Aikyam-Lab/Synoptic-Bench huggingface dataset:
820 PM CST Tue Feb 9 2021 A weather disturbance will arrive Wednesday, bringing a good chance of light snowfall to much of central Illinois, and possibly some freezing rain south of I-70.
Temperatures are expected to be above freezing so fortunately freezing fog is not expected to be a problem. Thur AM will likely be yet another round of light wintry wx across the PB as minor a shrtwv trof moves atop saturated low-level isentropic ascent between 06Z-18Z Thur. MSLP pressure could increase to around 1038mb at MAF Sun (although strong it is not close to the 1044mb (at MAF) on Jan 10, 1962 when what is considered by some to be the "Greatest Anti-Cyclone of North America" covered most of the CONUS). Winds are not as strong as yesterday, but still sufficient in tandem with the low RH's, so the fire weather threat today remains critical with the Red Flag Warning continuing the rest of the afternoon.
923 PM PST Tue Feb 9 2021 A weak ridge of high pressure will bring a bit of warming for the middle of the week. This will be followed by a parade of low pressure systems moving through southwestern California, which will bring stronger onshore flow with cooler weather, gusty west winds in the mountains and deserts, and chances for precipitation.
253 AM CST Wed Feb 10 2021 Lower condensation pressure deficits and isentropic lift in the 280- 290K layer will continue to support freezing drizzle/light snow over far southeast Kansas and especially for southern Missouri.
General VFR conditions are expected to drop to IFR/LIFR overnight as a warm front moves onshore overnight into Wednesday morning and stalls north of the I-10 corridor Wednesday morning. Fog and drizzle/rain will contribute to the low CIGs Wednesday morning, but will counter balance the reduced VISBYs in the heavier showers. Upper flow remains zonal over the Southeast, on the north side of upper level high pressure stretching west over the Caribbean and Gulf of Mexico. Temperatures remain above seasonal norms through the Near Term due to subsidence from the upper ridge. Low temperatures in the 50s expected tonight and Wednesday night, and high temperatures in the low to mid 70s expected Wednesday.
254 AM CST Wed Feb 10 2021 Freezing drizzle continued overnight across most of southern Missouri causing additional impacts on roadways. Freezing drizzle and freezing rain are expected to increase in intensity a bit this morning over southern Missouri likely impacting the morning commute. Intermittent light freezing drizzle and maybe some flurries are expected on occasion further north into southeast Kansas and areas north of the Interstate 44 corridor.
835 PM MST Tue Feb 9 2021 Expanded and increased PoPs and QPF slightly, especially northward, for Wednesday morning into afternoon as another reinforcing cold front and upper disturbance bring an expansion of light snow.
(Today and tonight) Early this morning, a cold front has made its way through the forecast area, with widespread cloud cover and patchy fog/freezing fog having developed. Isentropic lift is starting to kick in, resulting in patchy drizzle (and patchy freezing drizzle in the Big Country, northern Concho Valley, and northern Heartland where temperatures are at or below freezing). With freezing temperatures at the surface spreading further south across the rest of the Concho Valley and Heartland, a mix of light freezing rain/sleet/rain will be possible there, in addition to areas to the north. Meanwhile, for most of the I-10 corridor, temperatures may stay just above freezing, resulting in regular rain and also perhaps a thunderstorm or two due to CAPE values above 500 J/KG.
Where sea-surface temperatures north of the Keys are in the upper 60s or cooler, some sea fog development is possible overnight. Indeed, the sounding observed a 500 mb height of 5880 meters, highlighting the strong mid-level high pressure over South Florida and the Keys this evening.
952 PM CST Tue Feb 9 2021 Unamplified west-southwesterly flow aloft will prevail across the TN Valley region overnight, as the leading edge of an arctic airmass crawls very slowly southeastward in the lower-levels. If anything, temperatures could end up being a few degrees cooler to the south and east of the frontal wind shift axis, where a lower coverage of clouds and lighter winds will support decent radiational cooling. We have lowered temps in this region into the lower 40s to reflect the reasoning noted above, and subsequently introduced patchy fog for many areas.
1058 PM EST Tue Feb 9 2021 A deep upper low will remain in place across south central Canada through the upcoming weekend, with disturbances aloft rotating through the base of the trough every 24 to 36 hours.
(Today and tonight) Freezing drizzle is ongoing and will likely continue much of the day over central and southern Oklahoma where lift over the front is stronger. With the approach of the upper wave from the west, freezing rain is also expected in south central and southeastern Oklahoma.
1240 AM EST Wed Feb 10 2021 Widespread snow will come to an end this afternoon as weak low pressure exits offshore, with a few scattered snow showers possible tonight.
Upper flow remains zonal over the Southeast, on the north side of upper level high pressure stretching west over the Caribbean and Gulf of Mexico. Temperatures remain above seasonal norms through the Near Term due to subsidence from the upper ridge. Low temperatures in the 50s expected tonight and Wednesday night, and high temperatures in the low to mid 70s expected Wednesday.
157 AM MST Wed Feb 10 2021 Upper low remains parked over Manitoba/Ontario, keeping a cold airmass over the northern tier of the CONUS. With cold high pressure over the Dakotas, winds are generally northerly 5-10 mph.
1224 AM EST Wed Feb 10 2021 A deep upper low will remain in place across south central Canada through the upcoming weekend, with disturbances aloft rotating through the base of the trough every 24 to 36 hours.
Unamplified west-southwesterly flow aloft will prevail across the TN Valley region overnight, as the leading edge of an arctic airmass crawls very slowly southeastward in the lower-levels. If anything, temperatures could end up being a few degrees cooler to the south and east of the frontal wind shift axis, where a lower coverage of clouds and lighter winds will support decent radiational cooling. We have lowered temps in this region into the lower 40s to reflect the reasoning noted above, and subsequently introduced patchy fog for many areas.
1116 PM CST Tue Feb 9 2021 A weather disturbance will arrive Wednesday, bringing a good chance of light snowfall to much of central Illinois, and possibly some freezing rain south of I-70.
It captures the persistence of above freezing surface conditions in the HOP vicinity, too. Similarly, with the warmer temps in the southeast lingering, most of the day, certainly impact wise, will be mostly liquid rain for the HOP area. As a result, we left the northwest row of counties as a buffer zone, with the combo of light snow/sleet and freezing pcpn validating its continued warning.
With this in mind, have cancelled the High Wind Warning and opted for a Special Weather Statement in its place for the I-80 corridor, Arlington and Elk Mountain, between Laramie and Rawlins. Already have seen temperatures in Cheyenne drop from the mid 40s to the low 30s in the span of 30 minutes as the front wiggles around as it drapes itself across the region.
533 AM CST Wed Feb 10 2021 Cold front accompanied by low clouds and fog producing LIFR cigs at MAF and HOB. Fog and freezing fog is developing across the Permian Basin and Lea County so a Freezing Fog Advisory has been issued through this morning. Patchy drizzle and freezing drizzle is also possible through the day with highs ranging from the upper 20s across the northern Permian Basin to the lower 80s along the Big Bend. The cold air will continue moving through the area tonight with patchy drizzle and freezing drizzle possible. Freezing rain and sleet will also be possible across northern areas.
A subtle warm front then lifts northward across Alabama during the early morning Thursday. If the warm front lifts farther north, then rainfall totals may also increase. Cold front pushes through late Thursday, which will end the rain from northwest to southeast.
429 AM EST Wed Feb 10 2021 Dry weather continues today and Thursday with high pressure building in. Temperatures will remain colder than normal and mainly below freezing over the next several days.
While pops are rather high, and could be even higher, QPF amounts will be on the low side.
Temps may slip toward freezing in parts of the far north, but no major ice impacts are expected this morning. Across our northwest counties, forecast thermal profiles clearly show development of a sub-freezing layer at the surface with a pronounced warm nose overhead. This means rain changing to freezing rain, rather than snow. Amounts look lighter and more uncertain farther south and east with impacts primarily being slick spots on bridges and overpasses. For Nashville, just a very thin glaze is expected if temps do drop to freezing.
Canadian high pressure is north of the boundary and centered over Iowa.
259 AM PST Wed Feb 10 2021 Quiet and mild today with a pattern change to unsettled and cooler late week.
Clouds will increase Thursday afternoon as a short wave trough approaches from the Northern Plains.
This will help apparent temps feel warmer and most likely climb out of the warning criteria, less than 40 below, for a short duration late this afternoon into the early evening. The traditionally cold spots should fall into the minus 30s given the lighter winds and their recent trends to beat the lower guidance.
521 AM CST Wed Feb 10 2021 Lower condensation pressure deficits and isentropic lift in the 280- 290K layer will continue to support freezing drizzle/light snow over far southeast Kansas and especially for southern Missouri.
Arctic high pressure continues to build over the area as it slides down the front slopes of the Canadian and Northern Rockies.
Latest obs show the visibilities improving with the lowest visibilities now from southeast Colorado into the Texas Panhandle. Thursday should be a little warmer again with highs in the teens and 20s.
another piece of energy rotates around closed upper level low over central Canada and moves across the forecast area Thursday/Thursday evening.
The stretch of very cold temperatures continues today as arctic high pressure continues to push into the area. Temperatures are a little warmer across the southern parts of the plains, where some mid and upper level clouds have prevented the efficient radiation seen further to the north. South of the stationary front that remains hung up on the mountains, temperatures will be quite a bit warmer, with some areas in the far southwest getting into the mid to upper 20s.
At this time extent of 1/4 mile visibility, deposition from fog, and freezing drizzle are not expected to be widespread enough to warrant any sort of advisory; however, will continue to monitor as the night progresses. Will make little change to the fog/drizzle/freezing rain forecast at this time. The trough train will continue through much of the forecast period. Some light wintry mix precip may be possible across the southeastern Rolling Plains tomorrow morning and early afternoon as an upper level trough moves across northern Mexico.
425 AM MST Wed Feb 10 2021 Upper low remains parked over Manitoba/Ontario, keeping a cold airmass over the northern tier of the CONUS. With cold high pressure over the Dakotas, winds are generally northerly 5-10 mph.
As previously mentioned, snowfall accumulations (especially over the northern Colorado mountains) appear to be the low end of earlier forecasts. Relatively dry air doesn't arrive in earnest until late afternoon / evening when the trough axis finally pushes through our CWA. Another system sits on the doorstep as a trough moves toward the Pacific Northwest coast on Thursday.
There is potential for wintry precipitation later this weekend as low pressure develops near the East Coast.
Fog and freezing fog is developing across the Permian Basin and Lea County so a Freezing Fog Advisory has been issued through this morning. Patchy drizzle and freezing drizzle is also possible through the day with highs ranging from the upper 20s across the northern Permian Basin to the lower 80s along the Big Bend. The cold air will continue moving through the area tonight with patchy drizzle and freezing drizzle possible. Freezing rain and sleet will also be possible across northern areas.
A weak trough axis will then move southeast across Lake Ontario to night. The band of snow should intensify as convergence increases along the trough axis, with a band of heavy snow moving south across Oswego County and back towards far northern Cayuga County. Snow showers will continue across the higher terrain east of the lake through this morning. A few spots may see 1- 3 inches across the higher terrain from the Boston Hills southward along the Chautauqua Ridge.
Overnight lows will again be 10 to 15 degrees above normal with lows in the low to mid 50s. Given the high temperatures and dew points near 60 afternoon SBCAPE climb up to 1000J/Kg with some decent surface sheer. The lower level lapse rates are limited by a warm nose as forecast soundings show and given the systems parallel traverse to the upper level flow, lifting mechanisms will be locally isolated.
High pressure returns on Thursday with temperatures warming to above normal.
High pressure nosing in from the north will keep daytime highs below normal. Low pressure will develop this evening off the Georgia coast, moving northeastward through the offshore waters of the Carolinas overnight. A pulse of 300K isentropic lift should develop ahead of this low, producing a wave of showers within the shallow moisture that extends only up through about 10k feet (~700 mb). Highs should range from the upper 50s across Bennettsville and Lumberton to the lower 60s elsewhere. High pressure remains wedged in from the north Thursday night.
It captures the persistence of above freezing surface conditions in the HOP vicinity, too. Similarly, with the warmer temps in the southeast lingering, most of the day, certainly impact wise, will be mostly liquid rain for the HOP area. As a result, we left the northwest row of counties as a buffer zone, with the combo of light snow/sleet and freezing pcpn validating its continued warning. And for our far southeast (HOP area), this higher impact will be overnight into early Thursday morning.
349 AM PST Wed Feb 10 2021 A deeper marine layer will keep the coast and valleys cooler today with warming for Thursday as high pressure moves across California.
557 AM CST Wed Feb 10 2021 (Today and tonight) Freezing drizzle is ongoing and will likely continue much of the day over central and southern Oklahoma where lift over the front is stronger. With the approach of the upper wave from the west, freezing rain is also expected in south central and southeastern Oklahoma.
533 AM CST Wed Feb 10 2021 (Today and tonight) Early this morning, a cold front has made its way through the forecast area, with widespread cloud cover and patchy fog/freezing fog having developed. Isentropic lift is starting to kick in, resulting in patchy drizzle (and patchy freezing drizzle in the Big Country, northern Concho Valley, and northern Heartland where temperatures are at or below freezing). With freezing temperatures at the surface spreading further south across the rest of the Concho Valley and Heartland, a mix of light freezing rain/sleet/rain will be possible there, in addition to areas to the north. Meanwhile, for most of the I-10 corridor, temperatures may stay just above freezing, resulting in regular rain and also perhaps a thunderstorm or two due to CAPE values above 500 J/KG.
The frontal boundary over the Gulf will move north as a warm front with scattered showers developing along with a continuation of MVFR type ceilings through the afternoon. Canadian high pressure is north of the boundary and centered over Iowa.
They will get a bit more lift from an inverted trough stretching off a weak CO low. Mid to high level moisture will be ample as an upper trough digs in.
Showers currently developing along the warm front should continue to lift north through the day with a few thunderstorms possible. Otherwise vfr to LIFR to continue at the TAF locations through tomorrow until the cold front passes. The frontal boundary over the Gulf will move north as a warm front with scattered showers developing along with a continuation of MVFR type ceilings through the afternoon. Canadian high pressure is north of the boundary and centered over Iowa.
Warm temps reaching the low to mid 80s may approach record highs at LEE/SFB/MCO. Overnight lows in the low-mid 60s.
A cold front pushing through will keep low clouds across the region for the entire TAF period. Fog and freezing fog is developing across the Permian Basin and Lea County so a Freezing Fog Advisory has been issued through this morning. Patchy drizzle and freezing drizzle is also possible through the day with highs ranging from the upper 20s across the northern Permian Basin to the lower 80s along the Big Bend. The cold air will continue moving through the area tonight with patchy drizzle and freezing drizzle possible. Freezing rain and sleet will also be possible across northern areas.
Diegan Chattanooga Airport, TN 48 54 41 51 42 / 70 90 40 20 60 Knoxville McGhee Tyson Airport, TN 44 48 38 47 40 / 60 90 50 10 50 Oak Ridge, TN 41 48 36 47 39 / 70 90 40 10 40 Tri Cities Airport, TN 40 46 38 47 38 / 30 90 70 10 40.
Soundings show a sub-freezing layer at the surface with a pronounced warm nose overhead. This will indicate freezing rain over the area, rather than snow. Amounts look lighter and more uncertain farther south and east with impacts primarily being slick spots on bridges and overpasses.
105 PM EST Wed Feb 10 2021 A low pressure system will move from the Gulf coast region toward the Carolinas over the next couple of days.
Latest models still support the warmer scenario but not as strongly as they did yesterday.
This pushed snowfall totals into the high end advisory (4-6/3-5") range from the Laurel Highlands eastward along the southern tier/MD line into parts of the lower Susq. The highest confidence for an upgrade to winter storm warning would be Somerset County. Snow should taper off from NNW to SSE during the predawn and early morning hours Thursday as drier northerly flow and sfc ridging arrives in wake of the departing system.
Meanwhile, Pulaski is currently sitting in the low 70s! The focus of the forecast continues to be overnight and tomorrow as shower activity becomes more widespread this evening along and north of I- 40. Surface temperatures will drop below freezing as soon as 03z in the farthest northwest locations and the freezing line will sag southward through the overnight and early morning hours. The greatest threat continues to be in the northwest where temperatures will be below freezing the longest. The greater uncertainty is how much QPF falls during the below freezing window. Second, the warm nose will be 4-6 degrees C above freezing, so a lot of latent heat will have to be released for accretion. I did move the start time to the advisory to 9 PM due to temperatures staying safely above freezing until then.
mostly in the form of freezing drizzle, with some light snow at times continues across much of eastern Oklahoma and northwest Arkansas.
This moisture will begin to surge back northward as the front lifts northward as a warm front overnight ahead of an incoming system. On Thursday morning, showers and embedded thunderstorms will be ongoing ahead of the incoming cold front across northern Alabama and the Tennessee Valley.
/issued 533 AM CST Wed Feb 10 2021/ Cold front accompanied by low clouds and fog producing LIFR cigs at MAF and HOB. Fog and freezing fog is developing across the Permian Basin and Lea County so a Freezing Fog Advisory has been issued through this morning. Patchy drizzle and freezing drizzle is also possible through the day with highs ranging from the upper 20s across the northern Permian Basin to the lower 80s along the Big Bend. The cold air will continue moving through the area tonight with patchy drizzle and freezing drizzle possible. Freezing rain and sleet will also be possible across northern areas.
The cold front from temperatures and winds appeared to be be from near Nashville to just NW of far NW AL, to Jackson MS. A subtle warm front then lifts northward across Alabama during the early morning Thursday. If the warm front lifts farther north, then rainfall totals may also increase. Cold front pushes through late Thursday, which will end the rain from northwest to southeast.
215 PM EST Wed Feb 10 2021 A low pressure system will move from the Gulf coast region toward the Carolinas over the next couple of days.
Min temps again in the low to mid 60s which remains 10-15 degrees above normal. S/SE flow will continue resulting in above normal temperatures, peaking in the low to mid 80s. Rain chances will be a little higher as a slug of moisture is progged to lift north across the area on the western periphery of the Atlc ridge.
1143 AM CST Wed Feb 10 2021 Freezing drizzle continued overnight across most of southern Missouri causing additional impacts on roadways. Freezing drizzle and freezing rain are expected to increase in intensity a bit this morning over southern Missouri likely impacting the morning commute. Intermittent light freezing drizzle and maybe some flurries are expected on occasion further north into southeast Kansas and areas north of the Interstate 44 corridor. For Thursday, some lingering freezing drizzle and flurries are expected early, then clearing up for the afternoon.
1112 AM CST Wed Feb 10 2021 (Today and tonight) Freezing drizzle is ongoing and will likely continue much of the day over central and southern Oklahoma where lift over the front is stronger. With the approach of the upper wave from the west, freezing rain is also expected in south central and southeastern Oklahoma.
1043 AM CST Wed Feb 10 2021 (Today and tonight) Early this morning, a cold front has made its way through the forecast area, with widespread cloud cover and patchy fog/freezing fog having developed. Isentropic lift is starting to kick in, resulting in patchy drizzle (and patchy freezing drizzle in the Big Country, northern Concho Valley, and northern Heartland where temperatures are at or below freezing). With freezing temperatures at the surface spreading further south across the rest of the Concho Valley and Heartland, a mix of light freezing rain/sleet/rain will be possible there, in addition to areas to the north. Meanwhile, for most of the I-10 corridor, temperatures may stay just above freezing, resulting in regular rain and also perhaps a thunderstorm or two due to CAPE values above 500 J/KG.
1132 AM CST Wed Feb 10 2021 Lower condensation pressure deficits and isentropic lift in the 280- 290K layer will continue to support freezing drizzle/light snow over far southeast Kansas and especially for southern Missouri.
A weak ridge will build in on Thursday, bringing slightly warmer temperatures.
Rain chances decrease tonight with the main focus for precip to our northwest ahead of an approaching cold front. Rain chances increase from northwest to southeast across the area on Thursday as the cold front slowly moves into the area.
Temperatures remain above freezing for the entire area, but the northern tip of Stewart has been flirting with the 32 degree line. First, how far south will the freezing temperatures get? Temperatures will need to get to 30 or 31 for decent accretion to occur. Second, where will the QPF align with the frozen temperatures? The higher QPF amounts will be along and south of I-40 where temperatures will likely stay above freezing. Chances for rain during the day, and freezing rain tonight and overnight will impact terminals.
This will allow afternoon temperatures to climb into the low to mid 80s today as weak mid level high pressure spreads over most of the Peninsula from the east and a stationary front stays across northern Florida.