Aikyam-Lab/Synoptic-Bench huggingface dataset:
No Dense or Freezing Fog Advisories at this time, but one may be issued overnight based on observations and webcams. This includes the Lower Columbia Basin and surrounding valleys. Temperatures in the Blues are in the mid to upper 30s while the Basin is in the lower to mid 30s--and indicator that the inversion is becoming stronger with a more likelihood of fog development tonight. The high pressure ridge will be centered over WA/OR/CA tomorrow for dry and stable conditions. Any fog or freezing fog in the lower elevations will gradually decrease during the day--or not at all. The low level inversion will be strong; the top of the inversion will be as high as 8000 feet. However, forecast soundings indicate a rather moist profile in the lower levels, and MET guidance shows BR for many TAF sites.
BT Tonight, an upper ridge will move eastward away from the Northern Rockies and a few weak disturbances will move southeastward over the region. Any snow amounts over the lower elevations should be a half inch or less, and in the mountains amounts could approach a few inches. An upper ridge will move over the region Saturday night and bring weak subsidence and dry conditions.
By Saturday evening and into the overnight hours, winds become light and variable as high pressure slides into close proximity. Therefore, overnight lows in the low to mid 30s look good and no changes needed. /issued 353 PM CST Fri Jan 15 2021/ An impressive mid latitude cyclone responsible for yesterday's frontal passage and today's gusty winds continues to spin across the central U. With this high centered nearly overhead, the weekend is shaping up to be cold, but generally tranquil.
Some scattered light snow showers or flurries remain possible this evening into tonight on the back edge of the departing upper low as a weak deformation axis/stretched vorticity lobe pivots back across MI. While highs Sunday push into the mid 30s, the column aloft will remain below freezing with 850mb temps around -8C leading to a nearly all snow (some melting snow/mix is possible with any early onset precip that falls Sunday afternoon when boundary layer temps will be at their warmest).
Trends in observations and short-term model guidance suggest this will continue through the early morning hours along the edge of the low stratus. Observations and short-term guidance suggest a few areas of patchy fog will develop tonight along the leading edge of the lower stratus. Lingering effects from the recent cold front are starting to dwindle this afternoon. As long as these low clouds linger there could be a few flurries or very isolated freezing drizzle. The air behind it is slightly warmer than our current airmass so expect temps to warm to slightly above normal for Saturday. During the day Sunday looks to be one of the mild days with weak ridging overhead and slightly above normal temperatures.
(Today and tonight) Early this morning, water vapor satellite imagery shows a large upper level low moving east over the Ohio Valley while northwest flow aloft continues over West Central Texas. This, in addition to sunny skies and strengthening of the 850 mb thermal ridge, will lead to warming today, with highs in the low to mid 60s. Expect lows in the low 30s.
A cold front continues to press southeast through the Southeastern Gulf of Mexico. Northwest winds average 20 to 25 knots behind the front, accentuated by Buoy 42003 which gusted in the low 30s for several hours. Prefrontal convection continues to struggle to the west and southwest of the Lower Keys, with tops limited to around 20 kft. Temperatures are in the lower 70s and dewpoints are in the upper 60s. From synopsis, a cold front will push through the coastal waters of the Florida Keys tonight.
As this trough shifts east, expect a gradual increase in snow showers reaching the ground in middle TN, including our southern TN/northeast AL Plateau areas. This drier air will limit ice introduction into the lower clouds this morning, so expecting only scattered flurries for most areas of north AL. High temperatures will be held in the lower 40s in valleys, with middle to upper 30s atop the higher elevations. Weak ridging will shift east tonight, allowing west-southwest flow and warm air advection to increase in advance of the next trough digging through the lower MO valley.
1039 PM CST Fri Jan 15 2021 The stacked low pressure system over the Mid Mississippi Valley will pull away slowly to the east tonight. The eastern edge of the dry slot will move through the remainder of Missouri into Illinois tonight as the low drifts eastward. Split flow across the CONUS with a cut off upper level low over the southwest coast, and fast- moving quasi-zonal flow stretching from the Pacific Northwest across the Plains and the Central US.
921 PM CST Fri Jan 15 2021 (Issued 921 PM CST Fri Jan 15 2021) Low pressure will remain over central Lake MI tonight as the upper low over IL and IN moves east with its axis pivoting north. Low to mid level frontogenesis and warm advection is associated with this trough axis and responsible for the ongoing light snow. Sfc temps have remained at or slightly above freezing with wet snow and light snow accums. This is due to the low pressure system that has been spitting out rain and snow over us since yesterday. The stacked low over western IL will develop another area of low pressure over Lake Michigan this evening before shifting east. Snow ratios should be around 10 to 1 with temperatures around freezing.
Scattered snow showers will develop in Ohio this morning and then expand northeast during the afternoon as another upper low moves overhead. Most locations will see less than an inch in accumulation, with the ridges being the focal point for higher amounts. Expected snow accumulation in the ridges will require a winter weather advisory. Ridging aloft on Sunday will keep most of the day dry. In the wake of the exiting upper low, heights will briefly rise and most of the snow shower activity would be confined to the I-80 corridor and ridges with the minor cold advection and westerly winds.
Therefore, overnight lows in the low to mid 30s look good and no changes needed. Deep low pressure over the Midwest has resulted in a tight pressure gradient over the region, and thus gusty WNW winds throughout the day today. /issued 353 PM CST Fri Jan 15 2021/ An impressive mid latitude cyclone responsible for yesterday's frontal passage and today's gusty winds continues to spin across the central U. With this high centered nearly overhead, the weekend is shaping up to be cold, but generally tranquil.
959 PM CST Fri Jan 15 2021 Had been holding on to Winter Weather Advisory for freezing drizzle potential as KFSD radar was showing some blossoming of drizzly-looking echoes around the radar over the past couple of hours, after the snow moved out of the area. Will still monitor for threat of light freezing drizzle over the next few hours, though no strong indications of development seen just yet. The vertically stacked low pressure center continues migrating southeastward this evening, causing a relaxation in the pressure gradient and therefore decreasing winds. One additional issue that may be introduced this evening through midnight is freezing drizzle. Continued modest lift in the lowest saturated levels may cause liquid drizzle to fall while surface temperatures remain below freezing.
The broad upper low over the region early this morning will slowly spin eastward only to get replaced by another moving into the Midwest early Sunday.
113 AM EST Sat Jan 16 2021 Following the passage of a cold front, dry and cool conditions will overspread the area into the weekend, with breezy conditions during the day Saturday.
1014 PM MST Fri Jan 15 2021 Winds easing this afternoon with gusts below warning levels across the area we had outlined in the High Wind Warnings. Allowed the High Wind Warnings to expire on time at 5 PM this afternoon. Transitory short wave ridge will maintain dry conditions Sunday. Fast on its heels is another Pacific trough.
1041 PM MST Fri Jan 15 2021 A few high clouds are moving into northern portions of the CWA this afternoon as a weak transitory ridge moves through. maybe a wee bit more for the highest elevations. A positively tilted trough axis will dig south along the West Coast.
The low dewpoints will lead to afternoon humidity values in the 15 percent range which will lead to elevated fire weather conditions in the west where wind speeds will be in that 10- 15 mph range. Dry weather will continue through the short-term with only some passing mid-high clouds passing through the area tonight as a trough moves through the state.
Upper level troughing will transition to zonal flow as the upper low over the Ohio Valley this morning lifts northeastward into New England tonight. Highs today will range from the lower 50s north to the upper 50s to around 60 south.
510 AM CST Sat Jan 16 2021 For the 16/12Z TAF update, NW flow continues around the upper low well to our east. Expect VFR conditions through the period as mid to high cloud cover begins to arrive from the north with a weak cold front in our airspace by 17/00Z. /Today through Sunday/ Dry northwest flow will be the theme this weekend as the strong upper low over the Ohio River Valley continues to shift eastward. Expect another brisk afternoon today with highs in the low to mid-50s, with much lighter winds out of the northwest at 5-10 mph. Post-frontal wind speeds increase to 15 mph as yet another upper low proceeds through the Great Plains approaching the Ohio River Valley once again.
Latest RAP model has a deep low over lower MI that slides to the lower Great Lakes today while high pressure in south TX slips out over the Gulf of Mexico. Strong storm system tracking east across the Great Lakes region and high pressure moving into the Gulf of Mexico from TX will keep a tight gradient across the waters with very robust winds and rough seas through tonight. The high pressure track across the Gulf Sun then over FL to the Atlantic Mon with veering and diminishing winds.
A bit cooler today behind last night's front, as highs are only expected to warm into the 60s across the area. Much drier and cooler air will move into the region during today.
Though with persistent low clouds over the area, there will not be much of a rebound in temperatures today, with highs only in the low to mid 30s. Moisture is very limited with this system but as it moves into the region there is enough forcing to help saturate the mid-levels and produce some light snow and/or freezing drizzle, depending on how much cloud ice is introduced. Given this, it seems reasonable to mention a mix of snow and freezing drizzle.
Highs will be in the 40s and 50s each day with Sunday being a touch warmer.
It will be dry as high pressure goes by to the south and west. The high will be strong enough to keep it quiet for a couple of days.
The chance for snow showers will continue this morning with a shift in the wind from the west, when orographic lift is likely to accumulate snow in the higher elevations through the period. Most locations will see less than an inch in accumulation, with the ridges being the focal point for higher amounts. Expected snow accumulation in the ridges has warranted a Winter Weather Advisory which will go into effect at 1 PM. Total snowfall accumulation will be 3-5 inches in the highest terrain. In the wake of the exiting upper low, heights will briefly rise and most of the snow shower activity should be confined to the I-80 corridor and ridges with the minor cold advection and westerly winds.
/issued 230 AM CST Sat Jan 16 2021/ Wx map continues to show the large vertically stacked sfc to upper level cyclone over most of the Northeastern U.
Ahead of it is enough warm air that the NBM had very high probability of freezing rain, while soundings in the NAM and GFS had really no indication, with only the MOS guidance giving an occasional 10 percent chance. Since the NBM appears way out and see no evidence in the more deterministic guidance, have added a few hours of a slight chance of freezing drizzle during Sun afternoon if the PoP has reached 25 percent. All of this exacerbated by the freezing precipitation issue.
A ridge axis is positioned across the northern Plains, just upstream of the area. Flow at H85 and H7 has weakened over the last 12hrs as the upper low responsible for our high winds pushed off to the southeast. Looking at forecast soundings, this cooler air aloft looks to be enough to squeeze out a little surface based instability.
Southwest to westerly winds have been gusty across the wind prone areas, likely in response to the upper level disturbance and associated cold front. Sunday and most of Saturday will be similar in terms of sensible weather with a slight warming trend on Sunday ahead of the next cold front and upper level trough. Expect light to moderate snow to develop in the mountains Sunday evening, and then spread across the high valleys and high plains overnight. Continued to increase POP between 30 to 60 percent across the lower elevations of southeast Wyoming, with 80% POP across the mountains.
335 AM CST Sat Jan 16 2021 An upper level Low pressure system will continue to shift eastward into the Ohio Valley today. With the trend expected to continue drifting south towards the I-72 corridor, then a more east/southeast movement as the upper Low continues sliding eastward. but additional snow showers re-develop overnight as a secondary Low pressure system tracks through the Midwest. As the upper Low tracks through the Midwest Sunday, this will continue snowfall throughout much of the region.
We have a weak mid-level ridge axis orientated to the northeast over central California from upper level Pacific ridging centered several hundred miles due west of the Point of Conception. Ridging will continue to remain over the area through a majority of the weekend and will increase the chances of patchy fog in the SJV again on Sunday morning. Now, here is where things get quite complicated and quite honestly I feel we may be getting duped by the guidance as a high amplitude ridge axis develops from California northward well into western Canada. The first is it is advertising a Pacific disturbance to push directly through the ridge axis near the Washington State and Canada border. This would translate down to the lower levels and could see gusts of 75 mph channeled down into the Sierra foothills.
A strong upper level ridge parked offshore the California coast will continue to provide warm and dry conditions for the Golden State again on Saturday. High temperatures regionwide will be well-above middle January climatological normals with parts of the Sacramento Valley making a run for the low to middle 70s this afternoon. Upper level high will remain in place on Sunday with similar temperatures compared to Saturday.
Slightly stronger signals over NW WI were associated with a mix of snow and freezing drizzle.
303 AM CST Sat Jan 16 2021 Today the Lubbock CWA will be situated between an upper level storm near the Lakes Region and upper level high pressure just off the California Coast. Overnight clear skies and light wind will allow temperatures to once again drop below freezing across the entire FA. THE SYNOPTIC PICTURE THIS MORNING IS DOMINATED BY AN INTENSE LOW ACROSS THE OHIO VALLEY AND RIDGING ALONG THE WEST COAST.
An upper trough moving across the CWA early today is rather weak and any precipitation will be falling out of a 8-10kft mid deck which has a substantial dry layer below it, so virga is all that is anticipated.
242 AM PST Sat Jan 16 2021 High pressure will remain overhead through this weekend with mainly light winds, weak to moderate inversions, and mild temperatures.
The low that is responsible for this will continue to track east.
Temperatures continue to hover around freezing, which is causing precipitation types to switch back and forth at times, particularly across the east. Highs on Sunday are expected to be a bit cooler, but still above normal, ranging from the middle 20s across the north with lower 30s across east-central Wisconsin.
410 AM CST Sat Jan 16 2021 Today and tonight: The low pressure system was moving through the mid south with very little impact to the CWA. Looks like there could be more breezy conditions across the north, mainly along the highway 82 corridor today.
Kept the gusts in at GWO and GTR late morning through this afternoon as the upper low continues to move away. Today and tonight: The low pressure system was moving through the mid south with very little impact to the CWA. Looks like there could be more breezy conditions across the north, mainly along the highway 82 corridor today.
A low amplitude ridge of high pressure will be over the Northern Rockies today with a few very light showers lingering across extreme northwest Montana.
640 AM EST Sat Jan 16 2021 A deep upper trough will dominate the eastern half of the country during the short term. A couple of short waves will move through the trough across the southern Appalachians.
Additionally, localized shoreline confluence caused by a narrow tongue of stronger winds along the backside of the low may also provide a modest boost to snow rates in northwest Indiana.
Latest upper air analysis shows the closed low now over the Ohio River Valley. To the west a ridge was building in. A short wave trough was moving in the northwest flow onto the Plains. Accompanying this trough is increased cloud cover and some isolated light precipitation. Today the upper level short wave trough will move through the forecast area during the morning. Confidence is low that any precipitation will occur due to the weak lift associated with the trough. Highs will be warmer than yesterday due to WAA, with temperatures reaching the mid 40s to low 50s. During the night a weak cold front will move through the forecast area. There will be weak WAA during the day, which will help offset the colder air behind the cold front. Highs will be slightly cooler than today, warming into the 40s.
Upper level analysis places low moving over the Ohio River Valley with ridge off the west coast. For today, some fog has developed in the calm winds under the high over parts of western/central North Dakota.
Best accumulating snowfall will occur on the higher northwest facing slopes, where orographics will help the snowfall to linger the longest, in spite of the developing subsidence this afternoon.
SHORT TERM (Today through Sunday): Surface observations suggest that temperatures near freezing are developing over portions of the northern ranchlands. In the middle layers of the atmosphere, the passage of a weak trough on Sunday will produce isolated showers over the southeast corner of the BRO CWFA and nearshore coastal waters, especially the Laguna Madre.
A low amplitude ridge of high pressure will be over the region today. KGPI will be dealing with the low stratus with periods of very light snow. A low amplitude ridge of high pressure will be over the Northern Rockies today with a few very light showers lingering across extreme northwest Montana.
/issued 221 AM CST Sat Jan 16 2021/ A deep cut-off low over the Mid-Mississippi River Valley drove a strong cold front into the area yesterday. Surface ridging that was overhead yesterday will shift east today with southerly flow returning to the area. Another cold front is due to arrive this evening, but you won't notice much change behind this front.
For the most part the lower levels remain too dry to support snow, but a brief period of light snow here and there not out of the question, with the better chances in south central SD late this afternoon into the evening. Winds will gust to around 20 to 25 mph at times today which might cause some minor blowing and refreezing in open areas, but without much sunshine not sure just how much melting will occur.
This storm system has been on the warm side with surface temperatures at midnight in the lower to mid 30s. Precipitation in many locations was light rain or drizzle, with colder spots and ridges experiencing light snow. The 500mb low per heights and water vapor satellite shows the impressive cyclone that was over the forecast area had finally shifted southeast and was near the borders of IL/IN/KY. Cyclonic flow and weak warm air advection continues this morning as an area of low pressure over Michigan pivots and gradually shifts into Ohio.
326 AM CST Sat Jan 16 2021 High pressure currently building over the area with some light freezing temps during the overnight mainly for northshore areas over teh weekend.
VFR conditions are expected through the next 24 hours, with surface winds veering due to high pressure shifting east. /issued 342 AM CST Sat Jan 16 2021/ SHORT TERM (Today through Sunday): Surface observations suggest that temperatures near freezing are developing over portions of the northern ranchlands. In the middle layers of the atmosphere, the passage of a weak trough on Sunday will produce isolated showers over the southeast corner of the BRO CWFA and nearshore coastal waters, especially the Laguna Madre.
544 AM CST Sat Jan 16 2021 An upper level Low pressure system will continue to shift eastward into the Ohio Valley today. With the trend expected to continue drifting south towards the I-72 corridor, then a more east/southeast movement as the upper Low continues sliding eastward. but additional snow showers re-develop overnight as a secondary Low pressure system tracks through the Midwest. As the upper Low tracks through the Midwest Sunday, this will continue snowfall throughout much of the region.
517 AM CST Sat Jan 16 2021 (Today and tonight) Early this morning, water vapor satellite imagery shows a large upper level low moving east over the Ohio Valley while northwest flow aloft continues over West Central Texas. This, in addition to sunny skies and strengthening of the 850 mb thermal ridge, will lead to warming today, with highs in the low to mid 60s. Expect lows in the low 30s.
Deepening low pressure across the eastern CONUS will support breezy northwest winds areawide Sunday.
420 AM EST Sat Jan 16 2021 The cold front moved through the Keys island chain overnight as expected, preceded by brief heavy downpours at some locations. Satellite imagery depicts a massive gyre spinning over the Midwest and anchoring a large trough which dominates the entire eastern half of the CONUS. An active subtropical jet streaking to the south of this trough continues to bring high cloudiness over the Keys and South Florida. For today, expect partly cloudy, dry and slightly cooler conditions, as northwest winds gradually diminish during the day.
Some of the high-resolution models are showing some weak potential reflectivity tonight across the north and the Canadian model actually squeezes out a hundredth of two of QPF, so we may see some virga or perhaps localized light rain, but the odds of getting measurable precipitation to the ground looks less than 20 percent so will keep the mention of precip out of the forecast for now.
A weak cold front will shift winds to the north around 00Z. /issued 303 AM CST Sat Jan 16 2021/ Today the Lubbock CWA will be situated between an upper level storm near the Lakes Region and upper level high pressure just off the California Coast. Overnight clear skies and light wind will allow temperatures to once again drop below freezing across the entire FA. THE SYNOPTIC PICTURE THIS MORNING IS DOMINATED BY AN INTENSE LOW ACROSS THE OHIO VALLEY AND RIDGING ALONG THE WEST COAST.
/Today through Sunday/ Dry northwest flow will be the theme this weekend as the strong upper low over the Ohio River Valley continues to shift eastward. Expect another brisk afternoon today with highs in the low to mid-50s, with much lighter winds out of the northwest at 5-10 mph. Post-frontal wind speeds increase to 15 mph as yet another upper low proceeds through the Great Plains approaching the Ohio River Valley once again.
Otherwise, mid-level ridging is expected to briefly build in later this afternoon and giving southern WI a reprieve from the light snow this evening before another mid-level trough digs across the Upper Midwest overnight.