Aikyam-Lab/Synoptic-Bench huggingface dataset:
There has been little change in the large scale pattern with high pressure in control at the surface and mid level ridging upstream. As high pressure begins to shift east on Sunday, winds will veer to east and southeast, also allowing dew points to increase. Continued moisture return will add a little more depth to the low cloud layer Sunday night.
A weak warm front over Western Washington will lift north of the area today, as an upper ridge moves into the Pacific Northwest.
1105 AM MST Sat Jan 13 2018 Near Omega block setup over NOAM will eventually breakdown in the period as massive ridging over the western Atlantic subsides. Arctic trough over the eastern CONUS will linger a few more days with backside impulses supporting a wavering baroclinic zone over the region. Favored NW flow upslope areas in the northern Black Hills can expect 2-4 inches of snow today, with the higher amounts generally above 6 kft. As the upper wave exits and ice prod layer is lost aloft, upslope forcing may support a period of freezing drizzle over parts of the northern BH late tonight into Sunday morning, esp as WAA revs up ahead of the next wave. Temps will vary sig across the FA today as WAA spreads into and remains confined to the higher terrain of NE WY and BH.
333 PM CST Sat Jan 13 2018 Forecast highlights in the short term period will be a brief period of 'milder' weather tonight into tomorrow, followed by another Arctic cold frontal passage on Sunday. The low clouds will move into south central ND momentarily for several hours tonight as noted via sat imagery and high res boundary layer RH. Strong embedded S/WV will pivot around a large upper level low near the Hudson Bay, moving south-southeast across the southern Canadian prairie provinces tonight then across the Northern Plains on Sunday. This will drive another Arctic cold front through the region, resulting in gusty northwest winds and falling temperatures Sunday afternoon. Also at this time it appears the period where we will see the combination of snow/patchy blowing snow/gusty winds on the leading edge of the cold front/pressure rises will be relatively short.
1249 PM EST Sat Jan 13 2018 High pressure will begin to build toward the region from the west today. The high will then settle over the region tonight, then moving east on Sunday.
309 PM EST Sat Jan 13 2018 Water Vapor imagery highlights a broad long wave trough complex across the continental United States. As this short wave rounds the base of the trough, the meat of the cold front will drive southeast through the Gulf of Mexico and blast through the Keys.
314 PM CST Sat Jan 13 2018 Another chilly day is well underway across eastern Oklahoma and western Arkansas as high pressure prevails. Any snow that does fall shouldn't last long as temperatures expected to be warmer on Sunday Afternoon than they have been for the past couple of days with highs ranging from the mid 30s to mid 40s.
228 PM EST Sat Jan 13 2018 High pressure builds into the region tonight and Sunday.
330 PM EST Sat Jan 13 2018 Low pressure will exit into the Maritimes. High pressure will build in from the west tonight and Sunday and crest over the area Sunday night. Will be issuing a special wx statement in it's place to highlight freezing of standing water and slippery conditions.
1103 AM MST Sat Jan 13 2018 Adjusted temps on plains downward a bit given the low clouds still on the plains in some spots. The HRRR is showing the low stratus dissipating thru the morning hours but is showing it staying around the KPUB area the longest and finally has it dissipating between 18 and 19Z. Temp forecast for today over the southeast plains is a little challenging and think that leaning toward the cooler model guidance values is the way to go.
Upper ridge centered near the west coast will continue to approach southeast Oregon and southwest Idaho today. Moisture residing within a northwest flow, which is preceding the ridge, will provide our northern areas with partly to mostly cloudy skies today.
949 AM MST Sat Jan 13 2018 High pressure over the western U. highly amplified ridge is still forecast to be aligned over far western NOAM with ginormous troughs upstream and downstream.
1035 AM MST Sat Jan 13 2018 18Z TAF CYCLE Dry nw flow aloft with sfc lee trough.
316 PM CST Sat Jan 13 2018 This afternoon, an upper longwave TROF existed over eastern North America with a upper longwave RIDGE in the west, yielding NW flow aloft for our region. At the surface, the latest bitter cold air intrusion is represented by a large area of high pressure, centered in Iowa, with northerly winds for our region. Temperatures across our region ranged from the upper teens to the lower 20s.
By Sunday, the next trough and surface cold front will push through, perhaps with a little light snow in some areas.
445 AM EST Wed Feb 21 2018 A cold front will move across the area this morning bringing widespread showers and cooler temperatures. Low pressure tracking just south of the region tonight into Thursday will result in more widespread precipitation. Cold front has entered the far northwest part of the forecast area. The other concern is that temperatures north of I-70 will likely fall to or just below freezing. This would result in a period of freezing rain. Forecast lows are a multi-model blend while highs leaned towards cooler guidance.
Temperatures continue to quickly fall this evening across the area, with the western 2/3 or so of the forecast area already below freezing. Cold air will slowly filter into the area overnight with temperatures steadily falling below freezing from west to east. Depending on how long the rain lasts across far SE WI and how quickly the cold air can make it that far east, there may be a brief period of freezing rain in far SE WI around 06Z. Forecast confidence is high: High pressure will bring some sunshine and colder temperatures on Wednesday, with highs a couple degrees below normal.
Don't expect that to last much into the daylight hours as a ridge moves in. The ridge will result in clearing skies today and mostly clear skies tonight. Nam shows a 500 mb trough in the western U. with a ridge in the sern U. The trough moves moves into the Rockies and northern plains 12z Sat. Still looks like there could be a wintry mix of pcpn on Fri morning with the highest pops then. In the extended, GFS and ECMWF show a 500 mb trough in the Rockies and northern plains 12z Sat. This trough heads northeast into the upper Great Lakes 12z Sun. More upper troughing moves in for 12z Mon. Troughing moves into the western U. on Tue and Wed and pushes up a ridge into the ern U.
Strong high pressure will remain east northeast of the region through the period. Mainly dry conditions will prevail today due to the strong ridge just east northeast of the area, but there is around a 10% chance of a shower across southeast Georgia this afternoon. Highs today will be near records once again, with temperatures in the low to mid 80s inland and mid to upper 70s along the coast. Overnight lows will be mild in the low to mid 60s.
other issue is remaining standing roads in low areas, along with freezing of the water with the colder temperatures.
404 AM EST Wed Feb 21 2018 Rain returns today with the passage of a cold front. Cold front will cross most of the area this morning, clearing the southeastern ridge by late this afternoon. The cold front will stall just to the south of the area tonight, allowing additional moisture to get pumped into the region in the southwest flow aloft. Models are still showing some disagreement in the temperature structure, and have continued mention of snow and freezing rain, which is dependent on whether the low-level cold air manages to drive far enough to the south.
These showers and storms are training near the vicinity of a cold front, which is located from north of KPSN, to KTYR, to just west of KTXK, to near KHOT. /issued 554 PM CST Tue Feb 20 2018/ For the 21/00z TAFs, convection is likely to affect all TAF sites this period as a strong cold front gradually move into and across the area.
Remaining TAF airports are expected to drop to the lower MVFR or high IFR category by 12z. Most of the moisture is in the lower 8,000 feet of the sounding below a 2-3C inversion. Freezing level this evening is just below 14,000 feet with the -20C level near 25,000 feet. Shear is fairly limited in the lower levels. /issued 356 PM CST Tue Feb 20 2018/ Steady state onshore flow persisting on what still appears to be an out-of-season Bermuda ridge pattern. Southwesterly flow aloft will slow down advance of air masses a bit until cut-off low feature in the desert southwest ejects northeast this weekend.
252 AM CST Wed Feb 21 2018 Skies are clearing from the northwest with some high clouds as high pressure moves in. Area temperatures have dropped into the mid teens far NW to the lower 20s in the southwest. However, as warmer air works into the area the snow will mix with freezing drizzle and then eventually drizzle for areas south of highway 30.
139 AM EST Wed Feb 21 2018 After another mild night, a cold front crosses the Middle Ohio Valley today. A mild morning expected today, with southerly flow ahead of an approaching cold front. The cold front will move through from west to east this afternoon and evening. Showers, heavy at times, will continue on Thursday as wave of low pressure moves northeast through the area along stalled frontal boundary.
321 AM CST Wed Feb 21 2018 Currently cold front and leading edge of heavier convection is snaking it's way from northwest Tennessee back into the northern Memphis metro and east central Arkansas. to the low 70s in the south and east.
There should be a brief period with activity waning during mid morning WED before redevelopment due to an approaching cold front.
Cloud cover should help low temperatures stay warmer than they were last night, but still below normal. Lower valleys of southwest Idaho could see a snow shower, especially in the lower Treasure Valley, but generally precipitation will focus over southeast Oregon and mountains of southwest Idaho.
1217 AM EST Wed Feb 21 2018 Rain returns today with the passage of a cold front. Cold front will cross most of the area this morning, clearing the southeastern ridge by late this afternoon. The cold front will stall just to the south of the area tonight, allowing additional moisture to get pumped into the region in the southwest flow aloft. Models are still showing some disagreement in the temperature structure, and have continued mention of snow and freezing rain, which is dependent on whether the low-level cold air manages to drive far enough to the south.
/issued 825 PM EST Tue Feb 20 2018/ Significant ridging in place will continue our record breaking temperatures (see climate section below) with widespread upper 80s tomorrow and maybe even a couple of Although ample low level moisture exists and some clearing will occur, it appears as though boundary layer winds may be too strong for widespread fog development and low stratus will prevail in the morning hours. Strong ridge of high pressure continues to dominate our region with prevailing easterly winds and no rain chances. Meanwhile, the low temperature of 73 degrees this morning at Tampa International would be a monthly record high minimum if it does not drop lower before midnight tonight.
TEC Previous Discussion: Deep trough over the West with an upper ridge off the East coast will continue with some flattening. Mid and high level clouds will move through tonight and early Wednesday with a weak cold front approaching the area. Then NE Montana will be sandwiched between a system over central Canada Thursday Night while low pressure spreads precip well to our east.
A strong upper level ridge will remain in place just to our east and it will strengthen through the middle of the week. Both of the GFS and the ECMWF continue to show the upper level ridge beginning to weaken towards the end of the week and into this weekend. The lower ridge axis will also shift southward creating more of a southeasterly flow into the upcoming weekend. Temperatures will continue to be in the low to mid 80s during the day, with overnight lows in the 60s over the interior and Gulf and low 70s along the east coast. A strong ridge of high pressure will continue to dominate the weather pattern over the local waters through the remainder of the week and into the upcoming weekend.
/Issued 626 PM CST Tue Feb 20 2018/ For the 00Z TAFs, the sfc cold front is well south of the forecast area. Light snow looks to be the primary precipitation type across the northwest half of the forecast area on Wednesday, with sleet and freezing rain being more likely across the southeast half. Another jet streak and vorticity maximum emerges from western trof on Thursday, with light freezing rain possible during the morning.
The overall synoptic pattern will remain stagnant through the period, as the region will remain situated on the western periphery of deep layer high pressure. Deep layer ridging will prevail through the short term with little to no chance for measurable rain.
349 AM CST Wed Feb 21 2018 Cloud cover along with surface ridging to our west/persistent northeasterly surface winds will keep the shallow cold air in place today, with much of eastern OK and far northwest AR remaining near or below freezing. Morning precipitation will be mainly confined to areas near or a little above freezing (far southeast OK/western AR), although precipitation is expected to lift back north through western/central OK later this morning and into portions of eastern OK during the afternoon and into the evening hours. RAP/NAM soundings suggest a mix of freezing rain and some sleet, with the greatest accumulations generally along and west of a McAlester to Vinita line.
POPS fairly similar this afternoon and Thursday, but the battle between the front and the southeastern ridge makes me a bit suspicious that Thursday may be a bit drier than forecast, as the NAM QPF fields suggest.
1134 PM CST Tue Feb 20 2018 WV imagery was showing the upstream longwave trof has nudged a bit to the east since yesterday and currently extends from about central Canada to Baja. However, models are in pretty good agreement large scale pattern will become stagnant with the upper trof moving little the next several days. Thursday morning, precip type becomes problematic as MaxT aloft push just above freezing. And with BUFKIT showing feeder-seeder process waning along with boundary layer temps below freezing, dominate precip type will likely be freezing drizzle by late morning and continuing through the afternoon. Light freezing drizzle appears to still be possible Thursday evening.
Also I added some patchy freezing fog to some of the more sheltered valleys and areas near bodies of water. Cote' 06Z TAFS: And upper trough sags by and a boundary near SE WA/lower ID will bring the potential for MVFR cigs near PUW/LWS and a few snow showers near LWS, possibly PUW through the early overnight before clearing.
20Z regional radars show the last bit of rain/freezing rain moving east of the forecast area. GFS/NAM thermal/moisture profiles suggest initial p-type will be snow, but decreasing cloud ice from south to north and increasing maximum temperatures aloft Thursday night should allow precipitation to change over to a wintry mix or predominately freezing rain.
On Thursday, increasing southwest winds are forecast ahead of an approaching cold front.
Given thermal profiles aren't entirely saturated in the key layer for ice crystal formation, at this point there appears to be the potential for some freezing rain/drizzle again with this event. The higher chances at this point look to be from south central MN into west central WI, similar to where we had icing issues with this last event.
Wind Chill Advisory working out for those counties and its close enough to continue across the rest of the highlited area.
Strong mid level ridge (595-596 dm) centered off the mid Atlc coast will produce subsident drying and reduce the precipitable water values compared to yesterday. In the lower levels, E/SE flow will continue with breezy conditions along the coast. Persistent onshore flow tonight will keep coastal communities warm with lows in the low 70s, which is 15-20 degrees above the seasonal average. Deep layer ridge aloft will continue to extend across Florida, with ridge axis at the surface remaining north of the area and providing an elevated SE flow in the lower levels.
Similar to last night, brief periods of moderate to heavy freezing rain and/or sleet can't be ruled out Latest radar mosaic shows a northward shift of precipitation across north Texas with heavier precipitation now approaching the Red River.
319 AM CST Wed Feb 21 2018 High pressure centered over the state will gradually drift east today with low level flow remaining westerly. High pressure continues east overnight and flow becomes southerly ahead of the next system. Energy aloft will continue to dive south along the west coast, thus keeping a western conus trof pretty much in place. Pcpn type should favor snow, but patchy freezing drizzle also looks possible mainly before and after the main event has occurred.
352 AM CST Wed Feb 21 2018 Very benign short-term portion of the forecast with arctic high pressure moving across the region and upper level flow transitions from zonal to slightly southwesterly with a much drier atmosphere. Surface analysis shows the center of high pressure over the Dakotas and this high pressure airmass is expected to shift easterly over southern Minnesota and into the Great Lakes through Thursday morning. While the high pressure area shifts off to the east tonight, a weak cold front will drop in from the northwest.
345 AM EST Wed Feb 21 2018 TODAY THROUGH THURSDAY: South Florida weather will continue to be driven by the large upper level ridge now centered to our northeast off the coast of the Carolinas. The ridge is forecast to strengthen over the next 24 hours as it becomes more east west oriented across Florida. The eastern side of the region will hold a little closer to normal in the low to mid 80s.
/issued 352 PM CST Tue Feb 20 2018/ The deep trough to our west continues to dig into northern Mexico this afternoon. Strong SSW flow aloft downstream of this trough is pumping abundant mid/upper-level moisture across the Southern Plains and Midwest. The cold front attendant to the Great Lakes cyclone will move south into the CWA late tonight and slide slowly south throughout the day. By Thursday morning, the cold front is expected to be located just south of the CWA which will keep the highest rain chances confined to north MS.
325 AM CST Wed Feb 21 2018 A strong high pressure at the surface was centered over Nebraska early this morning, with a ridge extending northeast to over northern Minnesota. Aloft, there is a trough axis out over the Rockies with ridging east, and a strong upper level jet extending from Texas to the western Great Lakes. Temperatures to remain below normal today and tonight with the ridge overhead and fresh snow cover, with the airmass offsetting the late February sunshine. Tonight the ridge and clear skies is going to make for good radiational cooling conditions.
The higher probabilities given the prevailing wind will be over upper Keys, and this is reflected in the the gridded forecasts.
848 PM MDT Mon Mar 26 2018 Upper trough was clearing the state with clouds decreasing. Upper trough gradually working its way east across the region. Temperatures at 850mb remain well above freezing through most of the night with some instability indicated in the progs.
Late afternoon satellite pictures did show some clearing in the east and this did allow temperatures to remain warmer this afternoon and early evening. This is likely being aided by downslope flow coming across the higher terrain. As a warm front approaches from the west clouds will thicken back up tonight and there will be a chance for showers. A better chance of showers will occur Tuesday night as low pressure moves from the mid MS valley into the OH valley and a cold front approaches the area. A broad trough will gradually move from the Mississippi Valley to the Eastern Seaboard.
624 PM CDT Mon Mar 26 2018 Satellite loops showing a good plume of moisture coming into the southern Rockies and central plains at 19Z, around the base of the western trough moving across southern California. At the surface, low pressure was located over south central Kansas with an inverted trough extending into southeastern Nebraska and a warm front into central Missouri. A few showers will continue this evening mainly east of the inverted trough over southwest Iowa. Models have the front pushing south towards Oklahoma this evening as the low lifts northeast into north central Missouri and a northern stream trough advances into the northern plains.
653 PM CDT Mon Mar 26 2018 Satellite imagery shows deep trough in western US and southwest flow from NM into IA/MO over deep moisture. Convection in isentropic lift over warm front moving over eastern MO and central IL through day today. Toward morning, cold front to be moving into central IL, with the heavy pcpn focus becoming more focused over the southeast parts of CWA, gradually weakening in the northwest 1/2. High pressure begins to build into the northwest sections.
/issued 349 PM CDT Mon Mar 26 2018/ A deep trough continues to spin over the southwest CONUS with a downstream ridge extending from the Gulf of Mexico into western New England. An attendant warm front has lifted north across the area with gusty south to southeast winds highlighting the warm sector environment across the Mid-South.
LZK, OHX and JAN 00Z soundings showed the lower atmosphere capped with respect to deep convection. /issued 349 PM CDT Mon Mar 26 2018/ A deep trough continues to spin over the southwest CONUS with a downstream ridge extending from the Gulf of Mexico into western New England. An attendant warm front has lifted north across the area with gusty south to southeast winds highlighting the warm sector environment across the Mid-South.
Convection will develop across Oklahoma and Texas along and ahead of a cold front on Tuesday.
944 PM CDT Mon Mar 26 2018 Shower and thunderstorm coverage continues to increase this evening within axis of anomalously high moisture east of upper low moving through the Desert Southwest. Flight conditions will deteriorate overnight into Tuesday morning as a cold front moves south across the area, and the coverage and intensity of rain and thunderstorms increases. /Issued 349 PM CDT Mon Mar 26 2018/ Afternoon water vapor imagery shows closed upper low over southern CA, with a broad and moist southwesterly flow aloft across the southern and central Plains. Latest mesoanalysis places cold front into northwest Oklahoma, with gusty northwest winds from Medford to Seiling, with a dryline mixing into southwest Oklahoma southwest into Texas.
815 PM EDT Mon Mar 26 2018 Backdoor cold front pushed across the region late this afternoon with a surge of east to northeast winds which across the forecast area which persists this evening. High pressure will build down the eastern seaboard and over Florida in the wake of the front with partly cloudy skies and mild dry conditions expected through mid week. High temperatures will run in the low to mid 80s over the next couple of days.
Even areas with snow cover have jumped up into the lower to middle 40s. Satellite imagery shows deep trough in western US and southwest flow from NM into IA/MO over deep moisture. Convection in isentropic lift over warm front moving over eastern MO and central IL through day today. Toward morning, cold front to be moving into central IL, with the heavy pcpn focus becoming more focused over the southeast parts of CWA, gradually weakening in the northwest 1/2. High pressure begins to build into the northwest sections.