Aikyam-Lab/Synoptic-Bench huggingface dataset:
906 PM CST Tue Dec 15 2020 (Issued 905 PM CST Tue Dec 15 2020) The lower clouds that rolled in off the lake as winds turned easterly have pushed inland and lifted. High pressure to our NE combined with a system passing to our south will keep winds easterly.
The low cloud cover along the Missouri River has dissipated, but continues to linger across much of the eastern CWA. Temperatures on Wednesday will turn warmer out west as a milder airmass pushes in from the west.
/Issued 834 PM CST Tue Dec 15 2020/ A wnw-ene oriented light snow band has formed along the deformation zone just north of the track of the upper low as it transitions into an open wave. Some light accumulations have occurred in the Tulsa metro, mainly on grassy and elevated surfaces with temps near freezing and ground temps above freezing.
1049 PM CST Tue Dec 15 2020 A skiff to a few tenths of an inch of snow has been common in areas along and west of I-29 today, but most haven't had any impact from this current upper trough moving through. Wednesday-Wednesday Night: Another progressive upper trough, with limited moisture, will move through the Northern Plains during the second half of Wednesday. Temperatures climb closer to the freezing mark.
Back side of the upper level trough is over the region this evening producing light snow showers. Temperatures have been hovering around freezing which has limited snow accumulations for this event. More clouds streaming in from the northwest should keep temperatures around freezing overnight. Patchy fog combined with wet roads and temperatures near freezing could create slick roads for the Wednesday morning commute.
For today, a low pressure system will pass by to the southeast, working into the Ohio River Valley. Otherwise, expect temperatures today to top out in the upper 20s to lower 30s, though the aforementioned low clouds could keep things slightly cooler than currently expected.
902 PM PST Tue Dec 15 2020 Dry and warmer Wednesday with locally gusty northeast winds near the coastal slopes of the mountains.
High pressure will be in place today, leading to mostly sunny skies and a few degrees of warming. Another ridge of high pressure will build into the region over the weekend providing dry and tranquil conditions.
A cool, dry airmass will result in chilly overnight temperatures the next few days with many outlying communities near the freezing mark this morning.
Rain along the cold front has reduced visibilities. /issued 323 PM CST Tue Dec 15 2020/ A cold front is expected to move through overnight tonight and into Wednesday morning.
1235 AM EST Wed Dec 16 2020 IFR/LIFR stratus is already starting to develop around the Tampa Bay, and is expected to continue to develop and expand south as a cold front approaches from the northwest. /issued 607 PM EST Tue Dec 15 2020/ A deep longwave trough with an embedded short wave progressing eastward will lower surface pressures in the Eastern Gulf overnight. The highest CAPEs will be just offshore and skimming the coast.
A wintry mix will continue through mid morning as the longwave trough pivots through the region. No impacts are currently expected as temperatures will continue to remain above freezing areawide. After sundown, temperatures will quickly fall below freezing across much of the region. There is some concern that light freezing drizzle could occur, but confidence is too low to add at this time. Expect temperatures to only climb into the low to mid 40s during the day.
The lower clouds should begin to scatter out across eastern Oklahoma TAF sites by late afternoon but will likely persist across northwest Arkansas through tonight.
Today Through Thursday Night Abundant low lvl cloud cover was noted acrs the FA early this mrng, assocd with an upr lvl trof movg thru the region. The aforementioned upr trof wl shift to the E of the area today. The airmass wl begin to sloly moderate starting Thu as the high shifts to the SE and W/SW winds return to AR. Max temps wl range fm the mid 40s to the lower 50s, which is still a bit below normal for mid Dec.
Patchy freezing fog will also be possible just before and after sunrise this morning, but isn't expected to hang around long after sunrise. Patchy freezing valley fog will develop just before sunrise, and may also reduce visibility in isolated areas this morning as well, but will dissipate soon after sunrise.
Clouds finally begin to clear more thoroughly by late evening and into the overnight hours as the expansive low over the E CONUS shifts further northeast into coastal New England, and high pressure begins to work into East Texas. /issued 317 AM CST Wed Dec 16 2020/ Cold front is now through the entire forecast area with increasing CAA in the wake of the low pressure/frontal system.
Further enhancing the isentropic glide, a weak wedge front will continue to slide down the southeastern spine of the Northeastern Georgia Blue Ridge Mnts pushing near freezing temperatures into the higher elevations above 2500 feet. Some freezing rain may accumulate along the higher ridgetops, but should remain below a tenth of an inch as temperatures are struggling to get low enough for minor impacts to develop. Lows Thursday morning in the low to mid 30s will slowly rise up into the 40s to low 50s once the clouds break in the late morning to afternoon. Thiem Fcst period starts benign and ridge dominated with some moderating temps.
Low pressure straddles North Florida, with very little gradient across the Florida Keys. The highly progressive flow will limit the strength of the cold front which will push through on Thursday afternoon/evening.
Wrap-around moisture on the northwest side of the low will offer a continued chance for light precip this morning, mainly in the form of light snow (possibly mixed with sleet a times) over southeast IL. Thinking is that enough low level warm air has nudged into wrn KY and sw IN to keep surface temps above freezing. Most locations should be able to get back to more in the way of sunshine during the day Thursday as a bubble high pressure system builds east into the region.
Calm and warmer weather takes hold today and Thursday with the usual breezy conditions through the Central Highlands.
Ripples in the flow aloft pass to the east and ridging builds into the area again, while mountain showers gradually end. We begin to feel the effects of the next upper level trof approaching from the west.
Other than some passing clouds, not much is expected with the wave due to dry air and little to no lift in the low levels. The upper ridge quickly progresses onto the Plains while a surface cool front lines up along the lee of the Rockies.
The cold front yesterday will continue to impact West Central Texas, for another 24 hours. Tonight, another round of low temperatures below freezing look likely, with very light surface winds.
Patchy freezing valley fog will develop just before sunrise, and may also reduce visibility in isolated areas this morning as well, but will dissipate soon after sunrise.
520 AM CST Wed Dec 16 2020 Fresh snow cover, light winds, and small dewpoint depressions will support patchy freezing fog overnight into this morning across the region. Since temperatures are below freezing, patchy slick roads are likely. Could see additional patchy freezing fog tonight into Thursday morning, mainly across eastern/southeast KS, possibly as far west as I-135.
300 AM MST Wed Dec 16 2020 Current surface analysis shows low pressure over southeast SK, with trough stretching southward across far western ND into the Black Hills area. Temps range from mostly teens to the east of the Black Hills to the lower 30s from parts of northeast WY to far western SD. Winds are currently light from the south to the east of the trough, with increasing westerly winds behind it to the west.
Widespread frost at daybreak is a given with a light SW wind or calm as the core of fresh high pressure settles into SE TX at 1027 mb by 9am on Thursday. This high will drift over the region during the day with a light return flow early and spreading E in the wake of the air mass still 1028mb at midnight tomorrow over MS/AL. Warmer trend will commence with the return flow.
310 AM CST Wed Dec 16 2020 An upper level trough is currently moving east across the area early this morning.
608 AM MST Wed Dec 16 2020 Have cancelled the High Wind Warning for Big Timber. The trough will ramp up lift again over the mountains and west.
Showers over the northern mountains will taper off early this evening as a transient ridge moves over the region ahead of a longwave mid-level trough approaching the West Coast. The trough over the West sweeps over the Great Basin on Thursday causing flow aloft to shift to the southwest. Modest mid-level upward forcing and weak overrunning during the afternoon is expected to bring snow the northeast Utah mountains with a chance for light snow showers, possibly mixed with rain in the lower valleys, across the northern half of the forecast area with slight chances in the mountains of the south.
Due to the warm push of air behind the front, and overall limited moisture, snowfall amounts will be on the low side, or under a half inch. The warm airmass may fail to reach the eastern CWA by peak heating with highs possibly cooler than expected. There is some indication for low stratus, or fog developing later tonight into the morning hours on Thursday, mainly over the higher terrain areas of the Sisseton Hills. Temperatures in northeastern SD could be cooler if the low clouds, and/or fog develops later tonight.
544 AM CST Wed Dec 16 2020 Upper level trough currently centered over St. Lows will be in the low to mid 20s.
A wintry mix will continue through mid morning as the longwave trough pivots through the region. After sundown, temperatures will quickly fall below freezing across much of the region. There is some concern that light freezing drizzle could occur, but confidence is too low to add at this time. Expect temperatures to only climb into the low to mid 40s during the day.
442 AM CST Wed Dec 16 2020 Today and Tonight: early morning water vapor imagery/RAP analysis showed the circulation around a closed low spinning over the mid Mississippi river valley. This is still a very slim chance that a flurry or two may be seen early this morning over our northwest most zones but surface temperatures will remain above freezing and no wintry weather impacts are anticipated. High temperatures will only be in the 40s for all except our southeast most counties that will make it into the lower 50s. /22/ Thursday through next Wednesday: This period will start with cold high pressure moving over the region.
/22/ Today and Tonight: early morning water vapor imagery/RAP analysis showed the circulation around a closed low spinning over the mid Mississippi river valley. This is still a very slim chance that a flurry or two may be seen early this morning over our northwest most zones but surface temperatures will remain above freezing and no wintry weather impacts are anticipated. High temperatures will only be in the 40s for all except our southeast most counties that will make it into the lower 50s. /22/ Thursday through next Wednesday: This period will start with cold high pressure moving over the region.
300 AM PST Wed Dec 16 2020 Dense fog is likely to reform across the San Joaquin Valley this morning as high pressure persists aloft. The ridging pattern over the Central California Interior will support the development of fog this morning as the atmosphere remains stable ahead of the next storm. A ridging pattern returns to Central California by the end of the week as fog will once again become a problem for the San Joaquin Valley. Models do show a weak disturbance ride over the ridge and remain north of Central California.
317 AM CST Wed Dec 16 2020 Cold front is now through the entire forecast area with increasing CAA in the wake of the low pressure/frontal system.
The trough will ramp up lift again over the mountains and west.
Band of light radar returns continues to push east ahead of the trough, though thus far not seeing much precipitation reaching the sfc.
411 AM MST Wed Dec 16 2020 Current surface analysis shows low pressure over southeast SK, with trough stretching southward across far western ND into the Black Hills area. Temps range from mostly teens to the east of the Black Hills to the lower 30s from parts of northeast WY to far western SD. Winds are currently light from the south to the east of the trough, with increasing westerly winds behind it to the west.
Light rain continues to spread across Middle Tennessee this morning per radar imagery as a positive-tilt upper trough approaches from the Plains. As the upper trough axis moves closer the next several hours, light rain is expected to increase in coverage per all model guidance, then gradually end from west to east later this morning and afternoon as the trough axis shifts eastward. Forecast soundings indicate that the CAA on the backside of the trough may cool the low levels enough for rain to mix with some light sleet or snow briefly later this morning in the counties along the Tennessee River just before precip ends. In both areas, no accumulation is expected due to the brief period of potential wintry mix and temperatures remaining well above freezing.
Temperature as of 2 am were mostly in the 20's and 30's at the lower elevations and teens and 20's in the mountains. Warmer today as short wave ridging builds over the area with additional warming on Thursday with ridge axis moving east over New Mexico. Cloud cover will increase Thursday morning in advance of an approaching upper level trof.
SFC winds are NW 10KT, then slack & back tonight as high pressure brings a frosty start with a good freeze areawide. Widespread frost at daybreak is a given with a light SW wind or calm as the core of fresh high pressure settles into SE TX at 1027 mb by 9am on Thursday. This high will drift over the region during the day with a light return flow early and spreading E in the wake of the air mass still 1028mb at midnight tomorrow over MS/AL. Warmer trend will commence with the return flow.
326 AM CST Wed Dec 16 2020 Upper level trough currently centered over St. Lows will be in the low to mid 20s.
320 AM CST Wed Dec 16 2020 Light rain continues to spread across Middle Tennessee this morning per radar imagery as a positive-tilt upper trough approaches from the Plains. As the upper trough axis moves closer the next several hours, light rain is expected to increase in coverage per all model guidance, then gradually end from west to east later this morning and afternoon as the trough axis shifts eastward. Forecast soundings indicate that the CAA on the backside of the trough may cool the low levels enough for rain to mix with some light sleet or snow briefly later this morning in the counties along the Tennessee River just before precip ends. In both areas, no accumulation is expected due to the brief period of potential wintry mix and temperatures remaining well above freezing.
Lows will drop into the 40s across most of the area early this morning before warming up into the mid 60s this afternoon, which is about 10 degrees cooler than what we saw yesterday. Some areas, particularly in Brooks, Jim Hogg, and coastal Kenedy, may touch freezing for an hour or maybe even two.
440 AM CST Wed Dec 16 2020 (This evening through Wednesday) A cold front has brought breezy winds across the region this afternoon. Highs will climb into the low to middle 50s tomorrow.
Upper ridge with build into the state today and Thursday for continued warmer downslope conditions. A Pacific trof moves across the state Thursday night.
A digging Central Plains trough will advance into the Upper Ohio Valley this morning. Mid-level warm air intrusion may still play a role in limiting initial snowfall totals across the southeastern ridges and towards the southern end of the WV Panhandle late this afternoon and early evening as rain mixes in with snow. This is reflected in our snowfall forecast, but warmer air impinging farther north could further limit these amounts. GFS continues to be an outlier towards the low-side, though the 00z EC run presents a lower, far more reasonable QPF/snow map than previous cycles. Confidence is high in 8+ inches for most of the ridges, with over a foot possible in some of the higher elevations.
Temperatures are expected to gradually warm over the next few days as the strong upper level low moves from the southern Plains to the East Coast. Areas without snow cover will be a bit warmer and the edges of the snow cover should begin to melt.
515 AM CST Wed Dec 16 2020 An upper level trough is currently moving east across the area early this morning.
Flurries may linger into Thursday with the cold conditions continuing with highs close to freezing both today and Thursday. Have adjusted the arrival time of the snow given ongoing radar and surface obs and trends in light of a some of the high resolution models including the HRRR and HRW WRF/NSSL. RWIS road pavement temperatures were all well below freezing over northern Indiana and should allow snow to accumulate with slippery roads quickly developing.
With clear skies and westerly winds mixing down warmer air, temperatures have risen nicely across the area and are as much as 20 degrees warmer than yesterday. We will be in between two systems tonight/tomorrow as transitory upper-level ridge moves in.
1109 AM CST Wed Dec 16 2020 Upper level trough currently centered over St. Lows will be in the low to mid 20s.
The clouds will keep temperatures above freezing until after 07-08Z, if not longer. Depending on cloud trends, highs will only reach the lower 40s in valleys on Thursday, with upper 30s atop the Cumberland Plateau/Sand & Lookout Mtn areas). Lows should dip into the lower to middle 20s Thursday morning.
The eve update generally involved some cosmetic adjustments as widespread snow continues in response to an encroaching upper trough which features an impressive coupled jet structure. Patchy freezing drizzle will linger, but ice accumlation greater than a trace is not anticipated in that time frame.
Upper level winds will stay out of the northwest for tonight while at the surface with high pressure in place we should see mainly clear skies throughout the night. This should allow low temperatures to fall back into the 10s through much of our central and western counties and the lower 20s in the east. Thursday an upper level ridge will move through the central plains and the pressure gradient at the surface will start to tighten in the afternoon. With the snowpack across much of the south highs will reach into the lower 40s.
Can't rule out some low stratus/fog development overnight with moisture in the low levels and weak low level winds.
As this frontal system pushes east of the state this evening, High pressure begins building into the the region from the southern plains. Will see the low overcast skies lift and clear out by Thu afternoon/evening. There will be some cooler air filtering into GA from the NW tonight which will push lows tonight down into the 30s and lower 40s. This cooler airmass will only allow Hi temps Thursday to get up into the upper 30s across the NE GA mountains and into the 40s elsewhere.
241 PM CST Wed Dec 16 2020 High pressure ridge at the surface over TX is building eastward behind the exiting storm system. That northwesterly wind will usher in cooler and drier air. As a result, overnight lows will drop to below freezing, ranging from the upper 20s to right around the freezing mark.
/ISSUED 522 AM MST Wed Dec 16 2020/ Ripples in the flow aloft pass to the east and ridging builds into the area again, while mountain showers gradually end. We begin to feel the effects of the next upper level trof approaching from the west.
Ridge of high pressure building into the desert southwest will keep stronger northwest flow aloft in place across the region through the day today, then the flow weakens a bit and becomes more westerly tonight. Look for highs in the upper 20s to upper 30s for the high valleys today, and upper 30s to mid 40s for the plains.
140 PM CST Wed Dec 16 2020 (Issued 140 PM CST Wed Dec 16 2020) Tonight through Thursday night: High pressure the dominating influence this period. Heading into Thursday night the lower level flow becomes more southwest and takes any lake effect precip off more to the northeast of the area.
204 PM CST Wed Dec 16 2020 An upper trough responsible for our the increased winds yesterday is quickly moving eastward and out of Texas. Weak ridging behind this trough will improve our temperatures todays as highs will be mostly in the 50s with a few 60s along the Pecos and Rio Grande rivers. Increasing cloud cover on Thursday will help keep temperatures warmer Thursday night.
Overall expect flurries/drizzle will be possible through the period although may also see some pockets of light freezing drizzle overnight as low temperatures fall into the upper 20s and lower 30s. Lingering trace precip will be a challenge Thu evening, with a weak upper wave, cyclonic curvature in the low-level flow, and still plenty of trapped moisture below 850mb. Forecast soundings are only saturated up to about -8C, which leaves the door open for some light freezing drizzle.
Highs will be in the lower 60s. (Thursday night through next Wednesday) Gusty south winds are expected to develop across the Big Country Thursday night as a low-level jet develops, out ahead of an upper trough moving into the central Rockies and Four Corners area.
The Florida Keys remain well upstream of an advancing cold front that will push through the Florida Keys Thursday afternoon and evening. Thereafter, a cold front will slide through the coastal waters from west to east Thursday afternoon and evening.
245 PM EST Wed Dec 16 2020 Low pressure over eastern North Carolina will track northward into southeast Virginia and lift up the Mid Atlantic coast through tonight. Cold and dry high pressure will dominate for the remainder of the week. Temps continue their slow climb over the far NW, currently sitting near or just above freezing. The lack of a feed of drier surface air into the area to provide continued evaporative cooling to compensate for the latent heat release will limit any additional accrual, despite some areas still sitting at freezing. The low level stability and residual moisture with weak surface flow tonight will facilitate fog and stratus development, particularly over the W and S portions of the CWA with weakest low level winds and longer residence time within drier air aloft.
Warm front has made it north into Marion county but surface based instability is still weak. Clearing and colder for Thursday as high pressure builds in from the west.
Therefore the low water advisory will be allowed to expire this afternoon.
251 PM EST Wed Dec 16 2020 Winds continue to veer south to southwesterly today ahead of an approaching cold front. Temperatures today are above normal for this time of year in the low to mid 80s. A low pressure system working across the southeast and up the eastern seaboard into the Mid-Atlantic, which will bring wintry weather to the north. For us down here the cold front draped to the south of this low pressure system will slowly move through our area Thursday. The front will eventually clear through the region with cooler and drier air behind the front. Temperatures will be on a moderating trend as a ridge of high pressure moves off towards the eastern CONUS.
an upper level ridge axis will move over the area ahead of an approaching upper trough.
Models suggesting some erosion of the cloud deck overnight, but may be delayed in doing so as upper troughing pattern broadens and lingers without any true ridging taking place in the short-term.
The cold front will move across the region later this evening and overnight with a few lingering showers possible south of Interstate 4. Drier air will be filtering in during Thursday as high pressure builds in so we should see the clouds erode from north to south during the afternoon hours.