Aikyam-Lab/Synoptic-Bench huggingface dataset:
This afternoon, a low-pressure system will track towards the Ohio River Valley is bringing moisture and a band of light rain to southwestern parts of the Northland. Meanwhile, high pressure over Hudson Bay is pushing drier air into the northern Great Lakes. As the low-pressure system continues its eastward trek this evening, an intensifying low-level jet will help expand the band of light rainfall northward and eastward across more of the Northland and northwestern Wisconsin. Looking ahead, this low will move eastward, while another low retrogrades across southeast Canada, reinforcing drier and slightly cooler air, particularly in the Arrowhead.
Lows Wednesday night will fall into the low 60s inland to upper 60s along the coast.
158 PM MDT Tue May 20 2025 - Warmer and drier for the rest of the work week.
This will lead to our next chance for showers and storms across much of South Texas tomorrow afternoon into the overnight hours, particularly as convection develops over the high terrain in Mexico and drifts east.
We're seeing lingering showers this morning on the backside of an exiting upper trough. There's still enough dynamic support and elevated instability for a few cells in the lower Snake Plain and a thunderstorm threat in the mtns.
(This evening through Wednesday night) "Cold" front currently extends from low pressure centered over Iowa through MO, AR, and into eastern TX. As an upper level disturbance swings around the southern periphery of a larger scale trough, it will force the front southeastward through this evening. Even though it's a cold front, temperatures will still be warmer than normal in its wake.
215 PM EDT Tue May 20 2025 A warm front will near from the west late this evening, bringing showers and storms that will linger into Wednesday. After that, an upper trough builds south into the area, and keeps rain chances elevated through Tuesday.
- Cooler and drier weather returns over the next couple days. (The rest of today ) Cold front is just clearing the far portions of the local forecast area across northwest AR into extreme SE OK.
Warm front extending southeast into central IL and southwest IN from low pressure in IA this afternoon. This stratiform rain already beginning to become more showery as the aforementioned boundary lifts north and becomes occluded with low pressure tracking east along it late tonight into Wednesday. Best chances for storms in the cooler air northeast of the boundary will be in our southwest zones (south of US 30 and west of IN-15 in IN) late this afternoon into this evening. Low-mid level trough axis then elongates from the lower Great Lakes to the Upper Midwest later tonight through Wednesday night. This will be due to troughing and a suppressed height field lingering in wake of a large merged upper low pinwheeling around the eastern Great lakes and New England.
1155 AM MDT Tue May 20 2025 - Warmer and drier for the rest of the work week. The lower 30s forecast for the Palmer Divide warrants a Frost Advisory there from 3-8 am Tuesday. The rest of the work week will then feature mainly dry and warmer weather, although a few opportunities will still exist for a few showers. It will still be breezy and almost exclusively dry for Wednesday due to downslope flow and slight ridging aloft.
However, a stout layer of mid-level dry air will likely be present that could limit ascent through entrainment, and coupled with the parent trough lifting rapidly to the NE, storms may struggle to initiate due to the limited forcing. High temperatures on Wednesday are a little tricky, as they are dependent on both how much the morning cloud layer can burn out and the timing of the front, but generally should be in the high 80s in the NW portions of the CWA and low 90s in the SE portions.
323 PM CDT Tue May 20 2025 Through tonight: The scenario continues to unfold as expected with a capped warm sector that is heating up strongly well ahead of an approaching cold front.
Issued 135 PM CDT Tue May 20 2025 Tonight through Wednesday night: Low pressure will continue to approach from the southwest this afternoon and evening, slowly sliding by just to the south of Wisconsin tonight into Wednesday. Meanwhile, showers will move in from the southwest this afternoon, with periods of showers likely though Wednesday as the low lingers in the region. Overall forcing will be less tonight into Wed as well, though the lingering moisture and some mid-level frontogenesis should keep the showers going with the low nearby.
- Cooler temperatures for mid to late week with drier conditions. The low-level shear is not that impressive, so the threat of strong tornadoes is mainly south of the area.
1141 AM MDT Tue May 20 2025 - Cooler temperatures, scattered showers and gusty winds expected through Wednesday. The CWA will be stuck in northwest flow Tuesday on the backside of the upper-level trough.
- A cold front will move through overnight into tomorrow morning that will bring a chance for rain along with the cooler nights and less humid days through the later half of the week.
124 PM EDT Tue May 20 2025 Low pressure south of Nova Scotia will move east today as high pressure begins to push down from the north. High pressure will remain to our north tonight into Wednesday.
Cooler and breezy conditions are expected Wednesday. As of 300PM ET a nearly stationary warm front remains draped across central and eastern KY as cold front approaches the Mid-Mississippi river valley. On-going convection aided by an outflow boundary, 1000- 15000 J/kg MLCAPE, and 50kts EBShear, has warranted a tornado watch for Scott/Morgan counties northeast into southwest Virginia through 8PM ET in closer proximity of enhanced moisture convergence and low- level shear on southern side of the aforementioned warm front. Additional convection is expected to develop later this evening into the early overnight hours along and ahead of the cold front. Some of the higher resolution guidance has started to hint at more pronounced bowing segments along and south of I-40 where the environment will be less tainted. Breezy winds and cooler conditions will develop in a post frontal air mass Wednesday.
It's a real soaker out there today as we find ourselves sandwiched between a low pressure over Iowa and a Hudson High. This baroclinic zone aloft will be affiliated with an inverted trough at the surface and these two forcing features are expected to budge north slightly tonight, then slowly slide back south through the day on Wednesday.
- By the end of the week, we will have high temperatures in the mid to upper 90's in the lowlands, with El Paso possibly seeing its first triple digit day.
(This evening through Wednesday Night) Convection begins to light up as of the 19Z hour, ahead of a northeast to southwest oriented cold front which is poised just on the western border of the ArkLaTex this afternoon. The highest probability exists for large hail as the hazard associated with these storms, but damaging wind gusts and an isolated tornado or two cannot be ruled out. Driven by the advancing cold front, convection looks to move eastward out of the area fairly swiftly, coming to an end for our southeasternmost Louisiana parishes by late this evening.
A secondary vorticity lobe is rotating around the southern periphery of the upper level low.
Low pressure to our south and a Hudson High well to our north will continue to be the main influences on the precipitation trends across our area through the next 24 hours as showers continue. Several quick-hitting rounds of precip will be possible within transient upper troughing regime, although shower activity remains low confidence.
Through the middle of this week, the upper-level flow pattern becomes less active and more calm, with some subtle high pressure ridging setting up from the south.
624 PM CDT Tue May 20 2025 - Cooler and dry weather tonight and tomorrow.
708 PM CDT Tue May 20 2025 (This evening through Wednesday Night) Convection begins to light up as of the 19Z hour, ahead of a northeast to southwest oriented cold front which is poised just on the western border of the ArkLaTex this afternoon. The highest probability exists for large hail as the hazard associated with these storms, but damaging wind gusts and an isolated tornado or two cannot be ruled out. Driven by the advancing cold front, convection looks to move eastward out of the area fairly swiftly, coming to an end for our southeasternmost Louisiana parishes by late this evening.
(Rest of tonight and Wednesday) Supercell and multicell clusters continue to move across north central and NE AL ahead of a cold front forecast to move through the TN Valley early Wednesday morning. In the wake of the intense system, mild conditions will prevail on Wednesday with mostly clear skies, temps in the low 80s, and breezy NE winds.
/EC/ Through tonight: The scenario continues to unfold as expected with a capped warm sector that is heating up strongly well ahead of an approaching cold front.
800 PM EDT Tue May 20 2025 A cold front will push offshore Wednesday afternoon into Wednesday evening, followed by high pressure through the weekend. Winds will be picking up as the surface pressure gradient increases ahead of an approaching cold front. Wednesday: A broken line of showers/tstms ahead of an approaching cold front will be in a weakening phase as it approaches the far interior areas prior to daybreak. Highs will warm into the lower-mid 90s, a bit cooler at the beaches where a pinned sea breeze will be late to form.
806 PM MDT Tue May 20 2025 - Warmer and drier for the rest of the work week.
Wednesday will be mostly dry as we continue the warming trend under an upper level ridge.
708 PM CDT Tue May 20 2025 Through tonight: The scenario continues to unfold as expected with a capped warm sector that is heating up strongly well ahead of an approaching cold front.
700 PM CDT Tue May 20 2025 - Shower chances of 20 to 50 percent continue tonight through Wednesday with the highest chances north of I-90.
Deep layered ridging continues its hold on Keys weather this evening. Upper level ridging spans the Gulf while the lower to mid level ridge straddles the Florida Peninsula. At the surface, the western flank of the Atlantic ridge stretches across the Bahamas and South Florida. Deep layered ridging will remain in control of our weather through the overnight. The western flank of an Atlantic ridge will remain across the Bahamas and South Florida overnight.
High pressure ridging across southern Florida will remain the dominant weather feature with slight seas and light west-southwest winds through Wednesday.
645 PM CDT Tue May 20 2025 (This evening through Wednesday night) "Cold" front currently extends from low pressure centered over Iowa through MO, AR, and into eastern TX. As an upper level disturbance swings around the southern periphery of a larger scale trough, it will force the front southeastward through this evening. Even though it's a cold front, temperatures will still be warmer than normal in its wake.
At the surface, a weak front will move eastward down the High Plains into western Oklahoma by the afternoon. The combination of compressional warming and a low- level thermal ridge impinging across the area will combine to promote a warm afternoon (upper-80s/low-90s).
(Today through Thursday) A weak frontal boundary stalled across northern ranchlands early this morning will move northward as a warm front later this morning. Otherwise, increase cloud cover should keep temperatures slightly lower today (near normal) with highs in the low to mid 90s, except for the 80s at the beaches.
1210 AM CDT Wed May 21 2025 - Cooler and dry weather tonight and tomorrow.
1200 AM CDT Wed May 21 2025 (Rest of tonight and Wednesday) Supercell and multicell clusters continue to move across north central and NE AL ahead of a cold front forecast to move through the TN Valley early Wednesday morning. In the wake of the intense system, mild conditions will prevail on Wednesday with mostly clear skies, temps in the low 80s, and breezy NE winds.
Sheppard Issued 135 PM CDT Tue May 20 2025 Tonight through Wednesday night: Low pressure will continue to approach from the southwest this afternoon and evening, slowly sliding by just to the south of Wisconsin tonight into Wednesday. Meanwhile, showers will move in from the southwest this afternoon, with periods of showers likely though Wednesday as the low lingers in the region. Overall forcing will be less tonight into Wed as well, though the lingering moisture and some mid-level frontogenesis should keep the showers going with the low nearby.
A cold front will drop S/SW this evening. and a warm front attempts to lift north. More aggressive NW flow will allow the cold front to gain SWD momentum. This break in the precip will be short-lived once again as a new warm front lifts back north over much of the state. Cooler and less active conditions will then be seen by the end of the forecast as a new front pushes SE through the region.
Through Thursday: Cloudy, cool, and generally dreary conditions will occur into Thursday as our region remains under the general influence of broad troughing with numerous perturbations slated to drift overhead.
Low pressure to our south and a Hudson High well to our north will continue to be the main influences on the precipitation trends across our area through the next 24 hours as showers continue.
Clearer and drier today behind the cold front. Discussion: Convection has moved east of the region this morning with the actual cold front still to our west across Middle Tennessee. Colder weather late week with troughing across the Appalachians.
(Today and tonight) Conditions are warmer and drier than they were this time last night, but only in the higher terrain. Elevated fire weather conditions will continue through tomorrow for the Interior Bay Area and Central Coast as dry conditions (poor daytime relative humidity of 15-25%, overnight relative humidity recovery of 30-50% in the higher terrain) and moderate to strong onshore winds continue.
Ensembles suggest the light rain is most likely to arrive Wednesday evening into Wednesday night with some light precipitation chances lingering into Thursday across mainly the higher terrain.
If anything, storms will likely slowly fall apart as they approach the coast and the influences of a large upper ridge over the southern Gulf. Once the surface cold front moves through the area, winds will quickly shift northerly and things will dry out once again. However, high temperatures on Thursday should still remain in the low 90s as drier low levels will allow for good afternoon warming.
(Today and tonight) A cold front will move across the area today with scattered to numerous showers and thunderstorms out ahead of it.
Areas of frost and some freezing temperatures possible Thursday morning.
Highs in the upper 90s to the lower 100s are forecast for the Memorial Day weekend.
238 AM EDT Wed May 21 2025 Scattered showers and thunderstorms remain possible through early this morning ahead of a cold front approaching from the west. Behind the front, we will see dry weather and cooler temperatures than we have experienced in the past week or so.
- Cooler temperatures for mid to late week with drier conditions. Broad troughing has become established across the north central US this morning and will continue through the day.
Low pressure moving through the northern Rockies will trigger some isolated thunderstorms during the evening, along with light showers throughout the night. It should be a dry and warmer day, with the next low reaching the western zones just at the end of this period. These won't be overly impactful but will serve to keep some cloud cover around and likely spark some diurnal shower/storm chances across the higher terrain along the Montana Divide and into the eastern highlands. Seems most of the precip would stay out of the lower elevations of the Snake Plain / Magic Valley but a stray shower or storm certainly can't be ruled out.
The remainder of the state will see mostly dry and warming conditions as a ridge starts to dry building in over the region. These drier and warmer conditions may create near elevated fire weather conditions in parts of the state today.
1154 PM CDT Tue May 20 2025 (This evening through Wednesday night) "Cold" front currently extends from low pressure centered over Iowa through MO, AR, and into eastern TX. As an upper level disturbance swings around the southern periphery of a larger scale trough, it will force the front southeastward through this evening. Even though it's a cold front, temperatures will still be warmer than normal in its wake.
Model guidance indicates these storms making it across the Rio Grande; however, weak winds in the lower levels will limit the chances for organized storms over South Texas. Chances for rain will diminish through Thursday with an upper-level ridge helping to keep chances low (5-15%).
1059 PM CDT Tue May 20 2025 - Shower chances of 20 to 50 percent continue tonight through Wednesday with the highest chances north of I-90.
1255 AM MDT Wed May 21 2025 - Warmer and drier for the rest of the work week. Thursday will be even warmer as the thermal ridge shifts closer to the forecast area, with highs closer to 80F across the plains.
Today's highs range from the lower 90s across the Hill Country to upper 90s along the Rio Grande. After a "cooler" 24 hour period, Thursday's highs are forecasted to range from the mid to upper 90s across most areas with 100 to 102 for the Rio Grande.
Elsewhere cooler than normal temperatures with light breezes will be the forecast.
Given the low confidence in storm placement I kept POPs around 20% mainly in north central through central Kansas this afternoon for a few pop up storms that should produce only light rain amounts. we should see a strong cold front for May standards pass through western Kansas during the evening and be south of the Kansas-Oklahoma border by Thursday morning. Thursday we should see mild and slightly cooler highs in the upper 70s. The upcoming holiday weekend continues to show an active weather pattern with the highest probabilities of QPF in central Kansas and lower probabilities as you move west.
1242 AM EDT Wed May 21 2025 High pressure will cross the region overnight through early Thursday, then exit to the east.
Remaining cool as well; highs in the low-60s are some ten degrees below normal.
Lows tonight will be seasonable as temperatures dip into the upper 50s across our northern zones to the lower and mid 60s elsewhere. On Thursday, upper-level ridge will begin to build into the southwest CONUS while troughing remains in place across the eastern CONUS. Meanwhile at the surface, a warm front will be lifting northward through our area.
(Today through Thursday) Cold front currently bisecting the area this morning.
This trend will continue as the upper level low tracks to the east across the southern Great Lakes this morning. Copious amounts of moisture cycling around the low will keep the region cloudy, cool and wet today into tomorrow. Cooler, more stable air will remain over the region as the low moves through so while there will be showers, not expecting storms. Once the low moves to the east a drier gradient will set up over the region. Michigan will be still dominated by that air mass with northwesterly flow on the back side of the exiting upper level low. The upper level low will finally move into far northeastern Canada the end of the weekend. - Cold the rest of the week with warming this weekend As stated above the upper level low will dominate the pattern through this weekend.
Most areas have warmed into the low 90s. However, the cap should break as the low levels continue to warm. Afternoon temperatures are expected to be in the low/mid 90s.
Last evening sounding did show a decent uptick in PWat values but the persistent deep layer ridge in place continues to provide stout subsidence.
Cooler and showery conditions will remain across the region through much of the week as a series of disturbances cross the region. High pressure likely rebuilds over the western U. over the weekend, bringing a return of warmer and drier conditions to the area.
445 AM EDT Wed May 21 2025 Low pressure tracking across the area today will bring scattered showers and a chance of thunderstorms. A large upper level low over the Great Lakes will keep cool and unsettled conditions in the forecast for Thursday.
651 AM EDT Wed May 21 2025 Scattered showers and thunderstorms remain possible through early this morning ahead of a cold front approaching from the west. Behind the front, we will see dry weather and cooler temperatures than we have experienced in the past week or so.
Upper ridging will build in today as an upper trough develops near 140W. This will result in dry weather with warmer afternoon temperatures compared to yesterday for the interior. A weak upper trough will move in Wednesday night into early Thursday morning and could bring a few showers over the northern part of the forecast area. The upper trough will move east Thursday morning with weak ridging building into the area.
958 AM CDT Wed May 21 2025 - Light rain today will give way to warmer weather by the weekend, but critical fire weather is not anticipated.
1054 AM EDT Wed May 21 2025 A cold front is located across eastern KY and the Cumberland Plateau. Clearer and drier today behind the cold front. Discussion: Convection has moved east of the region this morning with the actual cold front still to our west across Middle Tennessee. Colder weather late week with troughing across the Appalachians.
1036 AM EDT Wed May 21 2025 Cool and dry high pressure will be in control of our weather for the second half of the week.
Issued by National Weather Service Billings MT 321 AM MDT Wed May 21 2025 KEY MESSAGES: - A low pressure system will continue to bring rain showers to the eastern portion of the area, and a chance of thunderstorms in central Montana. WEATHER PATTERN OVERVIEW: A slow moving low pressure system will continue to impact the area through tonight before exiting eastward. A quick moving low pressure system will move in on Thursday evening.
645 AM CDT Wed May 21 2025 (Today through Thursday) A weak frontal boundary stalled across northern ranchlands early this morning will move northward as a warm front later this morning. Otherwise, increase cloud cover should keep temperatures slightly lower today (near normal) with highs in the low to mid 90s, except for the 80s at the beaches.
Bands of light rain continue to move southeast to northwest across the Northland this morning, as an upper level closed low breaks off from the main trough and moves eastward through the Ohio River Valley. Dry air associated with high pressure over southeastern Canada will continue to sit over portions of the Northland today, and will help erode the light rainfall from east to west. However, the airmass is not quite as dry as yesterday (where Min RHs bottomed out in the low to mid teens) and gusty east winds this morning will be diminishing through the day. With winds less than 5mph and temperatures falling into the low to mid 30s, frost is possible late tonight through early Thursday morning.
High pressure will build over the area today, keeping conditions dry and increasingly mild, before shifting east Thursday as a rather weak storm system grazes northern Utah.
Otherwise, expect another rather hot day with inland areas climbing into the lower to middle 90s, while the coastal areas stay in the middle to upper 80s thanks to the westerly flow.
Cool and unsettled conditions will continue through Thursday under the influence of troughing.
537 AM MDT Wed May 21 2025 - Warmer and drier for the rest of the work week. Thursday will be even warmer as the thermal ridge shifts closer to the forecast area, with highs closer to 80F across the plains.