Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/22/21

Area Forecast Discussion
National Weather Service Gaylord MI
1025 PM EST Sun Nov 21 2021 .UPDATE... Issued at 1025 PM EST Sun Nov 21 2021 Cold front has pushed east of Northern Michigan late this evening. CAA has begun in earnest...quickly activating over-lake instability. Last vestiges of synoptic precip has exited east of our CWA with the front...transitioning our ongoing precip event to a multi-band W/NW flow lake effect snow event. Tight pressure gradient behind the front has resulted in a rapid strengthening of winds...gusting as high as 40-50 mph at times with the highest winds along our Lake Michigan shoreline areas. PLN gusted as high as 46 kts just before 8 pm. Strong winds are pushing lake snow bands further inland as expected...with at least some snow falling across almost all of our CWA. Reduction to vsbys due to falling and blowing snow has modest so far...with most surface obs reporting vsbys at or above 1SM even within some of the heavier snow showers. Still expect Eastern Upper Michigan will see the development of heavier snow bands overnight thanks to high inversion heights (around 13 kft) and better low level moisture availability. Inversion heights are much lower across Northern Lower the 5-7 kft range...which should translate to significantly less potential for accumulating snow. See no reason to deviate from expected snow amounts and ongoing headlines. Will maintain the Winter Storm Warning/Winter Wx Advisory for Chippewa county where some locations could see up to a foot of new snow overnight into Monday as a result of deep lake convection... targeting far Northern Chippewa county for highest snow amounts. Will also maintain the Wind Advisory for all of our Lake Michigan shoreline counties thru the balance of the night. && .NEAR TERM...(Through Tonight) Issued at 351 PM EST Sun Nov 21 2021 ...Major blast of winter on the way for eastern upper MI... High Impact Weather Potential: Locally very high. Heavy lake effect snow with near blizzard conditions in parts of eastern upper MI tonight. Gusty winds, strongest this evening. A quick burst of snow this evening in spots and/or icy roads developing. 1000mb surface low is just w of James Bay. A sharp and well-defined cold front extends south across eastern Superior and down the long axis of Lake MI. Gusty winds usher in strong cold advection immediately behind the front. This November gale has a large number of forecast concerns, centering on wind, lingering synoptic precip that goes from rain to snow, and lake effect. Presently, warm advection ahead of the cold front has boosted temps into the upper 30s to mid 40s across northern MI. Developing precip shield is all liquid, with some shallow convective elements emerging recently over northern lower MI. This warm air and liquid precip is not long for this world, with the cold front entering nw lower MI and western Chip/Mack now, and exiting over Lk Huron by 7 pm. A number of wind gusts to circa 40kt/45mph have been seen over WI, though diurnal mixing (aided by some outright sunshine) is aiding wind production there. A solid isallobaric component will be present for us to aid wind production, as will mixing over the increasing unstable lakes. Nam BUFR soundings still support circa 45mph gusts in susceptible coastal areas near Lake MI. No significant changes made to wind headlines (at least since Mackinac Co was added earlier). Strong cold advection will allow precip to transition to snow before transitioning further to lake effect. A quick burst of snow squall- type activity is expected between 5 and 9 pm, where synoptic forcing best intercepts increasing overlake instability. This is of greatest concern over far northern lower MI, between roughly PLN and GLR inclusive. A quick inch of wind-blown snow, along with strong winds, will produce a brief period of potentially hazardous travel conditions. Elsewhere, wet roads will become icy this evening. By 11pm, we will transition to pure lake effect snow. 850mb temps are presently circa -4C, but we will drop about 10C by morning. Inversion heights on Lk Superior start out near 12k ft mid/late evening, then lower closer to 8k ft overnight. A potent 500mb shortwave trof will close off as it passes north of the Sault tonight. That will keep more synoptic moisture available over Superior, much more so than even over northern Lks MI/Huron. Hi-res guidance is near unanimous in developing a dominant band over central/eastern Superior, with a slightly wobbly wnw to nw fetch sending it into the vicinity of the twin Saults overnight. Lake- induced CAPE values are in high triple digits, and the DGZ is very well-placed in the layer of max ascent to maximize dendrite production and snow-liquid ratios. (Though we will have enough wind, and associated fracturing/compaction of snowflakes, to hinder ratios.) Initial guidance from WPC gave just about an inch of liquid QPF in the 6hr window ending at 12Z/7am Monday, in a band over ne Chippewa Co. Have toned that down, just to give some snowfall accums that I can sort of live with. Have also adjusted the position of the band ne-ward a touch, to give the HRRR at least a bit of credence. Recent runs of that model clobber northern Sugar Isl tonight, while allowing the Sault to escape the worst of it. But that said, there are still some very large accums in the forecast for tonight (and into Mon morning), over the Sault and the north half of Sugar Isl. Someone is getting a foot of snow (at least) tonight, though it could conceivably end up being mostly Canadians. There is also a very tight snowfall gradient toward lesser amounts as you head sw from the Sault. Upgrading central Chippewa Co to a warning is obvious. The dominant band expected overnight will produce very high accums and near- blizzard conditions. Note that (thankfully) the strongest winds will occur this evening, before the best lake effect gets set. Adding se Chippewa to an advisory is also reasonable, with the stronger winds allowing the lake effect snow bands to penetrate more easily into the Drummond Isl area. Western Chippewa was a tougher call, with weaker but still reasonably impressive banding expected to poke into Hulbert/Strongs. But still figure that there are enough snow and winds to produce winter storm-level impacts there. So upgraded that zone to a warning as well. Lake effect snow should be far, far less potent for northern lower MI. Deeper moisture is not available, and inversion heights (8k dropping to 5k ft) and lake-induced CAPE (mid triple-digits) are sharply lower. Localized 1-3" accums expected. Min temps tonight mainly low-mid 20s. Wind chills will drop well into the teens. && .SHORT TERM...(Monday through Wednesday) Issued at 351 PM EST Sun Nov 21 2021 ...Lake effect continues through Monday... High Impact Weather Potential...Moderate. Accumulating snow continues through Monday, possibly lingering into Tuesday morning. Pattern/Synopsis...The upper level pattern begins the week with anomalously strong troughing stretching from Hudson Bay down through the Tennessee Valley...and strong ridging over the western half of the CONUS. A strong jet 120-140kt exists between these...with cold air driving southeast across the lakes. The pattern remains progressive however, with troughing moving off the east coast and ridging moving into the Great Lakes by late Tuesday. The next system, a positively tilted trough, moves across the Rockies heading into mid-week...set to bring more showers just before/heading into Thanksgiving. Forecast/Details...We remain in cold cyclonic flow with lake effect ongoing through the day Monday. DeltaT`s remain aoa 20C with inversion heights 8-9 kft and plenty of low level moisture to be had across Ern Upper. Snow (likely banded per hi-res guidance) will still be going strong, with a dominant band expected to still be chugging along from lake Superior, across Ern Upper into Nrn Lake Huron. With boundary layer winds expected to be 290-300 deg believe Nrn Chippewa county, including the SOO, will see the heaviest accumulations with the snow band wavering over them the longest... Nrn Lower will still have ongoing lake effect snow, just to a lesser extent in intensity, with inversion heights up around 7 kft and drier mid-levels above the lake convection. Overall expect additional accumulations of 3-5" across portions of western Chippewa/Mackinac counties, with the SOO receiving more, upwards of 6 or 7 inches through the day, with lower amounts (1-2") across portions of Nrn Lower. Although winds will start the day gusty they will be slowly diminishing with the slackening gradient through the day. Regardless, blowing snow is still possible, especially closer to the Lake Michigan shore. As we head through the night the environment becomes increasingly less-favorable for robust LES, with inversion heights lowering, rapidly loosing saturation through the DGZ, and winds weakening and backing slightly through the night. Surface ridging moves overhead early Tuesday and we get into southwest return flow with 850mb temperatures rising through the day. Overall a quiet period with temperatures moderating into the upper 30`s/lower 40`s. Shortwave ridging pushes east of us Wednesday with an elongated positively tilted trough approaching from the west. A weakening surface low will be trekking into Ontario across western Lake Superior through the day, keeping us in gusty southerly flow. WAA and moisture advection occur throughout the day (PWAT`s get up to around 0.70" which is at least 1 St. Dev above normal for late November.) However, believe rain chances will hold off until the afternoon and possibly even even as the columns takes a bit to saturate, and relatively little forcing is expected ahead of the incoming system. Forecast afternoon highs are expected to be milder (in the mid to upper 40`s) but the gusty winds will make it feel a bit brisk. .LONG TERM...(Wednesday night through Sunday) Issued at 351 PM EST Sun Nov 21 2021 High Impact Weather Potential...Minimal for now. Watching Wed/Thurs system Pattern Synopsis/Forecast...Heading into Thanksgiving the aformentioned western trough crosses the upper Great Lakes...with its associated surface low following suit into southeast Ontario. This will bring a period of rain/snow showers Wednesday night, changing over to snow through Thanksgiving Day as colder air filters in on northwest winds behind the system. Additional precipitation chances are expected late week through the weekend, as a series of waves rotate down through the Great Lakes. The best snow potential looks to be associated with a clipper dropping through the Great Lakes on Sunday. Overall no huge accumulating snow events expected late week/through the weekend with highs generally ranging through the 30`s. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 611 PM EST Sun Nov 21 2021 A period of synoptic snow along a fast-moving cold front will drop conditions to IFR this evening...with the lowest vsbys and cigs across far Northern Lower Michigan and the interior/higher elevations of Northern Lower Michigan where precip will switch over to snow first. Strong CAA behind the cold front will produce lake effect snow showers later this evening into Monday... targeting our typical snowbelt areas of Northern Lower Michigan directed by W/NW flow. Greatest snow chances and worst conditions (IFR) will generally be between PLN and TVC as lake snow banding develops tonight and persists into Monday. Strong W/NW surface winds of 20 to 30 kts will occasionally gust to 35 kts... especially along the Lake Michigan shoreline areas of NW Lower Michigan. && .MARINE... Issued at 351 PM EST Sun Nov 21 2021 Strong cold front is crossing northern Lake MI, with very gusty w to nw winds behind it. Gales expected on all waters tonight and into Monday morning. Only gradual improvement after that. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY until noon EST Monday for MIZ088. WINTER STORM WARNING until 7 PM EST Monday for MIZ086-087. WIND ADVISORY until 5 AM EST Monday for MIZ016-020-021-025-031- 095>099. LH...GALE WARNING until 10 AM EST Monday for LHZ345>349. LM...GALE WARNING until 10 AM EST Monday for LMZ323-341-342-344>346. LS...GALE WARNING until 10 AM EST Monday for LSZ321-322. && $$ UPDATE...MR NEAR TERM...JZ SHORT TERM...STJ LONG TERM...STJ AVIATION...MR MARINE...JZ
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
549 PM CST Sun Nov 21 2021 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...The TAFs have been simplified a bit to reflect the overnight passage of a cold front. The timing of the showers in the TAFs are based on the HRRR model. Overall, VFR is expected at the aerodromes through the next 24 hours. && .PREV DISCUSSION... /issued 308 PM CST Sun Nov 21 2021/ SHORT TERM (Tonight through Monday Night): The main story in the short term revolves around the cold front expected to pass through Deep South Texas late tonight into early Monday morning and the potential for flooding with the showers and thunderstorms expected ahead of and along the frontal boundary. Ahead of the front, southeasterly winds will continue to advect low to mid level moisture across the area, increasing precipitable water to 1.4 to 1.7 inches. With ample moisture and moderate instability (CAPE near 1000 to 1500 J/kg) some of these showers and thunderstorms could be efficient rain producers and lead to the threat of flash flooding. On top of this, soils are still relatively saturated due to recent rains, increasing the flooding potential for areas that receive storms with higher rainfall rates. Most of the models have the higher rainfall amounts west of I-69E with totals between 1.5 to 2 inches, but locally heavier rainfall will possible. As such, a Flood Watch is out from 6 PM tonight to 6 AM Monday morning. Then most of the rain will clear out by mid to late morning as the front pushes south of the Rio Grande and ushers in a drier, more stable airmass. Decent cold air advection behind this front will cause high temperatures to drop 10 to 15 degrees from today to Monday, with highs near 70 degrees. With the front passing through early Monday morning, cold air advection behind the front will compete with weak diurnal heating across areas that will see more sun...maintaining a small temperature variation during the day tomorrow. Some locations may even see their high temperature early in the morning before the colder air moving in drops/maintains near stable temperatures for the rest of the day. Overnight Monday night, the cloud cover will begin to dissipate and temperatures will drop into the upper 40s for the ranchlands, mid to upper 50s in the Valley, and the 60s along the immediate coast. LONG TERM (Tuesday through Sunday): As the front exits the area for Tuesday, a large mid-level ridge moves over the central United States and Texas for Tuesday and Wednesday. This ridge will bring southeasterly flow to the CWA, warm air advection, and give us a break from the rain for a couple of days. Beginning Wednesday morning, a couple of positively tilted trough formations begin to strenghtens across the western portion of the country. Wednesday will be the warmest day of the week with high temperatures in the mid 80s and will also be breezy as the troughs move into western Texas and strengthen the surface pressure gradient over the CWA. By Thursday morning, a cut-off low begins to form over the Baja Peninsula separating itself from the stronger low over the northern Midwest. This cut-off low pulls 500mb vorticity completely across the central United States. The energy being pulled further south will help bring the cold front all the way down to Deep South Texas for Thanksgiving Day. As far as precipitation goes, the models still haven`t quite agreed on the location or exact timing, but Deep South Texas can expect to see rain before the actual front moves through. However, they both still currently show the eastern CWA receiving the best chance for rain during the day Thursday. Looking at forecast GFS soundings for 12z-00z Thursday/Friday, PWATs are still staying steady around 1.5 to 1.8 inches. The GFS/ECMWF are in slight disagreement regarding the initial timing of the front. The GFS has the winds shifting north Thursday evening while the ECMWF has the front coming through a little later around midnight instead. The low over Mexico eventually closes itself off by Saturday leaving a coastal trough positioned over the Gulf Waters into the weekend. This trough will give us a slight chance of rain over the coastal counties and gulf waters for Saturday and Sunday. The WPC QPF forecast also has their 24-hour Day 5 QPF outlook showing 1.25 to 2.00 inches expected especially for the Rio Grande Valley valid for 00z Friday to 00z Saturday. Thursday`s high temperatures will still be near seasonal but once the front moves through, we can expect highs in the low 70s and lows in the lower 50s with a northerly wind for the rest of the long term period. MARINE (Tonight through Monday Night): Marine conditions will remain favorable through this evening, but will then quickly deteriorate behind the cold front expected to pass through early Monday morning. Showers and thunderstorms will form ahead of and along the frontal boundary, leading to additional hazards with the potential for lightning, strong wind gusts, and reduced visibility. Small Craft Advisories are in effect from early Monday morning into Monday evening. Then winds and seas will gradually subside Monday night. Tuesday through Sunday: Winds and seas will still be elevated following the front on Monday. As a ridge moves into the area on Tuesday, seas will begin to improve but then are elevated once again as the troughs develop over the Plains and breezy southeasterly flow returns. Southeasterly flow dominates until Thanksgiving Day when a front pushes through the area. This front will increase our seas to 5 to 8 feet overnight Thursday into Friday and stay elevated through the long term period. Small Craft Advisories may be needed as early as Wednesday morning. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 64 71 60 76 / 60 40 0 0 BROWNSVILLE 64 72 58 79 / 60 50 0 0 HARLINGEN 61 70 54 78 / 70 40 0 0 MCALLEN 61 70 54 78 / 80 50 0 0 RIO GRANDE CITY 59 71 52 78 / 90 30 0 0 SOUTH PADRE ISLAND 68 72 67 74 / 60 50 10 0 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...Flood Watch through late tonight for TXZ248>250-252-253-353. GM...Small Craft Advisory from 6 AM to noon CST Monday for GMZ130-132- 135. Small Craft Advisory from 3 AM to 6 PM CST Monday for GMZ150-155- 170-175. && $$ This product is also available on the web at:
Area Forecast Discussion
National Weather Service State College PA
953 PM EST Sun Nov 21 2021 .SYNOPSIS... A sharp cold front will cross the Commonwealth overnight, ushering in a couple of days of lake effect snow showers lasting Monday into Tuesday. Conditions will greatly improve by midweek. Wednesday and Thanksgiving Day both look dry. However, another strong cold front looks like it will blast through PA on Friday with rain arriving Thursday night. More blustery weather is then expected for the rest of the long weekend. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... Broken band of light to moderate rain showers extends from the Pocono Plateau through the South Central Mountains late this evening, along and ahead of the first of two cold fronts to cross the area overnight. Front #1 tracks to the east of the Lower Susq by or shortly past midnight. Front #2 delivers a real cold punch in the predawn hours, and despite the lowering inversion overnight, there`s sufficient lift and a ribbon of instability along it to produce a line of snow showers as it passes between 05z to 08z across NW and NC Mountains. Instability and moisture wane as one moves farther south along the Allegheny front, so we think generally weakened snow showers and flurries will accompany the front in the predawn hours of the morning over the Central Mountains. A snow squall can`t be ruled out farther N and W, but instability is somewhat lacking and inversion is generally below 5kft at BFD per latest RAP soundings. We`ll still need to keep an eye on the development of convection along the arctic front as robust moisture flux off of the warmer lakes this time of year can produce hybrid events. Any snow accumulations should stay below an inch over the NW third of the area, and little to no snow accums elsewhere as the temps will still be a little too mild at sunrise for anything to stick. Mins in the upper 20s N and around 40F in Lancaster and Harrisburg. The wind could gust into the 20s along and behind the second front. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... Snow showers associated with the arctic front should be gone around sunrise, but it could take until 13-14Z to pass thru LNS. The wind then picks up everywhere as we mix thru the day. Gusts inn the 20s will be widespread with a 30+ gust here and there. LES is a certainty with the temps at the top of mixed flow off the lakes dropping into the perfect -12C to -17C dendritic snow growth zone. The fetch is not the longest fetch for much of the time. Will continue to play the climo card and paint the highest snow totals over NW Warren Co and along the NY border toward Potter and Tioga Counties. The eventual totals through Tuesday morning will get between 3-6 inches. But, it looks unlikely that any 12-hr period will go AOA 3" for accums. The best conditions look to be Monday afternoon and Mon night. Will hold off on an advy for the time being, but could certainly see one being hoisted for Warren/McKean Cos by later shifts. Temps will only rise 3-5F thru the day Mon. We`ll drop to 20-26F for most of the area Mon Night. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... Little change with evening update. Blustery and colder conditions will continue for Monday night and Tuesday, as very cold air plummets south across the region with passage of a deep upper trough and H85 temperatures cooling to around negative 10C by late Monday night/early Tuesday morning. Snow squall potential looks to have backed off overall over the past day or two as moisture aloft quickly dries out, but will nonetheless see some snow showers continue across portions of the Alleghenies. Lake effect snow showers look to kick up in this regime, especially later Monday into early Tuesday as the coldest of the air arrives and lapse rates steepen downwind (southeast) of Lake Erie. Several inches of accumulation are likely in the favored snowbelt of northwest Warren County, with lesser amounts farther southeast, mainly across the Alleghenies into the Laurel Highlands. Northwest winds will gust up to 35 mph at times. All medium range guidance lifts the aforementioned upper trough out by later Tuesday, with surface high pressure building in for midweek. Thus, expect lingering lake effect snow showers to taper off over the Alleghenies Tuesday afternoon, with clearer and milder conditions by Wednesday. However, the setup could be favorable for a very cold Tuesday night with the surface ridge over the state. After a dry period of weather Wed and Thanksgiving Day, focus then shifts to the trailing cold front which could approach Thursday night. So far it looks like this front will bring mostly rain showers Thu night. Post frontal cold temperatures, gusty winds, and snow showers appear in the offing for Friday, with lake effect snow showers possibly lingering into the weekend. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... Another round of showers will move across central PA this evening as a cold front moves in from the west. Generally seeing VFR conditions in the east with brief periods of MVFR due to lower cigs across the central airspace. IFR cigs however over the north (BFD) and west (JST) will likely persist through the night. Cold front will diminish precip tonight, but lower cigs persist into early Mon, especially over the west. Pattern will transition to gusty westerly flow with colder air bringing lake effect snow showers and lingering MVFR/IFR conditions across western/northwestern airspace Monday into Tuesday. Outlook... Mon-Tue...MVFR/IFR west with -shsn. VFR central/east. Gusty winds 20-25kt from 280-320 degrees. -shsn and winds fade Tue. night. Wed-Thu...VFR. No sig wx Thu night...Showers/restrictions possible with next frontal system. Fri...Breezy NW flow, snow showers mainly NW. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Lambert/DeVoir/Dangelo NEAR TERM...DeVoir/Dangelo SHORT TERM...DeVoir/Dangelo LONG TERM...DeVoir/Fitzgerald/Colbert AVIATION...RXR/Travis
Area Forecast Discussion
National Weather Service Des Moines IA
1139 PM CST Sat Nov 20 2021 ...Updated for the 06z Aviation Discussion... .DISCUSSION.../Tonight through Saturday/ Issued at 259 PM CST Sat Nov 20 2021 Key Messages: - Light Precip Far Northern Iowa This Evening - Gusty Winds Sunday; Considerable Cool Down - Cold Monday, Warmer Tuesday into Wednesday Tonight and Sunday: A few short-wave perturbations have been moving across the area through the general zonal mid-level flow pattern across the region. There has been enough moisture in the mid-levels to result in cloud cover, especially north of U.S. Hwy. 30. Slight chance POPs with sprinkles/flurries have been left in the forecast through the middle part of this evening for northern portions of the forecast area, mainly where the clouds are expected to persist to with stream of mid-level moisture. The HRRR along with other CAM solutions continue to depict weak precipitation across this area. The main challenge that hydrometeors will face is a dry layer present in the lowest 1 km of the troposphere. While radar has been showing weak reflectivity along and north of U.S. Hwy. 20 this afternoon, there have not been any reports thus far at the surface of rain or light snow. Most hydrometeors appear to be evaporating. With the weak forcing and some moisture though, a few may be able to survive, especially if saturation is able to sneak down below 700mb. If any light precipitation is observed, accumulations are not expected to be much, if any at all. There is a weak boundary that has been analyzed from north of Omaha to around Mason City at of 18z, mainly denoted by a northerly wind shift. The cloud cover in the area has kept temperatures across the north slightly cooler when compared to southern Iowa temperatures, not so much the boundary influence. There is a slightly stronger short-wave trough currently moving into the eastern Plains that is quickly pushing the surface high pressure over Minnesota eastward. A strong trough further north in Canada associated with a surface cyclone is also present, and is quickly catching up with southern short-wave. As the first, more southern short-wave moves across Iowa, CAA will begin in the 925-700mb layer, and will also drastically increase flow. This will assist in creating a deeper mixed layer across the region, with winds at the top of it around 40-45 MPH. As a result, Sunday afternoon is expected to be windy, with gusts 35 to 40 MPH likely across the north. A few spots may see 45 MPH gusts. The current forecast is for winds to mostly remain below headline criteria, thus no wind headline has been issued for Sunday afternoon. Later in the day on Sunday, the short-wave trough digging out of Canada will catch up with the southern wave, and will result in a trough a low pressure at the surface as well. This will accelerate a stronger cold front across the area Sunday afternoon and into evening. This will drastically decrease temperatures, especially after 00z. This may start to hit northern reaches of the forecast earlier in the afternoon. If the front slows down by a few hours, southeastern and eastern Iowa may be able reach mid 50s temperatures again Sunday afternoon. The arrival of the surface trough will maintain a stronger pressure gradient, especially with a strong high pressure behind the front, thus maintaining gusty winds into evening. Temperatures Sunday Night into Monday morning should hit well below freezing. Despite the strong convergence with this system, dry air will quickly move in behind it, and will limit precipitation potential as it moves through the area. Flurries may develop in some areas, but for now are not in the official forecast. Monday and Beyond: As the trough propagates and deepens across the Great Lakes Region, the pattern becomes further amplified by a mid-level ridge over the western third of the CONUS. On Monday this will leave Iowa in an area of strong northwesterly flow and plenty of AVA. This will promote subsidence and continue strengthen the surface high pressure across the area, and will continue to push cold air into the region. Temperatures will struggle to make it out of the upper 30s on Monday in this pattern. The propagation of the ridge axis though will make steady progress though, as another trough makes landfall along the western CONUS. By Tuesday, this will shift surface to 850mb flow south-southwesterly, and create a WAA regime across and east of the Missouri River Valley. This ridge axis should then push eastward of the Mississippi River Valley by late evening on Tuesday, as the short-wave digs into the Rockies. This will result in cyclogenesis in the Front Range, and quickly pushes the cyclone into the Central Plains. In response, low-level flow will remain southerly for much of Tuesday and into Wednesday. The center of this cyclone is still looking to track northwest of the forecast area, keeping most locations in the warm-sector at least through Tuesday Night. Wednesday high temperatures will depend on the propagation speed of the cold front. Beyond Tuesday Night/ Wednesday morning, there are now some discrepancies between GFS/ECWMF deterministic solutions, as well as the respective ensemble members. The deterministic GFS has started to expand the Gulf Moisture a bit further west and arriving in southeast portions of the forecast area, compared to runs from yesterday that kept it away. However, the GEFS members remain split, with most members still keeping the higher QPF southeast of the forecast area. Deterministic ECMWF brings a little bit more moisture westward, but not as drastic as the GFS. NBM has introduced some POPs for southeast and eastern Iowa Wednesday into Thursday, and have not been substantially changed from that in the official forecast. Currently, temperatures appear to be warm enough for an all rain precipitation type for southeastern and eastern Iowa should precipitation actually occur. Overall, Holiday Travel impacts across Iowa look minimal at this time. Areas east of the Mississippi River Valley may have some, as this is where the higher moisture is still favored. Beyond Thursday, northwesterly flow once again arrives and will provide cooler air across the area and into next weekend. && .AVIATION.../For the 06Z TAFS through 06Z Sunday night/ Issued at 1138 PM CST Sat Nov 20 2021 Sprinkles/flurries are expected overnight in central Iowa mostly from VFR ceilings. Winds remain light and variable overnight. Cold front moves through the state in the morning with mostly VFR conditions during the day. There is an outside chance of MVFR ceilings in northeast portions of the forecast area late morning/early afternoon where some higher RH values cross the area. Otherwise surface wind gusts of 25+kts are likely behind the front. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...Krull AVIATION...Cogil
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1259 AM EST Sun Nov 21 2021 .AVIATION... Mid clouds around 10kft will continue to stream into the area tonight ahead of the next system to impact the region Sunday. The strong parent low will be well to the north while a weaker surface low will track through the Ohio Valley. This low will result in increasing moisture streaming into the area, lowering CIGS this afternoon and bringing a period of light rain to the region. Best chance for rain will be across the Detroit area while chances lessen farther north. CIGS and possibly VSBYs will drop to MVFR this afternoon with the rain and deeper moisture. A cold front will then sweep across the area around 00Z tonight, bringing strong westerly winds to the area. Winds will be strongest between 00-06Z with gusts nearing 35 knots. Winds will then weaken slightly the rest of the night maxing out closer to 25 knots. .DTW THRESHOLD PROBABILITIES... * Moderate confidence in cigs aob 5000 Sunday afternoon * High confidence in precip type as rain Sunday afternoon && .PREV DISCUSSION... Issued at 358 PM EST Sat Nov 20 2021 DISCUSSION... The plume of mid level moisture and elevated instability proved worthy of the challenge posed by a formidable layer of dry air in the low levels. This resulted in pockets of light rain and brief flurries after impressive work was done from the starting point shown in the 12Z DTX sounding. The mid level moisture axis now moves eastward this evening. Low level dry air is reinforced by westerly flow from the IA/MO/IL vicinity tonight while mid and high clouds thin enough for partly cloudy conditions at times. A late return of thicker high clouds, along with light but persistent south wind, helps keep temperatures above freezing through sunrise Sunday. High clouds late tonight precede the next low pressure system that remains set to bring a stronger surge of moisture for rain during Sunday. Forcing for vertical motion is mainly tied to the southern stream shortwave initially which backs and strengthens the wind field below 700 mb. Moisture transport that was lacking closer to the surface today becomes strong enough to better saturate the low levels by Sunday afternoon, especially from the Ohio border through metro Detroit where likely/numerous POPs remain warranted. A trend to monitor is from longer projections of hi-res runs like the RAP and ARW which suggest light rain mostly misses SE MI. These solutions do not back the wind as much in the low to mid levels apparently due to earlier influence from the northern stream trough digging in from central Canada by afternoon. This weakens and deflects isentropic lift/moisture transport eastward before saturation in SE MI. The plan is to buy another forecast cycle and look for additional support of these hi-res runs from the remainder of the model suite. In the meantime, a higher POP/low QPF scenario is maintained with entry level likely POPs near the Ohio border tapering to chance toward the Tri Cities and northern Thumb through Sunday afternoon. All rain precipitation type is favored by a comfortable margin in QPF- producing solutions. The northern stream 500 mb trough takes over Sunday night beginning with the strong cold front that it whips through Lower MI during the evening. The frontal passage immediately transitions any remaining precip to snow, although with coverage being surprisingly low given the strength of cold advection over the Great Lakes. Model RH plan views and soundings show the dry slot around the south flank of the trough overwhelming any potential for significant lake effect snow showers this far SE during Sunday night. The primary impact becomes the surge of colder air driven in on initial wind NW gusts of 30 to 40 mph. The peak gusts diminish toward midnight while colder air continues to arrive with temperatures down into the 20s and wind chill into the teens by sunrise Monday. The low level thermal trough becomes entrenched for Monday and limits temperatures to a struggle for mid 30s across Lower MI, which feels more like mid 20s when factoring in 20 mph NW wind gusts for much of the day. Model boundary layer RH fields remain dry and a 300 wind direction less favorable for extension of lake effect snow showers this far east. Some flurries from higher based diurnal stratocu is about all the potential supported during the day and then just stratocu Monday night as the wind backs with the passage of high pressure through the Ohio valley. Ridge will slide through the area Tuesday and Wednesday keeping the weather fairly quiet with a slight warm up as winds turn back to the SW. There is a weak shortwave lifting NE ahead of the next trough which could drum up a few light showers Wednesday. Otherwise, next chances of showers will come later in the week Thursday and Friday as the next longwave trough passes east through the Great Lakes. MARINE... Moderate southwest flow will temporarily slacken the remainder of the day and through tonight as the pressure gradient briefly weakens across the central Great Lakes. Existing Small Craft Advisories along portions of the Lake Huron nearshore waters and outer Saginaw Bay will thus be allowed to expire. Southwest winds will then quickly ramp up again Sunday afternoon and especially Sunday night and into early Monday morning as low pressure developing over the upper Midwest rapidly deepens and tracks northeast towards the northern Great Lakes. This system will pull a strong cold front across the region flipping winds to the northwest along with a surge of cold air. Winds to gale force across the Lake Huron basin will be likely during this time, and Gale Warnings have been issued for all of the Lake Huron waters. The potential will exist for a few gusts to strong gales Sunday night across the northern Lake Huron waters. Small Craft Advisories will also be in effect during this time for Lake St. Clair and western Lake Erie, where it is anticipated that gusts will remain just below gale force. Moderate northwest flow remains in place through the middle of next week as high pressure slides eastward across the Ohio Valley. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. Lake Huron...Gale Warning from 7 PM this evening to 10 AM EST Monday for LHZ421- 422-441>443-462>464. Gale Warning from 4 PM this afternoon to 10 AM EST Monday for LHZ361>363. Lake St Clair...Small Craft Advisory from 7 PM this evening to 10 AM EST Monday for LCZ460. Michigan waters of Lake Erie...Small Craft Advisory from 7 PM this evening to 10 AM EST Monday for LEZ444. && $$ AVIATION.....DRK DISCUSSION...BT MARINE.......IRL You can obtain your latest National Weather Service forecasts online at
Area Forecast Discussion
National Weather Service Marquette MI
546 PM EST Sun Nov 21 2021 .SHORT TERM...(This evening through Monday) Issued at 324 PM EST SUN NOV 21 2021 Radar and satellite imagery, as well as local obs show a cold front passing through the UP this afternoon. As the cold front is moving through, obs and webcams show areas across the UP seeing light snowfall, with some bursts of heavy snowfall seen at times too. Therefore, expecting most of the area to maybe get a quick inch from this cold frontal passage, with some spots outside the NW wind lake- effect belts seeing up to 2 inches locally. The western NW wind lake- effect belts could see up to 4 inches, with locally an inch or two more in the higher elevations, this afternoon into tonight as lake- effect snow starts after the front passes (we are starting to see the lake-effect begin now from Ironwood to the Keweenaw). Given the strong post-frontal winds, could also see some patches of blowing snow too. In the eastern NW wind lake-effect belts, models are showing a good agreement whereby lake-effect snow behind the cold front develops this evening and continues on through tonight into Monday. This lake-effect snow is expected to drop a significant amount of snowfall in the snowbands; thinking there is going to be about 6 to 8 inches this evening into early Monday morning where the snowbands set up, with locally up to 10 inches possible at spots. Areas of blowing snow are also expected tonight into tomorrow, particularly along the Lake Superior shoreline as gusty winds up to 50 mph could greatly reduce visibilities. Therefore, a Winter Weather Advisory is in effect for Alger, Luce, and Northern Schoolcraft counties from 5pm this evening to 10am tomorrow. Snowfall rates should begin to ease up, and eventually end, from west to east Monday as a ridge begins to build in from the Northern Plains. Another hazard that is expected this afternoon into tonight is gusty winds. Winds up to around 45 to 50 mph are possible across Upper MI this afternoon into early tonight as the cold front brings a strong temp and pressure gradient across the UP. Behind the cold front, impressive vertical mixing up to around 5 kft is expected this afternoon. We could see this impressive mixing continue into tonight as well. Some obs at KCMX this afternoon have shown peak wind gusts up to 59 mph, so it does seem possible that winds will overachieve what is already forecasted (as well as the max of model guidance). However, I also have my doubts for having the Wind Advisories continue into the overnight hours as the latest HRRR and RAP model soundings do show some areas not supporting strong mixing of the winds early tonight. If this were to occur, then Wind Advisory level gusts would not be realized. However, I`m not fully convinced to cut short the Wind Advisories yet, as the NAM3km is still showing strong mixing, and the HRRR at other places is still showing strong mixing throughout the overnight hours. Therefore, keeping all but Gogebic County under a Wind Advisory until the overnight hours. (Did not include Alger, Northern Schoolcraft, and Luce Counties either, but that was because the high winds are included in the Winter Weather Advisory.) Another threat we could see this afternoon into Monday is lakeshore flooding, particularly in the east in Alger and Luce Counties. Due to the strong NW winds behind the cold front this afternoon and tonight, we could see some minor beach erosion and lakeshore flooding from the Porkies up to the tip of the Keweenaw as waves get up to 10 to 14 feet in height. However, over in Alger and Luce Counties, expect waves to reach up to 14 to 20 feet; therefore, a Lakeshore Flood Advisory has been issued for Alger and Luce Counties from 7pm tonight to 10am Monday morning, as some beach erosion and minor damage to docks and property is possible. The lakeshore flooding is expected to end Monday as the winds over Lake Superior begin to die-down. On Monday, expect the lake-effect snow and breezy conditions to end from west to east throughout the day as ridging builds into the area. However, given that cold air aloft is still expected to be above us, thinking the high temps will struggle to get above freezing Monday. .LONG TERM...(Monday night through Sunday) Issued at 415 PM EST SUN NOV 21 2021 Medium range models are in good agreement in showing a -NAO developing this week, but it may only be short-lived with indications of the NAO trending neutral by the start of Dec. During the long term part of the fcst, there will be one main shortwave trof of concern, and the -NAO will work to drive this shortwave to amplify se thru the Great Lakes into the ne U.S. late week. Just beyond this fcst period toward the middle of next week, another shortwave may be forced on a similar amplifying trajectory, but with the NAO trending neutral, it may not amplify as far to the se as its predecessor unless a transitory building western N America ridge becomes sufficiently amplified. As for pcpn, pcpn over the next 7 days may end up being exclusively lake effect driven. Developing LES this aftn/tonight will linger into Mon night over the e, and then we`ll await the next amplifying trof in the late Wed to Fri time frame. Similar to the system affecting the area today, this wave will likely have limited synoptic pcpn for Upper MI. Push of colder air on the backside will then bring another bout of nw flow LES, beginning Wed night, continuing thru Thanksgiving day and winding down on Fri. At this point, it looks like dry weather should mostly prevail over the weekend. As for temps, seasonably cool conditions early this week will trend warmer (above normal) by midweek ahead of the next amplifying trof. Temps will then trend down (blo normal) Thanksgiving Day thru Sat on the backside of the amplifying trof. Warming to above normal will then get underway again late weekend/early next week as the late week trof departs and the next potential amplifying trof approaches. Beginning Mon night, lingering light nw flow LES off eastern Lake Superior will continue to diminish and should end around sunrise as sfc high pres ridge passes across the area, shifting winds offshore. There may yet be a few flurries over the w in the evening. With winds becoming light and skies becoming clear to partly cloudy, expect a chilly night. Traditional interior cold spots across the w half may slip blo 10F, especially in areas where some snow cover exists. Otherwise, teens and 20s will be the rule, warmest east along Lake Superior. Mid-level ridging will then build eastward from the Northern Plains to the Upper Great Lakes by Tue evening and then to the Lower Great Lakes by Wed aftn. To the w, a trof moving across the Pacific NW Tue morning will move out across the Plains on Wed. As a result, pres gradient will tighten across the area Tue/Tue night btwn the departing sfc high pres ridge and the sfc trof moving out over the Northern Plains. This will translate to a 40-50kt low-level jet developing into the Upper Lakes later Tue into early Wed. Peak low- level jet speeds could reach 50-60kt Tue night. The resulting strong waa (850mb temps surge to 5-10C Tue night) will serve to strengthen inversion which will then work to inhibit increasing winds at the sfc, especially Tue night. While wind gusts will reach up to 25- 30mph Tue aftn, the increasing stability Tue night will keep winds in check. Possible exceptions will be near Lake MI and in the s to sw wind downslope areas near Lake Superior. Won`t know for sure until we get to Tue, but right now, GFS fcst soundings more so than NAM fcst soundings suggest potential of advy level wind gusts in those areas Tue night. Despite the strong waa/isentropic ascent, there is too much dry air across Upper MI for pcpn. Pcpn Tue would be more likely to occur to the n, deeper into the retreating cold air where moistening of the lower levels would be easier to achieve. With the surge of warmer air into the area Tue night, high temps on Wed should push solidly into the 40s F across the board. The mid-level trof moving across the Plains on Wed will amplify thru the Great Lakes on Thanksgiving Day and into the ne states on Fri. Associated cold front will move across the area Wed night, setting the stage for nw flow LES and blustery conditions (not nearly as windy as the current system over the area) to develop from w to e Wed night/Thanksgiving Day as 850mb temps tumble back to the -12 to -16C range. At this point, it doesn`t look like a major lake effect event, but advy amounts are probably a good bet, especially btwn Marquette and Newberry. If you have travel plans for the Thanksgiving holiday, continue to monitor the forcast in the coming days. LES will then diminish into Fri. There are some hints that a shortwave may drop se on the backside of the trof over the ne states over the weekend, so a dry weekend across the entire fcst area is not certain. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 545 PM EST SUN NOV 21 2021 Behind a cold front, MVFR conditions will continue as lake-effect sn sets up in the NW lake effect snow belts. Expect gusty NW winds across all TAF sites until around Mon afternoon. As the lake-effect sn begins to wind down in the west, could see improvement to VFR conditions at KIWD and KCMX late Mon. Given that KSAW is outside the typical NW lake-effect snow belts, it will stay VFR through the period. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 415 PM EST SUN NOV 21 2021 NW winds are gusting up to 40-45 kts across Lake Superior this afternoon, including a few storm force gusts up to 50-55 kts, as a cold front passes. Expect the winds to slowly diminish tonight and Monday, getting below gale force gusts by late Monday. Winds should decrease to 20 kts or less by Monday night. Expect the winds to increase quickly again from the south/southwest Tuesday, with gusts up to 30 kt Tuesday night. Gale gusts up to 35 to 40 kt are possible Tuesday night and Wednesday across the east half of Lake Superior. Winds are expected to decrease to around 25 kts for a short time Wednesday evening, before another cold front moves across the lake Wednesday night and Thanksgiving Day, bringing with it northwesterly winds up to 30 kts across the lake. Expect the winds to become north/northwesterly Thursday night, with winds to diminish to around 20 kts or less from west to east Thursday night into Friday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Wind Advisory until 11 PM EST this evening for MIZ001>003-084. Winter Weather Advisory until 10 AM EST Monday for MIZ006-007- 085. Lakeshore Flood Advisory until 11 AM EST Monday for MIZ006-007. Wind Advisory until midnight EST /11 PM CST/ tonight for MIZ004- 005-010-011. Wind Advisory until 1 AM EST /midnight CST/ Monday for MIZ012>014. Lake Superior... Gale Warning until 10 AM EST Monday for LSZ249>251-266-267. Gale Warning until 7 AM EST Monday for LSZ243>248-264-265. Gale Warning until 3 AM EST /2 AM CST/ Monday for LSZ162-240>242- 263. Lake Michigan... Gale Warning until 10 AM EST Monday for LMZ221-248-250. && $$ SHORT TERM...TAP LONG TERM...Rolfson AVIATION...07 MARINE...TAP/Rolfson
Area Forecast Discussion
National Weather Service Paducah KY
1104 PM CST Sat Nov 20 2021 .SHORT TERM...(Tonight through Sunday night) Issued at 128 PM CST Sat Nov 20 2021 Southerly surface winds and southwesterly low level flow will continue across the PAH forecast area through tonight. Meanwhile, with an approaching mid level shortwave, warm advection rain is possible after midnight in the northern half of the region, especially north of I-64. As the surface cold front approaches from the west, deeper moisture and dynamics will combine for development of widespread rain across most of the region, with the highest PoPs over easternmost MO, western KY, and southwestern IN during the day Sun as the front continues to move eastward. A clap of thunder or two is possible near the AR/TN line. Otherwise, the column appears too stable for tstms at this time. A half inch or less QPF is expected. Pcpn should be out of even the southern Pennyrile region of KY by Sun night as winds will be out of the northwest by then, gusting above 20 mph at times after midnight. After a mild night tonight in the lower half of the 40s, and highs in the 50s Sun, lows Sun night will be at or below freezing. .LONG TERM...(Tuesday through Saturday) Issued at 128 PM CST Sat Nov 20 2021 Strong high pressure will move across the area Monday through Tuesday, as a deep longwave forms over the east 1/3 of the nation. This airmass with the high will bring us our coldest and driest air of the season so far. Return flow is forecast to get underway Tuesday night on the backside of the high, and as a mid level ridge passes across the region. It will be warmer Wednesday but continued dry as we sit between a high over the Mid Atlantic and a surface cold front that should extend from the Great Lakes southward into the southern Plains. The front will continue east Wednesday night as a positive tilt longwave takes shape over the nation`s mid section. We expect rain will expand in coverage and move into the area especially after midnight. The signal is becoming more persistent for our peak rain chances to be on Thanksgiving day in conjunction with the front moving across the area. There is a growing consensus as well that the activity will end more quickly than what the models depicted over the past 2- 3 days, a trend that was recognized by the previous shift, and continues to be supported by the latest ensemble and deterministic output from the GFS/GEFS and EC/ECENS. There is still some wavering with timing, so adjustments will continue. The rapid end will likely mute or eliminate any concern for a brief change over to a light rain/light snow mix. Still way out there, but impacts are not anticipated at this time. Friday will be dry and colder, with dry weather continuing into the first half of the weekend. && .AVIATION... Issued at 1104 PM CST Sat Nov 20 2021 With the 06z Sunday WFO PAH TAF issuance, the trend for VFR to MVFR ceilings and visibilities will initially take place in the 12z-16z Sunday time frame across the TAF sites. A trend from MVFR to IFR during the 14z to 20z Sunday for KPAH, KEVV, and KOWB just ahead of the cold frontal passage. Behind the frontal passage, a return from MVFR to VFR ceiling and visibility conditions should occur within two to five hours. The current HRRR simulated reflectivity forecast seems to do well on the timing and impact of rain on the WFO PAH TAF sites, depicting the warm conveyor belt and isentropically lift zone for precipitation overnight and through the day on Sunday. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ SHORT TERM...DB LONG TERM...08 AVIATION...Smith
National Weather Service Raleigh NC
1000 PM EST Sun Nov 21 2021 .SYNOPSIS... High pressure will move offshore tonight as an upper level disturbance approaches the region from the west. A cold front will move across the area on Monday, bringing a chance of rain to the area along with much cooler temperatures and breezy conditions. Well below normal temperatures will remain in place across the area through the middle of the week, then moderate closer to normal by Thursday. && .NEAR TERM /TONIGHT/... As of 1000 PM Sunday... A surface cold front has made its way to the spine of the Appalachian Mountains. High overcast skies cover North Carolina, while low to mid clouds extend across the western half of the state. Despite some dry air that is present, this still appears to be a high pop/low QPF scenario. Increased pops to categorical overnight primarily northwest of US-1 as synoptic and high-resolution models have good run-to-run consistency in showing showers in all locations. The latest runs of the HRRR have continued to slow down the arrival of the precipitation, and this trend has been blended into the forecast. This keeps the Triad dry through at least midnight, and still have the bulk of the rainfall waiting until just before sunrise to reach the Triangle. Cloud cover will keep temperatures warmer than they have been, in the mid to upper 40s. && .SHORT TERM /MONDAY AND MONDAY NIGHT/... As of 1000 PM Sunday... The one tweak to Monday`s forecast this evening is that showers will be slightly delayed in clearing the region. Rain should end in the Triad around noon, across the Triangle in the early afternoon, and across the Coastal Plain by mid/late afternoon. The previous Sunday 2:13pm discussion follows. The surface cold front and associated band of showers will make rapid progress through the area on Monday. An additional few hundredths of an inch of rain are possible area-wide as the front moves through, for a grand total of a tenth to a quarter of an inch by the time all is said and done. Again, given abundant dry air ahead of this system, not to mention that the best forcing will be located across the Great Lakes vs central NC, this will not be a significant rain event. Rain will end in the Triad by mid morning, across the Triangle around noon, and across the Coastal Plain by mid afternoon. Despite the lack of noteworthy rainfall, the front will usher in colder temperatures and breezy conditions. Some degree of cold advection should begin by late morning in the west and as skies clear out and low level lapse rates steepen, breezy winds in the 15- 20mph range can be expected. From the Triangle eastward, clearing skies and breezy winds will likely hold off until after noon. At least some degree of breeziness will continue into the evening hours coincident with the arrival of much colder air aloft and lower thicknesses as the base of the upper trough moves through the area. Temperatures tomorrow will remain somewhat mild, but slightly cooler than today`s highs. Given the delay in arrival of much cooler air until later in the afternoon/early evening, highs should still manage to reach the mid/upper 50s. However once the cooler air settles in tomorrow night, look for overnight lows to drop into the upper 20s/around 30 area-wide. && .LONG TERM /TUESDAY THROUGH SUNDAY/... As of 400 PM Sunday... As the mid/upper trough moves offshore and cool ~1030 mb Canadian surface high pressure slowly moves across the TN Valley and Appalachians on Tuesday, height rises and subsidence will result in sunny skies over central NC. However, continued NW flow and strong CAA will result in highs only reaching the mid-to-upper-40s, which is 10-15 degrees below normal. As the high slightly strengthens and moves overhead on Wednesday morning, clear skies and light winds will result in ideal radiational cooling conditions. Lows will only be in the lower-to-mid-20s, and a few upper teens in the usual coldest spots can`t be entirely ruled out. These will be the coldest temperatures our region as seen since the spring. Shortwave ridging will move across the area on Wednesday and Thursday as surface high pressure weakens and pushes south. As the flow turns southerly, warmer temperatures on Wednesday (highs in the lower-to-mid-50s) and Wednesday night (lows in the upper-20s to lower-30s) will give way to even warmer temperatures on Thursday when highs will reach the lower-60s. The GFS and ECMWF continue to be in good agreement that a shortwave trough and cold front will then move across central NC Thursday night into Friday morning. Both the 12z ECMWF and 12z GFS now have precipitation with it, as the GFS has trended toward the sharper trough solution seen on the ECMWF. More than a third of GEFS have some precipitation, as do the majority of ECMWF ensembles. Forcing looks decent with the shortwave, and the GFS has PW values up to and even exceeding an inch. Thus bumped POPs a bit above NBM once more, to low chance across the area on Thursday night in the west and Friday morning in the east. Dry weather and below-normal temperatures will move back in behind the front for the rest of Friday into Saturday, before the high may move offshore and temperatures warm a bit on Sunday. Another shortwave trough looks to move across the area on Sunday, but the air will be much drier and confidence is too low for even slight chance POPs at this time. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... As of 700 PM Sunday... 24 hour TAF period: VFR conditions will begin the TAF period, but MVFR ceilings are expected at all TAF sites tonight with IFR possible at KFAY and KRWI as a cold front moves through central NC tonight into Monday morning. Skies will clear behind the front rather quickly and allow for VFR conditions to return, but gusty winds will follow out of the NW with highest gusts expected at GSO/INT. A strong pressure gradient at the surface will allow the gusty winds to persist into the overnight hours, likely not subsiding until sometime Tuesday morning. Outlook: High pressure will settle in over the southeast Tuesday through Thursday maintaining VFR conditions across the area. The next chance for sub-VFR conditions looks to be Friday morning as another cold front is forecast to push through central NC. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Leins NEAR TERM...Green SHORT TERM...Green/Leins LONG TERM...Danco AVIATION...Swiggett/Luchetti