Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/23/22

Area Forecast Discussion
National Weather Service Boston/Norton MA
1023 PM EST Thu Dec 22 2022 .SYNOPSIS... A high impact storm brings multiple hazards, including high winds, coastal flooding, and heavy rainfall tonight into Friday, followed by plummeting temperatures Friday evening. A chilly holiday weekend ahead, while majority of the region remains dry, areas along the immediate south coast, Cape Cod, and Islands likely to see ocean-effect snow showers Saturday, and possibly Sunday. Looking ahead to next week, dry with temperatures moderating to near average. && .NEAR TERM /THROUGH FRIDAY/... Mainly tweaked the forecast tor reflect observed trends this evening, especially temperatures and rainfall timing. Will continue to monitor timing of winds across southern New England, and transition to rainfall across the Berkshires. 630 PM update... Forecast is unfolding as expected so far, on the front end of this prolonged storm system. Radar shows returns having overspread most all of southern New England, with snow being reported in the Worcester Hills and Berkshires as of 6PM. Previous Discussion... Synoptic pattern remains little changed tonight through Fri, as a powerful primary low pressure area with associated well developed 500 mb cyclone pinwheels and occludes tonight into Fri across the Gt Lakes, which will swing a powerful cold front through Southern New England Fri aftn. This system will bring a multitude of potential hazards tonight into Friday. Each of these hazards will be touched upon in turn, described below roughly in order of timing: -- Winter Weather -- While precipitation begins as all rain, temps will be marginally cold enough at onset to begin as light accumulating snow across the eastern slopes of the Berkshires. Winter Weather Advisory for the eastern slopes of the Berkshires was maintained for tonight thru early Fri AM. However current temps in an area from Blandford to Rowe are marginal at around 30 to 32 degrees, and with temperatures standing to rise in a non-diurnal fashion, snow amounts were reduced in the Advisory area. Think the risk for accumulating snow will probably cease before the Advisory expiration due to the rising temps and this is also the indication in the latest HREF hourly p-type guidance. 2 to 4 inches of new snow should be common in the east slopes of the Berks where the Advisory is in effect with local amts up to 5 inches possible. Warming temperatures however will likely melt whatever snow develops (as well as some additional melt where snowpack existed previously in these same areas, to be discussed below). -- Strong to Potentially Damaging Winds (Main Storm Impact) -- 12z guidance today reflected no major change to the forecast and/or messaging regarding strong to damaging wind gusts. Thus no changes were made to high wind warning/wind advisory areas either in space or in valid times. SE winds will continue tonight, steadily increasing in sustained wind speed and gust magnitude. Period of strongest SE wind gusts early Fri morning to early aftn, associated with passage of a 65-80 kt 925 mb SE jet in conjunction with a strong to extreme isallobaric pressure fall-to-rise couplet tied to the strong cold front. The strongest wind gusts are still anticipated across RI and eastern/southeast MA where local gusts could be as much as 65 mph; further inland more removed from the stronger jet, peak gusts up to 50 mph. Upon passage of the strong cold front Fri aftn, winds will shift abruptly to SW; intense cold air advection will steepen lapse rates considerably and lead to more frequent albeit somewhat lower gust speeds to around 45-55 mph through remainder the aftn. Nonetheless the potential exists for wind-related damage, with possible power outages. -- Heavy Rain, Possible T-Storms and Flooding Potential -- Rain is already near our southern coastal waters associated with warm front. Other than early tonight in the Berkshires, rain will continue to advance and become steady tonight into the overnight. Locally heavy rain is possible by early Fri AM. Combination of strong mid to upper level divergence, surge in PWAT values to near or just over 1 inch, along with some elevated instability above the frontal inversion (showalter indices 0 to -1) could favor a period of at least heavy downpours Fri AM with a lower probability risk for thunderstorms across eastern MA and RI. HREF calibrated 1-hourly thunder progs show some t-storm chances between 12-16z. Rain comes to an end rapidly by Fri aftn. Storm total rainfall around 1 to 2 inches, with 2-3 inches possible in the upslope-enhanced areas in the eastern slopes of the Berkshires and Litchfield Hills. Possibility exists for urban and poor drainage hydrologic problems Fri. While generally modest rises are anticipated on most rivers, the combination of rainfall and added water due to snowmelt along creeks, rivers and tributaries along the Connecticut and Merrimack basins. See latest river forecasts from the NERFC for more information. -- Rapid Temperature Drop Fri Aftn -- Heavily utilized a mix of the HRRR and the NAM-3km for temperatures. For tonight, expect non-diurnal temperature trends with early lows in the 30s to low 40s, with temperatures rising into the mid 40s to mid 50s by daybreak Fri. Temperatures may rise a few degrees more into the morning on Fri with highs in the mid to upper 50s. But the real notable change will be the rapid fall in hourly temperatures as the potent cold front surges through Southern New England. And this is from the surge of modified Arctic air which is surging through much of the central part of the nation currently. While we are not expecting anything as extreme as the temperature falls experienced in those areas, significant hourly temperature falls with rapid drying remain anticipated once the front clears our area starting Fri Aftn. By sundown, temps will have fallen into the mid to upper 20s west of Worcester, around freezing from central MA into western RI, and upper 30s to low 40s eastern MA and RI. The combo of continued gusty WSW winds and rapid post-frontal drying should enhance evaporative potential and mitigate significant flash freeze issues across interior New England. However icy spots could still be possible. -- Coastal Flooding -- See the coastal flooding section for more detail. && .SHORT TERM /FRIDAY NIGHT/... 400 PM Update: Similar to Fri aftn, temps were heavily based on the 12z NAM-3km to better show the rapid fall in hourly temps, versus a model- blended approach. Because the very cold air mass is extremely dry and that winds will still be quite gusty from the W, that should help enhance evaporation; icy spots possible in shaded areas but we`re not looking at a flash freeze attm despite the falling temps. Lows range upper single digits to the upper teens, around low 20s Cape and Islands. Sub-zero wind chills anticipated in western/central MA and northern CT by Christmas Eve morning, with values around 10 below across the Berkshires. If wind speeds stay stronger for a longer period of time (viewed as unlikely), potential for wind chill advisories exists for the eastern slopes of the Berkshires but too uncertain attm. Also looking at a rare WSW wind-driven ocean effect snow shower scenario in the southern waters Fri night, given the much colder air and the relatively mild ocean waters. Have snow amounts up to a couple inches in the Islands with a coating across Cape Cod. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Highlights... * Gusty winds linger through Saturday * Dry and chilly through Christmas, then remaining dry with moderating temperatures next week. Details... Saturday starts out quite chilly (in the single digits and teens) compared to 24 hours before (30s and 40s). What will make conditions even more harsh will be lingering gusty winds on cold SW flow. This cold advection pattern makes for a very well mixed boundary layer, efficiently mixing down gusts of 30 to 40 mph from a 30 to 45 kt 925 mb jet. Wind chills will be in the single digits and teens on Saturday afternoon, and things remain dry for the vast majority of the area. The only exception will be for portions of Cape Cod (especially the southern coast) and the islands where the SW trajectory of the wind may direct light ocean effect snow showers overhead Saturday into early Sunday. Anywhere from a dusting further north to an inch or two further south toward Nantucket is possible. Sunday the low lifts further into northern Quebec and the pressure gradient relaxes, allowing winds to finally diminish appreciably. Christmas Day will be quiet and dry, with plenty of sun under approaching high pressure. As we move into the week between Christmas and New Years` we`re looking at more of the same with dry and quiet weather beneath a sprawling area of high pressure that builds in from the south and east. The main change of note will be slowly moderating temperatures, into the 30s and even 40s by Thursday. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Tonight: High confidence in trends, moderate on timing. Deterioration all sites this period with MVFR-IFR ceilings, advancing precip (largely -RA/RA, but higher elev -SN thru 06z in the Berkshires and northern hills in Worcester County), and increased E/SE gusts. Winds increase to become ESE sustained 15-25 kt/gusts 35-45 kt with areas of low-level shear/turbulence. Friday: High confidence in trends, moderate on timing. **Significant aviation impacts probable this period.** Through the morning...IFR-possible LIFR ceilings with VFR/MVFR with steady rain, some heavy at times (low prob T/TS eastern/southeast airports 12-16z). Strong SE winds, gusts 40-50 kt strongest eastern/southeast MA and the Cape. Areas of LLWS still possible. After 16z...a powerful cold front then moves through the TAFs with a rapid decrease in rain coverage, ceilings improving to MVFR- VFR levels and a gusty wind shift from SE to SW/WSW, gusts 35-45 kt. Lower probability for the western airports (mainly BDL-BAF) that any wet pavement could freeze and become icy as temperatures fall into the upper 20s between 21-00z Sat. Friday Night: High confidence. MVFR to VFR with gusty W to SW winds gusts up to 45 kt. Generally dry but ocean effect SHSN possible at ACK and perhaps HYA/FMH. Rapid temperature fall likely Fri night that may cause icy spots on runways. KBOS Terminal...Moderate confidence. KBDL Terminal...Moderate confidence. Outlook /Saturday through Tuesday/... Saturday: VFR. Windy with gusts up to 35 kt. Slight chance SN. Saturday Night: VFR. Windy with gusts up to 35 kt. Christmas Day: VFR. Windy with areas of gusts up to 30 kt. Sunday Night through Monday: VFR. Breezy. Monday Night through Tuesday: VFR. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Tonight through Friday night...High confidence. Increasing easterly flow this afternoon, becoming southeast and ramping up during the evening and overnight hours. Winds will reach Storm force by sunrise on Friday. Seas increase to 11-17 ft across the outer coastal waters by sunrise Friday, and continue into Friday night. Outlook /Saturday through Tuesday/... Saturday: Strong winds with gusts up to 35 kt. Rough seas up to 16 ft. Chance of snow, chance of freezing spray. Saturday Night: Strong winds with gusts up to 35 kt. Rough seas up to 13 ft. Chance of snow, chance of freezing spray. Christmas Day: Strong winds with gusts up to 30 kt. Rough seas up to 12 ft. Slight chance of snow. Sunday Night: Moderate risk for Small Craft Advisory winds with gusts up to 25 kt. Rough seas up to 9 ft. Monday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Monday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Tuesday: Winds less than 25 kt. && .TIDES/COASTAL FLOODING... 400 PM Update: Overall there were no significant changes noted regarding the concerns for coastal flooding and beach erosion. Prior forecast thinking remains valid for this update and is below: * Coastal Flood Warning for both the east and south coasts Fri morning We continue to expect widespread minor coastal flooding with pockets of moderate coastal flooding, along with beach erosion. It is rather unusual to have coastal flooding on an east to southeast wind, and for it to impact both coasts, but this is a highly anomalous system. The magnitude of coastal flooding will be determined by how quickly the winds/seas ramp up. Guidance still looking like an earlier onset is most likely. This means a greater risk of moderate flooding along the south coast for places like Narragansett Bay. The high tides occur around 7-9 AM Friday along the south coasts, and in the 10 AM to noon timeframe across the eastern MA Coast. Given an ESE wind direction and support from the various guidance, we are expecting a 1.5 to 3.5 foot storm surge. Typically vulnerable shoreline roads may become flooded and impassable within a few hours of high tide. In addition, there may be significant beach erosion on the south coast, including ocean-exposed beaches of Rhode Island and Westport. Significant beach erosion may also occur on the south side of Marthas Vineyard and Nantucket. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...Wind Advisory until 7 PM EST Friday for CTZ002>004. MA...Wind Advisory until 7 PM EST Friday for MAZ002>004-008>012-026. Winter Weather Advisory until 7 AM EST Friday for MAZ002-008- 009. High Wind Warning until 7 AM EST Saturday for MAZ005>007- 013>024. Coastal Flood Warning from 5 AM to 2 PM EST Friday for MAZ007- 015-016-019>024. RI...High Wind Warning until 7 AM EST Saturday for RIZ001>008. Coastal Flood Warning from 5 AM to 2 PM EST Friday for RIZ002- 004>008. MARINE...Storm Warning until 7 PM EST Friday for ANZ230>237-254>256. Storm Warning until 1 AM EST Saturday for ANZ250-251. && $$ SYNOPSIS...Loconto/BW NEAR TERM...Belk/Loconto/BW SHORT TERM...Loconto LONG TERM...BW AVIATION...Belk/Loconto/BW MARINE...Loconto/BW TIDES/COASTAL FLOODING...Staff
Area Forecast Discussion
National Weather Service Corpus Christi TX
610 PM CST Thu Dec 22 2022 ...New AVIATION... .SHORT TERM... (Tonight through Friday night) Issued at 158 PM CST Thu Dec 22 2022 Key Messages - Very cold temperatures and single digit wind chills tonight and tomorrow - Strong winds over the coastal region and Gulf waters The strong cold front we have been talking about over the last several days is right on our doorstep. MSAS analysis and surface observations place the front across the Hill Country. Temperatures are currently in the 30s across the Austin-San Antonio area while we are still sitting around 60 degrees across South Texas. Temperatures will fall very quickly behind the front with temps in the upper 20s to low 30s by early this evening. Overnight, lows will fall into the upper teens to mid 20s. Strong CAA will keep temperatures below freezing for much of the day tomorrow. The current forecast has temps rising in the mid to upper 30s. However, there is still a chance that some spots remain below freezing all day. Another cold night is in store Friday with lows falling back into the low to mid 20s. In addition to the brutally cold temps, winds will be packing quite the punch. Strong northerly winds will develop this evening and persist through the night before finally subsiding through the day Friday. Winds will be strongest along the coast and over the waters. Lastly, there is a low end chance for precip over the waters on Friday as an upper shortwave rotates through the region as a plume of low level moisture lifts out of Deep South Texas. Temperatures will be warmer over the waters so not expecting any wintry precip. However, if this moisture shifts a bit closer to the coast, we can`t completely rule it out. Now for the hazards: Hard Freeze Warning: The Hard Freeze Warning has been extended through noon on Saturday. Temps may briefly rise above freezing for a couple of hours Friday afternoon but will quickly fall back into the low 20s. Wind Chill Warning: The Wind Chill Warning has been extended through noon on Saturday. Similar to the Hard Freeze Warning, we will climb above criteria during the day Friday but will quickly fall back Friday night. We likely won`t see the single digit wind chills, generally in the 10-15 degree range. Wind Advisory: The Wind Advisory has been expanded to include inland Kleberg and Jim Wells counties. Recent runs of the HRRR (it`s been handling this front very well) continue to hint at frequent gusts to around 40 MPH overnight. The Advisory remains in effect through noon Friday. Fire Weather: Low RH values and strong winds across the Coastal Bend tomorrow may result in a brief period of elevated fire weather conditions. See the Marine section below for the Gale Warning. && .LONG TERM... (Saturday through next Wednesday) Issued at 158 PM CST Thu Dec 22 2022 Key Messages: - Cold freezing nights through Sunday night - No significant precipitation chances with a warm up next week A trough axis will move over the region Saturday and Sunday around the SW periphery of the broad deep trough over the NE CONUS, maintaining the surface ridge and cold temperatures over South Texas through the weekend. Will see some moderation of temperatures into the upper 30s on Saturday with abundant sunshine. Expect another hard freeze Saturday Night/Sunday morning due to the aforementioned conditions and strong radiational cooling. Highs will be a bit warmer Sunday as the surface ridge begins to erode but still only in the mid 40s (25 degrees below normal). Yet another trough swings through the area on Monday sending a weaker reinforcing surface ridge into South Texas Monday Night. However the flow becomes onshore again on Tuesday allowing for more warming into the mid 60s as the next trough enters the northern Rockies. && .AVIATION... (00Z TAFS) Issued at 602 PM CST Thu Dec 22 2022 Expect a mixture of MVFR and VFR ceilings this evening, followed by predominate VFR conditions after 06z Friday. Expect VFR to then continue for the remainder of the TAF period. Strong to very strong north surface wind expected this evening/early tonight, followed by a gradual decrease in wind speeds during the 06-12z Friday period. Afterward, generally moderate to breezy north wind during the mid/late morning hours Friday, becoming weak to moderate toward the end of the TAF period. && .MARINE... Issued at 158 PM CST Thu Dec 22 2022 A strong cold front will push offshore early this evening leading to very strong northerly winds. A Gale Warning is in effect through Friday evening as winds gust up to 45 knots at time. It`s possible we see a few gusts to storm force overnight. In addition, seas will elevated to 15-18 feet. Conditions will slowly subside Friday afternoon with a few gusts to gale possible through the evening hours. Moderate to strong offshore flow Saturday through Sunday afternoon will subside to weak to moderate on Monday as high pressure settles over the NW gulf. Small Craft Advisory conditions likely persist for the gulf waters through Sunday morning. Moderate to strong onshore flow returns by Tuesday night. A weak cold front is forecast to move off the coast Monday Night resulting in moderate offshore winds. Onshore winds return Tuesday becoming moderate to strong by Wednesday and will likely result in Small Craft Advisory Conditions. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 22 36 25 38 / 0 0 0 10 Victoria 19 34 23 39 / 0 0 0 0 Laredo 26 38 25 40 / 0 0 0 0 Alice 21 36 23 38 / 0 0 0 0 Rockport 22 37 25 37 / 0 0 10 10 Cotulla 23 38 22 41 / 0 0 0 0 Kingsville 23 36 24 37 / 0 0 0 10 Navy Corpus 26 37 30 38 / 0 0 10 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...Hard Freeze Warning until noon CST Saturday for TXZ229>234- 239>247-342>347-442-443-447. Wind Chill Warning until noon CST Saturday for TXZ229>234- 239>247-342>347-442-443-447. Wind Advisory until noon CST Friday for TXZ231>234-241>247- 342>347-442-443-447. GM...Gale Warning until 6 PM CST Friday for GMZ231-232-236-237-250- 255-270-275. && $$ SHORT TERM...TC LONG TERM....JM AVIATION...WC/87
Area Forecast Discussion
National Weather Service Dodge City KS
441 PM CST Thu Dec 22 2022 ...Updated Aviation Discussion... .SHORT TERM...(This evening through Friday night) Issued at 141 PM CST Thu Dec 22 2022 A little warming this afternoon on the HRRR shows temps increasing to the mid single digits above zero along the southern tier of counties, to around 0 degrees along the Interstate 70 corridor. The momentum transfer weakens through late afternoon, and a marginal decrease in wind speed should be realized, noted in the HRRR 2m wind fields as well as the LAV guidance which ramps sustained wind speeds down to around 20kts by this evening. The bulk of the cold air advection has already occurred, so temperatures are not anticipated to fall that much more overnight. That said, the ark valley west across GCK into eastern Colorado is favored by the models for the coldest air which NAM takes temperatures into the -10 to -15 deg F range, while the rest of the forecast area falls into the the 0 to 10 below range, with sustained 20 mph winds gusting to 30. The Wind Chill Warning remains in effect through noon Friday. Model consensus warms temp in to the teens over the bulk of the area Friday afternoon, as winds significantly weaken to around 10 to 15 knots. Wind chills will still be dangerous Friday morning, although not quite as extreme, probably struggling to reach warning criteria along the Oklahoma state line. Look for wind chills Friday morning approaching 30 below zero north of highway 400. .LONG TERM...(Saturday through Thursday) Issued at 141 PM CST Thu Dec 22 2022 Significant airmass modification is seen going into the weekend. Light westerly winds return with weak downslope warming as the main arctic airmass continues to retreat into the Midwest. While still a cold and dry airmass, the NBM forecast warms overnight lows into the single digits above zero by Sunday morning while highs in the 20s on the lower Plains and the 30s on the High Plains modify to the 30s to low 50s west by Sunday afternoon. This overall trend looks to carry into the workweek as an amplified upper ridge develops into the Rockies region with potential for better downslope trajectories in the boundary layer. The ECMWF ensemble mean at Liberal on Wednesday is 63 degrees. The next major synoptic scale trough appears to develop around Day 7 late Thursday into Friday. Canadian/GFS and ECMWF all show a sharp synoptic scale trough moving into the Plains, as pressure falls develop a typical Elkhart low that ejects eastward ahead of what appears to be a rather insignificant cold front. ECMWF ensemble members produce anywhere from nothing - to a range of 0.01 to 0.06 inches of precipitation on a 6 hour basis, and a trace to just under an inch of snow. In those same timescales. The NBM is accounting for a lot of this already with about a 20 percent chance of snow or fzra/mixed phase on Thursday. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 435 PM CST Thu Dec 22 2022 VFR conditions for the entirety of the period for all TAF sites. Gusty north to northwest winds up to 30kts to start diminishing after sunset around 02Z to around 15kts due to clearing skies and weakening gradient. A few lingering lower level clouds present will clear after this point as well remaining mainly clear through the end of the period. Northwest winds will continue to diminish to less than 10kts as high pressure builds in towards sunset near the end of the period with no other weather elements expected at this time. && .PRELIMINARY POINT TEMPS/POPS... DDC -14 18 0 30 / 0 0 0 0 GCK -15 16 -1 30 / 0 0 0 0 EHA -11 20 4 35 / 0 0 0 0 LBL -11 18 0 33 / 0 0 0 0 HYS -12 14 -4 23 / 0 0 0 0 P28 -7 18 3 26 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... Wind Chill Warning until noon CST /11 AM MST/ Friday for KSZ030- 031-043>046-061>066-074>081-084>090. && $$ SHORT TERM...Russell LONG TERM...Russell AVIATION...Lowe
Area Forecast Discussion
National Weather Service Des Moines IA
551 PM CST Thu Dec 22 2022 ...Updated for the 00z Aviation Discussion... .DISCUSSION.../Tonight through Thursday/ Issued at 305 PM CST Thu Dec 22 2022 Key Messages: - Blizzard conditions combined with dangerous wind chills will create life threatening conditions for anyone that ventures out tonight through Friday, particularly over northern/central Iowa - Bitter cold through Saturday morning, then gradual upward temperature trend - Light snow chances parts of Iowa Christmas Day Details: The snow has pushed into eastern Iowa as of early this afternoon with COOP and spotter reports showing snowfall was between 2 to 4 inches in most places. Several reports between 4 and 5 inches came were received from around the Webster, Hamilton, and Boone county area. The arctic front that brought this snowfall is over eastern Lake Michigan and stretches to near Little Rock to near San Antonio. The parent trough of this front is digging southeastward toward the western Great Lakes while surface low pressure develops over the Ohio Valley. As this surface front pulls away, the clouds are also departing to the east leaving behind a clear sky over western into central Iowa. Winds in the wake of the front have been increasing with gusts between 25 and 35 mph this morning and that has increased into the 30 to 40 mph range now. Temperatures continue to fall and with the increasing winds, the entire area is solidly in Wind Chill Warning criteria with most places at or below -35F. With the fresh snow and these winds, GOES-East day snow fog RGB show a widespread field of blowing snow, which has a bit of milky appearance to it over western/central Iowa, eastern/central South Dakota, eastern/central Nebraska, and Minnesota. Frankly, it is amazing to see such a large area of blowing snow. Visibilities thus far this afternoon in Iowa have generally bottomed out around a half a mile with KEST (ASOS), KEBS (AWOS), and KCIN (AWOS) reporting such. Recently, KCAV (AWOS) reached a quarter of a mile. We`ve also seen social media reports around Pocahontas of quarter mile visibility, drifting snow, and county plows being pulled off the roadways. As the surface low moves into the eastern Great Lakes, explosive deepening of this low will occur, which will increase the pressure field between the eastern Great Lakes and a ~1050mb high moving down the eastern spine of the northern Rockies. For Iowa, this means winds will be stronger tonight and Friday then they have been so far. Current forecast for wind gusts is toward the BUFKIT mean mixed layer wind versus the top of the mixed layer, which are impressive around 50 knots over northern Iowa and also shown in HRRR runs. For now, peak gusts were kept between 40 and 50 mph after midnight tonight into Friday evening, but will monitor trends in case we need to trend towards the top of the mixed layer. With these stronger winds continuing to loft snow, we continue to forecast blizzard conditions tonight into Friday and the headlines are in good shape. Those blizzard conditions will be most likely in rural, open areas so if you are in a sheltered, city/urban location and it doesn`t look bad, do not be deceived. While the blizzard conditions alone are a concern for personal safety, the bitterly cold air with these winds will create wind chills of -35F or lower across all of Iowa. Stealing from the midshift`s discussion, wind chills this low are uncommon and happen on average maybe a few hours per year (10hr/yr at Estherville to 2hr/yr at Des Moines), so this is a somewhat rare, prolonged cold scenario for Iowa. If you were to venture out tonight or Friday and become stranded due to a vehicle break down, stopped in traffic due to an accident, or go off the roadway due to poor visibility, these wind chills would be dangerous and life threatening if exposed for a short period. We don`t use those words lightly or often, but that is the current scenario that we see unfolding, particularly over northern and central Iowa. Wind chills will generally be below -25 if not -30F or lower across the state through Saturday morning. While the Wind Chill Warning conditions are currently included in the Blizzard Warning and Winter Storm Warning, will need to issue a separate wind chill headline once the other warnings end. While the forecast is dry through Friday and Friday night, the RAP shows a thin layer of saturation dropping into northern Iowa in the afternoon and evening with little lift noted in cross sections. The RAP and HRRR BUFKIT soundings show that the not fully saturated profile warms (yes, warms) to near the lower end of the -18 to -12F dendritic growth zone while at the same time further drying. There is no ice introduction so we could see freezing drizzle or perhaps flurries briefly over northern Iowa, but confidence was too low to include it at this time. It will remain blustery through Saturday as the trough and surface low wrap up and move northeast into the Quebec province. With around 36 hours of blowing snow, crystals will have been fragmented down and the relatively lighter winds should result in blowing snow being not be as prevalent. There could still be streamers across roadways, which could pose a travel risk. After Saturday morning, the coldest period will be in the past with temperatures forecast to rise gradually into next week. The next chance for light snow will come from a clipper system that looks to track through the region later this weekend. Moisture will be limited and it will take top down saturation to overcome the dry low levels. Cross sections do not show robust lift, but sufficient for light snow. Compared to yesterday, the 100 member grand ensemble is slower with the arrival of snow holding off until later in the afternoon with it more tracking through southern Minnesota, northeast half of Iowa, and southwest half of Wisconsin. So, a bit of light snow with amounts around an inch possible in parts of the state are possible Christmas Day. && .AVIATION.../For the 00Z TAFS through 00Z Friday evening/ Issued at 543 PM CST Thu Dec 22 2022 Main concern for terminals remains visby reductions from blowing snow which will last for the TAF period and beyond. Visby will be largely IFR and LIFR. Winds will increase around 06z tonight and may exceed 45kts at times, especially for eastern terminals. MVFR and IFR cigs will prevail through the period. && .DMX WATCHES/WARNINGS/ADVISORIES... Blizzard Warning until 6 AM CST Saturday for IAZ004>007-015>017- 023>028-033>039-044>050-057>062. Winter Storm Warning until 6 AM CST Saturday for IAZ070>075- 081>086-092>097. && $$ DISCUSSION...Ansorge AVIATION...Jimenez/Fowle
Area Forecast Discussion
National Weather Service Grand Rapids MI
1107 PM EST Thu Dec 22 2022 LATEST UPDATE... Update .UPDATE... Issued at 1107 PM EST Thu Dec 22 2022 Synoptic portion of the event is still ongoing in eastern sections of the forecast area towards U.S. Highway 127 from Mt. Pleasant to Jackson. Snowfall from this portion of the event has been on the order of 2 to 4 inches for the most part. We are currently shifting into the lake effect portion of the event. The surface low is located near Oscoda with a trailing Arctic front stretching south into Southeast Lower Michigan just west of Ann Arbor. The front has now cleared the entire forecast area with much colder air flowing in on westerly winds. Temperatures have already plunged to 14 at Fremont and Ludington. To the west across the lake, it is in the teens below zero already west of Madison WI. Lake effect has begun with 25+ dbz echoes already occurring in a sheared environment (which is not good for lake snow). Once wind direction consolidates a bit more in the vertical which happens towards daybreak, the lake effect should really increase in coverage and intensity. The wind in the vertical is completely linked up or more uniform in direction by midday tomorrow. We expect the worst of the conditions to occur Friday and Friday night. Forecast winds in the mixed layer remain above 40 knots. Conditions that are already not great with 2-4 inches of new snow and winds gusting to 30 knots should become much worse as snow becomes heavier, more powdery with time and wind gusts that may exceed 40 knots. Obviously, the Blizzard Warning and Winter Storm Warnings remain in place and unchanged. The areas that will see the least snow from this entire event will be interior portions of the state from Mt Pleasant south to St. Johns and in far southeast Jackson County towards Brooklyn. Otherwise, major impacts are expected along the spine of Highway 131 and points to the west. 850-925mb layer omega really tells the story of the next 24-36 hours. We will see a major convergence zone near/in between I-96 and I-94 over Southwest Lower Michigan. This converence zone is driven by the cold air wrapping around the bottom of the lake. The thermal gradient that will be in place between air flowing off a lake surface that is 42 degrees and air flowing into far Southern Lower Michigan that will be in the single digits will create a frontal zone essentially that will drive a dominant lake band. Snowfall rates in this zone (Muskegon to Grand Rapids to Eaton Rapids to Battle Creek to South Haven) will approach and exceed an inch an hour at times. Suffice it to say given the snow, wind and powdery nature of the snow travel will be life threatening much of the time. Keep in mind salt loses much of its effectiveness as temperatures fall towards 10 degrees. && .DISCUSSION...(This evening through next Thursday) Issued at 346 PM EST Thu Dec 22 2022 -- Blizzard Conditions Friday / Snow showers into Sunday - 4 pm Thursday till 1 am Friday We have been writing about this event for over a week now. The bottom line is nothing much has changed in terms of the actual forecast through the weekend. We have the snow from the warm advection part of the system moving through the area from now until late this evening. Since the 1000/850 moisture transport vectors are aimed at eastern part of lower Michigan with this event (late afternoon into early evening), it is that part of the state that will likely have the greatest snowfall from this part of the event. Based on HREF, NAMNEST, HRRR, RAP and just simple I have been forecasting for 46 years, I am thinking 3 to 6 inches from this part of the storm. This part of the system should largely be done by early Friday morning. - 1 am till 7 am Friday The second part of the system will be the dangerous part of the system for us. This is when the arctic air surges in we are expecting an 5 to 10 degree temperature drop in one hour. This has happened upstream, MKE fell from 28F to 19F in one hour (for example). This is when the lake effect snow kicks in. So, there may be a break in the snow near and east of US-131 after midnight as a result of that. However for areas west of US-131 the snow showers should follow the front quickly. In fact the area between Holland and South Haven get into a strong convergence band after 1 am. This band will be aimed toward Kalamazoo. So in the period between 1 am and 7 am, there could be another 2 to 4 inches in that area. Here is the glitch through, this is behind the arctic front, so winds will be kicking up with this part of the event. So south of a line from Muskegon to Grand Rapids to Battle Creek between 1 am an 7 am, there may already be near blizzard to blizzard conditions in that area. Outside of that I would expect mostly and inch of less after midnight. - 7 am Friday through 7 pm Saturday The boundary layer wind turns more westerly by mid morning Friday. Inversion heights rise from around 5000 ft at sunrise to near 7000 by midday. The DGZ is nearly on the ground and there is strong lift in the cloud bearing layer. There is also the I-94 and I-96 convergence bands wiggling around some but not much through this time period. Winds in between 1000 ft and 5000 ft will be in the 40 to 50 knot range from the west. Air temperatures will be near 10F. All of this leads to mostly small be densely falling snowflakes on very strong winds. Hence a blizzard (3 hours or more with visibilities near or under 1/4 mile and frequent wind gusts to 35 mph our more). This will lead to two bands of heaver snow accumulations, one near I-94 and one near I-96. As for where the heaviest snowfall will be remember we have 40 to 50 knot winds in the cloud bearing layer. During the event in mid November we had 20 to 30 knot winds in the cloud bearing layer, that resulted in the heaviest snowfall near US-131. With winds 10 to 20 knots stronger, I would have to believe the heaviest snow will be EAST of US-131. Seems a good 6 to 12 inches could fall during this time in the heaver snow bands. Outside this area we will have snow showers but not all that heavy. There will still be winds gusting to 40 to 50 mph and temperatures near 10F. So wind chill values will be near -10F most of the time from mid morning Friday into the day on Saturday. So I do not believe that area will have real blizzard conditions but being outside for any lenght of time will still be dangerous. That is why to keep the Winter Storm Warning. One large scale through on all of this, we have a 170 knot polar jet core crossing a baroclinic zone with a strong shortwave today. That happens well south of us. This does lead to a surface wave on the cold front that runs into very difluent winds aloft over southeastern Canada (Ontario and Quebec) tonight into Friday. This causes rapid deepening of the surface low. It is that deepening of the surface low with an upstream 1050+ mb high that leads to the strong winds Friday into Saturday. - Warm up and melting snow follow for mid to late next week While all this is happening we have one of those 170 to 180 knot east Asia jet features crossing the mid Pacific by early next week. That will do what it always does, create a deep trough over the western CONUS and large upstream ridge over the eastern CONUS. That means by mid week we get booted out of the cold air and go back into warm air. This is one more system that takes southeast from MN to KT early next week. Currently we expect that to miss us to the south Mon/Tue but if it shifts a touch north we could see a little light snow from that Mon/Tue. The ridge building gives milder by dry weather mid week, but toward the weekend (New Years) we get that western trough to move east into the central CONUS. That will kick out a series of southern stream system so we likely will see rain from that or rain to snow if one of those systems can pull down Just enough cold air as it scoots by us. We will have to watch how this plays out for possible ice jams etc.. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 739 PM EST Thu Dec 22 2022 The synoptic (system) snow is moving through Southwest Lower Michigan at this time (00z). The arctic front that is driving much of this snow is situated just east of GRR (frontal passage occurred right at 00z) and just to the west of AZO at this time. The system related snow will continue off to the east with the front so a tapering of the snow as was expected this evening is on schedule. Flake size will get smaller tonight as the Arctic air pours in and winds increase out of the west and northwest. Lake effect snow will begin this evening and become more steady state towards and especially after midnight. Non stop lake effect snow is then expected through Saturday night. Bottom line...system snow is shifting east...slight lull in the snow in the late evening hours...then lake effect snow ramps up after midnight. What this means for aviation is a continuation of very poor conditions for the next 24 hours. Widespread IFR and LIFR are in place at 00z and this will not change much as the system snow is replaced by lake effect snow and blowing snow (as the wind increases). Visibilities as we head into the day on Friday will frequently be at or below one mile. KMKG, KGRR and KAZO will see the worst of the conditions with visibilities at 1/4 and 1/2 a mile. Winds from the west and northwest tonight and Friday will be increasing into the 20-30 knot range with gusts towards and above 40 knots. Whiteout conditions are expected at times at all of our TAF sites late tonight and especially in the daylight hours of Friday. Given the magnitude of the winds from a westerly direction, north/south runways will likely drift shut Friday. && .MARINE... Issued at 346 PM EST Thu Dec 22 2022 Given the rapidly deepening storm that heads into central Ontario and becomes a 970 mb low while we have a 1055 mb high to our west, it surly makes sense to have STORM WARNING in our Near Shore. We have a gale warning in front of it to allow a time for winds to ramp up. Also we have a freezing spray warning since winds of 40 knots and temperatures in the teens will lead to rapid ice buildup on any ships on Lake Michigan. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Blizzard Warning until 7 PM EST Saturday for MIZ037-038-043-044- 050-056-057-064-065-071-072. Winter Storm Warning until 1 AM EST Saturday for MIZ039-040-045- 046-051-052-058-059-066-067-073-074. LM...Heavy Freezing Spray Warning until 7 PM EST Saturday for LMZ844>849. Storm Warning until 1 PM EST Saturday for LMZ844>849. && $$ UPDATE...Duke DISCUSSION...WDM AVIATION...Duke MARINE...WDM
Area Forecast Discussion
National Weather Service Gray ME
1035 PM EST Thu Dec 22 2022 .SYNOPSIS... A large low pressure system impacts New England tonight through Friday night. This system will bring wintry precipitation at first, and then heavy rain, possible flooding, strong winds, and significant coastal impacts as we enter a period of high astronomical tides. Drier and breezy conditions are expected over the holiday weekend as high pressure builds towards the region. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... 725 PM Update... Little change to the forecast right now, except to load in latest temperatures which are a couple degrees cooler than previously advertised. This has little bearing on the going forecast logic. Previously... Peaceful evening in store with high impact storm on the doorstep. Make final preparations this evening! Cirrus continues to flood into northern New England this afternoon as this system comes together across the Ohio Valley. Low level stratus has become thicker across much of the interior over the past few hours. Expect this trend to continue, particularly across southern NH as precip is quickly filling in through eastern NY state. Precip overspreads mainly approaching midnight. This will likely be in the form of snow or some patchy freezing drizzle. Low levels have visibility been saturating (clouds mentioned above) and now to start precip off, just need that deeper moisture. Winds remain light and variable through midnight, but will trend SE afterwards. && .SHORT TERM /MIDNIGHT TONIGHT THROUGH FRIDAY NIGHT/... 1035 PM Update... Refreshed temperature trends through the overnight and morning hours with latest hires guidance, namely the HRRR which seems to be handling current observed trends well with wet-bulb processes cooling surface temperatures through the southern half of the area. Which this in mind, re-ran the weather/accumulation forecast with a wet-bulb adjustment for snowfall which resulted in higher totals by a couple inches through the mountains. It also resulted in light accumulations through the foothills and toward the coastal plain; but these shouldn`t be of much consequence. Another adjustment made was to the wind gust forecast Friday evening with steep lapse rates through the mid-levels tapping into a strong southwesterly jet. This prolongs damaging wind threat, but fits well within the existing High Wind Warning. Previously... A high impact storm blasts through northern New England Friday. Primary change was accentuating a period of strong, damaging winds NW of the Whites and western ME mountains. Some temp trends also brought in the chance of more wet snow accumulation to the north where a Winter Weather Advisory has been issued. - Winds: Increasing pres gradient along a lifting jet will arrive late tonight. This will stream over the Whites and be swept to lower elevations NW of the mountains. Have pushed some gusts to 70 mph here, as well as increased winds/gusts at the higher summits of the White mountains where upwards of 150 mph will be possible through at least the early morning hours. The other wind max will fall along the ME coast. This is where onshore flow will slowly track north through the day. GEFS wind probs of > 50 kt gusts do increase as the jet lifts north, and there is a possibility stronger winds do penetrate further inland across the ME capitol region into some of the central foothills. Still, think the chance of 70 kt gusts here is maximized at some of the elevated ocean platforms or along the Midcoast. Local guidance also has a wide spread of peak wind gusts for Rockland. - Coastal Flooding: See Tides/Coastal Flooding section. Of discussion today was the freshwater runoff factor for locations that will be susceptible to moderate/major coastal flooding. Once site in particular is Portland where heavy rain will have been underway prior to the rising high tide Fri AM. Additional runoff from some of the hilly urban environment will be slow to drain due to elevated tides/surge. Thus, some calculated surge impacts may be enhanced due to heavy runoff. - Winter Weather: A chilly day today, and increasing clouds through the day will help lock in some cold air tonight. This should set the stage for a bulk of the area to begin as snow late tonight. The exception may be the southern ME coast and southern NH. Snowfall rates increase into the foothills and mountains through Fri morning, with a transition to rain expected towards noontime through Jackman. Snow ratios will again be low with warm temps and obliterating dendrites amid the high winds incoming. So, wet snow accumulation will again be possible for the Winter Weather Advisory area. In addition, a brief period of freezing drizzle will be possible through the early morning hours in the foothills and parts of the interior, but should transition to rain quickly. - Heavy Rainfall: Not much change in QPF forecast at this time. Although some high res guidance and HREF forecasts are indicative of some enhanced rainfall rates Friday morning. Would expect some flash flooding concerns, especially where previous hard snowpack has covered drains or created channels where rain can initially pool. Rain tapers quickly late in the afternoon, with a change back to snow showers...but accumulations here are not expected. - Flash Freeze: Still on the table for Friday night. With such a short period of warm temps...this should be enough to soften top of snowpack, add more snow/rain content, and then quickly refreeze overnight. This will create the potential for some loading issues as well as freezing areas of standing water. Any damp surfaces that are not dried out by brisk SW winds will be slick come Saturday morning. - River Flooding: See Hydrology section. Breezy conditions continue Friday night, but the highest should be behind us. Will continue to watch some hires solutions depict showers/squalls Fri evening before winds start a very slow decrease through the weekend. It will be quite different to have cooler temps arriving from the SW. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Overview: Deep trof and below normal temps will be the rule for much of the week before the pattern flips back to warmer than normal very late in the period. Below normal precip expected as well. Impacts: Besides the colder weather there are no significant weather impacts anticipated in the extended. Forecast Details: With very active weather in the short term the extended is primarily using the NBM. Trof will dominate the pattern with cold and dry offshore flow prevailing for much of the period. Some mtn snow showers are likely...but widespread precip threat looks low. By the middle of next week a strong Pacific jet stream will flood much of the CONUS with warmer than normal temps and that will eventually work its way into the local area beyond the forecast range. The next coherent signal for widespread precip will be early in the new year. && .AVIATION /04Z FRIDAY THROUGH TUESDAY/... Short Term...Trending MVFR this evening, becoming IFR tonight through Friday. LIFR will be possible in BR/+RA/SHSN. Very gusty winds, up to around 50 kts, will be possible at coastal TAF sites and towards KHIE where locally strong downslope winds will impact. Expect LLWS through Friday morning and afternoon for all sites. Winds shift SW overnight Friday, slowly decreasing. Long Term...Widespread VFR conditions expected. Surface wind gusts near 25 kt for all terminals both Sat and Sun afternoons. && .MARINE... Short Term...SE winds build towards Storm force tonight as a large storm arrives from the south. Winds shift S Friday evening, and then SW overnight...slowly slackening to Gale force. Seas will also quickly increase towards 20 ft tonight through Friday, remaining around 15 ft through Fri night. Long Term...Strong SCA conditions expected to be ongoing with potentially gale force gusts near 25 nm from shore. Those winds will linger into Sun night before gradually diminishing. An end to the SCA conditions looks likely by Mon night. && .HYDROLOGY... Confidence continues to grow for widespread flooding Friday into early Saturday with significant impacts to travel. Moderate to heavy rainfall (1 - 3") along with snowmelt will lead to the potential for flash, urban, and small stream flooding impacts, as well as scattered minor and isolated moderate river flooding. There are a few adjustments to the latest forecast that could help limit the runoff and subsequent magnitude of flood impacts. First is the faster storm movement which reduces the melting window from 12 hrs to 6-9hrs, and secondly is the amount of snow at the onset of the event. Despite these favorable trends, the region will still experience widespread flooding from the moderate to heavy rainfall over frozen ground. The area snowpack will work to both dampen and exasperate the area flooding in the course of this event. South of the foothills to the coast the SWE is 0.5-1.5”. Here the snowpack is likely to ripen, and for the immediate coast we can expect a nearly complete melt out. At the coast runoff will be slowed by rising tides with peak rainfall rates forecast to simultaneously occur with high tide. Poor drainage flooding is expected at the usual coastal hot spots. From the foothills northward the SWE is 2-4”. This deeper and colder snowpack has a lower density and is not expected to ripen and melt out in this event. On the contrary, much of the rainfall will be held in the snowpack where it will be slowly released into the waterways. There will still be sufficient runoff for flooding in the mountain areas due to the rapid runoff in the hills and the small storage capacity of the streams and creeks. && .TIDES/COASTAL FLOODING... Storm surge guidance continues its trend with the rapid onset of storm force winds late tonight and Friday morning. ESTOFS continues to be the most conservative storm surge guidance available however even this model brings Portland to 13.8 feet at high tide Friday morning. Other guidance is even higher such as the Snap-X and ETSS solutions topping at around 14.1 feet in Portland which would be one of the highest tides of all time. There is some uncertainty with this forecast as there has been large changes with guidance in a short period of time as the core of the strongest winds appears to be advancing slightly faster than progged a couple days ago. In any case, moderate coastal flooding can be expected with pockets of major flooding possible. Have continued a Coastal Flood Warning for the entire coastline of western Maine and the Seacoast of New Hampshire. Ran this product through the early afternoon hours as the storm force southeasterly winds will be slow to allow the tide out during the midday hours Friday. Communities that have a southeast exposure such as Hampton, New Hampshire may be particularly hard hit with the potential for up the three feet of water in some locations. Large, battering waves will continue to impact the region through Friday night and potentially into Saturday. All-time storm tide records for Portland, Maine all in MLLW (1912-Present). #1. 14.17` set on 2/7/1978 (Blizzard of `78) #2. 13.98` set on 1/9/1978 #3. 13.79` set on 1/4/2018 #4. 13.40` set on 1/4/1990 #5. 13.31` set on 3/16/1976 && .GYX WATCHES/WARNINGS/ADVISORIES... ME...Winter Weather Advisory until noon EST Friday for MEZ007>009. High Wind Warning until 2 AM EST Saturday for MEZ007>009-014- 018>028. Flood Watch from 7 AM EST Friday through Saturday morning for MEZ007>009-012>014-018>028-033. Wind Advisory until 2 AM EST Saturday for MEZ012-013-033. Coastal Flood Warning from 7 AM to 2 PM EST Friday for MEZ023>028. NH...Winter Weather Advisory until noon EST Friday for NHZ001>003. High Wind Warning until 2 AM EST Saturday for NHZ001>003-010- 013-014. Flood Watch from 7 AM EST Friday through Saturday morning for NHZ002>015. Wind Advisory until 2 AM EST Saturday for NHZ004>009-011-012- 015. Coastal Flood Warning from 7 AM to 2 PM EST Friday for NHZ014. MARINE...Storm Warning from 4 AM Friday to 3 AM EST Saturday for ANZ150>154. && $$ UPDATE...Casey NEAR/SHORT TERM...Cornwell LONG TERM...Legro HYDROLOGY...Jamison TIDES/COASTAL FLOODING...Cannon
Area Forecast Discussion
National Weather Service Houston/Galveston TX
537 PM CST Thu Dec 22 2022 ...New AVIATION... .SHORT TERM... (This evening through Friday Night) Issued at 308 PM CST Thu Dec 22 2022 The Arctic cold front has just passed Houston metro area this afternoon. Temperatures have already fall below freezing across our northernmost counties with strong winds of around 20-25 mph and gusts upwards of 30-40 mph, warranting a wind advisory across our area. Strong CAA and clear skies should bring lows in the teens for all of SE Texas and lower 20s along the immediate coast. Frigid temperatures and strong winds should put minimum wind chill indicies near or below zero overnight/early Friday morning. Therefore, all of SE Texas will be under Wind Chill Warning from 6 PM today until noon Friday. HRRR continues to out perform other guidance, such as the NBM, when it comes to handling the FROPA. Therefore, I have opted to lean closer towards that solution and other high resolution guidance heading into Friday. With that being said, much of SE Texas, outside of the immediate coastline, will likely stay below freezing all day tomorrow. HREF probabilities further confirm this suspicion, depicting a firm 80% probability of sub freezing conditions for areas along and north of I-10 during peak solar heating. This means that many locations across the region may remain below freezing for 36 hours or more. Therefore, a Hard Freeze warning will be in effect from 6 PM today through noon on Saturday. These frigid conditions may result in hypothermia or frostbite if precautions are not taken. Avoid outdoor activities and dress appropriately for the weather. Frost and freeze conditions will kill sensitive plant life, so take steps now to protect them while you still can. Water pipes should be wrapped, drained, or allowed to drop slowly to prevent freezing and possible bursting. 03 && .LONG TERM... (Saturday through next Wednesday) Issued at 308 PM CST Thu Dec 22 2022 Did not make a lot of changes from the previous package with the cold arctic air mass in place across SE TX on Sat. Despite weak- ening CAA (as the surface high slowly drifts east), highs on Sat will be in the mid and upper 30s for most of the CWA...around 40 closer to the coast. The light to moderate north winds will keep wind chills in the teens in the morning and in the 30s to 40s in the afternoon. With mostly clear skies (and light north winds) a return of sub-freezing temperatures is expected the night of the 25th (Christmas night). Overnight lows will dip into the low/mid 20s. Hard Freeze Warnings will likely be issued during this time- frame. Highs for Christmas day could climb into the mid to upper 40s with wind chills in the upper 30s (so, progress!). A weak cold front late Mon will just help to reinforce this cold dry air mass for Mon night with lows back to freezing and/or sub- freezing for northern parts of the FA. But, with the upper ridge building over the region and onshore winds returning by Tues, we should see warmer temperatures through mid week. 41 && .AVIATION... (00Z TAF Issuance) Issued at 537 PM CST Thu Dec 22 2022 With the strong cold front now off the coast, the area will be seeing decreasing clouds this evening while N to NW winds remain strong and gusty on through the overnight hours. TAF sites have possible MVFR ceilings for a couple more hours (maybe until around 03Z) followed by SCT250 or SKC for the remainder of the 23/00Z TAFs. Gusty N to NW winds (around 22ish with gusts to around 30 inland and around 30ish with gusts around 40 or higher at the coast) can be expected with a gradual decrease as the day progresses tomorrow. 42 && .MARINE... Issued at 308 PM CST Thu Dec 22 2022 With the cold front finally off the coast, strong north to north- west winds will be strengthening this evening and tonight. A Gale Warning remains in place for our bays and Gulf waters through 3PM tomorrow afternoon. (The expiration time was extended earlier to- day to match neighboring offices.) Gusts up to 50kt are expected. Elevated seas with wave heights from 7-14ft, occasional seas near 17ft will be possible over the offshore waters late tonight. This period of strong offshore winds overnight could also produce some extreme low water levels across the bays by tomorrow(Fri) morning. A Low Water Advisory remains possible. These gale-force winds are forecast to gradually weaken by tomorrow afternoon; but, Advisory conditions could remain in place (mainly over the coastal waters) through late Sat. Light to moderate onshore winds could return by next Tues. 41 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 13 27 18 37 / 0 0 0 0 Houston (IAH) 15 29 20 39 / 0 0 0 0 Galveston (GLS) 23 34 26 41 / 0 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Wind Advisory until midnight CST tonight for TXZ163-164-176>179- 195>200-210>214-226-227-235>238-300-313. Hard Freeze Warning until noon CST Saturday for TXZ163-164- 176>179-195>200-210>214-226-227-235>238-300-313-335>338- 436>439. Wind Chill Warning until noon CST Friday for TXZ163-164-176>179- 195>200-210>214-226-227-235>238-300-313-335>338-436-438-439. Wind Advisory until noon CST Friday for TXZ335>338-436>439. GM...Gale Warning until 3 PM CST Friday for GMZ330-335-350-355-370- 375. && $$ SHORT TERM...03 LONG TERM....41 MARINE...41
Area Forecast Discussion
National Weather Service Lincoln IL
819 PM CST Thu Dec 22 2022 .SYNOPSIS... Issued at 819 PM CST Thu Dec 22 2022 Dangerously cold weather will prevail across central Illinois tonight into Friday...with wind-chill values hovering in the twenty five to thirty five below zero range. In addition, the strong northwesterly winds will create considerable drifting snow...especially across rural roadways. && .UPDATE... Issued at 819 PM CST Thu Dec 22 2022 Snow has ended across the western KILX CWA this evening...with 02z/8pm radar imagery showing the back edge of the steady light snow along a Pontiac to Taylorville line. Based on radar trends as well as the latest HRRR guidance, it appears light snow will end across east-central Illinois around midnight. Total snow accumulations will be 1-3 inches across the area. Even though the accumulating snowfall is about over, will be maintaining the current Winter Storm Warning through the night due to drifting snow and bitterly cold wind chills of 25 to 35 below zero. The warning will likely be transitioned to a Wind Chill Warning extending through Saturday morning with the next forecast package in the morning. && .SHORT TERM...(This evening through Friday) ISSUED AT 315 PM CST Thu Dec 22 2022 A powerful cold front has swept across central Illinois with light to at times moderate snow continuing across central Illinois. Despite relatively light snow amounts, strong winds will result in blowing and drifting, particularly in open/rural locations. Expect widespread visibilities reduced to half to three quarters of a mile and isolated whiteout condition. Expect whiteout conditions to increase in coverage across the region this evening and tonight as winds continue to pick up. Gusts will increase into the 40 to 45 mph range this evening and overnight. As winds increase and temps fall to between 5 and 10 below zero overnight, wind chill values will dip to between 30 and 40 below. Meanwhile, snowfall has likely peaked across the area within a band of strong 850mb fgen. Latest RAP indicates this fgen band will continue to shift east through the rest of the afternoon entering Indiana early this evening, but weakening with eastward extent. A second band of frontogenetical forcing currently over Missouri will spread east this evening clipping our southern forecast area south of I-70. Widespread accumulating snow should end altogether across central Illinois by around midnight tonight. By this time, expect most of central Illinois will have seen 2 to 3 inches of snow, though this may be hard to measure due to the blowing. Some flurries will remain possible overnight as low level cyclonic flow lingers over the region. Any falling snow, even if just light flurries, could compound visibility issues from blowing snow. Friday will continue to experience very strong wind gusts peaking between 40 and 50 mph much of the day. Blowing and drifting will likely continue and remains the basis for the continued Winter Storm Warning (in addition to the dangerously cold temps). It`s important to note that conditions in town will likely be much improved compared to open/rural areas including major instates such as I-55 and I-57 which are perpendicular to the wind direction. Flurries will also be possible through the day, especially late afternoon into the evening. Accumulations will be unlikely but any falling snow will compound visibility issues. Friday night will remain gusty but should see a gradual diminishing trend. Wind chill values are expected to bottom out 20 to 30 below. .LONG TERM...(Friday night through Thursday) ISSUED AT 315 PM CST Thu Dec 22 2022 This weekend, a strong and expansive high will be in place across the Great Plains while low pressure lifts north across Quebec. Low level cyclonic flow will linger over portions of the Midwest Saturday behind the departing low and a few additional flurries will be possible as a result. Forecast soundings continue to show strong winds within the well mixed boundary layer and gusts into the 20 to 30 mph range remain possible through the afternoon. Any flurries that do fall may contribute to lower visibility due to blowing snow. Through the day Sunday, the ridge axis will spread across the lower and mid Mississippi River Valley and then along the Ohio River Valley. Winds will finally drop off as the ridge axis moves across central Illinois and some breaks in the cloud cover are possible. Temps will continue to run well below normal through the weekend with highs in the single digits and teens each day, Sunday being the warmer day by 2-4 degrees. Guidance is starting to come into better agreement with a clipper system impacting portions of the region late Sunday night through Monday. QPF amounts look fairly light with this quick moving system and there remains enough model spread that ensemble guidance is a bit broad brushed. Still, NBM 90th percentile shows potential for a couple inches of snow and expect the signal for accumulations to increase as guidance locks onto a solution over the next few days. Another high will move across the region Tuesday with southwest flow setting up as the high moves to the Atlantic Coast midweek. Temperatures will turn warmer in response with widespread 40s back in the forecast Wednesday and Thursday and a few sites may tag 50s Thursday. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 542 PM CST Thu Dec 22 2022 Back edge of the steady light snow has reached I-55 as of 2330z/530pm...with radar timing tools indicating an end to the falling snow as far east as KCMI between 01z and 02z. Strong/gusty northwesterly winds will continue through the remainder of the 00z TAF period. Gusts will generally be in the 25-30kt range tonight, then will increase to 30-40kt by Friday morning as low pressure rapidly deepens over the eastern Great Lakes. This will blow the light snow cover around quite efficiently, resulting in occasional reduced visbys. With only 1-3 inches of snow on the ground, limited the visby reductions to 5-6 miles. MVFR ceilings will persist through Friday afternoon. && .ILX WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning until 6 AM CST Saturday for ILZ027>031- 036>038-040>057-061>063-066>068-071>073. && $$ UPDATE...Barnes SYNOPSIS...Barnes SHORT TERM...Deubelbeiss LONG TERM...Deubelbeiss AVIATION...Barnes
National Weather Service Jackson KY
954 PM EST Thu Dec 22 2022 .UPDATE... Issued at 954 PM EST THU DEC 22 2022 The arctic air continues to push east this evening. The cold front is pushing toward our western counties this hour and perhaps a pre-frontal trough is noted with the precipitation moves east ahead of the front. The temperature drop behind the front is still lagging some and closer to the 925mb front. That said, we are in the 40s in eastern Kentucky and western Kentucky is already in the single digits. Did make some minor adjustments to bring in rain a little quicker given the pre-frontal trough. Outside this only minor edits were made to timing and temperatures as this seem to be on track. Will send these updates out and continue to monitor this unfolding winter storm. UPDATE Issued at 740 PM EST THU DEC 22 2022 We are watching the arctic air filter into the western part of the state this evening. The main surface boundary is coming through central Kentucky right now and arctic air filters in with the lagging 925mb front noted in the SPC mesoanalysis. The guidance is in decent agreement on timing of the cold air and has it in our western counties by around 10 to 11 PM and pushing east through the night. The differences that remain are just how cold we get and this has been lower in general from yesterdays forecast. Still seems like the HRRR and RAP are the colder outliers at this point. Either way we are talking about negative air temperatures and wind chills in the -20 to -30 range by early Friday morning. Overall the pace of this system and what we have in the grids are verifying well at this point. Main concern will be if we see colder temperatures sooner and how that would affect our snowfall totals. However, seems like there would be some tapering of the better moisture as it moves east leaving some uncertainty. This will have to be monitored through the evening shift for any possible need for upgrades. && .SHORT TERM...(This evening through Friday night) Issued at 524 PM EST THU DEC 22 2022 Late this afternoon an arctic cold front extended from MI south through western KY and on to the lower Mississippi Valley. A wave was traveling north along the front through IN. Ahead of the front, our temperatures were mostly in the upper 40s and lower 50s. The front and developing low were supported by an anomalously deep upper low dropping southeast from the north central CONUS. The surface low will explosively deepen as it wraps under the upper low tonight and Friday. The cold front will be propelled eastward through the forecast area tonight, and with the upper level support of the trough, bring precipitation. It will start out as rain, but quickly change to snow after the frontal passage. The snow may briefly come down heavy, especially if there are some elevated convective elements. The intense low pressure system will bring brisk winds, with gusts of 30-40 mph overnight into Friday. This will carry in the arctic air, with temperatures plummeting about 50 degrees, and much of this in drop occurring in just a couple of hours after fropa. The resulting wind chills will be dangerously cold, bottoming out at 25-35 below zero in most places on Friday morning. Flurries will continue at times on Friday and Friday night, but the cold will continue to be the main story. By the end of Friday night, the intense stacked low will still reside just north of the Great Lakes, and its circulation dominating most of the eastern half of North America. Temperatures will probably not warm out of the single digits on Friday, and fall to near zero on Friday night. Winds will ease a little, but still be strong enough to make wind chill a concern going into the weekend. Even though the Wind Chill Warning may be allow to expire on Friday, a Wind Chill Advisory will likely need to be extended into the weekend. .LONG TERM...(Saturday through Thursday) Issued at 320 PM EST THU DEC 22 2022 Key Concerns: 1. Bitterly cold temperatures persist throughout Christmas weekend. 2. Nighttime lows in the single digits above and below zero for most locations through Sunday night. 3. Wind chills of -10 to -20F (locally colder higher elevations) on Saturday morning. 4. Generally dry weather persists for the remainder of the week. 5. Temperatures moderate back to above normal levels by New Year`s weekend. The 22/12z model suite analysis shows an ~495 dam low over Southern Quebec at the start of period with an associated ~962 mb surface low reflection. This is counterbalanced by a strong 589 dam high off the Baja California coast and high amplitude ridging along/west of the Rockies. A narrow axis of surface high pressure ridging spans the High Plains of the US and Canada in the zone of subsidence ahead of the upper level ridge axis. Through the middle of the new workweek, the upper level pattern will deamplify with the deep 500H trough/low generally shifting toward Greenland while the subsiding 500H ridge moves out onto the Plains. There is NWP support, though varying spatially/temporally from model to model, for one last shortwave trough to rotate through the region on Tuesday as the upper low pulls away. Otherwise, look for ridging to increase over the Eastern CONUS later in the week while the next seasonably deep upper level trough descends the Rockies. At the surface, the pressure gradient will gradually weaken on Saturday and Saturday night as the high pressure to our west and low pressure to our north weakens. The high pressure shifts east to over the Ohio Valley by Monday morning. By Tuesday, the upper level shortwave drops through, but much of energy seems to split north and south of the Ohio Valley with little fanfare for eastern Kentucky. In fact, surface high pressure generally appears to remain over the Ohio Valley Tuesday before gradually shifting east to the Atlantic Seaboard on Wednesday through Friday. This will lead to a pleasantly moderating southerly return flow for the remainder of the week and year. Sensible weather will feature bitterly cold temperatures and wind chills lingering through the weekend. With 925 mb temperatures moderating to between -12 and -16C, expect highs in the 15 to 20 degree range on Saturday. Lingering low cloudiness may yield a few flurries through the day. Westerly wind gusts of 20 to 30 mph continue through the day. The coldest wind chills in the long-term period will be Saturday morning when they will flirt with 10 to 20 below zero at many locations. Saturday night lows will again be in the single digits, though if significant clearing occurs, sheltered valleys with snow cover could easily decouple and sink below 0F. Wind will be much lighter on Sunday with increasing sunshine and temperatures moderating into the upper teens north to mid 20s south. Looking ahead to the new work week, ample sunshine each day will be filtered by clouds at times. Temperatures continue to moderate several degrees each day with highs in the mid 20s to lower 30s on Monday, in the 30s (above freezing) for most on Tuesday, in the 40s on Wednesday and rising above 50 for most on Thursday. Nighttime lows will feature the typical ridge-valley split on every night. It will still be cold on Sunday night/Monday morning with upper single digits to lower teens on the ridges while the valleys sink back into the single digits to near 0F. That nocturnal ridge-valley temperature split likely carries through the remainder of the period with teens to lows 20s on Monday night, mid teens to mid 20s on Tuesday night and low 20 to low 30s on Wednesday night. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) ISSUED AT 658 PM EST THU DEC 22 2022 We are starting the TAF period with the mix of VFR and MVFR. A cold front continues to charge across the state this evening and will bring conditions down through the night. We will see rain showers initially with the surface front before quickly transitioning to snow by around 4Z at SME and cold air quickly moves east to transition to snow at SJS by around 7Z. Shortly after the transition we will see the potential for a period of heavy snow with LIFR conditions becoming probable at 90 to 100 percent chance based on the HREF during this time and probably in the VLIFR range with probability of less than a half mile visibility at 70 to 90 percent. The other issue will be strong winds of 15 to 20 knots sustained and 30 to 35 knot gusts shifting from south to west with the passage of the front. These snow showers will then transition to flurries by Friday morning. Overall after this, MVFR conditions will probably remain the story and the winds remain elevated into the day Friday, with the potential for continued blowing snow that could affect visibilities at times. && .JKL WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 9 AM EST Friday for KYZ044-050>052- 058>060-068-069-079-080-083>088-104-106>120. Wind Chill Warning from 1 AM to 4 PM EST Friday for KYZ044- 050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...DJ SHORT TERM...HAL LONG TERM...GEERTSON AVIATION...DJ
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
526 PM CST Thu Dec 22 2022 .UPDATE... Issued at 517 PM CST Thu Dec 22 2022 Updated for 00Z aviation discussion below. && .DISCUSSION...(This evening through Thursday) Issued at 221 PM CST Thu Dec 22 2022 KEY MESSAGES: - Life threatening conditions will arrive with increasing winds, decreasing wind chills, and significantly reduced visibility overnight. Stranded travelers could be susceptible to hypothermia and frostbite within minutes. - The worst conditions are expected Friday afternoon through Saturday morning, with gusts peaking at 45-50mph. Please do not travel. - A clipper system will bring light snow Sunday night into Monday morning, causing slick conditions for the Monday morning commute. - A pattern shift will warm temperatures significantly next week, with highs by Wednesday in the low to mid 30s. TONIGHT THROUGH SATURDAY MORNING... Compared to the overnight forecast, there have been a few changes but the overall weather picture has remained the same, in that unless absolutely necessary we do not advise traveling anywhere tomorrow through early Saturday. Conditions today have been proceeding as expected, with areas of western and southern Minnesota having been at or below 1 mile visibility for several hours already, with the stronger winds making their way eastwards. The gusts will start to pick up overnight especially, with the daylight hours tomorrow likely being the worst of the conditions for much of the area. Forecast soundings from CAMs have led to a small bump up in wind speeds and gusts expected tomorrow and Saturday, which despite an increase of only around 5mph has led to the Blizzard Warning being expanded to include the counties within and around the I-94 corridor in western Wisconsin. Momentum transfer winds of around 45-50kts are present at the top of the channel within RAP soundings with the HRRR only slightly lower, and while we likely won`t mix efficiently due to the blowing snow inhibiting diurnal mixing and some mid level clouds, we will still have plenty of wind to kick up the fresh snow. The stronger winds have also led to a slight decrease in the coldest wind chills, however this has not affected headline decisions as all of the area was already in either wind chill warnings or advisories. Conditions will slowly begin to improve on Saturday, but it will likely be during the day on Sunday before we truly see the end of the blowing snow concerns as winds above 15-20mph will be present through at least Noon on Christmas Day. As we have been saying numerous times throughout the last few days, this event has life threatening implications should you choose to travel and end up getting stranded due to both the difficulty of rescue operations and the dangerous wind chills that could result in frostbite within less than 10 minutes. Even in areas that are not within a Blizzard Warning, they are still going to be covered by a Winter Storm Warning, so do not let your guard down at all during the day tomorrow no matter where you are located. SUNDAY THROUGH NEXT WEEK... Christmas Day will see rapid improvement, especially during the second half of the day, as winds decrease below 10mph with high pressure beginning to more directly overhead. This will result in one more cold morning with below zero low temperatures, however with much weaker winds, our wind chills will only be in the teens below zero. Another clipper system is looking probable late Sunday through early Monday which could bring a hit of light snow for much of the area, currently favoring western and southern Minnesota as the clipper dives southeastwards. We could end up with a couple of inches of light snow for the area, however at this point that just adds another small amount to our currently generous snowpack. Our pattern is going to shift significantly as we head into next week, with temperatures slowly increasing such that highs in the low to mid 30s are possible by Wednesday, increasing further heading into next weekend. This pattern does look to persist into the new year, with warmer than normal conditions favored through the middle of the first week of January. Along with the warmer temps, there does appear to be another potential system moving towards the region later next week, and with temperatures hovering near freezing at times could result in another sloppy event with multiple precipitation types. For now, we have left that out of the forecast as there are more immediate concerns than a day 7 freezing rain forecast, however as we get a bit closer expect more details and discussion revolving around the mixed precipitation potential. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 517 PM CST Thu Dec 22 2022 Northwest winds will continue to increase overnight, leading to blowing snow through much of the period. Wind gusts will generally range from 20-30 kts tonight, increasing to 30-40 kts overnight & peaking near 40-45 kts during the day tomorrow. Blowing snow will be a concern through the period, with IFR/MVFR visibility tonight becoming predominately IFR tomorrow as the winds increase. Several hours of visibility below 1SM is possible tomorrow, especially across western and southern Minnesota. KMSP...High confidence in the wind speeds forecast, but low confidence on just how low visibility may drop with the blowing snow. the trend has been towards pushing back the gusty winds & blowing snow later and later, with MVFR/IFR vis now not expected until late tonight. Several hours of IFR visibility is likely beginning tomorrow morning, especially from mid-morning onwards as wind gusts peak up to 45 kts at times. Visibility lower than 1SM can`t be ruled out if the blowing snow potential is maximized. /OUTLOOK FOR KMSP/ Sat...AM MVFR/IFR and BLSN. Wind NW 20G30 kts. Sun...VFR. Wind SW 5-10 kts. Mon...VFR. Wind NE 5-10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...Wind Chill Warning until noon CST Saturday for Brown-Chippewa- Douglas-Kandiyohi-Lac Qui Parle-Martin-Pope-Redwood-Renville- Stevens-Swift-Watonwan-Yellow Medicine. Blizzard Warning until 6 AM CST Saturday for Carver-Dakota-Douglas- Goodhue-Rice-Scott-Stearns-Todd-Wright. Wind Chill Advisory until 6 PM CST this evening for Carver-Rice- Scott-Stearns-Todd-Wright. Wind Chill Warning until noon CST Saturday for Blue Earth-Carver- Faribault-Freeborn-Le Sueur-McLeod-Meeker-Nicollet-Rice-Scott- Sibley-Stearns-Steele-Todd-Waseca-Wright. Wind Chill Advisory until noon CST Saturday for Anoka-Benton- Chisago-Dakota-Goodhue-Hennepin-Isanti-Kanabec-Mille Lacs- Morrison-Ramsey-Sherburne-Washington. Winter Storm Warning until 6 AM CST Saturday for Anoka-Benton- Chisago-Hennepin-Isanti-Kanabec-Mille Lacs-Morrison-Ramsey- Sherburne-Washington. Blizzard Warning until 6 AM CST Saturday for Blue Earth-Brown- Chippewa-Faribault-Freeborn-Kandiyohi-Lac Qui Parle-Le Sueur- Martin-McLeod-Meeker-Nicollet-Pope-Redwood-Renville-Sibley- Steele-Stevens-Swift-Waseca-Watonwan-Yellow Medicine. WI...Wind Chill Advisory until noon CST Saturday for Barron-Chippewa- Dunn-Eau Claire-Pepin-Pierce-Polk-Rusk-St. Croix. Winter Storm Warning until 6 AM CST Saturday for Barron-Polk-Rusk. Winter Storm Warning until 6 AM CST Friday for Chippewa-Dunn-Eau Claire-Pepin-Pierce-St. Croix. Blizzard Warning from 6 AM Friday to 6 AM CST Saturday for Chippewa- Dunn-Eau Claire-Pepin-Pierce-St. Croix. && $$ DISCUSSION...TDH AVIATION...ETA
Area Forecast Discussion
National Weather Service Springfield MO
613 PM CST Thu Dec 22 2022 Key Messages: 1. A band of moderate to heavy snow east of the Highway 65 corridor will continue to push through the area this afternoon, reducing visibilities to a quarter mile at times. Patchy blowing snow likely continues tonight. 2. Flurries/light lake effect snow possible tonight. 3. Historic and dangerously cold wind chills Thursday into Saturday. Wind Chill Warning in effect areawide tonight into Saturday morning. 4. Low-end light snow chances Sunday night into Monday with passage of clipper system. 5. A sharp warming trend will rebound temperatures to near or above normal early next week. .SHORT TERM...(This evening through Friday) Issued at 152 PM CST Thu Dec 22 2022 Radar returns currently show the band of heaviest snow east of the Highway 65 corridor this afternoon. RAP data continues to indicate 700 mb frontogenesis coinciding with strong omegas aligned with this band, so intensity will likely be maintained at least. Snow will end from west to east throughout the afternoon. Reports and observations received thus far show storm total snowfall amounts of 1-3" areawide. Patchy blowing snow will be possible intermittently behind the main band of snow this evening into the overnight hours. The Winter Storm Warning will likely be trimmed early as the accumulating snow ends. Lake effect snow will also be possible near the larger lakes of our CWA. With lake temperatures in the mid 30s, very cold air above it, and strong unidirectional northwest winds over a relatively large fetch will result in lake-induced cape values above 500 J/kg according to Bufkit data. This could produce some flurries or even snow showers this evening and tonight. The primary hazard tonight, however, will be the dangerously cold wind chills. Temperatures will continue to drop this evening in the single digits below zero. With the persistent strong winds, wind chills will fall into the -25F to -35F range areawide. The Wind Chill Warning remains in effect until Saturday morning. .LONG TERM...(Friday Night through Thursday) Issued at 152 PM CST Thu Dec 22 2022 Friday - Saturday: Bitter cold temperatures will continue as the Arctic air mass spreads southward across the central US. Most of our area will likely see afternoon highs remaining below double digits on Friday with wind chills around -20 to -30 as northwest winds persist over the region. On Friday night, winds will gradually weaken as the surface high settles over the southern Plains. With clear skies and a snowpack over the area, we could see temperatures fall back below 0, especially over our western counties. Slightly warmer temperatures are expected on Saturday, but still only rising to around 20 degrees and winds continuing to decrease. Sunday - Monday: Surface winds will gradually shift to the southwest on Sunday and help warm up the area but still expect highs to remain below freezing. Upper level northwest flow may bring a clipper system across the region Sunday night into Monday, which will bring increased cloud cover and possibly some light snow/flurries. Tuesday - Thursday: The upper level pattern will gradually shift to more of a zonal, then southwesterly flow. This should give us a decent warm-up, with a few locations rising into the 50s to near 60 degrees by Thursday afternoon. WPC cluster analysis are pretty consistent with the warming, but inconsistent with respect to timing. So we have decent confidence on the warm-up, but lower confidence on the timing. We will also be watching forecast trends on a developing storm system that could impact the region late next week and into the weekend. At this time it looks like more of a thunderstorm/liquid precipitation event. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 552 PM CST Thu Dec 22 2022 With the exception of some flurries or light snow at the Springfield terminal, due to lake effect snows off of Stockton Lake, accumulating snow has ended. Ceilings should improve but visibilities will be impacted by blowing snow with northwesterly winds gusting from 25 to 40 mph at time. The strong gusty winds will continue through the night and into Friday. && .CLIMATE... Issued at 245 AM CST Mon Dec 19 2022 (Vichy-Rolla had missing data in 1989) ***Thursday December 22nd*** Record Low Temperatures Springfield -15 in 1989 Joplin -15 in 1989 West Plains -13 in 1989 Vichy -5 in 2000 ***Friday December 23rd*** Record Low Temperatures Springfield -16 in 1989 Joplin -15 in 1989 West Plains -12 in 1989 Vichy -4 in 1963 Record Lowest Maximum Temperatures Springfield 5 in 1983 Joplin 3 in 1983 West Plains 10 in 1989 Vichy 12 in 1990 ***Saturday December 24th*** Record Low Temperatures Springfield -10 in 1983 Joplin -10 in 1983 West Plains -13 in 1989 Vichy -1 in 1990 && .SGF WATCHES/WARNINGS/ADVISORIES... MO...Winter Storm Warning until midnight CST tonight for MOZ055- 066>068-071-077>079-082-083-088>090-094-097-098-106. Wind Chill Warning until noon CST Saturday for MOZ055>058- 066>071-077>083-088>098-101>106. KS...Winter Storm Warning until midnight CST tonight for KSZ073-097- 101. Wind Chill Warning until noon CST Saturday for KSZ073-097-101. && $$ SHORT TERM...Didio LONG TERM...Terry AVIATION...Hatch CLIMATE...Perez