Aikyam-Lab/Synoptic-Bench huggingface dataset:
Ahead of the wave and associated cold front, near sfc-based destabilization is uncertain given lingering cloud cover and a stabilized boundary layer from the initial system. As we go through the overnight, a much drier and cooler air will surge into the forecast area behind the cold front.
Hi-res guidance develops scattered convection near 12Z across portions of the Edwards Plateau and Hill Country, with this activity drifting south through the morning hours today as the main cold front pushes through.
Will start off the morning in the lower 20s though so bundle the kids up for those early morning soccer matches.
Boxell (Issued 429 AM CDT Fri Apr 21 2023) Today through Saturday: The low will sit over northeast MN and Lake Superior today. Meanwhile, showers will be rotating around the low over MN, but they are expected to dry up as they reach south central and central WI. Precip chances return on Saturday as another lobe of the upper low swings through.
High pressure will remain centered off the coast of California. This will help to increase the winds and bring warmer valley temperatures. Some of the favored areas in the northeast foothills(along ridge by Jarbo Gap) are expected to get northeast wind gusts 25 to 30 mph in the morning.
Tonight and Tomorrow night will see sub- freezing and hard freeze temps.
1003 AM EDT Fri Apr 21 2023 High pressure will slowly lift away to the northeast Friday into Saturday.
Otherwise, high pressure offshore will continue promoting dry and warming trend into the weekend. HREF models indicates high level clouds spreading across the region later Saturday afternoon ahead of an approaching weak upper level trough to the Pacific Northwest.
640 AM CDT Fri Apr 21 2023 (Today and tonight) A rather pleasant day is expected across the area today, as light northerly winds and cooler temperatures prevail. Highs this afternoon will range from the low to mid 70s across the Big Country, to the upper 70s and lower 80s along the I-10 corridor.
322 AM MDT Fri Apr 21 2023 Water vapor imagery shows the center of the upper low has now moved out of the Dakotas and into western MN. On the backside of the low, northwest flow persists across the CWA. A strong wave has pinwheeled around the low, crossing western South Dakota over the last few hours. As the low pressure system slides eastward today, snow will gradually end from west to east across the CWA. Gusts to 45-55 mph are expected across much of the western SD plains, but a gradual decrease is expected through the afternoon into the early evening, as high pressure builds in from the west.
This along with a short wave trough will be the main lift contributors for today and tonight. Lapse rates of 6-7C/km combined with the moisture and the strong flow at and just above ridge top will lead to a good orographic snow set up.
441 AM MDT Fri Apr 21 2023 Water vapor imagery shows the center of the upper low has now moved out of the Dakotas and into western MN. On the backside of the low, northwest flow persists across the CWA. A strong wave has pinwheeled around the low, crossing western South Dakota over the last few hours. As the low pressure system slides eastward today, snow will gradually end from west to east across the CWA. Gusts to 45-55 mph are expected across much of the western SD plains, but a gradual decrease is expected through the afternoon into the early evening, as high pressure builds in from the west.
634 AM CDT Fri Apr 21 2023 (Today through Saturday Night ) H500 trough will continue to progress eastward across the area today. Sfc cold front will progress out of the state with some occasional rain/thunderstorms expected to develop and lift north across roughly the southeast half of the state today. Sfc ridging will build in from the northwest on Saturday which will provide some well below normal temperatures to the state along with dry conditions for a short time.
A warm front extends across the region this morning with ongoing precipitation focused along northern portions of the forecast area. The current warm front will weaken later this morning, but another trough will approach western Canada this afternoon, pushing another weaker warm front into the area. After a cloudy start Saturday morning, clouds will give way to sun with afternoon temperatures reaching into the low 70s west of the Cascades and low to mid 60s east of the Cascades.
429 AM CDT Fri Apr 21 2023 (Issued 429 AM CDT Fri Apr 21 2023) Today through Saturday: The low will sit over northeast MN and Lake Superior today. Meanwhile, showers will be rotating around the low over MN, but they are expected to dry up as they reach south central and central WI. Precip chances return on Saturday as another lobe of the upper low swings through.
The main factor in our sensible weather for the short term is an area of high pressure planted just of the coast of the Carolinas. This high will continue to slide east today promoting gentle easterly breezes. By tonight, a frontal boundary trailing behind this high will set up along the southeast US slotting the Keys into a col region resulting in large drop off in winds for Saturday. While shrinking PW values and rising heights were observed in yesterday evening's sounding, opted to keep slight rain chances through Saturday due to lingering moisture in the lower to mid levels making it impossible to rule out a stray shower or two. Lighter winds and warmer than normal highs on Saturday will also call into question cloudline and possible waterspout formations.
However, RH in the lowest 300mb is near 70 percent. So while overall conditions are unfavorable for convection, light winds and sufficient moisture in the lower boundary layer could lead to cloud lines developing along the islands with afternoon heating, especially in the Lower Keys. The current suite of MOS guidance all show chances of rain today in the low single digits. Outside of the possibility of cu-line development in the Lower Keys, there is no reason to disagree with guidance at this point.
635 AM EDT Fri Apr 21 2023 Dry high pressure and above normal temperatures will continue today. A cold front moves through the region tomorrow, bringing showers and a few thunderstorms along with it.
349 AM PDT Fri Apr 21 2023 Weak offshore flow will continue today with high pressure aloft off the West Coast.
As for temperatures, the window between the exiting MCS and arriving cold front could get a bit warm for the CWA. The combination of insolation/SW flow at the lower/mid levels could push highs into the lower to maybe even mid 80s for the central/coastal counties this afternoon. But by tonight, cooler/drier air will be filtering into the region as high pressure builds in briefly behind the front. With clearing skies and modest CAA/north winds, low temperatures tonight will be in the lower to mid 50s north. Sat night lows will run a couple of degrees warmer as the winds become more E/SE.
122 PM PDT Fri Apr 21 2023 Weak offshore flow will continue today with high pressure aloft over the West Coast.
227 PM EDT Fri Apr 21 2023 A deep low pressure system over the upper Mississippi Valley will push a cold front and associated showers and thunderstorms through the Mid Atlantic region on Saturday.
329 PM EDT Fri Apr 21 2023 High pressure will slowly lift away to the northeast tonight into Saturday.
This trough also supports a 10 to 20 percent chance of thunderstorm development through sunset tonight particularly further northeast around the Upper Snake Plain.
(This evening through Saturday) One last mild day was underway ahead of an unseasonably strong cold front poised to sweep through the region early Saturday morning. This low will migrate across the South Plains tonight in response to surface ridging plunging south. NBM looks too mild with highs across the board, so opted to blend in some of the lower CONSSHORT values for this pattern.
318 PM EDT Fri Apr 21 2023 A cold front will bring a period of unsettled weather to the region tonight and especially on Saturday.
(This evening through Saturday) There is potential for isolated thunderstorms to develop in a modified warm sector, ahead of a secondary cold front, late Saturday afternoon across mainly the Heartland and eastern 2/3 of the Concho Valley. Highs Saturday will range from the lower to mid 70s across the Northern Big Country to the mid 80s west of an Ballinger to Junction line.
Broad upper-level ridge over the Northern Pacific will dominate the Golden State's weather for the foreseeable future. Highs this afternoon will peak in the low 80s throughout much of the Sacramento and northern San Joaquin Valleys, equaTing to roughly 5 to 8 deg F above mid/late April climatology. Saturday will remain mostly clear and tranquil with highs in the low to mid-80s for the Valley.
239 PM CDT Fri Apr 21 2023 A trough of low pressure is swinging through the Great Plains and Upper Midwest into the Mid Mississippi Valley this afternoon. This trough is driving a cold front ahead of it through our area.
106 PM EDT Fri Apr 21 2023 High pressure will slowly lift away to the northeast Friday into Saturday.
A stacked closed low is still placed over northeast Minnesota this morning, with light snow persisting across parts of central and most of eastern North Dakota. Today's upper low begins to split on Saturday, although it does not move much, keeping northwest flow and cooler temperatures over the forecast area.
Overall it should be another cooler day with northwest winds and mid to high level clouds on the increase towards afternoon with an upper level short wave. For tonight a cold front will sweep across western Kansas changing the winds to the northeast and a brief period of stronger winds will occur with the frontal passage as the mixing should be greatest at that point. the stronger winds and cloud cover will lean towards keeping most of the areas above freezing that are susceptible climatologically for this time of year. Saturday should be cooler than today as highs will be in the 50s.
234 PM CDT Fri Apr 21 2023 Water vapor imagery currently shows an upper low moving into the Western Great Lakes region with strong northwest flow from the Northern Rockies through the Plains. At the surface, low pressure is stacked under the upper low over the Upper Mississippi Valley with northwest winds continuing to pump below normal temps into the region. This will provide subfreezing temps early Sat morning for areas generally along and north of I-70, with the remainder of the area in the mid 30s.
Temperatures were largely in the mid to upper 80s with some areas of the Upper Keys in the lower 80s. Much of the Florida Keys is entering into a col region as the high pressure that was producing the stronger east to southeast winds pulls further away into the Atlantic. The aforementioned high pressure moves even further into the North Atlantic tonight and through the weekend leaving the Florida Keys in the col region. However, the one caveat will be the amount of moisture present which seems to be an ongoing obstacle across the Island Chain, in particular, the Lower Keys through the winter and now into spring.
The upper level trough evident in satellite water vapor imagery over the Arrowhead of Minnesota. Tomorrow, the upper level trough farther east results in northwest flow and continual cold air advection. High pressure settling into the region will bring a break of any widespread accumulating precipitation chances for the start of the new work week. Northwesterly flow will dominate aloft as an upper level low holds over southern Ontario through mid week.
Overnight lows into the mid to upper 20s but with warm ground temperatures, don't suspect we'll see many issues with refreeze other than perhaps more elevated surfaces/bridges.
1214 PM CDT Fri Apr 21 2023 (Today and tonight) A rather pleasant day is expected across the area today, as light northerly winds and cooler temperatures prevail. Highs this afternoon will range from the low to mid 70s across the Big Country, to the upper 70s and lower 80s along the I-10 corridor.
221 PM EDT Fri Apr 21 2023 A cold front will move across the region tomorrow, bringing showers and a few thunderstorms along with it.
302 PM EDT Fri Apr 21 2023 A cold front will push southeast of the area tonight bringing widespread rainfall overnight. Cooler air moves in from the west for the weekend and the start of the workweek. A SW-NE oriented cold front is slowly progressing southeast through the area early this afternoon. Winds shift to the north overnight as the low pulls the front through. Cooler air works in behind the front by sunrise. A low pressure system continues to pull northeast of the Ohio Valley on Saturday. Much cooler air works in behind the low on westerly flow. Cool, westerly flow persists Saturday night thanks to the broad area of low pressure remaining northeast of the area. Cloud cover should diminish somewhat overnight with diurnal instability fading off, but some clouds remain with upper troughing in place.
High temperatures will only reach the upper 40s and lower 50s on Saturday while overnight lows dip into the lower to middle 30s. 20z/3pm surface analysis shows a weak trough axis between the Illinois River and I-55. With 700-500mb lapse rates of 6-7C/km and SBCAPEs of around 100J/kg, would not be surprised to see isolated showers develop further south along the trough over the next couple of hours. Deep upper low currently over northern Minnesota will track eastward over Lake Superior on Saturday. The turbulent mixing created by the wind will prevent frost formation and keep overnight lows above the freezing mark across much of the area. The exception may be west of the Illinois River where overnight lows are progged to dip into the lower 30s and where a Freeze Watch remains in place.
Issued by National Weather Service La Crosse WI 241 PM CDT Fri Apr 21 2023 An upper level low pressure system continues to spin across the Upper Midwest this afternoon. A stratus field was rotating towards the area on the southern periphery of the low with scattered rain/snow showers working southeast from northern and western Iowa beneath the cool air aloft. An unseasonably cool airmass will remain entrenched over the area into the weekend as the upper level trough stubbornly persists across the Great Lakes. Otherwise, with forecast low temps in the low 30s for western/northern counties, will convert the Freeze Watch to a Warning for tonight. However, by late week a cold front could approach with increasing rain chances, but models vary in the timing and strength of this system.
For those of you who may not know, a steam devil looks similar to a water spout or dust devil, but develops when cold air moves over a warmer wet surface. Today expect continued convective activity, that will translate into showers moderate to heavy at times of graupel or snow and the low chance for a strike of lighting or two.
229 PM MDT Fri Apr 21 2023 Scattered snow showers will diminish this evening, as an upper level ridge of high pressure tries to build into Western MT.
Warmer temps on Friday and into this weekend, highs 60s along the coast, upper 70s inland.
206 PM MDT Fri Apr 21 2023 Afternoon Discussion: As the upper level low that has brought the area with the broad area of light snow showers departs further to ECONUS, Montana is forecast to be under NW flow through the weekend.
309 PM EDT Fri Apr 21 2023 A cold front will bring a period of unsettled weather to the region tonight and especially on Saturday.
Saturday will be warmer with highs in the 70s north.
As daytime heating increases, SBCAPE is gradually increasing this morning, especially ahead of an approaching cold front through East Texas/North Louisiana/north-central Mississippi. Storms along the cold frontal boundary are beginning to look a little more organized at this hour, and with 40-60 kts of deep-layer shear across these storms, further intensification is expected heading into the afternoon. As the upper-level trough overspreads the area of greater instability this afternoon, additional storms are also expected to develop in the warm sector. Ahead of the wave and associated cold front, near sfc-based destabilization is uncertain given lingering cloud cover and a stabilized boundary layer from the initial system. As we go through the overnight, a much drier and cooler air will surge into the forecast area behind the cold front.
Low pressure still rotating out over the MN arrowhead continues to bring moisture to portions of our counties, but becoming less widespread as the day goes on. Quiet conditions will set in for Saturday and Saturday night as we get some high pressure building into the Northern Plains. Highs tomorrow will be mostly below freezing except in the MN trees, and lows will be in the teens Saturday night. Surface temperatures will be on the cooler side to start the period.
(Today through Saturday) Early this morning, a strong upper trough extended from the Upper Mississippi River Valley southward into Texas. At the surface, a cold front extended from northern Indiana, to near Texarkana, to central Texas. The actual cold front will move through the area this evening. Some potential for high temperatures to be warmer than currently forecast if we lose clouds early enough this afternoon.
High pressure will prevail across the greater region. For Saturday, a tranquil weather pattern is expected as high pressure continues to prevail across the greater region. Highs tomorrow should top out in the lower to mid 50s. Some minor good news with the cooler highs is that the fire danger will be low tomorrow and we can get a continued break from the fire danger.
A cold front is moving through South Central Texas and will provide a focus for strong weather, but will otherwise be fairly weak in terms of cooling things down or producing rain for the CWA over the next 24 to 36 hours. The weak cold front, now half-way through the Corpus Christi area with the tail end almost into Zapata County, should ooze through later tonight, reaching the coast as early as midnight, and weather chances will end except for isolated showers near the coast. That will set the stage for a calmer Saturday as high pressure builds across Texas. Skies will remain partly cloudy on Saturday and temps will drop a mere 5 degrees Fahrenheit or so, down from the lower to middle 90s today to the middle 80s to lower 90s Saturday.
Scattered showers will linger in the higher terrain this afternoon, with brief periods of MVFR/IFR conditions in showers.
(Rest of today through Saturday) High pressure in the Western Atlantic continues to weaken and push further out to sea, opening up an opportunity for the Gulf Breeze to return today. For Saturday, a cold front will be approaching the Florida Peninsula from the north as it detaches from a deep low over the Great Lakes region. This will lead to increased moisture return flow, at least in the low levels.
Rain will be ending this evening across the Mid-South as a cold front moves out of the region.
Behind the boundary, northerly winds will bring in a noticeably cooler and less humid airmass.
Showers and a few thunderstorms will cross the area overnight along a cold front, exiting Saturday morning. Cooler temperatures build in behind the front on Saturday. Discussion: The mild pattern that we have been experiencing over the past few days will come to an end tonight as a deep upper trough pushes a cold front through the area. However, the upper trough axis will still be crossing the area through the day, and cooling midlevel temperatures and steep low level lapse rates could genereast of our areaate some isolated to scattered showers, mainly in the northern half of the area. High temps will be in the 60s in most spots, with 50s in the higher elevations.
However, cyclonic flow associated with a mid and upper level low over the Upper Midwest, and an approaching PV anomaly, will result in an increase in mid and high clouds this afternoon into Saturday.
(This Evening and Tonight) Clouds have overspread the region this afternoon as a cold front and its associated showers (and a few storms) approach the area from the west. As the front shoves eastward late tonight into early Saturday morning, precipitation will taper off from west to east, with cooler air filtering in as lows will drop to the upper 40s to lower 50s.
5" look feasible with the higher amounts in the west where shower activity has been ongoing through the day so far. A reinforcing shot of cooler air will move into the area Saturday afternoon/evening with some models showing a slight chance of an isolated shower along the northern plateau Saturday afternoon.
1122 AM EDT Fri Apr 21 2023 Dry high pressure and above normal temperatures will continue today. A cold front moves through the region tomorrow, bringing showers and a few thunderstorms along with it.
Later this afternoon into tonight, the approaching cold front will sweep across the region potentially bringing another round of convection with it.
233 PM EDT Fri Apr 21 2023 Shower and thunderstorm chances will increase through the night with the approach and passage of a surface cold front. A surface cold front currently stalled across western Ohio will attempt to slowly track east through the overnight period, utilizing an advancing upper trough axis to regain its eastward movement. The rest of the region will generally remain dry under subsidence, with a light shower could develop over the higher terrain with some ridge top convergence. By the afternoon, shower activity will become more isolated with dry, cold advection occurring behind the front but continued jet ascent with the nearby positioning of the upper trough axis.
High pressure tracks to our east later in the day and winds above the surface will veer to the se/s and allow for some cloud cover to gradually return to the region as higher PW's are drawn in from the western Gulf.
With high pressure growing from the upper level ridge that has developed over the eastern Pacific, there is no wonder how temperatures are running seven to eight degrees warmer today. The ridge hangs over the area for another day, so residents can expect another warm day on Saturday with similar temperatures.
841 AM PDT Fri Apr 21 2023 Weak offshore flow will continue today with high pressure aloft off the West Coast.
300 PM MDT Fri Apr 21 2023 Current analysis shows stacked low pressure over far northeast MN. Conditions will continue to gradually improve late today into this evening as the low pressure system moves further away from the region.
Lows tonight are expected to fall into the low to mid 30s. The core of the upper level low that is currently located over northern Minnesota will rotate southward into the area tonight and tomorrow. The increased cloud cover and precipitation will keep temperatures cooler, with highs only expected to be in the low to mid 40s.
Key Messages: - Cold temperatures at or below freezing tonight, a freeze warning has been issued midnight through 9 am Saturday. - Freezing temperatures forecast for Saturday night.
1116 AM MDT Fri Apr 21 2023 Water vapor imagery shows the center of the upper low has now moved out of the Dakotas and into western MN. On the backside of the low, northwest flow persists across the CWA. A strong wave has pinwheeled around the low, crossing western South Dakota over the last few hours. As the low pressure system slides eastward today, snow will gradually end from west to east across the CWA. Gusts to 45-55 mph are expected across much of the western SD plains, but a gradual decrease is expected through the afternoon into the early evening, as high pressure builds in from the west.
Tonight a cooler airmass will work into the area. Minimum temps Saturday night fall into the low to mid 30s.
1227 PM CDT Fri Apr 21 2023 (Today through Saturday Night ) H500 trough will continue to progress eastward across the area today. Sfc cold front will progress out of the state with some occasional rain/thunderstorms expected to develop and lift north across roughly the southeast half of the state today. Sfc ridging will build in from the northwest on Saturday which will provide some well below normal temperatures to the state along with dry conditions for a short time.