Aikyam-Lab/Synoptic-Bench huggingface dataset:
At the surface, a rather weak cold front remains across the peninsula, with abundant cloudiness and a few light showers and/or sprinkles continuing. Some cooler air will filter in the region tonight, so temperatures Wednesday morning will be cooler than they were today, although backing winds just above the surface should lead to continued cloud cover. For Wednesday, a mid/upper-level closed low/trough will move across the southeast with the frontal boundary lingering across the peninsula.
First we'll start with the dying cold front to our north and northwest. Meanwhile, a pre-frontal trough moved through the region overnight and backed our winds to the northwest and north.
Large area of high pressure aloft will be keeping things stable (dry) and warm, much above normal warm tonight and Wednesday. Looks like the strong cold front forecast to barrel through the region by the end of the period is still going to happen.
SUNSHINE AND ABOVE FREEZING TEMPERATURES ARE FOUND AREA WIDE THIS AFTERNOON! The 2nd consecutive day of sun has is taking place, thanks to a large high pressure area, and a rather mild air mass. The ridge of high pressure will remain overhead tonight, and with that, skies should be covered by only high clouds, otherwise, clear, allowing for decent radiational cooling this evening, and by 9 PM, likely fog development.
526 PM CST Tue Jan 12 2021 (This evening through Wednesday) Dry weather will persist across the area through Wednesday, along with warmer temperatures. Some high clouds linger across the area this afternoon, associated with an upper low moving across southern sections. The upper low will move off to the east this evening, with cloud cover decreasing. Southwest winds and warmer temperatures will occur tomorrow, with afternoon highs in the upper 50s and lower 60s.
/NEW/ /Through Wednesday Night/ A robust, yet compact, upper low is making its way across Central and South Texas this evening, but should have little to no impact on the sensible weather locally. A band of forced ascent ahead of the trough is helping develop an area of convective precip over Central Texas that will move east through the night. As the upper low moves into Louisiana early tomorrow morning, drier air aloft will move into the area and allow for mostly sunny skies underneath passing upper clouds.
240 PM PST Tue Jan 12 2021 Dry weather and foggy mornings this week as high pressure prevails.
Skies remain mostly clear with dry conditions through tomorrow as high pressure dominates western Kansas. As for temperatures, lows tonight are anticipated to fall into the low to mid 20s with highs tomorrow reaching well above normal in the low to mid 60s.
458 PM EST Tue Jan 12 2021 High pressure crosses the region tonight through Wednesday.
Expect that fog will expand through the night, and with temperatures falling into the mid and upper 20s, freezing fog is expected. The main change to the grids will be to add a mention of freezing fog. H5 trough has finally moved east of the Appalachians this afternoon and low level moisture is slowly clearing from west to east with some lingering low cloudiness east of I-75 and I-81. Temperatures finally rebounding into the lower to mid 40s at most locations. With temperatures dropping below freezing areas of Freezing fog may form too. High pressure will build over the area tonight and Wednesday. However a another closed off weak upper low over west Texas today will move east across TX and LA tonight and the states just south of TN Wednesday.
Despite the increasing cloud cover, temperatures will still drop off quickly overnight and reach near or below freezing areawide.
As a result temperatures hovered right around freezing for most of the day in that area. With no clouds in site at this hour and none expected for the overnight hours we should see radiational cooling bring temperatures back into the 20s, with some areas in the low 20s by Wednesday morning. This, along with little to no wind, could encourage the development of patchy freezing fog after midnight tonight. We're in store for a slightly warmer day tomorrow as skies stay mostly clear and southerly surface winds prevail.
Some observation sites across the Plateau are showing reduced visibility and expect patchy freezing fog for the Plateau and south through night. Did update the wording from patchy fog to patchy freezing fog since temperatures are below freezing. There could be some radiational cooling and some patchy freezing fog.
May see some sheltered areas drop off pretty quickly into the low 20s, especially over our eastern CWA, however other areas are likely to bottom out in the 25 to 30 degree range thanks to the light winds. If fog becomes more widespread and limiting, then the potential for freezing fog and a few slick spots comes into play for Wednesday morning.
Thereafter, cluster analysis is in very good agreement strong ridging will build into the region trending high temperatures warmer.
Cold front stalling over S FL Peninsula this evening with significant low cloud shield areawide and a few sprinkles continuing in SW FL. High pressure nudging into the region from the Lower MS River Valley filtering cooler conditions for tonight under mostly cloudy skies. At the surface, a rather weak cold front remains across the peninsula, with abundant cloudiness and a few light showers and/or sprinkles continuing. Some cooler air will filter in the region tonight, so temperatures Wednesday morning will be cooler than they were today, although backing winds just above the surface should lead to continued cloud cover. For Wednesday, a mid/upper-level closed low/trough will move across the southeast with the frontal boundary lingering across the peninsula.
442 PM MST Tue Jan 12 2021 Current surface map places weak trof across the central Dakotas, with flat upper level ridge across the Northern Plains. Mild night tonight with low level thermal ridge over the forecast area and cloud cover. Upper level trof crosses the Rockies late Wednesday, with upper low closing off over southern Saskatchewan Wednesday night. Cold front moves into northeast Wyoming/northwest South Dakota late Wednesday afternoon.
741 PM CST Tue Jan 12 2021 Split-flow synoptic pattern continues across the CONUS with a slow-moving, closed low crossing the Lone Star State this evening. With that in mind, the approaching trough will be moisture starved with nil PoPs in the short-term. /issued 311 PM CST Tue Jan 12 2021/ Perfectly clear skies across the Mid-South with light winds and temps in the lower to mid 40s. Clear skies, light winds and some residual surface moisture will lead to some patchy freezing fog later tonight into early Wednesday mainly across NE MS and southeast parts of West TN near the TN River. This could lead to a few slick bridges or overpasses as temps drop into the 20s overnight. The Mid-South will see a warming trend over the next couple of days as a deep trough digs into the western states.
Thick cloud coverage and persistent light northerly flow has maintained much cooler temperatures than expected. High pressure will linger over the area and slowly move east through Wednesday with clear skies and light and variable winds. Temperatures should be about 10 to 15 degrees warmer with highs in the upper 50s to mid 60s.
The southern end of a disturbance will cross northern Utah Wednesday flattening the ridge some.
311 PM CST Tue Jan 12 2021 Perfectly clear skies across the Mid-South with light winds and temps in the lower to mid 40s. Clear skies, light winds and some residual surface moisture will lead to some patchy freezing fog later tonight into early Wednesday mainly across NE MS and southeast parts of West TN near the TN River. This could lead to a few slick bridges or overpasses as temps drop into the 20s overnight. The Mid-South will see a warming trend over the next couple of days as a deep trough digs into the western states.
/issued 311 PM CST Tue Jan 12 2021/ Perfectly clear skies across the Mid-South with light winds and temps in the lower to mid 40s. Clear skies, light winds and some residual surface moisture will lead to some patchy freezing fog later tonight into early Wednesday mainly across NE MS and southeast parts of West TN near the TN River. This could lead to a few slick bridges or overpasses as temps drop into the 20s overnight. The Mid-South will see a warming trend over the next couple of days as a deep trough digs into the western states.
Wednesday looks like a repeat of today in terms of temperature, but perhaps a degree or two warmer, with 925 temps 8-11C advecting into the area. An abrupt end to the warmer weather arrives Wednesday Night as a cold front moves through the area.
Since the low levels are expected to remain dry, not expecting any precipitation from the cloudiness, and cloud cover should keep radiational impacts in check to preclude any significant fog. Canadian high pressure at the surface stretches from South Texas into the Appalachians this afternoon. Aloft clouds are beginning to stream in ahead of an upper low that is moving east across the Big Bend area. Through the rest of the afternoon and tonight cloud cover will move in and thicken as the upper low will move closer. Skies will clear Wednesday morning behind the upper low, and high pressure will become centered in the northern gulf.
Southwest flow coming out of the ridge will bring milder air, without a significant increase in moisture. A weak upper low will move eastward across the Deep South on Wednesday, but its effects should not reach this far north. On Wednesday night, a weak upper trough will ripple through the flow, but should not result in anything more than an increase in high clouds. The warm air advection and fairly dry air will result in ridge/valley temperature differences at night. The last of the low ceilings will break up this afternoon, leaving VFR conditions through the remainder of the period.
442 PM CST Tue Jan 12 2021 Mid-clouds clouds will remain in place through the evening as lift continues ahead of an upper low. Water vapor imagery shows an upper low moving across the Texas. As dry air is pushed in and the upper low moves farther east, the clouds will clear from west to east. At or below freezing temperatures are expected again overnight.
405 PM MST Tue Jan 12 2021 00Z TAF CYCLE Light nw-nly flow aloft through 13/06Z, then nwly flow strengthening over wrn and central NM, as a surface lee trough develops.
502 PM CST Tue Jan 12 2021 Variable high and mid level cloudiness across the region today as GOES water vapor imagery and RAP analysis was showing a weak mid- level trough pushing southeast across MN into WI. Will have to watch for fog development tonight, possibly locally dense, mainly east of the Mississippi River given lighter winds under a weak ridge of high pressure and very moist lower boundary from partial snowmelt today. After some areas of morning fog, may have to contend with some low cloud/stratus mainly east of the Mississippi River in warm air advection ahead of low pressure moving in across the Northern Plains. Typical highs for this date are in the lower/mid 20s.
Southwest flow coming out of the ridge will bring milder air, without a significant increase in moisture. A weak upper low will move eastward across the Deep South on Wednesday, but its effects should not reach this far north. On Wednesday night, a weak upper trough will ripple through the flow, but should not result in anything more than an increase in high clouds. The warm air advection and fairly dry air will result in ridge/valley temperature differences at night.
Satellite and observations are showing mid-level clouds continuing to persist across all aerodromes as high pressure continues to settle over the area. Dry southwesterly flow aloft is then expected behind the passage of this low. Some clearing is expected across the northern ranchlands this evening which will allow for overnight low temperatures to fall into the lower to middle 30s. Farther south, cloud cover will persist a bit longer which will favor lows in the upper 30s across much of the lower RGV to lower 40s near the coast. As skies clear on Wednesday, highs rebounding into the low to mid 60s are expected, followed by efficient radiational cooling overnight.
105 PM PST Tue Jan 12 2021 A Santa Ana weather pattern will maintain fair, dry, and warmer weather across Southern California this week with periods of weak to moderate offshore flow. Building high pressure aloft will amplify the warming for the latter half of the week, when temperatures will be well above average.
313 PM MST Tue Jan 12 2021 Upper ridge over CO tonight and Wed, while short wave trough races eastward from the Pacific NW into the nrn Rockies Wed afternoon.
Wednesday will see south wind in the immediate RRV and Wednesday could end up cooler in the RRV than today and also clouds will increase/thicken up. A cold front will move into central ND in the aftn and move east into MN Wed evening. As it moves east of the RRV Wed evening there is a risk of freezing rain as temperatures drop to around 30/32F.
616 PM CST Tue Jan 12 2021 Primary concern comes at the end of the period as an upper trough moves in from the northern Plains and a cold front works its way across Minnesota. Weak warm advection doesn't look like it will be able to generate much if any precipitation Wednesday into Wednesday night, so most of the area will need to wait until the cold front arrives to see a period of precipitation. Guidance still differs quite a bit on some of the details with this upcoming system, although the cold frontal timing is fairly consistent. This means there could be some window of mixed precipitation (rain or freezing rain depending on near surface temperatures), but that window should be short with things changing over to snow as the entire column cools behind the front.
151 PM PST Tue Jan 12 2021 Low pressure will brush by the region today into Wednesday bringing some periodic light rain to northeast California and far northwest Nevada. High pressure will build late week into the weekend for light winds, weak to moderate inversions, and mild temperatures. Low pressure will move into the Pacific Northwest on Wednesday. Weak warm air advection today and a moisture plume sagging south on Wednesday with the low will bring periods of light rain north of Portola and Gerlach through tomorrow morning, with the best chances late tonight and Wednesday morning. Exposed higher ridges are projected to see wind gusts 50-80 mph.
This will bring an increase in westerly flow aloft & in the low-levels. In addition, some areas in the NE, in Hwy 82 corridor & Golden Triangle, where clouds will be limited, could fall into the low 20s while mid- upper 20s elsewhere. Some patchy fog can't be fully ruled out but not dense enough for more significant dense fog/freezing fog. Some increasing deep layer moisture could bring the potential for non-measurable sprinkles under the closed low. Due to the cold core low aloft swinging through, low-level thermal trough will remain, with only a small increase in warmth in low-levels.
448 PM CST Tue Jan 12 2021 Upper level trough currently spinning across Central Texas will continue moving eastward towards to Toledo Bend Country by 12z Wed and east of the Miss River Valley by 18z Wed or east of our airspace. Despite the increasing cloud cover, temperatures will still drop off quickly overnight and reach near or below freezing areawide.
A warming and drying trend will develop through late week and into the upcoming weekend as high pressure builds over the state. Meanwhile, a persistent mid/upper level ridge building over central and southern California continues to deflect most of the moisture well to our north. The aforementioned ridge out over the Pacific will continue to build inland across the state through late week resulting in a gradual warming trend.
226 PM MST Tue Jan 12 2021 Current surface map places weak trof across the central Dakotas, with flat upper level ridge across the Northern Plains. Mild night tonight with low level thermal ridge over the forecast area and cloud cover. Upper level trof crosses the Rockies late Wednesday, with upper low closing off over southern Saskatchewan Wednesday night. Cold front moves into northeast Wyoming/northwest South Dakota late Wednesday afternoon.
As a matter of fact, we've only risen a degree or two since this morning with current temperatures in the lower 70s.
Morning temperatures should be a few degrees warmer than those seen this morning in most spots.
1023 PM MST Tue Jan 12 2021 Current surface map places weak trof across the central Dakotas, with flat upper level ridge across the Northern Plains. Mild night tonight with low level thermal ridge over the forecast area and cloud cover. Upper level trof crosses the Rockies late Wednesday, with upper low closing off over southern Saskatchewan Wednesday night. Cold front moves into northeast Wyoming/northwest South Dakota late Wednesday afternoon.
1053 PM CST Tue Jan 12 2021 (This evening through Wednesday) Dry weather will persist across the area through Wednesday, along with warmer temperatures. Some high clouds linger across the area this afternoon, associated with an upper low moving across southern sections. The upper low will move off to the east this evening, with cloud cover decreasing. Southwest winds and warmer temperatures will occur tomorrow, with afternoon highs in the upper 50s and lower 60s.
Lows on track tonight in the low 20s or upper teens. Wednesday will see south wind in the immediate RRV and Wednesday could end up cooler in the RRV than today and also clouds will increase/thicken up. A cold front will move into central ND in the aftn and move east into MN Wed evening. As it moves east of the RRV Wed evening there is a risk of freezing rain as temperatures drop to around 30/32F.
310 AM EST Wed Jan 13 2021 Primary concern is the coverage of freezing fog this morning. Temps in line with forecast and already well below freezing. Areas near lakes and ponds will be most prone to freezing fog, but can't rule out valleys and other areas prone to dense fog. Fog and freezing temps will improve quickly after 9 AM. Another chance for patchy light freezing fog tonight but likely less confidence and coverage than this morning.
1005 PM MST Tue Jan 12 2021 06Z TAF CYCLE Strengthening nwly flow aloft over wrn and central NM as a surface lee trough develops.
216 AM CST Wed Jan 13 2021 A frigid overnight has commenced with many in the low to mid 20s and even a few in the teens. More widespread freezing fog appears to have stayed to our south and east so far this morning. Could see a few places on the Plateau get some freezing fog before sunrise, but not expecting this to be widespread. Today should be much warmer than yesterday with highs closing in on 50. Even warmer temps are expected tomorrow with many reaching the low to mid 50s.
300 AM EST Wed Jan 13 2021 A ridge of high pressure will be the dominant weather feature in the short term for eastern Kentucky. A few locations in the Cumberland Valley may see some freezing fog this morning, but that should dissipate rather quickly once the sun has been up for a bit. Todays highs will top out in the upper 40s, with most locations reaching the lower 50s on Wednesday. Conditions should favor another ridge valley temperature split late tonight, so that was reflected in the grids once again. Lows on Wednesday are expected to fall into the lower 20s in the valleys, but only to around 30 on the surrounding ridges. Winds will be generally out of the south or southwest the next couple of days, which will be what leads to our warmer temperatures.
1050 PM EST Tue Jan 12 2021 A cold front passed south across the keys earlier this evening.
The primary 500 mb trough will remain off the north over Ontario where the greater forcing and greater chance for any precipitation will reside. The higher coverage of clouds Wednesday night will help hold overnight temperatures to around 30 degrees.
1102 PM MST Tue Jan 12 2021 Upper ridge over CO tonight and Wed, while short wave trough races eastward from the Pacific NW into the nrn Rockies Wed afternoon.
VFR conditions will continue to prevail through the TAF period with high pressure overhead. Satellite and observations are showing mid-level clouds continuing to persist across all aerodromes as high pressure continues to settle over the area. Dry southwesterly flow aloft is then expected behind the passage of this low. Some clearing is expected across the northern ranchlands this evening which will allow for overnight low temperatures to fall into the lower to middle 30s. Farther south, cloud cover will persist a bit longer which will favor lows in the upper 30s across much of the lower RGV to lower 40s near the coast. As skies clear on Wednesday, highs rebounding into the low to mid 60s are expected, followed by efficient radiational cooling overnight.
Temperatures tonight are not as cold as recent nights, as the lower troposphere continues to warm, and scattered cirrus arrive north of the ridge axis, interfering with radiational cooling. The anticipated cold front is expected to enter NW Kansas around midnight tonight, and then roar through the SE zones/south central Kansas by 6 am.
Expect that fog will expand through the night, and with temperatures falling into the mid and upper 20s, freezing fog is expected. The main change to the grids will be to add a mention of freezing fog. CDG Chattanooga Airport, TN 27 51 29 54 37 / 0 0 0 0 20 Knoxville McGhee Tyson Airport, TN 26 49 28 53 35 / 0 0 0 0 20 Oak Ridge, TN 24 50 27 51 35 / 0 0 0 0 20 Tri Cities Airport, TN 25 47 25 52 30 / 0 0 0 0 10.
/NEW/ /through Wednesday night/ We will continue to see some light radar returns across the southeast zones into the overnight hours as a compact upper low rotates towards East Texas. The upper low and associated clouds/ precipitation will exit the region before sunrise Wednesday. The cloud cover associated with the upper low will keep temperatures up a bit overnight, especially across the southeast zones. Lows will range form the upper 20s in the west to the lower 30s across the southeast and the urban heat island of the Metroplex. Temperatures will warm into the the mid 50s to lower 60s and lows Wednesday night will be above freezing, ranging from the mid 30s to the lower 40s.
Therefore, no adjustments were made to increase PoP values, however, minor temperature adjustments were made to account for increasing cloud cover maintaining slightly warmer conditions in our western and southwestern zones. /issued 448 PM CST Tue Jan 12 2021/ Upper level trough currently spinning across Central Texas will continue moving eastward towards to Toledo Bend Country by 12z Wed and east of the Miss River Valley by 18z Wed or east of our airspace.
Some observation sites across the Plateau are showing reduced visibility and expect patchy freezing fog for the Plateau and south through night. Did update the wording from patchy fog to patchy freezing fog since temperatures are below freezing. This will allow for light freezing fog to develop.
This will cause a cold front to surge southward across Kansas late tonight. RAP model shows deeper low-level mixing just behind surface cold front which could create a brief spike of stronger northwest winds during the overnight hours.
There is also a slight chance of freezing rain in the northern wind-sheltered valleys, including Baker County and Upper Weiser Basin. Snow levels will start to lower with the arrival of a cold front Wednesday afternoon.
Updated for near-term trends and 06Z Aviation Area Forecast Updated forecast to indicate areas of freezing fog this morning thru 9 AM. Coverage will not be widespread but already have reports of dense fog with temps of 25-30F which is sufficient for freezing fog advisory.
Breaks in the high cloud cover will help the fog develop as well. At this point, not expected widespread or dense fog due to the low level mixing.
That cloud coverage exits the airspace with the upper level trough as it continues eastward, clearing KMLU by 13/18Z. Therefore, no adjustments were made to increase PoP values, however, minor temperature adjustments were made to account for increasing cloud cover maintaining slightly warmer conditions in our western and southwestern zones.