Aikyam-Lab/Synoptic-Bench huggingface dataset:
Strong ridge of high pressure will build into the forecast area Thursday and Friday, resulting in a period of dry and benign weather. Highs on Thursday will struggle to climb above the lower 40s as a result, despite the clearing sky and sunshine that be in place from the late morning and afternoon hours. Winds will veer to the SE/ESE on Friday as the center of the ridge slides off to our northeast.
1106 PM CST Wed Jan 27 2021 Benign and near normal conditions will remain across the area through Thursday under high pressure. Warm advection will begin Thursday afternoon as pressures begin to fall in the High Plains with any clouds or minor weather arriving Thursday night. This is expected to take the main short wave trough and upper level low past the local area to the south.
High level clouds streaming in from low pressure to our west may prevent completely sunny skies. Water vapor imagery and the in-progress 00Z KBIS raob indicated an increase in mid-level dry air and subsidence as a ridge builds aloft, above a shallow saturated boundary layer. With the boundary layer moisture locked in place, temperatures should stay relatively warmer than the previous two nights. Warm front band of snow is slowly moving eastward, with diminishing snow rates as it progresses. If some of the lower level clouds can diminish, peaks of sunshine may come through. Friday sees continued warming, although moist southeast flow looks to continue the low cloud potential.
1117 PM EST Wed Jan 27 2021 Aviation - Light Lake Effect Snow Tonight and Thursday - Ridge Brings Quiet Weather to End the Work Week - Watching System Over The Weekend for Snow -- Light Lake Effect Snow Tonight and Thursday -- Instability is surely in place tonight and Thursday with delta t's on the order of 20C tonight.
This cold, dry airmass and NW flow around the eastern periphery of an upper ridge across the Central CONUS will result in a mostly clear sky by this afternoon as snow showers taper off across the mountains. As high pressure becomes centered over the area tonight, winds become calm with a mostly clear sky and efficient radiational cooling for cold overnight temperatures about 5 to 7 degrees below normal.
1256 AM EST Thu Jan 28 2021 A wave of low pressure will provide accumulating snow early tonight, mainly along and south of the Ohio River.
248 AM EST Thu Jan 28 2021 Low pressure has moved off the coast of the Carolinas this morning. High pressure will build in from the west today with ridging overhead through Friday.
1030 PM MST Wed Jan 27 2021 Mid and high clouds swept over the region throughout the day as a mid-level trough deepened over the eastern Pacific. Flow becomes more southwesterly tonight as the trough deepens further. Temperatures are expected to continue to moderate on Thursday and Thursday night as the eastern Pacific trough closes on the West Coast then moves ashore by Friday morning. The southwest flow continues on Friday as a deep trough moves onshore the California coast. As the trough axis moves over the Great Basin Friday evening, lift will be maximized over our forecast area.
A cold front slid through much of the region today and an upper level trough swung across the northern part of the state. High pressure at the surface will continue to move in. It will be rather chilly overnight with lows dropping into the upper 20s and lower 30s north to near freezing across the south. As upper ridging moves overhead tomorrow, sunny skies will prevail. Highs will reach the mid 40s north to the lower 50s south. /28/ Expect dry conditions Thursday night and Friday as high pressure remains in control. Frost will be possible Thursday night as lows range from the mid 20s northeast to the low 30s southwest. Highs Friday will range from the low 50s north to near 60 south.
/issued 554 PM CST Wed Jan 27 2021/ For the 28/00Z TAF period, VFR conditions will prevail this period under N/NW flow at the sfc and much of the low-mid levels. Meanwhile, some low-level stratocu to our north continues to wrap around a departing upper low entering the Ohio Valley. /Tonight through Tomorrow Night/ The Four-States region can expect a relatively quiet short-term period over the next 36 hours, thanks in part to the cold front that moved through the region today. Behind this front, strong NW flow will set up as upper level ridging builds in and moves east. Lows tonight will range from the upper 20s north, to the mid 30s south, with overnight lows tomorrow ranging in the low 30s area- wide. Highs tomorrow will also feel a little more seasonal, with highs ranging from the low to mid 50s.
Synoptic Overview: An upper level ridge, presently situated over the Rockies, will amplify as it shifts eastward over the central CONUS Tonight/Thu. Flow aloft will back to the SW-SSW Thursday night and Friday -- as a pronounced upper level trough shifts eastward ashore the Pacific Coast (Thu night) -- and an upper level low embedded therein progresses eastward from southern/ central CA into the Desert Southwest. with lows ranging from the lower teens (northeast) to lower 20s (west). At this time, expect highs ranging from the lower 40s (east-northeast) to lower-mid 50s (west-southwest).
1015 PM MST Wed Jan 27 2021 Latest analysis shows an upper ridge over the region with warmer air beginning to move in from the west. Gusty southwesterly winds will continue tonight over parts of northeastern Wyoming and over the higher terrain of the Black Hills as the southwesterly WAA continues aloft. Dry and warming weather will continue through Friday as the upper ridge remains over the area.
Makes the low to mid 50s that we have feel rather warm. Winds will slowly abate through the day Thursday as high pressure builds across the region. /issued 244 PM CST Wed Jan 27 2021/ High pressure will build in and bring a couple of cool and rather dry days.
Still have highlighted the possibility for slick spots, esp on bridges/overpasses, for the overnight hours on the HWO. In addition, these stiff winds will combine with lows in the lower 20s to create daybreak wind chills in the teens. Lows Thursday night are forecast in the low to mid 20s, however much will depend on whether winds become calm where the ground is snow-covered.
JB Chattanooga Airport, TN 30 44 26 49 29 / 10 0 0 0 0 Knoxville McGhee Tyson Airport, TN 29 38 22 44 26 / 80 10 0 0 0 Oak Ridge, TN 27 39 21 44 26 / 60 0 0 0 0 Tri Cities Airport, TN 26 34 18 40 20 / 70 10 0 0 0 TN.
So far, only light snow has been seen in the northeast OR mountains while virga can be observed across portions of the Lower Columbia Basin. Meanwhile, this low pressure system will continue to open into an upper level trough while digging further south into northern CA, placing the forecast area under a southerly flow aloft. Late Thursday, upper level trough will begin to move into northern CA while a transient ridge moves across southern BC and northern WA, placing the forecast area under a weak Rex block pattern.
1140 PM CST Wed Jan 27 2021 Clouds will continue to clear in the wake of the departing upper trof this evening. However, there is potential for freezing fog later this evening into early Thursday morning in the developing south-southeast return flow over the snow cover in central and parts of southeast Kansas. Otherwise, an upper ridge will build over the area Thursday into Friday with the milder return southerly low level flow sending temperatures back above seasonal climo except over the lingering snow cover.
Cold high pressure situated over the northern Mississippi Valley region and eastern Plains (~1040mb magnitude) was building southward and bringing colder air across this Deep South. But blustery NW-N winds of 15-25 mph, and higher gusts was producing wind chill values into the low/mid 20s. Most short term model guidance has the stratus breaking up during the course of today, as drier air mixes in and the surface cyclone moves further offshore. As such, highs will only warm into the lower 40s, colder than normal highs of around 52. High pressure situated over the region along with generally clear skies, and light winds, will produce chilly conditions Thursday night. Low temperatures by daybreak Friday will range in the lower 20s. Slightly warmer conditions under sunny skies are forecast Fri, with highs near 50.
Around or shorty after 12Z, skies will clear and VFR will develop as dry high pressure continues to move into the region.
Winds of less than 5 mph and dewpoints in the upper 20s to near 30 will allow temperatures to reach freezing in parts of the Hill Country and possibly a few low lying spots along the Escarpment by sunrise this morning. Winds of 5 to 10 mph will keep temperatures a bit above freezing elsewhere. Cirrus clouds move through the upper level ridging that will persist over our area. As surface ridging slides across our area today, southeasterly flow returns out west. Surface ridging drifts to the east Friday, allowing southeasterly flow to return to all areas. Low level moisture returns to the Rio Grande Plains and Edwards Plateau Friday morning bringing low clouds to those areas with some patchy fog possible in the higher terrain of the Edwards Plateau.
Upper level flow will continue to become increasingly northwest between a departing trough to our east and a building ridge to the west. This will lead to building high pressure at the surface. The center of the high will remain to our northwest tonight resulting in continued strong cold air advection with gusty northwest to north winds. The clouds and wind will keep temps from getting as low as they could in this pattern, however cold air advection will allow temps to fall into the low to mid 30s northwest of I-65 to upper 30s southeast of I-65. Dry and cold conditions continue through Thursday as high pressure continues to build into the area. Increasing subsidence will clear out any remaining clouds during the morning, however cold air advection will continue and highs will struggle to reach the low to mid 50s.
146 AM MST Thu Jan 28 2021 Water vapor shows large upper ridge building from the Rockies into the Plains, with upper trof digging offshore the west coast. At the surface, low pressure resides over northeast WY with warm front extending eastward across the Black Hill and into south central SD. Warm front will nudge northeast today, resulting in highs rising into the 40s in many areas (a little cooler in northwest SD). Upper ridge maintains control through Friday, with highs a few degrees warmer.
Lake-enhanced snow showers are possible through Friday mainly north of I 80 and in the ridges. A low pressure system may bring widespread snow late this weekend. 1 to 2 inches of accumulation is expected across the I-80 corridor and the PA ridges, with generally less than an inch elsewhere.
Area of cloud cover currently running from the eastern Dakotas across much of central and southern Minnesota looks to stick around to a large extent as it shifts east tonight into early Thursday, then we'll see an increase in mid-high clouds later Thursday into Thursday night with warm advection and upstream clouds spilling down the ridge. Upper-level ridging over the upper Midwest will begin to build into the Great Lakes region on Friday.
240 AM CST Thu Jan 28 2021 High pressure will move across the area today through Friday, resulting in dry weather. Went a little cooler than NBM for highs after coordinating with other WFO's, though not much given return sunshine should help to offset this concern.
A Strong Cold Front Will Cross the Area Overnight. A cold front is moving through northern FL. Tight northerly pressure gradient expected between deepening low off the US East coast and strong high pressure building south from the upper midwest. Dry and cool as afternoon highs barely reach the low 60s across the north, and mid to upper 60s from Melbourne south. A period of IFR/MVFR CIGs expected to spread southward overnight ahead of the cold front. Low pressure will develop off the Carolina coast overnight and deepen rapidly, sweeping a cold front across the waters.
The model blend also predicts lows in the low single digits in the valleys of swrn and scntl Nebraska which would send humidity to 100 percent. Arctic high pressure has built all the way into the Midsouth and the south winds developing tonight through Thursday night across wrn and ncntl Nebraska will recirculate this cold air north at the sfc. This warmer air will resist mixing to the sfc across all of the region except across the Panhandle and the western Sandhills where highs in the 40s are expected Thursday.
Through the evening hours, the moisture stream has started to shift more north as the upper level trough tilts to a neutral position off the California Coast. By morning, there may be a lull in the precipitation in the lower elevations with more scattered activity than continuous bands. Cold air seems to be holding firm in the lower elevation of the Owens Valley which is a bit of surprise and delayed the transition over to rain. This transition east is due to the upper level trough with this system dropping south and rotating inland and through the area within the larger long-wave trough over the area.
Arctic high pressure will build gradually east/southeast through Ontario and maintain a cold airmass across the area with generally quiet weather conditions.
159 AM MST Thu Jan 28 2021 Upper ridge will move to the east this morning. SW flow aloft is expected today and Friday which will continue to bring warmer air aloft into the region.
Dry and cool conditions will continue for the rest of the work week with warmer conditions and rain over the weekend. Precipitation associated with the quick moving upper trough is pushing east into Middle Tennessee. Should start to see some clearing after midnight according to the low level RH fields but would not be surprised to clouds hang in for most of the night. The first half looks pretty wet with low pressure tracking from the southern plains to the Mid-MS Valley and the associated cold front sweeping across the Mid-South.
700 millibar temperatures are expected to climb to around -2 deg C beneath ridging aloft. Friday will bring one more day of breezy yet quiet weather to the High Plains and adjacent High Terrain ahead of the next pattern change.
Low-level theta-e advection ensues today downstream of the amplifying southwestern CONUS trough. Despite the low clouds on Friday, temperatures should moderate further, with highs mostly from 25 to 30 degrees. On the temperature front expect warmer temperatures above climatological averages this period.
254 AM CST Thu Jan 28 2021 Surface ridging slowly progressing across the Upper Midwest will provide quiet weather through tonight. Some mid/high clouds associated with warm advection will spill eastward across the area into today around a mid-level ridge.
Tonight will likely be another chilly night with the high pressure sliding further east across southern Canada. High pressure begins sliding off to the east tomorrow and winds turn to out of the southeast with slightly warmer temperatures entering the region.
/issued 226 PM CST Wed Jan 27 2021/ An upper level trough/low is over Missouri and Illinois and another upper trough is moving onto the west coast. An upper ridge begins to build over the central part of the country on Thursday with southerly winds returning to the area. The upper trough to the west moves closer to the region on Friday with southwest winds aloft.
316 AM EST Thu Jan 28 2021 Expansive stratus deck has filled in nicely across SE MI early this morning which have even produced periods of flurries as an expansive high pressure system slowly fills in across Ontario and locations south into the Midwest and Great Lakes region. Ongoing cold air advection and cloud cover will support daytime highs in the low to mid 20s. Overnight lows to drop into the low to mid teens with associated wind chills in the low single digits. Seasonally strong high pressure system (~1032 mb, 90th climatological percentile per NAEFS/ECMWF climatology) will then hold over Ontario and extend south into the Great Lakes through the end of the week and will bring about a period of dry weather and slightly below normal temperatures.
A cold air mass will settle over Alabama today and Friday on the west side of an upper level trof over the eastern United States.
505 AM CST Thu Jan 28 2021 Surface ridging slowly progressing across the Upper Midwest will provide quiet weather through tonight. Some mid/high clouds associated with warm advection will spill eastward across the area into today around a mid-level ridge.
612 AM EST Thu Jan 28 2021 High pressure will build into the area today and Friday. A low pressure system moving through the Ohio Valley will bring rain and snow to the region this weekend. The high pressure will remain across the region through the day on Friday.
Most of the guidance keeps temps cooler than the upper 20s to low 30s that we have in the forecast.
439 AM CST Thu Jan 28 2021 Latest nighttime microphysics is showing that the clearing of the low clouds has stopped across the CWA with stratus south of the Missouri River and west of the Mississippi River. Expect dry weather through tomorrow as an upper ridge moves across the area. Expect a sunny day, but with fresh snow cover, a cold start to the morning, and light southeasterly winds, expect highs to only climb into the low-mid 30s.
The high will allow for CAA near the surface and afternoon temperatures today will struggle to get out of the 60s.
518 AM CST Thu Jan 28 2021 A thin stratus deck remains over the forecast area early this morning with temperatures in the lower and mid 20s and light easterly winds. As high pressure shifts east of Missouri during the day, winds will become more southerly. A few locations on the higher parts of the Ozarks Plateau where thicker snowpack resides may only rise into the mid 30s. Increasing south winds tonight will help hold overnight lows a few degrees warmer than early this morning, ranging between the mid 20s over the east to near 30 degrees along the KS and OK borders.
Tonight, expect clear skies and calm winds as the high slowly shifts east into the Tennessee River Valley. With lows ranging from the lower 20s near the Tennessee River to upper 20s across Eastern Arkansas.
420 AM MST Thu Jan 28 2021 Water vapor shows large upper ridge building from the Rockies into the Plains, with upper trof digging offshore the west coast. At the surface, low pressure resides over northeast WY with warm front extending eastward across the Black Hill and into south central SD. Warm front will nudge northeast today, resulting in highs rising into the 40s in many areas (a little cooler in northwest SD). Upper ridge maintains control through Friday, with highs a few degrees warmer.
A deep mid/upper level trough will move on shore along the West Coast by this evening. Temperatures tonight will be warmer than last night, with light winds and overnight lows in the 30s.
Thus, the high temp fcst today wl be a challenge. However, the last few runs of the HRRR keep the low clouds in place most of today ovr much the FA. Skies are expected to clear out tngt, as high pres ridge passes acrs the FA.
It's still a chilly start to the day, with temperatures ranging from the low 20s to low 30s across the region. Today will begin a warming trend for the next few days as temperatures will rise to near normal today as upper ridging begins to build in from the west.
327 AM MST Thu Jan 28 2021 An anomalously strong low pressure is located just off the coast of the Pacific Northwest. Weak lift out ahead of the low pressure is clipping the northern half of the area this morning. Given some areas have fresh snow and these widespread clouds decided to go lower than most of the guidance for highs today especially along the highway 160 corridor. The southwest flow continues tomorrow as a deep trough moves onshore the California coast. As the trough axis moves over the Great Basin in the evening, lift will be maximized over our forecast area.
High temperatures in the 30s and 40s are expected across the High Plains and adjacent High Terrain. Quiet weather under a dry southwesterly flow continues into Friday as a deep upper level low continues to effect the Pacific coastline.
A substantial trough aloft with almost no moisture will be zipping toward NY from James Bay through the day with an increase in SHSN/flurries from this feature occurring after dark tonight.
229 AM MST Thu Jan 28 2021 Satellite imagery shows a ridge building over the northern high plains in advance of a deep trof along the Pacific coast. As the Pacific coast trof moves slowly into the Great Basin, the southwest flow aloft will continue to produce periods of high clouds over our region, and some snow along southwest aspects of the Beartooth/Absarokas, but the remainder of our cwa will be dry today thru Friday morning. Most places will see highs in the low-mid 40s today and mid-upper 40s Friday, but lack of stronger downslope flow and cloud cover should keep some areas cooler than their potential.
314 AM CST Thu Jan 28 2021 A thin stratus deck remains over the forecast area early this morning with temperatures in the lower and mid 20s and light easterly winds. As high pressure shifts east of Missouri during the day, winds will become more southerly. A few locations on the higher parts of the Ozarks Plateau where thicker snowpack resides may only rise into the mid 30s. Increasing south winds tonight will help hold overnight lows a few degrees warmer than early this morning, ranging between the mid 20s over the east to near 30 degrees along the KS and OK borders.
Most stay in the lower to mid 20s, with upper 20s to mid 30s west of the James River into south central SD. Upper level ridge has worked its way into our area, and continues through tonight. Brisk winds and cooler temps across the area keep wind chills below zero this morning, and in the single digits above for most today. More of the same on tap for Friday, with the upper ridge over the region continuing to usher in robust WAA and strong southerly surface flow. Expect highs in the upper 20s to mid 30s (cooler in the east and warmest for south central SD.
445 AM CST Thu Jan 28 2021 High pressure will move across the area today through Friday, resulting in dry weather. Went a little cooler than NBM for highs after coordinating with other WFO's, though not much given return sunshine should help to offset this concern.
448 AM CST Thu Jan 28 2021 Cold high pressure will continue to build into the area bringing cooler and drier conditions today with highs only rebounding into the middle 50s. Upper level ridge over the central conus will drift eastward throughout the rest of the week. Clear skies and calming winds will alow for near or below freezing conditions on Friday morning.
524 AM CST Thu Jan 28 2021 Latest nighttime microphysics is showing that the clearing of the low clouds has stopped across the CWA with stratus south of the Missouri River and west of the Mississippi River. Expect dry weather through tomorrow as an upper ridge moves across the area. Expect a sunny day, but with fresh snow cover, a cold start to the morning, and light southeasterly winds, expect highs to only climb into the low-mid 30s.
Gusty winds and clouds have already affected temperatures overnight,where it has been warmer than expected. Right now temps are nearly 5 degrees warmer than expected, not sure how much cold advection will beat out the warmer start. Lowered afternoon highs along I-20 from the lower 50's about 1-2 degrees. Looking for generally clear skies tonight with the ridge getting closer and much lighter winds.
/issued 324 AM CST Thu Jan 28 2021/ SHORT TERM (Now through Friday): Mid level ridging builds across the central CONUS as a strong storm system dives south along the California coast and another system drops into New England. Southeasterly flow increases through the day on Friday as high pressure heads east and low pressure works through the Rockies. A few more peeks of sunshine and increased southerly flow could help nudge highs back into the low to mid 70s to end the work week.