Aikyam-Lab/Synoptic-Bench huggingface dataset:
An upper level low is currently situated near the tri-state border of North Dakota, South Dakota, and Montana. This low will continue to gradually move east and then northeast through the rest of the afternoon and tonight before vacating into northern Minnesota and eventually southern Ontario as an open wave. Behind the upper low, subsidence will lead to diminishing clouds from west to east late this afternoon through the overnight hours. We transition to quasi-zonal flow aloft on Tuesday, which will promote mostly sunny to partly cloudy skies and warmer temperatures with highs in the mid to upper 70s. Expect slightly cooler temperatures on Wednesday (lower 70s west to upper 70s east) with a few more clouds.
An area of high pressure at the surface will build into western Kansas today as an upper level trough very slowly moves across southeast Kansas and Oklahoma. Subsidence developing behind this upper level system today will bring some sun and warmer temperatures to western Kansas. Across south central Kansas where cloud cover will linger through at least late day the highs will only warm into the mid 70s. Tonight an upper level low will begin to develop over southern Oklahoma and North Texas with some moisture and lift developing just north northwest of this developing upper level system. The upper level low will remain nearly stationary during the day on Wednesday. Late week the upper low over the Southern Plains will move into Arkansas and Louisiana as an upper level trough exits the Rockies and moves across the Northern and Central Plains.
While southeast KS will maintain the higher rainfall chances, not expecting anything this afternoon or tonight as widespread we are seeing right now. One change from yesterdays' models run is a further north placement of the upper low. By 12z Wed, most models now have the low situated over southeast OK. ECMWF and GFS have come into much better agreement now with how the upper low will depart. So at this point confidence is high in dry conditions for the Fri-Mon time frame as we get some upper ridging building over the Plains to start the work week.
This will continue the pattern of afternoon and evening showers and thunderstorms around the Midwest, as Low pressure lingers across the eastern Plains. This Low will begin to shift slowly north northeast tonight, bringing a better chance for widespread showers and thunderstorms to central Illinois mid-week.
The 12Z TAE RAOB showed some dry air in the low levels so gusty winds could occur again today with strong/taller storms. A closed low drifting over SE Texas along with a ridge of high pressure over the eastern US will keep moist southerly flow in place. Tuesday will be a bit cooler with cloud cover and precip keeping the highs in the low to mid 80s, or even upper 70s in the northern zones.
Do have a gradient from west to east with the higher temps in the west, where they have the best chance for sun and lacking precipitation. This morning's system will continue to track north, slightly northeast into Iowa and further northeast, however, much of the guidance indicates that as lobes of vorticity spin around the cut-off low over the Southern Plains, some of the moisture from the system that moved east of the area today, will get wrapped back around to the south. Thankfully, at least much of the area with continued chances for light rain have received the lower amounts over the past 5-6 days, which will help.
350 AM CDT Tue May 26 2020 An upper level trough is over the central part of the country.
1149 PM MDT Mon May 25 2020 Brisk nly flow at the surface and aloft across the area today behind departing upper trough. Will keep a low chance for convection going into the evening over the higher terrain, though anything that develops at this point will be spotty and weak. Skies clear after sunset with winds decreasing, and many mountain valleys will drop to near or below freezing by early Tuesday morning. Upper trough and developing low sink drift slowly sewd into TX on Tue, keeping CO under nly flow another day.
A deep, negatively tilted trough covering a good portion of the Gulf of Mexico and across the Florida Peninsula will lift northward and weaken.
Breaks in the rain will become more frequent later this morning through this afternoon across the region; however, moisture and some elevated instability will wrap around the back side of the low and reinvigorate showers across central KS this afternoon and evening, providing another opportunity for up to another inch of rainfall in areas. As a result of these continuing rain chances and the low flash flood guidance across the region, will continue the Flash Flood Watch through today for all areas.
Upper level ridge building offshore later Tuesday with the ridge shifting over Western Washington Wednesday.
WV satellite reveals longwave trough over the High Plains extending southeastward over N TX and OK. A series of waves from NE NM into central TX are seen in the cyclonic flow around the base of this trough, with the most vigorous of these kicking off thunderstorms across central TX. For Tuesday and Wednesday, expect an upper low to cut off from the main flow over N TX and slowly churn eastward. The eastward trend in the upper low has reduced available wraparound mid level moisture over the CWA.
Given this tropical airmass and a weak trough in the area in conjunction with daytime heating, a fairly high coverage of afternoon showers and thunderstorms is expected with PoPs around 60% for a large portion of the day.
149 AM EDT Tue May 26 2020 High pressure will maintain generally dry and warm weather through Wednesday.
A more typical summerlike pattern is expected on Wednesday with the state in between a large cutoff low centered over the Southern Plains and ridging over the western Atlantic. The highest coverage for afternoon showers and thunderstorms on Wednesday is expected to be over the interior and Lake Region with high temperatures ranging from the mid 80s to low 90s.
Looking at another day of high temps topping off in the low to mid 80s with dewpoints in the 60s. The warmer temps and ample moisture will help MLCAPE climb to around 1500-2200 J/kg this afternoon and combined with synoptic scale lift from the diffluent flow aloft, could see some convective showers develop through the afternoon. Similar setup expected for Wednesday with southerly flow and daytime temps topping off in the low 80s.
1258 AM CDT Tue May 26 2020 A cold front associated with the upper low stalled near the vicinity of the region is pushing through the area currently and should keep most of the showers around the Arklamiss overnight with little additional threat through at least early morning of significant precipitation.
(Today and tonight) With the continued shift of the upper level cyclone eastward, precipitation chances continue to shift with it.
An approaching cold front in association with a low pressure up in Saskatchewan will pass through the region Wednesday afternoon limiting daytime highs in the low to middle 70s across SE WY and upper 70s and around 80 in NE.
This low was in the process of transitioning to an open wave, which should facilitate its quicker transition eastward today. Stratus continues to erode in the east today as the first low becomes embedded in the flow, partly cloudy skies are expected west with highs in the low-mid 70s across the forecast area. This low level baroclinic setup may provide the impetus for showers in our south Wednesday and Wednesday night.
Much warmer conditions are expected late this week with summer-like temperatures likely by the weekend. Ceilings at TAF sites generally remain in the low end of VFR range but may briefly fall to MVFR as lower level moisture further increases overnight before drying moves in from the west. /ISSUED 548 PM MDT Mon May 25 2020/ Upper level ridge continues over the area through this evening prior to flattening with the approach of the next trough tracking north of the area. Windy conditions continue through Tuesday under under a moderate westerly flow aloft with low pressure continuing east across the Canadian prairies at the surface.
355 AM EDT Tue May 26 2020 High pressure will maintain generally dry and warm weather through Wednesday.
240 AM CDT Tue May 26 2020 An area of low pressure continues to lift to the north this morning accompanied by scattered showers and thunderstorms. Meanwhile, temperatures will remain a bit cooler in the middle to upper 70s for today. By Wednesday, the upper level low will begin to slowly migrate eastward across the Mississippi Valley region.
Otherwise, the story remains largely the same, H500 trough will become cutoff to the SW of the area. The airmass across the area remains primed for heavy rainfall development ahead of an approaching cold front, PWAT values will be in the 1.
325 AM CDT Tue May 26 2020 A cut off upper level low pressure system will develop over the Southern Plains today.
High pressure will remain in place across the region through the week. A northerly flow aloft is in place over Utah this evening downstream of a ridge building into the western Great Basin. A subtle disturbance riding over the top of the ridge has resulted in high clouds spreading into mainly northern and portions of central Utah this evening. The upstream ridge will remain in place over the next few days, although a series of weak disturbances will continue to flatten it through Wednesday.
High pressure will continue to dominate the weather through the rest of the week bringing above normal temperatures for the end of May. Some relief from the ridge will be possible by the weekend along with chances for dry thunderstorms. Mostly clear skies will continue overnight with near to slightly cooler than average overnight lows. A ridge of high pressure continues to build in over the desert southwest bringing warming temperatures and quiet weather. An area of low pressure will shift from over the Pacific into the longwave pattern and cause the ridge to shift eastward with temperatures cooling a few degrees to more around 5 to 10 degrees above normal.
This will result in high temperatures 5 to 10 degrees warmer than yesterday. This will send a cold front, south east of the Continental Divide Wednesday. This will result in cooler temperatures by 5-10 degrees east, but areas over the west and south should see similar temperatures as what occurs today.
Upper level trough extended from northwest ND to New Mexico. North end of upper trough will shear off and move into southeast MAN by 18Z Tue. East of upper trough, moisture continues to move northward into northwest MN. Upper level trough and FGEN will provide the forcing. An upper low continues working across the Central Plains this afternoon, which will influence our weather heading into tonight, mainly for portions of west-central Minnesota. Forcing is being provided by an upper trough that is becoming increasingly cut off as we head into the evening.
Much warmer weather will begin building into New Mexico starting today as strong high pressure takes hold of the region.
415 AM CDT Tue May 26 2020 (Today and Tonight) Upper level low will be centered over Oklahoma through tonight, with West Central Texas in west to northwest flow aloft.
A cold front will push through tonight and early Tuesday and turn low level winds east to northeast. Temperatures should be a little cooler behind the front in east winds.
230 AM PDT Tue May 26 2020 High pressure will continue to build over the region resulting in hot weather.
Afternoon showers are also expected, though will primarily occur over the higher terrain.
626 AM CDT Tue May 26 2020 (Today and tonight) With the continued shift of the upper level cyclone eastward, precipitation chances continue to shift with it.
However, with lingering moisture with clearing skies and temperatures warming into the low to mid 80s may contribute to a few isolated showers or possible thunderstorms. A weak impulse from the mid-level trough may trigger a few showers/thunderstorms across the northern zones but again, best forcing looks to be well north of the area and activity should be brief. Onshore flow will return through Wednesday as an area of low pressure develops across western Texas. Warmer temperatures in store for Wednesday with highs in the low to mid 90s for most locations, with mid to upper 80s along the coast.
Upper level low pressure trough just east but may impact the area with isolated light showers or possibly a thundershower later today. /issued 333 AM CDT Tue May 26 2020/ Weak upper level low pressure system will slowly edge just east of the area for the coming 24 hours. After a chilly start this morning, temperatures will climb into the high 70s or low 80s, slightly below normal. Any showers should dissipate quickly by early this evening with another cool and dry night expected just on the back side of the weak upper low. The upper low will be to our east by tomorrow morning.
Temperatures will continue to rise through the week as unseasonably strong ridge of high pressure moves overhead.
By this afternoon, the right exit region of an upper level jet will move into the Upper Midwest as an area of low pressure over the central Great Plains begins moving towards the Great Lakes region. A cold front will help push the rain east of the region by Wednesday afternoon.
417 AM CDT Tue May 26 2020 Today through tonight: An upper low closing off over the Southern Plains will shift slowly eastward toward the ArkLaMiss region in the near term while a strong upper level ridge builds along the East Coast.
Latest RAP analysis continues to show a trough axis bisecting central Florida, but as it lifts north through today, southwest winds aloft will advect some of this drier air into east central Florida. Overnight lows near or just slightly above normal for this time of year in the low 70s MVFR and even some IFR stratus will continue to lift through this morning with VFR conditions returning by late morning lasting into this evening (outside of convection).
Scattered showers and thunderstorms are possible again this afternoon thanks to a weak diffuse cold front moving across our area. Rain coverage should drop off somewhat this weekend as the upper level low ejects into the Ohio River Valley.
Mostly thin high clouds are over the region, with some low clouds moving into the coastal valleys, this morning behind a weak trough that brought very light showers to the northern fringes of the forecast areas earlier last evening. A flattened, broad upper ridge sits over the west coast, amplifying into Wednesday with a thermal trough deepening on the southern Oregon coast.
An upper level trough will move through Montana pushing a cold front through central Wyoming into central South Dakota. Temperatures are expected to be the upper 70s to low 80s, which is trending slightly toward the warmer side of the MAV and MET guidance. This cold front will move through western Nebraska overnight. The highest POPS, near 40 percent, will be west of a line from Valentine through Oshkosh with a slight chance as far southeast as North Platte through Butte.
/issued 350 AM CDT Tue May 26 2020/ An upper level trough is over the central part of the country.
That forcing will come late tonight and Wednesday morning when latest hi-res models show a weak Pacific trough coming in.
An area of low pressure continues to lift to the north this morning accompanied by scattered showers and thunderstorms. Meanwhile, temperatures will remain a bit cooler in the middle to upper 70s for today. By Wednesday, the upper level low will begin to slowly migrate eastward across the Mississippi Valley region.
A large upper-level closed low will develop across the central/southern Plains by midweek while west to southwest flow persists north of our region, bringing minimal precipitation chances. Have included high temperatures near the 50th percentile of climatology to have temperatures in the mid 70s east of I-29 and in the lower 80s west of I-29. Broad upper level ridging across the western CONUS begins to move eastward towards the end of the week. A gradual warm up is expected during the weekend and into the upcoming week as the upper-ridge axis move overhead, bringing west-southwest flow into the region.
927 AM EDT Tue May 26 2020 Weak area of low pressure off the east coast of the Florida peninsula will continue to lift slowly north today and tonight.
749 AM EDT Tue May 26 2020 High pressure will maintain generally dry and warm weather through Wednesday.
high clouds will be over the area for much of the period on the backside of an upper level low pressure area drifting slowly southeast into Oklahoma. we will be watching the far eastern portions of the forecast area during the afternoon and early evening hours for the possibility of some light rain showers as some moisture in the 850-500mb layer moves in from the east and northeast around the upper low which is expected to drift northeast into northeast Oklahoma. Another batch of mainly mid level moisture moves toward the CO/KS border during the evening/overnight hours providing a small chance for light rain showers as a cold front moves through. Low temperatures are expected to be in the low 50s.
A large upper-level closed low will develop across the central/southern Plains by midweek while west to southwest flow persists north of our region, bringing minimal precipitation chances. Have included high temperatures near the 50th percentile of climatology to have temperatures in the mid 70s east of I-29 and in the lower 80s west of I-29. Broad upper level ridging across the western CONUS begins to move eastward towards the end of the week. A gradual warm up is expected during the weekend and into the upcoming week as the upper-ridge axis move overhead, bringing west-southwest flow into the region. The lower ceilings and showers will move eastwards in the morning, possibly becoming isolated thunderstorms in south- central MN & north-central IA in the afternoon.
/EC/ Today through tonight: An upper low closing off over the Southern Plains will shift slowly eastward toward the ArkLaMiss region in the near term while a strong upper level ridge builds along the East Coast.
327 AM MDT Tue May 26 2020 High pressure will remain in place across the region through the week.
/issued 415 AM CDT Tue May 26 2020/ (Today and Tonight) Upper level low will be centered over Oklahoma through tonight, with West Central Texas in west to northwest flow aloft.
538 AM MDT Tue May 26 2020 Satellite imagery shows mid to high clouds streaming over a high pressure system building over the desert Southwest. Otherwise, warm airmass advecting into the region will result in high temperatures climbing 5 to 10 degrees warmer this afternoon. A shallow trough will cross the northern Rockies Wednesday as a low pressure system swoops across southern Canada. Moisture carried along the trough axis will dip into the northern tier of the CWA Wednesday afternoon. The trough axis crosses just north of the region during peak heating, which may support the development of isolated thunderstorms across northwest Colorado and boost storm initiation over higher terrain across the western slope. Storms will dissipate shortly after sunset as the trough axis quickly exits to the east and the lack of diurnal heating weakens lapse rates.
652 AM EDT Tue May 26 2020 High pressure will maintain generally dry and warm weather through Wednesday.
355 AM MDT Tue May 26 2020 An upper ridge will be building over the area today and will remain over the area tonight. Dry weather is expected across the area today and tonight and temps will be warmer than yesterday in most locations. Overall, confidence is on the higher side, with the main differences in the finer details.
/issued 325 AM CDT Tue May 26 2020/ A cut off upper level low pressure system will develop over the Southern Plains today.
An upper level cut-off low will develop later today in northern TX in the base of the upper level trough over the Plains. The deterministic and ensemble model guidance are fairly consistent that this upper low will move slowly east-northeastward into eastern OK on Wednesday. More convection is expected on Wednesday as low level moisture continues to advect northward into our area ahead of the low with the highest QPF likely across southeast MO and southwest IL. High temperatures will be slightly cooler on Wednesday due to slightly lower upper level heights, and with low level cloud cover inhibiting diurnal solar insolation.
Majority of the ongoing showers had also lifted into Kansas and Missouri with some light to moderate rainfall still occurring on the north and east side of the low. Additional shower and thunderstorm development will also be possible this afternoon into tonight as the upper low settles into the region and stalls. temps today look to warm into the low/mid 70s for most locations.
456 AM MDT Tue May 26 2020 Satellite imagery shows mid to high clouds streaming over a high pressure system building over the desert Southwest. Otherwise, warm airmass advecting into the region will result in high temperatures climbing 5 to 10 degrees warmer this afternoon. A shallow trough will cross the northern Rockies Wednesday as a low pressure system swoops across southern Canada. Moisture carried along the trough axis will dip into the northern tier of the CWA Wednesday afternoon. The trough axis crosses just north of the region during peak heating, which may support the development of isolated thunderstorms across northwest Colorado and boost storm initiation over higher terrain across the western slope. Storms will dissipate shortly after sunset as the trough axis quickly exits to the east and the lack of diurnal heating weakens lapse rates.
Otherwise, high pressure will dominate the weather across the Great Basin Region with warming temperatures through the next several days. Otherwise, dry conditions with a steady west wind developing during the day is expected across most of Nevada as high pressure builds over the Desert Southwest.
Isolated to sct convection will remain possible by mid and late afternoon across the area, but have curtailed VCTS mention and added VCSH mention for a few hours at SHV/TXK only as a spoke of energy aloft lifts NE ahead of a developing closed low over NW TX/Wrn OK. /This Afternoon/ Much drier air has entrained E into the region early this morning ahead of the closing upper low over NW TX/Wrn OK, with the 12Z KSHV raob depicting PW's of 1. The short term progs are in good agreement this morning with the developing closed low to our W drifting E along the Red River Valley of Cntrl/Srn OK/N TX through the afternoon, with additional drier air to the E of the low's center over ECntrl TX entraining E across much of the region today.
(This evening through Wednesday) Broad cut off upper low over the region will drift eastward.
126 PM MDT Tue May 26 2020 Strong upper jet coming into western Canada is expected to carve out a closed low over south-central Canada Wednesday that will put northeast Montana under a slight NW flow.
Much of the high res guidance has come in drier today with not much rainfall showing up at all, but then the NSSF CAMs do show another round of convection popping up mainly over the wrn 1/2 of the area by late afternoon. Scattered showers and thunderstorms are possible again this afternoon thanks to a weak diffuse cold front moving across our area. Rain coverage should drop off somewhat this weekend as the upper level low ejects into the Ohio River Valley.
Showers and storms are expected again tomorrow as an upper level low nudges in closer from the west. Best chances for showers and storms will be west of the I-65 corridor closer to the upper level low. Our unsettled weather pattern continues through the rest of the work week as the mid-level cut-off low located over ARKLATEX drifts slowly eastward before being absorbed by a the northern mid-level flow and trough across the Great Lakes.
A westerly flow pattern setting up behind an exiting trough today and Wednesday will allow for conditions to warm back to normal (low to mid 70s) for this time of the year.
Otherwise, conditions will be dry tonight, with overnight lows slightly cooler than usual late May lows. Models indicate the upper low will continue to slowly shift farther east.