Aikyam-Lab/Synoptic-Bench huggingface dataset:
A rare, December dense fog event continues for most of the Lower and Middle Keys as well as the adjacent nearshore coastal waters and the southeastern Gulf of Mexico. Temperatures range vastly among island communities, generally 70 to 75 in the Lower and Middle Keys, to the upper 70s across the fog-free Upper Keys. We did elect to nudge maximum temperatures downwards owed to the low stratus and fog for the Lower and Middle Keys. A Dense Fog Advisory remains in effect for the coastal waters adjacent to the Lower and Middle Keys, including the Bayside and Gulfside marine zones and western Hawk Channel, as well as the southeastern Gulf of Mexico, including the Dry Tortugas. In the wake of the front, strong high pressure builds across the eastern United States resulting in a strengthening pressure gradient.
1202 PM CST Thu Dec 19 2024 (Today through Friday) First cold front is through with cooler drier air in tow. This front will bring another even colder blast with it to bring our lows into freezing again. We will diddo the highs today and Fri.
Highs today will remain above average, but coastal areas will be a few degrees cooler than yesterday. Cooler conditions will spread further inland Friday through the weekend.
Although diurnal curves were slowed due to the earlier clouds, we should be able to warm close to our previously forecast highs this afternoon, ranging from the lower 50s in the north to near 60 across the far southeast. Another cold front will also quickly move southward with another push of colder and drier air behind it. Other than a few clouds, that's all that we expect to see from the cold front with no moisture to speak of. As the colder air moves southward, highs should be slightly lower Friday, ranging from the low to mid 40s in Marion County to the middle and upper 50s in Barbour County before the front moves through.
255 PM EST Thu Dec 19 2024 An Arctic cold front and strong upper level disturbance will approach from the west late tonight and cross the area Friday through early Friday night.
The upper level ridge will continue to build over the region today, bringing dense fog and low stratus clouds to the Lower Treasure and Long Valleys.
1141 AM CST Thu Dec 19 2024 Colder weather is on tap for the Mid-South going into this weekend as high pressure builds in.
Upper level ridging nudges eastward into the region for the weekend, followed by a more zonal/split flow moving into Christmas week. Additional snowfall amounts will range from a trace to 2 inches, with the higher amounts through southwest MN.
Meanwhile, low clouds and patchy fog and freezing fog are ongoing in the interior westside valleys and freezing fog in and around Klamath Falls. The low clouds and fog should burn off in these areas close to noon.
(Today and tonight) A cold morning across the area with temperatures at or below freezing across much of the area, the coldest being Sterling City at 25. However, expect warmer temperatures today with highs in the mid 60s to lower 70s. Another chilly night with lows in the 30s, with low lying areas and river valleys in the lower 30s. (Friday night through next Thursday) A ridge across the southwestern U.
- After lake effect snow Friday night, gradually trending warmer with periods of rain. Michiana will be the pivot point for this low which indicates snow will be most persistent/prolonged tonight through Friday morning there. Elsewhere snow develops along the surface cold front, bringing snow to an area from US 30 south through US 24. Instead, snow will be most persistent across Michiana along the northern edge of the low. After daybreak Friday, light snow persists across the forecast area as the low continues to drop south. High pressure centered over northern Minnesota and our departing low over the central Appalachians favor a lake effect snow band impacting the southwest shore of Lake Michigan.
938 AM CST Thu Dec 19 2024 Updated at 935 AM CST Thu Dec 19 2024 - Strong cold front late week will bring below normal temps for Friday into the weekend with dry weather persisting. Patchy low clouds and fog continues this morning in the lower Arkansas River Valley and the valleys of northwest Arkansas.
Updated at 215 PM CST Thu Dec 19 2024 - Strong cold front moving through will result in a chilly Friday.
1041 AM MST Thu Dec 19 2024 - Unseasonably warm and dry conditions continue into the weekend with high pressure overhead.
127 PM MST Thu Dec 19 2024 - DRY WEATHER AND WARMER TEMPERATURES CONTINUE TODAY AND FRIDAY.
139 PM MST Thu Dec 19 2024 High pressure over the region will keep things quiet through the day Friday. This COULD be a bit more widespread than it was this morning so have patchy freezing fog in the forecast for a good portion of the Snake Plain, Magic Valley, Arco Desert and up towards the Island Park region. Another Freezing Fog may be needed depending on how this transpires but confidence is too low for any issuance at the moment. Otherwise, things will remain quiet with temperatures on the warmer side of normal. Any prolonged fog/stratus could cause slightly cooler daytime high temps however for Friday, much like today with KIDA still at 24 compared to KPIH and KBYI at 37 and 40, respectively.
18z surface map showed 1012 mb Alberta clipper low pressure along the IA/MN border. South winds ahead of the low were gusting up to 30 mph west of the IL River, bringing in seasonably mild mid/upper 30s 1 pm temperatures. Winds to veer northwest behind the cold frontal passage overnight, and tightening pressure gradient in cold advection supports 25-35 mph wind gusts in a 3 am to 3 pm window, as advertised by 12z HREF.
935 AM PST Thu Dec 19 2024 A ridge of high pressure will result in a drying trend and calmer winds through Friday. A ridge will bring dry, warm conditions to most locations. Ensembles continue to push moisture up the western flank of the ridge along the Cascades with a 30 percent probability of occurring.
Upper level ridging nudges eastward into the region for the weekend, followed by a more zonal/split flow moving into Christmas week.
Fair weather continues thru Friday night under the influence of an upper ridge.
Have dropped lows a few degrees in many areas, especially across the low lying areas that where cold air drainage is most pronounced. Otherwise, another weak cold front moves across the area late tonight and into the day on Friday. Highs on Friday likely to be a few degrees cooler than they are today, with highs mainly in the upper 50s to low/mid 60s across the area. (Friday night through next Thursday) A ridge across the southwestern U.
Maximum temperatures today will be cooler than yesterday for most locations east of I-25 as a cold front moves across the area.
As of a 1 PM surface analysis, the center of that aforementioned system is located in far north-central Iowa, dragging a cold front that bows down into central Nebraska and then up towards Montana. Ahead of the cold front a downslope-warmed temperature (which tied a record today in Lincoln) and extremely strong wind gusts along and behind the front. Tonight temperatures are expected to tank very quickly behind the passing cold front, with lows expected to bottom out as low as 7 degrees in Cedar and Wayne Counties and in the lower teens farther south. For the rest of Friday, quieter winds will be fully settled in and highs will only reach the lower 20s to around 30 degrees with dry weather set to continue this weekend through much of the upcoming week.
815 PM EST Thu Dec 19 2024 An Arctic cold front and strong upper level disturbance will approach from the west late tonight and cross the area Friday through early Friday night. Weak southerly overrunning and isentropic lift atop a wedge of cool high pressure extending south down the Atlantic Seaboard is supporting widespread stratus with cloud bases running between 2- 5kft across the area.
440 PM MST Thu Dec 19 2024 - Unseasonably warm and dry conditions continue into the weekend with high pressure overhead.
618 PM CST Thu Dec 19 2024 This Afternoon Through Tomorrow: As low-level moisture continues to slowly erode in the wake of our last system, a low pressure system brewing in the Upper Midwest is set to bring us our next cold front.
522 PM CST Thu Dec 19 2024 (This evening through Friday Night) Northwesterly flow remains in place today as a mid/upper trough digs through the Northern Plains/Great Lakes. The aforementioned mid/upper level trough will dig through the Ohio Valley on Friday. Low level ridging building over Western Texas with the aforementioned disturbance to the northeast will tighten the pressure gradient, invigorating CAA.
655 PM EST Thu Dec 19 2024 An Arctic cold front and strong upper level disturbance will approach from the west late tonight and cross the area Friday through early Friday night.
High pressure will remain across the region through the first part of the weekend.
(This evening through Friday Night) Northwesterly flow remains in place today as a mid/upper trough digs through the Northern Plains/Great Lakes. The aforementioned mid/upper level trough will dig through the Ohio Valley on Friday. Low level ridging building over Western Texas with the aforementioned disturbance to the northeast will tighten the pressure gradient, invigorating CAA.
501 PM CST Thu Dec 19 2024 Updated at 215 PM CST Thu Dec 19 2024 - Strong cold front moving through will result in a chilly Friday.
Clearing skies and calming winds tonight in addition to temperatures starting out cooler than forecast will likely allow radiational cooling to take low temperatures below NBM guidance, closer to low 40s to upper 30s. As we move into Friday, temperatures should be largely diurnally driven with a quick warm up into the 60s ahead of the next, much stronger cold front that arrives late in the day.
As the cold front slides south, a plume of moisture in close proximity to the boundary is combining with a light wind, cool SSTs, and a mild evening to create a thick, patch that continues to advect south with the boundary. This should be the last night for awhile as cooler and drier air filters in behind the cold front.
- Cold on Friday, but trending warmer through the weekend. Strong northwest winds continue behind the cold front this afternoon. The High Wind Warning has been expanded southward to include all counties along/north of Highway 92. Winds go light/variable late tonight into Friday morning as high pressure pushes in from the north. This, along with the colder, post- frontal airmass, should allow at least northern parts of the area to dip into the low teens or single digits. Increasing ridging over the western CONUS will allow for a dry and warming trend through the weekend.
539 PM CST Thu Dec 19 2024 (Tonight) An upper level trough axis across the upper Midwest dips south and east towards the local forecast area tonight. This will push a dry cold front through this evening bringing a reinforcement of cold air into the Tennessee Valley. Otherwise, mostly clear skies and light winds tonight make for ideal radiational cooling, dropping overnight lows into the low to mid 30s.
- Cold on Friday, but trending warmer through the weekend. Strong winds behind this afternoons cold front have significantly subsided, and wind gusts in excess of 58 mph are no longer anticipated. For this reason, the High Wind Warning has been allowed to expire. Strong northwest winds continue behind the cold front this afternoon. The High Wind Warning has been expanded southward to include all counties along/north of Highway 92. Winds go light/variable late tonight into Friday morning as high pressure pushes in from the north. This, along with the colder, post- frontal airmass, should allow at least northern parts of the area to dip into the low teens or single digits. Increasing ridging over the western CONUS will allow for a dry and warming trend through the weekend.
Evening radar shows scattered showers just ahead of a cold front approaching the Illinois River at this time. Warm advection behind a warm front that lifted through the area this evening has brought temperatures into the mid and upper 30s with dewpoints into the lower 30s, which is just warm enough to keep most of this precipitation as rain. 18z surface map showed 1012 mb Alberta clipper low pressure along the IA/MN border. South winds ahead of the low were gusting up to 30 mph west of the IL River, bringing in seasonably mild mid/upper 30s 1 pm temperatures. Winds to veer northwest behind the cold frontal passage overnight, and tightening pressure gradient in cold advection supports 25-35 mph wind gusts in a 3 am to 3 pm window, as advertised by 12z HREF.
241 PM MST Thu Dec 19 2024 - Unseasonably warm and dry conditions continue into the weekend with high pressure overhead.
We should also see the lower cloud cover push off to the east during the overnight hours.
Temperatures are cooling as expected, with locally gusty winds developing southwest of the higher terrain.
Unseasonably warm temperatures will continue through this weekend as high pressure continues to dominate the western United States. High pressure continues to encompass much of the western CONUS, promoting anomalously warm temperatures for this time of year with some areas reaching, and even exceeding, record highs. The high yesterday at Phoenix Sky Harbor was 83 degrees, which is 18 degrees above normal for this time of year and also broke the previous daily record of 79 degrees set back in 1950.
458 PM CST Thu Dec 19 2024 (Tonight through Friday night) Key Message: - A dry "backdoor" cold front arrives Friday night. Elsewhere, temperatures will settle into the low- to-mid 50s. However, a reinforcing push of drier air will arrive Friday night as a dry "backdoor" cold front moves into the region. In the wake of this front, overnight lows will become notably cooler.
- Dry weather and warmer temperatures continue today and Friday.
527 PM CST Thu Dec 19 2024 (This evening through Friday Night) High pressure will settle across the region this afternoon into the evening and overnight period. Overnight lows will generally range from the mid 30s to right around 40 degrees, with a few isolated readings in the lower 30s. On Friday, a cold front will rapidly sweep through the region, with some models having the boundary completely through around lunch time. Behind the front, northerly winds will bring in a reinforcing shot of a cooler and drier airmass.
814 PM MST Thu Dec 19 2024 - Dry weather and warmer temperatures continue today and Friday.
Large ridge remains anchored across the Western US with the storm track deflected well to the north into Washington State and British Columbia. This ridge will crawl eastward through the weekend but remain the dominant feature for the area, ensuring a continuation of above normal temperatures and light winds.
Have dropped lows a few degrees in many areas, especially across the low lying areas that where cold air drainage is most pronounced. Otherwise, another weak cold front moves across the area late tonight and into the day on Friday. Highs on Friday likely to be a few degrees cooler than they are today, with highs mainly in the upper 50s to low/mid 60s across the area.
(Today through Saturday) Key Messages - A weak cold front will reinforce cool and dry air today - A light freeze forecast Saturday morning across the Hill Country Cool air and slightly decoupled winds will allow for a few cold pockets in the mid 30s this morning. A moderate reinforcing cold front is slipping into our northern counties and will promote breezy conditions and additional cold air advection to trend our temperatures down slightly over the next 24-36 hours. Mostly clear skies and the low dew points through the short term will help with daytime warming, and near normal high temperatures are still forecast for both today and Saturday.
- Much cooler temperatures remain on the horizon by the weekend. A weak cold front continues to push through the local area today, leading to light northerly winds. Winds will increase out of the west on Friday, as east central Florida becomes sandwiched between the previous weak front and a stronger cold front pushing into the Southeast. The next cold front looks to pass through the local area Saturday, though no precipitation is forecast along it. A more noticeable change will occur on Saturday, as highs only reach the lower to mid-60s, with upper 50s along and north of I-4. Northerly winds 10-15mph will usher in drier air, allowing for overnight lows in the lower to mid-40s over the interior.
Still, we will need to monitor how widespread this fog gets and whether temperatures can slip below the freezing mark for an hour or two just before sunrise. Should this occur an SPS or freezing fog advisory (if fog becomes more widespread) may be needed.
This Afternoon Through Tomorrow: As low-level moisture continues to slowly erode in the wake of our last system, a low pressure system brewing in the Upper Midwest is set to bring us our next cold front.
Near calm and cooler conditions ongoing with a few areas of fog. The mid to upper level pattern will be dominated by a longwave trough over the Eastern U. with a weakening ridge over the Western U. Highs in the lower to mid 60s.
244 AM CST Fri Dec 20 2024 - Much cooler today with rising temperatures through the weekend.
933 PM MST Thu Dec 19 2024 - Brief cool down Friday and Saturday east of Highway 25 with a cold front, but still only slightly below normal. Cold front located in central Nebraska this afternoon will slide south and southeast across the forecast area tonight. Low temperatures will range from the mid teens in eastern areas to the lower 20s in Colorado. An upper ridge over the western CONUS will prevail Friday and Saturday with continued dry conditions.
(Today through Saturday) Currently between two cold fronts, with generally clear skies and cooler temperatures. Cloud cover in the north could result in temperatures a few degrees warmer in the northeast, but will hang with the consensus on the temperatures right now.
We aren't seeing much in the way or widespread low clouds or freezing fog, but there is still some potential. We did include patchy freezing fog for the Snake Plain as well along the Montana Divide. Some of the higher resolution models and to some extent the NAM have more widespread precipitation across and south of the Snake Plain and Magic Valley. We do expect where inversions hold a bit longer today for temperatures to hold closer to the low/mid 30s in the afternoon, and similar Saturday.
Infrared satellite imagery at 08Z Friday morning reveals nearly cloudless skies across the entirety of the central and southern plains ahead of a building upper level ridge west of the Rockies as per latest water vapor satellite and RAP upper air analysis. No noteworthy change is anticipated to this synoptic pattern daytime Friday other than a small vorticity max diving southeast out of southwest Canada on the eastern periphery of the ridge.
Another trough is evident approaching the northern Rockies/Plains, with a corridor of enhanced deep moisture ahead of the trough extending from the east Pacific through southern AB. Latest surface analysis shows high pressure centered over ND, with ridging extending southward through the central Plains, with weak troughing from western AB southward through north central WY. As such, main sensible weather impact with the passage of the trough for us will likely be increasing south/southeasterly winds owing to a tightening pressure gradient and accompanying 2-4 mb/3 hr pressure falls. The trough passage will do little to stymie the expansion of low-level thermal ridging into the area, with 850 mb temperatures probably to likely (60-90% chances) exceeding 10C by Saturday evening across much of the area based on latest LREF probabilities.
However, towards midnight the pre-frontal trough axis that currently extends from eastern Missouri into eastern Arkansas will move east and approach the area. Otherwise, temperatures will likely fall a bit more into the lower to 30s in a few locations east of the I-65 corridor. The upper trough axis remains entrenched across the Southeast resulting in northwesterly flow. While winds will be less, temperatures will struggle to climb above the low to mid 40s with overnight lows plunging into the lower 20s.
We should also see the lower cloud cover push off to the east during the overnight hours. The upper-levels have northwest flow over SD Saturday morning that becomes more zonal through the day as an upper-level ridge moves over the state.
Strong radiational cooling has allowed temperatures to drop into the low 30s to low 40s. A Special Weather Statement was issued for NW GA for potential freezing fog development -- with temperatures at or just above freezing and fog developing along local water bodies -- freezing fog will certainly pose a risk this morning. The main story for the short term will be the passage of a midlevel trough and 'dry' cold front. Drier and cooler conditions prevail as we head into the weekend.
932 PM MST Thu Dec 19 2024 - Winds diminish today, with quiet weather and unseasonably warm temperatures through Saturday under building high pressure. Ridging builds today and winds will thus remain light through Saturday. With building high pressure, while winds are on the decrease, temperatures will be on the rise. What exactly is normal? "Normal" highs for mid- December are generally in the low to mid 30s for most points east of the Divide, and upper 20s west of the Divide.
The mid-level trough over the Eastern Seaboard will begin to advect offshore, although it will amplify as it moves offshore due to a jet streak upstream from the trough that is connected to a building ridge in the central CONUS. Overall, the trough axis will not extend past the northern Florida Peninsula, and thus the only effect from it will be an increase in winds out of the north/northwest. High temperatures for today range from the upper 70s near the lake to the low 80s along the east coast. After today, the continuous dry and cold air advection through Saturday will lead to cooler high temperatures on Saturday in the upper 60s to low 70s.
Also occuring early this morning is an upper level trough passing through the Mississippi River Valley and towards the Mid-Atlantic coast. As it continues on its eastward trek, it'll help push through a reinforcing cold front later today leaving even cooler and drier air in its wake. With clear skies, light wind, and plentiful dry air prevailing, we'll have sufficient conditions for maximum radiational cooling allowing for Friday night's temperatures to drop into the low 30s to low 40s. The main impact that this will have in the short term period is 3-5Â°F warmer overnight temperatures on Saturday night compared to Friday night with low temperatures mainly in the upper 30s to low 40s.
A few locations have already dropped below freezing, which is quicker than previously forecast, so have adjusted overnight lows down by a few degrees across the Panhandles. As high pressure builds in, the wind flow will return from the southwest tomorrow afternoon.
Much cooler drier air will advect over the forecast area today on gusty northwest winds under mostly clear skies. A secondary cold front will push down the peninsula tonight and Saturday with a reinforcing surge of colder drier air.
- Cooler today with highs in the 50s. (Today and tonight) A cold front has now completely moved through the area and light northeasterly winds in its wake will continue through the overnight hours. Winds will switch back to south- southeasterly by this afternoon and an upper ridge will start working its way in. If the winds switch sooner, it may be slightly warmer.
323 AM EST Fri Dec 20 2024 A developing low-pressure center off of Cape Hatteras will move to the northeast away from the region today.