Aikyam-Lab/Synoptic-Bench huggingface dataset:
Early this morning, a compact upper level low as seen in water vapor channels lifts northeast through the Ohio Valley. Weak mid/upper level energy rotating around the southeastern periphery of the low along with weak isentropic ascent in the 305-300K layer should be enough for isolated to scattered showers especially in the higher terrain through Sunday. Colder air in the high terrain could allow for some light snow and any amounts will remain light with a dusting to a couple tenths of an inch at best. The main change with this forecast package was to adjust daytime highs today just a couple of degrees cooler. Otherwise, cloud cover should begin to scatter out Sunday night with much cooler temperatures.
Highs this afternoon will reach into the lower to middle 60s for portions of the area, with lower to middle 50s for those locations that have maintained snowcover from last week's snowstorm.
Winds will remain up some tonight due to some tighter gradients before the ridge settles into the area. an upper low and associated jet streak will move across the area this afternoon into the early night hours. with drier air at the lower levels and no instability to mention. bringing in cooler and drier air and lowering rain chances. high pressure will develop over the southern MS Valley keeping northwest flow over the state.
Temps north of hwy 90 dropping to and below freezing so patchy frost was added to the wx grids as well.
212 AM CST Sun Jan 3 2021 Dense fog has expanded westward early this morning due to favorable radiation cooling over recent snow covered grounds, and evaporation effects from daytime snow melting yesterday moistening the low levels. If the low clouds linger we could see another round of fog develop again early tonight over southeast Kansas, and try to spread west overnight since low-level airmass would remain virtually unchanged.
/28/ Prior discussion below: Tonight and tomorrow: as an upper closed low finally begins to eject NE across the MS and Ohio River Valleys this evening and into tomorrow, the persistent deck of low stratus over the region will begin to degrade and exit to the east as we get into the evening and overnight hours. The light winds and lack of cloud cover brought forth by the high pressure at the surface will help to increase the radiational cooling affect across most of the region except areas in the Golden Triangle where some low level clouds may still be present. Lows will range from the low to upper 30s.
Mild conditions for January continue, with highs today in the lower and middle 30s, and lows tonight mostly in the 20s. Pattern synopsis and forecast: Continued dry air and upper level ridge will provide quiet weather for northern Michigan through the forecast period. Southwesterly flow on the western periphery of said upper level ridge will continue to provide above normal temperatures for this time of the year. with daytime highs in the mid 30s and lows a good 10-15 degrees above normal, only dropping into the low to upper 20s.
Light winds and weak low-lvl troughing will help keep stratus entrenched across the area through the daytime hours, especially east of I-29.
The main difference will be that a more southerly component to the steering flow will favor the Middle Keys, rather than the Lower Keys. A cold front is still expected to reach the southeastern Gulf on Sunday afternoon and pass the Keys on Sunday evening. As winds initially turn northwest and north late Sunday, the muggy air could interact with the cooler Gulf waters north of the Lower Keys to generate some sea fog. The onset of northerly winds would then push any fog near the Middle/Lower Keys before dissipating or lifting over warmer oceanside waters.
Bands of light rain over the Cumberland Plateau are associated with a midlevel vort max moving around the closed low over the MO bootheel. However some scattered light showers may persist in northern sections into Sunday morning as the surface front moves through and the closed low moves across KY. A surface cold front continues to push off the Cumberland Plateau late this evening with an extensive MVFR deck just behind the front.
1251 AM EST Sun Jan 3 2021 Flight conditions will continue to deteriorate from north to south early this morning as a cold front moves southeast through the area.
233 AM CST Sun Jan 3 2021 Overnight satellite imagery detects a large area of dense fog/freezing fog along the OK/KS border into southwest MO, with patchy valley fog noted across northwest AR. Otherwise, a fast moving but moisture starved upper low will zip across the region today with little impact to the sensible weather. HRRR/forecast soundings suggest additional patchy freezing fog will be possible again tonight.
A passing upper level low will move through Kansas today and bring with it nothing more than a few mid to high level clouds. Highs today should make it into the lower to mid 50s.
Stratus at this time of year often linger longer than models suggest, though, so confidence in the timing of the erosion of the low clouds isn't high.
300 AM EST Sun Jan 3 2021 Low pressure will track northeastward across the eastern Carolinas this morning, then off the middle Atlantic coast today.
952 PM MST Sat Jan 2 2021 The short term period remains dry with slightly warmer than average temperatures for this time of year as high temperatures remain in the middle 40s to lower 50s and lows stay mainly in the 20s.
SPC mesoanalysis has the 700-500mb omega max placed right over the far east-central CWA where column RH is up above 90% in the deformation zone of a broad upper low located in southern Illinois. The highest snow amounts are expected to the east and southeast of Princeton, IL. There is a low chance for patchy freezing drizzle as well but do not see this as a significant threat. Uttech A closed upper level low was located over northwest AR with an associated vort max trailing to the south. The upper level jet has rounded the base of the trough indicating the system will now quickly lift northeast.
HTL and GOV have both seen temps rise from circa 10f to the low/mid 20s as the clouds roll in. Note, this stratus deck is rather low, especially over the higher terrain of the interior. Aforementioned closed southern stream wave is expected to migrate into and through the lower/eastern lakes region later tonight through Sunday, bringing another round of precip through southern Lower Michigan. Model low level RH forecasts/soundings as well as MOS guidance all remain very bullish in saturating the low levels again tonight, suggesting the redevelopment/expansion of stratus and/or fog across the region. And given temps today just getting above freezing.
Temperatures below freezing will result in some freezing fog/slick spots on elevated surfaces.
Later today, an upper disturbance will pass overhead while dragging a weak cold front through the area.
1257 AM EST Sun Jan 3 2021 Low pressure will move up the Ohio Valley and cross the area tonight into Sunday.
153 AM MST Sun Jan 3 2021 The short term period remains dry with slightly warmer than average temperatures for this time of year as high temperatures remain in the middle 40s to lower 50s and lows stay mainly in the 20s.
Southeasterly winds return on Sunday as high pressure works offshore, with light and variable winds returning Sunday night. High pressure works further offshore, turning winds more south and southeasterly into Sunday afternoon. /issued 237 PM CST Sat Jan 2 2021/ SHORT TERM (Tonight through Sunday Night): High pressure remains in control in the short term with pleasant and dry conditions expected. Sunday, southerly winds return as high pressure moves eastward with temperatures warming into the low to mid 70s under mostly sunny skies.
Just east of this area, low clouds and dense fog have kept readings warmer in the teens and 20s.
243 AM CST Sun Jan 3 2021 08Z water vapor showed a couple mid level low pressure systems over the central plains and OH river valley slowly moving east with fast mid level flow moving over the west coast. At the surface, ridging was centered over the Gulf coast and lower MS river valley with general troughing from the southern high plains through the northern plains. Lows tonight are forecast to fall into the lower and middle 20s.
The main part of the forecast will revolve around the trough moving across the center of the CONUS around mid-week.
327 AM EST Sun Jan 3 2021 Synopsis/Discussion/Marine - Light snow leads to localized travel impacts this AM - Patchy drizzle/freezing drizzle at times the next few days - Light snow leads to localized travel impacts this AM At 300 am. The high res models show this area of light snow to spread into the I-94 corridor over the next couple of hours. - Patchy drizzle/freezing drizzle at times the next few days The DGZ remains largely unsaturated through the next couple of days. In addition the low levels remain moist and temperatures will hover around freezing. Already we have seen some freezing drizzle very early this morning.
358 AM EST Sun Jan 3 2021 Weak low pressure will cross the region today and tonight with some light snow, which will briefly mix with a little freezing rain this morning across the western Southern Tier.
Much of this dense fog is in the form of freezing fog as temperatures continue to hover around or below freezing. Freezing fog may cause poor driving visibility and contribute to slick roadways, especially on bridges and overpasses. For tonight, models and forecast soundings depict the return of fog and freezing fog to the region.
329 AM EST Sun Jan 3 2021 Early morning IR and water vapor satellite imagery is showing a band of clouds and moisture stretching from northern Florida to the southwest across the eastern Gulf of Mexico, oriented along and just ahead of the cold front pushing through the area. Between the clouds and moderate northwest winds behind the front, afternoon temperatures will be several degrees cooler today, particularly from around Interstate 4 north.
308 AM EST Sun Jan 3 2021 Light snow will fill in across the area early this morning as forcing increases along and north of track of upper low pressure system now lifting through the Ohio Valley region. Between a slight drift north in best forcing this morning within the 00z and beyond model solutions and mild surface temperatures (34F) through the Lake Erie basin, have realigned the snowfall amounts slightly to focus the heaviest amounts in the I-696 to M-59 corridor region angling southwest over the higher terrain of the Irish hills. Subsidence in the wake of this system will also strengthen the low level temperature inversion and lower its height into tonight.
Snow exits by late morning with highs in the low to mid 30s.
319 AM EST Sun Jan 3 2021 A deep closed low has been spinning across the Ohio valley this morning, providing low clouds and precip to the area. Temperatures will be near freezing for a short time. Considering how light precip has been, and with road temps above freezing, still do not expect much of an impact this morning. With a vertically tilted trough in place, the 500mb low is located over the IN/OH border. Clouds will hang on for most folks across the region today as we stay saturated in the low levels underneath a deep inversion.
Still monitoring the passage of a mainly dry cold front later today. Will maintain current forecast and continue to monitor for any shifts in this cold front's timing. The result will be quite warm temperatures across the CWA today, with most areas expected to get into the 40s and some areas into the low to mid 50s. Breezy winds are possible today, especially later in the afternoon as a cold front approaches the area. High pressure ridge will provide for mainly dry conditions and lessening winds as well.
At the surface, high pressure will slowly nudge east which will allow southerly flow to continue throughout the day. WAA will allow for temps to warm into the low to mid 70s today. However, we will be a few degrees warmer as a result of the southerly flow.
Temperatures are at or near freezing, so this could enhance frost formation on elevated surfaces early this morning. As the high departs to our east tonight, calmer winds in the east should allow for better radiational cooling, with light southerly winds over northeast LA and the ArkLaMiss Delta region keeping temperatures there a few degrees warmer. /NF/ The upper wave moving out of the Rockies this morning will generally dig out a trough over the eastern half of the country, resulting in somewhat northwesterly flow aloft over the region. Any precip is shunted off to the north and east with the waves as high pressure builds into the region.
A quickly approaching trough from the northwest will swing through late tonight and early Monday. Forecast soundings show a rather pronounced inversion with temperatures well above freezing from 2k to 5kft. Given these factors, freezing rain would be the preferred p-type, but some cooling of the inversion also takes place with the frontal circulation which could also favor snow. PoPs are only 20-40 percent, so to keep it simple the forecast simply reads chance of snow, sleet, and freezing rain. Gustier westerly flow will finally kick out any low level moisture behind the front Monday afternoon and temps should rise above freezing with the return of sunshine.
The start of the work week looks pleasant with high pressure building in bringing sunshine and a chance for warm temperatures.
/issued 405 AM CST Sun Jan 3 2021/ A clear sky and light winds overnight have combined to yield very good radiational cooling conditions across the region, with current temperatures down into the lower/mid 30s along and north of I-10. A healthy warm up is forecast, with highs today climbing into the lower/mid 60s amid plenty of sun and low level S/SW flow. A deeper return flow will become established TUE night into WED ahead of another upper trof digging into the Central CONUS, which is forecast to drive another cold front through the area WED night into THU.
/issued 344 AM CST Sun Jan 3 2021/ SHORT TERM (Now through Monday): While high pressure persists at the surface, a weak 500 mb trough will traverse the BRO CWFA from west to east during the period. Despite the passage of the trough, dry weather will prevail for Deep South Texas and the Rio Grande Valley.
405 AM CST Sun Jan 3 2021 A clear sky and light winds overnight have combined to yield very good radiational cooling conditions across the region, with current temperatures down into the lower/mid 30s along and north of I-10. A healthy warm up is forecast, with highs today climbing into the lower/mid 60s amid plenty of sun and low level S/SW flow. A deeper return flow will become established TUE night into WED ahead of another upper trof digging into the Central CONUS, which is forecast to drive another cold front through the area WED night into THU.
Areas of dense freezing fog were occurring over the interior of the forecast area, with only patchy light fog over the far north and near the lake and bay. Expect the low clouds to spread back into much of northern WI tonight. An upper level trough and associated cold front may bring a chance of snow showers to the region Monday afternoon, but the timing, strength and available moisture with this system are in question.
213 AM MST Sun Jan 3 2021 09z surface analysis had trough east of the CWA with lee trough developing from central MT into central WY. Water vapour had ridge pushing from the Rockies into the northern Plains in wake of disturbance sinking into the central/southern Plains. Today/tonight, Pacific northwest upper trough races across the US/Canadian border. Monday, upper ridge builds back into the northern plains ahead of yet another upper trough moving from the west coast into the Rockies.
350 AM MST Sun Jan 3 2021 Another cold front will bring stronger winds through Central and Eastern Montana this afternoon. Although last night started off with boundary layer decoupling, winds started ramping up after midnight to quickly mix out the cooler air. Highs are expected to be in the 40s to lower 50s across the area and with temperatures expecting to be warmer than yesterday, more widespread lower 50s is a possibility and Glasgow Airport could break the previous record high of 50 degrees. A progressive weather pattern is in store beginning with an amplified ridge on Monday with some sun, however, temperatures will not be enhanced by downsloping and will be end up being about 5 to 10 degrees cooler.
Low amplitude "dirty" ridge pattern remains in place across the region, with early morning satellite imagery depicting enhanced cloud cover spreading eastward along the lee of the Sierra.
910 AM EST Sun Jan 3 2021 A mid level low pressure system over the region this morning will move off to the northeast through the day. High pressure will build in tonight and then move off to the east on Monday. A weak cold front will cross the area Monday night followed by another high pressure system. Upper low center near west central Ohio will move northeast, tracking across the northern forecast area for the remainder of this morning. Cannot completely rule out a brief period of freezing drizzle in some locations as temperatures cool ever so slightly later in the night.
/issued 352 AM CST Sun Jan 3 2021/ A small warming trend will be underway today as temperatures rebound into the 50s as high pressure builds in for the first half of the week.
556 AM EST Sun Jan 3 2021 Aviation - Light snow leads to localized travel impacts this AM - Patchy drizzle/freezing drizzle at times the next few days - Light snow leads to localized travel impacts this AM At 300 am. The high res models show this area of light snow to spread into the I-94 corridor over the next couple of hours. - Patchy drizzle/freezing drizzle at times the next few days The DGZ remains largely unsaturated through the next couple of days. In addition the low levels remain moist and temperatures will hover around freezing. Already we have seen some freezing drizzle very early this morning. With temperatures near or below freezing at times. some freezing drizzle could occur. As the southwest flow picks up ahead of an approaching cold front Monday.
352 AM CST Sun Jan 3 2021 A small warming trend will be underway today as temperatures rebound into the 50s as high pressure builds in for the first half of the week.
429 AM EST Sun Jan 3 2021 A cold front will move through the area this morning. High pressure will then prevail through the middle of the week.
Short term hi-res models push the trough through the area by about 9 am and that should take most of the fog risk with it. Regarding the rest of the day, most of the area is starting out 10-12 degrees warmer than yesterday, with several locations near 30 degrees. We will see a few more clouds associated with the upper low and some cold advection, but that will be offset by a westerly flow. In the end, high temperatures today should be similar to yesterday with the cooler temperatures in the east and the warmer temperature in the south.
651 AM EST Sun Jan 3 2021 High pressure will build over the region today and Monday.
For Monday with the westerly winds expecting the highs to climb into the mid 30s or better for all areas as valley warming westerlies continue into the afternoon.
The High Wind Warning in the Cody Foothills continues through noon and that timing seems fine. Highs on Monday will be a few degrees milder as slightly warmer air arrives ahead of the next weather system. The beginning of the period shows the area in a transition with the ridge continuing to move further to the east and a trough moving into WY.
Much of this dense fog is in the form of freezing fog as temperatures continue to hover around or below freezing. Freezing fog may cause poor driving visibility and contribute to slick roadways, especially on bridges and overpasses. For tonight, models and forecast soundings depict the return of fog and freezing fog to the region. As we head into the early week a ridge of high pressure builds over the central CONUS.
Winds will relax and briefly turn west to northwest overnight and north to northeast Monday, as the low proceeds east and weakens across AR/OK and high pressure builds behind it, while the high pressure over LA dips south-southwestward into the Gulf waters. Forecast soundings show rising temperatures along the sfc to 600mb on Monday and will help maintain the warmer conditions across the local area, with highs rising into the upper 60s and low 70s.
SHORT TERM (Now through Monday): While high pressure persists at the surface, a weak 500 mb trough will traverse the BRO CWFA from west to east during the period. Despite the passage of the trough, dry weather will prevail for Deep South Texas and the Rio Grande Valley.
307 AM PST Sun Jan 3 2021 Mostly onshore flow will prevail this week as a series of low pressure systems move inland along the West Coast with precipitation remaining north of the area. There will continue to be periods of high clouds this week, especially with each low pressure system moving inland.
423 AM EST Sun Jan 3 2021 A relatively warm early January morning across much of the Florida Keys with temperatures mainly in the lower to mid 70s. Big Pine Key is the exception (as it often is) with radiational cooling haven taken the temp down to 65 degrees (an impressive 5 degrees cooler than the prevailing dew point).
With sunny skies, we'll continue the warming trend and highs should reach the upper 60s and lower 70s except cooler across the western Hill Country. Overnight, should stay a few degrees warmer than what we're currently seeing thanks to slightly increased dew points. A slight warming in 850 mb temperatures is forecast on Monday and mixing should be sufficient to allow an even warmer day on Monday in many spots with highs in the 70s except upper 60s across our northern tier of counties.
Strong and gusty winds will move over the lower elevations this afternoon, behind an associated cold front.
The result will be quite warm temperatures across the CWA today, with most areas expected to get into the 40s and some areas into the low to mid 50s. Breezy winds are possible today, especially later in the afternoon as a cold front approaches the area. High pressure ridge will provide for mainly dry conditions and lessening winds as well.
Clouds will slowly erode from southwest to northeast this afternoon as an upper level low over the Ohio Valley pulls away. Lows Monday morning will be several degrees cooler as a result of less cloud cover.
Due to the localized nature of the lowest vsbys, wl highlight the impacts in the HWO.
/Issued 308 AM CST Sun Jan 3 2021/ An upper level short wave trough will move northwest to southeast across Kansas today with little fanfare for the Panhandles. A weak cold front will move through the Panhandles Monday morning in association with a short wave trough the moves across the northern Plains. High temperatures on Monday will be about the same as today as the cold air advection is lacking behind this cold front.
308 AM CST Sun Jan 3 2021 An upper level short wave trough will move northwest to southeast across Kansas today with little fanfare for the Panhandles. A weak cold front will move through the Panhandles Monday morning in association with a short wave trough the moves across the northern Plains. High temperatures on Monday will be about the same as today as the cold air advection is lacking behind this cold front.
Satellite and surface observations are continuing to detect freezing fog for parts of far NE OK and NW AR with the bulk of the fog activity outside of the CWA. The latest guidance suggests a brief window for the lower atmosphere to saturate before the system clears the area and brings in drier air behind it. This FG would likely be FZFG as we are expecting freezing temperatures tonight into tomorrow morning. /Issued 233 AM CST Sun Jan 3 2021/ Overnight satellite imagery detects a large area of dense fog/freezing fog along the OK/KS border into southwest MO, with patchy valley fog noted across northwest AR. Otherwise, a fast moving but moisture starved upper low will zip across the region today with little impact to the sensible weather. HRRR/forecast soundings suggest additional patchy freezing fog will be possible again tonight.