Aikyam-Lab/Synoptic-Bench huggingface dataset:
Strong high pressure will bring warm and dry weather to northwest California this week. Strong ridging across the north eastern Pacific Ocean will bring abrupt warming and plummeting afternoon humidity today and Tuesday. Some patchy coastal and valley fog will will dissipate through the morning hours but the dry airmass in conjunction with a thermal trough over the coast will result in mostly clear skies. The thermal trough will also bring enhanced northeasterly winds the next several days. Mendocino County could see some breezy conditions this afternoon on ridgetops, however, the strongest 925mb winds look to be farther south across Lake, Napa, and Sonoma counties. Warm and dry weather will persist through the rest of the week, although, interior temperatures will gradually decrease as the upper ridge breaks down and 500mb heights fall.
Sfc lee trough will give way to a backdoor cold front across the ern plains aft 23/15Z with nely and ely wind shifts. Dry, fall weather is here to stay with a couple cold fronts forecast to push through. The first cold front, a backdoor front, will push down the Eastern Plains later today then progress west to near the Continental Divide tonight.
Strong winds will develop today as a cold front pushes through the region. A very powerful storm system will develop over the next 36 hours across the Great Lakes region as a broad upper level trough with a textbook PV signature merges with a cutoff low over the Tennessee River Valley.
Sharp cold frontal boundary now seen clearly on radar tracking southward across the Wyoming and Nebraska plains. Heights rise aloft on Tuesday as the jet core shifts east and ridging builds over the intermountain west.
Significant moistening of the lower levels will then begin in earnest. After passage, some of the coldest air of the season will dip down through the area behind a secondary trough. Temperatures for Tuesday afternoon will remain in the 50s as the coldest portion of the airmass will arrive mid-week behind this secondary trough. The period will be dominated by various iterations of a central/eastern CONUS large scale upper trough. As the period starts, a surface cold front will be pushing east of the Appalachians, and drier air should be in place locally in the wake of frontal precip.
The first day to really feel like fall was underway across Mid TN, At mid morning, a cold front and back edge of a band of rain was moving across the Plateau. This band will continue moving east, leaving Mid TN with cloudy skies and isolated to scattered light showers through mid afternoon as a mid level trough crosses the area.
Winds and temperatures will be the primary concern as a series of strong upper troughs move across the region during the period. The first trough was over the northern plains at 07Z with a cold front stretching from the eastern Dakotas across northern Nebraska. The upper trough will deepen and intensify this afternoon and tonight over the Great Lakes, then come together with the earlier system that moved through our region this past weekend on Tuesday over the northern Great Lakes.
Showers and isolated storms will gradually end from west to east today as the cold front moves across our area.
Presently, traces have been recorded at Chadron, Winner, Valentine, and Pine Ridge. Otherwise, cooler highs will prevail today compared to yesterday with cooler air aloft and cold air advection occurring at low-levels. Cooler lows prevail tonight compared to this morning with lows forecast around 30 to the upper 30s.
temps ranged from the 20s and 30s for the high valleys, 30s and 40s for the far eastern plains, to the 50s to around 60F for the I-25 corridor. An upper trough crossing the Dakotas has pushed a weak cold front down into Colorado overnight, and it is expected to cross the Palmer Divide by late morning. Again, this will be a dry cold front so no pcpn is forecast, but temps are expected to only climb into the 60s for most locations today.
Of course, it will take a few hours for the worst conditions to impact tri while cha will suffer the impacts this morning with improving weather behind the cold front toward mid day into the afternoon.
Right now Tuesday looks like it may be the hottest day but offshore winds may be slightly weaker, reducing adiabatic compression, however an overall warmer airmass may negate that impact.
Widespread showers and possibly a stray thunderstorm will continue over the region through much of the day as a cold front approaches the area. Chattanooga Airport, TN 68 48 63 41 / 100 10 0 0 Knoxville McGhee Tyson Airport, TN 68 48 61 40 / 90 10 10 10 Oak Ridge, TN 67 47 61 41 / 100 20 10 0 Tri Cities Airport, TN 68 46 61 36 / 100 60 20 10 TN.
629 AM CDT Mon Oct 23 2017 The cold front that brought a few light showers, and brief gusty winds, has shifted east of the area. Behind the exiting cold front, and as mixing increases, windy conditions will develop this morning, and continue through the afternoon hours, before diminishing around sunset. Grassland fire danger index will rise into the high to very high categories over the eastern two-thirds of the forecast area today as RH values fall to 25 to 40 percent. The lowest humidity is expected west of the Missouri River. We will be stuck between exiting/deepening low pressure setting up over the Great Lakes, and strong high pressure over the Pacific Northwest.
High pressure over the region will lead to well above normal temperatures areawide today.
855 AM MST Mon Oct 23 2017 Well above normal temperatures will persist the next several days as a strong area of high pressure prevails across the western states. This high pressure system will diminish throughout the week resulting in a gradual cooling trend, though temperatures will continue to remain above normal. Meanwhile, upstream East Pacific ridging will translate into near record temperatures over the Southwest and renewed Santa Ana concerns along coastal California. Latest operational models show the ridge building across the Great Basin Tuesday, which will produce a downslope flow and subsequent adiabatic warming during the afternoon across the lower deserts.
Strong high pressure will sit over the Pac NW this week, with dry and mild conditions.
Latest IR/VIS satellite shows some mid and high level clouds moving over top the ridge across southern Washington and far northeast Oregon this morning. The upper ridge continue to build and amplify overhead tonight into Tuesday. As the inversion gradually strengthens expect patchy fog to again develop in the lower valleys and basins late tonight /Tuesday morning.
Next front to move through the region later this work week, with considerably cooler temps to settle in behind the boundary.
A slow moving frontal boundary and secondary low pressure system will move through the area today, followed by a large upper level low tonight into Tuesday night. This will provide ample opportunity for widespread rainfall and a turn toward much cooler temperatures. Another frontal system and reinforcing shot of cooler air will come late in the week, bringing additional chances for precipitation and continued cool conditions. Showers associated with this upper level low will be a threat across the area into Tuesday night.
Only change to the forecast this morning was to lower hourly and afternoon temperatures slightly in response to cooler observed temperatures this morning.
647 AM CDT Mon Oct 23 2017 Most of the low temperatures overnight took place before the frontal passage and in some cases that means the low was before or shortly after midnight. Temperatures in many places have jumped up by around 15 degrees in these pre-dawn hours with mixing behind the cold frontal passage. We expect cold air advection and strong winds across the entire area today behind a cold front. Despite the cold air advection, strong mixing will allow highs to climb close to where they were yesterday or generally about 5 degrees cooler than yesterday on average.
Some patchy dense fog may be possible this morning before southwesterly winds become breezy by mid morning today ahead of a dry cold front approaching the region. The low level thermal ridge will nose east over the region today ahead of a cold front. With the cooler low level temps not expected to arrive until closer to 00z, there may be enough time to warm up above consensus guidance and the forecast will lean that way. Winds aloft will increase considerably overhead as the upper jet dives south over the region on the back side of an amplifying upper trough over the Great Lakes and Mississippi valley.
A cold front will move across the area between 06Z and 12Z tonight and Tuesday morning.
This trend should persist this afternoon and allow for greater mixing and gusty winds in southeast Wyoming Have been pondering on issuing a high wind warning for the Nebraska Panhandle this afternoon, but the low level water vapor loop is not depicting that strong of elevated mixed layer yet. Sharp cold frontal boundary now seen clearly on radar tracking southward across the Wyoming and Nebraska plains. Heights rise aloft on Tuesday as the jet core shifts east and ridging builds over the intermountain west.
Mostly clear skies and dry conditions are expected today as the upper trough pushes east out of the region and an upper level ridge moves in to replace it by Tuesday. Hickford An upper level ridge positioned over the western U. Lighter winds are expected on Tuesday as the upstream ridge advances and extends further into eastern Montana. Expect warmer temperatures on Tuesday with the associated height rises as well.
A weak cold front will move through the area this afternoon. The region will be under the influence of dry northwest flow aloft, as a deepening trough over the Mississippi River valley remains to our northeast. At the surface, an exiting high pressure system will keep the region under weak southerly flow throughout the day. A weak cold front will move through the area by mid afternoon, beginning in the Big Country, then moving to the south and east.
A dry and stable airmass is in place behind the cold front. /issued 345 AM CDT Mon Oct 23 2017/ A much quieter morning this morning with the cold front that triggered yesterday's weather currently along a Birmingham to Pensacola line. Upper low is near Memphis at this time. Some low clouds wrapping around upper low are noted on satellite over Mississippi, but most of the area is clear. Upper pattern is in the process of digging a deep trough into the eastern third of the country. We should see abundant sunshine across the area today with cooler temperatures than earlier in the weekend. Highs on Tuesday likely to be a few degrees cooler than today, but with the frontal passage, late afternoon and early evening temperatures could drop pretty quickly.
Strong winds never developed down toward Sheridan tonight, despite the subsidence and strong flow aloft, so have cancelled the remainder of the High Wind Warnings. Temps will be cooler than yesterday. Building heights associated with ridge axis to our west will bring dry and warmer conditions Tuesday. Lee side surface trof will deepen Tuesday night as a clipper system drops through western Canada.
and do expect the passage of a pre-frontal trough by 12z this morning to allow for a shift in the winds to a more northwesterly regime. the midday timeframe will mark the return of another round of cooler air into the area.
614 AM CDT Mon Oct 23 2017 An upper level low was essentially parked over SC Missouri and NC Arkansas this morning. A very sharp clearing line near US Highway 65 will slowly move east this morning as the upper low begins its slow departure. As slow as this low is moving it may take much of the morning to clear out in the Eastern Ozarks. Winds will begin to increase and veer to the west and southwest Today ahead of an approaching cold front. The dry cold front looks to come through during the afternoon. Issued at 215 CDT Mon Oct 23 2017 The overall synoptic pattern the rest of the week into the weekend is a dry northwest flow with upper level troughs moving through every few days.
High pressure will build then remain over the western U. Latest model guidance is coming into better agreement later in the week with a trough diving southeastward toward the region. The ECMWF has trended towards both the GFS and GEM with tracking the trough farther to the northeast with less of an impact on northern Arizona.
Generally weak to moderate NE to SE flow across South Texas this morning/afternoon, then weak/moderate generally E flow early evening, followed by light/variable tonight in advance of a cold front tonight.
945 AM EDT Mon Oct 23 2017 High pressure will continue to move east of the region today.
Water Vapor satellite trends this morning place an upper level low near the Tennessee/Alabama border. /issued 415 AM CDT Mon Oct 23 2017/ Early morning GOES water vapor imagery showed an upper low over the Midsouth, lifting slowly east. The upper low and associated clouds will lift out this afternoon, in time for the arrival of a reinforcing push of drier and cooler air this evening. This evening's cold frontal passage will occur as deep midlevel height falls occur, leading to the formation of a longwave trof over the eastern half of the U.
/Issued 340 AM CDT Mon Oct 23 2017/ A cold front expected later this morning will keep the Panhandles cool through midweek.
Otherwise, 50s to the lower 60s for highs are on track. The cold front that brought a few light showers, and brief gusty winds, has shifted east of the area. Behind the exiting cold front, and as mixing increases, windy conditions will develop this morning, and continue through the afternoon hours, before diminishing around sunset. Grassland fire danger index will rise into the high to very high categories over the eastern two-thirds of the forecast area today as RH values fall to 25 to 40 percent. The lowest humidity is expected west of the Missouri River. We will be stuck between exiting/deepening low pressure setting up over the Great Lakes, and strong high pressure over the Pacific Northwest.
Temps will rise a few degrees into the low 50s but overall blustery and cool conditions will be seen today.
Amplifying upper ridge will keep conditions dry over the next couple days.
728 AM EDT Mon Oct 23 2017 High pressure will continue to move east of the region through Today.
1222 PM EDT Mon Oct 23 2017 High pressure will continue to move east of the region today.
Strong storms are unlikely thru this afternoon but a more organized band of storms along or just ahead of the cold front should push E/SE across north FL late in the day, extending SW into the eastern Gulf.
Temperatures behind this boundary are warmer than pre-frontal due to mixing and some downslope component. The pressure gradient will increase overnight as well as a strong area of low pressure rapidly deepens over Michigan.
Strong high pressure, surface and aloft, the next several days with dry weather and clear skies. Amplifying high pressure expected over the region today, with generally dry and warming conditions. High pressure remains over the area through Tuesday continuing the warming trend and allowing temperatures to reach right around, or just above normal values.
205 PM MDT Tue Sep 5 2017 Water vapor shows strong trof over the Upper Midwest/Great Lakes with strong NW/N flow through the Northern Plains. Upper ridge shifting slowly eastward across the western US. At the surface, ridge is building into the western Dakotas. This will result in quite a bit of freezing temps in the Black Hills, with some spotty freezing temps in far southwestern SD.
249 PM EDT Tue Sep 5 2017 Showers and thunderstorms will continue today as a cold front slowly moves across the region.
A strong cold front near the Ohio river will push se across KY/TN this morning, with breezy nw winds ushering in drier and cooler air into central and southeast IL today. A strong 541 dm 500 mb low over James Bay Canada has a strong upper level trof digging southward into the upper MS river valley and western Great Lakes today. Highs in the low to mid 70s, with Lawrenceville the warm spot near 77F. NW winds gusting 20-30 mph will make it feel cooler. A deep upper level trof over the Great Lakes and into the OH/TN river valley on Wed will continue the fall like weather over central IL. Upper level trof starts to pull slowly away from IL on Thu as it moves into the eastern Great Lakes region by sunset Thu.
1251 PM CDT Tue Sep 5 2017 Northwest winds in the wake of the cold front along with dewpoints in the low/mid 40s have prohibited fog formation overnight, despite clear skies and recent rainfall. The deep trough that is over us this morning will continue slowly sliding east this week and will be over the Canadian Maritimes this weekend. In it's wake, ridging moves in from the west, with the upper jet getting forced up to nearly the Canadian Arctic. We still have some pops lingering Wednesday out in Ladysmith and Eau Claire as they will still be under the influence of cyclonic flow with the upper low.
1145 AM MDT Tue Sep 5 2017 130kt upper jet seen clearly on GOES-16 WV imagery this morning over central Canada and the northern Great Plains will continue to dive southward today, digging out a highly amplified trough over the Mississippi Valley. Heights aloft begin to rise on Wednesday as the strong upper ridge over the western CONUS begins to shift east. Continued sunny skies with temperatures around 5 degrees warmer than today. The models are in pretty good agreement in showing the upper level ridge dominating the weather pattern through the weekend.
537 PM EDT Tue Sep 5 2017 A cold front will progress very slowly across the region this evening and practically stall overhead tonight.
/issued 1115 AM CDT Tue Sep 5 2017/ A cold front stretches from Camden TN to Tunica MS this morning. /issued 352 AM CDT Tue Sep 5 2017/ An unusually strong upper level trough was digging across the central U. this morning and will help to advance a cold front across the Mid South today. Canadian high pressure will build across the Mid South from mid week through the weekend.
Partly to mostly cloudy skies are in place across the region with temperatures in the lower 90s. The cold front associated with a large trough east of the plains is located to our north but a pre-frontal wind shift is already knocking on the door of the northern Hill Country. Additional chances for showers and storms will be possible overnight as the main cold front moves through the area. Overall, chances of precip will remain low due to lack of forcing as the main trough remains well to the east. Dewpoints in the 40s and 50s will allow for this cooler night time temperatures.
134 PM EDT Tue Sep 5 2017 Water vapor loop and RAP analysis shows a broad mid-upper level trough deepening over the Upper Great Lakes this morning. This trough is expected to remain entrenched over the Upper Great Lakes into midweek resulting in periods of scattered showers and cooler than normal temps. With all the clouds and showers and flow off Lk Superior temps will struggle to reach the lower 50s inland west to the low to mid 50s elsewhere closer to Lk Superior.
A deep mid/upper trough will continue to progress across the eastern half of the country the next few day, driving cool Canadian high pressure south across the Heartland of America.
315 PM CDT Tue Sep 5 2017 255 PM CDT Unseasonably cool weather will continue through tomorrow and beyond as a deep upper trough slowly moves across the upper midwest and Great Lakes regions. Any showers and much of the cloud cover will dissipate with sunset and temperatures should drop into the 40s across much of the CWA away from the Chicago metro urban heat island, where lows should remain in the lower 50s. Temperatures Wednesday should be even lower than Tuesday, with highs only in the lower to middle 60s. 315 PM CDT The deep trough responsible for the cool weather to start the period (highs in 60s and lows in 40s for many areas) will exit east by the weekend, enabling moderation in high temperatures back to near/around normal for early to mid September.
322 PM CDT Tue Sep 5 2017 Primary forecast focus is on cooler weather and low precipitation chances at times, in northern Oklahoma late week through the weekend. This afternoon, cooler, more pleasant temperatures have spread across the region behind the passage of the cold front.
304 PM MDT Tue Sep 5 2017 Cool stable post frontal airmass has settled in across the plains where highs have slowly climbed into the lower 70s which is around 15 to 20 degrees cooler than this time yesterday.
413 PM EDT Tue Sep 5 2017 Showery weather and well below normal temperatures can be expected through the week until high pressure returns this weekend. Quick update to handle a line of showers ahead of the approaching midlevel trough, also aided by differential heating. Otherwise, a few showers will continue over the ridges into the night, while other regions dry out and likely fog up.
126 PM EDT Tue Sep 5 2017 Much cooler conditions are expected today with highs generally in the upper 60s to near 70. A few light rain showers are possible during the day but much better chances for rain are expected overnight into Wednesday with the highest chances near Lake Michigan.
1234 PM CDT Tue Sep 5 2017 VFR until the cold front moves into and through Southeast Texas late tonight through tomorrow morning and shifts winds to the N and NE. The best dynamics will be right along this cold front itself and only expecting rainfall totals from one quarter to one half inch at this time. A much cooler/drier airmass to settle across SE TX in the wake of this front through the rest of the week. 41 The light onshore winds will continue today before the cold front arrives early Wednesday morning.
307 PM CDT Tue Sep 5 2017 Highly amplified upper flow with a deep trough in place across the western Great Lakes. to the vicinity of the trough axis. With the much cooler airmass in place, clearing skies and light winds overnight, expect lows in the low to mid 40s for most of the area, but even a few temps hitting the upper 30s are possible.
Upper level ridge axis will continue to build east over the Northern Rockies through the day today. Otherwise, high temperatures today are expected to climb into the mid to upper 70s across North Central Montana, with the low 80s expected across Southwest Montana.
143 PM EDT Tue Sep 5 2017 Moisture will begin to increase today ahead of an approaching cold front today.
215 PM CDT Tue Sep 5 2017 The cold front that passed through the area last night has moved south into Arkansas taking the elevated smoke with it and allowing a cooler airmass to move into place today. This cooler airmass will result in below average temperatures for the rest of the week as Wednesday being the coldest day with lows in the mid to upper 40s and highs barely making it into the 70s. High pressure and ridging building into the region will keep the area precipitation free at least through the work week.
247 PM EDT Tue Sep 5 2017 Showery weather and well below normal temperatures can be expected through the week until high pressure returns this weekend. An upper trough will continue to deepen over the region overnight. Dry conditions can be expected other than possible scattered rain showers over the ridges.
Persistent upper level ridging over the western U. By the end of the week, the upper ridge will weaken slightly as mid-level moisture is forecast to increase over the desert Southwest.
Dry conditions and a warming trend can be expected through the short term period with upper level ridging building into the region. Ridging will build back into the region starting Wednesday, and remain in control for the remainder of the period.
Low lying areas will feel the affect of that with lows dipping into the lower 40s, with mid to upper 40s elsewhere.