Aikyam-Lab/Synoptic-Bench huggingface dataset:
322 AM MST Sat Jan 21 2017 An upper trough stretching from the Pacific Northwest southeast into Arizona and Mexico will be transitioning across the area today. The subsidence on the backside of the trough and strong northwesterly flow aloft will increase surface winds over the mountains tonight, gusts up to 45 mph will be possible. High pressure ridge aloft will transition across Colorado on Sunday with drying conditions over the mountains and lingering gusty winds over the mountains and east slopes.
The dense fog has recently shown some expansion into parts of north central Wisconsin while the higher terrain of the remainder of western Wisconsin was also likely experiencing dense fog.
In the upper levels, southwest flow will push the stalled surface boundary along the coast back to the north as a warm front this afternoon. Any lingering precipitation should move out of Arkansas during the evening Sunday, as the upper low moves into the Ohio Valley. This would be on the back edge of the upper low, with any stronger storms that develop.
Highs will reach the low to mid 80s across much of the region. The low-level jet is forecast to strengthen, and 0-1km helicity values are forecast to increase to >400 m2/s2 across portions of southeast Georgia and the Suwannee Valley overnight tonight.
/Issued 635 AM EST Sat Jan 21 2017/ Short wave lifting out of the lower Mississippi Valley will be the main driving force today. 20 Models in better agreement at the start of the period with the closed upper low vicinity of the TN valley.
Given clearing skies over northern Indiana and northwest Ohio, and given very warm low level thermal fields as reflected by the latest aircraft soundings, have raised highs into the low to mid 60s today. Surface warm front currently draped over southern MI with just enough gradient flow and warm air at the surface to yield visibilities at or above 5 miles to the south. North of the toll road, visibilities were more variable earlier this morning but have since improved with warm front surging north. 925mb temps climb solidly into the lower teens by this afternoon with surface temps already in low 50s across much of the area. Remained on the pessimistic side with cloud forecast but did trend toward a much less cloudy/warmer forecast, especially in our SE.
511 AM MST Sat Jan 21 2017 CWA currently between systems with an upper low drifting north over North Dakota and a negatively-tilted upper trough moving over the southwestern CONUS. Narrow area of clear skies currently over the CWA but mid/high clouds starting to increase from the southwest in association with the southwestern upper trough. Mainly dry conditions return for a time later tonight through Sunday as an upper ridge amplifies and moves across the Rocky mtns. Snow showers will then increase over the far western parts of the CWA Sunday night as the upper ridge axis moves east over the plains and increasingly moist southwesterly flow sets up.
a strong upper level trough was poised to move into Texas and Oklahoma this evening resulting in moisture and instability returning to our area late this afternoon into tonight. Showers and thunderstorms are expected to develop this evening along and ahead of the cold front tonight. Northwest winds are expected to be brisk on the back side of the low.
Main forecast issues in the short term come with a deep upper level low that will form and move east out of the southern Plains later tonight and Sunday. Model consensus seems to be converging on a solution which take this low from the near the Red River Valley of TX/OK east- northeast into the TN River Valley by Sunday afternoon.
305 AM MST Sat Jan 21 2017 CWA currently between systems with an upper low drifting north over North Dakota and a negatively-tilted upper trough moving over the southwestern CONUS. Narrow area of clear skies currently over the CWA but mid/high clouds starting to increase from the southwest in association with the southwestern upper trough. Mainly dry conditions return for a time later tonight through Sunday as an upper ridge amplifies and moves across the Rocky mtns. Snow showers will then increase over the far western parts of the CWA Sunday night as the upper ridge axis moves east over the plains and increasingly moist southwesterly flow sets up.
538 AM CST Sat Jan 21 2017 Manual 00z upper-air analysis and early-morning water vapor imagery indicate the presence of a high-amplitude wave pattern over the lower 48 states. In the low levels, a moist air mass which has contributed to areas of dense fog and drizzle/rain showers early this morning will become displaced by a drier boundary-layer advecting into the the mid MO Valley from the west and northwest.
403 AM CST Sat Jan 21 2017 Several weak upper lows meandering through the Northern Plains over the next 24 hours will result in little to no ventilation through the atmospheric column. This allows shallow cool air to create favorable conditions for fog and the lack of seeder/feeder ice crystals will support drizzle/freezing drizzle. patchy freezing drizzle will be common across the much of the central and eastern sections. Expect little change in temperature today and tonight beneath the low clouds and fog. Sunday will see a slow end to the thermal profiles supporting the fog and drizzle/freezing drizzle as the flow aloft becomes more westerly with the upper lows exit.
High pressure, marred only by residual morning and increasing high cloudiness, will maintain dry and warm conditions today. In addition to the moisture, waves of energy, revolving around the upper low, will also move northward Sunday afternoon. At the surface, low pressure will rapidly develop beneath the upper low tonight and move quickly eastward on Sunday with the strong upper level support.
635 AM EST Sat Jan 21 2017 Short wave lifting out of the lower Mississippi Valley will be the main driving force today. 20 Models in better agreement at the start of the period with the closed upper low vicinity of the TN valley.
Scattered showers will linger in the lower elevations through today with snow showers continuing over the mountains.
An upper trough stretching from the Pacific Northwest southeast into Arizona and Mexico will be transitioning across the area today. The subsidence on the backside of the trough and strong northwesterly flow aloft will increase surface winds over the mountains tonight, gusts up to 45 mph will be possible. High pressure ridge aloft will transition across Colorado on Sunday with drying conditions over the mountains and lingering gusty winds over the mountains and east slopes.
645 AM CST Sat Jan 21 2017 Made a few minor tweaks to temperatures and therefore the drizzle/freezing drizzle designation. Fog, drizzle, and freezing drizzle continue to be the main challenges for the short term. An upper low with several circulations has been lifting northward across the Northern Plains and Upper Mississippi River Valley. Model soundings have dry air aloft for much of the day so will keep precip mention drizzle or freezing drizzle with little QPF. There remains some very light QPF put out by most of the models but with dry layer aloft remaining over most of the area think that it will still be mostly drizzle or freezing drizzle.
and low pressure over the upper Midwest. Mid and high clouds associated with the southern system will drift across the region for much of the day with additional clouds arriving towards sunset as low pressure organizes over the Texas panhandle. Bumped up highs a degree or two as most areas should rise into the lower and mid 60s.
Made a few minor tweaks to temperatures and therefore the drizzle/freezing drizzle designation. Fog, drizzle, and freezing drizzle continue to be the main challenges for the short term. An upper low with several circulations has been lifting northward across the Northern Plains and Upper Mississippi River Valley. Model soundings have dry air aloft for much of the day so will keep precip mention drizzle or freezing drizzle with little QPF. There remains some very light QPF put out by most of the models but with dry layer aloft remaining over most of the area think that it will still be mostly drizzle or freezing drizzle.
636 AM EST Sat Jan 21 2017 An upper-level trough will left northeast into the region, bringing a broad area of -TSRA/SHRA into the region late this morning into the afternoon.
Chattanooga Airport, TN 66 55 63 47 / 80 80 90 90 Knoxville McGhee Tyson Airport, TN 65 53 65 49 / 70 70 80 90 Oak Ridge, TN 65 53 64 49 / 60 70 80 90 Tri Cities Airport, TN 64 50 65 48 / 60 50 80 100.
/Issued 336 AM CST Sat Jan 21 2017/ Compact but potent upper low at the nose of strong Pacific jet was moving across the desert SW this morning, and will be the primary weather feature in this forecast cycle. Upper level flow will amplify in wake of this system for the latter half of the week with ridge axis along the west coast and deepening eastern trough.
Some light to moderate precipitation will continue this morning as an upper level trough and associated weak front slide north through our area.
914 AM EST Sat Jan 21 2017 High pressure will move east of the area today. A weak cold front will cross the region tonight.
Ridging aloft will keep the area dry today. However,plenty of moisture will be trapped below the ridge, so clouds will hang around. In addition to the moisture, waves of energy, revolving around the upper low, will also move northward Sunday afternoon. At the surface, low pressure will rapidly develop beneath the upper low tonight and move quickly eastward on Sunday with the strong upper level support.
Increasing S/SW flow will produce a warm day with near record high temperatures possible in the low to mid 80s. Breezy/windy southwest flow will allow temps to soar into the low to mid 80s in the afternoon. The S/SW pressure gradient will tighten as high pressure pushes east and away from the area.
1140 AM CDT SAT AUG 20 2016 The primary cold front continues to slowly migrate through the area late this morning, roughly from Freeport to Macomb at 11 am. Upper level trough digging into the plains this morning with a lead wave now lifting out over the upper Mississippi valley and the main energy with the trough over south central South Dakota. Cold front and associated storms are tracking most closely to the timing of recent runs of the ECMWF, thus will use this as a general basis for this morning's forecast.
Behind the front cooler and more stable air is advecting in on breezy northerly winds. /issued 409 AM CDT SAT AUG 20 2016/ A pre-frontal trough was working its way out of the Rolling Plains as of this writing. As of 3 AM, the cold front was rapidly pushing southward into the central TX Panhandle. The cold front should be through most of the South Plains by daybreak, bringing one last shot at precipitation. To our west, a ridge will be present from NW Mexico up the spine of the Rockies.
659 AM CDT SAT AUG 20 2016 Upper trough axis is moving eastward across the eastern Dakotas early this morning. Showers continue to move across the CWA with the highest concentration over the eastern CWA. The upper trough will move into MN later this afternoon, with weak instability residing across eastern SD and west central MN. This is a cool high pressure system, and if ideal radiational conditions set up, we'll be looking at some rather chilly morning lows come Sunday morning.
Models are continuing the trend of speeding up the cold front through the area, and the majority of models have no precip over the mid state by late afternoon on Sunday. Would not be surprised if models keep speeding up the cold front as well as the upper trough, and having most of the mid state seeing partly cloudy skies by Sunday afternoon.
High pressure will move into the forecast area today, resulting in a drying trend for much of the area.
617 AM CDT SAT AUG 20 2016 06Z TAF Cycle Lingering showers behind a cold front will continue this morning at all three TAF sites through 16Z or so today. /Issued 421 AM CDT SAT AUG 20 2016/ Showers and thunderstorms have continued moving across the Panhandles overnight in connection with the front and the upper level trough. As the trough moves east and the front pushes further south into Texas, the precip will move away also. A push of dry air in the mid levels will keep the area dry for Sunday as ridging begins to build in.
Upper level analysis places low over southwestern Hudson Bay with trough stretching from the northern Red River Valley to the south-southwest into central Nebraska. Broad area of showers continue ahead of the trough, while a few showers are starting to re-develop to its west as the next short wave slides down. A few showers will continue today as a variety of weak waves drop down on the backside of the trough. Swift warming trend will start the week as upper ridge builds back into the area, with highs pushing back into the 90s over many locations.
Northwest flow aloft will back to westerly by Sunday afternoon as a trough takes aim at the Pacific NW. In advance of this trough we will see warm air advection add close to 5 degrees to the high temperatures from today to tomorrow. However, late Sunday afternoon westerly winds will be over 10 mph in southeast Oregon as the trough approaches.
Secondary cold front currently moving through the area has some isolated shower activity which may linger a few more hours. Drier and cooler air will continue to filter into the area today with highs in the mid to upper 70s. High pressure will build into the region behind the front and track over central KS tonight. Low temperatures will dip into the mid to lower 50s tonight as the high pressure tracks through the area. Tomorrow return flow will cause slightly warmer highs in the lower to mid 80s. Sunday remains on the cool side with highs in the lower 80s as upper trof continues to move into the northeast and becomes more zonal over the Central Plains through the day.
Attention will focus to an upper level trough and marine push on Sunday which may create fire weather concerns. Fire weather concerns this weekend will be the dry and marginally unstable air mass bringing the Haines to a 5 (moderate category) and the low relative humidity in addition to the increasing wind on Sunday. Fire Weather Watches are in effect Sunday for the zones covering the Eastern Columbia River Gorge and the Simcoe Highlands and the Lower Columbia Basin south of the Tri- Cities.
/Issued 320 AM CDT SAT AUG 20 2016/ Scattered showers/thunderstorms will continue this morning ahead of cold front which will move into northeast Oklahoma later this morning.
The forecast area is currently situated along the southern edge of westerlies with a broad upper-level trough over the Plains. As the larger trough shifts into the Ohio Valley on Sunday, an area of enhanced convective activity will be focused along a weak front that will traverse the CWA from the North in the morning to the central and southern parts of the area during the afternoon and evening.
A deep layer ridge remains in place with a weak surface pressure pattern. Convection will gradually dissipate again this evening as the low levels stabilize. Negligible vertical shear and elevated WBZ heights will put the threat of severe weather on the low end of the risk spectrum. Maximum temperatures near 90 along the coast climbing into the low to mid 90s in the interior are anticipated. Overnight lows will generally range from the low to mid 70s to near 80 along the coast.
/issued 409 AM CDT SAT AUG 20 2016/ A pre-frontal trough was working its way out of the Rolling Plains as of this writing. As of 3 AM, the cold front was rapidly pushing southward into the central TX Panhandle. The cold front should be through most of the South Plains by daybreak, bringing one last shot at precipitation. To our west, a ridge will be present from NW Mexico up the spine of the Rockies.
Temperatures ranged from the low to mid 50's across the north to the lower 60s across much of the south. Low pressure is expected to strengthen as it lifts into Upper Michigan by this evening, although not nearly as much as the NAM had been advertising for several runs. Winds will strengthen from the north as the central pressure of the low drops into the 990 MB range. The rain and clouds will gradually end from west to east and south to north tonight, allowing high pressure to build into the Northland. Initially in the extended, high pressure will build into the central Great Lakes. Minnesota will be on the western side of the high along the return flow of southwesterly winds and strong WAA.
A cold front will move into northern Oklahoma bringing slightly drier air as well as increasing north surface winds. Model guidance highs appeared reasonable and were accepted, mainly in the lower to mid 80s. Sunday will be mostly sunny with low humidity and cooler than average temperatures in most locations. Sunday night, the front in Texas will slowly lift northwards as a warm front.
Looking upstream to the northwest there are some high clouds riding across the top of the western ridge that may drift into our area later today. Templer Previous Discussion - After a cool morning across northeast Montana with temperatures in the 40s to low 50s, expect afternoon highs to recover well into the 70s with an abundance of sunshine thanks to a building upper level ridge of high pressure.
Overall it appears that rather wet and stormy conditions will prevail through the day and into tonight ahead of a cold front. The cold front should sweep across the region late tonight into Sunday.
1030 AM EDT SAT AUG 20 2016 Scattered showers with isolated thunderstorms have been diminishing in areal coverage and intensity south of the Lower Keys and Dry Tortugas this morning.
Additionally a secondary cold front with more of a northerly wind is moving south across the FA this morning.
West Atlantic ridge axis will persist across south Florida today with a general W/SW low level flow over much of the region. (previous discussion) The weak Atlantic ridge axis will continue to slip south across Lake Okeechobee/Treasure coast resulting in a light south/southwest flow of 10 knots or less.
1004 AM EDT SAT AUG 20 2016 A strong cold front will move through the forecast area early Sunday morning. High pressure will build over the region for the start of the week. Warm air advection will occur today in advance of an approaching cold front. Dew points in the lower 70s will creep northward into the county warning area.
Ongoing convection across sections of Wisconsin will also help to deepen the low this morning. However, until the low starts lifting to the northeast, cannot rule out some locally heavier rainfall at times. Will hold onto the Flash Flood Watch until the low passes and the heavier rain environment edges into eastern sections of Wisconsin. 8 range and can just see a warm frontal feature near the interstate 94 corridor across western into central Wisconsin this morning. Showers look to linger across northern Wisconsin this evening as the low lifts northeast over eastern Lake Superior.
This will go in tandem with high pressure working over the Plains to provide a nice dry day.
1225 PM EDT Sat Aug 20 2016 A cold front will bring better rain chances tonight into Sunday. Rain chances increase tonight as a pre-frontal mid-level trough moves up the Ohio Valley. Models indicate that convection along this trough axis will be decreasing as it enters our western counties late this evening. Still, with moisture and lift increasing ahead of the cold front, an gradual increase to likely PoPs was maintained. The cold front will arrive in the pre-dawn hours.
915 AM MDT SAT AUG 20 2016 Ridging continues to work into the area this morning. Bumped forecast highs to around 80 degrees today and then back into the lower 90s on Sunday. The only shot looks to be late Sunday afternoon and evening over the southwest mountains as the flow backs to the west, and a weak combines with some pacific moisture to develop some cu over the higher terrain. as models are beginning to bring a bit more moisture in to the area as upper level low slides across southern Canada.
Rounds of scattered rain showers and perhaps an isld t-storm will continue through early afternoon ahead of an approaching cold front. High temps still look to be in the lower 80s. Low pressure is developing over eastern Iowa, along a frontal boundary that is interacting with a trough diving across the Central Plains this hour. Latest ARW/NMM WRF's both show some scattered precip the rest of the morning hours, followed by another round later this afternoon and then a third closer to the cold front.
1130 AM CDT SAT AUG 20 2016 Widespread rain with a few embedded thunderstorms continues across far southeast OK well ahead of the cold front, which was located near to just south of I44 at 11 AM. /Issued 320 AM CDT SAT AUG 20 2016/ Scattered showers/thunderstorms will continue this morning ahead of cold front which will move into northeast Oklahoma later this morning.
High pressure over the Eastern Pacific and a ridge aloft will maintain mild conditions across the region.
Northern California remains between high pressure over the Pacific Northwest and a weak low pressure system over Southern California.
602 AM CDT SAT AUG 20 2016 Showers were moving across the region early this morning in advance of a cold front that was moving to the south across eastern Kansas. The cold front will make its way through the region this morning, pushing through the area by mid day. Cloud cover will quickly diminish in the wake of the front with cooler and drier air moving into the area for this afternoon and through tonight.
Otherwise, it will be much cooler than normal today with breezy northwest winds at 10 to 20 mph and highs only in the lower and mid 70s. High pressure begins to settle over the forecast area this evening, resulting in clearing skies and diminishing winds.
Deep layer ridge is located just south of the area resulting in prevailing flow from the west with JAX 12z sounding showing 0-8 km flow at 270 deg at 10 knots which is a few knots higher than yesterday. We also noted warmer temps in the low levels.
A low-level high pressure circulation will remain positioned over south central Arizona through Sunday. The circulation around the high will continue to push moisture residing over the Gulf of California/northwest Mexico into Arizona and across the Mogollon Rim. In addition, a weak trough aloft will provide a cooler than normal mid-level air mass and weak upward motion.
merging of eastern Pacific and Gulf moisture), several mid- level disturbances pushing off the Mexican mountains into the Rio Grande Plains and a cold front pushing as far south as the Hill Country later this evening is likely to promote localized heavy rain and flash flooding.
these showers and some thunderstorms are expected to increase in coverage as a broad upper-trough intensifies and tracks east toward the region. the main threat will be locally heavy rainfall and flooding from heavy downpours given the high PWAT values noted on model soundings. in the low to mid 80s. Chattanooga Airport, TN 86 72 85 65 / 70 60 60 10 Knoxville McGhee Tyson Airport, TN 85 70 84 62 / 70 60 50 10 Oak Ridge, TN 83 70 84 61 / 70 60 60 10 Tri Cities Airport, TN 82 69 82 58 / 60 60 60 20.
along a H850-700 theta-e axis that has developed ahead of a weak cold front extending from extreme NW AR into Ern OK/Ncntrl TX. widely sct convection may still develop over portions of the lower Toledo Bend Country into Ncntrl LA. until the upper trough bisecting the Plains into the lower TX Panhandle is able to slide SE and shift the diffuse shear axis/subtropical moisture plume aloft farther SE into the area atop the weak ridging aloft noted along the Gulf Coast/Gulf of MX. and raise temps a tad across the lower Toledo Bend Country into Ncntrl LA where the stratocu has lifted and better insolation is expected.
1032 AM EDT Sat Aug 20 2016 Weak high pressure will drift offshore today. A cold front will move through the area Sunday afternoon.