Aikyam-Lab/Synoptic-Bench huggingface dataset:
Late in the period, thunderstorm chances will increase slightly across far NE OK ahead of an approaching cold front. /Issued 1033 AM CDT Thu Sep 2 2021/ Upper ridge beginning to flatten some in response to an upper wave that will move through the high plains today. This feature will aid in pushing a cold front towards the area tonight and tomorrow. Current forecast in good shape with a 'slightly' cooler afternoon expected. /Issued 340 AM CDT Thu Sep 2 2021/ Isolated convection has been maintained over far SE OK early this morning within a corridor of deeper moisture and slightly cooler mid level temps. Near persistent conditions expected Friday while convection edges closer to NE OK late Friday as ridging aloft flattens.
An upper ridge whose axis is currently over the upper Mid-West will flatten as it slides eastward across the Mid-West. Lower levels will meanwhile enjoy another day of Canadian high pressure as its center slides from the Great Lakes this evening to Ohio and eastward by late Friday. Light east-southeasterly breezes will bring another rather mild day across the CWA, albeit perhaps 1-2 degrees warmer for southern and western counties courtesy of the light return flow.
The short wave trough that brought storms to the area last night and early this morning is moving over the plains states today. Clouds and showers this morning kept temperatures a little cooler over the far eastern sections of the forecast area, which has delayed the development of thunderstorms so far this afternoon. A cooler airmass sags south across the area by Friday with a the frontal boundary at its periphery remaining over the western and southern portions of the forecast area.
This drying trend will also bring warmer temperatures to the region with readings gradually increasing to near and slightly above normal levels. Over the next 72 hours, subtropical ridging centered over the southern plains will split in response to northern stream jet energy amplifying the Conus flow pattern and digging negative height anomalies over the northern plains and Great Lakes. The western lobe of high pressure should retrograde and intensify into a 594dm ridge centered on southern CA/NV. Ensemble spread is still rather wide, especially closer to the anti-cyclone center through the western CWA where a 30-50% chance of readings reaching 110F still exists. Thunderstorm chances through the weekend will be primarily limited to the higher terrain locations of the eastern forecast area.
Behind this departing wave, zonal surface ridging is forecast to build in from the west as flow aloft becomes more cyclonic in response to a closed mid level cyclone over northern Manitoba. The deepening cyclonic flow regime to the north will allow a cooler air mass to filter into the region. This weekend will start out with northwest cyclonic flow aloft and broad subsidence in the lower levels.
1245 PM CDT Thu Sep 2 2021 (Today and tonight) Hot and dry today with upper ridging suppressing shower and thunderstorm development. Lee trough along the Texas and New Mexico state line will bring southeast to south winds of 5 to 15 mph.
1033 AM CDT Thu Sep 2 2021 Upper ridge beginning to flatten some in response to an upper wave that will move through the high plains today. This feature will aid in pushing a cold front towards the area tonight and tomorrow. Current forecast in good shape with a 'slightly' cooler afternoon expected. /Issued 340 AM CDT Thu Sep 2 2021/ Isolated convection has been maintained over far SE OK early this morning within a corridor of deeper moisture and slightly cooler mid level temps. Near persistent conditions expected Friday while convection edges closer to NE OK late Friday as ridging aloft flattens.
A ridge of high pressure will keep skies mostly clear across the area through Friday. We should see highs in the mid to upper 70s today and in the upper 70s on Friday for all but a few counties along the Tennessee border, where the mercury could reach the lower 80s. Tonights lows will be the coolest we've had since the spring, with minimum readings in the lower 50s expected for most locations. Upper level ridging will begin to retreat westward, as a longwave trough and low work east through Southern Canada.
231 PM CDT Thu Sep 2 2021 Cooler and drier air filters into the region behind the front, resulting in more comfortable conditions across the region. Temperatures will only climb into the 80s in most locations on Friday with the Delta most likely in the lower 90s. With dewpoints only in the 60s, however, it should feel considerably cooler, with heat index values in the mid 80s to lower 90s. Tomorrow night through Thursday: The forecast period starts off tomorrow night with sub-tropical ridging centered over the Lower Mississippi Valley.
Aside from smoke, we had another chilly start to the day, especially across the high mountain valleys and mountains where sub freezing temperatures returned.
Min temperatures tonight look to be similar to this morning, even as high clouds begin to arrive by sunrise (as temps probably fall a bit quicker this evening due to the lower dew pts compared to 24 hrs ago).
240 PM CDT Thu Sep 2 2021 Mid level moisture remains in place across the forecast area this afternoon from southwest to northeast as upper level ridging continues to dominate our weather pattern. Latest mesonet observations as of 2 pm indicate weak surface convergence occurring from near Denver City to Floydada, with a theta-e ridge from near Friona back to Snyder. Similar to last night the low level jet is expected to ramp up this evening which may keep shower and thunderstorm activity going across the Caprock into the early morning hours of Friday. Afternoon temperatures on Friday will be in the low 90's on the Caprock, and in the mid to upper 90's off of it.
1234 PM CDT Thu Sep 2 2021 Updated for 18Z aviation discussion 18Z TAF discussion: High pressure building into the region behind a frontal boundary will bring drier air and light winds. Though a cold front is making it's way through the region, the boundary is little more than a wind shift with cooler/drier air lagging far behind. Prior discussion below: A cold front moves south across the area today with noticeably drier conditions and rain chances in general lowering from north to south through the day into the overnight. Temperatures will be a bit cooler today but still quite warm, in the lower 90s F and upper 80s F. The remnant circulation of Ida has helped to reinforce a trough axis to our east and the northerly flow behind this departing weather maker will result in seasonably deep frontal penetration.
Expect greatest storm coverage over, and to the east of the highest terrain - diminishing this evening. Scattered thunderstorms are expected to initiate around 1000-1200 LST over mountain peaks and ridges and then move off those terrain features into the later afternoon hours.
Convection will be less widespread tomorrow, as ridging builds overhead. /issued 424 AM CDT Thu Sep 2 2021/ A cold front extends from the upper plain states across into the New England states and down towards the Gulf Coast and is the focus of most of the storm activity this morning. In the middle and upper portion of the atmosphere the ridge that has been hanging over Texas is expected to spread into Louisiana and this will lower the chances for storms during the afternoon hours. a small area of low pressure near the coast of Nicaragua is producing some disorganized shower and thunderstorm activity.
311 PM EDT Thu Sep 2 2021 High pressure builds in from the north through the weekend.
202 PM EDT Thu Sep 2 2021 High pressure will provide a rain-free forecast through the rest of this week, with noticeably cooler and drier air.
Scattered clouds are being observed along the divide and ahead of an approaching trough over the southeastern third of the forecast area. Temperatures tonight should generally run a few degrees warmer than last night thanks to some additional cloud cover, but the higher valleys could still see 20s and lower 30s for lows.
Temperatures in the Sacramento Valley are generally running within several degrees of what they were this time yesterday, while temps in the San Joaquin Valley are running about 5 to 7 deg cooler. Over the next several days, upper level ridge over the Desert Southwest will strengthen and expand west towards the Golden State.
High pressure over the Mississippi Valley will keep dry weather for Alabama through Friday. Mid and low level flow will change to out of the south and southwest bringing moisture an warmer air for Friday afternoon.
235 PM CDT Thu Sep 2 2021 A low pressure system currently over central South Dakota slides into central Iowa by Friday morning. This band of precipitation slowly spreads eastward across the forecast area between 00-12Z tonight and persists for much of the day on Friday as the low weakens and dives southeastward.
There is a better chance of showers Friday across central Wisconsin as weak low pressure approaches from Minnesota.
Visible satellite shows a few cloud streamers coming off of the Lower Keys and Marquesas and some mid-upper level clouds moving southeast off the convection to the north of our area. Water vapor imagery showers two prominent features near our area this afternoon; an upper-level low spinning northeast of the Bahamas and a trough along southeast coast and extending across Gulf coast. CIMSS MIMIC TPW highlights a band of higher moisture moving closer to south Florida ahead of the trough, however, it will likely not make it to the Keys tonight. The aforementioned trough and associated surface boundary will migrate south over the next few days.
1158 AM CDT Thu Sep 2 2021 Area of moderate llvl speed convergence developed near the coast earlier this morning (& where the highest moisture availability was located) which allowed for a broken band of shra/tstms to develop.
5" precipitable water values) as well as strong winds (decently high temperature-dewpoint spreads in the lower levels according to forecast soundings). Most areas in central Oklahoma will remain dry due to the predominance of the upper level ridge in the region.
143 PM EDT Thu Sep 2 2021 High pressure builds in from the north through the weekend.
/Tonight through Friday Night/ Upper-level ridge gradually building across the region will maintain hot temperatures through the short term period with highs on Friday in the mid to upper 90s and overnight lows in the low to mid 70s. Should see lesser coverage on Friday as upper-ridge become more firmly established areawide.
While surface dew points in the 50s to around 60 will hold thru the day tmrw, they begin to nudge upwards again as a cold front takes shape and begins its approach from the northwest Friday night.
Friday will be another hot day underneath the upper level ridge as highs again soar into the upper 90s for most of the area. The ridge will begin to get squashed a little tomorrow in response to an upper wave moving across the Northern Plains throughout the day.
229 PM EDT Thu Sep 2 2021 High pressure located over the northern Great Lakes continues to provide the Ohio Valley with outstanding weather this afternoon. Tonight into tomorrow, the upper level ridge over the lower MS Valley will begin to flatten as a weak mid-level wave moves along the peripheral of the ridge from IA across IL into the Ohio Valley tomorrow. While lows tomorrow morning will once again drop into the 50s (with low 60s across our urban metro areas) the high clouds should keep them in the mid/upper 50s. A few isolated locations, especially across the Bluegrass and eastern CWA, could drop into the low 50s. Highs during the afternoon will once again range from the low 80s to upper 70s.
As the aforementioned PV anomaly approaches tonight, return flow ahead of a deepening sfc cyclone will likely promote destabilization, with at least 500-1000 J/kg of MUCAPE progged over nern WY by 09-12z tomorrow AM per the 12z HREF mean, with latest HRRR/NAM runs suggesting higher values. Sfc cyclone further deepens thru early aftn tomorrow, with pressure falls of 2-4 mb/3 hr supporting continued return flow and moisture advection into srn portions of nern WY and swrn SD.
These features will remain in control right on into the weekend, but highs will be a bit warmer on Fri. By Sat morning, a cold front drops down into the OH valley and by Sun morning, it sets up just northwest of the area ahead of an upper wave. This upper low/wave looks stronger and will again push this front south, and out of the picture on Wed.
The upper level troughing over the eastern CONUS continues to shift offshore through the period as upper level ridging over the south central CONUS builds east into the forecast area. The building ridge will cause a more north to northeasterly mid to upper level flow. At the surface, a cold front sags south across the area this afternoon and then lingers over the offshore waters through the remainder of period. The increased subsidence from the building ridge in combination with dry air advection aloft will help dry out the atmospheric column and support significantly lower rain chances through the period.
/NEW/ /Through Friday/ The heat continues across North/Central TX today as the strong mid-level ridge remains in place across the region.
Near seasonal/tranquil conditions prevail across the cntrl TN Valley this late Thu morning, as a large dome of high pressure gradually builds E/SE over the Great Lakes/OH Valley states. Consensus guidance from the latest suite of global models continues to suggest that the Southern Plains mid-level ridge will become centered across eastern OK/western AR during the short term period, but should gradually expand eastward to encompass much of the Gulf Coast states.
Dry and cool conditions expected today as a trough moves through the forecast area. This trough will keep temperatures below normal through Friday. The trough will also produce gusty wind as it progresses eastward.
Expect refreshingly cooler and more comfortable conditions with no precipitation forecast through the first part of the weekend. High pressure migrating over CPA and off the Mid-Atlantic coast maintains fair weather into the weekend.
1050 AM CDT Thu Sep 2 2021 Near seasonal/tranquil conditions prevail across the cntrl TN Valley this late Thu morning, as a large dome of high pressure gradually builds E/SE over the Great Lakes/OH Valley states. Consensus guidance from the latest suite of global models continues to suggest that the Southern Plains mid-level ridge will become centered across eastern OK/western AR during the short term period, but should gradually expand eastward to encompass much of the Gulf Coast states.
1155 AM CDT Thu Sep 2 2021 Latest radar imagery showers showers and thunderstorms west of our area beginning to encroach upon the region, with current temperatures hovering in the low to mid 60s. Should see precipitation gradually begin to diminish from west to east heading into the evening and overnight period, as the sfc cold front departs the region. Otherwise, look for dry conditions and seasonably cooler temperatures to prevail during the holiday weekend. Heading into the new week, expect upper level ridging to build over the western CONUS.
218 PM EDT Thu Sep 2 2021 Fall-like temperatures persist today and tomorrow as Canadian high pressure takes control of the region.
Otherwise, high pressure will continue to result in dry conditions under mostly sunny skies. High temperatures this afternoon still expected to top out mostly in the lower to middle 70s. High pressure continues to be over the Upper Great Lakes again today with the 500 mb ridge axis in the Mississippi Valley. This should help us maintain a little warmer on the low temperature for tonight/Friday morning. As the 500 mb ridge moves into the region Tonight, the high clouds will make more in roads as well.
High pressure over the Mississippi Valley will keep dry weather for Alabama through Friday. Mid and low level flow will change to out of the south and southwest bringing moisture and warmer air for Friday afternoon.
254 PM MDT Thu Sep 2 2021 Upper trough over the Pacific Northwest will move eastward tonight into Friday and bring scattered showers to south central MT and numerous showers over southeast MT and north central WY.
The highest rain chances will again be over the middle Texas coast and Victoria Crossroads.
trough with remnants of Ida continues to focus deep moisture in convergent westerly flow across the region. The good news is that this feature will gradually lift northeast, allowing some upper-level ridging to build in from the west this weekend.
256 PM CDT Thu Sep 2 2021 Latest water vapor imagery is showing the upper ridge axis centered over Missouri and Illinois bringing dry weather to the area. Latest surface analysis showed high pressure centered north of the Great Lakes with a front extending from the Plains across the Gulf Coast.
Clear, dry, and seasonably cool weather tonight and Friday across the region with high pressure in control. High pressure will continue to result in light NE winds across the area with a clear sky. Temperatures are forecast to be a degree or two warmer, but temperatures remain near or slightly below seasonal normals across the region with a mostly clear sky and light winds.
Likely it will end up cooler then last night. Expect lows well into the 40s north and east of Grand Rapids and normally cooler locations.
933 PM EDT Thu Sep 2 2021 High pressure will build into the region through the first part of the weekend.
600 PM CDT Thu Sep 2 2021 A low pressure system currently over central South Dakota slides into central Iowa by Friday morning. This band of precipitation slowly spreads eastward across the forecast area between 00-12Z tonight and persists for much of the day on Friday as the low weakens and dives southeastward.
As the low level boundaries move offshore, expect the inland conv to diminish with the loss of the daytime heating and the surface convergence.
No changes are need to the forecast this evening as high pressure from the surface through the upper levels will remain firmly in control overnight. Clear skies are expected as cirrus rounding the ridge should stay to our west. VFR conditions are forecast to prevail at all sites this period as high pressure dominates the Southern Appalachian region. Clear, dry, and seasonably cool weather tonight and Friday across the region with high pressure in control. High pressure will continue to result in light NE winds across the area with a clear sky. Temperatures are forecast to be a degree or two warmer, but temperatures remain near or slightly below seasonal normals across the region with a mostly clear sky and light winds.
928 PM CDT Thu Sep 2 2021 A broad high pressure system centered over the Great Lakes is leading to dry northeasterly winds across the Tennessee Valley this evening. Mostly clear skies prevail while upper level ridging begins to build into the Southeast.
625 PM CDT Thu Sep 2 2021 H5 analysis this morning had high pressure anchored over Texas. A ridge of high pressure extended north of the Arklatex into southern portions of Hudson Bay Canada. East of this feature, a trough of low pressure extended from eastern Quebec, south into the Delmarva Peninsula. West of the ridge, closed low pressure was located over central Saskatchewan with a trough extending southwest into northern portions of California. At the surface this afternoon, a cold frontal boundary was located from Bassett to Brewster to just east of North Platte. Overnight, weak high pressure will try to build into northern Nebraska.
A trough moving into the northern Great Basin this evening will provide dynamics to produce some thunderstorms, possible strong over northwest Utah.
655 PM EDT Thu Sep 2 2021 Expansive area of high pressure anchored over the region maintains a dry and stable low level environment this taf period. This ensures VFR conditions with clear skies across the lowest 10k ft. Min temperatures tonight look to be similar to this morning, even as high clouds begin to arrive by sunrise (as temps probably fall a bit quicker this evening due to the lower dew pts compared to 24 hrs ago).
Temperatures tonight will be moderated by the dense cloud cover, leaving most of the area in the low 60s.
645 PM CDT Thu Sep 2 2021 Latest water vapor imagery is showing the upper ridge axis centered over Missouri and Illinois bringing dry weather to the area. Latest surface analysis showed high pressure centered north of the Great Lakes with a front extending from the Plains across the Gulf Coast.
/EC/ Prior discussion below: Cooler and drier air filters into the region behind the front, resulting in more comfortable conditions across the region. Temperatures will only climb into the 80s in most locations on Friday with the Delta most likely in the lower 90s. With dewpoints only in the 60s, however, it should feel considerably cooler, with heat index values in the mid 80s to lower 90s. Tomorrow night through Thursday: The forecast period starts off tomorrow night with sub-tropical ridging centered over the Lower Mississippi Valley.
Otherwise, 500 mb ridging in place over much of TX will likely maintain pretty stable conditions throughout the overnight hours. A mid-level ridge centered over northern Texas and Oklahoma will continue to give us an easterly flow throughout the column. The best chance for rain will be along the sea breeze and Northern Ranchlands, where they will be a bit closer to the highest PWATs.
Some periods of IFR possible in TSRA and then again later tonight behind the cold front that will move through the region.
/issued 240 PM CDT Thu Sep 2 2021/ Mid level moisture remains in place across the forecast area this afternoon from southwest to northeast as upper level ridging continues to dominate our weather pattern. Latest mesonet observations as of 2 pm indicate weak surface convergence occurring from near Denver City to Floydada, with a theta-e ridge from near Friona back to Snyder. Similar to last night the low level jet is expected to ramp up this evening which may keep shower and thunderstorm activity going across the Caprock into the early morning hours of Friday. Afternoon temperatures on Friday will be in the low 90's on the Caprock, and in the mid to upper 90's off of it.
The upper level troughing over the eastern CONUS continues to shift offshore through the period as upper level ridging over the south central CONUS builds east into the forecast area. The building ridge will cause a more north to northeasterly mid to upper level flow. At the surface, a cold front sags south across the area this afternoon and then lingers over the offshore waters through the remainder of period. The increased subsidence from the building ridge in combination with dry air advection aloft will help dry out the atmospheric column and support significantly lower rain chances through the period. Lows tonight will be slightly cooler than what we've seen lately, dipping down into the mid 60s inland with lower 70s along the coast.
Scattered thunderstorms today will become more limited in coverage this weekend, with only isolated storms expected over the higher terrain.
High pressure located over the northern Great Lakes continues to provide the Ohio Valley with outstanding weather this afternoon. Tonight into tomorrow, the upper level ridge over the lower MS Valley will begin to flatten as a weak mid-level wave moves along the peripheral of the ridge from IA across IL into the Ohio Valley tomorrow. While lows tomorrow morning will once again drop into the 50s (with low 60s across our urban metro areas) the high clouds should keep them in the mid/upper 50s. A few isolated locations, especially across the Bluegrass and eastern CWA, could drop into the low 50s. Highs during the afternoon will once again range from the low 80s to upper 70s.
Much cooler temps are expected in the morning as a slight taste of fall is in store for the Mid South.