Aikyam-Lab/Synoptic-Bench huggingface dataset:
There is zonal flow aloft over southeast Idaho with a very weak trough currently moving over northern Idaho. Further upstream, there is another slightly stronger trough just off the southern British Columbia coast. Tomorrow, Sunday, models show the trough currently off the southern British Columbia coast moving over central Idaho starting early morning and exiting our area by early to mid afternoon.
Sunny and mostly dry conditions should prevail for the remainder of the day across interior NorCal, except for a few isolated showers and possible t-storms over the high Sierra south of Highway 50.
1033 AM PDT Sat May 18 2024 Cooler and unsettled weather will continue through the weekend.
A boundary associated with a low pressure moving eastwards across the MS/AL line is enabling storm development and will continue through the late afternoon. On Sunday, drier conditions look to prevail as an upper trough ejects out of the Southeast region onto the eastern coast. Deep ridging will begin to build into the Lower Mississippi Valley, allowing for temperatures to increase and cloud cover to dissipate.
(This evening through Sunday) Hot and dry conditions will prevail across the area through Sunday as the area remains under short wave ridging aloft. Skies will be mainly clear through tomorrow, with overnight lows in the upper 60s tonight, with highs tomorrow afternoon similar to today, ranging from the low to mid 90s east, to the upper 90s to near 100 west.
1248 PM MDT Sat May 18 2024 - Warmer Sunday with thunderstorms. Water vapor shows upper low along the ND/Canadian border, flat ridge over the Northern Rockies, and upper low over southwest BC. Warm front will lift back into the area after midnight tonight, with 50kt low level jet and decent theta-e advection resulting in a few late night showers/storms in our eastern and northern SD zones. On Sunday, upper low currently over southwest BC will dig into the Northern Rockies, with southwest flow aloft through the Northern Plains and temps rebounding into the 70s to mid 80s behind passage of warm front. Cold front will work into far western during the afternoon, with MLCAPE of 1000-2000J/kg.
With 850 mb temperatures expected to climb to between 22-24C on both days, high temperatures will range from the low/mid 90s to near 100F both today and Sunday.
(This evening through Sunday) Tonight will bring mild and clear conditions as the upper-level ridge still remains over us. Into tomorrow, the upper- level ridge will move towards the east ahead of a broad upper-level trough located in the Pacific Northwest. While the northern extent of the Low should keep the precipitation outside of our CWA, a dryline will form extending all the way down to the Mexican border.
As the low tracks east winds will subside especially with the loss of heating around 7-9pm. Due to the high variation in surface pattern (frontal zone may not set up this far northeast) and storm coverage could remain more sparse.
Relatively light winds and dewpoints near 60 degrees are making it feel a bit warmer as well. Large hail and damaging winds will be the primary hazards, with a window for an isolated tornado as the low level jet strengthens during the early evening, especially if any isolated supercells can become established.
254 PM EDT Sat May 18 2024 Low pressure will drift off the Carolina Coast through the weekend.
1220 PM CDT Sat May 18 2024 (Today and tonight) High pressure will start to build across the region for this afternoon.
1115 AM MDT Sat May 18 2024 - Dry, cooler and breezy today. - Warmer Sunday with thunderstorms. Current surface map places cold front across eastern South Dakota into central Nebraska. Low level thermal ridge peaks Sunday afternoon, with highs in the 70s to lower 80s. Upper trough lingers across the Pacific Northwest/Northern Rockies through much of the coming week with a series of impulses crossing the area.
1130 AM CDT Sat May 18 2024 (Today through Sunday afternoon) Major changes begin today in the form of summer heat! Mid level ridging has quickly built in across the region as surface winds veer to the southwest. Deep mixing will send highs soaring nearly 20 degrees over yesterday and into the upper 90s to near 100 in the lower elevations. This will lead to increased fire weather conditions, especially across the higher terrain.
218 PM MDT Sat May 18 2024 KEY MESSAGES: - An oncoming surface cold front will move in overnight, bringing rain showers and thunderstorm probabilities that will last through Sunday evening. WEATHER PATTERN OVERVIEW: The cold front will move far enough east late this afternoon to allow breezy west winds to fall off this evening. Clouds will increase from the west ahead of the next cold front.
Water vapor imagery highlights a positively tilted mean- layer ridge centered over the Western Caribbean and the Bahamas. Temperatures are in the lower to mid 90s and dewpoints are touching 80. The oppressive heat will continue into Sunday with afternoon highs in the lower to mid 90s and heat indices climbing above 100.
High pressure will continue to build in this weekend with hot and dry conditions expected. Lows tonight will be in the upper 60s further north and in the low 70s for the rest of the area.
Breezy winds have developed due to a tightening pressure gradient ahead of an approaching trough and low-pressure center. Ensemble and deterministic models agree that the trough will move into north-central Idaho and western Montana tonight.
444 PM CDT Sat May 18 2024 (This afternoon through Sunday night) WV imagery shows an weak, upper-level ridge in place over West Texas and Southeast New Mexico this afternoon. Tonight, the ridge moves east of the area, courtesy of a PacNW trough digging southeast, putting the area under southwest flow aloft. Leeside troughing on the Front Range ahead of this feature will induce a 40+kt LLJ, keeping the boundary layer mixed, and overnight minimums ~ 6-8F above normal. Sunday, leeside troughing will increase surface winds across the area, adding a downslope warming component to the mix, and increasing thicknesses to provide the first day this spring of widespread triple-digits outside of the Rio Grande Valley.
(The rest of tonight) Upper ridging in place and high pressure just off to the east will allow for quiet conditions overnight.
742 PM EDT Sat May 18 2024 High pressure extending from the Labrador Sea and the Canadian maritimes back across our region will generally keep fair dry weather in place through at least the beginning of the new work week.
On the other hand, another round of showers and isolated thunderstorms is possible on Sunday as upper level disturbance ans associated cold front attempt to move across the Peninsula. There is lot of uncertainty with the timing, but at this time, the highest chances should be mid morning and into the afternoon.
500 PM MDT Sat May 18 2024 - Warmer Sunday with thunderstorms. Water vapor shows upper low along the ND/Canadian border, flat ridge over the Northern Rockies, and upper low over southwest BC. Warm front will lift back into the area after midnight tonight, with 50kt low level jet and decent theta-e advection resulting in a few late night showers/storms in our eastern and northern SD zones. On Sunday, upper low currently over southwest BC will dig into the Northern Rockies, with southwest flow aloft through the Northern Plains and temps rebounding into the 70s to mid 80s behind passage of warm front. Cold front will work into far western during the afternoon, with MLCAPE of 1000-2000J/kg.
These light showers were along a nearly diffuse cold front that will continue to sag south of Interstate 20 and near Highway 84 the remainder of tonight. A boundary associated with a low pressure moving eastwards across the MS/AL line is enabling storm development and will continue through the late afternoon. On Sunday, drier conditions look to prevail as an upper trough ejects out of the Southeast region onto the eastern coast. Deep ridging will begin to build into the Lower Mississippi Valley, allowing for temperatures to increase and cloud cover to dissipate.
514 PM EDT Sat May 18 2024 High pressure extending from the Labrador Sea and the Canadian maritimes back across our region will generally keep fair dry weather in place through at least the beginning of the new work week.
Cool and showery conditions will persist today with an upper level trough situated over the region. The trough will move east by Sunday afternoon allowing for upper level ridging to nudge into Western Washington.
630 PM CDT Sat May 18 2024 (This evening through Sunday) Hot and dry conditions will prevail across the area through Sunday as the area remains under short wave ridging aloft. Skies will be mainly clear through tomorrow, with overnight lows in the upper 60s tonight, with highs tomorrow afternoon similar to today, ranging from the low to mid 90s east, to the upper 90s to near 100 west.
838 PM MDT Sat May 18 2024 An upper level trough encompasses much of SW Canada extending into the NW US with somewhat moist and unstable westerly flow across the Northern Rockies and MT leading to the development of widely scattered showers earlier today. The next disturbance moving through the upper level trough will arrive in western MT later tonight with an area of more widespread precipitation developing over western portions of central MT early Sunday morning.
625 PM CDT Sat May 18 2024 (Tonight) A quiet night is on tap across eastern Oklahoma and western Arkansas as high pressure prevails at the surface and aloft.
931 PM EDT Sat May 18 2024 Low pressure will drift off the Carolina Coast through Sunday.
632 PM CDT Sat May 18 2024 (This evening through Sunday) Tonight will bring mild and clear conditions as the upper-level ridge still remains over us. Into tomorrow, the upper- level ridge will move towards the east ahead of a broad upper-level trough located in the Pacific Northwest. While the northern extent of the Low should keep the precipitation outside of our CWA, a dryline will form extending all the way down to the Mexican border.
618 PM CDT Sat May 18 2024 (This evening through Sunday Night) A field of fair weather cumulus clouds this afternoon will begin to quickly dissipate around sunset this evening as high pressure at the sfc continues to dominate. Another warm day will follow on Sunday as light SE flow returns in the wake of advancing high pressure. Temperatures will likely run a few degrees warmer on Sunday compared to today with mostly locations reaching into the lower 90s under a field of afternoon cumulus once again.
217 PM PDT Sat May 18 2024 A low pressure system will drop into the region and bring cooler temperatures, afternoon breezes and a 10-20% chance of showers through the upcoming week. Late Afternoon/Tonight: There remains a 20-35% chance of showers and thunderstorms mainly near and south of Bridgeport and Hawthorne through early evening with gusty outflows 30-40 mph, brief heavy rain, lightning and small hail. Increasing westerly flow and drying as evident in ridgetop winds and WV imagery will keep things stable for the rest of the Sierra and western NV through this evening.
Another dry cold front will move across the area late this evening, bringing brief gusts 30-40 mph with winds remaining breezy overnight. Cooler air behind the front will result in highs on Sunday 10-15 degrees cooler than today. Any significant chance (20-50%) of showers will be limited to the northern mountains of central Idaho and northeast Oregon, closer to the core of the upper level trough. Surface winds: NW 5-15 kt increasing to 10-20 kt with gusts 25- 40 kt tonight with a cold front. Winds NW 5-10 kt increasing to 10-15 kt with gusts 20-30 kt around Sun/05Z due to cold front.
(Tonight) Lingering convection from earlier this afternoon has just about diminished this Sat evening, as an upper trough axis begins to move east of the mid TN Valley. Overnight temps look to be fairly normal for this time of the yr, with early morning lows Sun mainly in the lower 60s/near 60F for most spots.
940 PM CDT Sat May 18 2024 Evening satellite imagery depicts the last wisps of cirrus wrapped around an upper low pressure system exiting into Middle TN. Expect a calm and benign evening otherwise with temperatures in the lower 60s.
1008 PM EDT Sat May 18 2024 High pressure extending from the Labrador Sea and the Canadian maritimes back across our region will generally keep fair dry weather in place through at least the beginning of the new work week.
Beyond that, the forecast remains unusually uncertain, due to a cold front forecast to drop into the area into Sunday. Overnight lows expected in the lower to mid-70s.
931 PM CDT Sat May 18 2024 Surface and upper-level ridge across the region to maintain stable conditions overnight. With mostly clear skies, temperatures are forecast to fall into the low to mid 60s. /05/ (This evening through Sunday Night) A field of fair weather cumulus clouds this afternoon will begin to quickly dissipate around sunset this evening as high pressure at the sfc continues to dominate. Another warm day will follow on Sunday as light SE flow returns in the wake of advancing high pressure. Temperatures will likely run a few degrees warmer on Sunday compared to today with mostly locations reaching into the lower 90s under a field of afternoon cumulus once again.
851 PM CDT Sat May 18 2024 Upper level troughing influences will continue shifting eastward, thus shower chances will continue to diminish over next few hours, with shower and/or thunderstorm chances ending by midnight. As we lose diurnal influences and the 500 mb trough axis slides east, shower coverage will decrease after 00z. Upper ridging will build in from the west and highs should top out in the 80s across the area.
1216 AM CDT Sun May 19 2024 (Tonight) Lingering convection from earlier this afternoon has just about diminished this Sat evening, as an upper trough axis begins to move east of the mid TN Valley. Overnight temps look to be fairly normal for this time of the yr, with early morning lows Sun mainly in the lower 60s/near 60F for most spots.
(Now through Monday) Dry conditions will persist through Monday as deep ridging becomes reestablished across the southeast states. Skies will be mostly clear to clear, along with warmer temperatures and light north winds shifting to the east.
A weak trough approaching this afternoon has resulted in southwest winds 10-20 mph gusting 25-35 mph. Monday is shaping up to be the windiest day of the week as a stronger trough crosses the region. As the trough crosses the area later Monday afternoon and evening, there is low chance (<10%) of a light shower or sprinkle but most areas will remain dry.
An exiting mid to upper level trough to our east has ended all the precipitation areawide, except for a sliver of the far coastal waters where scattered thunderstorms continue. The highest likelihood of this occurring will be across Southeast Texas and Western Louisiana along and north of I-10. For Sunday through Monday night, a dry northwest flow aloft expected between the exiting mid to upper level trough to the east and a building mid to upper level ridge over Northern Mexico. With the increased dewpoints in the lower to mid 70s, maximum heat index values in the mid 90s expected each afternoon.
The western extent of a low-level ridge axis extends west-northwest through the Bahamas and across the Keys.
(Today and tonight) An upper level trough will move through north-central Georgia today. Cooler temperatures aloft with this trough will steepen lapse rates, and residual moisture appears sufficient for isolated to scattered showers and thunderstorms across the eastern half of the area this afternoon. With the cooler temperatures aloft, small hail will possible with storms that develop.
223 AM MDT Sun May 19 2024 - Warmer today. Lead impulse ejects from upper trough over the Rockies. Active pattern continues through the remainder of the week series of troughs move through the Rockies into the Northern/Central Plains. Otherwise, another low pressure system will cross the region Sunday and support breezy winds and scattered afternoon showers and thunderstorms, mainly across SD. A cold front will move through the region Sunday afternoon, with gusty NW winds developing behind the front.
341 AM EDT Sun May 19 2024 A cold front will move south across southern NC and SC Sunday morning.
A weak low-level ridge is now moving toward the Mississippi Valley, and we'll start a period of drier, warmer weather today. Highs this afternoon will be in the 80s, though some upper 70s in the higher terrain is possible in the east. Upper-level flow will be split, but more amplified on Monday, as a deep-layer ridge strengthens across the eastern CONUS. I've favored warmer guidance and have highs in the mid to upper 80s advertised with no mentionable PoPs.
1233 AM CDT Sun May 19 2024 (The rest of tonight) Upper ridging in place and high pressure just off to the east will allow for quiet conditions overnight.
The ridge will continue to keep conditions mostly dry, however, scattered shower and thunderstorm activity will be possible for coastal locations, primarily on the Atlantic side as the sea breeze boundary pushes inland in the afternoon and early evening hours. With south-southwest flow and warming air mass from the overhead ridge, high temperatures today will peak in the mid to upper 90s across much of South Florida, with heat index values up to 110 possible. Overall, the highest chances for showers and storms will be in northern portions of South Florida as low level flow will be southerly.
1213 AM CDT Sun May 19 2024 (This afternoon through Sunday night) WV imagery shows an weak, upper-level ridge in place over West Texas and Southeast New Mexico this afternoon. Tonight, the ridge moves east of the area, courtesy of a PacNW trough digging southeast, putting the area under southwest flow aloft. Leeside troughing on the Front Range ahead of this feature will induce a 40+kt LLJ, keeping the boundary layer mixed, and overnight minimums ~ 6-8F above normal. Sunday, leeside troughing will increase surface winds across the area, adding a downslope warming component to the mix, and increasing thicknesses to provide the first day this spring of widespread triple-digits outside of the Rio Grande Valley.
254 AM MDT Sun May 19 2024 KEY MESSAGES: - An oncoming surface cold front will move in this morning, bringing rain showers and thunderstorm probabilities that will last through the early evening. WEATHER PATTERN OVERVIEW: The cold front arriving today will keep things cool through the early week with below normal temps. A series of weak troughs and disturbances will move their way along the International Border from west to east into the end of the forecast cycle.
(Today through Monday Night) Ridging will gradually take place from the southern Plains into Arkansas the next couple of days. At the surface, the period will begin with high pressure over the region this morning. On Monday, high pressure will shift to the east a bit. Clockwise flow around the high will bring a little more wind than today from the south, and temperatures will be slightly warmer. The system will head toward the upper Midwest, and will drag a cold front this way.
(Today through Monday) The upper level flow this morning is zonal to slightly ridging and this will continue through the short term period. The low level flow is from the southeast. This is bringing warmer, moister air to our CWA.
The low clouds are around 1000 feet with VSBYs around 4-6 miles. This will continue until sunrise, and with some mixing and heating, the low clouds will lift as will the VSBY over South Texas. Monday high temperatures will be a couple of degrees warmer than today as the pattern stagnates and the heat builds up under the ridge.
Weak ridging will keep afternoon highs warming a couple of degrees each day, pushing temperatures into the mid to upper 80s by Monday afternoon.
The passage of a weak cold front earlier today will contribute to some clearing overnight and faster dispersal of the clouds Sunday morning. DialH (This evening through Sunday) Slightly cooler temperatures are expected this afternoon ranging from the upper 50's to mid 60's at the coast to upper 60's to mid 70's across the interior (a few spots may reach into the upper 70's). In wake of today's frontal passage, expecting tomorrow to be slightly warmer across the interior as low clouds will likely be quicker to dissipate. Thus, tomorrow we should see more upper 70's inland while cooler conditions prevail near the coast (upper 50's to mid 60's).
An upper trough is over the Pacific Northwest and northern Rocky Mountains. Upper lift with this trough has increased along with mid-level instability across the area. The upper trough to the west will dig southward on Monday. The highest chances (up to 95%) will be generally along and north of I-80 Monday night. Upper level lift will increase across the area Monday night as the upper trough moves closer. A cold front associated with the upper trough will move into the area Monday night. Low temperatures Monday night are expected to range from the low 50s to mid 60s.
400 AM EDT Sun May 19 2024 A cold front will move south across southern NC and SC Sunday morning.
1206 AM CDT Sun May 19 2024 Upper level troughing influences will continue shifting eastward, thus shower chances will continue to diminish over next few hours, with shower and/or thunderstorm chances ending by midnight. As we lose diurnal influences and the 500 mb trough axis slides east, shower coverage will decrease after 00z. Upper ridging will build in from the west and highs should top out in the 80s across the area.
For today, a drying southwest flow will set up across northern Arizona as a longwave trough develops over the western states.
1252 AM CDT Sun May 19 2024 Surface and upper-level ridge across the region to maintain stable conditions overnight. With mostly clear skies, temperatures are forecast to fall into the low to mid 60s. /05/ (This evening through Sunday Night) A field of fair weather cumulus clouds this afternoon will begin to quickly dissipate around sunset this evening as high pressure at the sfc continues to dominate. Another warm day will follow on Sunday as light SE flow returns in the wake of advancing high pressure. Temperatures will likely run a few degrees warmer on Sunday compared to today with mostly locations reaching into the lower 90s under a field of afternoon cumulus once again.
The highest confidence is at VRB/FPR where TSRA TEMPOs are included from 18/21Z. Beyond that, the forecast remains unusually uncertain, due to a cold front forecast to drop into the area into Sunday. Overnight lows expected in the lower to mid-70s.
longwave trough and approach our area late today and tonight.
An upper level trough encompasses much of SW Canada extending into the NW US with somewhat moist and unstable westerly flow across the Northern Rockies and MT leading to the development of widely scattered showers earlier today. The next disturbance moving through the upper level trough will arrive in western MT later tonight with an area of more widespread precipitation developing over western portions of central MT early Sunday morning. Most airfields remain VFR throughout this TAF period, even as they fall into the low VFR category range.
Temperatures remain in the lower to mid 80s early this morning and dew points are in the upper 70s to near 80, leading to heat indices between 95-100 degrees. The synoptic feature that has been responsible for this oppressive mid-May heat is an expansive mean layer ridge that has been parked over us. This high will finally get shoved eastward starting today as a longwave trough traverses across the Southeast. The front associated with this trough will slide down the Florida Peninsula over the next few 122days.
As the trough moves further south on Monday, central Idaho and western Montana will have continued below-average high temperatures and another round of showers and isolated thunderstorms by Monday afternoon.