Aikyam-Lab/Synoptic-Bench huggingface dataset:
632 AM EDT Tue Aug 27 2019 A dying warm front will fizzle before it reaches PA this morning. A weak and moisture-poor cold front will approach from the west and move through on Wednesday morning. High pressure will then be centered over the Ohio Valley through the end of the week and keep PA dry. The weak/shearing short wave trough will still end up generating a few hundreths of an inch through the morning and early aftn over the west and central counties. Will hold them where prev shift nudged them down to, but they could easily be another deg or two cooler. The cold front driving the rain/showers could make enough lift over the west to spark a TSRA later tonight, but am more tempted to remove all mentions of thunder from the forecast.
Cooling trend Wednesday through this weekend as some weakening in the ridge occurs. Large scale ridge axis over the region will interact with the remnants of TS IVO and associated inverted trough off the central California coast. Increase in humidity as well as cloud cover will be the greatest impacts as isolated showers and a possible thunderstorm is expected across the high Sierra today and tomorrow during the afternoon. Ridge axis shifts to the east on Wednesday and we will some minor cooling across the region, but still above normal values for this time of year. The upper level high pressure center will remain in SOCAL through the week with continued above normal temperatures across the region and dry conditions expected.
349 AM MDT Tue Aug 27 2019 A broad, diffuse area of high pressure remains over the desert southwest while a deep closed low moves across southern Canada just north of Minnesota. The location of these two features will cause winds to be more north to northwesterly today allowing high temperatures to be a few degrees cooler than seen over the last few days. On Wednesday, the remnants of a tropical system off the Pacific Ocean will rotate around the desert southwest high and start to flatten the high pressure.
The hot pattern continues today with the strong broad ridge keeping the marine layer suppressed.
624 AM CDT Tue Aug 27 2019 Cold front continues to slowly sink to the south across the forecast area early this morning with scattered showers and storms ahead of it. Activity will diminish as cold front exits region by 15z Tuesday.
Latest water vapor imagery shows a broad mid-level trough over the North Plains and Upper Midwest with cyclonic flow across much of the northern and central CONUS. Upper trough will then be evolving and shifting east tomorrow. Of which, southerly flow and warmer temperatures return to the area that will promote highs to be about 5-15 degrees warmer than today. The upper trough will continue to be shifting eastward and will extend from near Hudson Bay to the Tennessee Valley and Middle Atlantic by early Wednesday night. Meanwhile, ridging will be prevailing from the Four Corners to the Pacific Northwest.
A cold front will push across Indiana today and start the day on a rainy note.
Additional widespread showers are anticipated tonight with the passage of a cold front. Showers may linger in the ridges Wed morning, but will wane quickly. Building high pressure at the surface amid broad ern-CONUS troughing will deliver a cooler, drier airmass to the region with minimal chances for rain thru Thu night. Maxima and minima will be below seasonal average as a result of prolonged upper troughing and efficient radiational cooling at night.
Another round of showers is expected this evening and overnight with the arrival of a cold front approaching from the west. Should see rainfall associated with the cold front move east of the area by shortly after midnight tonight.
activity developing along and ahead of a cold front pushing SE into the state.
On Wednesday, an area of low pressure approaching the region from the northwest will bring southerly winds and warmer temperatures in the CWA. Favorable mixing winds, AOA average low level temperatures should produce highs in the low 70s, to the lower 80s.
536 AM MDT Tue Aug 27 2019 A broad, diffuse area of high pressure remains over the desert southwest while a deep closed low moves across southern Canada just north of Minnesota. The location of these two features will cause winds to be more north to northwesterly today allowing high temperatures to be a few degrees cooler than seen over the last few days. On Wednesday, the remnants of a tropical system off the Pacific Ocean will rotate around the desert southwest high and start to flatten the high pressure.
555 AM EDT Tue Aug 27 2019 Update - Decreasing Clouds Today - Dangerous Swim and Boating Conditions into Wednesday - Beach Erosion and lakeshore flooding possible Wednesday - Cooler than normal temperatures through Labor Day The forecast was updated to reflect more coverage of the showers early this morning. Models are generally showing the cold front pushing through early this morning. A secondary surge of cooler air arrives this evening. this cooler airmass stays over the region through most of the weekend.
724 AM EDT Tue Aug 27 2019 Aviation - Decreasing Clouds Today - Dangerous Swim and Boating Conditions into Wednesday - Beach Erosion and lakeshore flooding possible Wednesday - Cooler than normal temperatures through Labor Day The forecast was updated to reflect more coverage of the showers early this morning. Models are generally showing the cold front pushing through early this morning. A secondary surge of cooler air arrives this evening. this cooler airmass stays over the region through most of the weekend.
Less humid and a bit cooler weather can be expected to settle in tonight with lows dropping into the middle and upper 50s with highs on Wednesday in the 70s with abundant sunshine. A cold front was continuing to move southeast and will bring chances for showers and a few storms today.
VFR conditions late this morning for many TAF sites except SSI where a frontal trough continues to result in MVFR ceilings.
High pressure will provide cool/dry weather on Wednesday with highs only in the upper 70s.
Sunny, hot and dry today under a building upper ridge. High temperatures this afternoon will be 5 to 8 degrees warmer than yesterday.
This high will keep conditions dry over the next couple days.
High pressure will build in for the remainder of the short term period, resulting in dry conditions, lower humidity and near normal temperatures.
Well below normal temperatures prevailed today areawide, in the wake of the severe thunderstorms and cold front last night.
241 PM EDT Tue Aug 27 2019 High pressure remains in place aloft this afternoon, while at the surface, Florida resides between low pressure to the northeast and weak high pressure over the eastern Gulf.
A weak cold front will move into the area on Wednesday afternoon. Lower 500 mb heights, slightly cooler 850 temperatures and scattered showers should allow high temperatures to be a few degrees cooler and a Heat Advisory is not expected to be needed. The highest heat index values currently forecast on Wednesday range between 101 and 106 degrees.
Forecast remains consistent from previous runs in the short term with dry high pressure across the region. Temperatures trend upwards into Wednesday with ridge axis beginning to shift west towards East Idaho.
Otherwise, scattered mid/high clouds expected this afternoon as upper trough passes to the north.
This action would form along a pre-frontal trough noted over Middle Tennessee at the current hour.
Temperatures tonight into tomorrow will be cooler for the southern half of the area, and similar to today for the Big Country.
Upper level trough over the Upper Midwest shifts east of the region tonight and Wednesday. Mid level wave diving across east central SD into southwest Minnesota this afternoon and evening will continue to spark isolated showers and weak thunderstorms mainly in the Buffalo Ridge area through sunset. Highs warm a few degrees compared to today, ranging from the lower 70s in southwest MN, to near 80 in south central SD.
Additionally, an increase in moisture will accompany an upper trough axis drifting out of the NW Gulf.
Bulk of morning precipitation has moved south of the forecast area well ahead of a weak surface cold front slowly moving south across the state at midday. activity developing along and ahead of a cold front pushing SE into the state.
1202 PM CDT Tue Aug 27 2019 Cold front continues to slowly sink to the south across the forecast area early this morning with scattered showers and storms ahead of it. Activity will diminish as cold front exits region by 15z Tuesday.
High pressure will remain over the area on Wednesday with northwest flow aloft.
The cold front that we have been anticipating for several days is fairly ill-defined. Wind has already shifted from the North across most of the area, but the lower dew points and cooler temperatures remain in Missouri. Tomorrow, mostly clear skies will still allow temperatures to climb into the middle 80s, but dew points will be around 10 degrees cooler. Coupled with a North breeze, it should feel a bit cooler tomorrow.
200 PM MDT Tue Aug 27 2019 High pressure will strengthen over the Northern Rockies and Montana for dry conditions with near average temperatures today, warming to above seasonal averages on Wednesday.
123 PM MDT Tue Aug 27 2019 The upper trough is shifting eastward into the Great Lakes region, while a ridge builds over the Pacific Northwest.
100 PM PDT Tue Aug 27 2019 Seasonal summer weather is forecast this week as high pressure aloft builds over the Southwest.
1113 AM MDT Tue Aug 27 2019 A broad, diffuse area of high pressure remains over the desert southwest while a deep closed low moves across southern Canada just north of Minnesota. The location of these two features will cause winds to be more north to northwesterly today allowing high temperatures to be a few degrees cooler than seen over the last few days. On Wednesday, the remnants of a tropical system off the Pacific Ocean will rotate around the desert southwest high and start to flatten the high pressure.
930 AM PDT Tue Aug 27 2019 Seasonal summer weather is forecast this week as high pressure aloft builds over the Southwest.
Otherwise, expect high pressure to be the main player this afternoon with cooler than average temperatures near 80 and weak northeasterly winds turning out of the southeast later in the day. Winds will pick up by mid morning out of the southeast 10-15 mph as the pressure gradient tightens due to more of a leeside trough influence off the Colorado Rockies.
336 PM EDT Tue Aug 27 2019 Temperatures are near 90 degrees this afternoon along the Florida Keys, with a stark difference in cloud cover and precipitation between the Upper Keys and the Lower/Middle Keys earlier this afternoon. At the far end of the Lower Keys (Key West), fair weather cumulus clouds along the reverse cloud line struggled to form. Additionally, an interesting aspect of this largely ridge dominated pattern is a small upper- level trough currently located over South Florida. This feature may also be assisting convection that is able to reach that height, as the reflection of this trough does not even extend to the mid- levels of the atmosphere. Tomorrow should be fairly similar to today, with high pressure in the southeastern Gulf gradually translating westward.
The Subtropical Ridge remains centered over the Southwestern states and Northwestern Mexico region with a weaker extension into Texas. While a cold front gradually dissipates to our north, showers and thunderstorms along it will send surface boundaries that will generate showers and thunderstorms for much of our area. However, there is enough subsidence under the weaker Ridge extension to allow for only isolated to perhaps widely scattered areal coverage.
For Wednesday, look for the low level wind flow to be mucked up by outflow boundaries left over from tonight's thunderstorm activity.
Late August heat is building to such a degree that the lower mvfr and ifr layers are finally mixing out into higher broken ceilings across the Great Valley at the current hour.
312 PM EDT Tue Aug 27 2019 Stacked low pressure is spinning over western Ontario this afternoon. A sfc cold front is quickly pushing in from the northwest, and scattered showers have developed just ahead of the boundary. It is a very moist airmass, with sfc dewpoints in the lower 70s and PWATs around 2 inches. The upper trough axis swings through the Ohio Valley on Wednesday.
1115 AM MDT Tue Aug 27 2019 Mid to high level cloud deck currently blanket the Nebraska Panhandle and the far southeast portion of Wyoming as a upper level trough moves east and out of Nebraska. Otherwise, a nice cool, and generally calm day with temperatures in the low to mid 70s across the forecast area, a few degrees below the norm across the board. A ridge of high pressure will begin its push into the region Wednesday, marked by breezy conditions and very dry conditions along and west of the Laramie Range.
A cold front will be moving into the area on Wednesday and as it does, the best moisture will be moving off to the east.
1142 AM EDT Tue Aug 27 2019 A weak warm front and moist, low-level southeasterly flow ahead of it will bring widespread clouds and occasional showers or drizzle for the rest of today. A weak and moisture- poor cold front will approach from the west and move through on Wednesday morning. High pressure will then be centered over the Ohio Valley through the end of the week and keep PA dry. The cold front driving the rain/showers could make enough lift over the west to spark a TSRA later tonight, but am more tempted to remove all mentions of thunder from the forecast.
151 PM CDT Tue Aug 27 2019 An upper level low is forecast to remain over western Ontario this afternoon, with upper level impulses rotating around the low. Winds and clouds will decrease during the evening hours as the low pressure system lifts northeastward towards Hudson Bay. As an upper ridge axis nudges closer to the western Dakotas from the western US, clear skies and light winds will allow temperatures to dip into the upper 30s across the far southwest, where some patchy frost may be possible overnight. Look for high temperatures to range from the lower 80s over southwestern North Dakota to the lower 70s in the Turtle Mountains and James Valley.
328 PM CDT Tue Aug 27 2019 At 19Z, a midlevel low was spinning over Ontario with a trough axis rotating around the cyclonic flow across the Upper Midwest. Midlevel ridging was in place over the western CONUS. However, locations in central and north-central Kansas may notice a slight increase in temperatures due to a return of southerly winds on the west side of the departing ridge.
These showers are a result of a weak ribbon of mid level frontogenesis and instability, as main upper trof drops into the northern plains (ie to our east). Cloud cover has kept temps a bit warmer than previously expected, with most areas still in the low-mid 50s, and 40s up in Wheatland County. Flat upper level ridging will bring us dry conditions today and Wednesday.
223 PM CDT Tue Aug 27 2019 Temperatures this afternoon are running a good 20 to 30 degrees cooler than yesterday at this as we sit in a post-frontal air mass with widespread stratus helping to keep temperatures down as well.
This coupled with an upper level short wave trough moving this way in a northwest flow aloft should help to increase the shower and thunderstorm chances.
146 PM EDT Tue Aug 27 2019 Aviation - Decreasing Clouds Today - Dangerous Swim and Boating Conditions into Wednesday - Beach Erosion and lakeshore flooding possible Wednesday - Cooler than normal temperatures through Labor Day The forecast was updated to reflect more coverage of the showers early this morning. Models are generally showing the cold front pushing through early this morning. A secondary surge of cooler air arrives this evening. this cooler airmass stays over the region through most of the weekend.
239 PM CDT Tue Aug 27 2019 Showers started popping up this afternoon along what looks to be a pressure trough/convergence zone ahead of the main front further west.
Wednesday remains dry, however high temperatures will be about 10 deg above average under a broad ridge.
214 PM CDT Tue Aug 27 2019 214 PM CDT Post cold front, the region remains under the influence of closed upper closed low over southwest Ontario. Several smaller scale perturbations that will rotate around it as this low meanders slowly toward Hudson Bay. One such stronger wave on the southern end of the low will continue to drive some showers and storms across WI this afternoon. This will steepen the low-level lapse rates further. Temperatures look to peak in the lower to mid 70s with a cool pocket of 850 mb temperatures of 7-8C passing across areas along and north of I-88.
Thunderstorm chances will continue mainly along the high terrain through the holiday weekend. High pressure centered over the southwestern U.
High pressure filtered into the central plains of the United States this afternoon. Northeast of the area low pressure was moving through Canada. This high pressure will drive the weather through the short term period. Unlike today, the high pressure will be more directly over the area as such, mixing will not result in much of a wind gust. Dewpoints would suggest that we should see low temps in the low 50s. With the wind, have decided to go slightly warmer than this. While this flow will see some active periods overall expect a pattern of cooler drier air and then a quick shot of deep moisture followed by chances for rain and storms. At the end of the period, the pattern is expected to change with a ridge building in and hot temperatures returning to the area.
Showers started popping up this afternoon along what looks to be a pressure trough/convergence zone ahead of the main front further west.
Shallow upper level ridging should keep dry conditions in place through Wednesday night. A cold front will drop into the region late Wednesday night.
Westerlies begin to lift nwd with high pressure building back into area.
413 PM CDT Tue Aug 27 2019 Latest surface analysis showed a cold front from the Great Lakes region to northern Arkansas to west Texas. A 1021mb high was located over northern Plains and weak pressure gradient was present over the Lower Mississippi Valley and forecast area. Upper air analysis revealed a deep low just north of Minnesota with broad trough over the northern and central Plains. A weak trough axis was located over Oklahoma and north central Texas. 18 Trough axis over Oklahoma and north central Texas will push southeast and south through Wednesday.
527 PM MDT Tue Aug 27 2019 The upper trough is shifting eastward into the Great Lakes region, while a ridge builds over the Pacific Northwest.
As the weak already diffuse cold front near Waco sags southward may see some redevelopment along the boundary in the northern counties around midnight through 4 am.
This upswing in activity appeared to be in response to the upper high becoming centered west of the area by Wednesday night. The relocation of the upper high will result in a north to northeast steering flow thereby helping track storms off the mountain ranges into the lower deserts.
741 PM EDT Tue Aug 27 2019 A cold front will continue to work through the region this evening. High pressure will then move in allowing for dry conditions.
South Florida will be located between weak ridging over the Gulf of Mexico and an upper low over the eastern Bahamas. High pressure over the northern Atlantic waters will allow the steering flow to become more easterly over South Florida. Our focus during this time remains on Tropical Cyclone Dorian as it moves through the region. Tropical Cyclone Dorian may then impact boating conditions for late week into the weekend, with hazardous conditions possible.
Aloft an upper low has retro graded by to near Houston and is providing a modest amount of divergence across SETX and South Louisiana, hence the storms.
Chattanooga Airport, TN 71 87 62 86 / 40 10 10 0 Knoxville McGhee Tyson Airport, TN 70 85 59 85 / 60 10 10 0 Oak Ridge, TN 69 85 60 84 / 60 10 10 0 Tri Cities Airport, TN 66 83 58 80 / 50 30 10 0.
/issued 223 PM CDT Tue Aug 27 2019/ Temperatures this afternoon are running a good 20 to 30 degrees cooler than yesterday at this as we sit in a post-frontal air mass with widespread stratus helping to keep temperatures down as well.
Most of the lower clouds should dissipate late tonight, but may reform in the morning, especially in southern Oklahoma and north Texas.
High pressure ridging has brought another hot day to the area.
Changes for the eve update were primarily cosmetic as showers and a few thunderstorms continue to progress eastward across Ohio with a cold front. Showers may linger in the ridges Wed morning, but will wane quickly. Building high pressure at the surface amid broad ern-CONUS troughing will deliver a cooler, drier airmass to the region with minimal chances for rain thru Thu night. Maxima and minima will be below seasonal average as a result of prolonged upper troughing and efficient radiational cooling at night. A prolonged period with an ern-CONUS trough and wrn-CONUS ridge will maintain temperature near or slightly below seasonal average through the weekend. Conditions should further deteriorate in showers and isolated thunderstorms with the passage of the cold front tonight.
Otherwise, mild temperatures are expected with lows in the low to mid 70s.
With surface dew points continuing to lower tonight along with weakening surface winds, the minimum temperatures will be cooler and 5 to 10 degrees below normal for late August.
An upper-level trough currently located over Minnesota rotates east across the Great Lakes region through the next 24 hours, bringing a broad troughing pattern to the eastern CONUS during that time. A surface cold front associated with this system pushes southeast towards the local area tonight into Wednesday.
652 PM CDT Tue Aug 27 2019 214 PM CDT Post cold front, the region remains under the influence of closed upper closed low over southwest Ontario. Several smaller scale perturbations that will rotate around it as this low meanders slowly toward Hudson Bay. One such stronger wave on the southern end of the low will continue to drive some showers and storms across WI this afternoon. This will steepen the low-level lapse rates further. Temperatures look to peak in the lower to mid 70s with a cool pocket of 850 mb temperatures of 7-8C passing across areas along and north of I-88.
Changes for the eve update were primarily cosmetic as showers and a few thunderstorms continue to progress eastward across Ohio with a cold front. Showers may linger in the ridges Wed morning, but will wane quickly. Building high pressure at the surface amid broad ern-CONUS troughing will deliver a cooler, drier airmass to the region with minimal chances for rain thru Thu night. Maxima and minima will be below seasonal average as a result of prolonged upper troughing and efficient radiational cooling at night. A prolonged period with an ern-CONUS trough and wrn-CONUS ridge will maintain temperature near or slightly below seasonal average through the weekend. Conditions will deteriorate just ahead of and after the passage of the cold front tonight, with showers and an isold tstm along the boundary.
Also re-ran temperatures based on current trends as temps in the north remain much cooler than expected today behind a remnant outflow boundary. The Subtropical Ridge remains centered over the Southwestern states and Northwestern Mexico region with a weaker extension into Texas. While a cold front gradually dissipates to our north, showers and thunderstorms along it will send surface boundaries that will generate showers and thunderstorms for much of our area. However, there is enough subsidence under the weaker Ridge extension to allow for only isolated to perhaps widely scattered areal coverage.
1032 PM EDT Tue Aug 27 2019 A cold front will continue to work through the region this evening. High pressure will then move in allowing for dry conditions.