Aikyam-Lab/Synoptic-Bench huggingface dataset:
A trough extending well to the NE of a westward moving upr low in the GOM will cross the area tomorrow, bringing increased chances for SHRA/TSRA to the region. Highs on Sunday will still likely climb into the upper 80s for most locations, with relatively high dew point values leading to heat indices in the low/mid 90s. An upper ridge pattern looks to be in place across the mid Atlantic Basin heading into the new work week, while high pressure at the sfc gradually moves swd into the srn Atlantic. The overall wx pattern then begins to turn more unsettled late in the period, as an upper trough axis drops swd across much of the ern CONUS and a cold front approaches from the NW.
Lots of OFB's around the CWA this evening, and much of the earlier, and ongoing, convection that has been able to stay on or close to these OFB's has been able to persist for longer than 30 to 45 minutes, within this low instability/NIL shear environment. The overall pattern of a 500mb ridge west, and trough over the Central and Northern Plains up through Hudson Bay remains.
The pattern will remain blocky through midweek with an elongated upper trough over the upper midwest. While there is no good synoptic trigger to trigger any widespread heavy rains, the downstream side of the trough will keep the chance for showers and thunderstorms in the forecast through midweek, with the best chances sliding a little to the east each day as the trough does the same. If it is able to move far enough west precipitation chances would remain through the weekend, but with the strong western ridge slowly advancing eastward it looks like the cutoff low would stay to far east to affect us much.
The subtropical ridge does look to start to break down by the end of the week, allowing the upper trough to finally progress into the eastern CONUS by the weekend. If this occurs, a break from the humidity should result as northwest flow sends cooler and drier air southward.
435 PM MDT Sat Jun 26 2021 WV imagery this aftn depicts a highly amplified ridge over the wrn CONUS, which is contributing to record heat over the Pac NW. Along the periphery of the ridge, several weak waves continue to carve out a broader trof over the cntrl CONUS. This trof and its embedded waves are leading to continued unsettled conditions over our region, with iso/sct showers/storms ongoing across the area this aftn.
Clouds are gradually dissipating over the region, as warmer air moves in from the north.
Ridging keeps weather quiet through the weekend, and a warming trend begins.
Meanwhile cool 60s persist along the Highway 1 corridor with a shallow fog deck from Bodega Bay to Pacifica and then again around Pebble Beach and Carmel Bay. We continue to watch a well defined upper low approach 38n/130w that will move eastward towards Cape Mendocino on Sunday but remain offshore. The upper low will shift north and rotate around the well advertised ridge that is bringing extreme heat to the Pacific Northwest.
No change was needed for the eve update The Upper Ohio River Valley is under the influence of a rain-suppressing high-amplitude ridge over the ern CONUS with split-flow troughing over the Midwest.
1053 PM EDT Sat Jun 26 2021 The area will remain in warm, humid air for several days on the western periphery of Atlantic High Pressure.
539 PM MDT Sat Jun 26 2021 WV imagery this aftn depicts a highly amplified ridge over the wrn CONUS, which is contributing to record heat over the Pac NW. Along the periphery of the ridge, several weak waves continue to carve out a broader trof over the cntrl CONUS. This trof and its embedded waves are leading to continued unsettled conditions over our region, with iso/sct showers/storms ongoing across the area this aftn.
653 PM CDT Sat Jun 26 2021 The forecast in the short term is primarily being driven by northerly flow on the downstream side of an anomalously strong PAC NW upper level ridge. The CWA sits under a plains trough with the main surface feature of note well south of the CWA. Showers have been noted on the KLNX radar much of the day with now some deeper convection being noted off the Pine Ridge and southeastern lee of the Black Hills. More of the same for Sunday as the region sits under the influence of broad troughing. In the extended there's fairly good agreement that the highly anomalous PAC NW Ridge will largely remain in place, though weaken slightly through the forecast period.
808 PM EDT Sat Jun 26 2021 Atlantic high pressure will direct an onshore flow into the area. An upper ridge centered near the Mid Atlantic coast will extend into the southeastern states. The lower moisture and lack of a trigger should result in lower rain chances.
The forecast area remains wedged between persistent troughing over the Upper Midwest and a ridge located over the southeast/Mid- Atlantic CONUS. Otherwise, it will be another warm and muggy night, with lows in the lower to middle 70s and mostly clear to partly cloudy skies.
The upper level trough will continue to sharpen today and tonight from the northern Plains south-southwest through New Mexico, and remain there through the short-term. An upper level low and associated tropical wave over the north-central Gulf of Mexico today will continue westward through the short-term. Highs temperatures on Sunday are forecast to be a few degrees cooler, influenced from a more easterly surface flow and shower activity.
The forecast in the short term is primarily being driven by northerly flow on the downstream side of an anomalously strong PAC NW upper level ridge. The CWA sits under a plains trough with the main surface feature of note well south of the CWA. Showers have been noted on the KLNX radar much of the day with now some deeper convection being noted off the Pine Ridge and southeastern lee of the Black Hills. More of the same for Sunday as the region sits under the influence of broad troughing. In the extended there's fairly good agreement that the highly anomalous PAC NW Ridge will largely remain in place, though weaken slightly through the forecast period.
An upper low and the attendant surface reflection will affect the area Monday. Today will be the last widespread dry day in the forecast thanks to strong ridging from the northeast maintaining dry air aloft and decent subsidence inversion seen in forecast soundings. Nonetheless, weakness in mid and upper ridging along with increased instability Monday will allow for scattered showers and thunderstorms to develop, with best chances across southern counties. Bermuda high pressure will extend into the area from the east through the period as an upper low moves away to the west.
For the boundaries, dryline located over eastern New Mexico and cold front near a Lubbock to Childress to Enid OK line. Mild lows for tonight and cooler weather for Sunday but still humid in the morning.
845 PM PDT Sat Jun 26 2021 High pressure aloft will keep the weather hot inland through Monday. The low clouds should fill back in along the immediate coast overnight, but may not spread as far inland as last night. An extensive omega block currently dominates the pattern over the west coast, with a high centered over British Columbia, another high centered about 350 miles to our southwest, and extensive trough extending across the Rockies to the desert southwest and a low centered about 630 miles west of San Francisco.
An area of High pressure is building over the region and expected to bring a period of extreme high temperatures across the Pacific Northwest.
SHORT TERM (Now through Monday): An inverted 500 mb trough with embedded closed low will gradually retrograde towards and over the BRO CWFA during the period.
However the low level jet is centered off to the east of the CWA and our area is generally in the divergent part of that feature.
The pattern will remain blocky through midweek with an elongated upper trough over the upper midwest. While there is no good synoptic trigger to trigger any widespread heavy rains, the downstream side of the trough will keep the chance for showers and thunderstorms in the forecast through midweek, with the best chances sliding a little to the east each day as the trough does the same. If it is able to move far enough west precipitation chances would remain through the weekend, but with the strong western ridge slowly advancing eastward it looks like the cutoff low would stay to far east to affect us much. Think clouds in the 8k to 10k foot level will help keep the lower levels relatively clean.
Today As low pressure passes through Wisconsin into Michigan today, northwest winds behind a weak surface front will advect slightly drier air into the region. Dewpoints are forecast to fall into the low 60s NW to upper 60s SE, which is 5+ degrees lower than the past several days. There are indications that the upper level high on the east coast will break down the second half of the week and bring an end to the wet pattern. Right now the model consensus has the highest pops along and east of the Mississippi.
Like yesterday, this activity will begin to diminish mid to late morning as the low level jet weakens. The potential for showers and storms will continue through the week even as the upper level trough over the region gets nudged out of the area through mid-week by the mid-Atlantic ridge building to the west. Late in the week, a cold front is expected to move into the area as a large upper level trough is carved out across the eastern US.
The trough axis will pass to the west of our area Monday morning, leaving us on the Gulf inflow, wet side of the wave Monday afternoon and evening.
Today Through Monday Night To begin the period, a cold front is located just to our west over parts of the Central Plains associated with an upper level trough. This approaching cold front has been slowed down by the high pressure to our east that does not seem to be budging. In the short term, PoPs will be the highest that they've been all week with higher PoPs focused mainly in the northwest. QPF seems to indicate that over the next couple of days these rain showers might produce light to moderate rain with the highest QPF in the CWA being in NW AR. High temperatures look to climb up into the high 80s to low 90s with heat index values slightly higher. However, it appears temperatures will be slightly cooler than previous days due to increase cloud coverage and rain showers.
Latest analysis shows a positive tilted trough over the central part of the country with a surface front stretching from the southern plains up to the Great Lakes region. Meanwhile to our east, an upper level high continues to build in from the east. Forecast soundings show plenty of dry air at the low levels and aloft so it will be tough for any convection to develop, but do have pops around 10% this evening to account for the small possibility. Initially, two very stout ridges, one located near the Oregon/British Columbia region, and the other centered off of the Mid-Atlantic coastal region, will be dominating. In between these two features, a positively tilted trough will be aligned from Hudson Bay down through the Upper Midwest and through the Desert Southwest.
A large dome of high pressure will continue to be situated over the Pacific northwest through the short term. Our forecast area will be on the eastern edge of this ridge today which will result in a northerly flow aloft. The large dome of high pressure will begin to shift east Monday resulting in rising heights, dry conditions, and warmer temperatures.
An upper level trough moving into the Plains and a surface frontal boundary approaching the state from the NW will be slowed down by high pressure to our east. The upper high over the eastern CONUS and western Atlantic will continue to build and expand westward over the next few days.
Any showers will end early this evening and then return to the coast late tonight ahead of the next inverted trough in the easterly flow.
With regards to our area, expect the best coverage and the highest rainfall totals to be across the Big Country where the cold frontal boundary will generally be located. Otherwise, expect cooler conditions across the Big Country. This area will be in the low to mid 80s as a result of the cold frontal passage. However, areas south of there will remain in the lower 90s this afternoon.
Upper trough axis has shifted slightly eastward and is currently centered from western Minnesota south-southwestward into eastern SD and down into the central Great Plains. Upstream, an anomalous upper ridge continues to exert its influence over the Pacific NW. One final day of showery and near-normal temperatures are expected Monday before the upper trough axis pivots eastward and the upper ridge noses into the Northern Plains.
339 AM EDT Sun Jun 27 2021 High pressure will extend from north of Bermuda westward into the Southeast and southern middle Atlantic, with associated easterly flow off the Atlantic, through early this week. High pressure at the surface and aloft will continue to extend into central NC from off the Mid-Atlantic coast, resulting in a continued fetch of southeast/easterly flow. This coupled with the mid level ridge axis extending westward and across the area from offshore will result in lower chance for showers and storms.
216 AM CDT Sun Jun 27 2021 Upper trough over the Plains and the boundary extending from the southern Plains towards the Great Lakes continues to keep most of the showers and thunderstorms off to our northwest. The upper high which has kept us mainly dry over the past few days will start to lose its grip today, and we may see some isolated showers and thunderstorms especially east of I-65 in the afternoon, largely diurnally forced.
A cold front will move through the region late in the week. Temperatures will be a few degrees warmer than yesterday. Deeper moisture rotating around a ridge centered off the mid Atlantic coast will push into the region late tonight and tomorrow. Temperatures, both lows and highs, will be near if not a shade warmer than persistence.
GKendrick A large upper level blocking pattern will remain in place for at least the first half of this week.
Upper level high pressure stretches from the east coast westward into the Mid-South. Upper level high pressure strengthens across the area today which will suppress most of the afternoon convection though certainly cannot rule out an isolated storm here and there.
An upper ridge stretches southwest over Southeast through the Near Term. An upper level trough over the north-central Gulf of Mexico moves off to the west, as another over the eastern Caribbean moves west along the southern periphery of the upper ridge. 5" ahead of the inverted trough approaching from the Caribbean. With the higher chances of rain Sunday counters the weak subsidence from the upper ridge over the Southeast, and temperatures topping out on the cool side of seasonal norms are expected.
The complex that brought heavy rainfall to much of the region yesterday is slowly making its exit early this morning, with a trailing deformation zone and multiple embedded lower tropospheric waves rotating around the cyclone center helping to prolong the precipitation threat. With more sunlight working through the clouds and little change to the lower tropospheric airmass, highs today should push the upper 70s to around 80 in a few spots.
428 AM EDT Sun Jun 27 2021 High pressure will extend from north of Bermuda westward into the Southeast and southern middle Atlantic, with associated easterly flow off the Atlantic, through early this week. Water vapor satellite showed an upper-level ridge off the Delmarva coast, and an upper-level trough across Plains. Surface observations showed high pressure centered NE of Bermuda, with ridging across the Southeast. Dewpoints in the low 70s this morning will lower to the upper 60s this afternoon as mixing occurs, however the heat index will still make it feel like the low to mid 90s this afternoon. The upper ridge to our northeast will continue to build Monday, increasing high temperatures a degree or two for most areas compared to highs today.
1135 PM MDT Sat Jun 26 2021 WV imagery this aftn depicts a highly amplified ridge over the wrn CONUS, which is contributing to record heat over the Pac NW. Along the periphery of the ridge, several weak waves continue to carve out a broader trof over the cntrl CONUS. This trof and its embedded waves are leading to continued unsettled conditions over our region, with iso/sct showers/storms ongoing across the area this aftn. Cannot rule out another round of showers/storms on Monday as another shear axis rounds the ern periphery of the ridge and crosses the nrn Plains. Beyond Monday, however, chances for precip dramatically decrease as warmer, drier air mass begins to overspread the area from NW-SE.
Today through Sunday afternoon Strong and highly amplified upper ridge is now firmly in place in the West. A weak cut-off Low will be meandering off of the California coast through the short term period but is not expected to be able to penetrate eastward into the strong ridge. Continued warming on Monday will allow Humboldt County to soar into the low to mid 100's.
An upper level trough remains stalled from east of the Four Corners Region northward through the Central Plains into the Great Lakes Region. Most unstable CAPE in the lowest 3km will peak at only 400-800 J/kg. With skies turning partly cloudy, lows will range in the low to mid 50s. The upper trough will remain over the region, although height rises are indicated. An upper ridge will remain centered over the Pacific Northwest and across the Southeastern U.
Aloft, an fairly tight upper level low continues to move westward across the Northwest Gulf this morning. For today, the upper level low will continue to move westward, bring additional moisture and lift later this morning and afternoon across most of the region.
327 AM CDT Sun Jun 27 2021 Today and tonight: Early morning water vapor imagery showed the circulation around an upper level low spinning in the northwest Gulf and around a mid level ridge to the northeast that will remain dominant over our region through tonight. Early morning surface analysis still had a >1016mb ridge nosing across our CWA from the east. The combined affects of ridging surface and aloft our our northeast is expected to inhibit convection there again today but afternoon heating and the increase in moisture across the south is expected to lead to at least scattered coverage south of Interstate 20. Highs today should reach into the lower 90s at most sites and most sites tonight will bottom out in the lower 70s again.
There is a consensus amongst the 00Z guidance that most of the energy within the Plains upper trough will lift northeast into Canada through Monday.
In the upper levels, strong ridging remains over the East Coast and Southeast states. A trough is over the Central U. High pressure remains over the region today and tonight with light southerly low level winds.
Quite a bit of cloud cover across the region today ahead of weak upper trough axis to our northwest. This weak trough across the Dakotas will be our main weather player the next few days into about midweek.
A trough remains over the Tri-State area today with northerly flow over the Nebraska Panhandle. High pressure remains over the PAC NW with a ridge firmly in place over British Columbia. This pattern will change little over the next few days resulting in some cooler temperatures persisting through the Tri-State area and isolated chances for showers and storms. Highs today and tomorrow will range from the low 70s in Eastern Colorado to mid-80s in the eastern part of the Tri-State area. At the start of the period, a weakening upper trough extends from the Upper Midwest to the High Plains, with a ridge to the west. In addition, an area of high pressure prevails over the east coast.
Upper ridging will then build across the western U.
Monday looks dry and warmer in the west. Flow across Wyoming will be more northeasterly as the trough to the east and ridge to the northwest maintain their positions.
The position of the upper low will create divergent upper level winds and moisture levels increase to around 2. Will likely also need to continue the high rip current risk on Sunday.
McD Chattanooga Airport, TN 89 71 91 70 89 / 30 10 20 10 40 Knoxville McGhee Tyson Airport, TN 89 70 91 69 91 / 30 10 30 10 40 Oak Ridge, TN 88 69 91 69 91 / 30 10 30 10 30 Tri Cities Airport, TN 88 66 89 65 90 / 30 10 30 10 30.
251 AM EDT Sun Jun 27 2021 Central CONUS troughing and east coast ridging remain largely unchanged throughout the short term, though the 5H ridge is progged to build slightly over the OH Valley. CAMs do show a chance of very isolated showers over the CWA this afternoon, but aforementioned building high pressure aloft should keep most areas dry. Thickness values slightly increase from yesterday, so expect afternoon max temperatures will be a degree or two warmer today. Another quiet night is expected with Monday morning min temperatures in the low 70s. Large Atlantic ridge that has kept our weather dry the past few days will slowly get squeezed by an upper low moving in from the northern Gulf coast and an trough dropping into the Midwest.
/Today through Monday/ Upper-air pattern today continues to feature some form of an Omega Block with a strong ridge along the U. /Canada border in the Pacific Northwest, with additional ridging over the eastern CONUS with a trough across the central CONUS. The upper-level trough and stalled frontal boundary will increase instability across the region today. The aforementioned upper-level pattern will continue through the day on Monday with the ridge across the Pacific Northwest slowly pushing east. Upper trough will remain in place from the Ontario Province in Canada southwestward into New Mexico. This trough will slowly progress towards the east through the day Monday.
Today: The upper level trough is still in place over the central CONUS.
347 AM EDT Sun Jun 27 2021 The area will remain in warm, humid air for several days on the western periphery of Atlantic High Pressure.
In fact, this morning's satellite imagery looks fairly similar to yesterday morning's with a MCS over the southern Plains and an upper low spinning over the Gulf of Mexico. Skies should clear out tonight, but overnight temperatures will remain mild in the lower 70s. Some patchy fog may be possible in areas that see rain today, but have left it out of the current forecast package given the low confidence in it occurring.
1145 PM CDT Sat Jun 26 2021 A warm and humid night is in store across central Illinois with low temperatures only dropping into the lower to middle 70s. The subtropical ridge does look to start to break down by the end of the week, allowing the upper trough to finally progress into the eastern CONUS by the weekend. If this occurs, a break from the humidity should result as northwest flow sends cooler and drier air southward.
Another weak disturbance in northerly flow will then re-amplify the broad trough pattern across the region today. Broad trough influence could linger across southern and eastern portions tonight, perhaps bringing some lingering showers to these areas. The broad trough could be slow to exit the region on Monday. A highly amplified ridge of high pressure then looks to build across the western US for much of the upcoming week. The large scale of this ridge could spread into much of ND bringing warming and drying conditions to the state.
The region remains under southeast flow at the mid levels as the area is between an inverted trough over the Gulf and ridging off the Carolina coast. The inverted trough retrogrades westward tonight into tomorrow with ridging building in across the region. Highs will be in the upper 80s to lower 90s with lows in the lower 70s. The latter is where the highest PoPs (chance-to-likely) reside. High temperatures are forecast to be in the low 90s, with lows in the low 70s.