Aikyam-Lab/Synoptic-Bench huggingface dataset:
Today is a transitional day as a mid to upper level trough centered over Louisiana continues to push further east. Don't worry, relief is still in sight as a cold front approaches on Tuesday. Temperatures will still reach the low to mid 90s on Tuesday, but behind the front dewpoints will quickly drop into the upper 40s and 50s.
717 AM EDT Mon Sep 20 2021 High pressure at the surface and aloft will result in low humidity and dry weather today. By the middle of the upcoming week, a strong cold front and sharpening trough aloft will bring a widespread soaking rain to Pennsylvania. Following the frontal passage towards the end of the week, temperatures will be noticeably cooler for the first few days of fall. The clouds will be thickest over the Ridge-and-Valley region/central mtns. There will probably be patchy drizzle where the orographic lift is best (windward slopes/ridges), but enough mixing should occur Tues to poke some holes. The trough will deepen over the midwest which will be the primary weather producer for the middle and end of the week.
538 AM MDT Mon Sep 20 2021 Water vapor shows deep upper trof over the Northern Rockies/Northern Plains. At the surface, cold front is well east of our zones, with some gusty winds across south central SD early this morning. The rest of the week and weekend will be dry and warmer with generally west/northwest flow aloft.
251 AM PDT Mon Sep 20 2021 After a cool, wet, and breezy weekend, the Inland Northwest will become warmer and drier. Monday will be cooler than average with high temperatures mainly in the 60s. High pressure will build back into the region through Tuesday, and daytime temps will be about 6-11 degrees warmer than today.
The next threat in the forecast comes in the form of a cold front that is expected to move through the Mid South Tuesday night.
614 AM CDT Mon Sep 20 2021 H5 trof and embedded energy will lift northeast across the area today, with scattered showers and a few thunderstorms anticipated, especially east of the MS River. The chance of showers and maybe a rumble of thunder will continue behind the surface front Tuesday night as the parent upper trof moves toward the area from the west.
KBYX radar is detecting isolated showers in the vicinity of the Lower and Middle Keys, with scattered coverage off the Upper Keys in eastern Hawk Channel and the Straits of Florida associated with a weak area of directional convergence. With the 12z sounding at KEY continuing to reveal a moisture-rich environment and steep low level lapse rates, a cloud line is expected to form yet again today along portions of the Lower and Middle Keys.
This activity is occurring in deep southerly flow throughout the troposphere out ahead of an upper trough axis along the Mississippi River. As the trough moves across the area today, showers and possibly a few thunderstorms should become fairly widespread this morning then gradually diminish from west to east during the afternoon. However, our area remains in convergent flow between the upper trough to the west and high pressure off to our east, and the atmosphere is still very moist with PWATs around the 2 inch mark. Our forecast area will get a welcome break in the rainfall tonight into Tuesday morning as the upper trough axis lifts off to the east.
A cold front will impact the NE OK sites later in the period with a wind shift to the north between 00z-02z, and at the remaining sites through 06z. Another unseasonably hot day expected ahead of the much anticipated cold front which will move into northeast Oklahoma by late afternoon. As mentioned previously, areas with ongoing drought conditions/cured fine fuels will likely see the highest fire weather concerns. Still expect showers with embedded thunderstorms to increase in coverage behind the front as stronger forcing develops in association with upper trough axis. Finally a break in the heat with significantly cooler conditions expected behind the cold front with breezy north winds.
By midweek increasing high pressure across the the region will allow for a slight warming trend but with continued dry conditions. Mesoanalysis this morning shows an upper level trough moving through the Great Basin, with the tail end brushing northern Arizona. This trough will do little for the sensible weather across the state, but could induce a few mid level clouds. Somewhat higher moisture values are noted over southeastern Arizona, but with west to southwest flow in the wake of the glancing trough this moisture will stay removed from the CWA.
646 AM MDT Mon Sep 20 2021 A band of showers along w/ a few embedded thunderstorms associated with the 700 hpa cold front is expected to continue progressing to the east across the western Neb Panhandle over the next few hours, likely exiting the CWA around 12z. Freezing temperatures will be most likely in our zones along/west of the Laramie Range, but we have trended up-ward slightly with overnight lows given greater boundary layer moisture in place.
Lows tonight will be in the lower 70s inland with mid 70s at the immediate coast.
Tonight should be dry until near daybreak Tuesday morning when convection developing on the approaching cold front will attempt to move into the area. The cold front will enter the area 12Z to 15Z and will exit the area by 23Z. The upper trough will be getting better organized as it begins to impact the area in the late afternoon.
The upper trough continues to lift out of the area as a stronger trough and surface cold front moves out of the upper midwest Tuesday night.
Weak high pressure remains across the area with a weak easterly flow with sea breeze dominating the convection this afternoon and evening. Overnight, showers and storms will shift to over the local South Florida waters A similar pattern for Tuesday with high pressure, abundant moisture and weak easterly steering flow. Heavy rainfall leading to potential localized flooding continues to be the primary concern with the high moisture content leading to efficient and high rainfall rates. Moisture remains over the region as the amplified mid-level trough digs into the eastern third of the United States mid-week. High pressure, light flow and fairly benign marine conditons outside of convection.
Discussion So far today has been on the warmer side again with southwest winds gusting up to 25 mph. The well advertised cold front has started moving through the area, currently stretching from Nodaway County, MO to Doniphan County, KS. A deep upper level trough is also moving overhead, generating around 30-35 kts of deep layer shear in the same area. High pressure and beautiful fall weather will follow the cold front.
221 PM CDT Mon Sep 20 2021 At 120 PM a cold front was along a line from Clovis to Petersburg to Paducah. The pre-frontal trough looks to have stalled as surface winds at Aspermont and locations to the east have now backed toward south. Cold advection behind the front will bring our first day with a cooler than normal average temperature at Lubbock since August 29th. The main story for the middle of this week will be a pleasant glimpse of fall-like weather conditions as we remain under northwesterly flow aloft with slowly building upper level ridging to our west.
5km) suggest potential window for convection to tap into orthogonal orientation to the line/cold front. Inverted V profiles ahead become less important considering the forcing mechanism, but while deep shear is not well oriented for a widespread/high confidence wind or QLCS tornado threat, the low level winds (0-1. A subsequent upper low is then anticipated to move down from the Canadian Plains and into the Upper Midwest/Great Lakes late week into the weekend. A few recent runs have suggested an outside shot at some light precipitation as a weak cold front slides through, but is likely to struggle to produce anything with a quite dry air mass in place.
223 PM MDT Mon Sep 20 2021 Mean ridging can be expected through most of the period, although an increasingly active northern stream will support periodic cold fronts into the region, the next being Thurs. Upper level trough and associated cold pool will continue to support sct to isold showers into the evening, being heavily diurnally driven. The next cold front will arrive Thurs with cooler and breezy conds Fri.
Cold front continues to push into southern TX this evening. Secondary push of cooler air expected later tonight with morning lows expected to be in the 50s across the Panhandles. However, there seems to be enough dry air in the lower levels and the 500mb warm nose appears to cap off any instability that was previously forecast. But again, the lower levels look pretty dry and not sure there will be enough moisture overcome the dryness in the lower levels. Highs on Tuesday are expected to be on the cool side with most of the Panhandles being in the lower to mid 70s. Normal highs for this time of year are in the lower to mid 80s. High pressure will build over the western CONUS as the upper level trough begins to slide east out of TX Tuesday evening.
The better chance for precipitation comes tonight as a cold front will help usher in a line of thunderstorms. High temperatures will be in the low to mid 80s today, dropping to the low to mid 70s for Tuesday. Greater rainfall amounts are still forecast area- wide in association with the cold front forecast to move through central Illinois from late tonight through Tuesday. At the surface, high pressure exists over New England and low pressure over the central U. However, the better chance for showers and thunderstorms will come late tonight and early Tuesday morning as a cold front associated with the approaching upper wave pushes southeast across the region.
Breezy winds expected this morning as an incoming upper level ridge builds in from the southwest. Gusts of 20-25 mph will be possible through the Lower Columbia Basin this morning before subsiding through the evening hours.
KS Chattanooga Airport, TN 69 81 65 74 53 / 50 60 70 70 10 Knoxville McGhee Tyson Airport, TN 67 81 66 76 53 / 60 60 70 70 30 Oak Ridge, TN 67 81 65 74 52 / 50 70 70 70 20 Tri Cities Airport, TN 65 77 64 78 52 / 60 60 70 80 50 TN.
Behind a cold front that is now through the CWA, strong north winds and cooler temperatures are expected for the short term period. This will relax towards sunset as high pressure builds in from the northwest to 15-25 mph. 10-20 mph winds expected Tuesday as the gradient is much more relaxed as the aforementioned front is further to the southeast and high pressure takes over southwest Kansas. Overnight lows will be quite chilly after the recent warmth dropping to the low to mid 50s with strong radiational cooling. A relatively tranquil pattern is forecast through the end of the week as a much drier air mass overspreads the Western High Plains in conjunction with ridging aloft building in across the Central and Southern Rockies.
A trough of low pressure will extend from the central gulf coast region, east across the area this period, with high pressure centered well to the northeast. Ample moisture will remain in this trough, leading to continued rounds of showers and thunderstorms. Lows in the lower 70s Tonight, with highs in the middle 80s Tuesday.
A ridge of high pressure will build into the area on Tuesday providing sunshine, dry conditions and some increase in temperatures for at least a couple of days. An area of low pressure will move into the region later this week and linger through the weekend. Discussion The primary weather of note today has been some cooler temperatures and gusty north winds, especially down the Colorado River Valley. Temperatures in many locations are 5 to 10 degrees cooler at noon today than they were yesterday at the same time.
It doesn't look like coverage and intensity will be like what we have seen the last couple of days until the evening hours when a cold front approaches the area.
Today will be the hottest of the last several days as southerly winds pick up ahead of an approaching cold front set to move through the region this evening and tonight. highs will mainly be in the lower to mid 90s. A nice Fall cold front is still on track to move through the area brings some cooler air to the region for the next several days.
Much cooler fall-like weather is expected Tuesday with some lingering showers over southern MO, especially in the morning.
/issued 353 AM CDT Mon Sep 20 2021/ A weakening trough axis remains across Arkansas and Louisiana this morning. A deepening upper trough extended from the Canadian Prairie Provinces southward to the Four Corners area. At the surface, low pressure and an associated cold front extended from western Ontario Canada southwestward to Colorado. Temperatures and dew points were in the low and mid 70s.
A cloud line fired earlier along portions of the Lower Keys late this morning, but soon fizzled out. This directional convergence and ample available solar insolation has allowed a second cloud line to form over the Lower Keys, and KBYX radar trends seem to indicate increasing coverage.
Prior to this, we'll see a warming trend as upper ridge migrates from the north and central Rockies. It is a challenge trying to forecast the low ceilings out there early this afternoon.
This all along and south of the strong cold front as compressional heating boosts temperatures. Much cooler tomorrow, generally in the upper 70s to lower 80s.
1121 AM MDT Mon Sep 20 2021 Water vapor shows deep upper trof over the Northern Rockies/Northern Plains. At the surface, cold front is well east of our zones, with some gusty winds across south central SD early this morning. The rest of the week and weekend will be dry and warmer with generally west/northwest flow aloft.
This unstable airmass will be pushed southeast away from our CWA tonight by a cooler more stable air mass tonight.
Moisture will continue to increase Tuesday ahead of an approaching cold front. The cold front, increased moisture, and sufficient instability will lead to widespread convection ahead of and along the cold front Tuesday afternoon/evening.
251 PM CDT Mon Sep 20 2021 Light rain continues in the leading edge of the upper trough this afternoon. In the back edge of the trough, there is greater instability and scattered thunderstorms have developed on the northwest flow across western SD. The moderating factors will be southerly low level winds as the high exits and an upper ridge building in.
While the cold front has pushed eastward out of our area, a fairly expansive stratus deck still remains overhead.
A ridge of high pressure will build into the area on Tuesday providing sunshine, dry conditions and some increase in temperatures for at least a couple of days. An area of low pressure will move into the region later this week and linger through the weekend. The primary weather of note today has been some cooler temperatures and gusty north winds, especially down the Colorado River Valley. Temperatures in many locations are 5 to 10 degrees cooler at noon today than they were yesterday at the same time.
a cold front will drop SE into the state. Aloft, phasing of the closed upper low with an approaching trough will commence today as the trough ejects into the Plains from the Rockies. At the surface, high pressure will remain to the E of the state resulting in S/SWrly winds this afternoon. On Tuesday, the aforementioned trough will approach the state from the N as a surface cold front sweeps across AR. Showers and thunderstorms are expected to develop invof of the cold front, with better coverage over the Nrn half of the state. Much drier and colder air will advect into the region Tuesday Night and as a result, lows should dip into the low 50s N to the near 60 over the S.
H5 trof and embedded energy will lift northeast across the area today, with scattered showers and a few thunderstorms anticipated, especially east of the MS River. The chance of showers and maybe a rumble of thunder will continue behind the surface front Tuesday night as the parent upper trof moves toward the area from the west.
High pressure builds over the cntrl Rockies/High Plains tonight, which should maintain steady but weakening northwesterly flow across the area. As the center of high pressure slides ewd toward the NE panhandle late in the overnight period, could see a brief period of relatively calm conditions, allowing lows to drop into the upper 30s for some. Mild aftn temps tomorrow as mid/upper trof shifts ewd and high pressure slides east thru the area.
Temperatures tonight plummet into the 20s and 30s with widespread areas of frost and freezing temperatures expected, especially along and west of the Laramie Range, warranting a Freeze Warning and Frost Advisory. Tuesday, the warming and drying pattern comes back with the ridge positioning itself over the area.
Clearing skies and a colder air-mass will result in widespread low temperatures in the lower to mid 30s. The rest of this week into the weekend will be dry and warmer as the Northern Rockies will be under the influence of high pressure most of the week.
Warmer and drier conditions are expected toward mid-week. MORNING DISCUSSION: Synoptic Setup: As of early this morning, a large trough runs down the High Plains of Alberta, Montana, and Wyoming. To the west a large ridge is developing just off the coast of the Pacific Northwest and British Columbia. Behind this another trough/ridge couplet is developing over the Gulf of Alaska and farther toward the west in a very progressive fall pattern. Today into Tonight: Convection will develop on the backside of the trough across our southwestern zones NAM forecast soundings are showing CAPE around 300-600 with some of it rising above 20*C for possible light lightning.
1055 AM PDT Mon Sep 20 2021 After a cool, wet, and breezy weekend, the Inland Northwest will become warmer and drier. Monday will be cooler than average with high temperatures mainly in the 60s. High pressure will build back into the region through Tuesday, and daytime temps will be about 6-11 degrees warmer than today.
227 PM CDT Mon Sep 20 2021 Cooler temperatures and a chance for showers and thunderstorms in the southwest this afternoon and evening highlights the short term forecast. Light rain showers in the wake of a cold front were finally exiting the eastern James River Valley early this afternoon. Expect partly cloudy skies and highs in the lower 60s to around 70, with a slight breeze. Upper level flow will become marginally amplified over the Northern Plains midweek in response to deepening troughs both upstream off the coast of the Pacific NW and downstream over the Ohio Valley.
As high pressure then settles in across the area on Tuesday. This high will then keep winds to a minimum Tuesday night.
1050 AM PDT Mon Sep 20 2021 Much warmer weather is in store for Central California Tuesday. High temperatures Tuesday afternoon will be around ten degrees warmer than this afternoon.
254 PM CDT Mon Sep 20 2021 Today/Tonight: Upper trough continues to approach the region, with an associated surface cold front already moving through the forecast area. Despite some clouds, lows should drop into the 50s as cooler and drier air continues to filter in.
Behind a cold front that is now through the CWA, strong north winds and cooler temperatures are expected for the short term period. This will relax towards sunset as high pressure builds in from the northwest to 15-25 mph. 10-20 mph winds expected Tuesday as the gradient is much more relaxed as the aforementioned front is further to the southeast and high pressure takes over southwest Kansas. Overnight lows will be quite chilly after the recent warmth dropping to the low to mid 50s with strong radiational cooling. Longwave pattern sets up another upper level ridge across much of the western states and Rockies giving way to quiet northwest flow for the high plains. Return of southerly flow and a leeside trough over eastern Colorado will give way to south winds becoming gusty late week.
This all along and south of the strong cold front as compressional heating boosts temperatures. Much cooler tomorrow, generally in the upper 70s to lower 80s. Temperatures will be much cooler, with overnight lows ranging from the lower 50s across the Big Country, to mid to upper 50s along the I-10 corridor.
SHORT TERM (Tonight through Tuesday Night): A cold front continues to plunge south toward Deep South Texas as a 500mb trough swings across the Plains. The pressure gradient strengthens along the lower Texas coast into tonight before weakening into Tuesday afternoon, keeping southeasterly winds a little breezy into this evening, especially along the coast.
321 PM EDT Mon Sep 20 2021 Weak ridging aloft tonight will be replaced by a trough moving into the eastern U. For the rest of today we'll continue to see scattered to numerous showers and thunderstorms with the highest chances over the interior and inland southwest Florida.
219 PM MDT Mon Sep 20 2021 A deep trough extends into Colorado with a 100kt jet diving down into the base of the trough. Current satellite imagery shows some cu development over the higher terrain and Palmer Divide with SPC mesoanalysis currently showing up to a 1000 J/kg of MU CAPE over the region. This will allow for temperatures to remain on the cooler side with continued subsidence bringing mostly sunny skies. Highs will once again feel fall-like in the upper 60s across the plains and 40s to 50s over much of the high country for Tuesday with conditions remaining dry. There is general agreement among ensemble guidance that Colorado will be under a ridging regime for most of the period.
It still appears there is some potential for a few storms to develop along a cold front late this afternoon (~5 pm) through the early evening hours (~7-8 pm). As a trough approaches and moves across the region late tonight into early Tuesday, better forcing should support higher chances across the northern half of Oklahoma.
A band of showers along w/ a few embedded thunderstorms associated with the 700 hpa cold front is expected to continue progressing to the east across the western Neb Panhandle over the next few hours, likely exiting the CWA around 12z. Freezing temperatures will be most likely in our zones along/west of the Laramie Range, but we have trended up-ward slightly with overnight lows given greater boundary layer moisture in place.
205 PM CDT Mon Sep 20 2021 The main forecast concerns are all bunched together in the first 24 hours of the forecast, associated with the first strong cold front of the season that is knocking on our doorstep at the moment. The high instability will lead to the potential for an isolated severe storm or two, with damaging downburst winds being the main concern given the high DCAPEs and favorable forecast soundings.
Temperatures will continue to be seasonable, with highs in the upper 80s to around 90 degrees, with lows in the low to mid 70s.
1239 PM CDT Mon Sep 20 2021 A strong cold front has moved through most of the area overnight with much cooler air now in place. The mid level trough and upper level trough are a bit slow to move east of the area, so the chances for showers and isolated thunderstorms will linger into the early evening, although by late afternoon the activity should be more isolated to scattered. As for temperatures, much cooler than yesterday with highs in the 60s, maybe some lower 70s in northwest IA this morning before falling during the day.
Overnight lows will mainly be in the lower 70s. Scattered to numerous showers and storms will be possible on Tuesday as moisture increases out ahead of an approaching cold front.
/Tonight through Tuesday Night/ The main synoptic feature impacting the short-term period will be a cold front that will move across the region on Tuesday. Overnight low temperatures forecast to fall into the lower 70s tonight.
Biggest aviation concern for this period will be the passage of a cold front this evening and overnight. Today will be the hottest of the last several days as southerly winds pick up ahead of an approaching cold front set to move through the region this evening and tonight. highs will mainly be in the lower to mid 90s. A nice Fall cold front is still on track to move through the area brings some cooler air to the region for the next several days.