Aikyam-Lab/Synoptic-Bench huggingface dataset:
252 PM EST Mon Dec 14 2020 | Upper-level flow will become quasi-zonal this evening, while north to northwest surface winds will advect cooler, drier air across the CWA.
This evening a longwave 500 mb trough will be moving from the four corners region and turning into a closed low in northeast New Mexico by sunrise. Ahead of the low all of the models are in pretty good agreement that a 700 mb frontogenetic band will be developing and saturating between 03-09Z roughly in an area from Lamar, Colorado to WaKeeney. The frontogentic band starts to move south and eastward as the upper low approaches and we could see areas of light snow start to become more widespread through our northwest and north central zones. Tuesday as the upper low moves through the Texas panhandle into Oklahoma another 700 mb frontogentic band will develop and fill in mainly from highway 50 on south.
An area of high pressure will translate through the region tonight, leading to light winds and calm conditions. A number of ensemble members from the high-resolution models are indicating accumulation amounts between 1 to 2 inches possible from Taconite Harbor to Grand Portage.
130 PM CST Mon Dec 14 2020 (Issued 130 PM CST Mon Dec 14 2020) Tonight through Tuesday night: High pressure will continue to settle southeast into the area heading into tonight. Lows tonight should end up in the teens and upper single digits, though with the high overhead, a few of the usual cool spots might end up several degrees cooler, especially if they have a deeper snowpack. Mid and high level clouds will remain in place tomorrow morning as high pressure starts to push east of the area.
1051 AM EST Mon Dec 14 2020 A strong cold front will move east of the region today, with breezy winds through the afternoon. High pressure will briefly bring dry weather tonight and Tuesday.
Temperatures will drop to near or just below freezing by evening, so very minor road impacts won't be impossible, but not planning on any advisories/headlines.
1132 AM EST Mon Dec 14 2020 A shallow and weakening cold front is making headway through the eastern Gulf. By the time that line of showers reaches our Gulf waters tonight, they will mainly be confined to the deeper and warmer offshore Gulf waters. The frontal wind shift is forecast to run out of steam on Tuesday morning near the Lower Keys, where an isolated shower is possible. One other possibility given dewpoints in the lower 70s over sea- surface temps in the mid-upper 60s is the late-night development of sea fog or low stratus over the shallow, cool Gulf waters north of the Lower and Middle Keys. A brush of fog over the Lower/Middle Keys cannot be ruled out, but guidance is mostly avoiding the needed push of north wind all the way into the Keys.
Weak ML/UL ridging tonight and Tuesday will quickly break down as progressive flow brings another upper low into the plains later in the day.
Very weak upper and mid-level ridging begins to build in over the region through the near term with a mainly southwesterly flow aloft existing above 500mb. In the lower levels, moderate cold air advection takes over in the wake of the frontal passage with a more northerly flow being dominant. At the surface, ridging builds into the region from the north through Tuesday. This could impact low temps across the region being slightly warmer than expected in some areas. That being said, low temps tonight are expected to be in the low to upper 30s northwest of I-65 and upper 30s to low 40s southeast. In the lower levels, a gradual shift to flow being more southwesterly will bring increasing Gulf moisture into the region through Tuesday as the upper level system approaches from the west.
1105 AM CST Mon Dec 14 2020 243 AM CST Relatively quiet weather will continue through Tuesday as high pressure builds into the region. This will also place a limit on the amount of nocturnal cooling tonight, so confidence on nighttime lows is medium at best with other parameters (high pressure passing across southern Wisconsin) still favorable for decent radiational cooling.
247 PM EST Mon Dec 14 2020 A strong cold front will move east of the region today, with breezy winds through the afternoon. High pressure will briefly bring dry weather tonight and Tuesday.
327 PM EST Mon Dec 14 2020 High pressure will build in briefly through Tuesday.
Sub freezing temperatures are expected area wide with the coldest areas in the middle 20s. Tomorrow afternoon will be slightly warmer ranging from the low 40s in East Arkansas to the low 50s in Northeast Mississippi. Yet another deep trough and cutoff low will start to move into the Southern Plains early tomorrow resulting in deepening Southwest flow across much of Texas then across the lower and middle Mississippi River Valley. The low is forecast to track due East over Oklahoma tomorrow then turn Northeast over Missouri tomorrow night.
A warmer air mass will begin to work its way into the region on Tuesday, bringing temperatures back closer to average.
With surface temperatures below freezing, this could lead to a light dusting at best.
A weak front has meandered into portions of Central Florida this evening with a pre-frontal trough pushing into Southwest Florida. Short term (Today through Tuesday Evening): A 500mb ridge remains over the area through the day tomorrow. At the surface, there is a weakening cold front moving into the area. The cold front is forecast to move into the area tonight, and stall. With the ridge overhead, the dynamics are poor, and the front should be mostly dry, but we may be able to get a few isolated showers tonight.
Therefore, there may be a light dusting of snow along the Canadian border, flurries, or nothing (albeit the low chances for snow with the feature). A warm up into the 30s Thu will be followed by the approach of a cold front in time for Fri. Eventually winds shift the southwest later in the TAF period at KDVL as low pressure moves east.
00z KUNR sounding saturated in the low levels and weak east upslope component to boundary layer may be contributing to snowfall character. Western CONUS upper trough will re-build east into the region this week, supporting mild temps and mainly dry weather after Tues in NW flow. WAA will ensue Tue, with warmer highs mainly in the 30s. Clipper system will slide SE on the front side of the ridge Wed, supporting a warmer day per deeper mixed flow.
That being said, the highest PoPs remain west of HWY 281 and then expand eastward mainly after midnight, with the most widespread PoPs expected in the morning hours tomorrow between 12Z and 18Z.
416 PM MST Mon Dec 14 2020 The upper trough axis extended from northern WY to northern AZ. A stationary front was located from western MT to central NE with modest pressure falls across CO/NM ahead of approaching trough. Although the pattern is generally more active compared to the last few weeks, quick moving upper level troughs, with a limited moisture tap, will produce little or minimal snowfall amounts for the eastern plains and most of the high valley locations west of the I-25 corridor.
with low temperatures dropping into the lower to middle 20s tonight and highs only reaching the middle 30s on Tuesday.
A high pressure ridge and a fair amount of cloud cover have controlled much of the weather conditions we've seen today across the forecast area.
/Issued 312 PM CST Mon Dec 14 2020/ A low pressure system. rain/snow chances will become possible mid to late Tuesday morning as the wave nears the CWA and then spreads over the CWA Tuesday afternoon/evening before tapering off late evening with the exiting upper low. The greater snowfall potential looks to be along and west of Highway 75 Tuesday late morning through the afternoon hours where temps in the lower 30s are forecast. Behind the exiting upper low Tuesday night. A ridge of high pressure then fills in over the region for the second half of the week with drier conditions and a warming trend forecast.
As the trough advances toward the Plains tonight into Tuesday, it will become neutral or even develop a slight negative tilt as a closed center develops at H5 across southern KS and OK.
655 PM EST Mon Dec 14 2020 High pressure and a dry but cool airmass will remain in place across the region through Tuesday.
312 PM CST Mon Dec 14 2020 A low pressure system. rain/snow chances will become possible mid to late Tuesday morning as the wave nears the CWA and then spreads over the CWA Tuesday afternoon/evening before tapering off late evening with the exiting upper low. The greater snowfall potential looks to be along and west of Highway 75 Tuesday late morning through the afternoon hours where temps in the lower 30s are forecast. Behind the exiting upper low Tuesday night. A ridge of high pressure then fills in over the region for the second half of the week with drier conditions and a warming trend forecast.
215 PM MST Mon Dec 14 2020 The upper trough axis extended from northern WY to northern AZ. A stationary front was located from western MT to central NE with modest pressure falls across CO/NM ahead of approaching trough. Although the pattern is generally more active compared to the last few weeks, quick moving upper level troughs, with a limited moisture tap, will produce little or minimal snowfall amounts for the eastern plains and most of the high valley locations west of the I-25 corridor.
Temps range from the lower teens across central Minnesota to the upper teens across the south.
Light snow will linger today, especially in the higher terrain, as a deep trough of low pressure exits the Northern Rockies and flow becomes more westerly. This is just the beginning, as another low pressure system is spinning off the coast of British Columbia. The low pressure center will stay to our north, so forcing will be weak and snow accumulations will be light, with the most snow falling in the higher terrain. Also, temperatures remain above average, with daytime highs topping out above freezing for valley locations.
554 PM CST Mon Dec 14 2020 A mid/upper trough over the Central Great Basin area today will move into the Central Rockies tonight before emerging over the Southern Plains states on Tuesday. Large-scale forcing for ascent will overspread the area during the mid to late morning hours on Tuesday as the mid/upper trough approaches from the west. Accumulations are expected to range from 1- 3 inches with the highest amounts over our southwest counties which is similar to the previous snowfall event and very similar to the previous forecast. Any lingering snow in the evening should rapidly diminish as the mid/upper trough translates eastward away from the area. Trended minimum temperatures down where confidence in accumulating snow is the highest.
The cloud cover limited our warming potential significantly this afternoon, subsequently temperatures were floundering in the lower 20's over most of the region at 3 PM. We're forecasting only a trace to 2 inches, with the highest amounts toward Albion and Columbus.
244 PM MST Mon Dec 14 2020 Main concern will be the next round of light snow tonight and Tuesday as an upper trough in the Great Basin ejects across the Rockies. Models show the system briefly becoming a closed low Tuesday over the Texas/Oklahoma panhandle then moving east. Furthest west with placement is the GEFS mean from roughly McCook to Burlington, while the furthest east is the HRRR with the higher totals just east of the area, with the rest of the models somewhere in between.
To complicate matters further, the CAA becomes neutral and reverses after midnight downstream of an approaching upper level trof, with the low level cloud cover forecast to redevelop/expand back to the north. This upper trof is progged to traverse the SRN Plains tomorrow, then eject NE through the Mid MS River Vally tomorrow night. The low is expected to track EWD through the evening along a N-S oriented CDFNT, along with a swath of rain/embedded showers. While highs tomorrow are expected to be warmer than today, readings will be tempered by the widespread cloud cover. Brisk and gusty NW winds are expected WED in the wake of the front, with highs forecast to reach the lower to perhaps mid 50s.
A cold front will stall over the peninsula this evening, with weak high pressure building in behind the front on Tuesday. An area of low pressure and associated cold front will move through the eastern Gulf waters and southeast U.
656 PM EST Mon Dec 14 2020 High pressure will build in briefly through Tuesday.
Otherwise, with a cooler airmass moving in, temperatures will drop off nicely tonight with temperatures near freezing in many of the deserts including Tucson.
Temperatures in the upper 60s to low 70s this evening will fall into the upper 50s northwest of the I-4 corridor into late tonight, with lows mainly in the low 60s farther south across east central Florida.
In the upper levels, SW flow will begin to develop early Tuesday morning as a deep upper trough crosses the Rockies and begins to move through the Plains. The cloud cover across the region will limit warming on Tuesday with highs expected to range from the low 40s in the NW to low 50s in the SE.
459 PM MST Mon Dec 14 2020 Winter weather continues over the western slope this afternoon as a trough moves through the central Rockies. The axis of the trough remains just to our west as of 2pm, and this feature will swing through western Colorado this evening and pass east of the Continental Divide by midnight. Forecast precipitation remains on track, with a coating to a half an inch or so in the valleys through tonight, and 2-5 inches in the higher terrain.
Latest storm system continues to move out of the area as ridging builds into the region. This will bring periods of overnight and morning dense valley fog and slightly warmer high temperatures over the next few days.
The upper low that brought widespread snow to the region should completely exit the state by this evening. Model agreement looks to replace this low with some short term ridging for the remainder of today into Tuesday, which allows part of the state to dry out a bit. For tonight into Tuesday morning, clear skies and cold overnight temperature will present possible areas of freezing fog in the valleys of northern and central Nevada. A weak upper wave will flatten the ridge a bit allowing for some possible light snow showers Tuesday night. However, only parts of the higher elevations in northern Elko and Humboldt counties have a chance of light snow showers with values of an inch or less present.
Made some tweaks to the low temperatures. Sub freezing temperatures are expected area wide with the coldest areas in the middle 20s. Tomorrow afternoon will be slightly warmer ranging from the low 40s in East Arkansas to the low 50s in Northeast Mississippi. Yet another deep trough and cutoff low will start to move into the Southern Plains early tomorrow resulting in deepening Southwest flow across much of Texas then across the lower and middle Mississippi River Valley. The low is forecast to track due East over Oklahoma tomorrow then turn Northeast over Missouri tomorrow night.
556 PM EST Mon Dec 14 2020 High pressure will build in briefly through Tuesday.
529 PM CST Mon Dec 14 2020 Early this afternoon Canadian high pressure was building into northern Minnesota, poised to cross the Upper Mississippi Valley tonight and then depart over the Great Lakes on Tuesday. These clouds will set the stage for a tricky low temperature forecast as the high settles overhead and winds decouple. The high will drift off to the east on Tuesday with ridging still extending into the forecast area. Slightly warmer conditions are expected starting mid-week.
High pressure is building in from the north, with colder, drier air advecting into the mid state, but the boundary layer moisture has been reluctant to depart from us. But nearly all of it is concentrated in the lowest 3 kft or so. The low pressure system that brought rain and colder temperatures to Middle Tennessee is now far to our east and high pressure is building in from the north. But the low- level moisture that is keeping MVFR ceilings in place across the mid state is being quite pesky.
911 PM EST Mon Dec 14 2020 High pressure will build in briefly through Tuesday.
951 PM EST Mon Dec 14 2020 High pressure and a dry but cool airmass will remain in place across the region through Tuesday.
/issued 217 PM CST Mon Dec 14 2020/ This morning all of the observation sites were at or below freezing with low temperatures ranging from the mid 20s to the teens. The wind today has already shifted out of the south supporting a LLJ over the lower Trans Pecos and Permian Basin bringing in breezy conditions today through tonight. Low temperatures tonight will a bit warmer with most locations staying in the upper 20s to mid 30s. Another upper level trough will move out of NorCal area into the Desert SW and over the TX Panhandle by Tuesday. 850 mb winds aided by a frontal passage will support wind advisory conditions for the Permian Basin, southeast New Mexico, and the Upper Trans Pecos from the aforementioned trough.
/Issued 252 PM EST Mon Dec 14 2020/ Upper-level flow will become quasi-zonal this evening, while north to northwest surface winds will advect cooler, drier air across the CWA.
422 PM MST Mon Dec 14 2020 Western CONUS upper trough will re-build east into the region this week, supporting mild temps and mainly dry weather after Tues in NW flow. WAA will ensue Tue, with warmer highs mainly in the 30s. Clipper system will slide SE on the front side of the ridge Wed, supporting a warmer day per deeper mixed flow.
236 PM MST Mon Dec 14 2020 Winter weather continues over the western slope this afternoon as a trough moves through the central Rockies. The axis of the trough remains just to our west as of 2pm, and this feature will swing through western Colorado this evening and pass east of the Continental Divide by midnight. Forecast precipitation remains on track, with a coating to a half an inch or so in the valleys through tonight, and 2-5 inches in the higher terrain.
We should expect these clouds to hold through the night and will keep temps warmer then they otherwise would be. Stumpf (Issued 130 PM CST Mon Dec 14 2020) Tonight through Tuesday night: High pressure will continue to settle southeast into the area heading into tonight. Lows tonight should end up in the teens and upper single digits, though with the high overhead, a few of the usual cool spots might end up several degrees cooler, especially if they have a deeper snowpack. Mid and high level clouds will remain in place tomorrow morning as high pressure starts to push east of the area.
347 PM CST Mon Dec 14 2020 A high pressure ridge and a fair amount of cloud cover have controlled much of the weather conditions we've seen today across the forecast area.
Cigs should begin to slowly lift through the afternoon ahead of the next approaching cold front. The next cold front will approach tomorrow night and likely bring SHRA to most terminals by 6z.
Lingering showers will follow the exiting upper level trough out of Utah late tonight.
Low temperatures will be in the lower 30s area- wide. In the upper levels, SW flow will begin to develop early Tuesday morning as a deep upper trough crosses the Rockies and begins to move through the Plains. The cloud cover across the region will limit warming on Tuesday with highs expected to range from the low 40s in the NW to low 50s in the SE.
1235 AM EST Tue Dec 15 2020 High pressure and a dry but cool airmass will remain in place across the region through Tuesday.
1049 PM EST Mon Dec 14 2020 A decaying cold front is decaying as it tries to slide southeast towards our area. A line of showers associated with this front attempted to move into the distant Gulf waters and quickly dissipated before reaching the Lower Keys. Temperatures are slowly and steadily falling into the lower 70s with dew points holding near 70. With light winds plus a dew point depression this low, we're keeping an eye on potential fog development. By late Tuesday/early Wedesday, models are locking on to a developing low pressure system off the GA/FL coastline.
High pressure is building in from the north, with colder, drier air advecting into the mid state, but the boundary layer moisture has been reluctant to depart from us. But nearly all of it is concentrated in the lowest 3 kft or so.
Currently weak surface ridging covers Iowa with light northeast to east winds. Meanwhile a weak mid- level trough is slowly moving through the High Plains over western Nebraska/Kansas, spreading light rain and snow in that area. However, as this feature approaches Iowa later today and tonight it will be shunted to our south, moving across southern Kansas and Missouri, with the northern extent of any light precipitation further eroded by dry air entrainment from the aforementioned ridge entrenched over our region.
1015 PM MST Mon Dec 14 2020 The upper trough axis extended from northern WY to northern AZ. A stationary front was located from western MT to central NE with modest pressure falls across CO/NM ahead of approaching trough. Although the pattern is generally more active compared to the last few weeks, quick moving upper level troughs, with a limited moisture tap, will produce little or minimal snowfall amounts for the eastern plains and most of the high valley locations west of the I-25 corridor.
206 AM CST Tue Dec 15 2020 Clouds continue to overspread the region early this morning with an approaching trough to our west. For tonight, flurries will taper off from west to east with the passing of the trough.
With low- level moisture still in place along with layer-lifting in the wake of the cold front, the low-level stratus cloud deck will remain primarily over southeast MS and southwest AL through tonight, while south central AL and the western FL Panhandle could see the low clouds gradually erode from east to west. The hourly temperature trend has remained on track so far this evening, so still anticipate lows tonight to be in the low to upper 30s northwest of I-65 and upper 30s to low 40s southeast. At the surface, ridging builds into the region from the north through Tuesday. The low-level stratus cloud deck will remain over southeast MS and southwest AL throughout the day and overnight, while the low clouds gradually increase once again over south central AL and the western FL Panhandle.
1048 PM MST Mon Dec 14 2020 Winter weather continues over the western slope this afternoon as a trough moves through the central Rockies. The axis of the trough remains just to our west as of 2pm, and this feature will swing through western Colorado this evening and pass east of the Continental Divide by midnight. Forecast precipitation remains on track, with a coating to a half an inch or so in the valleys through tonight, and 2-5 inches in the higher terrain.
In the wake of this departing low pressure system, conditions will begin to dry out under H500 northwesterly flow.
1005 PM CST Mon Dec 14 2020 Early this afternoon Canadian high pressure was building into northern Minnesota, poised to cross the Upper Mississippi Valley tonight and then depart over the Great Lakes on Tuesday. These clouds will set the stage for a tricky low temperature forecast as the high settles overhead and winds decouple. The high will drift off to the east on Tuesday with ridging still extending into the forecast area. Slightly warmer conditions are expected starting mid-week.
This will come courtesy of a closed upper level low that will travel across Oklahoma today and into the Ozarks tonight. Highs today will only be in the low to mid 30s falling into the mid teens to mid 20s tonight which would certainly support accumulating snow providing better moisture.
DGS Chattanooga Airport, TN 52 36 47 32 42 / 0 70 90 10 0 Knoxville McGhee Tyson Airport, TN 49 33 44 33 39 / 0 60 90 20 10 Oak Ridge, TN 48 33 44 32 39 / 0 70 90 20 0 Tri Cities Airport, TN 48 30 42 32 38 / 0 50 90 30 10.