Aikyam-Lab/Synoptic-Bench huggingface dataset:
Even with the cloud cover, overnight low temperatures should also be trending cooler east of the Cascades Sunday night. By later Monday, we'll still be under north to northwest flow as an upper level ridge builds in over southern Oregon. In addition, a thermal trough will build along the southern Oregon coastline.
A few showers or an isolated thunderstorm may continue to loiter over parts of eastern NV this evening as an upper level low pressure system exits the region. High pressure returns with a warming trend starting on Monday.
1012 PM EDT Sun May 2 2021 Humidity will begin to increase as high pressure moves farther offshore.
738 PM EDT Sun May 2 2021 MSAS analysis a surface pressure trough extending SW from Wisconsin into the Central Plains which marks the location of a surface warm front. Given that the fgen band placement tomorrow will be at least partially a function of how convection over the High Plains evolves tonight, confidence is on the low end. Ridging out west with broad troughing over the eastern U.
648 PM CDT Sun May 2 2021 (This evening through Monday Night) Upper low over southeastern OK early this afternoon will move away from the fa the rest of this afternoon and tonight ending the chances for rain in eastern parts of the fa. However, the higher potential for showers/storms will likely be behind the front as the wave moves across the region.
533 PM MDT Sun May 2 2021 Some stronger thunderstorms are currently moving through southeast Wyoming and western Nebraska bringing gustier winds and small hail as a cold front is passing through. The time range with the highest impacts expected is tonight after sunset, especially for the I-80 Summit.
731 PM EDT Sun May 2 2021 Humidity will begin to increase as high pressure moves farther offshore.
953 PM EDT Sun May 2 2021 Sped the high PoPs up again and hour or two based on radar. The leading edge of the rain shield is now as far north as southern Carroll county with some breaks in the rain, but still fairly solid with heavier activity upstream over the Tennessee Valley and Ozarks, along and ahead of the negatively-tilted upper trough. Showers will overspread the area tonight as a weakening upper level wave pulls northeast out of the Red River Valley into the lower Ohio Valley. Mid and upper level ridging moves through the area in the wake of the upper wave midday into late afternoon Monday, which will likely bring at least occasional breaks in the precip as a moderate midlevel subsidence inversion develops.
837 PM EDT Sun May 2 2021 Approaching low pressure will bring showers and thunderstorms back to the region starting later tonight, with rain chances continuing through the first half of the week. The 00Z PIT sounding shows that a good amount of dry air exists in the low and mid levels that will erode the leading edge of the rain as it moves north. The trough is progged to cross the Upper Ohio Valley region Monday, continuing the showers.
BVO may be the exception and hold onto MVFR through the end of the period as precip chances will be possible near the Kansas border in response to a cold front pushing into the region Monday afternoon. /Issued 631 PM CDT Sun May 2 2021/ Showers in association with an upper level low pressure system moving northeast into central AR have for the most part dissipated. This decaying complex will leave an outflow boundary across southeast Kansas/northeast Oklahoma which will help enhance a cold front that is set to move into eastern Oklahoma Monday. The airmass across the area is expected to becoming increasingly unstable Monday afternoon/evening as surface dew points climb into the mid 60s to lower 70s in advance of the cold front. This could allow a few surface based storms to develop in the vicinity of the cold front.
As a trough to our east digs into the Great Plains, the flow aloft will become stronger and more northerly, keeping the evening into the morning dry and quiet. Late Monday night onward looks to be dry as strong ridging settles in.
509 PM MDT Sun May 2 2021 The leading surface cold front has passed through most of the forecast area early this afternoon, currently located from west of Winner to Valentine, and continuing to move southeastward. The secondary cold front, with stronger low level cold advection producing gusty northwest winds, currently extends from near Philip to Custer. The moist airmass, combined with instability due to diurnal heating and lift enhanced by CAA aloft, as well as an upper trough crossing the region, has created scattered to numerous showers, and a few thunderstorms today.
Moistening of the low levels will then result in a steady drop in ceilings around or shortly after 12Z, with low end MVFR and IFR conditions in light rain becoming more probable. By late tonight, a more widespread rain will likely spread into the southern part of the area as upper low over northeast Texas opens and lifts into the Ohio Valley.
/issued 134 PM CDT Sun May 2 2021/ An upper level short wave trough will move southeastward over the Great Basin tonight and across the Rockies on Monday while modestly staying in phase with another trough in main jet stream moving across the southern tier of Canada. This combination will unlock the next cold front and decent amount of cold advection through the forecast area during the day Monday. Ahead of the cold front and with a continuation of height and surface pressure falls overnight, winds are likely to remain a bit breezy through the night limiting cooling overnight somewhat. Increasing mid level ascent ahead of the approaching upper trough combined with some frontogenetical forcing behind the cold front should be enough to generate at least scattered convection as early as late morning, potentially increasing through the afternoon.
Otherwise west winds will increase around 15Z Mon with a cold front expected between 00Z-03Z/Tue HOB/MAF/CNM. /issued 235 PM CDT Sun May 2 2021/ The upper low that brought much of the area very beneficial rain the last few days is on its way out soon to be replaced by another trough to our west. The strong winds will continue into this evening, especially in the higher terrain. The next trough will move across the area Monday shoving a Pacific front through.
Given the low level dry layer and weak inversion already set up across the area, our chances for precipitation will be severely limited.
402 PM PDT Sun May 2 2021 A weak ridge is expected overnight for the region.
Drier and warmer conditions are expected midweek as a ridge of high pressure rebuilds into the area. Cooler and unsettled conditions are expected for the later half of the week as a broad area of low pressure affects the Pacific Northwest.
631 PM CDT Sun May 2 2021 Showers in association with an upper level low pressure system moving northeast into central AR have for the most part dissipated. This decaying complex will leave an outflow boundary across southeast Kansas/northeast Oklahoma which will help enhance a cold front that is set to move into eastern Oklahoma Monday. The airmass across the area is expected to becoming increasingly unstable Monday afternoon/evening as surface dew points climb into the mid 60s to lower 70s in advance of the cold front. This could allow a few surface based storms to develop in the vicinity of the cold front.
522 PM MDT Sun May 2 2021 The cold front that brought the cooler air continues to drag through the area. Scattered showers across the north will continue as the upper-level trough continues to support upward motion. With the cooler air in place, some snow flurries could mix in tonight in the basins. Snow showers will continue in the higher elevations through the period as upslope will support those showers.
A passing trough will bring a chance for light showers and briefly cooler weather tonight and Monday before warm weather returns through much of the work week. Radar indicates scattered showers and thunderstorm are developing over southern Utah this afternoon ahead of the trough axis.
240 PM PDT Sun May 2 2021 A weak ridge is expected overnight for the region.
BT Satellite imagery shows broad troffing/cyclonic flow over the region, with strongest energy over the central Rockies and another wave dropping thru the northern Rockies.
A progressive negative tilted upper trough over Arkansas will lift northeast toward the Ohio Valley overnight. An upper level trough will move toward the area through the next 24 hours with increasing convection.
During this time, roughly 400 to 800 J/kg MLCAPE is shown on NAM soundings, along with roughly 35 kts of shear in the low to mid levels. The better forcing will be to our northwest, closer to the low, which aligns with the day 2 slight risk area. Instability will be increasing areawide during the afternoon as the surface temps warm and the low/mid level lapse rates steepen. Showers and storms should continue into the evening hours across the eastern Tennessee Valley as a weakening upper level trough begins to shift east of the Appalachians.
High temperatures today will be cooler behind the fronts, in the mid 60s to mid 70s F on the plains. Lows tonight will also be cooler but should be insulated by mostly cloudy to overcast skies overnight, with lows in the low 40s F on the plains and upper 20s to mid 30s F in the mountains. By Monday night the upper level trough will be in place over eastern CO. Moisture and weak northeasterly upslope will continue along the foothills into the evening hours on Monday keeping light snow over the higher terrain and some rain possible along and west of I-25.
121 AM CDT Mon May 3 2021 /Updated at 0100 AM CDT Mon May 03 2021/ A warm front is now north of much of Central Alabama, stretching from Huntsville to Auburn.
A passing trough will bring a chance for light showers and briefly cooler weather tonight and Monday before warm weather returns through much of the work week. A trough approaching the region from the north has led to some isolated to scattered sprinkles or light showers this evening from around I-40 northward. Radar indicates scattered showers and thunderstorm are developing over southern Utah this afternoon ahead of the trough axis.
208 AM MDT Mon May 3 2021 Water vapor shows trof axis extending from the Northern Plains into the Four Corners region, with upper ridge along the west coast. Slightly warmer temps expected on Tuesday with return flow.
By this evening and overnight, expecting the upper trough of this system to start digging through and increasing our rain chances across our area, with the highest POPs generally north of I-40.
Highs on Monday range from the lower 80s near the coast to the mid to upper 80s further inland. At the surface, the low pressure system will move from eastern Oklahoma toward the Ohio River Valley. A cold front associated with this will also begin traversing the ArkLaTex region by this time. Model guidance indicates a line of showers with embedded storms moving over the Deep South from Tuesday afternoon as the cold front approaches from the northwest. 6 C/km, but the low level lapse rates range from 6. Highs Tuesday afternoon will be in the lower to mid 80s.
The forecast area is between a pair of upper level short waves this morning, while at the surface an inverted surface trof was found over the western edge of the area. A closed upper low, typical of winter, will meander around northern Manitoba tonight. This low will send an additional short wave through the region, keeping the chance of showers/sprinkles going near the Canadian border, as well as over north central Wisconsin. A dusting of snow is possible over the higher elevations of northern Cook County. On Tuesday, the closed upper low drifts into northwest Ontario. Embedded impulses around the base of the upper low will cross the international border with more showers/sprinkles. Dry elsewhere as high pressure arrives. The closed upper low drifts a bit farther east Tuesday night allowing the Northland to be influenced by the high pressure ending all precipitation.
1142 PM EDT Sun May 2 2021 Approaching low pressure will bring showers and thunderstorms back to the region starting later tonight, with rain chances continuing through the first half of the week. The trough is progged to cross the Upper Ohio Valley region Monday, continuing the showers.
As the trough lifts to Lake Michigan today, expect occasional showers to clip the far southeastern part of the area. High temperatures will top out in the low to mid 60s today, but brisk northwest winds related to the tightening surface pressure gradient will make it feel a tad chillier. We will have to watch for the potential for patchy frost in west central Minnesota tonight, where lows look to dip into the low to mid 30s.
323 AM CDT Mon May 3 2021 Little has changed in today's forecast: storm development is still highly contingent on the strength of forcing along the cold front as it drops through the region. A baroclinic boundary currently draped through South Dakota and Iowa will drop southeast today as a cold front, moving through the forecast area this afternoon and evening. Shear within the lower levels is expected to be largely parallel to the front, indicating that some storms could merge into linear segments. Mid-level ridging over the region during the day will attempt to stunt widespread storm development. While the mid-level ridging will limit widespread linear development, the environment is favorable for discrete storms to form initially off of the front before merging into small linear segments.
1128 PM MDT Sun May 2 2021 Some stronger thunderstorms are currently moving through southeast Wyoming and western Nebraska bringing gustier winds and small hail as a cold front is passing through. The time range with the highest impacts expected is tonight after sunset, especially for the I-80 Summit.
CLouds will try to scatter out some this afternoon, but northeast Oklahoma sites might stay in MVFR all day with as approaching cold front moves into the area this afternoon. /Issued 631 PM CDT Sun May 2 2021/ Showers in association with an upper level low pressure system moving northeast into central AR have for the most part dissipated. This decaying complex will leave an outflow boundary across southeast Kansas/northeast Oklahoma which will help enhance a cold front that is set to move into eastern Oklahoma Monday. The airmass across the area is expected to becoming increasingly unstable Monday afternoon/evening as surface dew points climb into the mid 60s to lower 70s in advance of the cold front. This could allow a few surface based storms to develop in the vicinity of the cold front.
415 AM EDT Mon May 3 2021 Skies range from partly to mostly cloudy in the Lower and Middle Keys to mostly clear in the Upper Keys along with southeast winds averaging near 15 mph. Because of this featuring migrating and weakening, a strong anticyclone just to our east will expand back and over South Florida, the Florida Keys and the adjacent waters through this forecast period.
Moistening of the low levels will then result in a steady drop in ceilings around or shortly after 12Z, with low end MVFR and IFR conditions in light rain becoming more probable. By late tonight, a more widespread rain will likely spread into the southern part of the area as upper low over northeast Texas opens and lifts into the Ohio Valley. The surface front will settle just south of the region into Tuesday in the wake of the Monday low pressure system.
312 AM CDT Mon May 3 2021 Latest radar imagery shows a few showers over NW Iowa and NE Nebraska, associated with a cold front that continues to depart the region. As a result, expect highs to remain on the cooler side (compared to the last few days), with temperatures forecast to only climb into the upper 50s to low 60s. Given that winds will be light, wouldn't be surprised to see some frost develop in those areas near freezing.
With this surface pattern in place and weak ridging aloft, today's highs will be well above normal under clearing skies, with mid to upper 90s expected for the Rio Grande Valley and coastal counties and 100s for the rest Deep South Texas. A weak cold front will pass through on Tuesday as a mid level trough moves across the Southern Plains and pushes the mid level ridge further east.
309 AM CDT Mon May 3 2021 Upper level trof moving over the region early today will depart to our northeast. Scattered showers (possible thunder) will depart with the trof, resulting in a lull in convection later this morning through early afternoon. Other solutions show development (initiation) farther south toward the Ohio River this evening, with a more organized area of convection, possibly severe with damaging winds moving ENE from the southern Plains across the Ozarks toward the Lower Ohio Valley (our CWA) overnight.
However, the potential for lightning will likely increase through the evening as the upper low gets closer to the area and destabilizes the airmass mainly over the eastern half of the forecast area. Much of the rainfall will subside by late tonight after the upper low moves northeastward from southwest AR into southeast MO. Expect the peak in storms Monday evening as a cold front moves through the region. Storms will be ending from west to east as the upper level trough associated with Monday's cold front passage moves east of the area.
352 AM CDT Mon May 3 2021 The short term will be relatively quiet as the cold front continues to move east. This evening, an upper level trough, currently centered over the Great Basin, will move southeastward over the southern Rockies and leave west and north central Nebraska with a much calmer wind regime and clearer skies in its wake. The combination of the two creates for much cooler overnight temps in the low- to mid- 30s. Into the day Tuesday, highs will reach into the low to mid 60s, which is only a couple degrees below normal for this time of year.
- Cooler weather to return on Tuesday, lasting through the week.
Sufficiently strong deep-layer shear of 40-50 knots will coexist with a 30-40 knot low- level jet to promote storm organization and mesocyclone development, especially across the western third of the forecast area where inflow parcels will be a bit more unstable than points further to the east. The warm front lifts north through Alabama into Tennessee Monday morning, bringing with it a much more unstable, warmer and more humid air mass. Due to the nature of the air mass, I'm more confident in thunderstorm development along the warm front around 5 AM Monday morning. Tuesday, the cold front arrives.
1235 AM EDT Mon May 3 2021 MSAS analysis a surface pressure trough extending SW from Wisconsin into the Central Plains which marks the location of a surface warm front. Given that the fgen band placement tomorrow will be at least partially a function of how convection over the High Plains evolves tonight, confidence is on the low end. Ridging out west with broad troughing over the eastern U.
An upper level low pressure system will continue to bring cool and unsettled weather to the area through Monday. A drying and warming trend will follow for midweek as high pressure builds across the region. An upper trough continues to carve into Utah this evening. The associated cold front has already pushed through Utah, with predominantly north to northwesterly winds currently in place across a majority of the forecast area. Lingering showers continue across the area, the bulk of it across southern and eastern Utah near and behind the cold front. Otherwise, as the trough continues to shift southeast, winds will become increasingly easterly across northeast Utah and southwest Wyoming tonight.
Gusty northerly winds likely through Monday resulting in increased fire weather concerns and warmer temperatures. Winds will decrease Mon afternoon as the Ern Pac ridge axis moves closer to the coast. But another round of Nly barrier winds is forecast Mon nite into Tue as high pressure builds and pressures rise over the Pac NW and Great Basin. Temperatures will be warmer, humidities lower and gusty northerly winds will again increase fire weather concerns on Monday.
A progressive weather pattern will remain over the region through Tuesday, bringing periods of precipitation with cooler than normal temperatures.
300 AM CDT Mon May 3 2021 An upper level trough will move into the Four Corners region this morning and slowly start to lift toward the central plains by this evening. A lead area of lift is making its way through central NM early this morning while a cold front surges south out of the Texas Panhandle. Precip will have moved off to our east along with the axis of the upper trough.
Meanwhile, surface observations indicate a low between Yankton, SD and Norfolk with an associated quasi-stationary boundary stretching northeast and southwest from the low. Tuesday: A temporary period of mid-level height rises will translate to dry weather on Tuesday with highs in the low to mid 60s.
1043 PM MDT Sun May 2 2021 The cold front that brought the cooler air continues to drag through the area. Scattered showers across the north will continue as the upper-level trough continues to support upward motion. With the cooler air in place, some snow flurries could mix in tonight in the basins. Snow showers will continue in the higher elevations through the period as upslope will support those showers. As the trough continues to dive southward and fill, a trailing wave sweeps across the northern Rockies into WY, bringing another round of showers and mountain snow.
345 AM CDT Mon May 3 2021 WV imagery shows the upper trough approaching the Four Corners, leaving southwest flow aloft over West Texas and Southeast New Mexico. The latest NAM shows the mountain wave signature diminishing over the next few hours, and the High Wind Warning will be allowed to expire at 11Z as a result. Area radars show a prefrontal trough has just passed through KLBB, and fropa looks to have occurred in KAMA.
313 AM CDT Mon May 3 2021 Remnants of the decaying MCS from earlier in the evening continue to push into northeast Kansas this morning as the upper trough axis rotates through the Central Plains. The progressing cold front currently observed from south central through north central KS is on track to march southeast throughout the morning. Cool air advection also follows the boundary, resulting in temps from the low 60s in north central KS to the low 70s over far east central KS. A secondary upper trough axis enters the high plains this evening, as the mid level baroclinic zone sets up over southern KS into MO.
903 PM PDT Sun May 2 2021 A departing upper level trough over the western part of the country will lead to breezy conditions with temperatures creeping closer to average. Warmer and drier weather is in store into the middle of the week as an area of high pressure to our southwest moves over the region. Slightly cooler weather with westerly breezes are possible as we round out the upcoming week.
Presently, an upper trough is working its way across the region that is providing the energy for these cells during the next several hours. The severe potential will extend into the evening as the surface boundary finally inches its way across Middle Tennessee with the upper trough following shortly thereafter.
306 AM EDT Mon May 3 2021 An U/L disturbance will dig over the southern plains today and tonight and will induce downstream ridging over the Bahamas and Florida peninsula. The U/L ridge will hold over the region through midweek.
Today will be slightly warmer as highs approach 60 degrees.
Texas is between two upper level troughs this morning with nearly zonal flow in place. High pressure over the Gulf has the low level flow from the south over the eastern half of South Central Texas while the western half is has less well defined winds in a transition to low pressure farther west.