Aikyam-Lab/Synoptic-Bench huggingface dataset:
1048 PM MST Sat Nov 21 2020 Quiet weather pattern expected through Monday morning with cool northwest flow aloft transitioning to southwest flow on Monday ahead of the next Pacific upper level trough. Mild day expected on Monday ahead of the Pacific upper level trough. Models show this trough digging south into the four corners region during the day with west to southwest flow at the surface and aloft across southeast Wyoming. The trough and associated cold front slow down a bit as the trough axis moves across the mountains. As of right now, the mountains have the best chance to see light snow accumulations with some snow showers possible for the lower elevations.
The low stratus layer will be in the process of being scoured out of the area early Sunday morning. Despite increasing clouds, lows Sunday night into Monday morning should be in the 30s however there is quite a bit of model spatial variability with temps between the low 30s and near 40.
High pressure will weaken today ahead of the next cold front. An upper level trough situated across the central U. An associated cold front will move into the region tonight.
Scattered showers are expected to move back inland and pivot northwestward overnight ahead of a coastal trough. Weak upper troughing will move into the area today, and an isolated thunderstorm cannot be ruled out, mainly south of KGNV. Onshore flow and coastal trough continues to produce enough low level convergence along the NE FL coastal areas for scattered showers at times that will push inland through the St Johns River Basin and US 301 Corridor before fading as they reach inland NE FL. Low level ridging over the Great Lakes will weaken as it slides eastward, allowing enhanced onshore winds across the region to weaken by Sunday. Behind it, a weak cold front will push into the Southeast. The front plus convergence from the inverted coastal trough will allow for continued chances for light coastal showers Sunday.
As main upper trough moves into the Southern Plains overnight, plan to see an uptick in convective development as lapse rates increase near and south of I-40. (This evening through Sunday) The slow-moving cold front will clear the Red River late this eveing.
Cold front has moved into southeast Oklahoma/northwest Arkansas late this evening. IFR/LIFR conditions still expected north of cold front overnight as boundary pushes slowly south. Mid level wave will continue to push through the region overnight, and will give the areal coverage of rain and thunder, along with the cold front a push southeast late tonight and into Sunday morning.
VFR persist for the first half of the TAF, ahead of a cold front and rain chances, 12z-15z Sun.
Sunday night-Monday night: Expect increasing upper level cloud cover Sun night as flow aloft backs to the WSW in advance of the amplifying longwave trough over the Great Basin, with strengthening southerly flow /low-level warm advection/ during the day on Monday -- on the eastern periphery of a developing lee cyclone in CO. precipitation chances and temperatures/winds will highly depend on the evolution of the aforementioned lee cyclone.
Fog may also form in the lower Treasure Valley and in the Weiser River Basin near Midvale and Cambridge. Sunny Sunday and continued cool in the valleys but milder in the mountains as an upper ridge passes through. Next Pacific upper trough will bring a chance of snow showers to eastern Oregon Sunday night, and western Idaho Monday, mainly in the mountains. Gradual clearing Monday night as the trough exits east.
Lows tonight in the low to mid 30s. High pressure follows in wake of short term sys Mon ahead of potent srn Rockies sw ejecting out through the plains late Tue and OH valley Wed. Strong low level warm advection ahead of this sys may yield some light rain Tue morning within leading warm advection wing however bulk of rain will hold off until Tue night in association with broad/moist warm conveyor belt ahead of occluding sfc cyclone and persist through Wed as sys is slow to lift out. Expansion of precipitation shield anticipated later this morning as surface cyclone ejects from south central Missouri into the Lower Ohio Valley by 12 UTC. Slight ceiling improvement out of IFR range with back edge of precipitation as cyclone continues northeast track into central Ohio by late afternoon.
High pressure will build across the region through Sunday ahead of the next trough arriving Monday afternoon.
The period begins with an upper level low pressure trough over the southwest U.
These clouds are helping keep temperatures several degrees warmer than this time 24 hours ago, and will likely translate to similar differences through sunrise. No impacts are expected with this aside increasing high clouds and slightly cooler afternoon temperatures for Sunday. On Sunday night/Monday, upper level trough digs along the British Columbia coast and into the Pacific Northwest.
250 AM MST Sun Nov 22 2020 Current surface analysis shows trough over the eastern Dakotas. Upper level analysis shows trough moving east of the region, with mostly clear skies. Ridging to the west of the region will move east over the area later today and tonight.
334 AM CST Sun Nov 22 2020 A broad area of rain and snow associated with weak PV advection with the upper trough will continue shifting across eastern MN and western WI this morning. Temperatures today and tomorrow will top out in the lower 30s to 40s, which is near to slightly above normal.
Upper trough currently moving through our eastern counties will be off into the Great Lakes later today. After the system departs, weak high pressure builds in behind it. Northwest winds today will be a bit breezy on the backside of the low but will become light and variable pretty quickly tonight. Winds will shift around to the southeast and become quite breezy on Monday as low pressure develops to our west.
849 AM EST Sun Nov 22 2020 Rain should continue to taper off this morning, but increase again this afternoon and evening with crossing low pressure.
The CDFNT wl cont to work SEWD acrs the rest of the area today into early tngt, as an assocd upr lvl trof shifts EWD acrs the region.
415 AM MST Sun Nov 22 2020 Current surface analysis shows trough over the eastern Dakotas. Upper level analysis shows trough moving east of the region, with mostly clear skies. Ridging to the west of the region will move east over the area later today and tonight.
Cooler, yet seasonable, temperatures are expected for Sunday, followed by slightly warmer conditions for the beginning of the work week.
High temperatures are expected to climb into the lower 50s. Have side towards cooler guidance and drier dew point values (GFS) through the overnight hours. On Monday, return flow will increase ahead of an area of low pressure moving towards the Central Plains.
The low will continue moving northeastward across the Ohio valley today while the associated cold front moves across the forecast area. Cooler and drier conditions are expected tonight into Monday as high pressure builds into the area.
After 06z, a low stratus deck should develop in the wake of a passing cold front as low level moisture gets trapped beneath a temperature inversion around 925mb.
A lee side trough of low pressure in Montana will move east tonight. With a frontal boundary across southwest North Dakota and cool high pressure to the north and east, there should be a northeast to southwest temperature gradient today. Highs should be in the mid 20s north central and in the lower 40s southwest.
BKN VFR CIGS begin to develop going into the early overnight hours as a cold front approaches from the north. /issued 355 AM CST Sun Nov 22 2020/ Early morning sfc analysis shows high pressure hanging on across the region while our approaching weak cold front is noted to our north, extending from low pressure the Ozarks and extending wswwd through the Red River Valley to the TX Panhandle. Water vapor imagery a trof digging through the cntl CONUS while the area remains in a generally zonal flow aloft.
The progressive upper trough responsible for clouds and perhaps a few light rain showers yesterday will be east of the Missouri River by midday. Right behind it is a somewhat broad, quick- moving ridge with its axis lining up with the Front Range around 00z. At the surface, Nebraska lies underneath an expansive high pressure spanning the entire Great Plains and Lower Mississippi Valley. Cloud cover and gusty winds should keep min temps from falling off too much, so trended toward the warmer guidance in the mid/upper 20s. Persistent southerly flow and an H85 thermal ridge ahead of the main storm system help push highs back into the 50s across the forecast area.
Seasonably cooler and drier air will filter in behind the front overnight, with the front reaching the Hattiesburg area by around daybreak Monday.
446 AM EST Sun Nov 22 2020 Latest satellite imagery early this morning shows mid and high clouds increasing across the area in advance of a fairly weak area of low pressure approaching the Ohio Valley.
Then expecting to see a cold front from the northern low push through later this evening bringing a west-northwesterly wind shift.
355 AM CST Sun Nov 22 2020 Early morning sfc analysis shows high pressure hanging on across the region while our approaching weak cold front is noted to our north, extending from low pressure the Ozarks and extending wswwd through the Red River Valley to the TX Panhandle. Water vapor imagery a trof digging through the cntl CONUS while the area remains in a generally zonal flow aloft.
An upper trough will move across the area from the northwest on Monday, followed by a stronger one on Thanksgiving Day. This will lead to cooler conditions along with gusty winds over the mountains and parts of the deserts.
Along with the wind, it will be several degrees cooler.
A cold front will move southward across the region this afternoon through tonight, bringing a wind shift from southerly to northwesterly along it. Seasonably cooler and drier air will filter in behind the front overnight, with the front reaching the Hattiesburg area by around daybreak Monday.
A healthy slug of moderate rain is occurring north and west of the low and will transition eastward through the region over the next several hours. As the low transitions up the Ohio Valley, the cold front will push through the region and rain will quickly taper off from west to east early to mid morning. This will result in a crisp overnight with temperatures bottoming out in the low to mid 30s. Despite a good amount of sunshine, highs will only reach the lower half of the 50s on Monday.
Looks like the low level cool advection is playing a role in cloud formation today. A lee side trough of low pressure in Montana will move east tonight. With a frontal boundary across southwest North Dakota and cool high pressure to the north and east, there should be a northeast to southwest temperature gradient today. Highs should be in the mid 20s north central and in the lower 40s southwest.
A dry cold front will begin to move through the TAF sites tonight from west to east. High pressure will weaken today ahead of the next cold front. An upper level trough situated across the central U. An associated cold front will move into the region tonight.
Surface analysis shows high pressure extending from the western Atlantic into the mid Atlantic states, with the Keys lying in a moderate but slowly weakening pressure gradient to the south of this ridge. Aloft, water vapor imagery shows deep ridging over the western Atlantic, but a sharp inverted trough located north of Hispaniola. Ridging aloft is not as strong over the Keys as it has been during the past few days, and this is reflected by the 00Z Key West sounding which found a weakened and elevated inversion up near 9K feet. High temperatures will climb into the lower 80s, which is near normal for this time of year.
This will scour out the low clouds and fog early this morning. With the return of sun, temperatures will reach into the lower 50s this afternoon. Lee troughing will result in strong south winds Monday with gusts to 45 mph.
Still expecting mid and high level cloud cover through the day today before the cold front approaches NW Georgia later this evening. /Issued 446 AM EST Sun Nov 22 2020/ Latest satellite imagery early this morning shows mid and high clouds increasing across the area in advance of a fairly weak area of low pressure approaching the Ohio Valley.
Another Cold Front and Cooler. Another cold front will move across West Central Texas today and bring cooler temperatures, along with a potential for rain. Highs today will be much cooler than yesterday, especially across the Big Country.
This appears to be the result of an increase in deep layer moisture and a coastal trough/coastal convergence. Temperatures are fairly cool aloft and occasional, but weak, mid-level impulses (troughing aloft) will also aid in convective development with ISOLD lightning storms also included in the forecast for today.
As the morning continues expect the low clouds and fog to lift and mix out with skies becoming partly cloudy by late morning and into the afternoon. Similar to yesterday some isolated to scattered low topped showers (Pops 20-40%) will again be possible during the afternoon, otherwise dry conditions with temperatures climbing into the lower 80s can be expected. The low clouds should lift and mix out after 16Z with broken Cigs in the 4-5kft range expected for the remainder of the day.
The upper ridge axis passes overhead and into the Plains. A Pacific upper trough will move onshore into the West this morning and be located over the Intermountain West tonight.
A trough of low pressure will pass over Northern California later this evening into Monday, and it appears chances of mountain precipitation will be mainly north of Yosemite. Some locally gusty winds are also a possibility in the favored passes and canyons in Kern County by Monday evening behind the trough, but forecast gusts will likely remain below advisory criteria.
For 12Z Aviation discussion below A broad area of rain and snow associated with weak PV advection with the upper trough will continue shifting across eastern MN and western WI this morning. Temperatures today and tomorrow will top out in the lower 30s to 40s, which is near to slightly above normal.
A cold front moving through the region today will result in elevated northeasterly winds, as well as rapidly deteriorating conditions at all terminals. Patchy MVFR fog is also expected to develop, with both the low ceilings/fog then expected to persist through the end of the forecast period. Due to the lack of a shrtwv trof the lift/mstr will be shallow and rain amounts still look to be 10" or less. Precip chances will dwindle Mon especially after 18Z with warmer high temps. Tue a strong mid-latitude cyclone will come out from the 4-Corners region with a 85-95kt 5h jet forecast to move across SE-E NM and W TX.
High pressure ridging aloft gives way to increasing high clouds ahead of an upper-level trough that moves across the region Monday. As the trough moves across the region Monday into Monday night, sufficient moisture and instability will support snow showers and minor snow accumulations across the Continental Divide and parts of southwest Montana.
204 AM MST Sun Nov 22 2020 MORNING DISCUSSION: Synoptic Setup: Forecast Begins with western to central Montana under a ridge which runs north into Alberta. Behind it is a trough stepping on shore of the Pacific Northwest. Farther west a pattern of progressive ridge-trough couplets exists over the northeast Pacific. Today through tonight: Ridge will move across the area keeping conditions dry.
Satellite imagery this morning shows areas of freezing fog have developed across Clearwater County, ID and across portions of northwest Montana. The axis of the upper level ridge will shift across central Montana this afternoon as the next weather system enters the Pacific Northwest. A splitting upper level trough will move across the Northern Rockies Sunday night into Monday.
Snow ramps up across the higher mountains tonight.
/Issued 446 AM EST Sun Nov 22 2020/ Latest satellite imagery early this morning shows mid and high clouds increasing across the area in advance of a fairly weak area of low pressure approaching the Ohio Valley.
Conditions are not expected to change much except for a slight decrease after 00Z when the sun sets and cooler temperatures allow for greater low level saturation. Due to the lack of a shrtwv trof the lift/mstr will be shallow and rain amounts still look to be 10" or less. Precip chances will dwindle Mon especially after 18Z with warmer high temps. Tue a strong mid-latitude cyclone will come out from the 4-Corners region with a 85-95kt 5h jet forecast to move across SE-E NM and W TX.
228 PM CST Sun Nov 22 2020 A deep trough over central Iowa and cloud cover to the east are progressing out of the area this afternoon.
255 PM CST Sun Nov 22 2020 As a weak low pressure system slowly pushes into the western Great Lakes, an area of backwash low clouds and cooler, northwesterly winds will continue to drag across these northern plains. A weak H5 ridge slides over the area tonight, providing some subsident warming and drying aloft, and helping to dissipate our low level cloudiness.
S/W ridging aloft and dry conditions should prevail across the region through Monday.
331 PM EST Sun Nov 22 2020 A weak coastal trough will move away from the area late tonight.
1146 AM CST Sun Nov 22 2020 18Z 22NOV20 TAFs High level clouds building in with mid level clouds expected late this afternoon as the cold front starts to move into the region.
1114 AM CST Sun Nov 22 2020 A broad area of rain and snow associated with weak PV advection with the upper trough will continue shifting across eastern MN and western WI this morning. Temperatures today and tomorrow will top out in the lower 30s to 40s, which is near to slightly above normal.
High pressure will settle over the area on Monday.
Low stratus was persistent over parts of the northwest and the north central, with patchy fog and temperatures limited to the lower 20s. Some high clouds will drift in tonight, with lows in the lower teens to lower 20s, and winds transitioning to southeasterly. Highs will be slightly warmer than today, ranging from the lower 30s north to lower 40s south central.
Expecting fair and dry conditions for Monday with high temps close to seasonal norms as high pressure builds in.
Behind the cold front, northwest surface winds were gusty around 20kts.
240 PM CST Sun Nov 22 2020 Upper level ridging will continue shifting east over the area through tonight. At the surface, a ridge axis of high pressure will shift east of the area tonight with return southerly flow developing. Otherwise with the approach of the west coast system, south winds will increase as the surface pressure gradient tightens due to low pressure developing leeward the Rockies.
313 PM EST Sun Nov 22 2020 Water vapor imagery highlights a short wave trough well to the east of the Bahamas and a flatter, long wave trough axis brushing through the Gulf of Mexico. Low level ridging extends west- southwest into the Carolinas, giving up ground to the weak cold front sliding east into the southern Appalachians. Portions of the Upper Keys have had several rounds of rain, while the Lower Keys remain rain-free. Temperatures are in the lower 80s for most locations with dewpoints in the lower 70s. A potent Pacific long-wave trough will push into the western United States tonight and Monday, amplifying the downstream ridging across the central United States. By Monday afternoon, northeasterly breezes will begin to freshen as high pressure strengthens over the eastern United States.
125 PM EST Sun Nov 22 2020 Rain is expected through tonight with crossing low pressure.
A few high clouds are cutting through the upper level ridge. 1020 AM MST Sat Nov 21 2020 (22/18Z TAF period) VFR conditions prevail, with some high clouds passing through an upper level ridge. /ISSUED 408 AM MST Sun Nov 22 2020/ High pressure ridging aloft gives way to increasing high clouds ahead of an upper-level trough that moves across the region Monday. As the trough moves across the region Monday into Monday night, sufficient moisture and instability will support snow showers and minor snow accumulations across the Continental Divide and parts of southwest Montana.
1020 AM EST Sun Nov 22 2020 Water vapor imagery highlights a short wave trough east of the Bahamas and a flatter, long wave trough axis brushing through the Gulf of Mexico. Low level ridging extends west-southwest into the southeastern United States, giving up ground to the weak cold front sliding southeast through the Mississippi River Valley. This morning's KKEY RAOB sampled falling heights at all SGL, corroborating the ridge's retreat and the approaching lower heights aloft. High pressure ridge extending from the western Atlantic into the mid Atlantic states will weaken this afternoon and tonight, as a weak cold front approaches the Eastern Seaboard and moves down the Florida peninsula.
1129 AM CST Sun Nov 22 2020 An approaching cold front will be losing its structure upon arrival tonight, with high pressure bridging the boundary.
217 PM CST Sun Nov 22 2020 Cooler and more moist conditions has arrived for southeast New Mexico and much of west Texas as a cold front heads toward the Rio Grande River in southwest Texas tonight. The combination of forcing associated with a 700 millibar trough across the Desert Southwest and warm advection above and north of the front will increase the chances for light rain, drizzle and fog tonight and Monday morning across the region.
253 PM CST Sun Nov 22 2020 Thick mid to high clouds have now overspread Northwest Alabama ahead of a cold front currently stretched east of Memphis and just west of Nashville. Short term guidance suggests the front will make it south of the forecast area by midnight, and northwest continental flow will advect cooler and drier conditions into the area. Will begin the Thanksgiving week cool and dry, as an upper level trough axis slides east off the Atlantic coast and northwest flow remains dominant on Monday.
A trough and cold front on Monday will bring snow to the mountains with the possibility of some light precipitation in the valleys.
A dry cold front will begin to move through TAF sites tonight from west to east. High pressure will weaken today ahead of the next cold front. An upper level trough situated across the central U. An associated cold front will move into the region tonight.
1019 AM MST Sun Nov 22 2020 Current surface analysis shows trough over the eastern Dakotas. Upper level analysis shows trough moving east of the region, with mostly clear skies. Ridging to the west of the region will move east over the area later today and tonight.
This will be in response to the approach of a highly-amplified upper trough moving into Nevada and Sonora by Monday afternoon. Gusty south wind may speed the return of boundary layer and lower level moisture that was banked against the higher terrain of New Mexico and west Texas on Sunday.
A few high clouds are cutting through the upper level ridge. /ISSUED 408 AM MST Sun Nov 22 2020/ High pressure ridging aloft gives way to increasing high clouds ahead of an upper-level trough that moves across the region Monday. As the trough moves across the region Monday into Monday night, sufficient moisture and instability will support snow showers and minor snow accumulations across the Continental Divide and parts of southwest Montana.
Prevailing VFR should return to the terminals after 16Z on Monday as a cold fronts moves south through the region with winds backing to the north and increasing to 10 to 12 knots. As the morning continues expect the low clouds and fog to lift and mix out with skies becoming partly cloudy by late morning and into the afternoon. Similar to yesterday some isolated to scattered low topped showers (Pops 20-40%) will again be possible during the afternoon, otherwise dry conditions with temperatures climbing into the lower 80s can be expected.
High pressure will build across the region today ahead of the next trough arriving Monday afternoon.