Aikyam-Lab/Synoptic-Bench huggingface dataset:
Confidence tanks as there is a signal in the larger-scale models for a surge of convection over the Pennyrile and possibly southwest Indiana late this afternoon into the evening, as the cold front pushes eastward across the region. Temperatures Sunday night may approach the freezing mark, but winds will be sufficient to prevent frost except in the most sheltered of locations.
650 AM EDT Sat Apr 14 2018 A potent low pressure system carrying abundant moisture will bring showers and thunderstorms today and tonight. Widespread showers will continue into Sunday as the low progresses east.
As a result, the tornado potential is expected to increase further given the favorable conditions for streamwise vorticity ingestion into low level mesocyclones. Tonight, deep mid to upper level mid latitude cyclone continues to deepen over the area. As the pacific cold front catches up to the dryline, CAA will ensue into the area overnight into Saturday morning. Profiles gradually cool below freezing. During the transition, there will be a period of time with possible light freezing rain. However, this may be mitigated by the currently warm surface temps as they take some time to cool below freezing overnight. A rain/snow mix will transition to snow into mid morning time frame as profiles cool to well below freezing and the dendritic growth zone could become more saturated as the dry slot lifts to the to northeast of the area.
Upper ridging building along the eastern seaboard in response to large and powerful upper low and longwave from the Plains states into Northern Mexico today to produce very warm and humid conditions as southerly low level flow continues to increase mean layer moisture through tonight. Models continue in very good agreement that strong upper trough will translate eastward and be positioned from the Great Lakes into the Gulf of Mexico, and take on a negative tilt as intense mid-level height falls spread across the Deep South Sunday.
540 AM CDT Sat Apr 14 2018 A cold front is pushing through southwest Louisiana this morning. Drier and cooler air tonight as clouds will slowly dissipate and morning lows dropping into the 40s. The week ahead looks to be dry and on the cooler side with rains returning late in the week.
Then cold air filters into AR, with some freezing temperatures over northern parts of the state.
An upper low will then push the frontal boundary inland across the region Sat night and Sunday.
Another breezy to windy day with cooler, but still very dry conditions is on tap for west central Texas today. A cold front moved through the area tonight. On the backside of this low, strong northerly flow will persist. Look for highs mainly in the mid to upper 60s with a few readings in the lower 70s along the I-10 corridor, as northerly flow will continue advect in cooler air.
Warmer air moving in aloft will decrease lapse rates and felt the threat of significant snowfall is over and cancelled the advisories early. Strong northerly flow aloft on the west side of a deepening trough over the midwest, will continue overnight. Freeze Watches were upgraded to Freeze Warnings for the lower elevations in the vicinity of Moab, Grand Junction, Montrose, Cortez, and the Paradox Valley. High pressure will gradually build in from the Great Basin Saturday with a slow warming trend. The ridge with bring much warmer temperatures and dry conditions Sunday, then as the ridgeline passes overhead southwest winds will increase ahead of the next Pacific system.
Quiet and warmer weather can be expected today before the next storm begins to affect the region Sunday.
Patchy freezing drizzle is possible albeit not likely as temperatures cool in west central MO, since the warmest air aloft remains above the saturated layer and may allow a straight transition from drizzle to flurries.
308 AM MST Sat Apr 14 2018 Expect a warming trend this weekend with highs climbing well into the 80s today and into the low 90s on Sunday.
Unlike the last few days, winds will remain elevated after sunset as a slow moving cold front approaches from the west.
KGWX VAD wind profile showed only 10 degrees of directional sheer in the lowest 3 kft, with the top of this layer 50kts. The synoptic cold front will trail behind considerably, reaching the MS River at 3 PM. HRRR and RAP models depicted only light QPF ahead of the synoptic cold front over west TN and north MS this afternoon. Considerably cooler temps arrive on Sunday, with high temps as much as 20 degrees below normal under strong northwest flow aloft.
Currently, closed upper low over the Central Plains continues to bring severe winter weather to our south and southeast. High clouds associated with the upper low clearing over western ND with high clouds remaining over my central and east. Upper level low slowly moves east into the Missouri River Valley of Iowa and Missouri today, and will result in a continued decrease in cloud cover across the Northern Plains through the day.
303 AM MDT Sat Apr 14 2018 Light snow will end west to east today as the upper low pulls away and ridge builds from the west.
In fact little to support additional development until late aftn north of sfc warm front which will buck south later this morning in response to newd ejecting of upstream MCV. Lagging deep layer upper trough will pivot through the lakes Sun night through Mon aftn. This system lifts out slowly through New England Tue with fairly vigorous thermal ridging building quickly east out of the plains ahead of secondary wave digging through the upper midwest. IFR will continue through most of the period with surface warm front remaining south of both terminals and abundant moisture advecting into strengthening inversion.
416 AM EDT Sat Apr 14 2018 A potent low pressure system carrying abundant moisture will bring showers and thunderstorms today and tonight. Widespread showers will continue into Sunday as the low progresses east.
Ridging will continue to build into the area today, with warming temperatures. The northern zones where more moisture fell maybe a little cooler though as the added moisture will limit heating some. Going into Sunday the main ridge axis will be well into eastern Montana.
Temperatures will moderate on Sunday as models show a weak upper level ridge axis moving into the Front Range through the day.
322 AM CDT Sat Apr 14 2018 Strong upper level low pressure system along Nebraska-Kansas border will be edging slowly east while a tight northwesterly height gradient will be over the northeastern 3/4 or so of our area through early afternoon at least before edging east as well. This looks like a very good setup for a cold night - and guidance temperatures are consistently near freezing. So, we are forecasting sub-freezing temperatures tonight this area as well, but cannot justify including within this Freeze Watch. After the chilly start, it looks like a very nice day with temperatures recovering mostly into the lower 70s and winds remaining light.
temperatures will be much cooler on Saturday with highs generally in the 50s. As the upper low pushes through Saturday night. With low temperatures in the low 30s overnight Saturday. upper level ridging begins to build back over the area.
Tornado Watch was allowed to be dropped earlier than the original 6 AM CDT expiration time with just some lingering moderate showers and isolated storms along the cold front which continues to advance through the region. Gusty W/NW winds will follow in wake of the cold front so have issued a Lake Wind Advisory for the entire region until 7 PM this evening. Post-frontal temperatures will be noticeably cooler with unusually strong CAA occurring by mid April standards.
High pressure ridging aloft has allowed skies across the forecast area to clear out early this evening. mpj An upper level trof will continue to move eastward into the central Plains state today. A sharp upper ridge moves over the area overnight resulting in the potential for some fog over eastern and southern parts of our area. A few weak isolated rain and mountain snow showers will move across the area Saturday in association with a weak disturbance, but the bigger story will be the much warmer temperatures compared to the last few days across the region. Expect even warmer, even slightly above normal, temperatures Sunday, with just some passing showers and/or an isolated thunderstorm as deep southwest flow advects more clouds and moisture into our region.
Snow will persist into this evening as the upper low currently over northwest Kansas drifts east slowly and pulls the pcpn shield slowly eastward as well. Much quieter weather expected for the weekend as upper ridging sets up over the area. Milder conditions on Sunday with some increase in high cloudiness topping the upper ridge. Medium range models/ensembles in decent agreement with a large scale ridge dominating the CWA early in the week.
252 AM MDT Sat Apr 14 2018 Moisture wrapping around the back side of a deep upper level low over the plains will be gradually eroding today with scattered snow showers diminishing from west to east. Ridging aloft will be shifting eastward as the next upstream trough digs sharply across the Western States.
Cloud cover will increase heading into the dawn hours as a large low pressure system out west begins to move east. The forecast challenge heading into this event today will be high pressure and mid level ridging over the east coast as it will slow the approach of the front and rainfall in its approach eastward. Rain showers will be ongoing Sunday evening in an upslope flow/cold air advection regime as the previously mentioned upper low pushes east across the Ohio Valley.
400 AM EDT Sat Apr 14 2018 High pressure centered over the western Atlantic will extend west into central NC through this evening. A strong cold front will move east across the area Sunday night. High pressure will build into the Southeast U.
Waves of energy are expected to rotate around the developing upper low and across the region through Saturday. Meanwhile, theta-e advection will continue across central and into eastern South Dakota through tonight on north side of developing upper low.
High pressure aloft across the Great Basin will bring a warming trend to Utah this weekend.
This precipitation has been intermittently affecting the majority of the terminals today, and is expected to develop into a line of TSRA more less later this evening /progressing from west to east along a cold front/. Concurrently, winds will be shifting to the west-northwest with the passage of a cold front and thus could see -SHRA develop along the front, hence the insertion of the -SHRA/VCSH towards the end of the TAF period.
528 AM CDT Sat Apr 14 2018 Forecast discussion for routine morning forecast issuance An intense spring cyclone will produce strong winds and heavy snow through the weekend. A southern stream upper trough will slowly progress east from the Plains the next couple days. The initial cyclone with the trough has occluded and will weaken along the Iowa/Missouri border today. Strong lift generated just enough cooling aloft to knock out the warm layer, and cold dry air flowing in from the northeast kept the boundary layer AOB freezing across the area (though MTW just snuck up to 33F). We've been anticipating that, and initially expected the later rounds of precipitation with the triple point cyclone to be main show. So the second phase will be more of a typical long-duration snow event within the comma head of the cyclone.
By daybreak Saturday, showers and possibly some thunderstorms will move east across the area ahead of a cold front that will cross late in the day. Several shots of showers will be found after Saturday as upper level disturbances cross the region as they round a strong upper low anchored over the Midwest. The cold push will then nose even further south overnight, but readings along the Ohio River will still linger around 60 while the I-70 corridor holds closer to 50 degrees, and not too much further north of this drops into the lower 40s near a Celina- Wapakoneta-Kenton line. Closed low will pivot across the area early in the week.
The cold front will be along by daybreak shifting Southerly winds to Brisk NW10-20G30KT with clearing skies and VFR for Saturday.
At the surface, the closed low is located close to the NE/IA/MO/KS border. Behind the strong upper low, cold air pushes south of the CWA bringing well below normal temperatures for Sunday. Skies will gradually clear from west to east, but with the recent snowpack and northerly winds highs will only reach the lower 30s.
Overall the low associated with the system still is moving slowly east. However, the worst conditions, the more intense snow and the higher wind speeds and gusts held off a little longer due to the system being slower in moving east than previously expected.
Precip will push east as a cold front finally moves across the Tennessee Valley Sunday morning. The upper trough axis will swing through the area late Sunday, bringing cooler temperatures and maybe some light rain overnight.
312 AM CDT Sat Apr 14 2018 An upper level trough of low pressure remains over the central conus this morning with moderate snow, along with thundersnow occurring in southeast South Dakota. However, based on the 3 KM NAM and the experimental HRRR, higher amounts are possible in Deuel County due to easterly fetch of moisture and the Buffalo Ridge.
This is all in response to a vigorous upper level low pressure system movg across the central rockies and adjacent plains states today and tonight. This particular upper level low pressure system will continue to translate eastward across the central plains states through Saturday. The corresponding sfc cold front has tracked across the area with temperatures plummeting. The progged path of this upper level low pressure system suggests slgt chc pops through this evening for most of the fcst area except the southeast Texas Panhandle. In addition, freezing and below freezing temps are anticipated across most or all of the fcst area both Saturday and Sunday mornings, with freeze and hard freeze warnings tonight and Saturday morning.
The upper low is currently over the central Plains, and remains very strong. It looks to intensify slightly overnight, and remain a closed low for the duration of its impacts on the mid state. 5 inches across the area, and with the upper low/cold front approaching, the LLJ will increase in speed to 60 knots over the area. By sunrise on Sunday, the area looks to get between 2 to 4 inches, with the higher precip axis around 3 to 4 inches possible west of the Plateau and east of I-65.
A weak inverted trough remains along the ND/MT border late this afternoon. Strong low pressure over far southeast Nebraska is expected to linger over that area through tonight then exit eastward. Meanwhile, strong high pressure will continue to build over North Dakota, ending the snow over the southwest. Slightly warmer temperatures (mid to upper teens) far south central and southeast. High pressure remains over the area on Saturday.
Negatively tilted upper level trof and its deepening cutoff upper level low to track into northern IL by sunset Sunday.
Therefore, high temperatures should be a little warmer over the bare ground in the northern Red River Valley today.
1230 AM CDT Sat Apr 14 2018 Deep closed low aloft over the northwest Kansas is winding its way slowly to the east. The cold front will continue moving east on Saturday morning and should be through central Missouri by 15-16Z. Another round of thunderstorms is possible along and ahead of the cold front Saturday. and there is another severe threat over parts of central Illinois near the tipple-point just ahead of the low where mid level lapserates approach 9C. Think the primary threat will be large hail due to the steep lapserates, but 0-6km shear is approaching 50kts and the the cold/warm front interface will be near there as well which will add additional low level vorticity. Carney An upper trough and low pressure system will move across north central Missouri and western Illinois on Saturday night into Sunday.
Breezy westerly winds and scattered/broken mid and high clouds should remain common across the CWA into the overnight hours behind a cold front moving through the region.
134 AM EDT Sat Apr 14 2018 High pressure centered off the coast will continue ridging into the southeastern states through Saturday. A cold front will cross the area Sunday into Sunday night bringing showers and thunderstorms.
326 AM EDT Sat Apr 14 2018 Rain chances will increase over the weekend with the approach of a cold front. Eastern CONUS ridging should is expected to maintain dry weather for the majority of the area today, while temperature stays about 20 degrees above average with the region in the vast warm sector under the ridge. The models remain in general agreement that deep cutoff low pressure will emerge from the midwest and dig over the Upper Ohio Region for the start of the new week. The main rain event is progged later Sunday and Sunday night as the systems cold front squeezes eastward under a crossing southerly, moisture-laden jet. QPF amounts remain in dispute with the main point perhaps being that the upslope enhancement appears to capped via a strong inversion resulting from the warm advection on the low level jet.
Tonight's storms could still produce some isolated gusty winds and hail but tomorrow afternoon's threat will include an isolated tornado along the frontal boundary as weak low pressure moves along the stalled front over central Illinois. Warm front has drifted about 10 miles north of the far northern CWA border early this afternoon, roughly aligned just south of I-80.
A weak warm front will cross the area today, bringing sprinkles and light showers, mainly to the mountains. Clouds will remain around tonight and winds will increase in response to an approaching upper level trough, resulting in a mild night.
The stronger cold front has pushed off the coast and man was it a doozy. We look to be at least 10 degrees below average for the lows. Tomorrow looks pretty amazing as we continue with the northerly flow as high pressure expands across the region. Small Craft Advisory for all our Middle Texas Coastal Waters today as strong offshore flow develops in the wake of the cold front.
320 AM MDT Sat Apr 14 2018 Current surface analysis shows low pressure associated with the exiting storm system is centered over northwest MO. Weak high pressure is located over western ND. Upper level analysis shows low pressure over eastern NE. Pcpn continues to wrap around the low across eastern SD into central SD. Colder air will remain in place across much of the area, and combined with the new snow cover, temperatures will struggle to rise much above freezing across western SD.
438 AM EDT Sat Apr 14 2018 High pressure ridging into the area from the western Atlantic will move out to sea tonight. A strong cold front will cross the area Sunday bringing showers and thunderstorms.
Precipitation will be mostly snow, but may be mixed with sleet and freezing rain south of a Wisconsin Rapids to Green Bay line. It could be mixed with sleet or freezing rain across the east central portion of the state.
Clouds will increase around sunset tonight as the next cold front approaches from the west. Zonal 500mb flow will become more southerly this afternoon through tonight as an upper level low across the Plains moves eastward and strengthens. With increasing clouds and moisture, low temperatures will be warmer tonight compared to this morning, with lows in the lower to mid 60s. A +PV anomaly over the central Rockies this afternoon will swing into the Plains overnight and develop a strong cold front that will sweep into the southeastern U.
In fact little to support additional development until late aftn north of sfc warm front which will buck south later this morning in response to newd ejecting of upstream MCV. Lagging deep layer upper trough will pivot through the lakes Sun night through Mon aftn. This system lifts out slowly through New England Tue with fairly vigorous thermal ridging building quickly east out of the plains ahead of secondary wave digging through the upper midwest.
An upper level ridge axis will remain nearly stationary over the central and northern Rockies overnight and Friday. NAM, GFS, and ECMWF all showing another upper level wave rotating around this upper ridge axis and out into the Central Plains on Friday, however subtle differences on timing and track does exist.
956 PM CDT Thu Jul 27 2017 High pressure moving slowly southward into the region tonight will bring quiet weather. A sustained dry and cooler northeast flow will keep things quiet into Friday. Low level thermal trough sets up across the area with 925 temps in the teens celsius.
Relatively quiet period through the extended with upper level ridge across the southern half of the US retrograding back the west and expanding northward to cover much of the western half of the country.
At the surface, low pressure continued to develop in the Lee of the Rockies, with high pressure over Manitoba, the eastern Dakotas and Minnesota. Earlier development in southeast MT and northeast WY was associated with the latter cluster of impulses, and recent development from southeastern Montana through northeastern Wyoming to the Black Hills of South Dakota was tapping into the higher CAPE and bulk shear, along with enhanced mid-level lapse rates.
The cold front had finally entered into Northeast Oklahoma this evening. the cold front is forecast to move across Northeast Oklahoma and into Southeast Oklahoma and Northwest Arkansas by Friday morning. the drier dewpoints and cooler conditions look to be lagging behind the front a bit. lows in the low/mid 70s will remain possible.
Upper level ridge will continue to influence the western and central CONUS. The ridge extends initially from the Four Corner states-Southern Plains into the Northern High Plains Friday night. The upper level ridge will build westward this weekend and become more expansive over the Intermountain West extending into the Canadian Prairies. In the meantime, flow at low-levels will remain predominantly southerly over western NEB through the weekend owing to broad high pressure at the surface and at 850 hPa over the Upper Great Lakes and much of the Upper Midwest this weekend.
Will hold on to a low shower chance for a few more hours across central sections with any residual boundaries and some vort energy aloft with a mid level trough extending northeast from NE Florida.
The 00Z TAE sounding showed much drier air in place, and a peak at the lower and mid level WV channels of GOES-16 shows this low-mid level dry air extends across the majority of our forecast area. Showers and thunderstorms with the low combined with the East coast sea breeze will keep the highest rain chances in the eastern third of the CWA. Lows tonight will be in the low to mid 70s away from the coast.
A strong upper level ridge of high pressure over the Four Corners region will build into California during the next several days and bring generally dry weather and above normal temperatures to the district.
Some of this rainfall will likely drop into the Midsouth tonight, but more robust convection will likely await daytime surface heating and cold frontal passage on Friday. There is some diurnal component to this activity, although expect at least a scattering of showers and thunderstorms is remain most probable in vicinity to a approaching cold front later tonight. The big story is an end to the high heat and humidity of the last few days. Models are clear about the upper ridge retrogressing into the Rockys, leaving us in northwest flow. The climate prediction center is suggesting enhanced probability for cooler than average temperatures into early August.
A ridge of Atlantic high pressure continues to extend across South Florida into the Gulf of Mexico. This high pressure has produced the easterly flow which has reinforced the hot and humid conditions experienced over the last several days. As the week draws to a close, a low pressure area over eastern Canada pushes an associated frontal boundary towards the eastern seaboard of the United States on Friday.