Aikyam-Lab/Synoptic-Bench huggingface dataset:
348 AM CST Fri Dec 15 2017 Upper trough axis well south into southern plains this morning, and with Hudson Bay low moving east there is ridging across the western CONUS placing the northern plains in fast northwest flow. Dense Cirrus topping the ridge and moving southeast across the Dakotas, should skirt western and north central Nebraska today.
Trough swinging through could bring ceilings down to flirt with the MVFR range, but will lift in morning.
1145 PM CST Thu Dec 14 2017 High pressure continues over Arkansas tonight.
117 AM EST Fri Dec 15 2017 VFR under high pressure. Forecast appears to be on track for this evening, with only minor updates made to show a bit cooler temperatures for the overnight with the latest guidance. High pressure moves offshore beginning tonight leading to a warming trend and a continuation of dry and benign conditions. Min temps much milder tonight and forecast to warm into the mid/upper 70s most areas Friday afternoon with slightly cooler afternoon temps along the Se Fl coast due to local seabreezes.
A stray shower is possible on the Plateau this afternoon, but the high pressure overhead is so strong that there may only be a few trees in the forest that get any relief from a shower. A high pressure area, both surface and aloft, will keep VFR conditions in place for most of the forecast period--except late at night and early in the morning, when patchy BR will produce a mix of MVFR and IFR conditions at CKV, MQY, and CSV.
Ridge at 500 mb was over KS and OK eastward into MO and AR. Weak cold front should continue to sag southward tonight, and some storms possible mainly along or north of that boundary. Lows tonight across much of the area should drop to the lower or mid 70s (but might stay in the mid or upper 70s southern quarter). North or northeast winds on Saturday should allow for some cooler air to filter in, with highs mostly 90 to 95. There is some question whether or not the cooler and drier air will work down across all of southeast NE, but for now will not extend the heat headline for Saturday.
A hot day is expected again across the region as the mid to upper level ridge of high pressure remains anchored from the Central Plains into the southeast CONUS. Nonetheless, a potent wave riding within the stronger westerlies across the Northern High Plains will flatten this ridge while also allowing the surface lee trough to deepen over eastern CO. The pattern turns slighlty more active late Saturday as the mid to upper level ridge shifts back into the Intermountain West.
It should be slightly cooler tomorrow. We will likely see isolated to scattered thunderstorms develop this afternoon with the highest coverage over North Mississippi. A broad ridge across the US will slowly transition to weak Northwest flow from the Northern Rockies across the Great Lakes.
628 AM CDT Fri Jul 21 2017 Early this morning the large upper level ridge of high pressure that has been providing hot temperatures to the central and Southern sections of the country was centered over Northeast Oklahoma, Northwest Arkansas and Southwest Missouri, and will continue to contribute to hot temperatures and afternoon heat index values from near 105-109 degrees across the Four State Region. With the upper ridge weakening and reforming through the upcoming weekend as a series of short wave troughs of low pressure affect the Northern periphery while a piece of the previous East Coast cut off low retrogrades across the Southeast States and across the Gulf Coast States. For Saturday the daytime temperatures will be cooler and the resulting heat indices will remain below 105 degrees, therefore the heat advisory will not be extended.
730 AM EDT Fri Jul 21 2017 The upper low vicinity of north FL should continue to drift southwest and weaken. The main feature is the upper ridge that will persist and nose eastward across the forecast area. The upper ridge weakens slightly on Saturday and the lee side trough looks more pronounced. Afternoon temperatures should range in the low to mid 90s for much of the forecast area today and mostly low to mid 90s Saturday.
High pressure east of the area will provide southeasterly winds today becoming southwesterly tonight.
Recent development over FSD CWA seems to be related to the low level jet. Much like a couple days ago, the main stories today will be the high heat and the threat for severe storms for eastern areas. That mid level flow pattern should feature a continuation of a southern/southwestern ridge, with various s/ws tracking across the Northern Plains/southern Canada.
A look at the morning sounding shows cooler temperatures aloft (around -10 degrees C at 500 mb) and relatively light low-level flow. It should also be noted that our chances for a few stronger (and possibly) severe storms will be a bit higher today due to the cooler temperatures aloft. High pressure will remain over the coastal waters through the next several days, with relatively light winds and seas.
500 mb heights have dropped some to 591 dm as well, indicating the upper ridge has weakened a bit and shifted north. Two upper lows to the east.
Movement has been extrapolated to the southeast, with a fading of the high POP with time. A slow moving cold front was dropping south through Indiana and Ohio early this morning. The cold front is expected to make it to near the Ohio River this evening, before stalling and heading to the northeast as a warm front tonight and Saturday. The highest probability of precip will be in our northern counties closest to the front, with some POP enhancement also in our southeast counties due to terrain. Based on the latest model data, the extended will be active and will feature periods of showers and storms and cooler weather. It appears that a frontal boundary will meander about the lower Ohio Valley and Upper Tennessee valley during the extended.
The new runs have slightly reduced PoPs through the day, as well as chances for thunderstorms, but still remain mostly in the high end chance category.
High pressure at the surface remains firmly entrenched across the forecast area. Rain chances will be less across the northern and western portions of the CWA, as these areas reside in closer proximity to the mid/upper level high. /19/ Prior discussion below: Today and Tonight: Mid/upper level high center will become situated over the Mid-South region this morning and continue to provide another hot day for much of the area. Some reprieve from the heat does look possible today as a mid level cold core low over FL slowly tries to move in underneath ridge axis. Over the north and west, better influence from the ridge will suppress most convection and give another hot and humid afternoon.
Saturday looks to be a carbon copy of today, except perhaps a bit more unsettled as the ridging starts to break down and retreat westward.
Despite the appearance of dry air on water vapor imagery to the west, nearly all of the lower deserts are swamped with pwats that are well into the 95th percentile.
/issued 326 AM CDT Fri Jul 21 2017/ (Today and Tonight) Dry and hot conditions in the short term, with the upper level high pressure still centered over the Mid Mississippi Valley.
As of 08z, SFC boundary extending from low pressure in eastern Montana extends across northern North Dakota. Also expect warmer mid-level temperatures to advect into the region this morning.
Smoke will also be an issue for some locations with active fires along the lower Musselshell river. High pressure builds into the region on Saturday. Humidity recovery may also be better with the slightly cooler airmass. Synoptic Setup: Long range begins with hot high pressure over the western half of the CONUS and centered over central Nevada. A ridge runs north out of this through eastern Wyoming, central Montana, and southern Alberta. A closed low has moves over British Columbia and begun to defuse. Farther west another low/trough is forming south of the Aleutians.
The first 12 hours of the GFS/NAM/ECMWF deterministic runs depict a very weak trough axis at 500-mb over the NERN CWA. The combination of the upper trough and near/above normal PWAT values (NAM deterministic) warrants 10-20% POPs over the ERN CWA/MSA Today. The deterministic output and the GFS ensemble mean depict the upper trough, currently affecting FL/NERN Gulf of Mexico, to affect the MSA/NERN CWA by Saturday afternoon.
South Central Texas continues to dry out beneath strong mid-level ridging and broader upper level ridging that spans much of the Southern US.
Expect VFR conditions to prevail across the Rio Grande valley and northern ranchlands today as the 500mb ridge across the south-central United States continues to provide subsidence across the area. /issued 358 AM CDT Fri Jul 21 2017/ SHORT TERM (Today through Saturday): 500mb ridge across the south- central United States and northeast Mexico will continue to provide subsidence across the Rio Grande valley and northern ranchlands today through Saturday.
A couple of small upper level troughs will brush Western Washington today through Saturday bringing clouds to all of the area and a chance of showers to the coast and north part.
Vapor imagery reveals a weak upper low moving across the marine area this morning and this will provide at least some assistance to developing thunderstorms this afternoon. Given that a little more convection is expected today, especially across the western half of the region, will show temperatures in the low to mid 90s in the western portion of the region, but in the mid 90s in the eastern half of the region.
In the meantime, expect temperatures to be rather warm today, with highs in the low to mid 90s, but max heat indices stay below 105 F in most locations.
In addition to the upper level wave, a surface cold front will drift through the area Saturday night.
08z surface analysis had low pressure over southeast MT with "cold" front into northwest WY and trough into central NE. Convective complex moving east along trough early this morning.
As low pressure tracks into Iowa, the front will get pulled northward this afternoon and will eventually stall along/just south of the I-80 corridor tonight. In fact, the southern tier of the country is dominated by an upper ridge and plenty of hot air that has moved into place aloft over the past few days. Until the upper ridge breaks down considerably, or a larger trof moves into the Upper Midwest later in the weekend, the trend will continue of hot, humid, and best chances for showers/TS confined to areas north of Interstate 74 from the outflow of the northern storms and the perimeter of that convection. The strength of the upper ridge is holding the bulk of the storms to the north. Said wave is starting to dig out a trof aloft and push through a slightly different airmass.
This low will act to increase thunderstorm coverage over the area today, with storms initiating along the coast and over eastern portions of the area this morning and gradually spreading westward and inland throughout the afternoon.
/issued 352 AM CDT Fri Jul 21 2017/ At least one more day of hot and dry weather will be in store for the area as the ridge remains in place one more day before starting to weaken.
A cold front approaching the US Highway 83 corridor around 18 UTC with a likely pre-frontal trough, with a weak stationary front across the US Highway 2 corridor will be the surface focal points for initiation. Deep layer shear of 30-40kts, locally higher, perpendicular to the cold front/pre- frontal trough favors discrete supercells in a highly unstable environment. However, initiation as early as 18-20 UTC is possible along the pre-frontal trough with the earlier impulses, with a later round of initiation possible with the stronger Canadian wave.
Continued with isolated to scattered showers through Midnight as outflows from the late afternoon storms will still interact with some warmer air as they slide north and south.
The high pressure area aloft over the plains states diminishes and the zonal flow turns more northwesterly over the forecast area with embedded short wave troughs expected to transition the forecast area each day as a series of low pressure centers moves along the U. /Canada border and high pressure amplifies over the western U. Relief from the heat will finally come this weekend following a cold front that moves slowly across the forecast area during the overnight hours tonight.
629 AM CDT Fri Jul 21 2017 Upper level ridge of high pressure will remain over the region today into Saturday.
The Pulley Ridge buoy in the southeastern gulf reported a wave height near 1 ft. Expect light to gentle breezes out of the south to southeast today as the ridge axis of the Bermuda High gradually shifts north to the Florida Peninsula.
653 AM CDT Fri Jul 21 2017 Upper ridge remains over region, so hot and humid conditions to persist today.
A strong upper ridge will remain in place, resulting in high temps mainly in the mid 90s. Lows tonight will be muggy, in the low to mid 70s.
1126 AM EDT Fri Jul 21 2017 Upper ridging will occur over the forecast area through Saturday.
Still, coverage of storms in SW VA and NE TN will probably be more than reflected in the current forecast, so the update will raise PoPs into the high end of the chance range for that area.
1015 AM EDT Fri Jul 21 2017 Central FL under an H100-H70 confluent zone with trough axis draped over the I-4 Corridor and the Atlc ridge axis blanketing south FL and the north Bahamas. KTBW/KMLB/KXMR wind profilers mapping the trough axis through the sfc-5KFT lyr with N/NW winds at KTBW veering to SW at KMLB/KXMR. Early morning convection in the Gulf Stream reflects the ascending right flank of the trough and points to another WX day for east central FL. Mid lvl temps have cooled a touch over the past 24hrs due to a lcl cool pocket asscd with a mid lvl cut-off low over the FL Big Bend. Atlc ridge axis over south FL/nrn Bahamas will combine with a weak trough over central/north FL to maintain a light to gentle S/SW breeze over the lcl Atlc.
/Issued 332 AM CDT Fri Jul 21 2017/ High pressure that has controlled the dry weather over the past few days will begin to break down as upper level flow will start to shift more out of the northwest.
Water Vapor satellite trends and 12Z upper air analysis this morning places an upper level ridge axis centered over the Lower Mississippi Valley. It should be slightly cooler tomorrow. We will likely see isolated to scattered thunderstorms develop this afternoon with the highest coverage over North Mississippi. A broad ridge across the US will slowly transition to weak Northwest flow from the Northern Rockies across the Great Lakes.
High pressure aloft dominating most of the central and southern Plains, with erosion from the east as the upper low over the eastern Gulf moves west. As the moisture and instability increases from the east with the approaching upper low, chances of showers and thunderstorms increase across Central and South Central Louisiana to the Atchafalaya river by late afternoon into the evening hours after maximum heating has occurred. With dewpoints in the lower to mid 70s, heat index values in the 100-107 range. In the meantime, expect temperatures to be rather warm today, with highs in the low to mid 90s, but max heat indices stay below 105 F in most locations.
/issued 313 AM CDT Fri Jul 21 2017/ The extreme heat and high humidity will persist through Saturday underneath the persistent and strong upper high pressure.
Strong high pressure and dry air remain over much of the northeastern quadrant of the US early this morning. with the pronounced upper level ridge axis aligned within this same area. Closest convection remains well upstream along and just behind a persistent inverted trough extending from Texas thru the Central Plains to near the Arrowhead of Minnesota. keeping general thunder west of our CWA along and ahead of the inverted trough. Pattern Forecast: Persistent upper level ridging across the eastern two thirds of the CONUS gradually begins to break down Monday night into Tuesday, which will allow for energy associated with western troughing to lift through the upper Mississippi Valley into Ontario.
A highly amplified flow pattern continues this morning across the CONUS with deep troughing over the western states and Rockies, and large scale upper ridging extending from the Great Lakes and New England south to the Southern Plains and Gulf of Mexico. A weak upper low continues to spin over the northern Gulf of Mexico this morning. At the surface, high pressure remains north of the region with persistent light east/northeast flow. Highs will be similar to yesterday in the lower 90s most areas, except near the coast where upper 80s can be expected. Highs may be a touch warmer as lesser cloud cover and drier air allow for more efficient heating, but lower to possibly mid 90s will generally be the rule across the region.
This is providing a east to east- southeast flow in the low levels that is allowing for elevated seasonal temperatures and moisture.
A large area of isentropic ascent over central KS has created a wide area of precipitation as warmer air aloft overrides the cooler air on the backside of the surface cold front located just west of Missouri now.
Gradual increase in clouds expected through the day across eastern OK as slow-moving cold front approaches from the west, with some showers or isolated thunder possible well after 00z. /Issued 401 AM CDT Mon Sep 25 2017/ Forecast trends remain consistent with warm temperatures and isolated showers today with a cold front moving slowly across much of the area by Tuesday evening. Extensive cloud cover and precip will keep temps noticeably cooler for northern locations on Tuesday with continued unseasonably warm temps south.
410 AM EDT Mon Sep 25 2017 A large area of high pressure remains parked just to our NE and will continue to stay in place through the short term portion of the forecast.
621 AM EDT Mon Sep 25 2017 An upper level ridge will remain over the region through mid week. Much cooler air will settle into the region by the end of the week. Another warm day is expected this afternoon with mid-level ridging slowly pulling east allowing 500 mb heights to slowly fall.
401 AM CDT Mon Sep 25 2017 Forecast trends remain consistent with warm temperatures and isolated showers today with a cold front moving slowly across much of the area by Tuesday evening. Extensive cloud cover and precip will keep temps noticeably cooler for northern locations on Tuesday with continued unseasonably warm temps south.
The weak system that is visible on satellite washes out to the north of our forecast area as the upper level ridge nudges over the top of our area. As the upper ridge continues to move over the region, offshore flow spreads across the east side by Tuesday morning.
618 AM EDT Mon Sep 25 2017 High pressure over the Eastern Great Lakes today will weaken and shift east Tuesday.
1141 PM MDT Sun Sep 24 2017 The overall pattern that has kept the Central High Plains region wet over the weekend will begin to shift eastward by late Monday as the upper low over the Great Basin begins to lift out across the Rockies and into the northern high plains. High temperatures on Monday should remain in the 50s while the overnight low temperatures will be in the lower 40s to middle 50s.
622 AM EDT Mon Sep 25 2017 High pressure continues its dominance through mid week.
There is a weakening cold front approaching the area, but it stays west of the MS river this afternoon. We still have a lot of ridging aloft and the soundings show the potential for enhanced low level drying due to mixing this afternoon. Look for another warm day today, though a few degrees cooler than yesterday, still in the hot category for late September. Medium One last day of abnormal warmth/dew points as approaching cold front likely to generate some shra/tsra.
Temperatures cold enough for snow in the higher elevations of the Black Hills. Could be a light dusting of snow in the higher Black Hills over the next few hours. The low lifts into western North Dakota by this evening.
300 AM CDT Mon Sep 25 2017 The upper-level ridge remains centered over the northeast CONUS early this morning with a longwave trough anchored over the west. Closer to our neck of the woods, a closed upper-level cyclone has drifted over the Mid-South, temporarily reducing 500mb geopotential heights (to ~584dam) and providing at least a small opportunity for precipitation. This upper-level low is forecast shear apart today with a portion lifting north around the western side of the anticyclone. With this low departing, mid-level heights will begin to rise and subsidence will increase.
342 AM MDT Mon Sep 25 2017 The longwave trough over the southwest U. Conditions will remain dry and cool at high pressure an rising heights and thicknesses will make little progress over the region. Clouds and showers will continue to rotate around the south side of the closed low over WY today, and these will affect the north-facing slopes of the eastern Uinta Mountains, and mid and hi cloud cover will continue to build back to the west over the Archuleta county area today. A Western Rex pattern looks to be well underway by mid-week with amplified ridging into the Pacific NW over-topping a closed low over the Desert Southwest.
318 AM MDT Mon Sep 25 2017 Overnight GOES-R water vapor loop showed the upper low spinning over western WY, with a trough axis extending to the Desert Southwest. Surface front from the western lake Superior through central IA/KS to a low pressure center over northeast NM has made slow eastward progress, with scattered elevated convection spreading north across the northern and central Great Plains.
402 AM CDT Mon Sep 25 2017 At the surface, high pressure over the St. The weak upper low near Gulfport will gradually sink southward into the northern Gulf of Mexico as it weakens. This will bring one more day of rain chances a little higher than climatology with most areas in the 40-50 percent range, before falling to 30-40 percent tomorrow as mid level ridging starts to build back in.
1224 AM CDT Mon Sep 25 2017 The large upper level trof that has been over the Rockies today, with its closed low over the Four Corners, will find the closed low opening up and lifting north before reforming in eastern Montana by Monday evening. Pieces of energy embedded in the lee side of the trof, will lift into the area tonight and Monday. Plenty of FGEN from the surface to 850mb right ahead of the upper trof.
Clouds increase today, especially across east-central Oregon and west-central Idaho in advance of an upper ridge. Skies clear from the west on Tuesday as the upper ridge continues to build into the region.
Aloft 500mb heights have dropped a few decameters with the weak upper low over the northern Gulf coast.
331 AM PDT Mon Sep 25 2017 Warmer through mid week with dry conditions continuing. Remaining warmer than normal through the end of the week with lighter winds. A strong upper level ridge of high pressure will bring continued fair skies and above normal temperatures through the short term period.
This will translate to possible afternoon and evening mountain showers, clouds and continued cooler than normal temperatures.
SHORT TERM (Now through Tuesday): Deep South Texas will remain between a large scale mid/upper level trough over the western half of the U. and a mid/upper level low over the northern Gulf of Mexico with weak mid-level ridging overhead through the period. Moist southeast flow in the low levels and southwest flow aloft will allow deep tropical moisture to increase across the region through the period.
239 AM EDT Mon Sep 25 2017 High pressure continues its dominance through mid week.
359 AM EDT Mon Sep 25 2017 A strong high pressure area will remain over the Mid-Atlantic region through midweek, then diminish and shift eastward. A mainly dry cold front will finally move into the region by the end of week bringing much cooler temperatures. Continued unseasonably warm, dry weather across the forecast area through midweek as a 590+ dm ridge slowly drifts eastward across the northern Mid-Atlantic region.
321 AM CDT Mon Sep 25 2017 Developing/approaching cold front makes its passage, wind shift, Tuesday night.
213 AM EDT Mon Sep 25 2017 Upper ridge continues its dominance.