Aikyam-Lab/Synoptic-Bench huggingface dataset:
Low pressure to the east continues to bring cooler air from the north. Look for overnight temperatures to drop below freezing by Wednesday morning for most of the area, while afternoon temperatures begin to warm for the region as high pressure returns by the weekend. Low pressure to the east continues to bring cooler air from the north. Look for overnight temperatures to drop below freezing by Wednesday morning for most of the area, while afternoon temperatures begin to warm for the region as high pressure returns by the weekend. A cutoff upper low will continue to spin in portions of Utah and Colorado for Wednesday, with a stiff northerly breeze again felt across the area. On Thursday, models are showing the low filling and moving east with heights rising in response to a building upper ridge to the west.
Although, a cooler night is in store as temperatures decrease into the the mid to low 30s across northern Minnesota and Wisconsin. Further to the south across northeast Iowa and southern Wisconsin, slightly higher overnight temperatures are expected to be in the low to mid 40s. Thursday will bring a welcoming break from this gloomy and wet weather as high pressure slides into the region from the northwest.
The tropical tropospheric trough (TUTT) is moving northwest across the area. Overall, increased coverage of showers and thunderstorms with Lake region and western Atlantic metro seeing the highest rain chances this afternoon and evening.
1108 PM EDT Tue Sep 8 2020 A nearly stationary frontal boundary will remain stretched along the south shores of Lakes Ontario and Erie over the next few days as a strong upper level ridge expands westward into the Mid Atlantic region.
A cold front will sag slowly south across the southern terminals through daybreak, shifting winds to a northerly direction. The long advertised cold front is currently moving past Lubbock and headed our direction. In the upper levels, the upper low is still forecast to move into the Four Corners region tonight and hang out in that area through Wednesday, tapping into mid and upper level subtropical moisture, while high amounts of moisture behind and ahead of the front will provide plentiful moisture in the low levels (precipitable water values of 1. After the frontal passage, warm air advection in the low levels will continue to provide lift, resulting in potentially widespread stratiform rainfall. Due to the NAM usually handling cold fronts better, the temperature forecast continues to lean towards that model, which also happens to show the coolest temperatures for this event.
Later tonight, as the western trough digs over the Four Corners, expect an increase in large scale isentropic ascent, well depicted on the 310 and 315 K surfaces, across the southern and central Plains and the lower Missouri Valley.
Shallow cold front will continue to bring forecast and aviation headaches thru the TAF period at the E OK sites. The main weather story for tonight is the progression of the cold front and the associated showers and storms. The cold front is a little faster than most models but is still creeping southward. A pseudo cold front (outflow boundary) is currently passing through Tulsa at the moment and is pushing quickly to the southeast. Some of these storms have been strong tonight owing to modest amounts of instability and shear enhanced by the passing cold front. These aforementioned showers and storms will struggle to propagate further eastward tonight as a result of the cold front slowing and eventually stalling.
A high pressure ridge will quickly rebound on Wednesday.
340 AM EDT Wed Sep 9 2020 High pressure provides warm weather this week. The chance for rain increases this weekend, as an upper level trough brings a cold front toward the area.
Aloft, ridging is noted over the eastern CONUS with a large cut off cyclone over the Four Corners area. Perturbations emanating from the Four Corners upper cyclone will support waves of showers and storms invof the front, however, and guidance does indicate western AR remains close enough to these forcing mechanisms that isolated to scattered convection will be possible. Temperatures will remain near to slightly above average given the presence of weak upper ridging over the area.
303 AM CDT Wed Sep 9 2020 Dry weather looks to continue again today/tonight as SFC/LL high pressure and upper ridging remain in control.
The higher cirrus/cirrostratus layer of clouds appears to be dissipating/clearing off of most of the CWA at present. Although, a fresh new batch of mid/high clouds appear to be streaming into the region from the southwest, the result of a combination of earlier Colorado convection and some impressive jet-level dynamics over the northeastern quadrant of the Four Corners Region upper low. Mixed out dew points in the 20s/lower 30s this afternoon should settle in over the northern and western parts of the cwa in the upper 20s to the lower 30s after the mixing subsides this evening. Therefore, with the light winds and dew points, expect freezing to below freezing temperatures across north central sd. The period begins on Thursday with a 500 mb closed low over the four corners region with northwesterly flow aloft over the Northern Plains.
107 AM EDT Wed Sep 9 2020 A nearly stationary frontal boundary will remain stretched along the south shores of Lakes Ontario and Erie over the next few days as a strong upper level ridge expands westward into the Mid Atlantic region.
911 PM MDT Tue Sep 8 2020 The High Wind Warning and Wind Advisory have been cancelled due to winds dropping below criteria. Closed low over southeastern Utah will remain nearly stationary through the short term period. Cold air has progressed through most of the forecast area today with warmer temperatures remaining over the southern locations. Models continue to show widespread precipitation over region tonight, with the best coverage across the south, as bands of precipitation rotate around the closed low. However, higher snow levels around 9kft will limit significant snow accumulations to the higher terrain. The closed low will be near the Four Corner region by Thursday morning.
301 AM CDT Wed Sep 9 2020 A broad region of high pressure sits over the Southeast this morning, leading to clear skies apart from some high cirrus-level haze from wildfire smoke sourced from fires out West. High pressure will remain over the region through the rest of today, keeping skies clear and allowing temperatures to rise into the upper 80s to low 90s. High pressure over the Southeast really breaks down on Thursday, with easterly flow at low and mid-levels advecting in moisture from the Atlantic.
233 AM EDT Wed Sep 9 2020 Quiet weather will continue across the region today as we remain under the influence of ridging aloft.
This low will continue to weaken over the next day or so, with the western periphery of a ridge over the western Atlantic extending over the region by mid-week. At the surface, a subtle inverted trough will inch westward toward the southeast U. High pressure to the north will keep light easterly winds in place for the next several days, with an onshore flow developing with the sea breeze each afternoon.
Other- wise, the wet/messy forecast of late should persist into tomorrow with scattered SHRAs/TSRAs developing in the high PW airmass over the region.
214 AM MDT Wed Sep 9 2020 Overview: An upper level low, presently situated in eastern Utah, will meander invof the 4-Corners tonight and Wednesday. near-to-above freezing) thermodynamic profiles and a relatively homogeneous airmass in place over/upstream of the region suggest that precipitation type (RA|SN) will be rate- driven in nature. At the start of the period, an upper low is positioned just to the northwest of the region, continuing to place the High Plains under southwest flow.
343 AM CDT Wed Sep 9 2020 A deep upper-level trough over the Northern Plains will continue to dominate the weather pattern over the next few days. Although the main trough itself moves eastward today, a large cut-off upper-low over the Rockies keeps cold air firmly entrenched. At the surface a high pressure slides in from the northwest. The strong surface inversion could even cause a few isolated low spots within the Coteau des Prairies to touch freezing if skies fully clear. Dry conditions are expected with highs in the low 60s.
238 AM CDT Wed Sep 9 2020 An upper ridge will continue to build over the Mid-South today. The ridge will become centered over the region by Thursday.
We are not going to break out of this pattern until later tonight when the upper trough clears the area.
As a result, low temperatures tonight will once again drop to the low to mid 60s underneath mostly clear skies. The 5h ridge axis contributing to continued subsidence will be shifting west over AL and TN Wednesday as this drier wedge of air moves west in low levels. As the upper ridge shifts west, the inverted upper trough axis now off the Carolina coast will be shifting west through GA Wednesday night and into the lower Appalachians, including northeast AL, on Thursday. This trough is also noted at 8h and the surface and will also shift into east Alabama on Thursday afternoon.
Today through Thursday The upper low continues to rotate over the Four Corners region this morning. The low will begin to cut off from the main jet flow today. A Freeze Warning will continue for the Bighorn Basin this morning, with record low temperatures in the low to mid 20s expected across the forecast area. The upper low may sit over the Four Corners region for several days, before filling and weakening.
407 AM EDT Wed Sep 9 2020 A southerly flow around high pressure will bring dry weather and above normal temperatures through Thursday.
205 AM EDT Wed Sep 9 2020 High pressure provides warm weather this week. The chance for rain increases this weekend, as an upper level trough brings a cold front toward the area.
Steady warming is expected through the rest of the week and into the weekend as high pressure, currently centered just off the west coast, gradually inches its influence eastward.
Lows tonight will be in the lower 70s. Deep-layer subtropical ridge axis is forecast to remain oriented east-west to the north of the forecast area through the end of the week.
Otherwise, warm and dry conditions will prevail as high pressure lingers over the Ohio River Valley. As a strong upper-level low located in the Rockies cuts off late today and remains stationary into Thursday evening, ridging across the East Coast will remain a dominant feature. Areas in the ridges may observe a few stray showers early tomorrow morning.
357 AM CDT Wed Sep 9 2020 An upper level trough extends from the northern Plains to Arizona and New Mexico. This trough has increased upper lift over West Texas and southeast New Mexico. A cold front associated with this trough has pushed through the area with significantly colder temperatures and gusty winds behind it.
A warm front north of Central Indiana will weaken and slowly sag south over the next few days. strong high pressure over the northern plains will move across the Great Lakes.
With the increase in moisture there will be an increase in showers and storm activity from east to west, with the highest chances in the southeast.
Earlier this morning an upper level low was located near the Four Corners Region and an upper level disturbance was located just southeast of this upper low over New Mexico. at this time afternoon temperatures are likely to end up being less than 5 degrees warmer to what the lows will be early this morning. Some locations near the Colorado border could easily see highs today only in the upper 30s while across the remainder of western Kansas the highs will range from 40 to 45 degrees. Given the prevailing wind direction will trend towards overnight lows tonight very similar or a few degrees warmer to the lows early this morning.
Over Arkansas very weak southwesterly flow aloft was observed, possibly with some weak ridging in place over the state. Surface observations and visible satellite imagery indicated that a strong cold front was moving quickly to the south along the southern high plains, but was not making much of a southerly push on the eastern side of the front, with the front nearly stalled out over central Missouri. This leaves much of the southeastern CONUS under weak ridging aloft, which is expected to persist for the next 48 hours.
The closed upper low will be slow to evolve Wednesday into Thursday across the Four Corners region before lifting out Thursday night.
319 AM CDT Wed Sep 9 2020 The deep upper low has settled over the Four Corners region, showers continued to advect northward through the Central Plains out ahead of it. As a result of the continued rain and cloud cover, temperatures will not be much, if any, warmer than yesterday. High pressure sliding in from the west will lead to decreasing shower coverage for northwestern portions of the area by late afternoon. This trend will continue to through the overnight as the highest rain chances focus farther south and east. By Thursday evening, the upper low is forecast to start to eject out of the SW and approach the area.
155 AM EDT Wed Sep 9 2020 A nearly stationary frontal boundary will remain stretched along the south shores of Lakes Ontario and Erie over the next few days as a strong upper level ridge expands westward into the Mid Atlantic region.
Water vapour loop depicted upper low over the four corners region.
Weak SW-NE oriented trough axis north/west of I-4 this morning will continue to move westward away from the coverage warning area. Recent passage of inverted trough axis (east to west) will provide SE/ESE winds, mainly 6-12 kts, over the next 24 hours.
/issued 357 AM CDT Wed Sep 9 2020/ An upper level trough extends from the northern Plains to Arizona and New Mexico. This trough has increased upper lift over West Texas and southeast New Mexico. A cold front associated with this trough has pushed through the area with significantly colder temperatures and gusty winds behind it.
Southwest Louisiana and southeast Texas will be between the 500mb low near the Four Corners region of the western United States and the 500mb ridge across the western North Atlantic extending into the southeast U. Low to mid level moisture will continue to increase across central TX ahead of the upper level low across the western U. Dewpoints will reach the lower to mid 70s across southeast LA this afternoon. A cold front is expected to move slowly into central Texas today and into east Texas tonight before stalling across east Texas Thursday as the 500mb low across the western U. moves little and the 500mb ridge across the southeast U.
Low pressure sitting over Utah will continue to circulate cool air into the Great Basin from the north for a couple more days. Otherwise, dry conditions will continue and high pressure will bring a warming trend for the weekend. The low pressure area that brought significant wind to the northern and east central Nevada will linger near the UT/AZ border through this evening, before ejecting northeastward through Colorado on Thursday. Overnight lows will be near freezing in most areas with a slow warming during the day.
(Today and tonight) A cold front at 3 am was located from near Brownwood to just south of San Angelo to south of Mertzon.
Current WV satellite reveals an upper low over the Four Corners with southwesterly flow and multiple embedded disturbances aloft over NM into KS. At the surface, breezy northerly winds continue, with the moist conditions and widespread stratus helping to prevent any sites from dropping below freezing as of 07z. CAO and EHA automated observations have, at various times, reported UP, usually a sign of freezing drizzle or sleet. Despite the cool temperatures, guidance is unanimous is showing a slow warming trend in the lowest levels of the atmosphere.
653 AM CDT Wed Sep 9 2020 (Today and tonight) A cold front at 3 am was located from near Brownwood to just south of San Angelo to south of Mertzon.
The main question has been whether this advertised cold front will move through our region or not.
/issued 238 AM CDT Wed Sep 9 2020/ An upper ridge will continue to build over the Mid-South today. The ridge will become centered over the region by Thursday.
Warm, dry conditions will prevail today as the area remains under the influence of high pressure. A cold front stretching from approximately Erie southwestward towards Columbus will remain nearly stationary today and north of the PBZ CWA as upper-level support remains displaced from the front and mid/upper-level flow will remain nearly parallel to the boundary. Southeast flow in the low-levels on the western periphery of the Atlantic high will maintain warm and humid summer-like weather. As a strong upper-level low located in the Rockies cuts off late today and remains stationary into Thursday evening, ridging across the East Coast will remain a dominant feature. Areas in the ridges may observe a few stray showers early tomorrow morning.
High pressure will remain in place for another day to provide dry and warm temperatures across the TN Valley. High pressure over the Southeast really breaks down on Thursday, with easterly flow at low and mid-levels advecting in moisture from the Atlantic.
425 AM CDT Wed Sep 9 2020 Active weather continues through tonight as a closed upper level low and resulting trough remains over the central and southwest US. Rainfall totals around a quarter of an inch or less is expected with the highest QPF values across southwest Nebraska.
/Issued 353 AM EDT Wed Sep 9 2020/ 500mb analysis shows an inverted trough/weakness in the ridge across the CWA. The inverted trough aloft will remain nearly stationary through Thursday. The higher res models have backed off on pops today, especially west of AHN to MCN. The highest pops today should be across the far eastern portions of the CWA, with pops increasing area-wide on Thursday as the tropical wave/weak disturbance moves onshore. Highs in the upper 80s and lower 90s will prevail with upper 70s in the higher elevations. As a deep upper level trough pushes through this weekend, a surface cold front stalls across the Tennessee river valley.
CLOUDY COOL CONDITIONS WILL REMAIN TODAY WITH DECREASING RAIN Current radar trends have shown the bulk of the precip this morning vacating to the north and east with best lift across the cold front. Best lift at 500mb will be outside the forecast area, so the prospects of generating convection will be low, especially since the cooler temps will provide a stabilized atmosphere this afternoon. /issued 357 AM CDT Wed Sep 9 2020/ An upper level trough extends from the northern Plains to Arizona and New Mexico. This trough has increased upper lift over West Texas and southeast New Mexico. A cold front associated with this trough has pushed through the area with significantly colder temperatures and gusty winds behind it.
Deterministic runs maintain a quasi-stationary upper low over the Four Corners Region during the period. Given the position of the upper low, concur with deterministic runs that a frontal boundary, currently over Central Texas, will remain quasi-stationary or move slowly southward today.
Behind the front, much cooler and drier air is in place with temperatures this morning in the 40s and 50s. /issued 238 AM CDT Wed Sep 9 2020/ An upper ridge will continue to build over the Mid-South today. The ridge will become centered over the region by Thursday.
524 AM MDT Wed Sep 9 2020 Vorticity lobe rotating around the main upper low has resulted in an increase in precipitation across the area tonight. Ground temperatures remain well above freezing which will inhibit accumulations, and still expecting 1 to 3 inches of wet slushy snow in northeast Colorado, though some locally higher amounts possible. As for temperatures, they are working out as expected, with lower 30s in northeast Colorado, generally 30-33F, and near freezing in adjacent counties to the east. Tonight, expecting a decrease in precipitation coverage as upper low retrogrades a bit and settles into the Four Corners. Low temperatures currently forecast to be a few degrees warmer, low to middle 30s, with the only risk of another light freeze in western parts of Kit Carson and Cheyenne counties of northeast Colorado.
649 AM CDT Wed Sep 9 2020 Active weather continues through tonight as a closed upper level low and resulting trough remains over the central and southwest US. Rainfall totals around a quarter of an inch or less is expected with the highest QPF values across southwest Nebraska.
715 AM EDT Wed Sep 9 2020 High pressure provides warm weather this week. The chance for rain increases this weekend, as an upper level trough brings a cold front toward the area.
However, temperatures remain below freezing over a large part of the area within an anomalously cold air mass. While it may be true that most areas already saw a hard freeze last night, snow and freezing drizzle where the predominant hazards. We will begin trending warmer today as clouds break, but the upper level pattern remains influenced by an intense closed low anchored over the Four Corners region.
The deep upper low has settled over the Four Corners region, showers continued to advect northward through the Central Plains out ahead of it. As a result of the continued rain and cloud cover, temperatures will not be much, if any, warmer than yesterday. High pressure sliding in from the west will lead to decreasing shower coverage for northwestern portions of the area by late afternoon. This trend will continue to through the overnight as the highest rain chances focus farther south and east. By Thursday evening, the upper low is forecast to start to eject out of the SW and approach the area.
640 AM CDT Wed Sep 9 2020 A deep upper-level trough over the Northern Plains will continue to dominate the weather pattern over the next few days. Although the main trough itself moves eastward today, a large cut-off upper-low over the Rockies keeps cold air firmly entrenched. At the surface a high pressure slides in from the northwest. The strong surface inversion could even cause a few isolated low spots within the Coteau des Prairies to touch freezing if skies fully clear. Dry conditions are expected with highs in the low 60s.
More broken cloud coverage across the northern counties has resulted in some fluctuations with cooler temps occurring in cloud breaks. Still have the chance for few isolated showers across the far south this morning before high pressure builds farther southeast bringing drier air with it. A warmer air mass will advect in behind the upper trough tonight as the upper low cuts off over the four corners region. Coldest temps look like they will be across the lower elevations of the east tonight under the axis of the departing high.
Cooler temperatures, lower surface dew points, and a low level stratus cloud deck exist northwest of the front.
Shallow cold front will continue to bring forecast and aviation headaches thru the TAF period at the E OK, and possibly eventually the far NW AR, sites. /Issued 351 AM CDT Wed Sep 9 2020/ Synoptic cold front appears to have more or less stalled near the I-44 corridor from roughly Miami to Tulsa, then southward west of US 75 as reflected in sfc wind and dew point fields. This trend has shown up in the high-res models overnight and in the 00/06z runs of the NAM12, which only adds more uncertainty to the temperature forecast along the I-44/US 75 corridors.
Most of the CWA will see frost this morning, with several locations reaching sub-freezing temps. This cloud cover will be short-lived though, as high pressure is expected to build tonight. Freezing temps may also be possible tomorrow morning for portions of the CWA. Thursday will be a pleasant day, as high pressure remains over the CWA. Mostly sunny skies and high temps in the low to mid 60s are expected. Thursday night's low temps will be slightly warmer than tonight with only a few areas of patchy frost possible.
625 AM EDT Wed Sep 9 2020 A southerly flow around high pressure will bring dry weather and above normal temperatures through Thursday.
936 AM EDT Wed Sep 9 2020 A southerly flow around high pressure will bring dry weather and above normal temperatures through Thursday.