Aikyam-Lab/Synoptic-Bench huggingface dataset:
This will be coupled with a trough moving onshore from the Pacific. At the same the Pacific trough will begin moving in from the west and the combination of moisture and instability will lead to a greater coverage of thunderstorms.
An upper ridge will also be across the Four Corners region.
314 AM EDT Sun Jul 23 2017 Upper level ridging will weaken across the area today.
SHORT TERM (Now through Monday): A weak mid-level low will continue to fill as it moves into the upper Texas coast underneath a broad ridge of high pressure located over the Central US.
Nothing had developed in the area or nearby as of 19Z, but there was no shortage of boundaries, with a stationary front along the Wisconsin/Illinois border, another across Lake Superior and Upper Michigan, and a trough in eastern Minnesota.
Otherwise, high pressure across Quebec will bring light north winds and dry conditions overnight and through the daylight hours on Sunday. Our chances for showers increase as an upper level trough will bring widespread showers to the North Country beginning Sunday night and lasting through Monday and into Monday night.
A weak upper trough over British Columbia will allow for clouds and cooler weather today.
Temp decreases will be modest tonight, with most locations in the low to mid 70s by daybreak Sunday. Even with the cooler temperatures, apparent temperatures over portions of northwest Alabama could still approach 105 for a brief time. With more clouds and showers, even cooler conditions will greet the start of a new work week, with highs in the mid 80s to around 90. The extended will once again start out with a upper-level ridge anchored across the central portion of the country.
359 AM EDT Sun Jul 23 2017 High pressure remains off the southeast coast. A weak boundary stretches from central Virginia westward to low pressure over southern Illinois. An upper level trough of low pressure will move over the northeastern US early in the week.
234 AM MDT Sun Jul 23 2017 Large scale ridge has amplifies over the western US, with NW flow over the Northern Plains. If there was a period to monitor it may be Monday/Monday night with better instability developing as southerly flow in the low levels brings higher Tds back to our CWA.
An upper-level low moves into the Great Lakes region as troughing digs into the Midwestern States today. A weak upper low is set up over Southern Louisiana, but doesn't seem to offer enough lift across Central AL to increase storm coverage. High temperatures expected to reach into the low to mid 90s with dewpoints in the mid to upper 70s. The trough axis slides southward slightly this evening and into the overnight hours as a cold front stretches through the TN Valley.
145 AM EDT Sun Jul 23 2017 Broad area of low pressure will move through the Central Great Lakes through Sunday. A cold front will move south across the area late Sunday ahead of a trough deepening aloft. High pressure will build southeast out of Canada across the Great Lakes during the first half of the week. Scattered showers and thunderstorms expected to re-develop on Sunday with diurnal heating ahead of a trough dropping down from the north. A trough will be exiting the region off to the east on Monday.
If clouds can hang on longer into the afternoon, this will cause temperatures to be slightly cooler. Where the sun comes out, highs in the low to mid 90s will occur.
Once the cold front passes those areas around mid-afternoon, heat index readings should drop back into the mid 90s.
Little changes through the near term period as the local forecast area remains sandwiched between weak mid/upper level lows over the western Gulf and western Atlantic. At the surface, high pressure over the central and northern Gulf is reinforced, with winds increasing slightly and shifting to more westerly as a result. High temps continue to run in the low 90's inland and upper 80's along the immediate coast, with the only chance for relief coming from a passing afternoon thunderstorm.
High pressure and dry conditions will persist today and Monday.
For Sunday afternoon and early evening isolated showers and thunderstorms over the higher terrain will be possible due to the lingering moisture and day time heating. The upper ridge axis starts to slide east Monday. The ridge continues east into the plains and allows the next moisture surge to push northward. After only a day to day and a half the models now want to build the ridge back over the Four Corners which would allow convective activity from lingering moisture but keep the tap to the deeper moisture south and east.
335 AM CDT Sun Jul 23 2017 (Today and Tonight) A weakness in the upper level ridge will continue across West Central Texas today. Overnight lows will mainly be in the low to mid 70s. However, the upper level high begins to strengthen at that point and the remainder of the work week looks hot and dry.
The forecast is dry late tonight and Sunday a weak area of "cooler" air moves into wrn/ncntl Neb.
A wind shear axis associated with a mid- and upper-level trough across the northern Texas Coast is evident on water vapor imagery. Northeasterly to easterly flow is occurring over the region due to the trough's relative position with slight divergence implied due to weak cyclonic vorticity advection this afternoon. The hazardous weather outlook also reflects the high heat indices.
GOES-16 water vapor imagery shows the upper level low centered directly over the region and it will continue to progress westward during the overnight hours. The 00Z LCH sounding sampled a PWAT near 2 inches so showers and thunderstorms will be possible during the overnight hours as the upper level low progresses westward. /issued 348 PM CDT Sat Jul 22 2017/ An upper level low is depicted on water vapor and upper air analysis across the southern Louisiana coast and adjacent Gulf waters. Rua The mid/upper level low will meander across the immediate region through Sunday before beginning to weaken on Monday.
353 AM PDT Sun Jul 23 2017 Temperatures will rise back to above normal levels this weekend as high pressure strengthens over the region.
The main story will continue to be heat with well established high pressure and upper level subsidence dominating the region.
Very warm temperatures today, about 5 to 10 degrees above normal and near 100 in the lower valleys, as southerly flow bringing the moisture also brings heat.
A bit warmer today in the midlevels by a few degrees, so expect less coverages compared to yesterday.
Band of sc associated with weak inverted trough may initially slow warmup this morning and cooler airmass in place so limited temperatures to the 70s today.
631 AM EDT Sun Jul 23 2017 High pressure continues to dominate the weather until late tonight. Low pressure moves in from the west on Monday and tracks south of the area.
Today Through Monday Night The high pressure will weaken somewhat over the area for the short term period. The cold front will move to near the Missouri border today. Temperatures will be a bit cooler on Monday with highs mainly in the low 90s.
Plenty of cloud cover and afternoon convection is expected to really limit heating today and will maintain the 8-10 degree cooler than normal temperature forecast for today. The inverted trough that has been helping to bless us with all the convection is expected to get caught up in the developing S-SW mid-level flow tonight through Monday driving the somewhat more consolidated closed (by Monday morning) feature north.
A cold front will move through the region Monday, shifting winds to the northwest.
A cold front moving through Sunday afternoon could drive some stronger thunderstorms towards Lansing and Jackson. expect showers and isolated thunderstorms after midnight across the northern zones as vigorous short wave trough with closed upper low approaches in fast northwest flow regime. This trough will also be driving a cold front through Sunday evening. Once the storms go past there will be a few instability showers remaining through Sunday night in cyclonic flow which could be diurnally enhanced on Monday before the upper trough axis moves east and sfc ridging builds in for Monday night.
Expect temperatures to still be ranging in the low 90s with heat index values around 100 for areas south of highway 36.
A cold front will arrive late this evening, bringing breezy to windy conditions across the Inland Northwest.
High pressure continues to be the dominate feature in the upper levels.
Thunderstorm chances will continue for Monday before cooler and drier conditions work into the region for Monday night.
329 AM CDT Sun Jul 23 2017 Clusters of showers/storms should continue to gradually shift south and become less numerous this morning, along and ahead of a 700-500 mb trough axis.
Temperatures will begin to moderate on Sunday as a weak upper level trough begins to develop off our coast. But then by the latter part of the week, high pressure looks to build back in again resulting in a return to warming temperatures.
The HRRR and some other mesoscale & synoptic models show some activity developing along the surface cold front where there is just enough moisture to allow for it. The forcing is also associated with the upper trough.
A rich theta-e ridge remains in place, extending from Chihuahua thru Texas and into AR and beyond. W/multiple residual boundaries knocking about, and continued upslope return flow, chances are good for redevelopment of widespread convection this afternoon, especially over the higher terrain. These chances will dwindle after today as the upper trough over the Texas/LA coast moves east and the upper ridge recenters over Texas and strengthens. This will confine any convection, if any, to the higher terrain out west into the extended.
1136 PM MDT Sat Jul 22 2017 Most of the late afternoon convection that developed over the high plains has dissipated. Cumulus and some storms are developing in the convergence along this trough. Heights aloft rise on Sunday with the midlvl ridge axis located near the Laramie Range by the aftn. After slightly cooler temps today, we will see around 5 degrees of warming at most locations. Medium range models are in good agreement with overall pattern progression in retrograding the upper high west from the southern plains towards the four corners. As this occurs, southwest flow around the periphery of the upper high will be effective in advecting monsoonal moisture into the intermountain west.
Each day this week there is a chance of rain in the Mid-South as either frontal systems move across the area or afternoon and evening thunderstorms develop under a high pressure system.
404 AM EST Sat Feb 17 2018 An area of low pressure will move just southeast of the region today and an upper level disturbance will move across the area later today bringing the potential for precipitation. High pressure will allow for dry conditions on Sunday. An area of low pressure will move just to the southeast of the region today. High pressure will then work into the region for the day on Sunday. WAA on Sunday and plenty of sunshine will allow temperatures to climb into the middle 40s to the lower 50s.
1130 PM CST Fri Feb 16 2018 A mix of IFR/MVFR expected overnight as ceilings fluctuate with cold front moving across the region.
1248 AM EST Sat Feb 17 2018 High pressure will give a sunny start to the day, but clouds will increase and thicken from mid day onward. High pressure builds in overnight bringing clearing, with light winds ending the lake fetch. Fast moving southwest flow and baroclinic make it difficult to place the low and snow amounts. Still plenty of time before an Advisory is needed, especially given the low confidence. Mild air behind the low will likely end up melting some of the snow by afternoon, making this a low impact event in many ways. No major changes to the overall thinking regarding the pattern evolution for the upcoming week with a broad trough becoming established over the West and a ridge along the East Coast.
/issued 357 PM EST Fri Feb 16 2018/ Short Term (Tonight-Sunday): High pressure ridge overhead will provide continued dry weather with above average temperatures over South Florida through the weekend.
349 AM EST Sat Feb 17 2018 High pressure will bring a nice start to the weekend.
Another warm day is in store with temperatures this afternoon reaching into the low 80s, well above normal.
244 AM EST Sat Feb 17 2018 Low pressure system approaches today/tonight. High pressure Sunday.
An area of low pressure and weak cold front could bring some rain and snow to the area Saturday.
We still expect some expansion southward, but it does appear the highest rain chances will come across the northern third of the forecast area. As that occurs surface winds will become southwesterly bringing back warmer air and increased moisture. Tomorrow a cold front will drop across the region from the northwest ushering out any left-over precipitation. This cold front won't be near as strong as todays.
The upper level low that has been off the Baja California coast will finally start to shear out and move our way by Sunday.
357 AM EST Sat Feb 17 2018 A cold front will stall well to our south early this morning as the center of cool high pressure slides by to our north. Low pressure will track along the stalled front, passing by to our south late today and tonight. High pressure will return for Sunday and then will move to our east.
Fog will continue to plague the area each night as cold frontal boundaries tease us through the weekend. After Sunday's cold front all but dissipates and move north, the foggy mornings should begin to improve.
A short wave trough looks to shift through the lower Great Lakes by the end of the day with the right entrance region of the upper jet set to track straight through the area. Snow ratios have been adjusted accordingly, and accumulation potential, especially during the daytime hours, has been held back significantly other than in the highest terrain. Even with that in mind, snow amounts from this afternoon into the evening will likely yield at least widespread advisory accumulation in the terrain, with possible warming criteria on the highest peaks. This may yield a period of freezing drizzle, however given the proximity of the lifting profile to the bottom of the dendritic layer, it would seem poorly formed flakes are more likely in the terrain than freezing drizzle at the moment.
After a chilly start today, southwesterly surface winds have brought warmer air into the region. Overnight into Saturday morning, this trough will cause enough lift to produce some light snow showers over northwest Iowa. During the daylight hours, a subtle secondary trough could bring another dusting to the tri- state area, but again, this looks to be of minimum impact.
418 AM EST Sat Feb 17 2018 High pressure over the region will result in a pleasant winter day. Quick moving low pressure will move south and east of New England Tonight and early Sunday, bringing the potential for snow.
410 AM EST Sat Feb 17 2018 An area of low pressure will bring precipitation to eastern Kentucky today, as it makes it way across the Tennessee valley. The snow should be gone by around noon today, as temperatures will have warmed well above freezing by then. Temperatures are expected to remain slightly below normal today, with highs in the low to mid 40s on tap across the area. They all depict a semi-static ridge through the southeast holding broad and deep southwest flow in place over the Tennessee and Ohio Valleys. This ridge will shift a bit through the seven day forecast but its influence will be dominant for the weather across Kentucky.
High pressure ridge will be centered to the Southeast this period. While a weakening cold front will slide into SE GA Tonight, little impact, outside of a few extra clouds across Northern counties is expected.
248 AM CST Sat Feb 17 2018 06Z surface data has high pressure over the Ohio Valley with a developing low in southeast Colorado. The rain/snow mix should make it as far north as the highway 30 corridor during the afternoon. The best chances for precipitation are east of the Mississippi where the forcing maximizes as warmer air flows in from the south. As for snowfall amounts, areas along and south of the highway 30 corridor will see a dusting of accumulation at best. North of the highway 30 corridor accumulations will range from a dusting to less than an inch. Tonight, quiet and dry conditions will be seen across the area as the next high pressure moves through the Midwest.
The flow aloft will be nearly zonal through Saturday night before ridging builds back in from the east. A weak cold front will push into our CWA Saturday night before stalling on Sunday.
While the operational deterministic models are in fairly good agreement on a swath of a quarter to a third inch of QPF, the operational GFS is on the low side of GEFS QPF guidance. Additionally, isothermal profiles for areas south of Interstate 94 suggest potential for a period of light freezing drizzle.
338 AM CST Sat Feb 17 2018 A weak low pressure system and broad upper level trough will cross the region this morning. A stronger low pressure system will cross South Dakota later tonight through Sunday. Models soundings still support the possibility of freezing drizzle with minor ice accumulations possible. The latest models continue to advertise the development of a positive tilt mid level trof over the western conus, extending northeast into the Western High Plains.
Drier and warmer conditions will develop into the weekend.
Increasing southerly flow on the back side of the ridge axis tonight will help hold low temperatures in the upper 20s/low 30s overnight. Even warmer weather is still on track for Sunday as that frontal boundary lifts back to the north as a warm front and flow alfot transitions southwest ahead of a trough digging into the Pacific Northwest. As warm as it sounds, keep in mind the warmer air will be accompanied gusty southerly winds in a tight pressure gradient.
Highs are expected to reach the 40s and 50s, but the gusty winds will make it feel at least 10 degrees cooler. Late Saturday night into Sunday morning, we will see strong southerly flow develop ahead of another trough moving into the western CONUS. ranging from the upper 50s in Nebraska to near 70 degrees in parts of northern Kansas! Timing continues to vary, but a cold front is expected to make its way through the area Sunday afternoon into the evening, shifting winds back to the northwest.
As for tonight, high pressure will bring clearing skies and light winds. Lows will be near freezing. Winds will become southeast on the back side of the high.
At the surface, cold front that blew through last night is now situated from northern LA into south TX. May see a brief period of rain/snow mix but with temps hovering at or just above freezing, not expecting much in the way of accumulating ice.
The front lifts north Sunday as a warm front which will further increase the low level moisture over the region and allow for continued isolated, mainly light, showers.
The high pressure will slide to the east tonight with southerly winds continuing through the night.
1239 AM EST Sat Feb 17 2018 A cold front will move through the area tonight.
NAM Bufkit soundings continue to suggest that the precipitation will begin as snow due to wetbulbing effects and transition to rain as the lower atmosphere continues to warm during the late morning and afternoon hours. Current soil temperatures across the area are in the lower 40s and air temperatures will be near freezing or slightly above freezing during the period of snow, which should preclude any significant impacts. With the lighter winds and clearing skies, temperatures to drop into the low 20s to low 30s. Some concern about precip type initially because of the colder air and evaporative cooler aloft. However, the ground will be a bit warmer so most of it will melt on contact. Despite the cloud cover and precipitation, temps to warm up into the low 40s to low 50s on Saturday.
Will also see some gusty winds in some of the higher elevations and foothills.
Warm front has pushed through western and central North Dakota with afternoon highs reaching the 20s and 30s for all but the far northeast CWA where upper teens held on around the Turtle Mountains. For tonight, a weak cold front will drop south through the forecast area. It should be noted that a loss of ice crystals in the column south of I-94 will reduce snowfall amounts for these locations with a glaze of ice not out of the question in freezing drizzle.
1139 PM CST Fri Feb 16 2018 A cold front will move from west to east through the Northland tonight and early Saturday. Very light snow is possible across the Northland overnight into Saturday in advance of the cold front because of some large-scale forcing from the upper trough.
CAA has brought cooler temperatures into the region today with temperatures this afternoon running generally in the 30s. High pressure is building into the region late this afternoon but will quickly traverse the CWA shifting east of the area by midnight. This will lead the low temperature tonight to occur around midnight as winds will pick up out of the south after midnight. Little to no accumulation would be expected with temperatures hovering right around freezing.
As a result, a few changes to the lows tonight (not big) but may not see temps fall to below 60 in some spots as first thought especially with the dew points staying up. Ergo, there is some potential for the fog to spread farther inland and become dense at times before the low level jet improves things (improvement may only be slight).
939 PM MST Fri Feb 16 2018 The synoptic pattern featured a closed low off the southern California coast with northwest flow over the Pacific Northwest this afternoon. Cirrus emanating from the low was sweeping over areas along and south of the I-70 corridor.
Sfc temps tngt look to rmn abv freezing as persistent cloud cover wl hinder cooling somewhat. A brief respite in the wet weather wl occur Sat night and early Sun as a weak rdg of high pressure blds into the FA. The high wl shift quickly Ewd, with clouds and rain chances returning fm the S by Sun aftn.
On the leading edge of the shield of precip, temperatures will be around freezing and light snow will be likely. As warm advection with southerly winds kicks in, temperatures will slowly creep upward above freezing from southwest to northeast and the light snow will change to just a cold rain. There could be an isolated slick patch or two on elevated bridges or road surfaces. Southerly winds will increase on Sunday with a return to much warmer weather. A large upper level trough will develop and dig across the western U.
For now we will mention areas of fog forming mostly over the lower half of the forecast area tonight or generally along and south of a weak frontal boundary that moves south and stalls over the lower part of the forecast area overnight. Due to the uncertainty where the front actually stalls we will hold off on any fog advisories over land attm though will likely issue a dense fog advisory somewhere in the lower half of the forecast before the night is out. The higher rain chances will be over northern and western sections of the forecast area or mostly west of I-65 and north of I-10. For Sat expect fog and clouds early in the day followed by some gradually clearing with continued mild temps, though about 3 to 5 degrees cooler than today.
130 AM EST Sat Feb 17 2018 High pressure will build east across the southern Great Lakes overnight, then continuing towards New England. As it departs, low pressure will track through the Tennessee Valley to the East Coast Saturday followed by high pressure building into the Ohio Valley on Sunday.
113 AM EST Sat Feb 17 2018 A weak cold front will move over the area tonight, then become stationary across the region this weekend.