Aikyam-Lab/Synoptic-Bench huggingface dataset:
An upper level high across the south central CONUS will slowly move eastward the remainder of the week.
Steering flow aloft is more favorable than it has been in prior days as the upper high has shifted into the Big Bend of Texas, helping to enhance northwest flow aloft. The highest confidence of where this may happen is with KGUY (05/21Z-06/03Z) and KDHT (06/00Z-06/05Z) where VCTS has been included as the prevailing condition. An upper level ridge of high pressure near the four corners region is progged to gradually slide eastward this week and eventually become recentered over central Texas south of the OK and TX Panhandles by the upcoming weekend. Given the predicted upper level steering flow pattern, the highest probabilities for showers and thunderstorms were placed in the northwest sections of the forecast area, with the overall lowest values in the southeast Texas Panhandle.
256 PM MDT Mon Aug 5 2019 Highly anomalous ridging over Alaska has allowed lower heights to drop into the central Canadian Provinces. though stronger height falls to the North will keep the ridge suppressed instead of amplifying it back into the Canadian Rockies as has been the pattern lately. Temperatures not quite as cool tonight but with dewpoints going downward will trend toward or just below the lower guidance numbers.
A typical summertime synoptic pattern continues across North America with a stout upper-level ridge over the Southwest. The upper-level ridge will strengthen over the next few days, with the axis of this ridge moving to the east.
754 PM PDT Mon Aug 5 2019 High pressure returns with warming temperatures through mid week.
450 PM MDT Mon Aug 5 2019 Highly anomalous ridging over Alaska has allowed lower heights to drop into the central Canadian Provinces. though stronger height falls to the North will keep the ridge suppressed instead of amplifying it back into the Canadian Rockies as has been the pattern lately. Temperatures not quite as cool tonight but with dewpoints going downward will trend toward or just below the lower guidance numbers.
High pressure across the Straits and south Florida will maintain southwest to west winds around 10 knots with seas of 2 feet or less over the Gulf waters the remainder of the night and into Tuesday.
505 PM MDT Mon Aug 5 2019 Strong upper high/ridge continues across the Desert SW. Daily thunderstorms will continue through the week as the upper ridge persists across the region, pushing slightly farther eastward toward the end of the week into the weekend.
650 PM CDT Mon Aug 5 2019 With the exception of a few showers across southern Missouri that may linger into this evening, tonight and overnight will be mild as a cold front makes its way across the northern plains.
318 PM MDT Mon Aug 5 2019 A weak short wave trough will move through the area late tonight and may trigger an isolated shower or two south of the Missouri River. A cold front will move through the region tomorrow afternoon and may trigger an afternoon storm or two somewhere in the Sidney to Glendive area where moisture is the most abundant.
Then a long break in the precip chances are expected, with afternoon storm development along the cold front, mainly after 2 pm. Dry weather is then expected Fri through Sun evening as dry, slight cooler, high pressure builds into the region.
TFJ A weak short wave trough will move through the area late tonight and may trigger an isolated shower or two south of the Missouri River. A cold front will move through the region tomorrow afternoon and may trigger an afternoon storm or two somewhere in the Sidney to Glendive area where moisture is the most abundant.
630 PM CDT Mon Aug 5 2019 High pressure is quickly winning out this afternoon, with the cold front now south of the forecast area. The next cold front will stretch from the ND/SD border to northeastern North Dakota at 21Z Tuesday will be shifting into central SD by early evening. This sets the stage for high dew points in the low to mid 60s, and temperatures rising to near 90 degrees, along with MLCAPE values over 2500J/kg, deep layer shear of 35 to 50 kts, and a low level jet of 30-35kts developing later in the evening.
High pressure is quickly winning out this afternoon, with the cold front now south of the forecast area. The next cold front will stretch from the ND/SD border to northeastern North Dakota at 21Z Tuesday will be shifting into central SD by early evening. This sets the stage for high dew points in the low to mid 60s, and temperatures rising to near 90 degrees, along with MLCAPE values over 2500J/kg, deep layer shear of 35 to 50 kts, and a low level jet of 30-35kts developing later in the evening.
Also Cu field diminishing quickly over the last hour with high pressure bringing dewpoints down into the mid 50s for much of the area. Some cirrus will increase from the northwest late tonight and Tuesday morning with some mid level CU/AC developing Tues aftn ahead of the next cold front.
351 PM MDT Mon Aug 5 2019 Ridge over Arizona will move eastward tonight through Tuesday allowing moisture to move into southern Utah.
Lows tonight will drop into the upper 60s, with highs on Tuesday in the lower to middle 80s. Weak low level theta-e advection and boundary layer destabilization on the backside of high pressure may allow for isolated showers (20% PoP) to pop up near a Lake MI shadow late this afternoon into early this evening. Renewed vigorous re-development will then be likely along this composite outflow and/or primary cold front Tuesday afternoon, though latest guidance continues to differ on where this takes place. Cloud cover should result in a slightly cooler day otherwise, though remaining seasonably humid with dewpoints in the mid-upper 60s.
With the upper level trough currently located to the west, moist southwest flow remains in place overnight tonight. Temperatures drop into the low to mid 70s overnight tonight under partly cloudy skies.
Ridge axis continues well south of ECFL. A rather wet WX pattern to continue through midweek as a deep lyr troffing pattern over the SE CONUS keeps the Bermuda Ridge axis pinned over the FL Straits. High pressure ridge axis remains suppressed southward with initial SWRLY flow backing S/SERLY in the afternoon near the coast.
It is still fairly unclear what the longevity of thunderstorm activity will be this evening, as the low level flow will be fairly weak. Western Kansas will remain in a northwest flow pattern aloft on Tuesday, but the low level convergence field will redevelop much farther west/northwest into Colorado, so any convective activity should remain well to the northwest of the DDC CWA.
/issued 316 PM CDT Mon Aug 5 2019/ Strong upper level ridge over the southern Rockies/Southwestern US will shift east over the Southern Plains during the week. This will limit convection/precipitation chances across all but the northwestern one-quarter to one-third of the forecast area where weaknesses in the upper-level ridge rotate clockwise across the higher terrain of New Mexico and west Texas.
This will continue to keep afternoon highs under the 90 degree mark this today despite continued warm advection trends ahead of an upstream cold front. As the Four Corners ridge continues to build through the late week and into the weekend time frame, embedded disturbances overhead the local area will maintain the active pattern through the next several days.
750 PM EDT Mon Aug 5 2019 High pressure will slide east tonight allowing more humid and unsettled weather to enter the region.
738 PM CDT Mon Aug 5 2019 For the 06/00Z TAF period, VFR conditions should prevail this pd as upper level high pressure ridge continues to largely dominate.
An Atlantic ridge axis will be located across the Keys on Tuesday. An Atlantic ridge axis will meander near the Keys through Tuesday, then move north to across extreme South Florida on Tuesday night.
We'll then see one more day of warmer weather, before we start transitioning to at or below normal highs due to an approaching trough. CAPE, LI's, total totals, and PWATS support at least some cumulus build up each day on the higher points of the terrain.
/issued 738 PM CDT Mon Aug 5 2019/ For the 06/00Z TAF period, VFR conditions should prevail this pd as upper level high pressure ridge continues to largely dominate.
1145 PM CDT Mon Aug 5 2019 /06Z TAFs/ Tranquil flying conditions are expected over the next 24-30 hours, beneath the influence of a building upper ridge. A typical summertime synoptic pattern continues across North America with a stout upper-level ridge over the Southwest. The upper-level ridge will strengthen over the next few days, with the axis of this ridge moving to the east.
I have bumped PoPs into the low-end likely category to account for this possibility, but with the northwest flow aloft, there is always the potential for portions of the line to break up as it traverses Middle TN, ending up with some not even seeing rain.
1158 PM CDT Mon Aug 5 2019 For the 06/06Z TAF period, VFR conditions should prevail for most of this pd as upper level high pressure ridge continues to largely dominate.
1023 PM MDT Mon Aug 5 2019 Strong upper high/ridge continues across the Desert SW. Daily thunderstorms will continue through the week as the upper ridge persists across the region, pushing slightly farther eastward toward the end of the week into the weekend.
The region of higher moisture over the coastal plains is expected to diminish slightly today as the mid level ridge slowly builds into the area.
1039 PM PDT Mon Aug 5 2019 High pressure returns with warming temperatures through mid week.
Some areas may see temperatures drop even cooler depending on local effects. Secondly, high temperatures were nudged up tomorrow as an 850mb thermal ridge develops in the prefrontal regime. Depending on how convection and thus cloud cover develops tomorrow, less shielded areas may see temperatures reach the low 90s. This will bring a surface cold front through the region by evening. Highs Tuesday will be around 90 southwest to the lower 80s northwest.
322 AM CDT Tue Aug 6 2019 In the wake of the cold front, temperatures will only be slightly cooler today, with highs in the low/mid 80s.
336 AM CDT Tue Aug 6 2019 Sruface high pressure over the region this morning responsible for clear and calm conditions will move south. This is ahead of an approaching cold front from the north that should be responsible for helping storms initiate across the region. CAPE values between 1-2 kJ/kg will be common within buoyant the air mass ahead of the cold front. However as storms develop and move east off southwest-northeast oriented cold front, storm to storm interaction may cause clustering and hinder updraft sustenance. As the cold front moves through from the north this evening, winds shift out of the north with dipping temperatures into the 50s for the overnight.
110 AM CDT Tue Aug 6 2019 Forecast still on track as high pressure largely dictacts the overnight weather. Also Cu field diminishing quickly over the last hour with high pressure bringing dewpoints down into the mid 50s for much of the area. Some cirrus will increase from the northwest late tonight and Tuesday morning with some mid level CU/AC developing Tues aftn ahead of the next cold front.
233 AM CDT Tue Aug 6 2019 (Today and Tonight) Another round of scorching heat is in store today as a 592 Dekameter ridge starts building back into West Texas. The only discrepancy is a slight weakness on the eastern periphery of the ridge which, combined with some higher moisture, may help a few afternoon thunderstorms to develop over the Hill Country.
High pressure moving into Iowa will bring light north winds. Northwest flow aloft will dominate with an upper low to our north. Light west winds will prevail with the high moving into Illinois.
1202 AM CDT Tue Aug 6 2019 With the exception of a few showers across southern Missouri that may linger into this evening, tonight and overnight will be mild as a cold front makes its way across the northern plains.
High temperatures will be in the low to mid 90s and lows tonight in the 60s.
This change should allow the Atlantic sea breeze to advance slightly further inland today compared to previous days but not enough to remove the high threat of rain from along the east coast metro. Aloft, the mid to upper level longwave trough sits over the eastern Gulf of Mexico and over a good portion of the peninsula of Florida. Slightly cooler air (-7 deg C or so at 500 mb) aloft today could allow for increased lightning activity today.
Today through Tonight An upper level high is currently centered over New Mexico. This high pressure system is progged to move east over the next couple of days.
404 AM EDT Tue Aug 6 2019 A strong trough sitting over the east coast of Florida is showing no signs of moving through the rest of the week.
South to southeast winds will increase across western and north central Nebraska on the backside of the high. The NAM has the highest CAPE (4000+ J/KG) in a north to south corridor from Valentine to North Platte to McCook or roughly along Highway 83. Atop this high CAPE environment will be deep layer shear on the order of 45 to 50 kts. The most likely scenario to evolve from this would be a couple of intense southeastward moving supercells through the high CAPE environment across the Sandhills and adjacent north central through southwest Nebraska.
The forecast is about the position of the upper high and the extent of influence over the region. The upper ridge over the western U. Models show the center of the upper high gradually shifting into the southern Plains later this week.
In the upper levels a trough remains over the Southeast. Highs today will be near 90 or in the lower 90s.
250 AM MDT Tue Aug 6 2019 Current surface analysis shows one frontal boundary south and west of the forecast area, with a cold front across south central Canada. In between, weak high pressure is in place across the Dakotas. Upper level analysis shows high pressure centered over eastern AZ, with ridge extending northward through the eastern Great Basin and into the Pacific NW. Somewhat quieter conditions are expected across the area over the next couple of days as the ridge remains relatively far west of the region and less active/drier northwest flow persists. Today will be the warmest day of the week, ahead of the cold front to the north that will slide through the northern Plains later today and tonight.
A stronger upper level trough looks to dip across northern parts of the region on Wed - consistent signal in the models. The bulk of the upper level forcing hold north, but an associated sfc cold front leads the trough across the region. Deeper shear hangs back into the cooler air, but some overlap of more favorable 0-3 km for the aft/eve around 30 kts. As it sits, the higher chances for showers and storms locally look to lie in the I-94 corridor and north-east. Weak high pressure fills in behind the departing Wed system, resulting in a cooler, less humid and dry end to the work week. The GFS and EC then suggest an upper level ridge over the Rockies will work east to across the plains for the weekend.
1134 PM MDT Mon Aug 5 2019 Highly anomalous ridging over Alaska has allowed lower heights to drop into the central Canadian Provinces. though stronger height falls to the North will keep the ridge suppressed instead of amplifying it back into the Canadian Rockies as has been the pattern lately. Temperatures not quite as cool tonight but with dewpoints going downward will trend toward or just below the lower guidance numbers.
Nwly flow prevails aloft across the TN Valley and Southern Appalachian region this morning as a trough axis slides east atop the Mid-Atlantic coastline and a deep/broad H5 anticyclone dominates westward. At the surface, an old stationary boundary remains laid across portions of SC/GA/AL, while weak high pressure builds across the TN Valley.
SHORT TERM (Now through Wednesday): The Rio Grande Valley and Deep South Texas will remain on the southeast edge of a sturdy 500mb ridge, centered over the Desert Southwest. Global models are in agreement that this ridge will shift eastward through the short term, with the center drifting over west TX/southeast NM by Wednesday afternoon. As the ridge shifts eastward, it'll broaden and become elongated in an east-west direction, trending the mid-levels of the atmosphere warmer and drier. With ridging building in, Wednesday looks drier and less likely for precipitation to occur.
Current surface analysis also shows a cold front draped over northern Michigan down through central Wisconsin, Iowa, and into southeastern Nebraska. Temperatures this morning range from the lower 60s in the far eastern valleys to around mid 60s on ridgetops. Dry conditions will persist through this morning, but a cold front will approach the northwestern portion of the state later this afternoon. Activity will then decrease substantially by early Wednesday evening as the cold front exits the state. High temperatures will reach the upper 80s today; however, highs will be slightly cooler tomorrow, in the low to mid 80s, due to the change in air mass. Clouds will increase tomorrow as a cold front approaches the state.
Slightly less activity is expected Wed with the upper ridge axis over the Four Corners starting to build east.
A trough remains across the Southeast today, with the axis of synoptic forcing for ascent shifting east of the Tri-State region. Dry air aloft associated with the trough will overspread the region through the day.
It still looks like the southwest mountains will see some thunderstorm development as the drier air will not intrude into the higher terrain.
Winds will remain light in the presence of weak ridging, becoming variable this afternoon with typical daytime heating of our neighboring land masses.
524 AM MDT Tue Aug 6 2019 Cold front will be dropping south from Canada today, with winds shifting to the north. Cooler air will be moving into the region but will be slow to work down to the surface. Cooler temperatures finally reach northeast Montana by Wednesday as Canadian high pushes into the northern Plains.
851 AM MDT Tue Aug 6 2019 Wyoming remains on the fringe of the ridge centered on the four corners region.
A strong cold front will move in from the west during the middle of the week. Cooler and drier air is expected for the end of the week. A weak boundary lying across the Mason Dixon will move back northward as trough deepens into the Ohio Valley. A deeper negatively trough will move into the region Wednesday. The cold front out ahead of the trough will move through Wednesday bringing an increased chance for showers and thunderstorms.
357 AM MDT Tue Aug 6 2019 Wyoming remains on the fringe of the ridge centered on the four corners region.
Temperatures are generally in the lower 70s with light winds and mostly clear skies. Latest GOES east water vapor imagery shows a large ridge over the Four Corners and Intermountain West with a trough over the eastern half of the United States. Mainly dry conditions are expected today as weak high pressure remains in place over the Lower Mississippi Valley. Expect highs in the lower 90s areawide. Expect highs in the low to mid 90s across much of the area.
Ridge axis draped over the nrn Bahamas/FL Keys will maintain a steady southerly flow acrs the lcl Atlc.
843 AM EDT Tue Aug 6 2019 Upper level trough axis was moving through the area this morning, with drier air aloft moving in from the northwest. Highs today will be in the lower 90s across the area, with heat indices around 100 degrees.
Overall we have more forecast models favoring our eastern zones and thus our forecast will also give the highest rain chances to our northeastern areas. Often this time of year we can see a giant upper ridge set up over us leading to hot and dry conditions. The upper high will be located well south over Texas through the period, which is where the truly hot weather should remain. The wind will be light and variable early this morning as a surface area of high pressure slides east across Nebraska. The wind will remain light throughout the day, but will become more southerly after the high passes to the east this afternoon.
/Today through Wednesday/ Upper lvl ridge centered near four corners region of sw conus expected to move little thru today. This will result in a day very similar to yesterday, characterized by isolated aftn convection across most of area, slightly more concentrated north and east portions of cwa where nw flow aloft is stronger around periphery of ridge, and temperature and dewpoint profiles that bring heat indices between 100 and 105 as dewpoints in upper 70s overnight only mix out to middle 70s in the daytime, with aftn highs in lower to middle 90s. A slight eastward shift of the upper ridge on Wednesday may provide that temperature uptick to middle and upper 90s that will begin pushing heat indices above 105 degrees, while convection, albeit still possible, appearing even more isold.
and Wednesday The main focus of the short term forecast will be the next possible round of severe weather, arriving along a cold front Wednesday afternoon and evening.
/issued 404 AM EDT Tue Aug 6 2019/ A strong trough sitting over the east coast of Florida is showing no signs of moving through the rest of the week.
Overall we have more forecast models favoring our eastern zones and thus our forecast will also give the highest rain chances to our northeastern areas. Often this time of year we can see a giant upper ridge set up over us leading to hot and dry conditions. The upper high will be located well south over Texas through the period, which is where the truly hot weather should remain.
An upper ridge will bring warm and dry weather to Western Washington through Wednesday. The high will weaken and move east as a low pressure system over the Eastern Pacific gradually moves onshore late this week.
424 AM CDT Tue Aug 6 2019 Eastern Oklahoma and Northwest Arkansas continued to be positioned on the eastern periphery of a ridge of high pressure over the Desert Southwest this morning. a slight chance of diurnal showers and thunderstorms will again be possible mainly within the higher terrain locations of Southeast Oklahoma and Northwest Arkansas. A slight chance will remain Wednesday afternoon over the higher terrain locations of Northwest Arkansas for any diurnal convection that may develop.
For 12Z Aviation discussion below In the wake of the cold front, temperatures will only be slightly cooler today, with highs in the low/mid 80s.
High pressure moving into Iowa will bring light north winds. Northwest flow aloft will dominate with an upper low to our north. Light west winds will prevail with the high moving into Illinois. This will be accompanied by a surface cold front that will be located in NW Wisconsin in the afternoon, reaching southern WI late in the evening. Expect another warm and humid day, then turning cooler, drier in the wake of the front.
Given recent dryness and resulting temperature biases, will again play the high end of max temp guidance with quite a few spots topping 90 degrees again.
625 AM CDT Tue Aug 6 2019 Scattered showers and thunderstorms are expected again from midday into early evening, as a cold front pushes across central Illinois. 08z/3am surface analysis shows a cold front extending from the Upper Peninsula of Michigan southwestward to near Kansas City. High pressure building into the Midwest behind the departing front will provide mostly sunny and dry weather on Wednesday with seasonal temperatures in the middle 80s.
/Issued 424 AM CDT Tue Aug 6 2019/ Eastern Oklahoma and Northwest Arkansas continued to be positioned on the eastern periphery of a ridge of high pressure over the Desert Southwest this morning. a slight chance of diurnal showers and thunderstorms will again be possible mainly within the higher terrain locations of Southeast Oklahoma and Northwest Arkansas. A slight chance will remain Wednesday afternoon over the higher terrain locations of Northwest Arkansas for any diurnal convection that may develop.