Aikyam-Lab/Synoptic-Bench huggingface dataset:
1033 AM MST Thu Jan 14 2021 Potent upper level trough was moving east into the Northern/Central Plains. Strong cold front accompanied by a band of snow and wind gusts of 60 to 90 mph was moving through Northeast CO. Skies have cleared, except for lingering low/mid clouds over the higher terrain. Winds decreased since the frontal passage, but were gusting 40 to 50 mph across the high plains. Dry conditions are forecast through Friday with cooler than normal temperatures (highs in the 20s and 30s).
Meanwhile, a deepening cyclone across the Central Plains will slowly translate eastward, dragging a cold front across MS and AL. Across the highest elevations of northeast Georgia where surface temperatures will be right at to just above freezing, light snow could mix with the rain between 10z and 14z, but no accumulations or impacts are expected. CAA will commence as the cold front pushes eastward and out of the CWA on Friday afternoon/evening.
Cold front has moved through most of the area early this morning with gusty northwest winds developing behind the front.
SHORT TERM (Tonight through Friday Night): 500mb trough moving eastward across the central United States this afternoon will bring a cold front into the western portions of the CWA late this afternoon into early this evening and through the rest of deep South Texas this evening. Temperatures will be near freezing across the northern ranchlands Fri night/Sat morning but not enough to warrant a freeze watch at this time.
Passing ridge tonight will support fair dry weather. Warmer air ahead of the system will allow the nearly all the precipitation that arrives by afternoon into western New York ahead of the occlusion to fall as rain.
A high-amplitude ridge aloft will continue to translate rapidly eastward across the region late this morning, with mid-level flow expected to back to the southwest and strengthen by late afternoon. Max temperatures are still predicted to range from the lower 50s in the higher elevations of northeast AL/southern TN to the mid 50s in valley locations. As mentioned above, a quick-moving cold front will be moving into the Tennessee Valley this evening and overnight in response to a deepening upper-low over the Northern Plains that will barrel into the Great Lakes and Ohio Valley. A cooler and drier air mass will move in behind the front and quickly put an end to the rain and scour out any remaining cloud cover by the mid-morning on Friday.
Radar shows a fairly stationary plume of return flow around an elongated low pressure system that has been training across north Central MN for the majority of the day. Believe this is in response to a lot of southward momentum generated by strong winds across the Great Plains which have acted to pull the low further southward. Models have been indicating some semblance of this, but prior runs were placing the low way too far to the north; instead, it has trended more towards the stronger forcing to our south. Northwest WI will still fair the best in terms of accumulating snow, but even numbers there have been reduced due again to the more southern track of the low.
1130 AM CST Thu Jan 14 2021 A strong cold front was racing southward across Kansas early this morning with associated surge of wind gusts surpassing 50-60mph for several locations. The high wind warning has been expanded and extended through Friday, as this upper level vortex continues to influence the central plains.
A longwave trough over the north-central Plains today dives southeast towards the Upper Midwest tonight and cuts off from the northern jet stream, forming a deep upper low that then meanders eastward across the Midwest and Great Lakes states through Friday. Beneath this feature, low pressure deepens at the surface and eventually stacks beneath the upper low. A cold front associated with this low dives southeast through the lower Mississippi River Valley and towards the local area late tonight into early Friday morning. There are no concerns for wintry precip as temperature profiles remain well above freezing throughout the sfc-700mb layer, even over our inland areas. Friday will be sunny as skies clear behind the front, but cooler with breezy northwest winds and high temps hovering in the low to mid 50s.
227 PM CST Thu Jan 14 2021 (Issued 226 PM CST Thu Jan 14 2021) Tonight and Friday: There have been some slight changes to the forecast due to warmer temperatures and slower arrival of precipitation. The low pressure trough currently centered over the Mississippi River will deepen and become centered over the Wisconsin/Iowa border during the late afternoon/early evening. As the low strengthens due to cyclogenesis, we'll see an increase in precipitation coverage due to a focus of positive vorticity advection and frontogenesis over our area. With temperatures around or several degrees above freezing precipitation could start out as rain before switching over to a wet slushy snow. After midnight snow will gradually taper off into Friday morning but lingering light snow and drizzle will be possible as low level moisture becomes trapped under the low.
Speedy NW flow aloft will prevail over the High Plains through Friday -- between a pronounced upper level ridge along the Pacific Coast and an amplifying upper level low over the Upper Midwest/Upper MS River Valley. Low-level/mid-level flow will begin to decrease late Friday afternoon as the upper low progresses eastward into the OH Valley and the MSLP /height/ gradient over the High Plains begins to relax. A closed low does develop at the base, moving southward through the central Rockies. The closed low does split from the main trough, hinting at the bulk of precip stays north of the CWA with trough, and west/south of the CWA with the closed system.
The developing stacked low pressure system over the Upper Midwest will consolidate into a very deep vortex over eastern Iowa by tomorrow morning. Although the strong winds of this afternoon will diminish substantially with decoupling around sunset, wind speeds are expected to start increasing again late tonight, particularly in the north, as the surface pressure gradient associated with the low pressure system tightens. The strongest winds may not align temporally with the lowest relative humidities, and this results in the warning extending through the entire day tomorrow.
317 PM EST Thu Jan 14 2021 High pressure over the area this afternoon and evening will bring near normal temperatures for the remainder of today. A strong cold front will cross the area Friday, bringing showers.
1058 AM EST Thu Jan 14 2021 Currently - A ridge extending from the Gulf of Mexico into Flroida is maintaining mostly moderate north to northeast breezes across the Keys. Deep layered moisture also remains high, having been strung behind the departing trough aloft. Short Term Update - The ridge across northern Florida will gradually shift southward into Central Florida through the afternoon, and further into South Florida tonight. With nothing coming along to kick out the low level moisture or cause significant warming, cloudy skies will have a hard time breaking up this afternoon. A ridge extending across northern Florida will shift southwards into Central Florida this afternoon.
It will be windy today for all sites as northwest winds gust to 30+ knots across the area this afternoon behind a cold front that moved through this morning. Cold front has moved through most of the area early this morning with gusty northwest winds developing behind the front.
(This evening through Friday) Fairly strong and gusty north winds have occurred in the wake of cold frontal passage from this morning. A large upper level low will drift east across portions of the Midwest on Friday. This is where surface pressure gradient will be tightened, and where some downward momentum transport is expected as northwest winds become aligned in the lower to mid levels. Despite abundant sunshine, temperatures will be a little cooler across our area.
243 PM CST Thu Jan 14 2021 Other than being a little breezy with a few high clouds streaming in ahead of the cold front it has been a mild afternoon across the area. The cold front will move quickly across the area this evening and overnight, but will remain dry across the inland zones.
Precipitation will begin to spread across the region Friday as a frontal system associated with an approaching midwest upper low begins to impact the region. then changing back all over to snow over the course of the afternoon as cold air moves in behind the cold front.
The storm broke the back of a weather pattern of a semi- permanent ridge over the northern Rockies of late.
/Tonight through Friday Night/ Cold front continues to make steady SE progress across the region this afternoon with gusty NW winds following fropa and continuing through sunset. Thus, expect mostly clear skies overnight with low temperatures falling into the lower to mid 30s as W/NW winds drop off sharply later tonight. In addition, the winds combined with very dry air in place behind the cold front will also result in very low RH values on Friday, generally in the 15-25% range as temperatures gradually warm into the lower to mid 50s by Friday afternoon.
Forecast PW's look to fall into the 10th percentile by this evening, though this is short-lived as PW's steadily increase throughout the day Thursday as winds shift and increase from the S/SW ahead of an approaching cold frontal boundary. This boundary originates from a deepening longwave trough across the eastern CONUS and a cutoff low near the Great Lakes region.
1053 AM EST Thu Jan 14 2021 Areas of freezing fog across far northwest Georgia will continue to erode over the next hour or so as insolation increases and temperatures increase in response. Have massaged temperatures a bit in the near term, but highs are still on track to reach the lower to mid-50s across the northern CWA and upper 50s to around 60 farther south, under a sunny to mostly sunny sky. Have issued freezing fog advisory for 2 counties and a special weather statement for several other far north and NW counties. By tonight, SW flow aloft on the periphery of the large upper low increases upward motion from DPVA and low level warm advection. Temps should remain above freezing for the duration of the event tonight and Friday, even at the highest elevations.
205 PM CST Thu Jan 14 2021 Upper trough swinging across the plains today will develop into a closed low as it moves into the Mississippi River Valley.
950 AM MST Thu Jan 14 2021 Potent high wind event will continue through today as strong low pressure traverses the region. Secondary impulse will push into the region tonight, supporting sustained strong ll flow and good mixing as the upper trough deepens to the east.
The wind is being caused by the fairly strong surface pressure gradient between the strong upper level low situated across Illinois that helped drag the front through South Central Texas this afternoon and high pressure situated to our west. While winds should decrease through the over night hours the large surface and upper trough will be slow to move eastward tomorrow resulting in another windy afternoon as high pressure tries to nudge in from the west. Highs on Friday under sunny skies will be cooler than today by about 7-10 degrees, back to near or just below normal.
North winds behind the cold front have increased to advisory levels across these areas, and will continue into this afternoon. (Today and tonight) An upper level trough is moving east across the northern and central plains this morning, with a strong cold front driving south through southwestern Kansas and into the northern Texas Panhandle area. This cold front will move into our northern counties between 6 and 8 AM this morning, likely making it to the I-10 corridor before Noon.
1256 PM CST Thu Jan 14 2021 A low pressure system moves south over the Rockies and into the upper MS River valley early Friday. The low continues to push east over the Great Lakes and into Canada.
1136 AM MST Thu Jan 14 2021 A potent trough continues surging southeastward through the central Rockies and high plains early this morning. Strong winds have persisted overnight in the higher terrain behind a cold front. Eventually later today, strong jet stream winds will gradually move eastward as the overall trough shifts toward the midwest. An isolated snow shower or two can not be ruled out in the central mountains this morning, however that will be about is as any lingering moisture with this trough has shifted well east of Colorado.
109 PM EST Thu Jan 14 2021 Strong cold front Friday with lower elevation rain and higher elevation snow.
1259 PM EST Thu Jan 14 2021 High pressure over the area will bring near normal temperatures this afternoon. A strong cold front will cross the area Friday, bringing showers.
158 PM CST Thu Jan 14 2021 A light shower will be possible across a portion of the eastern area before midnight mainly near Meridian location due to some return moisture from an upper level trough swinging through. The previous mentioned upper trough will swing across the plains and continue to progress east Friday, dragging a dry/cold front through the region. As this cold front pushes through, there will be a tight pressure gradient which is a good indicator that there will be some high winds at the surface. On top of winds, temperatures will be cooler tomorrow with some places in the north only reaching the upper 40s while elsewhere will be in the lower 50s.
242 PM CST Thu Jan 14 2021 A cold front will bring rain to central Illinois this evening, then mix with or change to snow late this evening and overnight. Over the next couple days, expect highs in the low to mid 30s and overnight lows in the upper 20s to around 30. This afternoon, a cold front is passing across the Illinois River Valley into central Illinois with accompanying rain a breezy west winds. Initially rain, falling temps behind the cold front will allow precip to mix with or transition over to snow late this evening and overnight, especially north of I-72. Once precip associated with the cold front moves through this evening, expect a several hour lull in precip across central Illinois.
Cooler today under dry northwest flow aloft ahead of the next Pacific ridge that will pass through our area Friday.
A low pressure system tracking to the south will bring a prolonged period of wintry mix to the region starting this afternoon and continuing through at least Friday. The onset of the precipitation is once again delayed due to dry air in place in the low levels of the atmosphere. The initial dry low levels could lead to some rain and freezing rain this afternoon and this evening. Later tonight into Friday, some mid level dry air could hamper ice crystal formation with freezing rain or drizzle again a possibility. It appears the mesoscale models are keying in on central and east-central Wisconsin for the highest snowfall totals this run, mainly tonight, as mid level frontogenesis combines with the best moisture for several inches of snowfall across this area.
An area of high pressure has moved over the FL peninsula, and with dry air moving in, low clouds cleared. Winds will become light and variable as the high crosses the peninsula tonight, providing for an opportunity for temps to drop to the 40s. On Fri morning, a strong low pressure system will be moving over north central U. with a cold front extending from it towards southeast U. Highs on Fri will reach the lower 70s.
A weak cold front will cross the area between 19-23z with winds shifting to the NW and becoming briefly gusty. High pressure over West Texas will will bring a N-NW flow to area TAF sites and clear skies.
300 PM EST Thu Jan 14 2021 A strong cold front will cross North Carolina Friday and Friday night, bringing showers on Friday and colder weather for the weekend. The high will move southeast over the Atlantic Ocean while the low will remain nearly stationary over the Midwest. Even as the low remains stationary, the associated cold front will move from the Mississippi River to the spine of the Appalachian Mountains overnight. Although winds will remain out of the south around 5 mph tonight, limiting true radiational cooling potential, the clear skies at the beginning of the night will allow temperatures to drop cooler than last night by 3-7 degrees. The low pressure system will slide south Friday, with the cold front sliding across North Carolina during the day and reaching the I-95 corridor by evening.
This represents our next weather maker as an associated cold front is expected to move our way and push across our area late tonight. A vigorous and rather deep upper level low will be moving across the Indiana area. Curvature and shear will amplify toward the southwestern side of the low.
Main purpose for the morning update was to remove the wording for the freezing fog advisory since it was allowed to expire at 10am. Still had a few spots that were sitting right at the freezing mark at 10am, while also showing dense fog. Morning runs of the HRRR and other high res guidance showed ever so slightly cooler temperatures in those areas. Will update the ZFP and HWO to remove freezing fog wording and that should do it for the morning update. CD Chattanooga Airport, TN 37 50 31 41 30 / 30 20 10 10 10 Knoxville McGhee Tyson Airport, TN 37 47 30 38 30 / 30 30 10 20 10 Oak Ridge, TN 36 47 30 38 29 / 30 30 20 20 10 Tri Cities Airport, TN 31 44 28 36 27 / 40 50 10 50 20.
943 AM PST Thu Jan 14 2021 Thursday will feature a good deal of sunshine, cooler temperatures, and light winds.
Temperatures will be notably cooler and widespread cloud cover is expected for portion of E OK / NW AR however any fire starts should be expected to spread quickly.
An upper low was seen on satellite imagery over the southern Manitoba/Saskatchewan border. It is forecast to move southeast today and as it does an area of low pressure will develop near the WI/MN/IA border region this afternoon. The low will move little tonight then it's expected to move southeast on Friday. The low will have PW values around 0. Area radars show light precipitation moving into western portions of the Northland as of 10Z and observations have shown a mix including just rain as surface temperatures have risen above freezing in spots. The overall trend though has been toward a shift south with the higher amounts.
Main aviation concern will continue to be gusty west to northwesterly winds in the wake of today's cold frontal passage. Will carry the light snow mention at XNA/ROG but leave it out at FYV for now, with some signs that even the lower ceilings may remain north of FYV until after 00Z Sat. Temperatures will be notably cooler and widespread cloud cover is expected for portion of E OK / NW AR however any fire starts should be expected to spread quickly.
419 PM MST Thu Jan 14 2021 Rapidly deepening low pressure continues to dig across Iowa and the Middle Mississippi River Valley, with high pressure slowly moving east across the Pacific Northwest.
For this reason will keep most of the winter weather advisory going, as it will cover both freezing drizzle/mixed precipitation as well as patchy blowing snow impacts. This weekend will be rather quiet, with temperatures a bit cooler.
527 PM CST Thu Jan 14 2021 For 01/15/2021 00Z TAF issuance Dry cold frontal boundary sliding through the region this evening. /issued 243 PM CST Thu Jan 14 2021/ Other than being a little breezy with a few high clouds streaming in ahead of the cold front it has been a mild afternoon across the area. The cold front will move quickly across the area this evening and overnight, but will remain dry across the inland zones.
It will remain dry through this evening with mostly clear skies to start, then we'll see increasing clouds during the overnight hours as a weak cold front approaches the coast.
404 PM MST Thu Jan 14 2021 A deep trough currently tracking its way southeast across the central CONUS and a ridge of high pressure just of the California coast is keep us under a tightened pressure gradient. With the jet positioned just east of our forecast area, the higher elevations are experiencing some strong and gusty winds this afternoon.
/issued 1256 PM CST Thu Jan 14 2021/ A low pressure system moves south over the Rockies and into the upper MS River valley early Friday. The low continues to push east over the Great Lakes and into Canada.
Thus, we will maintain current wind headlines and expand the High Wind Warning into far northeastern KS tonight, where winds could gust to 60 mph.
This feature could cause moments of lowered visibility but isn't expected to allow for much accumulation as temperatures are well above freezing for the moment. The cold front that moved through this morning is situated well off to the east allowing for a modest pressure gradient across much of Nebraska and western Iowa. Aloft the 12z upper-air analysis shows a broad upper level ridge over the western CONUS and a rather impressive 180 kt jet on its downstream flank.
Will let the High Wind Warning continue for these locations, but have cancelled southern Bighorn county. Dry conditions will prevail tonight and most of Friday as we undergo a period of upper level ridging. By tomorrow night a weak Pacific wave will break down the ridge and bring a brief shot of light rain/snow showers to mainly our mountains and upslope areas southeast of Billings. The high elevations will likely pick up a couple inches of snow.
Still possible to see a rain/snow mix across the higher elevations overnight tonight as rain overspreads the area with a frontal passage.
321 PM MST Thu Jan 14 2021 Rapidly deepening low pressure continues to dig across Iowa and the Middle Mississippi River Valley, with high pressure slowly moving east across the Pacific Northwest.
Friday evening deep moisture under the upper low will move back in from the west. This combination results in a good chance of both stratiform and convective precip, mainly in the form of snow, even with temperatures above freezing for most area until late at night. Once temperatures fall to freezing, light accumulations will be possible later in the night. The highest elevations will be below freezing all night and stand the best chance of accumulations. Persistent troughing will dominate through the upcoming weekend, with a couple of weak mid level impulses providing a few periods of enhancement to the ongoing snow showers and flurries.
This Evening Through Thursday Upper trof extends from Winnepeg area to Missouri Valley with strong jet stream behind it over forecast area while upper ridge builds over western US. UNR recently had a gust of 77 mph, the highest for this wind event. Forecast area will remain under northerly jet through Friday as upper low moves southeast and upper ridge flattens as it moves over the Rockies.
At the surface deep low pressure is situated over MN with high pressure over the Northern/Central Rockies, setting up strong pressure gradient over the Plains. Deep upper low will slowly migrate across northern MO into central IL on Fri keeping very anomalous deep northwest flow over the Plains. Very strong northwest winds will continue to plague central and eastern Kansas tonight and Friday as low pressure continues to deepen across eastern Iowa into western Illinois. Mid-level moisture will wrap around the low, moving across the area with some virga/isolated showers of rain this evening and snow on Friday. The higher end of this range still looks to be for areas along and especially west of I-135.
Although latest IR satellite data confirms that a pronounced increase in high-level clouds can be expected through sunset, moderate SSW flow in the boundary layer will ensure that temperatures will remain pleasantly warm ranging from the lower 50s east-to around 60 in the west. Latest near term model guidance still suggests that the mid-level trough will deepen further and close off overnight, with the developing cyclone aloft expected to track very slowly eastward across southeastern IA/northwestern MO.