Aikyam-Lab/Synoptic-Bench huggingface dataset:
The area will remain in deep southwest flow aloft ahead of a large mid level trough and closed low over the desert southwest.
Upper level low over northern Nevada continues to wrap some moisture back into southeast Oregon but will remain south of the forecast area. Water vapor satellite imagery showing upper low moving through Nevada. Upper ridge builds in Tue and strengthens Wed into Thu.
1221 AM EDT Tue Apr 27 2021 High pressure will prevail most of this week. A cold front could bring impacts to the region late in the week.
102 AM EDT Tue Apr 27 2021 Warmer and mainly dry conditions continue until the approach of a cold front late on Wednesday. High pressure will keep mainly dry conditions across the area overnight. Thus, will expect warmer temperatures tonight as most locations will remain in the 60s for lows and dew points rising into the upper 50s ahead of the change of air mass. Warm and moist advection in place on Wed, as cyclogenesis occurs and strengthens a deep SW CONUS trough upstream of the Ohio Valley. This environment, if it occurs coincident with a frontal passage courtesy of low pressure near Hudson Bay, would provide instability in tandem with frontogenesis and large-scale forcing for ascent, which would increase the likelihood for rain and thunderstorms.
Dry and warmer weather expected today and tonight. Water vapor imagery along with RAP analysis shows an increasingly amplified flow as a trough digs into the western US, with increasing heights across much of the eastern two-thirds of the CONUS. The ECMWF is a bit stronger with the 700-500mb ridge versus the GFS, however, the minor details really won't have much difference on sensible weather. Higher low-mid lvl RH's will advect into the area tonight which will bring an increase in cloud cover as the ridge axis begins to move east of the area.
SHORT TERM (Now through Wednesday): Deep South Texas and the Rio Grande Valley will remain on the northwest edge of 500 mb high pressure that will linger over the Bay of Campeche as closed 500 mb low pressure moves into New Mexico. Meanwhile, a persistent breezy to windy onshore flow, produced by high pressure over the Gulf of Mexico interacting with low pressure over Mexico, will generate slightly above normal daytime high and overnight low temperatures.
629 AM EDT Tue Apr 27 2021 High pressure offshore will maintain a warming trend this week.
/issued 310 AM CDT Tue Apr 27 2021/ SHORT TERM (Now through Wednesday): Deep South Texas and the Rio Grande Valley will remain on the northwest edge of 500 mb high pressure that will linger over the Bay of Campeche as closed 500 mb low pressure moves into New Mexico. Meanwhile, a persistent breezy to windy onshore flow, produced by high pressure over the Gulf of Mexico interacting with low pressure over Mexico, will generate slightly above normal daytime high and overnight low temperatures.
This trend of precipitation will continue ahead of a closed low and trough that is currently over Nevada and western Utah. The reason for this is that the closed low over Nevada will lose it's upper level support as a second shot of energy moves down the coast of California. Snow still remains in the forecast with several inches of snow for the higher elevations but as most of this snow will fall during the day and melt on roadways, minimal impacts expected. As one would expect, temperatures will be on the cooler side today under cloud cover and precip but will start to warmup by tomorrow and beyond.
Weak high pressure moving through the region today will begin a warming trend, that model guidance all agree on for this week. The broad high pressure ridge begins to take hold of the Northern Rockies on Wednesday, but the ridge axis remains to the west so westerly winds will again increase in the afternoon.
A late season storm system will bring cooler temperatures and a chance of showers and thunderstorms today and Wednesday. The second half of the week will see high pressure building in from the west, with dry conditions and a rapid warming trend into the weekend. Instability associated with the low will increase shower and thunderstorm chances this afternoon as it moves across southern Arizona over the next 24 hours.
Water vapor satellite imagery, heights, and lightning at the start of the shift had a closed low over northern Nevada with a ridge over the eastern U. A plume of moisture was noted ahead of the trough from northern Mexico into the Rockies and the Central/Northern Plains/Upper Mississippi Valley. Locally, the warm front reached parts of the forecast area with highs in the 70s and lower 80s from parts of southern Minnesota into northeast Iowa and southwest Wisconsin. Meanwhile, the 500mb trough over the Dakotas will shift southeast and deepen.
A low pressure system will produce scattered showers over southern Nevada and nearby areas before pulling away across southern Arizona tonight. Cool and unsettled weather will continue today as a low pressure system over our region slowly moves toward Yuma by this evening.
Showers have mostly come to an end as high pressure over the NE Pacific begins to build into the Pac NW.
Slightly warmer temperatures today are favored due to the much warmer start to the day (current temperatures are in mid 60s to near 70 degrees), some filtered sunshine, and surface winds veering a bit to a more favorable south/southwest direction. The NBM has continued to be on the warmer end of available model guidance, and therefore was heavily leveraged for this afternoon's high temperatures.
Expecting another dry, warm day across east-central FL as high pressure remains in control across the region. High pressure north of the region maintains dry conditions with east winds at 10-15 knots.
736 AM EDT Tue Apr 27 2021 Warm and dry conditions will continue until the approach of a cold front late on Wednesday. A broad high pressure ridge will maintain dry weather today. The tightening pressure gradient between Canadian Maritimes and Four Corners low pressure system will also increase wind, with afternoon mixing suppporting gusts of 20 to 25 mph.
955 AM EDT Tue Apr 27 2021 High pressure offshore will maintain a warming trend this week.
High pressure will build aloft over the region leading to warmer temperatures across the interior. Pleasant spring time weather in place for NW CA as high pressure builds aloft. Only remaining issue centers around cold morning temperatures across the interior valleys today as remnant cold air from the recent low pressure system combines with clear skies last night. However temperatures will rebound quickly later today and lasting through the end of the work week as strong ridging builds in over the West Coast and 850 mb temps rise to around 15 C. This will support afternoon high in the low 80s through many of the interior valleys for the remainder of the week.
Warmer temperatures expected today with highs in the 60s across most areas that see sun. Following another day in the 60s on Wednesday, even warmer temperatures are set to arrive in the latter half of the week.
325 AM MDT Tue Apr 27 2021 Even though the strongest signals for rain showers have moved to the south and east of our region, there still remains some general weak low pressure aloft from the Canadian prairie. Of greater concern is the return of fire weather concerns later this week as a strong ridge of high pressure builds into the region from the west.
409 AM CDT Tue Apr 27 2021 (Issued 409 AM CDT Tue Apr 27 2021) Today through Wednesday: A warm front ahead of approaching low pressure is currently sitting across the forecast area, with a fairy large spread in temps from north to south. The front will then sag back southward as the low moves through later today into tonight. Lowered temps Wednedsay from the previous forecast, as it's looking like southern Wisconsin will remain on the cooler side of the front through the day.
319 AM MDT Tue Apr 27 2021 Current GOES-E WV imagery showed the upper low centered over southern ID/northern NV. The attendant trough extended south into Baja CA. A cold front was located from northern IA, through central NE to the WY/CO/NE border. The cold front will drift further south into northeast CO today. The upper low to the west will track south and east through AZ and NM into Wednesday. Cannot rule out an elevated strong storm or two capable of small hail and gusty winds south of a Bridgeport NE to Cheyenne WY line where SPC has a Marginal risk. It will be much cooler today compared to Tuesday with 700mb temperatures cooling to -2C. A upper ridge builds along the Pacific coast Wednesday, resulting in a drier northwesterly flow aloft.
634 AM CDT Tue Apr 27 2021 We have a marginal risk for severe thunderstorms this evening in association with a cold front that will bring cooler temperatures to the region for the next few days.
Thunderstorm potential will increase tonight, especially toward and after midnight as the upper low, west of El Paso, approaches the region.
Issued by National Weather Service New Orleans LA 956 AM EDT Tue Apr 27 2021 This morning is starting out just a few degrees warmer than 24 hours ago. An upper level ridge centered around the Bay of Campeche is gradually spreading northeast towards the local area. Hence, slightly warmer temps now and this afternoon. We'll see highs more solidly in the 80s today as the upper ridge increases column heights. Dry weather conditions will be in place all through today and into Wednesday morning as high pressure ridging from out of the northeast continues to cover southeast Georgia and northeast Florida. High temperatures for today will reach up into the lower to mid 80s for inland areas and in the upper 70s along the coastline and areas affected by the afternoon sea breeze.
258 AM PDT Tue Apr 27 2021 Low pressure will linger through today bringing isolated showers and below average temperatures.
There are several boundaries interacting with the CWA as a low pressure system lifts thru the area. A thunderstorm has developed just south of a cold front in Yuma county with an eastward push. Easterly flow at the surface will eventually set up today, with W/SW flow aloft as 850/700mb low/trough sets up over northeast portions of Colorado. This will be aided by a push from a 500mb trough swinging thru the Rockies.
517 AM EDT Tue Apr 27 2021 Warmer and mainly dry conditions continue until the approach of a cold front late on Wednesday. High pressure will keep mainly dry conditions across the area through the predawn hours. Thus, will expect warmer temperatures tonight as most locations will remain in the 60s for lows and dew points rising into the upper 50s ahead of the change of air mass. Warm and moist advection in place on Wed, as cyclogenesis occurs and strengthens a deep SW CONUS trough upstream of the Ohio Valley. This environment, if it occurs coincident with a frontal passage courtesy of low pressure near Hudson Bay, would provide instability in tandem with frontogenesis and large-scale forcing for ascent, which would increase the likelihood for rain and thunderstorms.
/Issued 409 AM EDT Tue Apr 27 2021/ Another beautiful early summer day is on tap with mostly clear skies and temperatures in the low to mid 80s with cooler temperatures in the higher elevations of the GA mountains. As a trough approaches out of the SW tomorrow an influx of moisture into the upper atmosphere will bring high level clouds to the area but the best chance for precip will remain well north of us for the short term.
430 AM CDT Tue Apr 27 2021 We have a marginal risk for severe thunderstorms this evening in association with a cold front that will bring cooler temperatures to the region for the next few days.
A ridge extends from the Gulf of Mexico northwards across the Tennessee Valley into the Great Lakes with a broad upper level closed low across the western CONUS. The ridge axis is currently overhead but may shift to the east later today. Yesterday, highs climbed into the low 80s and expect temperatures will be a few degrees warmer today. At the surface, high pressure is out over the western Atlantic with Lee cyclogensis taking place out to the west. An upper low will track across Texas on Wednesday, and then details become a little more murky beyond this point. The GFS solution phases the upper low into the deeper trough, while the ECMWF separates the upper low from the parent trough, keeping the better forcing to our north.
An SPS was issued to message the lowered visibilities. Warmer temperatures expected today with highs in the 60s across most areas that see sun. Following another day in the 60s on Wednesday, even warmer temperatures are set to arrive in the latter half of the week.
A separate area of showers is noted between Mobridge, Pierre and Faulkton, working east-northeast as well. Also of note, portions of the Prairie Coteau and central SD is observing fog given the high humidity and light wind environment. As the low pressure system and upper-level jet energy only slowly shifts eastward today, the potential for continued unsettled weather conditions will continue through much of the day.
An area of low pressure was located over southwest IA and was responsible for more thunderstorm activity over the central Plains/Upper Midwest. Min temperatures to range from the middle 30s far north, to the lower 40s south. A weak area of high pressure is forecast to move into the western Great Lakes region by Wednesday afternoon and at least end the rain threat, although clouds may linger through the rest of the day. Max temperatures to range from the lower to middle 50s far north, to around 60 degrees west of the Fox Valley.
308 PM CDT Tue Apr 27 2021 As the night progresses the high pressure system that gave us pleasant weather over the last few days shifts further off the East Coast.
307 PM CDT Tue Apr 27 2021 A deep upper level low over the Desert Southwest is forcing cyclogenesis over the west central Great Plains. This has already spawned one bubble of low pressure which is moving northeast into Iowa at this time. Southerly flow ahead of the low is bringing deep moisture back into the Mid Mississippi Valley this evening, and clouds have been increasing all day today.
Temperatures begin to trend warmer through the weekend.
Models continue to show strengthening upper level ridge over the region Wed-Thu with warm temperatures.
155 PM MDT Tue Apr 27 2021 The cold front continues to slowly slide to the east with clearing skies and precipitation ending late this evening. Tonight a ridge will start to build into the forecast area, bringing drier weather and northwest flow. Overnight lows will be a bit cooler than today, but highs will start to rebound nicely on Wednesday.
Upper air analysis shows a broad ridge over the southeastern US and a deepening trof over the western US. At the surface, high pressure is situated off the Eastern Seaboard, while a frontal system is entering the Plains. Closer to home, a low stratus deck streaming across the area on the western edge of the ridge will persist overnight and into tomorrow, keeping warm and muggy conditions in place. Overnight lows are only expected to fall into the lower 70s tonight, while afternoon highs will top out in the mid to upper 80s tomorrow.
We have a marginal risk for severe thunderstorms this evening in association with a cold front that will bring cooler temperatures to the region for the next few days.
This has allowed temperatures to rise generally into the lower 80s at available land-based surface stations, with a few of the typical hotter spots in the mid 80s. Surface analysis shows a dome of high pressure centered southeast of the Carolinas. High pressure will slowly slide southeastward towards the Florida Peninsula today, but this will be somewhat offset by heating over the Florida mainland. As the high continues to build southeastward this evening, fresh to strong easterly breezes will commence, and Small Craft Advisories are expected to be required for most or all Keys coastal waters by this evening.
High pressure off the Carolina coast this afternoon should continue to drift east over the next couple of days. Afternoon temps today have reached the low 80s along the coast and low/mid 80s inland. Temperatures on Wednesday will be a bit higher, reaching the low/mid 80s along the coast and mid/upper 80s inland. Tonight, expect overnight lows in the low to mid 60s, though a few rural inland spots could drop into the upper 50s.
North of the front, temperatures were in the lower to mid 60s. This would result in scattered showers and isolated thunderstorms generally focused near the Highway 20 corridor. The frontal boundary is forecast to sag southward to about the Highway 30 corridor or along a line from Cedar Rapids to Sterling Rock Falls.
/issued 1030 AM CDT Tue Apr 27 2021/ Today should be warm with temperatures getting into the low 80s. High pressure was located off of the North Carolina coast and will keep dry weather over the region today. Temperatures will be on the warm side today with highs in the lower 80s.
The forecast area is experiencing these warm temperatures under a broad upper level ridge. This ridge extends from the Gulf of Mexico northwards into the Great Lakes region. The upper pattern is fairly amplified with a deep closed low across the Desert Southwest. At the surface, high pressure is centered out over the western Atlantic with a broad area of low pressure across the central and southern Plains. Overnight lows will only drop down into the low to mid 60s.
Though the sfc boundary will slide southeast of the region tonight, the H850 boundary/trough will remain over the region through midday Wednesday.
Fair weather and warm temperatures will continue with deep layer ridging in place. Lows tonight will be in the lower to mid 60s with highs Wednesday in the mid to upper 80s inland areas and near 80 along the coast.
The lower clouds are breaking up a bit as some mid or high clouds move into the area. An upper level trough is poised to move through the forecast area tonight. As the trough moves through, there will be an increasing chance for showers and thunderstorms. The CAMs are fairly consistent with initiating the activity on the high Plains and moving it into the area. Overnight, as the upper level trough moves into the area, there will be some showers and thunderstorms across the area. These will continue into Wednesday, but during the afternoon should diminish as the trough moves further to the east.
256 PM CDT Tue Apr 27 2021 A weak cold front will move through the area on Wednesday, bringing breezy winds, drier air, and a slight chance for some light rain showers. The low over southern Alberta will develop into a weak Clipper system as it quickly moves east- southeast overnight and into the Northern Plains by Wednesday morning. The cold front associated with this system will bring breezy westerly winds through the day tomorrow, becoming northwesterly by Wednesday evening.
301 PM CDT Tue Apr 27 2021 After a very warm, sunny, and breezy day across central Illinois today, the chances for showers and thunderstorms will increase tonight into Wednesday as low pressure moves slowly across the region.
We are entering a period of relative benign weather for the next couple of days as high pressure will gradually build over the region.
This is a sign of the southward progression of the mid- and upper-level ridging. With the aforementioned ridge building in, expect a commencement of breezy conditions later this evening, lasting through at least Wednesday night. As the ridge slowly slides southeastward later this week, winds will gradually clock southeasterly.
RW Extended models continue to show good agreement initially, then begin to diverge with large upper level trough as it moves through the region late in the week.
Forecast Summary: A chance for showers and thunderstorms will remain in the forecast through Wednesday as a cold front and upper level system interact across our region.
Midlevel cyclone should further consolidate over the Four Corners/desert SW this evening into tonight, taking the bulk of forcing for ascent south of our region and bringing an end to most precip aside from lingering light showers near the NE border. Another trof and weak front cross the region tomorrow, with the bulk of associated pressure rises and strongest BL winds remaining to our north.
The deep upper low pulling the moisture into the Permian Basin is only slowly moving east so the severe weather threat will continue across the area through early Wednesday morning. Wednesday we will be in the dry slot of the upper low keeping rain chances mostly to our east and north.
would think the CAPE is going to begin coming down as well as we are seeing temperatures only in the low 40s across Laramie County and low 50s at Kimball and Sidney.
/Tonight through Wednesday Night/ A longwave trough continues to slowly make its way across the lower Intermountain West, advecting Pacific moisture through mid-level southeasterly flow across the Ark-La-Tex. Ongoing southerly surface flow will also moisten the lower level of the atmosphere in advance of the next frontal boundary. With this type of air mass in place for the next 36 hours, temperatures will be moderated into the low 70s and mid-to-upper 80s.
Cooler air aloft have steepened mid level lapse rates to 7-9 deg/km, with SBCAPE values of 250-500 J/kg across the region. By mid to late morning, moisture wrapped around the northern periphery the low will spill back over the Divide resulting in an uptick in shower activity across the central mountains. Moisture source and shower concentration will shift south by Wednesday afternoon, tracking with the low. The low drifting further south and east from the CWA will leave the entire region under dry northerly flow and clearing skies overnight.
930 AM PDT Tue Apr 27 2021 The trough of low pressure will bring another chance of showers this afternoon with a slight chance of thunderstorms, mainly in and near the mountains.
Unfortunately, uncertainty continues to be fairly high for such a short term forecast, but overall, the trend continues toward the higher flooding and conditional severe threat being tomorrow and tomorrow night.
Our second round of severe weather also remains on track for later this evening as the dryline surges back westward and meets up with an approaching Pacific cold front.
Wednesday, weak high pressure will build into southern Wisconsin. Daytime high temperatures will be cooler than today, but doable, with highs in the low 60s for most.
350 PM CDT Tue Apr 27 2021 High clouds continue to stream in overhead, with broad isentropic ascent in place ahead of the deep trough over the Southwest CONUS. Between the two, a cold front lies across northwest Kansas, with a dryline stretching from north-central Kansas into western Texas. Despite the high clouds, temperatures have warmed into the mid to upper 70s, while gusty southwest winds have brought dewpoints into the 60s east of the dryline. Conditions should turn drier for the end of the week and into the weekend, as the upper trough gets cut off over northern Mexico and ridging builds in over the Central Plains.
1205 PM EDT Tue Apr 27 2021 Warm and dry conditions will continue until the approach of a cold front late on Wednesday. A broad high pressure ridge will maintain dry weather today. The tightening pressure gradient between Canadian Maritimes and Four Corners low pressure system will also increase wind, with afternoon mixing suppporting gusts of 20 to 25 mph.
As this area of low pressure strengthens into Wednesday, winds will continue to increase across the region. Wednesday highs will reach the low 100s out west with most areas seeing upper 80s to mid 90s. Central and western portions of the CWA will see heat indices in the low 100s due to the combination of high temperatures and relative humidity. A cold front will begin to approach northwestern portions of the CWA by Wednesday morning with rain and thunderstorm chances increasing overnight ahead of the front.