Aikyam-Lab/Synoptic-Bench huggingface dataset:
Short range models continue to indicate a series of weak H5 vort maxima associated with a modestly increasing northwest flow aloft dropping out of the Northern High Plains into the high plains of western Nebraska and northwest Kansas later this afternoon/evening. Weak northeast flow aloft becomes established late in the weekend with still plenty of deep, rich moisture in the region to support any convection coming off the high plains to feed into sufficient late day or evening instability.
A diurnal trend in convective coverage is forecast again on Saturday afternoon with greatest coverage along the higher terrain. Showers will develop earlier than normal (late morning) with a cold front moving into the region. McD Chattanooga Airport, TN 92 72 90 71 84 / 60 40 80 40 70 Knoxville McGhee Tyson Airport, TN 92 70 88 70 85 / 60 40 80 40 70 Oak Ridge, TN 90 70 87 69 83 / 60 40 80 40 70 Tri Cities Airport, TN 88 67 85 67 82 / 60 30 80 40 80.
Temperatures this afternoon are in in the lower 80's across the whole area, with dewpoint temperatures falling to as low as 48 at KOFK. Areas near the NE/SD border are expected to be slightly warmer and could reach as high as 90 degrees.
A weak warm front and low level jet are the primary forcing tonight. Barring significant storm coverage tonight, the slight warming aloft Sunday supports highs a few degrees warmer than today.
The area will be within a weak trough for Sunday which will continue to keep temperatures below normal and will keep a chance for showers and storms in the forecast for parts of the area.
/EC/ Prior discussion below: Through Saturday: Broad mid/upper troughing over the eastern US will build slightly southward as we head into the weekend, with an associated cold front seeping slowly through the Mid MS Valley and into the Mid South. and the weakening of the subtropical ridge.
230 AM MDT Sat Aug 14 2021 An upper level ridge centered roughly across Nevada and Utah will result in light west to northwest flow aloft. On Sunday, the upper ridge is progged to retrograde westward with light to modest northwest flow aloft. High temperatures are expected to be slightly cooler Sunday in most locations due to an increase in convection and the upper- high sliding westward, but still expecting above average temperatures both days. The dome of high pressure sitting to the west of the area will usher northwest flow over the CWA which will keep the area mostly dry with seasonal temperatures.
344 AM EDT Sat Aug 14 2021 Showers and thunderstorms will again be limited in coverage today as the upper level ridge begins retreating into the Atlantic this afternoon. Synoptic situation will begin slowly changing this afternoon as the upper level ridge which has been over the area begins retreating into the Atlantic Basin. High temperatures this afternoon will be in the mid 90s with lows tonight again in the low to mid 70s.
Northeast winds will continue to usher in a drier airmass with dewpoints in the lower 60s possible by afternoon. Cooler valleys and in the eastern ozarks may dip into the middle 50s. High pressure over the Great Lakes will continue to usher drier air in for Sunday.
Late week looks to feature the approach of upper level troughing which may result in increasing precipitation chances.
Near the surface, an area of low pressure remains anchored in southeast Colorado. Still this afternoon, the reflectivity returns across the south indicate sprinkles while the visible satellite red band imagery supports the thicker mid level stratus associated with the upper deformation zone - which all still supports the cooler solution trend. Weak northeast flow aloft becomes established late in the weekend with still plenty of deep, rich moisture in the region to support any convection coming off the high plains to feed into sufficient late day or evening instability.
(Today and tonight) Early this morning, much of central Texas remained underneath an upper ridge that was breaking down due to a larger scale trough digging into the southern Plains.
Tonight Through Sunday High pressure aloft continues across the southern and western U. The upper trough remains over the Great Lakes. The trough will expand southward into the mid Mississippi Valley by Sunday. The cold front near the Missouri border will stall along the border tonight through Sunday.
1034 PM MDT Fri Aug 13 2021 Broad upper ridging covers the western CONUS, with northwest flow over the northern plains. At the surface, high pressure sits over the Dakotas, and winds are light and variable. The warming trend will continue through the weekend, as the upper ridge persists and the low-level thermal ridge gradually strengthens and spreads eastward. Highs Saturday will be in the lower 90s on the plains, 70s/80s in the Black Hills.
The clear skies, light winds, and lower dew points will also allow for cooler temps once again. Overnight lows will range from the low to middle 40s across the Northwoods, to the upper 40s to middle 50s from east- central WI to the lake shore. Very few clouds are expect as high pressure slides across the state.
1255 AM EDT Sat Aug 14 2021 A cold front will finally cross the region this morning, pushing the threat of showers and storms southward and ushering in cooler and more comfortable air. The crossing trough will also pull a surface cold front southeastward, passing just southeast of PIT around dawn. Broad high pressure will settle in on Sunday.
These storms are out ahead of a cold front that is draped across Indiana, Illinois and through the Plains. The upper level ridge that has weakened over the past 24 hours will hang out over our area which will allow for daily showers and thunderstorms through late week. The low clouds/fog combined with the amount of convection earlier across the region seems to point to much less SHRA/TSRA activity on Saturday areawide.
SHORT TERM (Now through Sunday): Weak 500 mb high pressure will persist over the BRO CWFA during the period.
355 AM EDT Sat Aug 14 2021 A cold front will finally cross the region this morning, pushing the threat of showers and storms southward and ushering in cooler and more comfortable air. Broad high pressure will settle in on Sunday.
420 AM EDT Sat Aug 14 2021 Showers and a few rumbles of thunder will continue through the morning hours as a cold front slowly tracks eastward. The well anticipated cold front is slowly trekking eastward and is now across northern New York. Temperatures will trend cooler behind the cold front, finally bringing relief to the heat and humidity that we've experienced this week. High pressure will then begin to encroach upon the region during the overnight hours and through Sunday.
This added rainfall may lead to the development of IFR to MVFR ceilings closer to daybreak however it remains unclear how moist the lower levels will remain after the rainfall comes to an end. Through the next 24 hours the monsoonal plume is progged to shift southward as upper level high pressure over the Rockies is able to build to the southeast behind a short wave trough exiting the central Plains to the Ohio Valley.
1049 PM MDT Fri Aug 13 2021 Thanks to benign northwest flow aloft and a slowly building ridge, quiet weather is expected through noon Saturday with mostly clear skies, light winds, and temperatures about 5 degrees above average. A subtle vorticity maximum moves through the low-amplitude ridge, and the associated vertical motion should provide a focusing mechanism for afternoon convection. Another subtle upper-level feature moves through the weakening ridge on Sunday, and this could bring additional showers and thunderstorms to the central portion of the state, primarily over the mountains.
High temperatures will be warmer based on 700 mb temperature forecast.
Prevailing southerly sfc flow is facilitating impressive low-level moisture advection across the High Plains overnight, with 60+ degree dew points now extending most of the way thru the NE panhandle. This is also where the highest potential (albeit still a low chance) for locally enhanced shear and thus supercell modes/severe weather exists.
High pressure is dominating the area resulting in clear skies and calm winds.
An upper level trough is still projected to push inland across the Pacific Northwest Sunday night, leading to a flattening of the high over the Great Basin.
A slow-moving frontal boundary (and troughing ahead of it) will continue to instigate rounds of convection today and through the rest of the weekend. The trough axis ahead of the frontal boundary will also shift slowly southward across the Ark-La-Tex, pulling some light northwest winds into our northern zones. The cloud cover associated with this round of showers and thunderstorms will continue to keep temperatures in the low 90s and upper 80s, and the aforementioned frontal boundary is expected to cross the Ozark Mountains by Sunday evening.
and Sunday High pressure will keep the area dry with mostly sunny skies this weekend, as temperatures slowly warm as the high shifts east and surface winds shift to a west southwesterly direction today and a southwesterly direction on Sunday.
Weak ridging will shift to the west slightly today which should allow for a slightly higher coverage of isolated showers today for our area. High temperatures today should be about a degree or two cooler in some spots with the increased moisture. Rainfall coverage on Sunday will be the highest of the forecast period with the boundary now expected to be draped across the CWA as it continues its southward trek serving as the focus for initiation. Highs on Sunday will likely be the coolest of the forecast period with temps peaking in the lower to middle 90s for most of the area.
The high will also sustain light winds through the TAF period. The cold front is slowly dropping across SE MI this afternoon, currently residing in between I-69 and M-59. Much drier air follows the front with upstream dewpoints over northern lower already down in the low 50s/upper 40s helping to clear skies out for tonight.
Short range models continue to indicate a series of weak H5 vort maxima associated with a modestly increasing northwest flow aloft dropping out of the Northern High Plains into the high plains of western Nebraska and northwest Kansas later this afternoon/evening. An outside chance for thunderstorms exists late Sunday as medium range models indicate a relatively weak upper level disturbance transitioning through the northwest flow aloft across the high plains of eastern Colorado/western Kansas. Near the surface, pooling moisture within a southeasterly upslope flow will provide ample instability ahead of a slowly deepening lee side trough of low pressure in eastern Colorado.
High fire danger and hot temperatures are concerns for late Upper ridging across the western U.
High pressure will gradually slide eastward from northwest Iowa into the Great Lakes Sunday. Southerly return flow will develop today and push temps a little warmer with highs in the middle 70s to upper 80s. Temps will be a little cooler along the North Shore from Silver Bay to Grand Portage. Temperatures trend a bit warmer Sunday with highs in the low 80s in interior north-central Wisconsin to the low 90s in north-central Minnesota.
539 AM EDT Sat Aug 14 2021 A cold front will finally cross the region this morning, pushing the threat of showers and storms southward and ushering in cooler and more comfortable air. Broad high pressure will settle in on Sunday.
Regarding the morning update, the main thing I did was adjust PoPs downward through the remainder of the morning except for the in the higher terrain. Showers will develop earlier than normal (late morning) with a cold front moving into the region. McD Chattanooga Airport, TN 91 72 89 72 85 / 60 40 80 60 80 Knoxville McGhee Tyson Airport, TN 92 70 87 70 85 / 50 40 70 60 70 Oak Ridge, TN 90 71 86 71 83 / 50 40 70 60 80 Tri Cities Airport, TN 88 68 85 68 83 / 60 30 60 50 70.
By later this morning, the thick smoke will remain in place, keeping temperatures slightly cooler and the atmosphere slightly more stable. Some locations may end up warming up closer to guidance as the upper level ridge builds in a bit over northern California and southern Oregon. The other reason is that the upper level ridge is building in over northern California and southern Oregon. By Sunday, high pressure builds in over the region with some of the monsoon moisture dissipating. The lower levels of the atmosphere appear to dry out with some breezy winds over higher terrain Sunday afternoon and evening.
A cold front has shifted just south-southeast of our forecast area with cooler and less humid air filtering southward into our region.
This activity is occurring within the monsoonal moisture plume that is oriented southwest to northeast across the region and is expected to slowly move to the south today as the upper level ridge across the Great Basin expands to the southeast. With the continued cloudiness and rainfall this morning temperatures will struggle to warm much this morning which will keep afternoon temperatures on the cooler side as well. As such it seems like any minor disturbance in the weak ridge aloft could produce showers and thunderstorms on any particular day.
649 AM EDT Sat Aug 14 2021 Showers and thunderstorms will again be limited in coverage today as the upper level ridge begins retreating into the Atlantic this afternoon. Synoptic situation will begin slowly changing this afternoon as the upper level ridge which has been over the area begins retreating into the Atlantic Basin. High temperatures this afternoon will be in the mid 90s with lows tonight again in the low to mid 70s.
759 AM EDT Sat Aug 14 2021 A cold front will finally cross the region this morning, pushing the threat of showers and storms southward and ushering in cooler and more comfortable air. Broad high pressure will settle in on Sunday.
534 AM CDT Sat Aug 14 2021 Southerly flow will slowly increase today, but humidity values will still remain on the lower side. High pressure will continue to drift east with southerly flow at the surface remaining in place and above about 10 mph most of the night.
Upper level analysis places high over the Great Basin, with broad ridging to the north. For today, aforementioned ridge will be the dominating feature bringing very warm temperatures to our area.
245 AM PDT Sat Aug 14 2021 High pressure will remain over the region with dry and hot weather through Sunday. Cooler temps and showers mainly across the north will start out the first few days of the workweek. Today and Sunday: High pressure is expected to be in place over the region through late Sunday allowing the hot, dry pattern to continue with widespread smoke and haze. A transition is expected to occur late Sunday afternoon as a trough begins to press into the Pacific Northwest. The trough will bring breezy conditions to the Cascade Gaps, Okanogan Valley, and western portion of the Columbia Basin.
/issued 315 AM CDT Sat Aug 14 2021/ SHORT TERM (Now through Sunday): Weak 500 mb high pressure will persist over the BRO CWFA during the period.
318 AM MDT Sat Aug 14 2021 High pressure over the region will allow temperatures to warm into the 90s to near 100 degrees today with light winds over most areas. Expect to see an increase in wildfire smoke this evening from fires to the west as the ridge axis shifts east.
High temperatures this afternoon will be similar to yesterday's with highs in the mid to upper 90s along and north of I-10 and in the low 90s near the coast. Increased cloud cover on Sunday will keep afternoon highs down into the low 90s across the region.
615 AM CDT Sat Aug 14 2021 (Today and tonight) Early this morning, much of central Texas remained underneath an upper ridge that was breaking down due to a larger scale trough digging into the southern Plains.
629 AM EDT Sat Aug 14 2021 Upper air pattern consists of a 500 mb trough over the lower Great Lakes with a ridge over the Rockies. The trough will move to New England and a weak trough will develop over the Mississippi River valley with the ridge shifting to the western U. Quiet and warm weather is expected through mid-week with southerly flow returning to the area as ridging builds into eastern Canada.
As the day wears on, high pressure building in from the north should push the dry air into the entire forecast area and eliminate any further shower chances for the rest of the day, and bring clearing skies with it. High temperatures with the sunshine but cooler air advection should top out in the upper 70s to lower 80s, with dewpoints in the afternoon in the 50s. Given the high staying across the Great Lakes and not building south more into the Ohio valley, think the addition of some lower pops in the southern/southeastern counties for late tonight and through Sunday is reasonable. The work week will then feature a rather summery pattern as persistent weak southerly flow and a broad, modest mid-level troughiness just west of the region.
Tropical Cyclone Fred continues to move northward over the eastern Gulf of Mexico today. Highest chances for showers and storms this morning will remain along the coast and portions of the interior, with the highest storm coverage this afternoon shifting to across the western interior. Afternoon highs will be a little below average today with highs in the upper 80s to near 90 degrees due to the high cloud cover and heavy rainfall. Overnight lows will be in the low to mid 70s. Scattered to numerous showers and lightning storms expected to continue through today and into tonight as Tropical Cyclone Fred moves northward into the eastern Gulf of Mexico.
442 AM PDT Sat Aug 14 2021 High pressure will remain over the region with dry and hot weather through Sunday. Cooler temps and showers mainly across the north will start out the first few days of the workweek. Today and Sunday: High pressure is expected to be in place over the region through late Sunday allowing the hot, dry pattern to continue with widespread smoke and haze. A transition is expected to occur late Sunday afternoon as a trough begins to press into the Pacific Northwest. The trough will bring breezy conditions to the Cascade Gaps, Okanogan Valley, and western portion of the Columbia Basin.
446 AM MDT Sat Aug 14 2021 An upper level ridge centered roughly across Nevada and Utah will result in light west to northwest flow aloft. On Sunday, the upper ridge is progged to retrograde westward with light to modest northwest flow aloft. High temperatures are expected to be slightly cooler Sunday in most locations due to an increase in convection and the upper- high sliding westward, but still expecting above average temperatures both days. The dome of high pressure sitting to the west of the area will usher northwest flow over the CWA which will keep the area mostly dry with seasonal temperatures.
Today Through Sunday Night As of 09Z this morning, we remain situated in a soupy summer air mass with a weak cold front hung up across the Ozarks in southern MO. Abundant moisture and residual elevated instability ahead of the front, coupled with weak troughing aloft and transient impulses embedded within the trough, have supported continued shower activity overnight with some occasional lightning, particularly over southern sections where relatively stronger convection continues. Today, a stronger impulse embedded within the broader mid/upper trough will traverse the central Plains and finally push the cold front into AR later this evening. Some slightly drier air will try to filter in from the north late in the period, but without a more substantial push of cooler/drier air from the north, not expecting any noticeable change of air mass for most.
An area of scattered showers/embedded lighting was moving across the area this morning being aided by multiple outflow boundaries moving across the area in addition to the approaching inverted trof to our east.
745 AM EDT Sat Aug 14 2021 Showers and a few rumbles of thunder will continue through the morning hours as a cold front slowly tracks eastward. The well anticipated cold front is slowly trekking eastward and is now across northern New York. Temperatures will trend cooler behind the cold front, finally bringing relief to the heat and humidity that we've experienced this week. High pressure will then begin to encroach upon the region during the overnight hours and through Sunday.
311 PM EDT Sat Aug 14 2021 Pleasant warm day today with temperatures in the mid to upper 70s, low humidity and plenty of sunshine from high pressure centered over the Great Lakes.
Expect the highest concentration of convection through the early evening to continue to be across the south/west portion of the area. and the weakening of the subtropical ridge.
This, combined with the strengthening upper level ridge over the Great Basin, is boosting temperatures region-wide with most Valley communities running 5 to 10 deg F hotter compared to 24 hours ago. At night, smoke can act as a "blanket" and insulate, keeping low temperatures warmer than they ordinarily would be. As smoke coverage varies from hour-to-hour and from location-to-location, this introduces plenty of challenges with both the high and low temperature forecast. As a result of the building ridge, afternoon/evening shower and thunderstorm potential will be fairly limited in the mountains.
(This afternoon through Sunday night) An upper ridge is over the western part of the country while an upper trough is centered over the Midwest.
143 PM EDT Sat Aug 14 2021 Showers and a few rumbles of thunder will continue through the morning hours as a cold front slowly tracks eastward. Temperatures will trend cooler behind the cold front, finally bringing relief to the heat and humidity that we've experienced this week. High pressure will then begin to encroach upon the region during the overnight hours and through Sunday.
1249 PM CDT Sat Aug 14 2021 (Today and tonight) Early this morning, much of central Texas remained underneath an upper ridge that was breaking down due to a larger scale trough digging into the southern Plains.
217 PM EDT Sat Aug 14 2021 Cold frontal passage brings isolated to scattered storms into Sunday. By Sunday afternoon however, that frontal boundary will linger to our south as high pressure off the coast of the Atlantic pulls in moisture from the deep south. Short term characterized by upper ridge along east coast and troughing to our west, with a moist southerly flow across the area.
1139 AM MDT Sat Aug 14 2021 18Z TAF CYCLE Upper ridge axis stretched ewd and swd through CO and over nrn NM next 24 hrs, gradually suppressing the greatest moisture and precipition into far southern NM.
245 PM CDT Sat Aug 14 2021 At mid afternoon the cold front had slipped into northern Arkansas as northeast winds in its wake have been advecting in drier and more comfortable air. High pressure was centered over the western Great Lakes and this will continue to bring northeast winds and drier air into the region through Sunday.
334 PM EDT Sat Aug 14 2021 A cold front will push offshore tonight as high pressure builds in from the west.
134 PM EDT Sat Aug 14 2021 A crossing front will usher in cooler and more comfortable air for the remainder of the weekend. Cold front east of PGH will continue east and be east of the ridges by late afternoon. Broad high pressure will settle in on Sunday.
1209 PM MDT Sat Aug 14 2021 A low-amplitude ridge is positioned over the Intermountain West this weekend, with temperatures running about 5 degrees above normal. The dome of high pressure sitting to the west of the area will usher northwest flow over the CWA which will keep the area mostly dry with seasonal temperatures.
as expected as west coast ridge expands eastward. JKL High pressure over the region will allow temperatures to warm into the 90s to near 100 degrees today with light winds over most areas. Expect to see an increase in wildfire smoke this evening from fires to the west as the ridge axis shifts east.