Aikyam-Lab/Synoptic-Bench huggingface dataset:
418 AM MST Tue Feb 9 2021 Persistent upper trough sits over the CONUS, as the upper low spins over central Canada. At the surface, high pressure continues to stretch across MT and the Dakotas, resulting in light winds and cold air over the region.
420 AM CST Tue Feb 9 2021 Most recent surface analysis shows weak high pressure over the area, with a bank of clouds rolling through the southern half of MN.
Look for cloudy and mild weather Tuesday and Wednesday with a slight chance for a few light showers Wednesday afternoon over the higher terrain.
Despite the cloud cover, WAA from southwest flow will warm temperatures this afternoon into the low to mid 60s. Otherwise, a seasonal night in store for the Tennessee Valley with overnight lows in the lower 40s. By Wednesday evening, a warm front ahead of a low pressure system coming out of the western Gulf will move northward across the forecast area.
Although we originally felt it would make it into the valley, westerly winds at the ridgetop may yet hold it at bay another night.
525 AM MST Tue Feb 9 2021 Due to wind chills being warmer than expected have canceled the wind chill advisory. Latest upper air analysis continues to show the long wave trough over the CONUS. Moisture advection over Eastern Colorado along the cold front has lead to warming temperatures and fog. Today the cold front will not move much from where it is in Eastern Colorado. Wednesday the cold front may move closer to the CO/KS border than today. This will cause highs to be a few degrees warmer than today. Lows will be a few degrees warmer than tonight due to the moisture advection. The past few days guidance has been warmer than reality in regard to the actual temperatures.
Surface temperatures in northern Stewart could dip below freezing for a few hours after midnight which could allow precipitation to switch to freezing rain long enough for a glaze of ice to form on cold surface like limbs and vehicles. Rain could switch to freezing rain in the far northwest as early as 9 PM. This could drag down some slightly warmer temperatures making surface temperatures warmer than the models are depicting. We will have to continue to monitor the trends to see if impacts from freezing rain will need to be considered further south along the I-40 cooridor. For now, a winter storm watch was issued for Houston, Stewart, and Montgomery counties where the highest potential exists to reach warning criteria (>0.
Farther south, light fog and patchy light freezing drizzle likely to continue. Light freezing fog will diminish through the morning. This will be the beginning of freezing drizzle and light freezing rain over the southern half or two-thirds of OK from Wednesday. For the first six hours of Wednesday, freezing drizzle and the chance for freezing rain will move north from the Red River area.
Stubborn large scale upper low remains in place over Manitoba/Ontario, keeping arctic air well entrenches across the Northern Plains/Upper Midwest. A jet streak rounding the base of this upper low led to a period of increasing BL winds and with daytime mixing gusts 25 to 35 mph were reported at times this afternoon.
/issued 404 AM CST Tue Feb 9 2021/ A broad upper trough is over the northern half of the country with a very cold, arctic airmass in place. The colder air will have a hard time moving westward today resulting in much cooler temperatures across mainly the Permian Basin from the rest of the area.
A front to our north will keep east central FL with warmer than normal temperatures, very moist conditions and light winds tonight through Wed morning. Min temps will stay in the lower 60s. A little cooler in the lower 80s at the coast due to onshore flow.
1202 PM CST Tue Feb 9 2021 For the 09/18Z TAF update, flight conditions remain poor with a dismal outlook on improvement this period as overrunning SW flow interacts with a sfc cold front, keeping mainly IFR vis/cigs across our airspace. /issued 1040 AM CST Tue Feb 9 2021/ An approaching cold front, with overrunning southwest flow, has kept widespread fog and low clouds across the area as anticipated this morning.
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.
1137 AM CST Tue Feb 9 2021 Cloud cover across wrn Nebraska is disrupting the radiational cooling process and sfc temperatures have warmed into the low single digits to around zero. A developing warm front is producing the cloud cover and this front will lift into nrn Nebraska today and tonight.
Precip type over the southern CWA will be freezing drizzle, with light snow expected across the northern CWA. Overall expect a transition from freezing drizzle south to light snow north. freezing drizzle accumulations will be a glaze to 0.
(This evening through Wednesday) A stalled cold front across our southern counties is slowly lifting north as a warm front. Across the Big Country, temperatures will be below freezing Wednesday morning, so freezing drizzle is possible. Although accumulations are forecast to remain very light, even a light glaze of ice on bridges and overpasses may result in hazardous driving conditions.
There is a possibility of freezing drizzle tonight. Fog and low CIGS will likely move back into KLBB and KPVW early Wednesday behind a slow moving cold front along with strong winds just off the deck. /issued 334 AM CST Tue Feb 9 2021/ There is significantly more coverage to the low stratus/fog early this morning behind an advancing shallow arctic air mass. Although, the low stratus/fog may only briefly make it into the southwestern South Plains. An upper trough will be pushing eastward across the southwestern US tomorrow and will pull the seemingly permanent cold front westward through the day. The front is expected to be west of the Texas/New Mexico by tomorrow evening allowing our western zones to enjoy one last day of warm temps before the frigid cold front takes over.
The recent mid-level pattern featuring an eastern Pacific ridge, and downstream trof over the central/eastern CONUS, looks to remain mostly in place through the upcoming weekend.
Look for cloudy and mild weather today and Wednesday with a slight chance for a few light showers Wednesday afternoon over the higher terrain.
This band is the result of some decent convergence happening, even through ridging is trying to build in at the surface from the North. They also show the convergence weakening and shifting south as the ridge builds south through early afternoon.
Latest RAP/NAM-WRF bufkit soundings suggest depth of the low level saturation will increase enough for a freezing drizzle/light snow chance for tonight through early on Wed, for most of SE KS. It doesn't take alot of freezing drizzle to cause all kinds of problems, so have decided to issue a small winter weather advisory for this chance in SE KS through Wed morning.
Kept northern areas a bit cooler today given the expected cloud cover and went a degree or two warmer across the southern locations. Diegan Chattanooga Airport, TN 62 42 64 50 57 / 10 10 10 60 90 Knoxville McGhee Tyson Airport, TN 55 38 61 47 50 / 10 10 10 50 90 Oak Ridge, TN 54 39 60 46 49 / 10 20 20 60 90 Tri Cities Airport, TN 50 35 56 42 48 / 20 20 20 50 90.
In the low-levels, a mostly west- southwest flow continues to gradually advect low-level moisture into the region through Wednesday morning. Additionally, the enhanced low-level moisture (near saturated airmass in the low-levels) across the region with light winds will favor the development of patchy fog early tonight before areas of fog begin developing mainly north of I-10 after midnight. In the low- levels, southwest flow becomes more dominant through the day on Wednesday. Increasing low-level isentropic upglide on the backside of the weak low-level ridge will also occur on Wednesday. Low temps tonight are expected to be in the low to upper 50s north of I-10 with upper 50s to low 60s south. Highs on Wednesday will be mostly in the low 70s across the region.
Highs will reach the lower to mid 80s, feeling like the upper 80s due to the high moisture content in the air.
Temperatures are currently in the upper 30s in the northwest and the low 50s in the south.
Water vapor imagery depicting closed upper low vortex over Manitoba that has majority of the northern third CONUS under broad upper trough. Latest deterministic runs have closed low vortex rotating down toward the US/Canadian border to begin the weekend then swinging eastward across the northern Great Lakes region.
1019 AM MST Tue Feb 9 2021 Persistent upper trough sits over the CONUS, as the upper low spins over central Canada. At the surface, high pressure continues to stretch across MT and the Dakotas, resulting in light winds and cold air over the region.
However, with deep southerly flow and at least some peeks of sunshine (especially locations east of I-65), temperatures should be even warmer today, reaching the low to mid 60s in most locations by this afternoon. Otherwise, a seasonal night in store for the Tennessee Valley with overnight lows in the lower 40s. By Wednesday evening, a warm front ahead of a low pressure system coming out of the western Gulf will move northward across the forecast area.
Temps have just gotten above freezing here at the office, and we'll probably top out in the low 40s. Again, a similar day tomorrow, with patchy/areas of freezing fog overnight across the Panhandles. The extreme southeast could see some freezing drizzle tonight as well, given the increase moisture depth, and that the warm layer aloft will be just above freezing. For areas that don't get out of the low clouds tomorrow, highs can expect to be in the 20s, where areas right on the edge, may touch the 30s, and the southwest again, looks to be 40s to low 50s.
Kept northern areas a bit cooler today given the expected cloud cover and went a degree or two warmer across the southern locations. ABM Chattanooga Airport, TN 62 42 64 50 57 / 10 10 10 60 90 Knoxville McGhee Tyson Airport, TN 55 38 61 47 50 / 10 10 10 50 90 Oak Ridge, TN 54 39 60 46 49 / 10 20 20 60 90 Tri Cities Airport, TN 50 35 56 42 48 / 20 20 20 50 90.
246 PM CST Tue Feb 9 2021 (Issued 246 PM CST Tue Feb 9 2021) Tonight and Wednesday: High pressure remains in control of our weather regime.
300 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.
For 18Z Aviation discussion below Most recent surface analysis shows weak high pressure over the area, with a bank of clouds rolling through the southern half of MN.
314 PM EST Tue Feb 9 2021 Widespread snow will come to an end this afternoon as weak low pressure exits offshore, with a few scattered snow showers possible tonight.
315 PM EST Tue Feb 9 2021 Widespread snow will come to an end this afternoon as weak low pressure exits offshore, with a few scattered snow showers possible tonight.
959 AM CST Tue Feb 9 2021 Temperatures are warmer than 24hr ago at the same time (still well below zero). Life threatening wind chills continue to be the main impact in the short term period, especially along and north of the Highway 200 corridor. The only saving graces will be light winds coupled with any cloud cover, which this morning is across the southern valley where afternoon highs may be able to break into the low single digits ABOVE zero. However breezy west winds will pretty much kill off any perception of warmer temperatures.
Expect highs be in the low 20s to the north and low 30s to the south this afternoon with lows overnight in the teens. This should stay south of us as even with the warm nose temperatures should stay below freezing through the precipitation column. If any freezing ran is present it will be in far southern portions of the region, but no accumulation is expected.
A fair amount of dry air and surface ridging extending eastward will bring mostly clear skies with only some scattered low clouds as lake clouds struggle to move into southeast Michigan. The 12Z APX sounding did show a respectable depth to the low level inversion, ideal for ducting these clouds inland. The low level flow will remain fairly difluent across Se Mi today as sfc ridging expands into the area from the west.
Yet another wet low pressure system will dampen portions of this weekend.
243 PM CST Tue Feb 9 2021 Current surface analysis places low along the northern Manitoba/Ontario border, with ridge from the lee of the Canadian Rockies southeastward through the northern plains into the midwest.
320 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.
Temperatures are warmer than 24hr ago at the same time (still well below zero). Life threatening wind chills continue to be the main impact in the short term period, especially along and north of the Highway 200 corridor. The only saving graces will be light winds coupled with any cloud cover, which this morning is across the southern valley where afternoon highs may be able to break into the low single digits ABOVE zero. However breezy west winds will pretty much kill off any perception of warmer temperatures.
337 PM EST Tue Feb 9 2021 The elongated polar low(s) now extending from northern Ontario into central Canada is forecast to merge into a more consolidated upper low centered over far southern Manitoba by the end of the work week. Upper jet forcing will drive some ascent along the lower portions of the arctic front over the Ohio Valley on Wednesday. While some of the frontal forcing along the elevated portions of the front will advance into srn Mi, dry air in the low levels will support just some mid/high clouds. Lenawee/Monroe Counties may see a few flurries and/or very light snow being closer to the low level forcing.
839 AM PST Tue Feb 9 2021 A series of low pressure systems moving through southwestern California will bring stronger onshore flow with cooling and more clouds, gusty west winds in the mountains and deserts, and chances for precipitation.
Warm advection in advance of the system will begin tonight atop the shallow cold wedge with light freezing rain or drizzle breaking out to the north of the freezing line. If precip develops along/north of I-44, very cold low lvl temps suggest more flurries or light snow than freezing drizzle. Areas of light freezing rain or rain will become more widespread on Wednesday from southeast Oklahoma into west central Arkansas.
Temperature profiles appear supportive of light snow over freezing drizzle, although freezing drizzle can't be completely ruled out.
428 PM CST Tue Feb 9 2021 A rather warm day across the region saw temperatures in the low to mid 70s as the fog eroded through the morning hours.
Another wet low pressure system will dampen portions of this upcoming weekend.
This drops Abilene?Sweetwater into the upper 20s, Brownwood below freezing, San Angelo to Freezing, and areas farther south much cooler as well.
146 PM PST Tue Feb 9 2021 Weak cold front passing through the region today leading to a few showers in the Sierra Nevada and breezy conditions in the Mojave Desert. A weak cold front passing through the region has provided the San Joaquin Valley and adjacent foothills with ample cloud cover, with a few showers occuring in the Sierra Nevada.
642 PM EST Tue Feb 9 2021 Weak low pressure along the coast will lift northward on Wednesday and bring increased chances of rain, especially to the eastern Midlands. More significant rain is expected late in the week as a series of low pressure systems move northeast along a stalled frontal boundary. After a warm day today where temperatures reached the lower 70s in the CSRA, weak high pressure remains over the forecast area with plenty of low level moisture in place as dewpoints are in the 50s.
The cold front will edge back into the western FA from New Mexico; however, the front will move back into New Mexico this evening into tonight. With much of the area falling below freezing tonight, light icing on elevated surfaces will be possible.
345 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.
631 PM EST Tue Feb 9 2021 Widespread snow will come to an end this afternoon as weak low pressure exits offshore, with a few scattered snow showers possible tonight.
Latest sfc analysis indicates that temperatures are near freezing across the far northwest. 05" Therefore, I slightly expanded the freezing rain chance area to include more of Montgomery and Houston counties. Still looks like sub freezing temperatures will overspread our northwestern areas beginning on Wednesday afternoon or evening.
In addition, scattered shower activity is expected tomorrow, especially by afternoon, amid increasing MSTR/lift as a remnant warm front over the Gulf lifts north through the area. /issued 428 PM CST Tue Feb 9 2021/ A rather warm day across the region saw temperatures in the low to mid 70s as the fog eroded through the morning hours.
Again, models continue to hit the low clouds/dense fog potential pretty hard late this evening and overnight, into Wed morning.
Expect the return of low clouds along with areas of BR and FZFG at the terminal sites early this evening, persisting through at least most of this fcst cycle as the arctic cold frontal boundary remains draped across the region. Temps have just gotten above freezing here at the office, and we'll probably top out in the low 40s. Again, a similar day tomorrow, with patchy/areas of freezing fog overnight across the Panhandles. The extreme southeast could see some freezing drizzle tonight as well, given the increase moisture depth, and that the warm layer aloft will be just above freezing. For areas that don't get out of the low clouds tomorrow, highs can expect to be in the 20s, where areas right on the edge, may touch the 30s, and the southwest again, looks to be 40s to low 50s.
225 PM PST Tue Feb 9 2021 Quiet and mild into tomorrow with a pattern change to unsettled and cooler late week. A short wave trough is about 300 miles off the Coast of Santa Barbara and digging towards the Baja of CA. Clouds will begin to clear some overnight and that will lead to slightly cooler conditions than what we saw last night. Short wave ridging will bring quiet and warm conditions for tomorrow. Bumped highs a bit above the NBM given that info and highs overall should be a few degrees warmer in the Valley tomorrow compared to today and as much as 7 degrees warmer over the mountains given the less cloud cover.
Weak cold front passing through the region today leading to a few showers in the Sierra Nevada and breezy conditions in the Mojave Desert. A weak cold front passing through the region has provided the San Joaquin Valley and adjacent foothills with ample cloud cover, with a few showers occuring in the Sierra Nevada.
Any potential wintry precipitation will be confined to McCurtain county in the form of light freezing rain. Tonight, a gradient of temperatures will exist from lower 30s in our extreme northern zones to low 50s in our southern zones as long as the cold front bisects our region. At this time, we have decided against any winter weather advisories in our northern counties due to higher freezing rain accumulation guidance from the WPC remaining outside of our county warning area.
Current surface analysis places low along the northern Manitoba/Ontario border, with ridge from the lee of the Canadian Rockies southeastward through the northern plains into the midwest.
Widespread freezing drizzle tonight will end by early Wednesday morning at the northeast Oklahoma sites, but will continue through Wednesday elesewhere. Warm advection in advance of the system will begin tonight atop the shallow cold wedge with light freezing rain or drizzle breaking out to the north of the freezing line. If precip develops along/north of I-44, very cold low lvl temps suggest more flurries or light snow than freezing drizzle. Areas of light freezing rain or rain will become more widespread on Wednesday from southeast Oklahoma into west central Arkansas.
This sunshine and the deep southerly flow has helped to warm temperatures into the low to mid 60s across the region as of 21z.
Thin high cloud cover will keep readings just a touch warmer across the south. Boxell (Issued 246 PM CST Tue Feb 9 2021) Tonight and Wednesday: High pressure remains in control of our weather regime.
749 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.
CDG Chattanooga Airport, TN 42 66 49 57 43 / 0 10 40 90 70 Knoxville McGhee Tyson Airport, TN 43 61 44 49 40 / 0 10 40 90 70 Oak Ridge, TN 41 60 42 48 38 / 10 10 60 90 70 Tri Cities Airport, TN 38 56 41 47 39 / 10 20 50 90 80.
Otherwise, the rest of the forecast area will be bisected from northwest to southeast by the arctic cold frontal boundary. Temps to the north and northeast of the boundary across northern sections of the state ranged from the single digits to the upper teens to mid 20s in vicinity of the cold front, and then into the low to mid 30s across southern Wyoming.
143 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.
640 PM EST Tue Feb 9 2021 Widespread snow will come to an end this afternoon as weak low pressure exits offshore, with a few scattered snow showers possible tonight.
At the midlevels troughing is slightly farther north over the Central Plains.
With adequate instability and somewhat favorable wind shear, a strong storm or two may become possible along the warm front Wednesday evening as it lifts north towards the Interstate 20 corridor.
519 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.
Another wet low pressure system will dampen portions of this upcoming weekend. A marine dense fog advisory was needed for inshore waters along NE SC and SE NC coasts, dense in spots due to dewpoints in the lower 60s over frigid SSTs near-shore.
959 PM EST Tue Feb 9 2021 Widespread snow will come to an end this afternoon as weak low pressure exits offshore, with a few scattered snow showers possible tonight.
Not much change to the upper level pattern since yesterday as a large, broad trough remains in place across the CONUS. At the surface, strong high pressure was centered over IA.
This is one reason why the high plains are much drier in winter compared to farther east. Despite higher thicknesses to the southwest, lower cloud ceilings and stronger upslope flow at Elkhart and Johnson will result in daytime temperatures that aren't that much warmer there compared to Hays.
Large upper trough will continue sitting across the CONUS this week.
535 PM CST Tue Feb 9 2021 (This evening through Wednesday) A stalled cold front across our southern counties is slowly lifting north as a warm front. Across the Big Country, temperatures will be below freezing Wednesday morning, so freezing drizzle is possible. Although accumulations are forecast to remain very light, even a light glaze of ice on bridges and overpasses may result in hazardous driving conditions.