county and there is a report of 4 inches already on the ground in courtland. Models show this band weakening with time and the thinking is amounts like this in Courtland are more likely to be the exception rather than the rule. Plan to keep the advisory going for now and watch how the band evolves with time with the potential that it may need to be expanded east a county or two. Will also bump up snow amounts across north central KS. && .DISCUSSION... Issued at 254 PM CDT Mon Mar 25 2024 At 19Z (2:00 PM) today, surface low pressure was located over far northeast KS with a cold front trailing to the south-southwest. The upper low was displaced further west, over western KS. Minor amounts of instability have developed in the warm sector environment ahead of the surface boundary with mesoanalysis showing around 300 J/kg of SBCAPE. Most CAMs were showing thunderstorm initiation ahead of the boundary in far eastern and northeastern KS after 21/22Z. However, recent radar trends have storms developing a little sooner. Small hail could occur with the stronger storms and there`s at least a slight chance for a funnel cloud in extreme northeast KS. Storms should quickly exit the area to the east late this afternoon/early this evening. Attention then turns to winter weather occurring in the colder post- frontal air as lift with the upper low moves over the area. Forecast soundings from the RAP and HRRR show saturation through the DGZ for a few hours this evening and tonight. The thinking is that a brief mix of wintry precipitation could occur in the transition to colder air, with a few hours of snow to follow. Freezing drizzle could also develop as moisture decreases aloft. However, forecast soundings also show a layer of drier air in the lowest 1,000 ft at that time, leading to uncertainty in drizzle occurring. Snow accumulations of around an inch look most likely in far north-central KS where a Winter Weather Advisory has been issued until 4 AM tonight. Other locations could see minor accumulations, but uncertainty in exact amounts remains low, in part due to warm ground temps. Low pressure quickly advances into the Upper Midwest by midday tomorrow as high pressure and drier air move into the area from the north. Temperatures will be quite chilly, struggling to warm into the 40s Tuesday. Wind chills will be in the 30s at best due to breezy northwest winds. A widespread hard freeze is then expected Tuesday night with temps falling into the low 20s to teens early Wednesday morning. Freeze headlines will be considered for the southeastern portion of the CWA where the growing season is more underway. A warming trend then commences midweek with southerly flow returning. Highs should be back into the 70s by Friday. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 536 PM CDT Mon Mar 25 2024 Cold front passes through the terminals this evening with restricted CIGS and VSBY tonight. Models are in good agreement and will use the CAM consensus in timing wintry precip at the terminals. This should be short lived with minor accumulations, but there are already reports of -FZDZ before snow begins. Conditions are expected to improve through the day Tuesday as strong northwest winds advect in drier air. && .TOP WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 4 AM CDT Tuesday for KSZ008- KSZ020-KSZ034. && $$ UPDATE...Wolters DISCUSSION...Teefey AVIATION...Wolters