Aikyam-Lab/Synoptic-Bench huggingface dataset:
DCAPE values are expected to decrease into the low 100s this evening, which with a backing wind profile, confidence is low for any severe threat. The region is expected to remain under NW flow aloft as the ridge builds again over the western CONUS and slowly pushes east. as the mid-latitude westerlies shift northward in response to height rises assoc/w an amplifying ridge over the Desert Southwest, southern/central Rockies, and southern/central Plains.
On Monday, moisture and PGFs will increase ahead of an approaching cold front which will prompt low VFR cu and sly/swly flow in the 8-12kts range with low end gusting possible. CDG Chattanooga Airport, TN 72 88 69 80 62 / 10 60 90 60 10 Knoxville McGhee Tyson Airport, TN 72 89 67 77 60 / 10 60 90 60 10 Oak Ridge, TN 70 88 65 77 58 / 10 70 90 50 10 Tri Cities Airport, TN 67 88 65 75 56 / 20 50 80 60 10.
Lows will only bottom out in the lower 70s for most area, with upper 60s possible along the Cumberland plateau, Sand/Lookout/Brindley Mtns. Then, as the front and larger amplitude trough approaches from the northwest, pre-frontal convection shows up in a few of the CAMS, with coverage expanding during the late afternoon into the early evening hours.
244 PM CDT Sun Jun 20 2021 A strong cold front will push into the region from the northwest tonight. Scattered showers and a few storms will linger behind the front on Monday, along with much cooler temperatures. All severe modes would be possible given nearly 3k J/kg MLCAPE and strong deep layer shear near 50kt, but with the warm front located farther north near I-80, damaging winds and hail are primary threats. A line of thunderstorms is expected to develop ahead of a cold front across eastern Iowa early this evening, then push into the northwest CWA towards mid evening. This combined with mostly cloudy skies should limit highs to the low and mid 70s.
Ridging aloft quickly builds in TUE-THU with highs back into the 90s.
VFR conditions expected for most of this TAF cycle, but a cold front will begin moving into the area towards the end of the period.
647 PM CDT Sun Jun 20 2021 Southerly winds 5 to 10 knots tonight to become southwest on Monday ahead of a cold front that will bring showers and thunderstorms to area terminals from 21/17Z-21/23Z. A strengthening southwesterly low-level jet in the vicinity of a weak upper trough over Southeast Texas/Southwest Louisiana should result in another round of showers and thunderstorms prior to sunrise Monday south of Interstate 20. Farther to the north, an upper trough axis diving southeast across the Plains will help to push a cold front towards the area. Despite only modest deep layer shear, some of the higher resolution CAMs suggest some rather explosive thunderstorm development south of Interstate 30 during the late afternoon through early evening in an environment with CAPE values in excess of 3000-3500 J/kg and steep lapse rates.
A cold front was located over eastern Nebraska into western KS. Main focus in the short term will be with shower and thunderstorm chances later tonight into Monday and with cooler temperatures moving in. South central MO will have the highest readings around 80 before the front moves through. The rain should exit the area by Monday evening and with the cooler and drier air mass continuing to move into the region, temperatures will dip into the upper 40s to low 50s for lows.
Southwest winds around 5 mph overnight under mostly cloudy skies, with overnight lows in the low to mid 70s. Coverage of showers and storms will decrease overnight, with the highest coverage across the Treasure Coast offshore waters before midnight.
430 PM MDT Sun Jun 20 2021 The C-O-L-D F-R-O-N-T remains hung up along the Continental Divide, but will start moving farther south later this afternoon, being nudged southward by the next piece of the H5 trough moving in from the northwest. Behind the front, temperatures will definitely feel much cooler, with lows tonight in the 40s for the lower elevations, and widespread temperatures near freezing for higher elevations, including Yellowstone NP. The rainfall will be moving east late tonight as high pressure moves in. Monday will be a great day across Wyoming, with high pressure dominating the sfc and aloft.
Visible satellite imagery is showing clear sky across the majority of the region outside of a narrow scattered cu field focused along the surface cold front over northcentral Kansas into southeast Nebraska. The cold front is expected to continue pushing southward across our area exiting the area early this evening, so in the meantime the area along the boundary, basically southeast of Dodge City will need to be monitored for any surface convergence and heating triggered thunderstorms for which there may easily be a localized hail risk.
520 PM CDT Sun Jun 20 2021 A strong cold front will push into the region from the northwest tonight. Scattered showers and a few storms will linger behind the front on Monday, along with much cooler temperatures. All severe modes would be possible given nearly 3k J/kg MLCAPE and strong deep layer shear near 50kt, but with the warm front located farther north near I-80, damaging winds and hail are primary threats. A line of thunderstorms is expected to develop ahead of a cold front across eastern Iowa early this evening, then push into the northwest CWA towards mid evening. This combined with mostly cloudy skies should limit highs to the low and mid 70s.
Conds will deteriorate from N to S beginning as early as Monday morning as a cold front pushes through the region. Winds will start out S/SWrly, becoming W/NWrly behind the cold front later in the period. Later tonight/early Monday, low clouds will increase as a cold front approaches from the northwest.
A lull in the shower and storm chances is expected for a time late this evening and early overnight, but more showers and storms are expected overnight in association with an approaching cold front. Cooler and drier air will then settle in Monday through the middle of the week. A second line of convection is still expected to develop along a cold front in eastern IA/WI this evening, with the bulk of CAMs bringing this east in the 5-9z Monday AM time window. Expectations at this time are for this higher end gusts within the weakening MCS/QLCS to be more isolated and confined to areas mainly west of Interstate 69. A few showers may linger into Monday morning before the cold front exits to the east, especially along/east of I-69. Gusty northwest winds and cooler otherwise into the afternoon.
/Tonight through Sunday/ 21Z SEVERE THREAT UPDATE FOR TONIGHT: Low pressure has moved into southeast Minnesota with the cold front just entering far northwest Iowa and an upper-level jet streak entering southern Minnesota and NW Iowa. The low is expected to continue to track eastward across southern Minnesota through the afternoon hours bringing the cold front with it passing northwest to southeast through Iowa this afternoon into evening. CAMs still hint that storms will initiate along and ahead of this approaching cold front.
603 PM MDT Sun Jun 20 2021 Northwest flow will prevail over eastern Utah and western Colorado through the short term period as the area of high pressure remains centered over southwest Arizona and as a broad upper level trough dominates the central CONUS. 700mb temperatures will drop by some 3 to 5 degrees C which at the surface will translate to highs 4 to 8 degrees cooler on Monday. Monday will see the upper level gradient relax somewhat as the ridge of high pressure starts building back into the area from the southwest.
A cold front will enter northeast OK around 08-09Z and should clear the KMLC/KFSM sites after 16Z. /Issued 307 PM CDT Sun Jun 20 2021/ The much advertised cold front is still on track to bring much cooler.
A ridge axis will remain across South Florida with increased moisture across the region due to a southerly to southeasterly wind flow. High temperatures will be in the low to mid 90s, with heat indices soaring into triple digits today.
Temperatures across the island communities are in the lower to mid 80s and the dew point values are in the mid 70s. The broad subtropical ridge centered over the central Atlantic extends to the eastern Gulf of Mexico, keeping the Florida Keys on a weak southerly flow. Temperatures are expected to drop a few degrees overnight, settling into the lower 80s.
Otherwise, expect scattered showers and storms to continue through the late evening as short wave trof and cold front move through. Kavinsky (Issued 446 PM CDT Sun Jun 20 2021) Tonight and Monday: Widespread rain and clouds continue to hold back any potential instability ahead of approaching low pressure and associated cold front. Any showers/storms that do survive through southern Wisconsin are expected to exit to the east by 12 or 1 am as the cold front pushes through. Cooler temps aloft and the lingering clouds will result in temps not getting out of the 60s most locations, though a few places east may crack 70.
/issued 240 PM CDT Sun Jun 20 2021/ SHORT TERM (Now through Monday Night): Upper level moisture courtesy of of Tropical Depression Dolores and a 500 mb trough will continue to provide a chance of showers and thunderstorms across central and eastern portions of deep south Texas this evening. The 500 mb trough that is draped across east Texas will begin to shift eastward tonight into Monday and slightly drier air will begin to filter in. Monday night, a cold front will move into central Texas, but remain well north of the CWA. Overnight conditions tonight and Monday will remain sultry with lows generally in the low 80s.
350 PM MDT Sun Jun 20 2021 Northwest flow will prevail over eastern Utah and western Colorado through the short term period as the area of high pressure remains centered over southwest Arizona and as a broad upper level trough dominates the central CONUS. 700mb temperatures will drop by some 3 to 5 degrees C which at the surface will translate to highs 4 to 8 degrees cooler on Monday. Monday will see the upper level gradient relax somewhat as the ridge of high pressure starts building back into the area from the southwest.
Some adjustments to sky trends made, but so far expectation is still towards mostly clear to partly cloudy conditions and cooler temps. Expect all activity to end with sunset, aided by increasing subsident behind mid level trough axis already spreading southward over our CWA. Widespread light to moderate rainfall continues to work its way toward north-central MN on the head of a mid level s/w trough this afternoon. Scattered showers closely follow behind this deformation zone precip, owing in part to the H7 cold front/CAA. A dry, cool air mass moves into the area amidst northerly flow tonight noted by dew points dropping into the lower to mid 30s. CAA from the post frontal air mass will still make for a cool Monday morning with lows in the lower 40s and a lingering breeze.
306 PM MDT Sun Jun 20 2021 The C-O-L-D F-R-O-N-T remains hung up along the Continental Divide, but will start moving farther south later this afternoon, being nudged southward by the next piece of the H5 trough moving in from the northwest. Behind the front, temperatures will definitely feel much cooler, with lows tonight in the 40s for the lower elevations, and widespread temperatures near freezing for higher elevations, including Yellowstone NP. The rainfall will be moving east late tonight as high pressure moves in. Monday will be a great day across Wyoming, with high pressure dominating the sfc and aloft.
For tomorrow, the highest rain and thunderstorm chances will be over the interior and northern portions of South Florida. A ridge axis will remain across South Florida with increased moisture across the region due to a southerly to southeasterly wind flow. High temperatures will be in the low to mid 90s, with heat indices soaring into triple digits today.
634 PM CDT Sun Jun 20 2021 Main concern in the short term is the potential for strong to marginally severe convection this evening in the vicinity of the slow moving surface cold front.
806 PM CDT Sun Jun 20 2021 A strong cold front will push into the region from the northwest tonight. Scattered showers and a few storms will linger behind the front on Monday, along with much cooler temperatures. Thunderstorms continue to increase in coverage along and ahead of an advancing cold front in IA/MO this evening. All severe modes would be possible given nearly 3k J/kg MLCAPE and strong deep layer shear near 50kt, but with the warm front located farther north near I-80, damaging winds and hail are primary threats. A line of thunderstorms is expected to develop ahead of a cold front across eastern Iowa early this evening, then push into the northwest CWA towards mid evening. This combined with mostly cloudy skies should limit highs to the low and mid 70s.
909 PM CDT Sun Jun 20 2021 The cold front has advanced across nearly our entire forecast area at this time, excepting a few counties in the southeast, and storms have cleared out for the time being.
525 PM MDT Sun Jun 20 2021 Current surface analysis shows one cold front well south of the region, with a secondary cold front moving into northern portions of the area now. Upper level analysis shows trough moving through the Northern Plains, with upper level jet from the Northern Rockies into portions of SD and NE. Much cooler air has settled across the area, with temps in the 60s and lower 70s. Cooler conditions will prevail through Monday as Canadian high pressure slides southeast over the area. Lows will drop into the 40s in many areas, with some 30s over the higher Black Hills.
Temperatures will increase several degrees on Monday as an upper level ridge moves overhead.
529 PM MDT Sun Jun 20 2021 Current surface observations across the region show the stationary cold front near the Snowy Range and Sierra Madre Range across southeast Wyoming, with the boundary extending southward along the Front Range foothills across Colorado. This feature will continue digging southeast into southern and eastern Wyoming over the next several hours, which will eventually force the cold front south into Colorado tonight. Monday will be pleasant as a drier and cooler airmass moves into the region. Highs will struggle to reach the mid 70s across most areas with locations along I-80 likely remaining in the low 70s.
This activity was ahead of a the main cold front. and along the western periphery of the low level jet that extended eastward across Missouri. though the greater potential should remain north of the CWA within the axis of the low level jet. the cold front is still expected to move into Northeast Oklahoma late tonight with scattered showers and thunderstorms across parts of Northeast Oklahoma and Northwest Arkansas mainly after 08-09z. These storms may develop along/near a pre- frontal wind shift ahead of the true cold front with gusty northerly winds behind the boundary. Behind the cold front.
Latest satellite imagery shows the cold front extending from the TX/OK Panhandles northeast into Northwest Missouri. DCAPE values are expected to decrease into the low 100s this evening, which with a backing wind profile, confidence is low for any severe threat. The region is expected to remain under NW flow aloft as the ridge builds again over the western CONUS and slowly pushes east. as the mid-latitude westerlies shift northward in response to height rises assoc/w an amplifying ridge over the Desert Southwest, southern/central Rockies, and southern/central Plains.
Expect all activity to end with sunset, aided by increasing subsident behind mid level trough axis already spreading southward over our CWA. Widespread light to moderate rainfall continues to work its way toward north-central MN on the head of a mid level s/w trough this afternoon. Scattered showers closely follow behind this deformation zone precip, owing in part to the H7 cold front/CAA. A dry, cool air mass moves into the area amidst northerly flow tonight noted by dew points dropping into the lower to mid 30s. CAA from the post frontal air mass will still make for a cool Monday morning with lows in the lower 40s and a lingering breeze.
Meanwhile broad mid level troughiness from Hudson Bay to the Gulf of Mexico this evening eases eastward Mon. with a few weak short wave troughs sliding aloft the north-central and northeast Gulf waters. At the surface Atlantic high pressure stretches west to cover most of the Gulf of Mexico. Some daytime heating along with the short wave troughs will support numerous showers and scattered storms over the interior Mon afternoon. A high pressure ridge axis across south FL slowly lifts north over the state with prevailing flow backing from southwest and west to southeasterly.
Then, as the front and larger amplitude trough approaches from the northwest, pre-frontal convection shows up in a few of the CAMS, with coverage expanding during the late afternoon into the early evening hours.
647 PM CDT Sun Jun 20 2021 (This evening through Monday) A cold front will enter northwestern OK later this afternoon and pass through southeastern OK by late Monday afternoon. Scattered showers and thunderstorms are expected this evening in northern OK, given the high temperatures and convergence along the front. These will be aided by the southern edge of a large-scale mid- level trough moving through the upper Mississippi River valley/lower Missouri River valley.
351 AM CDT Mon Jun 21 2021 (Issued 351 AM CDT Mon Jun 21 2021) Today through Tuesday: Much cooler air arrives will arrive today behind the cold front. With cooler temperatures aloft and linger cloud cover, high temperatures are expected to only climb into the mid to upper 60s today and overnight lows tonight are expected to fall into the 40s. Gusty northwesterly winds will linger through this afternoon before high pressure builds into the area. Temperatures will rebound quickly on the back side of the high, so this cooler weather will be short lived.
325 AM CDT Mon Jun 21 2021 Key Points: -High temperatures today are expected to be 10-15 degrees below normal following a strong cold front that moved through the region overnight.
As the upper-level trough over the Great Lakes departs eastward Tuesday, 850 mb flow will slowly shift to southwesterly, allowing WAA into the Northern Plains.
That said, deep layer bulk shear increasing to around 40 knots, mixed layer CAPEs 1000 to 2000 J/kg and approaching cold front and sharp upper trough support the convection holding together a bit more than the CAMs suggest and therefore keeping high PoPs in.
Tuesday winds will be lighter, however surface dewpoints will remain in the 40s and temps will be a little warmer compared to Monday resulting in even lower humidity (15 to 25 percent).
334 AM CDT Mon Jun 21 2021 Much cooler weather is expected across the area to start the week with high temperatures today and Tuesday in the 70s. A large upper trough stretched from central Canada into the central CONUS will continue to drive the weather over the next 12-18 hours. Surface analysis depicts a northeast to southwest oriented cold front located from approximately Danville to Litchfield as of 3 AM. The cold front will work it's way through the area this morning, bringing a period of gusty northwest winds behind it as the pressure gradient quickly tightens. Temperatures will be in the 70s today, which is about 10-15 degrees cooler than normal for late June standards.
Clouds should spread back over all of Central Alabama overnight tonight as deep southerly flow returns out ahead of the longwave trough and associated surface front expected to arrive by Tuesday.
246 AM CDT Mon Jun 21 2021 Cold front has begun to enter northeast Oklahoma early this morning and is expected to move steadily southeastward through the morning hours. Lows in the low 50s and upper 40s will be common by Tuesday morning. Southerly winds quickly return on Tuesday though as mid level ridging begins to build back into the region.
Today Through Tuesday Night Early this morning, surface observations were showing a cold front invof the I-44 corridor of southwest Missouri and northeast Oklahoma. Broader depiction of the longwave pattern shows mid and upper level troughing over the central conus pushing the front southward. With the flow highly amplified and ridging over the gulf splitting in two, the front should have no problem moving all the way through Arkansas today. Precip should diminish during the evening hours as cooler and drier air advects in.
1219 AM CDT Mon Jun 21 2021 Main concern in the short term is the potential for strong to marginally severe convection this evening in the vicinity of the slow moving surface cold front. The relief from the heat will be short lived as upper ridging builds mid week. Summer returns mid week as upper ridging gets underway across the Plains brining 90s and 100s temps back to the area.
Better rain chances exist with incoming cold front late tonight, which should spread SHRA/TSRA to KCHA and KTYS just before 06z and possibly around or just after at KTRI. CD Chattanooga Airport, TN 88 69 78 60 84 / 90 100 60 10 10 Knoxville McGhee Tyson Airport, TN 89 66 75 59 83 / 90 90 70 10 10 Oak Ridge, TN 88 64 75 56 81 / 90 100 60 10 0 Tri Cities Airport, TN 88 64 73 54 81 / 80 90 80 10 10.
344 AM EDT Mon Jun 21 2021 Thunderstorms, potentially strong to severe, are expected this afternoon and early evening with a crossing cold front. Showers will linger into Tuesday morning, with cooler and drier conditions expected thereafter. Dry, but warmer weather will continue through the work week. Latest CAM runs suggest the cold front will bisect the forecast area around 00z this evening.
For tomorrow, the highest rain and thunderstorm chances will be over the interior and northern portions of South Florida.
The day today starts off with the cold front continuing to move SSE out of the area. This will make way for higher pressure at low levels, and upper level ridging just off to the west that will work its way across the CONUS through late Wed. With dwpts generally in the 40s this will still feel warm, but much cooler than the temps and mugginess felt as of late. Tuesday evening, a brief trough of low pressure crossing over the Rockies will try to initiate storms as it crosses the region. As mentioned in the short term, upper level ridging will dominate through mid-week.
1034 PM MDT Sun Jun 20 2021 The C-O-L-D F-R-O-N-T remains hung up along the Continental Divide, but will start moving farther south later this afternoon, being nudged southward by the next piece of the H5 trough moving in from the northwest. Behind the front, temperatures will definitely feel much cooler, with lows tonight in the 40s for the lower elevations, and widespread temperatures near freezing for higher elevations, including Yellowstone NP. The rainfall will be moving east late tonight as high pressure moves in. Monday will be a great day across Wyoming, with high pressure dominating the sfc and aloft. After a couple of cooler days the heat will return on Tuesday as a transitory ridge moves over the area. Highs will likely peak in the low to mid-90s across the lower elevations, or about 10 to 15 degrees warmer than normal.
257 AM CDT Mon Jun 21 2021 GOES East water vapor at 2am showing a deep level long wave trough digging out across the Northern Plain/Upper Mississippi/Great Lakes regions. At the surface, a deep low pressure system (995mb) was centered just north of Green Bay WI. Gusty northwest winds were in place across our area on the backside of this low with peak gusts within the last hour generally in the 25 to 30 mph range. High pressure builds in tonight with mostly clear skies.
Models show a ridge and associated high pressure over the NW Atlantic, with its western edge still weaken by the influence of Claudette over the eastern seaboard. By Tuesday, the influence of Claudette diminishes and allows for the ridge and high pressure over the W Atlantic to strengthen a little, with its western edge backing winds across SoFlo to a more SE flow. High temperatures remain hot with much of SoFlo in the low to mid 90s each day, and heat indices again hitting triple digits at times.