Aikyam-Lab/Synoptic-Bench huggingface dataset:
244 PM EDT Tue Sep 8 2020 High pressure provides very warm weather this week. Rain chances return during the weekend as an upper level trough brings a cold front through the area. An upper level ridge over the area will provide for dry weather tonight, and a very warm afternoon on Wednesday. Ridging remains overhead through the end of the week which will maintain dry conditions across most of the area.
253 PM EDT Tue Sep 8 2020 High pressure will shift farther off the Northeast coast by midweek with a stronger onshore flow pushing front and plenty of moisture back on shore.
1246 PM CDT Tue Sep 8 2020 A deep longwave trough over the Northern Plains will continue to dictate weather conditions over the next couple days.
311 PM CDT Tue Sep 8 2020 An unseasonably strong cold front extends from central Missouri into southwest Oklahoma at this time. The cold airmass behind the front is very shallow, and will only become increasingly more so with time as southerly upper level flow continues east of a very slow moving closed upper low over the four corners area. The colder air may never really make it across the higher terrain of southeast Oklahoma and northwest Arkansas.
251 PM MDT Tue Sep 8 2020 The upper low that brought rain and snow to southern MT and northern WY yesterday has now moved southward out of the area. Upper ridging and subsidence have moved in behind it, giving drier conditions under partly cloudy skies. The upper low has cut off from the jet stream and as a result it won't move much over the next few days.
High pressure is situated to the east of Middle Tennessee at the surface and aloft, so this is allowing for some return flow and gradually rising temperatures. A strong surface boundary is currently stretched across the upper midwest and into the Great Plains, and this will be our next weather-producer, but its progress is going to be hindered by the strong upper high over the eastern U.
1045 AM CDT Tue Sep 8 2020 The 12Z BRO sounding indicated a distinct drying in the lower to middle levels since yesterday. With lower rain chances and more sunshine, highs should be at least several degrees warmer today than yesterday.
100 PM MDT Tue Sep 8 2020 Upper low will cut off from the main flow today and meander over Utah and western Colorado through the short term period. Accompanying surface cold front will usher in much colder temperatures, windy conditions and a mixed bag of wintry precipitation to western parts of the area tonight and Wednesday morning. Tonight, as temperatures begin to fall into the lower 30s expecting a wintry mix in northeast Colorado and adjacent counties of northwest Kansas and southwest Nebraska.
Convection has ignited along and just south of a cold front this afternoon that is stretched out from central Missouri into central Illinois.
326 PM EDT Tue Sep 8 2020 A positively-tilted trough axis stretches southeast to near west- central Cuba. A broad and lengthy low- level trough reaches from the Yucatan northeast through south-central Florida. Deep tropical moisture straddles the low-level trough, corroborated by the 2. An unsettled pattern will persist across the Florida Keys tonight and Wednesday, consisting of an upper trough over the Gulf of Mexico, a low-level trough just to our northwest, deep tropical moisture, limited inhibition, and weak-moderate ML instability.
Region remains under the western edge of the western Atlantic upper ridge, however, weak inverted trough along the southwestern edge of the ridge lingers over the coastal plains of Georgia and the Carolinas.
259 PM EDT Tue Sep 8 2020 Upper ridging centered off the mid Atlantic Coast will continue to extend into our region, keeping us warm and dry. So, will keep things generally in the mid to upper 80s, a bit below some of the warmer guidance. Comfortable lows in the low to mid 60s look reasonable again.
1209 PM PDT Tue Sep 8 2020 Today will be cooler than average with the majority of the Inland Northwest experiencing high temperatures in the 70s.
Meanwhile, across the southeast states, sub-tropical ridging will remain in place with east/southeast flow across the Lower Mississippi Valley. Afternoon highs are expected to be in the low to mid 90s beneath partly cloudy skies. /TW/ A subtropical ridge in place through the end of the week will keep the warm airmass in place over much of the southeastern CONUS and the Gulf States.
Thus, low temps will still manage to drop into the lower to middle 60s late tonight. 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.
Updated w/ a discussion for the 09/00Z TAFs VFR conditions are ongoing across the fcst area Tues evening, and are fcst to prevail through the period as high pressure remains settled over the state.
635 PM CDT Tue Sep 8 2020 Only minor changes were made to the forecast for this update, including adjusting sky cover to better match current trends and nudging low temperatures closer to the lower end of guidance, which they were already near at some locations. Another cool night followed by a slightly warmer yet still cool day can be expected through the short term period. Wednesday then sees a shift to southwest flow which should bring slightly warmer temperatures to the region, although still well below normal.
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.
A strong storm system over Utah will bring gusty winds, much cooler temperatures and scattered showers and thunderstorms into Wednesday. As of 2 pm the cold front has moved just south of Prescott and continues to plow southward. The result will be cooler overnight temps and highs on Wednesday around 8-10 degrees cooler than this afternoon. With the upper low parking itself over Arizona/Utah border through Wednesday night there remains a threat of showers and afternoon/early evening thunderstorms east of Tucson through Wednesday night.
Cold front with numerous showers and storms has passed KBVO and on track to move past KTUL/KRVS terminals over the next few hours. /Issued 311 PM CDT Tue Sep 8 2020/ An unseasonably strong cold front extends from central Missouri into southwest Oklahoma at this time. The cold airmass behind the front is very shallow, and will only become increasingly more so with time as southerly upper level flow continues east of a very slow moving closed upper low over the four corners area. The colder air may never really make it across the higher terrain of southeast Oklahoma and northwest Arkansas.
1055 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.
348 PM MDT Tue Sep 8 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.
1036 PM EDT Tue Sep 8 2020 High pressure provides very warm weather this week. Rain chances return during the weekend as an upper level trough brings a cold front through the area. Reworked the sky grids to add a little more cloud cover for the mountains given satellite imagery of the coastal upper low. Otherwise, dry and quiet, sandwiched in between the aforementioned inverted coastal low pressure trough and the stout baroclinic zone running from the Great Lakes southward into the south plains/southwest CONUS. An upper level ridge over the area will provide for dry weather tonight, and a very warm afternoon on Wednesday. Ridging remains overhead through the end of the week which will maintain dry conditions across most of the area.
Upper ridging centered off the mid Atlantic Coast will continue to extend into our region, keeping us warm and dry. So, will keep things generally in the mid to upper 80s, a bit below some of the warmer guidance. Comfortable lows in the low to mid 60s look reasonable again.
640 PM CDT Tue Sep 8 2020 (This evening through Wednesday) Showers and thunderstorms will continue to develop along and just ahead of the cold front through this afternoon and evening. Based on current trends with the progression of the cold front, would expect the NAM12 solution to be close by Wed 12Z.
536 PM MDT Tue Sep 8 2020 Upper analysis shows a NE-SW oriented upper trough across the forecast area extending to a deep low pressure system over the four corners area in the southwestern CONUS. An area of enhanced mid-level frontogenesis continues to slide slowly southeastward across southwestern and south central South Dakota, producing a narrow band of rain, with some areas of snow along the higher terrain of the Pine Ridge in southwestern South Dakota. At the surface, dry and very cold high pressure continues to flow into the region. Dewpoints in the lower 20s over northeastern Wyoming and northwestern south Dakota point to the possibility of low temperatures well below freezing tonight so have issued a Freeze Warning for northeastern Wyoming and much of western South Dakota.
956 PM EDT Tue Sep 8 2020 Remnants of the tropical upper tropospheric trough (TUTT) across the area will continue to keep an unsettled pattern in place.
High pressure centered off the New England coast continues to wedge down east of the Appalachians, maintaining a northeasterly flow at the surface across the area. Expect a significant increase in moisture to occur later tonight as an inverted trough offshore strengthens and retrogrades closer to the coast. The increased low level moisture, extensive cloud cover, and surface winds which may not fully decouple, should result in warmer temperatures tonight.
Fortunately, cooler northern air masses dominate synoptic scale flow keeping the oppressive heat away. The main areas of concern for the next 24 hours will be the low ceilings heights, off and on rain showers through tomorrow, and the gusting winds overnight.
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.
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.
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.
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.
Patchy light freezing drizzle and maybe periods of light flurries are possible, but skies should become partly cloudy as the evening progresses. Issued a Freezing Warning for the areas that did not hit freezing temperatures last night. Early afternoon WV/IR imagery showed the upper low drifting to the south over eastern UT. Areas to the south and east received lighter snowfall mixed with freezing drizzle. These waves will provide additional lift for wintry precipitation in the form of snow and freezing drizzle, along with patchy fog.
1047 PM EDT Tue Sep 8 2020 An upper-level composite analysis this evening reveals a deep layer mean anticyclone centered over the western North Atlantic Ocean, with a sharp ridge extending westward to the mid-Atlantic States. The maximum in convective cloudiness is centered east of the low-level trough axis within the western portion of a plume of rich tropical moisture characterized by total precipitable water values well in excess of two inches.
911 PM EDT Tue Sep 8 2020 An inverted trough extends from central Florida northeastward to along the coast of north central Florida and northeastward to south of the South Carolina coastline. This trough will push slowly westward overnight, with waves of showers continuing along and west of the trough.
Due to the sporadic nature of plummeting temperatures, we are electing to not make drastic changes to the low temperature forecast and instead will handle by blending in observations and trends. The overall message of sub-freezing temperatures for most of western and central North Dakota remains on track. Only minor changes were made to the forecast for this update, including adjusting sky cover to better match current trends and nudging low temperatures closer to the lower end of guidance, which they were already near at some locations. Another cool night followed by a slightly warmer yet still cool day can be expected through the short term period. Wednesday then sees a shift to southwest flow which should bring slightly warmer temperatures to the region, although still well below normal.
Meanwhile, across the southeast states, sub-tropical ridging will remain in place with east/southeast flow across the Lower Mississippi Valley. Afternoon highs are expected to be in the low to mid 90s beneath partly cloudy skies.
1049 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.
BT The upper low that brought rain and snow to southern MT and northern WY yesterday has now moved southward out of the area. Upper ridging and subsidence have moved in behind it, giving drier conditions under partly cloudy skies. The upper low has cut off from the jet stream and as a result it won't move much over the next few days.
518 PM MDT Tue Sep 8 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.
/issued 245 PM CDT Tue Sep 8 2020/ WV imagery shows the upper trough now over eastern UT. Models dig this to the UT/AZ border by 00Z Thu, before ejecting the trough to the upper MS Valley by 18Z Sat. At the sfc, the cold front is just NW of KLUB as per area radars, and appears to be slowing as diurnal heating takes place. Speaking of, the latest HRRR develops convection along a weak dryline up against the higher terrain 19-20Z, w/development along the front 20-21Z, putting everything east of the Pecos, as well as the Stockton Plateau/lwr Trans Pecos, in a warm sector w/dewpoints mostly in the 60s.
730 PM EDT Tue Sep 8 2020 High pressure provides very warm weather this week. Rain chances return during the weekend as an upper level trough brings a cold front through the area. Reworked the sky grids to add a little more cloud cover for the mountains given satellite imagery of the coastal upper low. Otherwise, dry and quiet, sandwiched in between the aforementioned inverted coastal low pressure trough and the stout baroclinic zone running from the Great Lakes southward into the south plains/southwest CONUS. An upper level ridge over the area will provide for dry weather tonight, and a very warm afternoon on Wednesday. Ridging remains overhead through the end of the week which will maintain dry conditions across most of the area.
Otherwise the forecast remains on track with cooler temperatures tomorrow gradually warming back to normal by the end of the week.
/issued 230 PM CDT Tue Sep 8 2020/ A ridge both at the surface and aloft has provided dry and warm weather conditions to the region.
Dry and warm conditions will continue into tomorrow under high pressure. Ridging will be the dominant feature through the work week, maintaining dry conditions and warm temperature with readings approximately 10 degrees above average.
230 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.
This is due to forcing from an approaching cold front along with a moist southerly lower to mid jet. The cold front is currently moving into Val Verde county, slightly ahead of schedule. The closed mid and upper level low will remain near the Four Corners region through Thursday. Minimal instability (with an elevated freezing level) and shear (unidirectional southerly flow with little speed shear) will keep thunderstorms isolated to widely scattered in coverage and sub- severe. On Thursday, the showers and thunderstorms will focus back to the west due to weak mid and upper level ridging and slightly drier air moving in from the northeast. Temperatures for today through Thursday will be dependent on the front, turning much cooler and well below normal in its wake, though below normal elsewhere due to the extensive cloudiness and rain.
A closed low was centered in eastern UT. All three of our primary climate observations sites (KOMA, KLNK, KOFK) set records for the lowest high temperature ever recorded for the day. Surface analysis early this morning showed high pressure extending from the Dakotas and MN into eastern WY, western NE and parts of CO. Temperatures are forecast to be a bit warmer, reaching the mid 50s to around 60.
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.
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.
1101 PM CDT Tue Sep 8 2020 (This evening through Wednesday) Showers and thunderstorms will continue to develop along and just ahead of the cold front through this afternoon and evening. Based on current trends with the progression of the cold front, would expect the NAM12 solution to be close by Wed 12Z.
Temperatures are in the lower 80s across the island chain with dew points in the mid 70s. CIMSS Layer Mean Wind Analyses depict a complex, weak troughing aloft with strong, deep anticyclonic flow anchored across the western North Atlantic. The upper trough will continue to gradually weaken today but 500mb heights will rise only modestly through tomorrow (about 10-20 meters). The flow will begin to shift easterly tonight into tomorrow as the influence of the western North Atlantic ridge axis increases amid waning cyclonic flow. This will also allow temperatures to nudge back up into the lower 90s for highs and lower 80s for lows.
1049 PM MDT Tue Sep 8 2020 Upper analysis shows a NE-SW oriented upper trough across the forecast area extending to a deep low pressure system over the four corners area in the southwestern CONUS. An area of enhanced mid-level frontogenesis continues to slide slowly southeastward across southwestern and south central South Dakota, producing a narrow band of rain, with some areas of snow along the higher terrain of the Pine Ridge in southwestern South Dakota. At the surface, dry and very cold high pressure continues to flow into the region. Dewpoints in the lower 20s over northeastern Wyoming and northwestern south Dakota point to the possibility of low temperatures well below freezing tonight so have issued a Freeze Warning for northeastern Wyoming and much of western South Dakota.
Temperatures start to warm Thursday as high pressure rebuilds over the West.
Most impactful weather will come on the weekend, where we are expecting a cut-off low to move through the area and bring rain chances. Synoptically, the pattern looks pretty calm with the exception of the upper level cut-off low. Before we get to the weekend, we enjoy ridging at the surface here in the Red River Valley. Ridging will intensify in the western US, pushing a cut-off low into the northern plains region. Confidence is lower on exact track of the low and intensity, as the ensembles have taken on more divergence from each other instead of confluence.
140 AM MDT Wed Sep 9 2020 A warming and drying trend will start today as ridging begins to build in.
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.
1128 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.