Aikyam-Lab/Synoptic-Bench huggingface dataset:
639 PM CDT Tue May 23 2017 Large upper level low was located over northern Iowa this afternoon and will continue to drop south toward Missouri by Wednesday morning. Scattered showers continue to pop up across the CWA this afternoon around the backside of the low. Wednesday looks dry as the above mentioned upper level low continues to dig south and east allowing weak upper level ridging to build overhead.
There will remain a chance for shra/tsra thru the day but a greater chance later in the afternoon/evening as a band of convection pushes across the peninsula ahead of a cold front. Seas will build to 3-4 ft near shore and 4-5 ft offs ridge.
1131 PM CDT Tue May 23 2017 Northwest winds behind today's cold front have backed to the west and fallen below 10 kts this evening, and will remain light the rest of the night. Otherwise, VFR conditions can be expected as dry air and subsidence dominate in the wake of a passing upper level trough. We're now on the back side of the upper trough and mid level drying will continue. /ISSUED 400 PM CDT Tue May 23 2017/ By mid-afternoon, a cold front had moved through the entire CWA. Outside of the severe thunderstorm watch, thunderstorms will still be possible until the mid-level trough axis passes, but with tall/skinny CAPE, deep showers should be the primary mode.
Forcing aloft is aided by the presence of the strong jet streak analyzed at the base of the trough. /issued Issued by National Weather Service LITTLE ROCK AR/ Showers and thunderstorms are expected across the area tonight, as a cold front sweeps through the forecast area. Aloft, a closed low over the Midwest will drop down into the midsouth region by Wednesday night, and will keep chances for showers and thunderstorms in the forecast through that time frame.
Main aviation concerns tonight will be the potential for strong storms developing along a southward-moving cold front. Slight risk of severe weather across the Rio Grande valley and Short Term (Tonight through Wednesday night): The combination of a 500mb trough across the central United States and a weak cold front moving through the CWA tonight will allow scattered showers and thunderstorms. Temperatures will be slightly cooler Wed afternoon compared to the previous couple of days but will still be very warm across the CWA.
By early this afternoon, the mid-level trough axis was progressing eastward across the CWA with the associated closed mid-level low located over southern Minnesota/northern Iowa. Isentropic lift on the backside of this exiting trough was resulting in scattered showers developing over southern Nebraska, which were sliding southeastward across north central Kansas. With the mid-level trough remaining over Missouri through the day tomorrow, nearby showers in far western Missouri will keep cloud cover over eastern Kansas through much of the day.
739 PM EDT Tue May 23 2017 High pressure will bring dry weather and a mix of sun and clouds to NY and PA through Wednesday.
Instability has developed south of the warm front, leading to thunderstorms developing along and just north of the boundary. Center of the upper low will drift south across Iowa and Missouri, but the upper level trough axis will extend north across Wisconsin through the night. As the low moves south, think precip chances will come to an end over north-central WI by late evening. Eastern WI will not be as lucky, as deeper moisture will rotate around the trough and across eastern WI from about mid-evening through the overnight hours. With ample cloud cover, lows will range from the low 40s north to upper 40s south. The upper low will continue to move to the southeast across the mid-Mississippi Valley.
A cold front will sweep through Western Washington this evening, bringing windy conditions to areas near the Strait and Admiralty Inlet.
A cold front pushed through the area early in the day with continued upper level energy cycling around the main upper level closed low which was up in Iowa. The short term forecast will focus on the upper low tracking south through the area and resultant cool temperatures/cloud cover and lingering scattered showers. For tonight, the upper low will drift into the area from Iowa, but scattered shower activity will diminish considerably after dark with the loss of daytime heating and instability. Additional shower activity will be possible on Wednesday, mainly in the afternoon, as the upper low slowly drifts southeast across the CWA and instability increases again. The low will track to the southeast of the area Wednesday night and showers should come to an end.
/issued Issued by National Weather Service LITTLE ROCK AR/ Showers and thunderstorms are expected across the area tonight, as a cold front sweeps through the forecast area. Aloft, a closed low over the midwest will drop down into the midsouth region by Wednesday night, and will keep chances for showers and thunderstorms in the forecast through that time frame.
525 PM MDT Tue May 23 2017 Isolated light showers dotting mainly the Neb Panhandle this afternoon on far west side of upper low over Iowa. A short upper ridge will pass across the region Weds boding for warmer and dry weather with mainly clear skies.
900 PM CDT Tue May 23 2017 Diurnally driven showers have all but ended as the sun sets, with the upper low currently spinning over Iowa.
For 00Z Aviation discussion below Scattered showers/isolated thunderstorms were noted this afternoon near the core of the upper low centered near La Crosse, Wi. The best moisture advection associated with the upper low was in southeast Minnesota this afternoon and this is where the best concentration of showers had occurred.
For 06Z Aviation discussion below Scattered showers/isolated thunderstorms were noted this afternoon near the core of the upper low centered near La Crosse, Wi. The best moisture advection associated with the upper low was in southeast Minnesota this afternoon and this is where the best concentration of showers had occurred.
Muggy and mild overnight conditions with lows in the low/mid 70s.
As the trough moves out of the CWA, skies will slowly start to clear out from west to east. Areas east of the James River will have temperatures in the lower 40s. Otherwise, an upper ridge will begin to settle across the area, bringing a pleasant day with mostly sunny skies and light winds on Wednesday. Highs will be from the lower 60s across southwest Minnesota, to upper 60s across southeast South Dakota. A ridge of high pressure will quickly exit east on Wednesday evening and will allow southerly flow to develop across the area overnight. This will bring warmer lows with mid 40s in northwest IA and 50 to 55 in south central SD.
644 PM CDT Tue May 23 2017 Storms occurring ahead of the cold front will be moving across the terminals from 00Z at KUTS to about 04-05Z at KGLS. /ISSUED 438 PM CDT Tue May 23 2017/ Surface analysis as of 1 PM CDT showed an approaching cold front stretching from Del Rio to Waco towards Shreveport, with a weak prefrontal wind shift entering portions of the Brazos Valley.
Dry and Cooler) During the next 24 hours, West Central Texas will transition from a wet weather pattern to a dry patter. The upper low will continue to move east, and skies will clear. Winds from the north and northeast tonight will continue to bring cooler air. For tomorrow, look for sunny skies, light winds, and afternoon highs very close to seasonal normals, mainly in the lower to mid 80s.
615 PM CDT Tue May 23 2017 A large amplitude vertically stacked low pressure system resides over the northern plains creating most of the weather impacts in this region for the next 48 hours. This low will quickly push to the south through eastern MO Wednesday morning sparking off another around of showers over central MO which will also have limited thunderstorm potential and last off and on through sunset as the low starts to push east. Temperatures will remain below average on Wednesday as well with even a slight decrease of a couple degrees with the low overhead.
740 PM EDT Tue May 23 2017 High pressure will bring dry weather and a mix of sun and clouds to NY and PA through Wednesday.
An upper level disturbance extending down from the Plains across central Texas will move east tonight and quickly push a cold front across the forecast area during the evening hours. /issued 359 PM CDT Tue May 23 2017/ Afternoon surface analysis shows a cold front extending from Texarkana southwest to Austin. Satellite imagery shows thunderstorms already developing along the cold front as it progresses to the southeast. High pressure will build over the region during the day on Wednesday resulting in drier and cooler conditions.
A few showers and thunderstorms are making their way into the western part of our CWA associated with a weak low pressure system. An area of SHRA/TSRAs wl develop ahead of a cold front this evng and spread across the area.
/Tonight through Wednesday/ Upper low will continue to dominate the weather in the short term. With cool temperatures aloft associated with this low, numerous showers have developed across central Iowa this afternoon. Will continue to see some threat of showers overnight in vicinity of the low as it slides southward into Missouri and will continue with low pops overnight. The upper low will continue to influence the weather into Wednesday with plenty of cloudiness to start the day and thermal trof lingering over the state. A few showers may continue across the area, however this threat will diminish as the cooler temperatures aloft depart the area as the low pulls away. Some drying in the low levels in the west will likely lead to some partial clearing in the western half of the state later in the day.
922 PM CDT Tue May 23 2017 A cold front was located from Alexandria to Beaumont and continued to move southeast across our area. An upper level disturbance extending down from the Plains across central Texas will move east tonight and quickly push a cold front across the forecast area during the evening hours. /issued 359 PM CDT Tue May 23 2017/ Afternoon surface analysis shows a cold front extending from Texarkana southwest to Austin. Satellite imagery shows thunderstorms already developing along the cold front as it progresses to the southeast. High pressure will build over the region during the day on Wednesday resulting in drier and cooler conditions.
In the middle and upper levels(700-200 mb), latest available IR imagery overlaid with model streamline analysis as of 900 pm, depict an unseasonably deep longwave trough building slowly eastward with an associated well aliened cold core cyclone moving southeast away from Iowa. Much of the Gulf of Mexico is beneath the southern periphery of this trough, or underneath deepening middle and upper cyclonic flow that is pushing towards Florida. At the surface and in the lower to middle levels,(Surface to 700 mb), latest IR imagery overlaid with land and marine surface observations and analysis as of 900 pm, detail a strong late season cold front trailing south southwest to East Texas from a 1005 mb low over Southern Minnesota. Temperatures across the islands remain in the lower 80s with typically humid dewpoints in the middle 70s.
905 PM CDT Tue May 23 2017 As an upper level low drops southward through Iowa this evening bands of showers continue to wrap around the low pushing eastward through central IL.
A low pressure system will strengthen over the Ohio Valley tonight and slowly lift north into the Great Lakes region Wednesday and Wednesday night.
505 PM MDT Tue May 23 2017 Latest upper analysis shows the closed low moving northeast with a ridge approaching from the west. At the surface winds continue to increase as the low level jet over the forecast area begins to mix down to the ground. In fact the low level temperature field was cooler last night over Eastern Colorado and lows only fell into the mid 30s. A warm front will move through the forecast area from the west.
/issued 707 PM CDT Tue May 23 2017/ For the ArkLaTex, cold front right overhead KSHV/KLFK and moving through KELD/KMLU into the mid evening hours.
Showers will persist in the northern CWA due to lingering mid-level deformation as upper low shifts southward.
South-southeast sfc winds will increase Wednesday ahead of a cold front which will enter eastern Montana Wed late aftn. Warmer on Wednesday with highs 65-70 in most areas.
A Pacific cold front will move across the area on Wed. Chances for afternoon showers and storms looked best in the far eastern zones where SSE flow will moisten up the lower levels.
608 PM CDT Tue May 23 2017 Expecting temps to gradually decrease the rest of the evening with the passage of a cold front earlier today. Most of the scattered light showers that developed on the backside of the upper level low have departed the CWA this afternoon. Although still cooler than normal, Wednesday looks to be a much nicer day than today as weak ridging moves into the area.
At the surface, the ridge axis has been shunted to south of the state as low pressure moves through the southeast with a trailing cold front. An approaching cold front will bring deteriorating conditions to the region for much of Wednesday, with lowered cig and vis in showers and thunderstorms possible starting in the morning and continuing through the forecast period.
509 PM MDT Tue May 23 2017 Upper low has shifted over southern MN/northern IA, with a 100 kt jet in northerly flow over the western Dakotas. Temperatures across the southwestern and central SD plains will dip into the low to mid 30s, and frost is expected to develop by morning. The upper ridge will result in a mild and dry Wednesday, with highs in the 70s to lower 80s.
An upper level ridge is current centered over Northern California leaving much of northwest California under clear skies, except for the normal stratus along the coast.
This is in response to an approaching strong upper trough.
1154 PM CDT Tue May 23 2017 Large upper level low was located over northern Iowa this afternoon and will continue to drop south toward Missouri by Wednesday morning. Scattered showers continue to pop up across the CWA this afternoon around the backside of the low. Wednesday looks dry as the above mentioned upper level low continues to dig south and east allowing weak upper level ridging to build overhead.
Drier and cool air will continue through the overnight with atypically strong northwest flow aloft as the upper level low pressure system steers southward through Missouri. Winds should taper off by early to mid evening as the lower atmosphere decouples, but still retain some northerly component much of the night. A quick and strong warmup will ensue Wednesday with the upper low heading eventually east towards the mid-Mississippi valley and upper heights build across the southern high plains.
1159 PM CDT Tue May 23 2017 A cold front pushed through the area early in the day with continued upper level energy cycling around the main upper level closed low which was up in Iowa. The short term forecast will focus on the upper low tracking south through the area and resultant cool temperatures/cloud cover and lingering scattered showers. For tonight, the upper low will drift into the area from Iowa, but scattered shower activity will diminish considerably after dark with the loss of daytime heating and instability. Additional shower activity will be possible on Wednesday, mainly in the afternoon, as the upper low slowly drifts southeast across the CWA and instability increases again. The low will track to the southeast of the area Wednesday night and showers should come to an end.
631 PM CDT Tue May 23 2017 Thunderstorms associated with an upper trough have moved east and south of the forecast area as the trough axis moves southeast across the region. /ISSUED 400 PM CDT Tue May 23 2017/ By mid-afternoon, a cold front had moved through the entire CWA. Outside of the severe thunderstorm watch, thunderstorms will still be possible until the mid-level trough axis passes, but with tall/skinny CAPE, deep showers should be the primary mode.
A few areas along the Buffalo Ridge in west central Minnesota had wind gusts of 40 to 50 mph after midnight which was associated with a storm system developing in the Plains this morning. A frontal boundary was moving across the western Dakotas early this morning, but temperatures behind this front are actually warmer than ahead of it. However, I wouldn't be surprised to see a few showers are possible along the Iowa border late this afternoon, and depending upon temperatures, some sleet or freezing rain is possible. Cooler air will filter across the region late tonight, but it will only allow temperatures to fall into the 20s as the air mass is relatively mild /Pacific origin/ compared to a few days ago.
SHORT TERM (Now through Monday): Midlevel trough is sweeping across the four corners region, and is already spreading high cirrus into south Texas. Sea fog won't fully begin until after winds decrease, with best chances after midnight along the immediate coast, along with moisture pooling ahead of the approaching cold front. High temperatures will be 5 to 7 degrees cooler than Sunday, with a considerably drier airmass as well.
Regional radars all indicate virga and most of the high resolution models advertise some rain showers across much of the forecast area after sunrise. As wave moves over and then east of region later this morning and afternoon, a cold front will sweep quickly across the region. Guidance numbers came in warmer for highs today, but didn't bite too hard on those numbers as solid downslope flow will be tempered by cloud cover, virga and eventually some light rain showers before the cold front puts an end to diurnal warming.
Today's highs will also be below normal for one more day, with temperatures near 50 along the Altamaha River to the lower 60s across Marion County.
419 AM MST Sun Jan 7 2018 Upper trof across CO will continue to shift southeast this morning. North winds will remain breezy with gusts to 25 to 35 kts this morning behind the cold front. Lee trof redevelops overnight across the lower eastern slopes/adjacent plains which should keep min temps relatively mild where westerly drainage winds set in. Upper ridge slides across the region, providing for a dry and mild day. Look for highs in the 40s to mid 50s for the high valleys, and 50s to lower 60s for the plains.
High pressure will remain in tact this period with easterly winds.
342 AM MST Sun Jan 7 2018 Mountain snowfall is beginning to decrease early this morning as upper level trough axis passes to our east. They should mix with a little snow behind a cold front which has just pushed through, before more significant drying comes in from the north and ends the scattered showers early this morning. In the high country, the showers will likely linger a few hours longer with orographics aiding light precipitation. On Monday, upper level high pressure will dominate the Rocky Mountain Region, with mild and dry weather across all of north central and northeastern Colorado.
1026 AM EST Sun Jan 7 2018 As high pressure moves east tonight and Monday, expect warming temperatures. A trough moving by on Monday will produce some light snow, mainly for northern areas.
Surface wise, a strong, arctic region of high pressure (1041 mb) is centered over Virginia and the Carolina coast. With this, a lengthy ridge extends down the eastern seaboard and down the entire Sunshine state. In wake of a minor short wave trough migrating eastward and across the eastern portion of the Florida peninsula, even drier air has filtered into our region.
Strong isentropic lift will eventually get some light sleet or freezing rain going near the Mississippi River toward mid morning, then rapidly overspread western Illinois through midday. Initial warm wedge of 2-3C around 850 mb across the Illinois River valley remains supportive of some sleet/freezing rain initially, trending more toward light snow this evening before ending as some light freezing rain/drizzle.
Otherwise expect windy conditions this afternoon first out of the W then becoming N as cold front blows through. /issued 247 AM CST Sun Jan 7 2018/ Upper level trough across the central Rockies will barrel across the southern high plains today dragging a Pacific front through the forecast area. Will go on the higher side of guidance for high temperatures today due to strong downslope flow.
First, air temperatures are warmer than previously thought, especially in our southern and western zones, with several sites already at or above freezing and unlikely to cool down given the warm advection regime we're in.
912 AM EST Sun Jan 7 2018 Brutal cold continues into this morning as Arctic high pressure builds into the area from the west. As the high moves east today and Monday, expect warming temperatures. A trough moving by on Monday will produce some light snow, mainly for northern areas.
The above mentioned mid-level trough along with a cold front will likely produce a round of showers and storms this evening, especially along and east of the I-35 corridor north of San Antonio.
540 AM CST Sun Jan 7 2018 A weak low pressure system will slowly move through Northern Oklahoma and Southeast Kansas today. This increased moisture, coming over a shallow cold air with very cold ground raises the specter of periods of freezing drizzle over parts of the CWA this morning. Additionally, it appears any freezing drizzle will be rather short lived before the WAA changes the freezing drizzle to straight drizzle by noon. By the afternoon, this low pressure system will move off to the east and the winds will kick around to the west and northwest.
Further south across the rest of western Montana into north-central Idaho, it will be a relatively dry day aside from some showers on the higher terrain. Weak high pressure will briefly take hold on Monday, which may allow for some patchy freezing fog in the morning.
Upper level jet will nose into the area from the northwest or on the south periphery of the upper trough today.
A quick update this morning to allow the Freezing Fog Advisory to expire. Will continue the fog advisory at least a little while longer and see what could materialize, most temperatures are below freezing, and we have had reports of slick roads from Idaho Falls northward. High pressure moves in and stratus and fog will be the main problems until Mon night.
A weak cold front will move south across West Central Texas tonight, and the winds will become west to northwest with speeds of around 10 knots. /issued 319 AM CST Sun Jan 7 2018/ (Today and Tonight) Another cold front will move across West Central Texas today and bring winds from the north, along with possible showers. For tonight, an upper trough associated with this cold front, will move farther east taking the potential for showers with it.
637 AM EST Sun Jan 7 2018 High pressure will build over the region marking the beginning of a moderating trend in temperatures. A weak frontal system will approach for Monday followed by high pressure for midweek. Nighttime blended satellite imagery shows the last of the low clouds retreating north into NY. High pressure crossing the region today will mark the beginning of a moderating trend in temperatures.
Upper trough exits the eastern seaboard this morning moving into the Western Atlantic while next U. trough dives from the Southern Rockies today into the NW Gulf Coast region tomorrow. At the surface, large and cold high pressure centered over the Carolina Coast this morning to move into the W Atlantic with easterly low level flow increasing moisture and temps today.
However, across roughly the eastern third of the cwa, sfc wet bulb temperatures will continue to be at or below freezing. By sunrise, temperatures will be at or just below freezing over our eastern sections.
Radar echoes are diminishing away toward the SE and an overall quiet forecast period looms ahead, aside from the chances for freezing fog overnight. BMickelson Previous discussion: Synoptic Setup: Forecast begins with zonal to northwest flow over the High Plains of the US and Canada. To the west a ridge/trough couplet is developing off the west coast of North America with more couplets directly behind over the Pacific.