Aikyam-Lab/Synoptic-Bench huggingface dataset:
THIS AFTERNOON: Mid-lvl vorticity within a broad upper trough continues to moves through the Tri-State are this afternoon. With this afternoon's passage of a secondary cold front, we've already started seeing temperatures fall a bit, and this trend will amplify after dark. These weakening or even variable winds should prevent most areas west of I-29 from reaching extreme cold criteria (-35F), but areas along the higher elevations of the Coteau will continue to see warning level conditions. Areas most likely to linger near or below -25F will be in the higher elevations of SW Minnesota and Iowa.
From here, expect our temperatures to peak in the mid to upper teens and 20s for the day as a warm front scoots across the state.
(Today) An upper trough was dropping southeast through the lower MO valley, with a secondary Arctic front at the surface pushing into southern IL, southeast MO into AR. Bands of mostly mid and high level moisture was associated with this front and trough. High temperatures today will reach the upper 20s to around 30 in valleys areas, and middle 20s atop the higher plateaus.
719 AM EST Tue Jan 21 2025 High pressure will gradually build in from the west through midweek.
With the thermal trof currently on top of the state and expected to move east, warm advection increases through the day.
A cold front is moving through area this morning and will continue its eastward movement today. A healthy northwest wind behind the front will keep wind chills in the -10 to 10 range today with the lower values further north and west. On Wednesday we will be between two troughs and should see a return to southerly low level flow. Highs will slowly climb to around the freezing mark.
Aside from two notable exceptions, which we will get to a bit later, the general rule for the region will be persistent upper level ridging over the eastern Pacific and just offshore of the West Coast, and very strong and broad troughing over almost the entire continent. This will keep the area generally under high pressure with north flow aloft. In the low to mid levels, dry east flow will prevail, with downslope effects keeping ridges and midslopes warm and very dry, with strong inversions trapping colder, moist air in the valleys, especially west of the Cascades.
(Rest of Today) A surface cold front is currently right on our doorstep to our northwest.
403 AM EST Tue Jan 21 2025 Arctic high pressure will build across the region through Wednesday.
WEATHER PATTERN OVERVIEW: The influence of a slightly warmer air mass is already being felt with warmer temperatures pushing in from the west, as an upper level ridge climbs up and over the northern Rockies creating a chinook.
Pattern Synopsis: Strong, expansive longwave troughing draped across most of the continent east of the Rockies will slide east today. A second trough looks to dig across southern Canada over the northern Great Plains, strengthening a cyclone that will trek into the Upper Midwest by the end of the period.
On the bright side, afternoon highs will climb anywhere from 5-15 degrees warmer than what was recorded across our CWA yesterday. This trend of warmer daytime highs will continue through the end of the week. Arizona will settle between a large trough to our east and a building ridge across the West Coast.
247 AM MST Tue Jan 21 2025 -Breezy to windy and becoming warmer today -A clipper system will bring wind and light snow tonight through Wednesday night. Moderate to locally heavy snow accumulations are possible in the northern Black Hills The deep upper trough has shifted off to the southeast of the forecast area as an upper ridge builds in from the west. The center of the arctic high has moved out of the forecast area with a lee side trough developing to the east of the northern Rockies. Warm westerly flow will try to scour out any remaining Arctic air today, with the flat upper ridge moving overhead ahead of an approaching clipper.
505 AM CST Tue Jan 21 2025 (Today through Wednesday Night) A new cold front is pushing SE through the state early this Tue morning.
(Tuesday through Wednesday) The highly advertised winter weather event continues to unfold across the region this morning. The Winter Weather Advisory is now set to expire at 10 AM this morning, as models have a cold front pushing the precipitation out of the forecast area around that time. Despite the afternoon sunshine, temps will likely only top out in the mid to upper 30s this afternoon, with some slightly cooler highs in areas with a snowpack.
351 AM CST Tue Jan 21 2025 (Today) An upper trough was dropping southeast through the lower MO valley, with a secondary Arctic front at the surface pushing into southern IL, southeast MO into AR. Bands of mostly mid and high level moisture was associated with this front and trough. High temperatures today will reach the upper 20s to around 30 in valleys areas, and middle 20s atop the higher plateaus.
432 AM MST Tue Jan 21 2025 -Breezy to windy and becoming warmer today -A clipper system will bring wind and light snow tonight through Wednesday night. Moderate to locally heavy snow accumulations are possible in the northern Black Hills The deep upper trough has shifted off to the southeast of the forecast area as an upper ridge builds in from the west. The center of the arctic high has moved out of the forecast area with a lee side trough developing to the east of the northern Rockies. Warm westerly flow will try to scour out any remaining Arctic air today, with the flat upper ridge moving overhead ahead of an approaching clipper.
606 AM CST Tue Jan 21 2025 (Tuesday through Wednesday) The highly advertised winter weather event continues to unfold across the region this morning. The Winter Weather Advisory is now set to expire at 10 AM this morning, as models have a cold front pushing the precipitation out of the forecast area around that time. Despite the afternoon sunshine, temps will likely only top out in the mid to upper 30s this afternoon, with some slightly cooler highs in areas with a snowpack.
936 AM EST Tue Jan 21 2025 High pressure will gradually build in from the west through midweek.
After today, ridging remains the dominant weather feature with troughing much further east, reducing the gradient and relaxing our winds over the next several days. Valley lows are expected to be in the 30s through midweek with several sites at or near freezing, particularly in the central Sacramento Valley east of I-5. NBM chances show a 30-55% chance of temperatures below freezing this morning across parts of the Central Valley, highest along the eastern portions of the Valley and from the Delta to the Greater Sacramento Area. There is an additional 40 to 70% chance for below freezing temperatures Wednesday morning as well, though chances are more or less limited to areas of the Valley that are near Yuba City and southward. Valley highs will be in the upper 50s to low 60s each day with cooler temps as you increase in elevation.
Discussion: In the upper levels, a deep trough is over the U. At the surface, high pressure will be over the Ohio Valley. Little to no accumulation is expected since the low is very far away over the Gulf. Wind chills around 10 below are possible in the higher elevations of the East Tennessee mountains. With sunny skies, highs will be in the lower 30s for most of the Tennessee Valley.
Upper level longwave trough will continue propagating east through the short term period. At the surface, the strong 1045-1050 high pressure will continue to make it's presence known through the day.
1033 AM MST Tue Jan 21 2025 -Breezy and becoming warmer today -A clipper system will bring wind and light snow tonight through Wednesday night. Warmer air is beginning to filter into the region from the west, however still seeing wind chill values over much of northeastern Wyoming and western South Dakota ranging from 15 to 25 below zero. The deep upper trough has shifted off to the southeast of the forecast area as an upper ridge builds in from the west. The center of the arctic high has moved out of the forecast area with a lee side trough developing to the east of the northern Rockies. Warm westerly flow will try to scour out any remaining Arctic air today, with the flat upper ridge moving overhead ahead of an approaching clipper.
Temperatures this morning were slightly warmer than previous morning, yet we still had areas with temperatures and/or wind chills below -20.
804 AM MST Tue Jan 21 2025 -Breezy and becoming warmer today -A clipper system will bring wind and light snow tonight through Wednesday night. Warmer air is beginning to filter into the region from the west, however still seeing wind chill values over much of northeastern Wyoming and western South Dakota ranging from 15 to 25 below zero. The deep upper trough has shifted off to the southeast of the forecast area as an upper ridge builds in from the west. The center of the arctic high has moved out of the forecast area with a lee side trough developing to the east of the northern Rockies. Warm westerly flow will try to scour out any remaining Arctic air today, with the flat upper ridge moving overhead ahead of an approaching clipper.
Ridging increasing tonight resulting in slightly less winds, but clearing skies will allow for ambient temperatures dipping further below zero, especially for northeastern Vermont where minus 20F is in the realm of possibility.
Temps range from the upper teens to the lower 20s with wind chills from the mid single digits to the mid teens.
1054 AM EST Tue Jan 21 2025 Arctic high pressure will build across the region through Wednesday.
One area will be in the most northwestern mountainous counties thanks to upslope precipitation from a weak cold front associated with an upper low.
Updated at 100 PM CST Tue Jan 21 2025 - Warmer temperatures through the end of the week.
The fog seemed to be thickest across the nearshore waters north of the island chain as well as the Lower Keys, where visibility got as lows as 2 miles at the Key West International Airport. Aloft the low-mid level front is stalled back to our north and northwest and is one of the main reasons why we still have a mid deck of stratus. Light to gentle northeast to east breezes will prevail this afternoon into this evening across the Keys waters, before another cold front pushes through the area late tonight into Wednesday morning.
1141 AM CST Tue Jan 21 2025 (Rest of Today) A surface cold front is currently right on our doorstep to our northwest.
Temperatures are gradually rising this morning after falling to subfreezing lows across most of the area. The low temperature reported at Harry Reid Airport in Las Vegas was 29 degrees, which was the first sub-30 degree low in over three years. Breezy northerly winds are still expected in the lower Colorado River Valley near Laughlin and Lake Mohave this morning, decreasing in the afternoon.
1120 AM CST Tue Jan 21 2025 (TODAY THROUGH WEDNESDAY NIGHT) A NEW COLD FRONT IS PUSHING SE THROUGH THE STATE EARLY THIS TUE MORNING.
(This evening through Wednesday) The upper trough axis has pushed to the south of the FA as of 18Z. Despite a morning cold front, guidance has afternoon temps warming into the 40s and 50s tomorrow afternoon. Regardless, this cold front will feel warm compared to yesterday's.
1252 PM EST Tue Jan 21 2025 Arctic high pressure will build across the region through Wednesday.
Observations to the west of this boundary have remain rather cloudy with north to northeast winds and temperatures in the lower 70s. As the low and mid level front catches up, it will surge across the area from the northwest to southeast. Before this occurs the biggest question mark is will we see fog develop again, especially since we have gone southerly in the eastern waters with dew points in the lower 70s! In addition, there is quite a bit of moisture associated with the upper level front and therefore have increased slightly the rain chances for Wednesday as it sweeps through.
- Warmer conditions return for late week into the weekend. Coldest temperatures will be south of the Big Country, where overnight lows will be in the lower 20s. Slightly warmer temperatures are expected across the Big Country, with overnight lows in the mid 20s. Lee trough develops tonight, with south winds developing and becoming gusty after midnight into tomorrow morning. Will go ahead and issue a Cold Weather Advisory for areas south of Interstate 20 from midnight through 9 AM tomorrow morning due to the low wind chills. We finally warm up a bit tomorrow, with afternoon highs topping out in the low to mid 50s under full sunshine.
This has resulted in increased offshore flow with gusty breezes and lower relative humidity near and at the ridges in southwest Oregon, Siskiyous, western Siskiyou county and ridges east of the Cascades, the winds in these areas will gradually diminish later this afternoon with lighter winds expected this evening and tonight. The thermal trough will srengthen again Wednesday with seas expected to become steep south of Cape Arago, generally beyond 5 nm from shore but also near shore of Cape Blanco. There's good agreement for a further increase with moderate to strong north winds later in the week through the weekend due to a strong thermal trough developing along the coast.
- Snow showers may also pass through Wednesday afternoon with another cold front. With associated upper trough crossing the Northern Rockies. High resolution guidance is all over the place, likely due to the difficulty in pinpointing mesoscale vorticity within the upper trough, along with the lingering dry air in the low levels. WEDNESDAY: Snow may be lingering along the Highway 20 corridor through the mid-morning hours, with a lull in areas further north. By mid-day, another compact lobe of vorticity within the upper trough moving towards the Great Lakes will drop southward. A slightly stronger cold front and wind shift to the north moves in early in the evening, dropping temperatures once again while maintaining some low end flurry risks into the early overnight.
1222 PM CST Tue Jan 21 2025 - A warm front will continue to move through the area today, warming temperatures back to near normal.
Northwest flow aloft will increase mixing and bring warmer temps aloft across SE Oregon (Burns to Rome) while cold air remains trapped near the surface along the I-84 corridor.
This trend will continue into the early afternoon where all precipitation will come to an end as a reinforcing cold front sweeps across the area. Kovacik (Tuesday through Wednesday) The highly advertised winter weather event continues to unfold across the region this morning. The Winter Weather Advisory is now set to expire at 10 AM this morning, as models have a cold front pushing the precipitation out of the forecast area around that time. Despite the afternoon sunshine, temps will likely only top out in the mid to upper 30s this afternoon, with some slightly cooler highs in areas with a snowpack.
Temperatures will rise to above freezing across the entire area, but remain on the cold side today in the mid 30s to low 40s. Additionally, with freezing temperatures overnight, any residual moisture will refreeze which could lead to patchy black ice. Cloud cover increases Wednesday night and another weak cold front moves across the area overnight.
A weak cold front will bring less than a half inch of snow to portions of central Illinois Wednesday night. This afternoon, a cold air mass associated with a 1040mb ridge originating from the Arctic a few days ago and now extending from Texas across Illinois continues to drive well below normal temperatures across central Illinois. Mid level warm air advection behind the departing low level ridge and ahead of an approaching upper trough will be in place through at least the first half of the day Wednesday and will help moderate temps across the region. Probability of exceeding 30 degrees has lowered for Wednesday, now only about 15 percent near the lower Illinois River.
Mid afternoon satellite imagery/RAP analysis showed a sharp upper level trough just northwest of our CWA that will swing across the region tonight and then off the east coast Wednesday. This upper level trough will support the cold front and help usher in a reinforcing shot of cold dry air. This will help provide us with dry weather and allow temperatures warm above freezing during the afternoon.
Additionally model soundings in the Rouge Valley suggest the low levels will remain dry tonight.
334 PM CST Tue Jan 21 2025 - Warmer temperatures are on the way. These gusty winds continue to usher warmer air into the region and we will see some of the benefits of it tomorrow when above freezing temperatures are able to mix down to the surface Wednesday afternoon. This sends another cold front through the region. Moisture is limited and so snowfall totals should remain on the low side, thinking of a range between a dusting and a few hundredths of an inch for most of the area.
236 PM MST Tue Jan 21 2025 KEY MESSAGES: - Warmer temperatures have arrived and will generally prevail throughout the forecast period.
An additional round of light snow is possible late tonight through Wednesday (30 to 40 percent chance) as a cold front moves through the state.
627 PM EST Tue Jan 21 2025 Arctic high pressure will build across the region through mid week.
601 PM CST Tue Jan 21 2025 Updated at 556 PM CST Tue Jan 21 2025 - Warmer temperatures through the end of the week.
The emergence of late afternoon sun has allowed for portions of our area to rise above the freezing mark over the past hour or so, and a bit of melting is expected to take place heading into the evening. Despite this, we expect a fairly quick return of subfreezing and eventually dangerously cold temperatures overnight. This will result in a refreezing along area roadways, and as such travel conditions will likely remain extremely hazardous heading into tomorrow morning. While not as cold as tonight, another round of subfreezing lows is expected tomorrow night with most locations in the 20s/near 30.
514 PM EST Tue Jan 21 2025 Arctic high pressure will build across the region through mid week.
A dusting up to half an inch is expected with areas in northeast MO most likely to see the higher amounts. - Slight warm up anticipated for Wednesday with highs in the low to upper 30s across the area.
526 PM CST Tue Jan 21 2025 - Warmer temperatures are on the way. These gusty winds continue to usher warmer air into the region and we will see some of the benefits of it tomorrow when above freezing temperatures are able to mix down to the surface Wednesday afternoon. This sends another cold front through the region. Moisture is limited and so snowfall totals should remain on the low side, thinking of a range between a dusting and a few hundredths of an inch for most of the area.
As an arctic high continues to move off to the east, now southwesterly flow will bring warmer air into the region throughout this evening and overnight, causing temperatures to continuously increase. There are signals in the high res models for a locally higher snow total of 3 inches for portions of the North Shore from lake enhancement from south to southwesterly flow. Once the cold front moves through and flow switches to the northwest, lake effect snow will start up once again along the South Shore.
254 PM MST Tue Jan 21 2025 - Expect overnight lows that are less cold than last night as warmer air advects over the region. Later tonight another low amplitude mid-level short wave trough brushes the northern Colorado mountains resulting in lowering clouds and a slight chance for light snow showers toward morning. A secondary, more energetic short wave trough moves southeastward over the northern and central Colorado mountains Wednesday morning through early Wednesday afternoon. Snow decreases from late afternoon Wednesday into Wednesday evening before yet another short wave trough brushes the northern and central Colorado mountains overnight.
Quiet weather will continue through the week with cold overnight lows and warmer than normal afternoon highs.
524 PM CST Tue Jan 21 2025 (Tonight) A surface cold front is currently progressing over northwestern Alabama and is forecast to move southeast of the local area this evening. Additionally, while winds will remain around 5 mph or less (perhaps a touch stronger in the higher elevations in northeast Alabama), wind chills are still forecast to be dangerously cold.
436 PM MST Tue Jan 21 2025 - Expect overnight lows that are less cold than last night as warmer air advects over the region. Later tonight another low amplitude mid-level short wave trough brushes the northern Colorado mountains resulting in lowering clouds and a slight chance for light snow showers toward morning. A secondary, more energetic short wave trough moves southeastward over the northern and central Colorado mountains Wednesday morning through early Wednesday afternoon. Snow decreases from late afternoon Wednesday into Wednesday evening before yet another short wave trough brushes the northern and central Colorado mountains overnight.
1012 PM EST Tue Jan 21 2025 Arctic high pressure will build across the region through mid week.
For tomorrow, temps have also been reduced a tad as areas that see snowpack will struggle to get above freezing.
927 PM MST Tue Jan 21 2025 - Expect overnight lows that are less cold than last night as warmer air advects over the region. Later tonight another low amplitude mid-level short wave trough brushes the northern Colorado mountains resulting in lowering clouds and a slight chance for light snow showers toward morning. A secondary, more energetic short wave trough moves southeastward over the northern and central Colorado mountains Wednesday morning through early Wednesday afternoon. Snow decreases from late afternoon Wednesday into Wednesday evening before yet another short wave trough brushes the northern and central Colorado mountains overnight.
Surface analysis from available land- and sea-based observations depict what was once a stationary front impacting the Keys forecast area slowly progressing northwestward north of the Island Chain as a warm front. Meanwhile, a strong cold front extending from the central Gulf of Mexico northeastward to central Florida is slowly progressing southwestward. Ahead of a cold front, breezes are light and conditions are near saturation over the cooler waters north of the Island Chain. This cold front will push through the remaining Florida Keys marine zones on Wednesday morning, bringing a surge of strong north to northeast breezes.
1123 PM CST Tue Jan 21 2025 (Tonight through Wednesday night) Key Messages: - Freezing temperatures again tonight and Wednesday night. The winter weather mix of sleet, freezing rain and snow in some locations, has ended. Skies are expected to clear from west to east through the evening hours as high pressure settles across the region. A light southerly flow is progged to develop Wednesday leading to increasing low level moisture and slightly warmer temperatures by Wednesday afternoon. Another surge of high pressure and cold air advection Wednesday night will lead to another night of freezing temperatures across most of S TX. However, lows will be 6-10 degrees warmer than tonight's forecasted values.
Strong winds above the boundary layer will mix to ridges tomorrow, but most valleys will remain light and variable.
This will lead to another fair weather day as strong high pressure crests overhead this afternoon. High pressure moves offshore tonight as a weak warm front pushes into the region from the southwest. This will result in increasing clouds will will also aid in warmer overnight temps then what we've seen the last few nights.
929 PM CST Tue Jan 21 2025 - Another round of light snow is possible late tonight through Wednesday (30 to 40 percent chance) as a cold front moves through the state.
High pressure will slip by to our south today, allowing for plenty of sun, though high temperatures will still be cold in the single digits to mid teens and apparent temperatures about 10 degree colder. This system will also bring in slightly milder air with southerly/southwesterly flow, allowing temperatures to reach into the upper teens to mid 20s, much warmer than previous days.