Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/20/21

Area Forecast Discussion...UPDATED
National Weather Service Amarillo TX
543 PM CST Tue Jan 19 2021 .AVIATION... For the 00Z TAFs, a surface trof of low pressure will deepen over eastern CO and eastern NM on Wednesday. The associated pressure gradient will result in gusty southwest winds at the terminal sites from around 16Z Wednesday through the afternoon hours. Periods of mid and high level clouds are also expected during this forecast cycle. 02 && .PREV DISCUSSION... /Issued 254 PM CST Tue Jan 19 2021/ SHORT TERM...Tonight through Tomorrow Night... Dry air is filtering in through the day today with the light snow and flurries coming to an end across the northwest. Clouds are beginning to clear across the Panhandles with scattered clouds possible through the rest of the day. Temperatures are struggling to warm into the lower 40s across most of the Panhandles with the cloud cover that persisted most of the morning. With skies clearing, the temperatures may be able to rise into the lower to mid 40s across most of the area. RAP 500mb analysis shows a closed upper level low pressure system meandering towards the Pacific off the coast of southern Cali where it will remain stationary through tomorrow night. Meanwhile, a shortwave trough will move across central Canada with an 850mb closed low swiping just north of the Great Lakes. West southwesterly winds aloft with surface winds out of the southwest ahead of the surface trough extending from the closed low. With southwest surface winds, temperatures will recover nicely and warm into the upper 50s to lower 60s. A 35 to 45 knot 850mb jet will just clip the northeast Panhandles with some daytime mixing, winds will may gust as high as 40 knots at the surface. Rutt FIRE WEATHER... Elevated fire weather conditions are possible tomorrow in the northeast Panhandles. Southwest sustained winds of 15 to 25 mph are possible with gusts up to 30 to 35 mph. Minimum relative humidity values will be above 25 percent across the Texas and Oklahoma Panhandles. ERC percentiles are the highest in the northeast in the 50th-69th percentile, along with a few spotty areas int he 70th-89th percentile. The fire weather conditions are driven mainly by the wind speeds. Rutt LONG TERM...Thursday Through Monday Night... Cutoff low over the Baja area will become more of an open wave trof and push southwest flow over the Panhandles with warmer temperatures in the upper 50s to lower 60s across the Panhandles. Some models hint at a little moisture out of the southeast, so have a slight chance of rain showers in the southeast Thursday night. Cold front right now looks to stall out around the northern Panhandles and then push through in the evening on Thursday, with east northeast winds and low clouds likely advecting over the Panhandles. Not much will change on Friday as the cooler air will remain over the Panhandles under a more zonal flow aloft and thus the highs will only be in the 40s. Another system over the Pacific northwest will be barreling down the west cost on Friday into Saturday, and will return moisture to the southern Rockies as an open wave trof Friday night through Sunday. Most of this moisture will be taken up over the Rockies and it looks like very little if any will be over the Panhandles. On the plus side, dry/mild southwest flow will likely bring temperatures back in the 60s over the weekend, but breezy southwest winds 15-25 mph will assist in providing these temperatures. Monday is still a little uncertain, as we might see just enough moisture clip the southeast to get some rain maybe even a thunderstorm, as well as possible light snow. A fast moving cold front may overtake the area before the rain can clear out and provide a brief period of snow. Confidence is very low in what will happen on Sunday as there`s quite the model difference. Weber && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && $$
Area Forecast Discussion
National Weather Service Denver/Boulder CO
804 PM MST Tue Jan 19 2021 .UPDATE... Issued at 802 PM MST Tue Jan 19 2021 Looking at the latest data, appears best threat for strong winds will be Wed morning thru Wed aftn. Cross-sections show best mtn wave, in the 15z-21Z window, so strongest wind gusts may end up in that time period. Thus timing of high wind warning could be somewhat early but will leave it as is to avoid confusion. Otherwise only minor adjustments to current forecast overnight. && .SHORT TERM...(This evening through Wednesday) Issued at 218 PM MST Tue Jan 19 2021 The ECMWF and GFS agree that the upper low to our west will cutoff and move off the coast of California and Mexico tonight. Continued warming aloft due to warm southwesterly advection around the low will continue to increase mid level stability tonight. The temperature profile is beginning to seem more favorable for mountain wave amplification, and models are trending up on forecast winds and gusts speeds in the Front Range mountains and foothills tonight and tomorrow. The HRRR is now showing peak gusts in the Front Range mountains up to around 75 mph in some areas. QG fields also show moderate mid level synoptic scale subsidence up to about 10 mb/hr in the 600 to 500 mb layer above the ridge line. Cross sections over and across the Front Range show a decent stable layer with up to 60 kts of flow perpendicular to the mountains on Wednesday morning and model soundings show a strong inversion developing between around 750 and 700 mb in the foothills. These conditions seem sufficient for marginal warning criteria and are trending up, so we have issued a High Wind Warning for the Front Range foothills from just after midnight tonight through late Wednesday afternoon, for possible winds of 35 to 45 mph gusts up to 75 mph. The strongest winds are expected between 5 AM and noon tomorrow. Lows on the eastern plains will be in the high teens and low 20s F tonight, while lows in much of the foothills and nearby plains will be a few degrees warmer due to downslope warming of mountain wave winds. Both models predict that the cutoff low will remain off the coast to our southwest through the day Wednesday and into the night. Wednesday will be much warmer than today, with highs expected in the mid to upper 50s F on the plains and mid 30s in the mountains. It still looks to be dry through Wednesday. Some flurries in the northern mountains are possible Wednesday, but no significant accumulation is expected. .LONG TERM...(Wednesday night through Tuesday) Issued at 218 PM MST Tue Jan 19 2021 Winds will be decreasing through the evening and overnight hours as the mountain wave dissipates. Still should be pretty breezy for the Foothills overnight, with some gusts up to 50 mph possible, especially during the first half of the night. Windy conditions will also keep temperatures mild overnight, only dropping to the upper 20s/low 30s near the foothills. West of the Divide, shallow moisture and westerly winds could allow for continued cloud cover and perhaps a flurry or two. Zonal flow establishes on Thursday with the a jet streak to our north and south. Cross-sections show a little more moisture aloft and very weak synoptic scale lift during the day, which should be enough for some scattered cloud cover through the day. Over the mountains, the low-level moisture depth increases a bit through the day, so it wouldn`t be surprising to see some more scattered snow showers, with very light accumulations. On the plains, not much to write home about. With increased cloud cover and mid-level temperatures a couple degrees cooler than Wednesday, highs should be about 5F lower than Wednesday`s. Weather pattern turns more active Friday into this weekend. Influx of Pacific moisture should spread across the state during the day Friday ahead of an upper level trough. Winds aloft turn more southwesterly, under a broad overrunning/warm air advection regime. QG ascent is pretty weak through the day, but there should be increasing coverage of snow showers on the western side of the Divide. The trough is expected to cutoff over Nevada Friday night into Saturday, with continued southwesterly flow and moisture advection. Synoptic scale lift increases a bit through Saturday, and widespread light snow is expected for the mountains, favoring southwest facing slopes. The trough weakens a bit by Sunday and transitions back to an open wave as it drifts east/southeast. Cross-sections still show plenty of moisture up to about 400mb, and orographic snows will likely continue through the day, even as synoptic scale lift ends up south of the area. System should be basically clear of the area by the end of the weekend. The start of the next week looks fairly active as well with another one or two troughs potentially impacting the area. For the mountains... a long-duration snowfall is looking more likely, especially for mountains west of our forecast area. Too early to speculate on any storm totals here, but at the very least there`s moisture to track in the medium range. Over the plains, it`s unlikely any of the moisture reaches the ground as there`s no real forcing mechanism to help us out. "Best" chance for any measurable precip over the plains comes sometime Saturday night or Sunday. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 802 PM MST Tue Jan 19 2021 VFR overnight. Winds have become light and variable at DIA but should trend to more SSW by 06z. && .BOU WATCHES/WARNINGS/ADVISORIES... High Wind Warning from 2 AM to 5 PM MST Wednesday for COZ035-036. && $$ UPDATE...RPK SHORT TERM...Direnzo LONG TERM...Hiris AVIATION...RPK
Area Forecast Discussion
National Weather Service Goodland KS
845 PM MST Tue Jan 19 2021 .SHORT TERM...(This evening through Wednesday night) Issued at 119 PM MST Tue Jan 19 2021 Satellite imagery and 500mb RAP analysis showed northwesterly flow over the region early this afternoon. The main features observed in the pattern included a large closed low off of the southern California coast with weak ridging out ahead across the Four Corners region. As this low continued to push southward, split flow prevailed across the central Rockies. At 1:00 PM MST, north to northwest winds were between 15 and 20 mph, with gusts around 30 mph for portions of the area. Mid to high level clouds had exited the region ahead of the west coast system as temperatures ranged in the mid 30s to mid 40s. Tonight, temperatures fall into the upper teens to low 20s as a surface trough approaches the region and light winds turn to the southwest. Dry weather continues with the flow aloft becoming a bit more zonal and the ridging ahead of the upper low broadening across the southern CONUS. Wednesday looks to be a pretty pleasant day overall. Warmer air filters into the area, with highs forecast in the upper 50s to low 60s. A surface trough extending southward from a low in central Canada pushes across the High Plains, with winds shifting from southwest to northwest through the day. With little moisture in place, dry conditions and sunny skies prevail. Relative humidity values fall as low as the upper teens to low 20s across a good portion of the region in the afternoon. Winds look to stay relatively light, around 15 mph, mitigating fire weather concerns at this time. Wednesday night, the low off of the California coast begins its journey onshore, weakening in the process. A weak cold front associated with the Canadian system traverses the area in the evening. No precipitation is expected as temperatures fall into the upper teens to mid 20s. .LONG TERM...(Thursday through Monday) Issued at 247 PM MST Tue Jan 19 2021 At the beginning of the long term period, forecast guidance shows a westerly zonal flow over the CWA as the northern and southern jetstreams merge together over the area with a weak trough residing over southern CA. This trough is absorbed into the joined jetstream and the westerly flow aloft continues through Friday with another trough developing over the Pacific coast behind a weak ridge during Friday evening. On Saturday, the flow aloft begins to turn southwesterly as the trough out west tilts positively causing the CWA to be between the trough in the west and the ridge in the east. This upper air pattern continues going into Sunday at which the trough starts to move eastward. The GFS continues to show a quicker eastward progression for the trough compared to the ECMWF as in previous model runs. On Monday, a jet streak digs in along the Pacific coast behind a shortwave in the jetstream and places the CWA underneath the front end of the trough as it redevelops in the west. Models show uncertainty this far out with the timing on the redevelopment of the trough, so this situation will be monitored as it looks to set up a potential system to start out next week. At the surface, some precipitation may be expected for a portion of the Tri-State area over the weekend. Friday may see some breezy conditions as a surface high sets up near MN/IA/SD with another low over CO. The CO surface low may travel near the Tri-State area Saturday night into Sunday. As moisture is wrapped around this system, areas east of a line from Benkelman, NE to Hoxie, KS as well as the northern part of Yuma county may see a slight chance of light snow on Sunday morning. Models show a cold air mass possibly passing into the Tri-State area around the same time. Minimal amounts of precipitation is expected if it occurs during this time. The Tri-State area expects high temperatures on Thursday in the upper 40s to middle 50s followed by Friday seeing highs in the lower to middle 40s. Saturday`s highs range from the middle 40s in the northern portions of the Tri-State area to the middle 50s in the southern portions. Tri-State area highs on Sunday expect to be in the upper 30s to middle 40s range with highs in the lower to middle 50s on Monday. Tri-State area overnight lows for Thursday expect to range between the upper teens to the lower 20s followed by Friday`s overnight lows ranging between the lower to upper 20s. The Tri-State area expects to see overnight lows in the upper teens in the western portions to the upper 20s in the eastern portions. Overnight lows in the upper teens to lower 20s can be expected for the remainder of the forecast period. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 845 PM MST Tue Jan 19 2021 VFR conditions are expected at KGLD and KMCK through the period. Southwest winds up to 10kts at taf issuance will increase toward 15kts or so at KGLD by 09z and continue sunrise. For the daytime hours winds steadily veer to the west around 17z at speeds near 10kts. From 18z-21z northwest winds of 12 to 15kts with higher gusts are expected. After 22z winds subside and become light and variable through 06z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JBH LONG TERM...076 AVIATION...99
Area Forecast Discussion
National Weather Service Blacksburg VA
1025 PM EST Tue Jan 19 2021 .SYNOPSIS... A disturbance tonight brings yet another round of upslope showers for the Western Slopes. Following the disturbance, strong westerly winds bring gusty conditions to the area Wednesday morning. Another weak disturbance brings precipitation chances generally for areas in far southern southwest Virginia and western North Carolina. Following this disturbance, drier conditions persist into the weekend. && .NEAR TERM /THROUGH WEDNESDAY/... As of 1020 PM EST Tuesday... No changes to Wind Advisory or Winter Weather Advisory. Have slowed down the arrival of upslope snow showers in the west. HREF and HRRR guidance have the precipitation reaching southeast West Virginia around 8-9Z/3-4AM. Tonight, another disturbance is expected to move through the area, sparking more upslope showers and bringing additional snowfall accumulation primarily for Western Greenbrier Co. Amounts should generally top off around 3 inches. Following behind this disturbance, the LLJ is expected to crank up with speeds 40-60kts aloft. Greatest mixing for the winds will be along the southern Blue Ridge down into the NC Mountains. It is signaled that there could be a few isolated gusts within advisory criteria north of Roanoke along the Blue Ridge, but they will be too isolated to warrant issuing for at the moment. Upslope showers start to wrap up tomorrow and transitions to a rain snow mix besides for the highest elevations as good CAA continues, along with gusty conditions. Generally, winds should start to subside after noon tomorrow. The CAA should keep highs down tomorrow. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... As of 200 PM EST Tuesday... Weak system skirts by to our south Thursday before a fair weather Friday. Decreasing winds as we enter a fairly zonal flow pattern through the period. The latter half of the workweek will start with a quick weak mid level wave skirting by just to our south Thursday morning into Thursday afternoon. This wave may bring just enough lift and moisture to the North Carolina mountains/foothills and Grayson Highlands to touch off a little rain/snow. Any accumulations from snow and ice look to be minor with the highest amounts along the ridgetops. Elsewhere we are just looking at an increase in cloud coverage with dry air from a blocking high over eastern Canada choking the northern edge of the passing wave to our south. The weak wave of energy quickly passes south and east by Thursday evening into Thursday night as high pressure starts to push in from the northern Plains. Before the high gets here another weak wave of low pressure will pass to our south across the Gulf Coast states leaving us dry while ushering in additional clouds through the day Friday. As for temperatures, we look to see a bit in the way of moderation. Highs will return to the upper 30s and low to mid 40s in the west with upper 40s to low 50s in the east. Overnight lows will remain chilly in the 20s and 30s with our coldest air arriving Friday night as the high pulls in. Confidence remains moderate to high in the short term period. && .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 200 PM EST Tuesday... A dry and cold weekend gives way to a potential wintry mixed bag early next week. Overall not much change in the in the upper level flow which will continue to allow cold air to flood in while keeping the storm track suppressed just to our south. We will continue to watch this pattern through the weekend though as several pieces of energy work across the country heading into early next week. The big question that is yet to be solved by the models is in regards to the placement of the southern jetstream and an area of low pressure that will eject of southwestern United States Monday into Tuesday. The GFS and EURO continue to show varying solutions in timing and placement of these features. The GFS remains warmer and wetter while the Euro remains colder with a mixed bag. For now trended with a blend of the two along with central guidance which would keep chance Pops in play for both Monday into Tuesday. Opted for a bit of a bias toward a colder solution in the sense that we would see some overrunning as a residual cold air wedge will be left in place thanks Canadian high pressure/weak ridging drifting east from the weekend. This is illustrated very well from both the synoptic/ensemble point of view at least for the start of the event Monday with temps in the 20s and 30s as the southern stream system tracks north from the Mid- South. As a result a brief period of snow, sleet, and freezing rain looks likely Monday morning before a change to rain in the afternoon and evening as warmer air floods in. The question though that remains as mentioned above is how far that warm air makes it to overcomes the wedge in the late afternoon and evening. The other issue is the placement of low with the GFS trending further west leaving us in the warm sector compared to the EUro which sends the low overtop of a wedge that is yet to erode Monday into Tuesday. As it stands now, look for early next week as our next wintry weather event. Temperatures will be at or slightly below average over the weekend with highs in the 30s and 40s and overnight lows in the teens and 20s. Confidence remains moderate in the long term period. && .AVIATION /04Z WEDNESDAY THROUGH SUNDAY/... As of 640 PM EST Tuesday... VFR and light/variable winds at all TAF sites this evening. Another disturbance arrives late tonight, dropping ceilings back down and re-introducing upslope snow showers and mountain flurries into Wednesday morning. Stations east of the Blue Ridge will continue with VFR ceilings. Gusty conditions expected Wednesday with the strongest winds along the Blue Ridge. Extended Aviation Discussion... Thursday-Saturday favor mainly VFR. A storm system is expected to move from the southern Plains across the Deep South during this time. Models have trended drier for the Mid-Atlantic keeping the storm system south of the local region. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...Wind Advisory until 1 PM EST Wednesday for VAZ015>017-022-033. NC...Wind Advisory until 1 PM EST Wednesday for NCZ001-002-018. WV...Winter Weather Advisory until 1 PM EST Wednesday for WVZ508. && $$ SYNOPSIS...RR NEAR TERM...AMS/RCS/RR SHORT TERM...ET LONG TERM...ET AVIATION...RCS/RR
Area Forecast Discussion
National Weather Service San Angelo TX
551 PM CST Tue Jan 19 2021 ...New AVIATION... .SHORT TERM... (This evening through Wednesday) Issued at 252 PM CST Tue Jan 19 2021 It has been a cloudy and raw day across West Central Texas. As of the 2 PM hour temperatures range from the mid 40s to near 50 degrees across the area. Weak isentropic ascent has resulted in pockets of light rain and drizzle this morning and afternoon...although measurable rainfall amounts have been confined to the northwest Hill Country and Heartland. Meanwhile, afternoon satellite imagery shows an upper level cutoff low off the southern California coast, with a plume of Pacific moisture streaming eastward across northern Mexico and west Texas. Models indicate a shortwave trough embedded in the southwest flow aloft approaching the area tonight. The increase in large scale lift combined with an increase in moisture (PW values greater than 1 inch per forecast model soundings) will lead to precipitation developing overnight. High res models including the HRRR and NAMNEST show widespread rain developing after midnight across the Trans Pecos and northern Edwards Plateau and spreading northward into the area...with showers then lingering into the afternoon hours. Thus will continue to carry likely PoPs for much of the area tonight and tomorrow. The highest rainfall amounts are expected south of the I-10 corridor, with QPF amounts of around half an inch to an inch likely across the southeastern half of the CWA. Otherwise, temperatures will hold in the 40s and lower 50s tomorrow due to the abundant cloud cover and expected rains. && .LONG TERM... (Wednesday night through next Tuesday) Issued at 252 PM CST Tue Jan 19 2021 We are expecting somewhat of a relative lull in precipitation Wednesday night into Thursday morning. That`s not to say there won`t be any precipitation at all, but if there is it`s expected to be isolated and very light in nature. As we move through Thursday night into Friday morning, the closed low to the west is still expected to open up into a wave and generally weaken, but still provide at least a slight chance for precipitation across most of the area as shortwave energy and lift move across the southern plains. Warmer temperatures in the 60s will move back in on Thursday, followed by a weak cold front Friday, temporarily cooling temperatures into the mid 50s to lower 60s. Expecting mainly dry conditions Friday into Saturday morning as well. For Saturday, the next upper level system will be moving southeast toward southern Arizona, turning our low level winds back around to the south, and warming temperatures back into the 60s. Precipitation chances will again be in the forecast from Saturday afternoon into early next week. However, precipitation is expected to be fairly light and scattered at best Saturday into Sunday, with the best chance for significant precipitation Sunday night into Monday morning. There is relatively low confidence in these rain chances, and their timing at this time though, so the forecast should be monitored as we move closer to the weekend. Temperatures will be warm through early next week. && .AVIATION... (00Z TAFS) Issued at 542 PM CST Tue Jan 19 2021 Expect widespread MVFR to low end VFR ceilings this evening. The ceilings will lower to IFR by 08-09Z at the KSOA/KJCT sites and then the remainder of the terminals by 16Z. Patchy fog will reduce vsbys to 2-5SM on Wednesday. Also, light to moderate rain will move across West Central Texas late tonight through early Wednesday afternoon. Expect gusty northeast winds to 20 knots this evening. && .PRELIMINARY POINT TEMPS/POPS... Abilene 38 46 43 65 / 50 70 5 20 San Angelo 38 48 42 65 / 80 80 10 20 Junction 40 50 43 67 / 80 90 20 20 Brownwood 40 48 42 65 / 50 70 5 30 Sweetwater 37 46 45 63 / 40 70 10 20 Ozona 38 47 42 61 / 80 80 20 20 && .SJT WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...42 LONG TERM....20 AVIATION...21