Aikyam-Lab/Synoptic-Bench huggingface dataset:
1023 AM MST Sat Nov 21 2020 Current surface analysis shows a nearly stationary frontal boundary to the north of the region, with an area of high pressure centered to the east. A developing trough is located to the lee of the Rockies. Weak cold front passages in west-northwest flow will help to produce gusty winds at times, but little in the way of moisture for most areas.
/issued 906 AM EST Sat Nov 21 2020/ High pressure to the north of the area will maintain a northeast to easterly wind flow across the forecast area the remainder of today. Adequate low level moisture below a subsidence inversion around 825MB (via 12Z Raob data) will support intervals of clouds and possibly a few sprinkles or isolated showers the remainder of today, mainly from the I-4 corridor south where the best moisture will reside, otherwise breezy and warm conditions with afternoon temperatures climbing into the lower 80s can be expected. High pressure northeast of the waters will maintain a 5-6Mb gradient over the Gulf waters the remainder of today.
Another pretty day on tap for the Mid-South with highs today in the lower 70s. /issued 351 AM CST Sat Nov 21 2020/ A cold front is currently moving into southern Missouri and western Kentucky early this morning while high pressure covers the southeast states. Expect the cold front to become stationary just north of the forecast area today due to a blocking ridge to the southeast. The frontal boundary will become a cold front again tonight as it progresses through the forecast area on Sunday.
332 PM EST Sat Nov 21 2020 High pressure to the north will continue to weaken tonight as a coastal trough develops offshore. The coastal trough will lift inland Sunday and Sunday night ahead of an approaching cold front.
Winds have been light and variable aiding sunshine warmed ground in heating of the lower air. A cold front will be arriving around midday on Sunday and shifting S/SW wind 5KT to Westerly 5KT with a few showers possible.
Onshore flow and coastal trough continues to produce enough low level convergence along the NE FL coastal areas for scattered showers at times that will push inland through the St Johns River Basin and US 301 Corridor before fading as they reach inland NE FL.
Lows tonight in the low to mid 30s. High pressure follows in wake of short term sys Mon ahead of potent srn Rockies sw ejecting out through the plains late Tue and OH valley Wed. Strong low level warm advection ahead of this sys may yield some light rain Tue morning within leading warm advection wing however bulk of rain will hold off until Tue night in association with broad/moist warm conveyor belt ahead of occluding sfc cyclone and persist through Wed as sys is slow to lift out.
920 AM CST Sat Nov 21 2020 Early morning fog has dissipated over the lower Acadiana region.
(This evening through Sunday) The slow-moving cold front will clear the Red River late this eveing.
1228 PM EST Sat Nov 21 2020 Cooler and mainly dry conditions are expected today with precipitation moving back in tonight into Sunday. Precip will start as rain for the entire area, with wet bulb zeros dropping late tonight into Sunday morning to near freezing. Thermal profiles have suggested that temperatures may be just warm enough across the southeast to limit snow accumulation on mainly grassy surfaces with better potential a bit further north where lows near/below freezing expected. Temperatures are expected to climb back well above freezing on Sunday so any slick spots will quickly improve. High pressure will briefly build in with increasing upper level heights into the start of the work week.
Upper level ridging will translate eastward over the area Sunday into Sunday night. In fact, return southerly flow will have already developed after mid- afternoon for areas west of HWY 83 as the ridge axis quickly shifts east.
242 PM EST Sat Nov 21 2020 Upper level ridging across the southeastern U. and north Florida this afternoon will move east into the Atlantic through Sunday as a mid level trough moves eastward into the eastern U. As mentioned above a mid level trough moving into the eastern U.
1119 AM EST Sat Nov 21 2020 Scattered showers are expected today before widespread rainfall will return Sunday morning with a crossing cold front. Additional rainfall is expected midweek with crossing low pressure. Moisture will increase once again late tonight as a warm front lifts north. Stratiform rain is progged by Sunday morning with the warm front, then more substantial rainfall is expected Sunday afternoon and evening with the crossing cold front.
251 PM CST Sat Nov 21 2020 (Issued 253 PM CST Sat Nov 21 2020) Tonight through Sunday night: High pressure will hang tough through Sunday night, keeping us mostly dry as a storm system passes to our south. Highs tomorrow will reach the low to mid 40s.
With that, temperatures are climbing as expected amidst abundant insolation as the cold front and associated dense sky cover remains to the north over portions of KY, albeit stretching into southwest VA as well. On Sunday winds will increase out of the south ahead of an approaching cold front, with low VFR cu expected at all sites. CDG Chattanooga Airport, TN 49 68 43 58 37 / 0 20 60 0 0 Knoxville McGhee Tyson Airport, TN 46 66 42 54 34 / 0 20 70 0 0 Oak Ridge, TN 47 65 41 54 34 / 0 30 70 0 0 Tri Cities Airport, TN 44 65 39 52 30 / 0 10 80 10 0.
With that, temperatures are climbing as expected amidst abundant insolation as the cold front and associated dense sky cover remains to the north over portions of KY, albeit stretching into southwest VA as well. CD Chattanooga Airport, TN 70 49 67 43 58 / 0 0 30 60 0 Knoxville McGhee Tyson Airport, TN 67 46 66 42 54 / 0 0 30 70 0 Oak Ridge, TN 67 47 65 41 54 / 0 0 40 70 0 Tri Cities Airport, TN 66 44 64 39 52 / 0 0 20 80 10.
254 PM CST Sat Nov 21 2020 Lower atmosphere will gradually moisten overnight in south-southeast low level flow, then further moisten near or a little before daybreak Sunday as a cold front sloshes back south through the area. Sunday will see very light showers or drizzle decreasing for the most part by the afternoon but still moist and cooler than normal through the day.
Current water vapor imagery and RAP upper air analysis indicate an upper level ridge centered just off the GA coast with widespread dry air across the Southeastern U. Further to the northwest, there is a low amplitude trough moving out of the Rocky Mountains into the Great Plains. The trough to the northwest will amplify somewhat tonight as it dives into the central Plains. A cold front will race across the area Sunday afternoon and evening.
227 PM CST Sat Nov 21 2020 Much cooler and more moist conditions are on its way to west Texas and southeast New Mexico for Sunday as a cold front heads south into the region late tonight and continues into the Big Bend Sunday. After a very mild night, temperatures will be much cooler and below normal Sunday with a considerable amount of clouds expected.
The stalled frontal boundary which is the focus for patchy light rain from Indiana to Zanesville will lift northward tonight with the advance of low pressure. More substantial rainfall is expected on Sunday with low passage and subsequent cold front passage.
As the upper level trough continues to approach the area from the west we will see more bands of heavier rain and a few storms develop across the area this afternoon and evening. The trough will track across the region tonight as the rain will end from west to east overnight into early Sunday.
Additional rainfall is expected midweek with crossing low pressure. Moisture will increase once again late tonight as a warm front lifts north. Light rain is progged by Sunday morning with the warm front followed by more substantial rainfall during the afternoon and evening with the crossing cold front.
Surface cold front has sagged through the Panhandle and into the Red River Valley. Weak cold advection behind the front plus increase in cloud cover will allow for cooler conditions areawide.
Roxy MORNING DISCUSSION: Synoptic Setup: Forecast begins with northeast Montana under a slight trough with high clouds spilling off of the Front Range. Over the Pacific Northwest a ridge runs north into British Columbia and is progressing forward. Behind this a series of sub- synoptic ridges and troughs lie in the flow over the Pacific bringing a very progressive pattern to the area, but surprisingly limited moisture. Today into Sunday night: Trough will exit to the east tonight allowing the ridge to move on through.
Temperatures have still managed to rise this afternoon to the low to mid 70s across the area. Short range models show showers moving into the area tonight into tomorrow morning along and ahead of a cold front. Expect the cold front to become stationary just north of the forecast area today due to a blocking ridge to the southeast. The frontal boundary will become a cold front again tonight as it progresses through the forecast area on Sunday.
A weak upper trough will move over Central CA tonight into Sunday. The trough will bring in a slightly cooler airmass which will translate to Sunday being our chilliest morning for the weekend and we could see patchy fog/frost especially in the North Bay valleys. Sunday highs will also trend cooler by about 2-6 degrees than today.
The trough is forecast to amplify as it swings through the Mississippi River Valley and into the Ohio Valley tomorrow. An associated surface cold front will push into northwest portions of the area by late tomorrow afternoon. Cloud cover will increase across the ArkLaMiss Delta tomorrow as the front encroaches on the area, however expect another warm afternoon with high temperatures in the low to upper 70s.
858 PM CST Sat Nov 21 2020 (Issued 900 PM CST Sat Nov 21 2020) High clouds will continue to stream across southern Wisconsin overnight as low pressure continues to develop along frontal boundary draped across central and eastern CONUS. Kavinsky (Issued 253 PM CST Sat Nov 21 2020) Tonight through Sunday night: High pressure will hang tough through Sunday night, keeping us mostly dry as a storm system passes to our south. Highs tomorrow will reach the low to mid 40s.
There may have even some weak compressional heating with a little mid level high that developed overhead today ahead of the approaching cold front. The cold front will slowly edge into the I-30 corridor overnight and dig down into the I-20 corridor mid to late morning in E TX and NW LA and then on down the I-49 corridor during the afternoon. Overnight much colder with clearing skies and fresh high pressure settling in for the night.
536 PM CST Sat Nov 21 2020 (This evening through Sunday) The slow-moving cold front will clear the Red River late this eveing.
537 PM CST Sat Nov 21 2020 A slow moving cold front will continue to move its way southeast across Arkansas tonight through Sunday morning.
410 PM MST Sat Nov 21 2020 Progressive westerly flow will become a little more active as passing upper troughs trend more amplified.
A cold front will move across the region after 22/12Z with southwest winds becoming northwest behind it and increasing to 10kts. There may have even some weak compressional heating with a little mid level high that developed overhead today ahead of the approaching cold front. The cold front will slowly edge into the I-30 corridor overnight and dig down into the I-20 corridor mid to late morning in E TX and NW LA and then on down the I-49 corridor during the afternoon. Overnight much colder with clearing skies and fresh high pressure settling in for the night.
But latest runs of the High Resolution Rapid Refresh Model (HRRR) are pessimistic about this idea with just a small area of fog indicated near Visalia. There is a weak s/wv trough just upstream of the clouds that will move inland overnight as well.
Decent looking mid-level trof/PV anomaly will work its way across the region through tonight. An addition, a nice, sharp H7 thetaE ridge is progged to move over the forecast area under a jet streak aloft. For the most part it'll be rain, but with some snow toward mid-evening, and mainly over the higher elevations of the Coteau/Sisseton Hills. Ridging aloft then builds into the region for Sunday and Sunday night with generally dry conditions anticipated.
Ridging will increase on Sunday, with another dry and relatively pleasant day expected with temperatures similar or slightly warmer than today.
The stalled frontal boundary which is the focus for patchy light rain from Indiana to Zanesville will lift northward late tonight with the advance of low pressure. More substantial rainfall is expected on Sunday with low passage and subsequent cold front passage.
/Issued 600 PM EST Sat Nov 21 2020/ Another nice day expected across the area with high pressure at the surface and aloft. Mid-level high pressure across the area is expected to weaken and shift east as a trough develops across much of the eastern US.
The low stratus layer will be in the process of being scoured out of the area early Sunday morning.
/Issued 257 PM EST Sat Nov 21 2020/ Another nice day expected across the area with high pressure at the surface and aloft. Mid-level high pressure across the area is expected to weaken and shift east as a trough develops across much of the eastern US.
/issued 254 PM CST Sat Nov 21 2020/ Lower atmosphere will gradually moisten overnight in south-southeast low level flow, then further moisten near or a little before daybreak Sunday as a cold front sloshes back south through the area. Sunday will see very light showers or drizzle decreasing for the most part by the afternoon but still moist and cooler than normal through the day.
Clouds will decrease this evening as ridging builds in from the west. Sunday will start off mostly sunny as a transient ridge axis passes over the Four Corners region. The ridge will move east of the divide by afternoon allowing southwest flow aloft to return.
840 PM CST Sat Nov 21 2020 Benign weather is continuing across the Tennessee Valley this evening, with high pressure still situated just east of the area. However, high clouds will continue to filter into the region overnight as a cold front gradually moves from the Southern Plains toward the mid/lower Mississippi Valley. The end result will be a fairly mild night with an overcast sky developing -- and southerly winds helping to keep lows in the lower 50s. A cold front will race across the area Sunday afternoon and evening.
This will change tonight however, as a cold front makes its way into the area. /issued 227 PM CST Sat Nov 21 2020/ Much cooler and more moist conditions are on its way to west Texas and southeast New Mexico for Sunday as a cold front heads south into the region late tonight and continues into the Big Bend Sunday. After a very mild night, temperatures will be much cooler and below normal Sunday with a considerable amount of clouds expected.
Lows tonight in the low to mid 30s. High pressure follows in wake of short term sys Mon ahead of potent srn Rockies sw ejecting out through the plains late Tue and OH valley Wed. Strong low level warm advection ahead of this sys may yield some light rain Tue morning within leading warm advection wing however bulk of rain will hold off until Tue night in association with broad/moist warm conveyor belt ahead of occluding sfc cyclone and persist through Wed as sys is slow to lift out. Fast changes in ceiling and visibility conditions are just ahead as a low pressure area moves northeast into far southern Indiana late tonight and then northeast into Ohio later in the day Sunday.
733 PM EST Sat Nov 21 2020 Mid/upper level ridging continues across FL and off the southeast US coast over night then slips east Sun as a trough. At the surface an axis of high pressure from the Atlantic to the Deep South. This is in response to a cold front. accompanying the mid/upper trough. High pressure builds in behind the front with winds veering through mid to late week.
545 PM CST Sat Nov 21 2020 We've had a few sprinkles around the area this afternoon in association with a quick moving upper level short wave trough. Lows tonight will generally be around the freezing mark across our southeast where we will be slower to clear out and in the mid 20s across our northwest where we first see those clear skies. It will be a sunny and dry day with northwesterly flow through the vertical profile as an upper ridge nudges into the plains. The mixing should also give temperatures a slight boost and just a hair warmer than today with highs generally in the lower 50s. The next upper level trough will be tracking through the Rockies with low level moisture flowing north ahead of this trough across the plains.
IFR/LIFR conditions will continue north of cold front as boundary pushes slowly south tonight in response to initial short wave. /Issued 152 PM CST Sat Nov 21 2020/ A cold front stretched from extreme northwest AR to south of Okmulgee early this afternoon, with cloudy, cool, drizzly and showery weather observed north of the boundary. Considerably warmer conditions noted south of the front, along with some breaks/thinning of the cloud cover. A few strong/marginally severe storms aren't out of the question, although updrafts will likely get undercut by the southward moving cold front during the evening hours.
137 PM PST Sat Nov 21 2020 Cooler weather is in store this week with temperatures mostly near to slightly below normal for most days.
359 PM CST Sat Nov 21 2020 We've had a few sprinkles around the area this afternoon in association with a quick moving upper level short wave trough. Lows tonight will generally be around the freezing mark across our southeast where we will be slower to clear out and in the mid 20s across our northwest where we first see those clear skies. It will be a sunny and dry day with northwesterly flow through the vertical profile as an upper ridge nudges into the plains. The mixing should also give temperatures a slight boost and just a hair warmer than today with highs generally in the lower 50s. The next upper level trough will be tracking through the Rockies with low level moisture flowing north ahead of this trough across the plains.
That said, a very rich boundary layer is in place with the low level easterly flow. There is some very weak forcing aloft associated with a very modest H5 inverted trough from the low north of Hispaniola, but the primary feature is a high aloft helping with plenty of subsidence. With the weakening low level flow, frictional/coastal convergence should have less of an impact, but a subtle impulse/trough aloft will begin to build into the region by the end of the forecast period. A mid level trough will advance through the eastern states as low amplitude ridging expands eastward in its wake from the Ohio Valley into the Gulf of Mexico.
149 AM MST Sun Nov 22 2020 500 mb heights build over the region today, then midlevel flow backs to the southwest Monday as a split upper level trof moves into the the Rockies. A few mountain snow showers are possible late Monday into Monday evening as trof axis moves across the area.
Winds could get a bit gusty overnight as the cold front pushes through. A much colder airmass will funnel in behind the surface cold front knocking our lows tonight into the 30s areawide. Temps will struggle to warm tomorrow with highs in the low to mid 50s across the area.
However, conditions will deteriorate later tonight as a cold front moves in from the north. /issued 227 PM CST Sat Nov 21 2020/ Much cooler and more moist conditions are on its way to west Texas and southeast New Mexico for Sunday as a cold front heads south into the region late tonight and continues into the Big Bend Sunday. After a very mild night, temperatures will be much cooler and below normal Sunday with a considerable amount of clouds expected.
Temperatures have still managed to rise this afternoon to the low to mid 70s across the area. Short range models show showers moving into the area tonight into tomorrow morning along and ahead of a cold front. Expect the cold front to become stationary just north of the forecast area today due to a blocking ridge to the southeast. The frontal boundary will become a cold front again tonight as it progresses through the forecast area on Sunday. Showers will exit to the east overnight on Sunday leaving behind much cooler weather on Monday.
As the upper level trough continues to approach the area from the west we will see more bands of heavier rain and a few storms develop across the area this afternoon and evening. The trough will track across the region tonight as the rain will end from west to east overnight into early Sunday. Cooler conditions will occur into Monday as highs in the lower 50s are expected on Monday. An upper level trough will then dig into the southwestern U. Ahead of the trough an upper level ridge will build across the region.
The front will gain momentum later tonight, as an upper trough digs down into the plains and pushes it southward. Expect a reinforcing shot of cool air behind the front as high pressure moves in by Sunday Night.
Mild weather through this weekend will give way to a mainly dry trough producing gusty winds on Monday. Temperatures slowly cool through the week out ahead of a possible late week colder trough. Satellite imagery shows the highest peaks of the White Mountains, San Francisco Peaks and Chuska Mountains causing this altocumulus development.
Weak upper ridging continues to persist over the region tonight with weak westerly upper level flow across the southern United States through the forecast period.
Mid level wave will continue to push through the region overnight, and will give the areal coverage of rain and thunder, along with the cold front a push southeast late tonight and into Sunday morning.
Otherwise dry weather is expected tonight as an upper ridge starts building toward the area from the west. Sun the upper ridge will move over CO but will be quickly followed by the next disturbance. Temps on Sun looks a little cooler, with highs in the 40s to lower 50s over the plains, and mostly in the 40s in the high valleys, with upper 30s to mid 40s in Teller County.
Along with the southwest winds just to the west of the Valley, this has been enough to provide the warmer boost. The timing of precipitation into west central Minnesota by mid to late evening, along with the higher elevation there, would favor this as the best area for 1-2 inches of snow. Since it appears to be a fast moving system, and temperatures have been warmer than anticipated, will not mention any higher end amounts.
Due to the lack of a shrtwv trof the lift/mstr will be shallow and rain amounts still look to be. Precip chances will dwindle Mon especially after 18Z with warmer high temps. Tue a strong mid-latitude cyclone will come out from the 4-Corners region with a 85-95kt 5h jet forecast to move across SE-E NM and W TX.
Upper level ridging will translate eastward over the area Sunday into Sunday night. In fact, return southerly flow will have already developed after mid- afternoon for areas west of HWY 83 as the ridge axis quickly shifts east. The west coast upper level trough will begin to approach the area Monday.
1015 PM EST Sat Nov 21 2020 Currently - Weakening high pressure across the southeast is being bridged by another nigh ridging eastward across the northeast. Lower level ridging to our north continues to weaken and shift northeastward into the Atlantic. Short Term Update - As the high further north bridges into the weakening ridge further south, they will be shifting eastward into the Atlantic. High pressure to our north will shift further northeast and eastward overnight into tomorrow, resulting in winds continuing to gradually relax.
Upper level cloud cover continues to increase from the west ahead of a area of low pressure across the central Mississippi River Valley. The cold front will move into the area Sunday afternoon with showers moving in from west to east. Diegan Chattanooga Airport, TN 48 68 42 57 36 / 0 20 60 0 0 Knoxville McGhee Tyson Airport, TN 45 66 42 54 34 / 0 20 70 0 0 Oak Ridge, TN 45 65 41 55 34 / 0 30 70 0 0 Tri Cities Airport, TN 41 65 39 52 29 / 0 10 80 10 0.