Aikyam-Lab/Synoptic-Bench huggingface dataset:
Water vapor imagery shows an impressive upper jet digging through the base of the upper trof into the lower MS Valley. Models show the large scale forcing/ascent maxing between now and 12-15z over western MO, and then forcing weakens and shifts northward and northeastward through the remainder of the day as the upper low/trof eject northeastward across southern IL and then into the western OH Valley. Otherwise an area of snow will spread from south central MO into east central MO this morning attendant with a vort max rotating northeast through the base of the upper trof.
Sfc weather map shows low pressure across CONUS's mid-Mississippi valley. An inverted trough extends nwd into MN this morning that continues to touch of precip east of this CWA. We are left with a low cloud shroud & fog west of this system as a weak ridge of high pressure is situated across the Dakotas.
Main upper level low has transitioned east as well and deepest moisture and larger scale energy. Deeper moisture and some energy associated with mid level rotation (apparent on satellite) may continue to support flurries or even a few pockets of light freezing drizzle in our far east this morning, but this appears to be transitioning east as well.
The morning surface analysis shows an area of low pressure progressing northeast across Missouri and occlusion starting to push through the Tennessee and Ohio Valleys. The upper level low and vorticity will keep lift going through the period and even a period of lower level omega will be seen tonight. Given the warm weather heading into this would think perhaps the higher terrain in the far southeast could see some slush on grassy surfaces, but outside that ground temperatures will be too warm. Mostly cloudy skies look to be on tap across eastern Kentucky through the majority of the period, given the general troughiness that will control across the Ohio and Tennessee valleys. Several short wave troughs will traverse the flow, bringing reinforcing cloud cover, as well as bouts of light precipitation at times.
327 AM MST Fri Jan 24 2020 Sharp ridge flattening over the area today which maintains a leeside trough across the central zones. Ridge has brought warm air with it which will support temperatures in the 45 to 50 degree range. Dry throughout the day but the passage of the ridge axis into the Dakotas will support some moisture reaching the mountains by afternoon. Chance for snow takes a break Saturday midday through Saturday night as the upper low over northeast Montana wraps dry air around the backside.
Multiple fast moving s/wv troughs affecting area next several days.
Upper-level closed-low pressure system continue to spin over the middle/lower Mississippi Valley, slowly moving northeast this morning.
Light to moderate northwesterly winds will prevail through the day before becoming calm overnight as high pressure becomes centered overhead. High pressure begins nudging into the region keeping skies clear and conditions dry. Upper trough over the eastern CONUS continues to slide eastward with mostly zonal flow over SE TX / SW LA heading into the weekend.
341 AM MST Fri Jan 24 2020 Overnight WV/IR imagery loop showed a potent upper low centered over the Mid-MS Valley and a upper ridge across the Intermountain West. Short range models are in good agreement with the steady northeast track of the upper low through the OH Valley and eastern Great Lakes. Meanwhile, the upper ridge to the west weakens as it translates east through the Rockies and High Plains.
and Saturday Upper low moving from near Saint Louis to southwest Lower Michigan will produce periods of snow today and tonight.
214 AM MST Fri Jan 24 2020 500 mb RAP analysis and water vapor imagery showed an upper closed low over the Ozarks of southern Missouri and northern Arkansas overnight. To the west, a ridge built over the Great Basin, placing the tri-state region under northwest flow. Dry conditions are expected to prevail, with high temperatures in the low 40s to low 50s from east to west. Ridging rebuilds over the Great Basin on Saturday and advances to the Rockies by Saturday night. High pressure tries to slide into the area Saturday night as temperatures fall into the 20s.
High pressure begins nudging into the region keeping skies clear and conditions dry. Upper trough over the eastern CONUS continues to slide eastward with mostly zonal flow over SE TX / SW LA heading into the weekend.
412 AM EST Fri Jan 24 2020 The morning surface analysis shows an area of low pressure progressing northeast across Missouri and occlusion starting to push through the Tennessee and Ohio Valleys. The upper level low and vorticity will keep lift going through the period and even a period of lower level omega will be seen tonight. Given the warm weather heading into this would think perhaps the higher terrain in the far southeast could see some slush on grassy surfaces, but outside that ground temperatures will be too warm.
351 AM CST Fri Jan 24 2020 A strong upper level low centered across southern Missouri this morning will shift eastward into southeast Illinois by early this evening. Meanwhile upper level ridging will translate east through the Rockies toward the western High Plains. At the surface a nearly stationary arctic cold front will bisect our immediate area from northwest to southeast. Light westerly downslope flow and sunshine will boost highs into the lower and mid 40s. warm air spreading east of the higher terrain to the west via downslope flow will push highs well into the 40s across western and southwest Nebraska. Some of this air will spread into north central Nebraska with highs in the lower to mid 30s. The lower levels below 700mb will be quite dry however, so probably more virga than anything.
/EC/ Today through tonight: as a closed low crosses the Middle MS Valley today, cyclonic flow and weak low level cold advection will support gusty west winds and stratus persisting for locations mainly north of the I-20 corridor. For tonight, the low will pull away allowing skies to clear. Lows tonight should drop to near or just below freezing for the majority of the forecast area, so there may need to be some consideration given to the possibility of freezing fog where fog becomes dense enough.
506 AM EST Fri Jan 24 2020 The morning surface analysis shows an area of low pressure progressing northeast across Missouri and occlusion starting to push through the Tennessee and Ohio Valleys. The upper level low and vorticity will keep lift going through the period and even a period of lower level omega will be seen tonight. Given the warm weather heading into this would think perhaps the higher terrain in the far southeast could see some slush on grassy surfaces, but outside that ground temperatures will be too warm. Mostly cloudy skies look to be on tap across eastern Kentucky through the majority of the period, given the general troughiness that will control across the Ohio and Tennessee valleys. Several short wave troughs will traverse the flow, bringing reinforcing cloud cover, as well as bouts of light precipitation at times.
427 AM CST Fri Jan 24 2020 Today through tonight: as a closed low crosses the Middle MS Valley today, cyclonic flow and weak low level cold advection will support gusty west winds and stratus persisting for locations mainly north of the I-20 corridor. For tonight, the low will pull away allowing skies to clear. Lows tonight should drop to near or just below freezing for the majority of the forecast area, so there may need to be some consideration given to the possibility of freezing fog where fog becomes dense enough.
548 AM CST Fri Jan 24 2020 An upper low now over southern MO will shift away from the area today. Light rain/drizzle has been giving way to a band of snow pivoting around the low.
Soundings suggest there may be a loss of ice leading to some freezing drizzle in spots. The low pressure system will be moving northeast today into tonight making it to the southern Lake Michigan/southern Michigan area by 12Z Saturday. A few light snow showers or wintry mix will persist for Ashland, Iron and Price Counties Saturday night as a large low pressure system drifts over Lake Huron.
417 AM MST Fri Jan 24 2020 09Z upper level analysis has very amplified flow across the CONUS with ridge to the west of the Northern Plains, and trof to the east. Thin high clouds are spilling over the western ridge across northeastern WY with low stratus present across the SD plains. At the surface, high pressure is present across the eastern Dakotas with weak lee trof across eastern Montana into northeastern WY. Some areas of fog are present across the SD plains under the low stratus. Temperatures overnight will be a bit warmer, especially across western areas. Little accumulation is expected except for minor amounts across the higher Black Hills.
306 AM CST Fri Jan 24 2020 An upper low now over southern MO will shift away from the area today. Light rain/drizzle has been giving way to a band of snow pivoting around the low.
Initially colder temperatures today quickly begin to give way to progressively warmer temperatures through the weekend. Have kept with the lower side of guidance also due to stratus being slow to clear the area. Only a narrow zone of a relative dry airmass will allow for partial clearing into the evening and overnight period as the upstream ridge dampens within broader northwest flow aloft. Even so, some relative height rises suggest an overall warmer airmass is lifted poleward.
539 AM CST Fri Jan 24 2020 A strong upper level low centered across southern Missouri this morning will shift eastward into southeast Illinois by early this evening. Meanwhile upper level ridging will translate east through the Rockies toward the western High Plains. At the surface a nearly stationary arctic cold front will bisect our immediate area from northwest to southeast. Light westerly downslope flow and sunshine will boost highs into the lower and mid 40s. warm air spreading east of the higher terrain to the west via downslope flow will push highs well into the 40s across western and southwest Nebraska. Some of this air will spread into north central Nebraska with highs in the lower to mid 30s. The lower levels below 700mb will be quite dry however, so probably more virga than anything.
But even with the high pressure, we won't clear out right away. Models show the first short wave trof developing over the western Dakotas on Saturday, and that looks to push a weak sfc front through the plains.
Showers continue across the area as an area of positive vorticity advection swings through the broad trough/ upper low. The upper low is currently centered over north central Arkansas and south central Missouri. There should be a break in the rain between the broad rain shield that we've experienced over the last several hours and the showers associated with the upper low. The upper low will wobble northeastward along the Ohio River Valley today and be located along the central Illinois/ Indiana border by 00z.
For temperatures, little in the way of airmass change combined with the low clouds will keep our diurnal ranges small.
244 AM MST Fri Jan 24 2020 500 mb RAP analysis and water vapor imagery showed an upper closed low over the Ozarks of southern Missouri and northern Arkansas overnight. To the west, a ridge built over the Great Basin, placing the tri-state region under northwest flow. Dry conditions are expected to prevail, with high temperatures in the low 40s to low 50s from east to west. Ridging rebuilds over the Great Basin on Saturday and advances to the Rockies by Saturday night. High pressure tries to slide into the area Saturday night as temperatures fall into the 20s. A couple upper level short wave troughs will move through the northwest flow during this period.
However, some light freezing drizzle is possible in some valleys of Southwest Montana this morning before the more widespread threat for rain and snow moves into that area this afternoon. This set-up could cause some patchy freezing drizzle in those saturated valleys (West Yellowstone valley is already saturated, as they are currently reporting fog); however, significant impacts are not expected. As the moisture increases throughout the airmass, the threat for freezing drizzle in the mentioned valleys will decrease, leaving a better chance for snow.
430 AM MST Fri Jan 24 2020 Persistent mid cloud deck across the far eastern plains associated with upper jet on the back side of the plains upper low will gradually shift eastward through the morning. and predominantly 30s and 20s across the higher mountains. Still looking at only an inch or two at best across the higher peaks and passes. Otherwise, kept low temperatures on the warmer side of guidance given mid/high cloud cover through majority of the night.
321 AM PST Fri Jan 24 2020 Isolated to scattered light rain or higher elevation snow showers are expected early today as low pressure moves over northern California and Nevada.
623 AM EST Fri Jan 24 2020 A deep plume of low level moisture will accompany a low pressure system into the region this taf period. The likelihood for LIFR restrictions will increase late afternoon or evening as the low advances in lower Michigan. Closed low over southern Missouri will modulate Southeast Michigan weather through the weekend. Upper low will then meander toward Lower Michigan tonight through Saturday, much of this period on the drier side for most areas given the degree of dry air that has already wrapped into the core of the circulation.
As an upper trough continues to move east, high pressure will build over Texas, and a warm-up will begin. Then, winds from the south will continue to pull warmer air from the south, into West Central Texas.
Primary impacts will likely be relegated to secondary roadways, however periods of moderate snowfall may see highways, interstates, and primary local roadways accumulate snowfall with many locations reporting road temperatures at or just below freezing currently.
Meanwhile, local radars are detecting scattered showers along the Lower and Middle keys, and extending both north and south for over 20 nm. Otherwise, a large region of high pressure sprawling down the entire eastern seaboard and the Florida Peninsula will slide into the western Atlantic Ocean resulting in a weak pressure pattern tonight. Thereafter, a decaying cold front will move eastward through the Gulf of Mexico and limp across our entire region by late Saturday, with high pressure to follow for the balance of this weekend. With that, after some rainfall in the Lower and Middle Keys early this morning, little if any rainfall is expected for the rest of this forecast period. High temperatures will average in the mid 70s, with overnight lows in the lower to mid 60s.
The ridge axis moved over the Northern Rockies last night causing a momentary break in showers. As precipitation moves back into the region due to a weak cold front today, the mountains will experience snow and the valleys receive a wintry mix. Dependent on how strong the valley inversions are a few locales could have light freezing rain. The freezing rain will mainly be a nuisances to walkways and parking lots. The fog and freezing rain potential will lessen throughout the morning. Another low amplitude ridge of high pressure slides over the Northern Rockies by Saturday. This ridge will cause the shower activity to decrease in intensity and coverage, but will not create a widespread dry period.
Still expecting general accumulations of 3 to 6 inches for the higher mountain elevations, mainly through sunrise Saturday. As the midlevel trough moves east, it gets stretched and split taking a chunk of the energy into MT, and the rest into northern CO.
This system looks to produce a wide variety of precip types across the region today with rain, rain/snow mix, snow and even a brief period of freezing rain likely. Before the systems arrival however, widespread low clouds has allowed for pockets of freezing drizzle and this has been observed from around Rigby north towards Monida Pass and up US-20 towards Island Park. In the mountains, it will be all snow but across the Magic Valley model soundings show the potential for a brief period (3-4 hours) of freezing rain from around Burley east along the I-84/86 corridors over to around Cold Water. Gradual warming will allow this to eventually change over to rain by the afternoon but nevertheless the freezing rain potential could cause some hazardous travel conditions.
Highs may climb into the lower 50s across portions of central KS while much of northeast KS remains in the 30s. This will bring an increase in pops to the region although there has been a subtle trend southward with the mid/upper trough which may keep the higher impacts south of our forecast area. A well-defined low pressure center is located over C MO early this morning. The low is spreading MVFR cigs (generally around 1,500ft) across all areas.
/Issued 228 AM CST Fri Jan 24 2020/ Region of light rain/snow continues to push eastward across northeast Oklahoma and northwest Arkansas as the upper low centered over northwest Arkansas slowly exits the region.
For tonight, an upper level trough will move across the area. A developing downslope component just off the deck should also promote late day warming, but not sure we'll see the lower 50s suggested by the latest model averages.
450 AM MST Fri Jan 24 2020 Low cloud and fog over the eastern zones for most of the night, beginning to break up as upper ridge pushes over the state. With the low level inversion, could also see some valley fog overnight. Weak cold front dips into the northeast corner of the state on Saturday with another chance for light precipitation.
331 AM MST Fri Jan 24 2020 09Z upper level analysis has very amplified flow across the CONUS with ridge to the west of the Northern Plains, and trof to the east. Thin high clouds are spilling over the western ridge across northeastern WY with low stratus present across the SD plains. At the surface, high pressure is present across the eastern Dakotas with weak lee trof across eastern Montana into northeastern WY. Some areas of fog are present across the SD plains under the low stratus. Temperatures overnight will be a bit warmer, especially across western areas. Little accumulation is expected except for minor amounts across the higher Black Hills.
423 AM MST Fri Jan 24 2020 500 mb RAP analysis and water vapor imagery showed an upper closed low over the Ozarks of southern Missouri and northern Arkansas overnight. To the west, a ridge built over the Great Basin, placing the tri-state region under northwest flow. Dry conditions are expected to prevail, with high temperatures in the low 40s to low 50s from east to west. Ridging rebuilds over the Great Basin on Saturday and advances to the Rockies by Saturday night. High pressure tries to slide into the area Saturday night as temperatures fall into the 20s. A couple upper level short wave troughs will move through the northwest flow during this period.
627 AM EST Fri Jan 24 2020 The morning surface analysis shows an area of low pressure progressing northeast across Missouri and occlusion starting to push through the Tennessee and Ohio Valleys. The upper level low and vorticity will keep lift going through the period and even a period of lower level omega will be seen tonight. Given the warm weather heading into this would think perhaps the higher terrain in the far southeast could see some slush on grassy surfaces, but outside that ground temperatures will be too warm. Mostly cloudy skies look to be on tap across eastern Kentucky through the majority of the period, given the general troughiness that will control across the Ohio and Tennessee valleys. Several short wave troughs will traverse the flow, bringing reinforcing cloud cover, as well as bouts of light precipitation at times.
429 AM MST Fri Jan 24 2020 Overnight WV/IR imagery loop showed a potent upper low centered over the Mid-MS Valley and a upper ridge across the Intermountain West. Short range models are in good agreement with the steady northeast track of the upper low through the OH Valley and eastern Great Lakes. Meanwhile, the upper ridge to the west weakens as it translates east through the Rockies and High Plains.
416 AM EST Fri Jan 24 2020 A low-pressure system will move from southeast Louisiana this morning will lift northeast. This low will bring a coastal front onshore today and a cold front will shift off the coast late Friday night. High pressure will build over the area Saturday through the end of the week.
216 PM CST Fri Jan 24 2020 Large closed upper low over the Ohio Valley has sent several waves of showers through the region early this afternoon and this will continue into the evening hours until the primary upper wave axis finally exits the region to the northeast overnight. Most shower activity will be confined to areas along and north of I-40 in closer proximity to the upper low but could reach as far south as the AL line at times. Shallow low-level instability will allow for some brief downpours with this activity, and this combined with very low freezing levels has even resulted in some small hail in the heavier showers. Small hail will remain a possibility with the stronger showers this afternoon, and then later this evening there could be some snow/graupel mixed in as the freezing level drops further.
1042 AM EST Fri Jan 24 2020 Water vapor imagery highlights a closed cyclone working eastward toward the Ohio River Valley, northeast of broad cyclonic curvature spreading east into the western Gulf of Mexico. From synopsis, a weak pressure pattern will evolve across the coastal waters of the Florida Keys this afternoon and tonight, as a decaying cold front limps southeastward through the Gulf of Mexico.
343 PM EST Fri Jan 24 2020 A cold front will push offshore tonight followed by high pressure. However, should see an increasing risk of a few thunderstorms through this evening as a cold front across western GA approaches from the west, pushing offshore around midnight. Rain will quickly end from southwest to northeast with the passage of the front with cooler and drier air moving in by daybreak, although some low clouds could linger much of the night, especially across SC.
Increasing south winds will also keep temperatures up with overnight lows in the low to mid 40s.
(This afternoon through Saturday) Large upper low over the Midwest/Great Lakes region continues to move eastward and away from our area.
306 PM EST Fri Jan 24 2020 The deep closed low is currently centered over southern Illinois with the moist low level jet flowing north over eastern Kentucky. West of the low level jet, precipitable water values drop to under an inch, but pockets near the center of circulation are seeing values over 0. Not expecting many issues tonight other than wet roadways as temperatures stay slightly above freezing.
204 PM CST Fri Jan 24 2020 Upper closed low early this afternoon was located near St. For tonight, the upper low will slowly lift away from the region.
The low will then track to Lake Huron for Sat afternoon. The negative tilt upper trough will send a vorticity maximum from lower MI and nw Ohio across srn WI late this afternoon and tnt followed by other vorticity lobes that will affect the region into Sat AM. A TROWAL and mid level frontogenesis will accompany the upper low across srn WI.
Skies should slowly clear from southwest to northeast through the day as the upper low associated with these clouds moves away.
1018 AM MST Fri Jan 24 2020 Persistent mid cloud deck across the far eastern plains associated with upper jet on the back side of the plains upper low will gradually shift eastward through the morning. and predominantly 30s and 20s across the higher mountains. Still looking at only an inch or two at best across the higher peaks and passes. Otherwise, kept low temperatures on the warmer side of guidance given mid/high cloud cover through majority of the night.