Aikyam-Lab/Synoptic-Bench huggingface dataset:
/Issued 410 AM EDT Sat Oct 9 2021/ Current surface analysis shows a low pressure system off the SE GA coast. Aloft, a longwave trough stretches from the central Great Lakes down to the SE GA coast. NListemaa Upper level pattern across the CONUS will be active through the upcoming week, but our local weather will once again be influenced heavily by a cut-off low.
519 AM MDT Sat Oct 9 2021 Upper air analysis shows the upper trough over the western CONUS and SW flow aloft over the CWA. We can expect another band of precipitation later today on the backside of the low as it pushes through the region. This low pressure system is expected to strengthen also as it moves east of our region, creating a tightening gradient behind it and strong surface winds over the region tonight into Sunday.
The cold frontal passage today, precip chances tomorrow night and then frost concerns for late in the forecast period. An upper level, positively tilted trough will move towards the central CONUS and break into a two, with a northern portion moving across the Dakotas and the southern disturbance moving across northern AZ and NM before tracking over the Texas and Oklahoma panhandles and eventually northward over eastern Kansas. The whole disturbance will cause a cold front to move through the region this afternoon and evening. Precipitation will begin to develop Sunday afternoon and evening along and behind the cold front, but by this time the cold front will be well into southeastern Kansas. Temps behind the cold front for Sunday will knock us back to near seasonal with highs in the low 70s expected for Sunday.
The narrow long wave trough extending south through the Appalachians reaches nearly to Cuba. Subgeostrophic flow rounding the base of the trough axis accelerating to the northeast through the Straits of Florida and Andros continues to produce a thick swath of cirrus within a 70kt jet max. The Lower Keys have recently broken out of the cloud cover.
A surface front associated with a low pressure system currently off the GA/SC coast is slow marching towards us. This trough is expected to become cut-off over the next 24 to 36 hours. Models continue to struggle on exact timing and placement of this cut-off low. The proximity of the trough and eventual cut-off low will mean higher than normal rain chances today through Sunday. The location of this upper level low also means we will be on the "backside" of the low. Models are indicating that dry air will be wrapping in on the west side of this upper level low and filtering in starting Sunday.
945 AM EDT Sat Oct 9 2021 A weakening upper low slowly approaching our region will bring some showers to far western New York today and tonight, with dry weather prevailing east of the Genesee Valley. A weak wave aloft and associated surface warm front will pass through the area on Sunday. At the same time, southeasterly onshore flow on the north side of low pressure moving up the Eastern Seaboard off the Delmarva will throw moisture back to the northwest across eastern PA and southcentral NY.
649 AM EDT Sat Oct 9 2021 A weakening upper low slowly approaching our region will bring some showers mainly to far western New York today and tonight. A weak wave aloft and associated surface warm front will pass through the area on Sunday. At the same time, southeasterly onshore flow on the north side of low pressure moving up the Eastern Seaboard off the Delmarva will throw moisture back to the northwest across eastern PA and southcentral NY.
This record heat is the result of continued building of the upper- level ridge and the low-level thermal ridge positioned overtop the region. Subsidence under the ridge will result in sunny skies and no precipitation. This will create very good downward vertical mixing of warmer air aloft and a slight westerly component of the wind may generate weak downslope warming. The low relative humidities and high winds may also create localized elevated fire danger for portions of the area. High temperatures should remain well above normal, but significantly cooler than Saturday.
Weak and drier high pressure at the surface for the next couple of days will keep lower end scattered rain chances. Weak high pressure will keep light E/NE winds in place across the waters through the period, with some drier air keeping low rain chances as well for the next couple of days.
With the lower stratus having sunk south into northern SD, this will also be something to watch.
957 AM CDT Sat Oct 9 2021 A broad sub-tropical ridge centered over the Rio Grande Valley this morning will continue to build eastward into the Southeast and TN Valley region today. The low-lvl divergence and lack of forcing will ensure dry conditions for today. Nevertheless, despite the thin veil of high clouds, mixing layer temperatures will be about 1-2C higher than yesterday, and temperatures should climb into the low/mid 80s at most locations. a little warmer than yesterday. The mid-level ridge becomes solidly entrenched over the Tennessee Valley Sunday, with heights topping out near 588 dam.
A weak coastal low pressure system may bring a few additional light showers to Northeast Pennsylvania and the Catskills late tonight and on Sunday. The upper level ridge have moved well east of the area. The weak surface front and upper level trough upstream in the western Great Lakes are making slow progress east. The trough is lifting to the northeast while the front is weakening. Late tonight into Sunday the upper level trough gets here while short waves are moving north ahead of a large coastal low. Temperatures now from the mid 50s to lower 60s will rise to the low 60s for the Catskills and Poconos to the mid and upper 60s for the rest of the area.
324 AM MDT Sat Oct 9 2021 Upper air analysis shows the upper trough over the western CONUS and SW flow aloft over the CWA. We can expect another band of precipitation later today on the backside of the low as it pushes through the region. This low pressure system is expected to strengthen also as it moves east of our region, creating a tightening gradient behind it and strong surface winds over the region tonight into Sunday.
In the wake of the trough feature which has passed over a portion of the area early today, precipitable water values range from around 1. Heavy rainfall is likely across the higher forecast coverage areas, with slower moving cells potentially bringing producing 2+" in a short period of time. West to NW winds of 10-15 knots this morning will veer more northerly into aftn with the passage of a frontal boundary and high pressure building across the northern Gulf of Mexico.
The next 24 hrs look dry and still unseasonably warm as upper ridging noses into the Ohio Valley from the SW and low-level southerly flow starts to set up. Not expecting enough coverage of dense fog for an advisory, but will likely cover the low vis with a Special Weather Statement.
422 PM EDT Sat Oct 9 2021 Upper air pattern consists of a trough in the upper Great Lakes region down onto the east coast, a ridge in the southern plains and a trough in the Rockies.
Showers and a few isolated thunderstorms will develop and lift northward across western and central North Dakota over the next several hours, with precipitation chances ending across the west later this evening as the upper low moves east and stalls over eastern North Dakota.
Given the low amounts of instability, large hail may be difficult to come by, but not entirely impossible.
Cold front will bring showers, MVFR/IFR conditions, mountain obscuration, and gusty W-NW surface winds.
409 PM EDT Sat Oct 9 2021 Building high pressure over northern Maine will maintain cooler temperatures across the region over the weekend with some gusty southerly winds. Strong high pressure anchored east of our region will help to keep us dry overnight. Temperatures on Sunday night will be a bit warmer than tonight with lows reaching the upper 40s to lower 50s.
First, a strong Pacific cold front/dryline pushes though Sunday evening, with strong west to northwest winds behind it.
Skies today will generally be partly cloudy with temperatures climbing into the low to mid 80s for the western 2/3rds of the area.
209 PM CDT Sat Oct 9 2021 The warm front has lifted north of the forecast area as of 19z. On Sunday despite the upper level ridge shifting off to our east taking the warmer 850mb temperatures with it, the day will start off a bit warmer which will jump start another possible record high temperature day for a number of locations. Unlike today, there will be less cloud cover on Sunday for a majority of the forecast area and surface winds will veer to the southwest and pickup ahead of a cold front due to deeper mixing. Thus high temperatures will be in the upper 80s to low 90s, with slightly cooler temperatures in the far northern portions of forecast area, closer to the cold front.
A modest increase in low level moisture, coupled with the high clouds holding temps down a few degrees, will likely keep RH values above critical levels.
Intrusion of dryer air in the wake of the frontal trough has allowed sfc dewpoints to slide into the upper 60s across northern sections this aftn. Ongoing fcst for Sunday keeps a unstable conds aloft as an elongated upr trough pivots across the Atlc waters and Fl peninsula during the day.
344 PM EDT Sat Oct 9 2021 High pressure to our east will maintain onshore flow through Sunday night with mostly cloudy skies, but generally dry weather.
A broad sub-tropical ridge centered over the Rio Grande Valley this morning will continue to build eastward into the Southeast and TN Valley region today. The low-lvl divergence and lack of forcing will ensure dry conditions for today. Nevertheless, despite the thin veil of high clouds, mixing layer temperatures will be about 1-2C higher than yesterday, and temperatures should climb into the low/mid 80s at most locations. a little warmer than yesterday. The mid-level ridge becomes solidly entrenched over the Tennessee Valley Sunday, with heights topping out near 588 dam.
Afternoon highs should reach into the mid to upper 80s, with a few of the typically warmer spots getting close to 90 degrees.
High pressure over the Midsouth will keep conditions warm and dry through the weekend. Upper level ridging is building into the Mid-South this morning. Upper level ridging will prevail with dry weather and above normal temperatures.
A cold front associated with the long wave trough will move through our area by mid-afternoon. Locations with the highest probability of measurable rain will be the Clearwater Mountains of Idaho and along US-12 up to Lolo Pass.
This will allow a cold front to slip south through the forecast area tonight ushering slightly cooler temperatures into the region for Sunday.
1047 AM MDT Sat Oct 9 2021 Upper air analysis shows the upper trough over the western CONUS and SW flow aloft over the CWA. We can expect another band of precipitation later today on the backside of the low as it pushes through the region. This low pressure system is expected to strengthen also as it moves east of our region, creating a tightening gradient behind it and strong surface winds over the region tonight into Sunday.
A pleasant fall day is expected tomorrow as a ridge slides east and high pressure dominates with sub-70 degree dewpoints locked in place.
Looking at the synoptic setup across the country, upper level water vapor imagery is showing an elongated trough extending from the Intermountain West to the central California coastline. Within a stream of moisture ahead of that trough, a thick batch of cirrus clouds had been in place over much of the CWA today. Surface obs at 20Z show a 1000 mb area of low pressure in central Nebraska and breezy southwesterly winds in eastern Kansas. Tonight, the western trough will split into two waves.
High pressure then brings dry, warm weather for Sunday into the work week. Tonight, the aforementioned high pressure will hold strong suppressing the formation of showers or storms. Temperatures will rebound into the low to mid 80s lowlands, ranging into the mid 60s northeast mountains.
144 PM CDT Sat Oct 9 2021 Upper ridging continues to build into the area this afternoon with just some scattered diurnal Cu noted on the plateau. Sunday will be a warm one as the upper ridge will be large and in charge.
These readings are 12-15 degrees above normal and only 3-4 degrees degrees below record highs which are in the low 90s.
VFR will prevail the rest of the day through most of tonight as high pressure builds in, but fog is a good bet again toward sunrise through mid morning on Sunday. Garuckas Chattanooga Airport, TN 61 83 63 82 65 / 0 0 0 10 10 Knoxville McGhee Tyson Airport, TN 58 81 60 81 63 / 0 0 0 10 10 Oak Ridge, TN 59 81 61 81 63 / 0 0 0 10 10 Tri Cities Airport, TN 56 80 55 81 58 / 0 0 0 0 10.
That said, a mostly cloudy sky has limited heating, with current temps ahead of the cold front in the mid 60s, to the low 70s.
344 PM CDT Sat Oct 9 2021 A lead short wave moving through SD this afternoon will send a cold front through wrn and ncntl Nebraska tonight. The temperature forecast tonight and Sunday leans on the short term model blend which is slightly warmer with lows and cooler with highs. Mixing associated with cold air advection tonight is the reasoning with the warmer lows. The short term model blend was only slightly cooler than the guidance blend for highs Sunday. The cooler guidance blend was the basis for lows in the 30s. The models continue to converge on the timing and track of a major fall cyclone.
Otherwise edge of moisture field from the low off the Carolina coast and upper wave axis could allow for some isolated convection in east central GA this afternoon and have already seen some isolated showers in recent radar scans. /Issued 410 AM EDT Sat Oct 9 2021/ Current surface analysis shows a low pressure system off the SE GA coast. Aloft, a longwave trough stretches from the central Great Lakes down to the SE GA coast. NListemaa Upper level pattern across the CONUS will be active through the upcoming week, but our local weather will once again be influenced heavily by a cut-off low.
Broad ridging over the eastern CONUS at all levels will ensue, aided by low pressure undergoing cyclogenesis in the central CONUS. Long range deterministic models indicate that the aforementioned low pressure in the central CONUS will travel northeasterly through the Midwest, and may provide a slight chance of precipitation midweek. Expect diminishment of the sct showers and alleviation of the MVFR to IFR st blanket as the upr trough ovr the Upr continues to fill late this aftn and into the eve.
Though we are running behind expected 80 degree temperatures in south central Nebraska especially, afternoon temperatures in the lower to middle 70s are still pretty nice. A much stronger push of northwest winds, dry air and cooler temperatures will come through during the overnight hours and clear most of the forecast area. That rain chance will be on the sharp northwest side of an upper low moving up and out of the Southern Plains.
Could again see some patchy fog from radiational cooling or some low stratocu developing near sunrise Sunday, but otherwise should be dry and mostly sunny thru the day Sunday as some subsidence/upper ridging sets in. Baker We remain sandwiched between a digging low over the western US and a closed low just off the eastern coast of Florida (that dropped out of the trough that brought our gratuitous rainfall over the past week) for the next several days. The presence of the low to our southeast helps preserve the location of the upper-level ridge that holds our dry airmass in place. As the low to our west lifts to the north and east across the Plains, the western portion of the CWA is clipped by a stalling cold front.
216 PM MDT Sat Oct 9 2021 Scattered showers and storms will continue this afternoon as northern stream upper low slowly pushes through the Northern Plains. Precipitation chances will wane late tonight into Sunday morning as northern upper low departs and the southern stream vort max begins to eject across the southern plains.
High clouds will increase across the north late tonight as cold, deep trough approaches the Pac NW. Only update for the forecast tonight is to remove mention of fog, otherwise looking ahead to the cold frontal passage late Sunday that will bring gusty winds and mountain snow.
This low will slowly track to the north northeast through the night.
845 PM EDT Sat Oct 9 2021 Upper level trough will move east of the area tonight and drier air will spread into the region. Although low pressure will develop along the North Carolina coast, a pressure ridge will dominate across the area and expect warm and mainly fair weather for the next few days. The atmosphere continues to slowly dry out as the upper low digs southeastward to a position off the northeast coast of Florida. Synoptic lift is also decreasing with the trof axis east of the area. Upper level trough along the eastern seaboard with anomalous low off the southeast coast of Florida. Upper level ridge from the western Gulf of Mexico northeast across the Tennessee Valley will build into the western and central Carolinas during the period. Pressure ridge across western Carolinas.
1007 PM EDT Sat Oct 9 2021 Satellite loop shows some mid and high cloud streaming into central Indiana on the leading edge of an upper ridge. Tempertures are in the lower 70s with dewpoints in the 60s and southeasterly winds around 4 to 8 mph.
An associated surface through lower level low sits near the Carolina Coast and extends a trough across Florida and reaching southwestward across the Keys. The combination of being near the trough axis and convective outflows has resulted in light to gentle but variable breezes. Short Term Update - The upper level trough will continue to mostly cut off from the westerlies further north while it nudges further out into the Atlantic through the overnight. The lower level low and associated trough will remain fairly stationary. Winds will remain variable due to the proximity of the trough axis. A trough associated with a low off the Carolina coast will result in light to gentle and variable winds across Keys waters through the overnight period.
Discussion: Upper ridging is slowly building into Tennessee with surface ridging. Surface ridging will keep winds generally light and less than 10kts. Chattanooga Airport, TN 63 83 63 81 66 / 0 0 0 0 10 Knoxville McGhee Tyson Airport, TN 60 82 60 82 63 / 0 0 0 0 10 Oak Ridge, TN 60 81 60 80 63 / 0 0 0 0 10 Tri Cities Airport, TN 55 79 55 80 58 / 20 0 0 0 10.
503 PM MDT Sat Oct 9 2021 Scattered showers and storms will continue this afternoon as northern stream upper low slowly pushes through the Northern Plains. Precipitation chances will wane late tonight into Sunday morning as northern upper low departs and the southern stream vort max begins to eject across the southern plains.
Broad ridging over the eastern CONUS at all levels will ensue, aided by low pressure undergoing cyclogenesis in the central CONUS. Long range deterministic models indicate that the aforementioned low pressure in the central CONUS will travel northeasterly through the Midwest, and may provide a slight chance of precipitation midweek. Expect diminishment of the sct showers and alleviation of the MVFR to IFR st blanket as the upr trough ovr the Upr continues to fill through the eve.
High pressure is in control of our weather which is leading to clear skies and cool weather. There is potential for some patchy fog in the Pine Belt tonight, which could extend across the Highway 84 corridor before daybreak.
954 PM CDT Sat Oct 9 2021 Midevening GOES IR imagery showed broken, partially opaque cirrus streaming southeast across the Midsouth, spilling over an upper ridge axis oriented along the MS River. 9 PM surface temps ran 0 to 2 degrees warmer than 24 hours previous. This ridge axis will drop southeast overnight, allowing partial clearing from the west. Despite this, the boundary layer should remain partially mixed, downstream of deep low pressure over the plains. These readings are 12-15 degrees above normal and only 3-4 degrees degrees below record highs which are in the low 90s.
647 PM CDT Sat Oct 9 2021 A lead short wave moving through SD this afternoon will send a cold front through wrn and ncntl Nebraska tonight. The temperature forecast tonight and Sunday leans on the short term model blend which is slightly warmer with lows and cooler with highs. Mixing associated with cold air advection tonight is the reasoning with the warmer lows. The short term model blend was only slightly cooler than the guidance blend for highs Sunday. The cooler guidance blend was the basis for lows in the 30s. The models continue to converge on the timing and track of a major fall cyclone.
A highly amplified mid-upper ridge over the eastern US will yield a dry and unseasonably warm period for the local area, while several powerful cyclones over the Plains are deflected poleward into Canada.
651 PM EDT Sat Oct 9 2021 High pressure brings dry weather with cool mornings and warm afternoons for Sunday into the work week. Tonight, the aforementioned high pressure will hold strong suppressing the formation of showers or storms. Temperatures will rebound into the low to mid 80s lowlands, ranging into the mid 60s northeast mountains.
Otherwise, cirrus clouds will continue spilling atop the upstream ridge (and move in from our northwest to southeast) as the downstream mid- and upper trough moves off to the east of the region.
658 PM CDT Sat Oct 9 2021 An upper low continues to churn over the Northern Plains, centered over central South Dakota. Showers and a few isolated thunderstorms will develop and lift northward across western and central North Dakota over the next several hours, with precipitation chances ending across the west later this evening as the upper low moves east and stalls over eastern North Dakota.
However, showers and isolated storms will continue offshore, as a low pressure system meanders off of the Southeast US.
922 PM EDT Sat Oct 9 2021 High pressure brings dry weather with cool mornings and warm afternoons for Sunday into the work week. Tonight, the aforementioned high pressure will hold strong suppressing the formation of showers or storms. Temperatures will rebound into the low to mid 80s lowlands, ranging into the mid 60s northeast mountains.
457 PM MDT Sat Oct 9 2021 Small area of lift behind the cold front in the dynamic flow of the upper level trough is generated a couple showers with isolated thunder. A cold front is currently progressing across the forecast area with gusty winds and cooler temperature behind it. The possibility of precipitation across the far southern portion of the forecast area has steadily migrated further south, nearly out of the area, from Sunday through Sunday evening as the upper trough sweeps across the High Plains region.
305 PM MDT Sat Oct 9 2021 A cold front is currently progressing across the forecast area with gusty winds and cooler temperature behind it. The possibility of precipitation across the far southern portion of the forecast area has steadily migrated further south, nearly out of the area, from Sunday through Sunday evening as the upper trough sweeps across the High Plains region.
Weak high pressure will build into the area tonight and Sunday and bring a quiet weather.
Upper ridging continues to build into the area this afternoon with just some scattered diurnal Cu noted on the plateau. Sunday will be a warm one as the upper ridge will be large and in charge.
812 PM EDT Sat Oct 9 2021 The upper level low pressure off the East Coast will continue to move east while its associated frontal boundary stretches across south Florida. High pressure will continue to dominate through the period, with light E/NE winds becoming west to northwesterly in the afternoon.
For a time later this morning, the pressure gradient is rather tight over northern SD and some of the hi-res wind output is indicating wind advisory speeds over the higher terrain of McPherson and Edmunds counties. Winds go fairly light, so we're setting the stage for some fairly chilly lows, although still above freezing.