Aikyam-Lab/Synoptic-Bench huggingface dataset:
All in all a cooler day than yesterday with highs in the 30s to mid 40s. Expecting the bulk of precipitation with this system will stay well to our south overnight, and forecast soundings show a persistent layer of dry air in the low levels. The area will continue to be under the influence of surface ridging on Saturday, with highs expected to be in the 30s to around 40, near to slightly below normal for this time of year.
Latest short range guidance is in good general agreement on the lowest visibilities remaining confined to this area with just patchy light fog possible elsewhere so no changes were made to the dense fog advisory that was previously issued.
435 AM MDT Fri Mar 13 2020 A surge of deep subtropical moisture began to move over the southern portion of the forecast area early this morning ahead of a closed mid-level low pressure system centered over the southern California coast. Rain and snow will increase and spread north during the day as the low travels northeastward across Arizona and evolves into an open wave around midday. Meanwhile, 7H temperatures ranging from 0 to +1 deg C initially continue to favor accumulations mainly above the 8500 foot level with rain in across the lower elevations. The open wave trough pushes across the forecast area this evening with subsidence settling over the area in its wake.
The period begins with an area of low pressure crossing the region. The low will bring accumulating to snow North Dakota, and locations along and north of Highway 212 in this CWA.
546 AM MDT Fri Mar 13 2020 Split flow pattern continues with upper low along the southern CA coast and active west-northwest flow aloft across northern half of the CONUS. A cold front extended from southwest MT through central SD into northern WI. South-southeast upslope flow along the Cheyenne Ridge is producing areas of freezing fog and drizzle. WYDOT webcams indicated very low visibilities across the South Laramie Range Foothills, and this zone was added to the Freezing Fog Advisory valid until Noon MDT. Short range models/ensembles remain in good agreement with the CA upper low transitioning to an open wave and lifting northeast across the central/southern Rockies and High Plains later this afternoon and tonight.
Warm and dry conditions again today, as a low level ridge persists over the area. Highs will warm into the mid to upper 80s this afternoon at interior locations, while coastal areas will be capped in the low 80s due to a seabreeze forming late this morning and early afternoon. Favorable boating conditions today, as high pressure persists over the area.
654 AM CDT Fri Mar 13 2020 /12Z TAFS/ Scattered showers and thunderstorms will continue to develop intermittently throughout the day and tonight as a cold front moves slowly south through the area, and upper level energy moves through the area. A cold front will move south into the area today. After these early morning thunderstorms, we may see some showers and isolated thunderstorms later today/this afternoon, along with mostly cloudy skies, and cooler temperatures. This combined with the cold front, and increasing instability during the afternoon hours, is expected to bring another round of thunderstorms through the area late this afternoon into the evening hours.
1041 AM EDT Fri Mar 13 2020 High pressure nosing in from the west northwest making for a nice day today. The cold front is pushing through the Lake Cumberland region early this morning, where a narrow rain band is moving east. Temperatures will fall into the 40s to lower 50s this morning behind the front, but recover slightly into the low to mid 50s this afternoon under partly to mostly sunny skies. Tonight, low amplitude ridging will remain in place aloft. Weak low pressure will develop eastward over the southern Plains. An elevated warm front will lift back north over the region early Saturday, helping to saturate the mid levels.
550 AM MDT Fri Mar 13 2020 Split flow pattern continues with upper low along the southern CA coast and active west-northwest flow aloft across northern half of the CONUS. A cold front extended from southwest MT through central SD into northern WI. South-southeast upslope flow along the Cheyenne Ridge is producing areas of freezing fog and drizzle. WYDOT webcams indicated very low visibilities across the South Laramie Range Foothills, and this zone was added to the Freezing Fog Advisory valid until Noon MDT. Short range models/ensembles remain in good agreement with the CA upper low transitioning to an open wave and lifting northeast across the central/southern Rockies and High Plains later this afternoon and tonight.
High pressure is making its way south into the area this morning, bringing in colder temperatures. Low this morning will drop into the low 30s across our northern counties and mid to upper 30s in our southern counties. The closed low currently over the southwest U. This is where temperatures will drop to near freezing. With the ground being relatively warm and the temperatures hovering just above freezing, the grassy and elevated surfaces will see the most snow accumulations, but some minor accumulations on roadways is eventually possible as well. Some sleet may also mix in around the MO River as the 850 mb warm front moves north. There is still some uncertainty with temperatures and if they end up a little cooler than forecast, that would result in more snow accumulation.
417 AM CDT Fri Mar 13 2020 An exiting low pressure system will leave a few residual snow showers across the Northland this morning, but the gusty winds may be the bigger story - though they will be on the decrease through the day. The pressure gradient that the Northland finds itself in this morning is a combination of high pressure building to the west and low pressure to the east. This gradient should relax as high pressure becomes more dominant. Clouds will be fairly persistent until the high pressure arrives tonight. High pressure lingers through most of Saturday for a quiet and seasonable day.
An upper level ridge now centered over the extreme western Gulf of Mexico continues to push eastward. Low level mean layer ridge (925-700 mb) is taking shape across the eastern Gulf and the Florida Panhandle. Moisture will be limited in the low levels but will continue to be enough to spark some showers mainly in the Florida Straits. Temperatures will remain above normal with daytime highs in the lower to mid 80s and overnight lows in the lower to mid 70s. A ridge axis extending from the western North Atlantic through Florida will remain in place for the next few days.
/Issued 459 AM EDT Fri Mar 13 2020/ The short term period begins with high pressure aloft in the Gulf of Mexico keeping the local forecast area in nearly zonal flow aloft. A cold front was located just north of the local forecast area. Broad/flat upper ridge centered over the central GOM will shift south during the period allowing moderately strong westerlies to dip further into the southern states.
Ceilings and visibilities may be restricted for a few hours this morning by a few showers just ahead of a cold front. Cold front over middle Tennessee is providing the lift for scattered to numerous showers moving into the eastern part of Tennessee as showers from earlier convection that moved southeast from eastern KY late in the evening along a warm front that were widespread a few hours ago have now reduced to more scattered to widely scattered over northeast Tennessee and southwest Virginia. Temperatures now are in the mild lower to mid 60s and should stay nearly steady ahead of the cold front as southwest winds should stay around 10 to 15 mph with higher gusts during the early morning hours.
449 AM MDT Fri Mar 13 2020 Northwesterly flow aloft will become southwesterly today as an upper trough approaches the region from the southwest. At the surface this will translate into a tight surface pressure gradient over the forecast area with gusty southeasterly winds developing between high pressure to the east and low pressure to the west. Precipitation will move northward into southwestern and south central South Dakota this afternoon and evening, beginning first as rain over the lower elevations then turning to snow as temperatures cool this evening. Decent lift aloft combined with easterly upslope flow in the lower and mid-levels will combine to support heavy snow accumulations, mainly over the eastern slopes of the Black Hills and the adjacent foothills.
More sun to the east should allow slightly warmer highs across the pine treed portion of the FA, from Baudette to Bemidji to Park Rapids.
602 AM CDT Fri Mar 13 2020 Updated for 12Z aviation discussion 12Z TAF discussion: The weak cold front has moved through GLH but not GWO at 11Z so MVFR and -RA has been slower to move south of the HWY 82 corridor. Model consensus suggests the cold front will stall across the central portions of our CWA this afternoon with the greatest chance for rain along and north of the stalled front. Temperatures will be cooler than normal today north of the cold front but continue well above normal across our southern zones. Warmer than normal temperatures are expected areawide tonight.
Still expect rain to spread across the area tonight as strong warm air advection sets up ahead of the trough. Expect lows tonight to be at or just above freezing in these areas with the rest of the area in the mid 30s. Do expect the precipitation to slowly move out from northwest to southeast during the afternoon and evening as the NAM/GFS shows the trough moving off to the east.
Weak ridging over the Coastal Bend will slide off to the east today as an upper low over the southwest moves into the southern Plains, weakening as it does so.
A cold front will move south into the area today. After these early morning thunderstorms, we may see some showers and isolated thunderstorms later today/this afternoon, along with mostly cloudy skies, and cooler temperatures. This combined with the cold front, and increasing instability during the afternoon hours, is expected to bring another round of thunderstorms through the area late this afternoon into the evening hours.
537 AM MDT Fri Mar 13 2020 A surge of deep subtropical moisture began to move over the southern portion of the forecast area early this morning ahead of a closed mid-level low pressure system centered over the southern California coast. Rain and snow will increase and spread north during the day as the low travels northeastward across Arizona and evolves into an open wave around midday. Meanwhile, 7H temperatures ranging from 0 to +1 deg C initially continue to favor accumulations mainly above the 8500 foot level with rain in across the lower elevations. The open wave trough pushes across the forecast area this evening with subsidence settling over the area in its wake.
523 AM MDT Fri Mar 13 2020 Northwesterly flow aloft will become southwesterly today as an upper trough approaches the region from the southwest. At the surface this will translate into a tight surface pressure gradient over the forecast area with gusty southeasterly winds developing between high pressure to the east and low pressure to the west. Precipitation will move northward into southwestern and south central South Dakota this afternoon and evening, beginning first as rain over the lower elevations then turning to snow as temperatures cool this evening. Decent lift aloft combined with easterly upslope flow in the lower and mid-levels will combine to support heavy snow accumulations, mainly over the eastern slopes of the Black Hills and the adjacent foothills.
632 AM EDT Fri Mar 13 2020 A fast moving cold front will bring rain showers to central Pennsylvania this morning. A gusty west flow of much drier air will follow the cold front.
An exiting low pressure system will leave a few residual snow showers across the Northland this morning, but the gusty winds may be the bigger story - though they will be on the decrease through the day. The pressure gradient that the Northland finds itself in this morning is a combination of high pressure building to the west and low pressure to the east. This gradient should relax as high pressure becomes more dominant. Clouds will be fairly persistent until the high pressure arrives tonight. High pressure lingers through most of Saturday for a quiet and seasonable day.
/issued 344 AM EDT Fri Mar 13 2020/ Upper level ridging will slowly build east across the Gulf of Mexico today through the weekend. At the surface, Atlantic ridging extending across the Florida Peninsula today will be reinforced from the north tonight and Saturday as a weak cold front washes out north of Florida. Under this ridging both at the surface and aloft, strong subsidence will favor a warm and stable airmass.
The cold front is pushing through the Lake Cumberland region early this morning, where a narrow rain band is moving east. Temperatures will fall into the 40s to lower 50s this morning behind the front, but recover slightly into the low to mid 50s this afternoon under partly to mostly sunny skies. Tonight, low amplitude ridging will remain in place aloft. Weak low pressure will develop eastward over the southern Plains. An elevated warm front will lift back north over the region early Saturday, helping to saturate the mid levels.
A cold front is located across the Tennessee River Valley this morning and is pushing further south and east towards the forecast area. Expect a few isolated showers ahead of the cold front this morning with some increase in coverage during the afternoon. The cold front will stall south of the forecast area over southern Georgia on Saturday with generally zonal westerly flow aloft. Forecast soundings and time heights indicate abundant moisture in the lower levels so mostly cloudy skies are expected.
Highs will range from the lower 50s north to approaching 70 TN/AL border region.
221 PM CDT Fri Mar 13 2020 Things will remain quiet through the short term, with seasonable temperatures and dry weather as a ridge of high pressure drops in from the northwest then slowly slides east through the weekend.
Calm conditions expected throughout the weekend as the high pressure lingers over the Northland. Partly sunny skies are forecasted for the region as a swath of mid and upper level moisture trails behind the exiting low pressure system towards Quebec. Light winds will prevail across the area and high temperatures are expected to hover around freezing.
And don't expect any major changes to the expected high temperature today with much of the area getting into the low to even mid 80s.
A cold front is located across the Tennessee River Valley this morning and is pushing further south and east towards the forecast area. Expect a few isolated showers ahead of the cold front this morning with some increase in coverage during the afternoon.
As the high develops north of the area, and then shifts east through tonight, will see wedge develop in the Carolinas. The pattern remains the same with the forecast area under a general westerly flow aloft as high pressure persists over the Gulf.
The lowering CIGs may help contribute to lowering VSBYs toward VCT late in the night as well, although due to winds to remain slightly elevated, have not gone lower than MVFR VSBYs at this time.
1042 AM MDT Fri Mar 13 2020 A surge of deep subtropical moisture began to move over the southern portion of the forecast area early this morning ahead of a closed mid-level low pressure system centered over the southern California coast. Rain and snow will increase and spread north during the day as the low travels northeastward across Arizona and evolves into an open wave around midday. Meanwhile, 7H temperatures ranging from 0 to +1 deg C initially continue to favor accumulations mainly above the 8500 foot level with rain in across the lower elevations. The open wave trough pushes across the forecast area this evening with subsidence settling over the area in its wake.
121 PM CDT Fri Mar 13 2020 Isolated showers continue this afternoon behind a cold front that has pushed south of our region. Temperatures will continue to drop into the low 50s, potentially upper 40s, by early tomorrow morning. Strong ridging over the Gulf of Mexico will continue through the short term period as a cutoff low over the Baja Peninsula region lifts to an open wave and traverses the Southern Plains. The Gulf ridging will approach near-record heights at 500 mb, but due to the stalled boundary, the warmer temperatures will remain elusive this time around.
259 PM MDT Fri Mar 13 2020 Satellite imagery nicely illustrates the position of today's low pressure system and its cyclonic circulation, currently spinning in east-central Utah. The upper-level closed low will continue to break into an open wave, sliding northeast across the CWA this evening. The next low pressure system spinning off the Pacific NW and its southerly track will help maintain a warming trend over the next several days, with minimal chance for precipitation. Anticipate above average temperatures, climbing another 5 to 10 degrees warmer by midweek with seasonable overnight lows.
The eastern portions of the central and southern Black Hills, esp the Custer State park to Hill City area will see up to 12 inches of snow, with 5 to 9 inches from the higher elevations of the foothills zones west seeing warning level snows.
As for Saturday, with the warm front lifting ever farther north into eastern OK to the Mid- Mississippi Valley, only limited rain chances are expected within our CWA. With ridging over the region, the best chances for this activity will remain across the northern part of the forecast area.
Low temperatures Tonight will be in upper 50s to lower 60s, with high temperatures Saturday in the lower-mid 80s inland se GA, mid- upper 80s inland ne FL, near 80 coast.
216 PM EDT Fri Mar 13 2020 High pressure will build across the Commonwealth tonight and Saturday, to bring diminishing winds, and seasonable temperatures.
Temperatures in the lower and mid 30s north of Interstate 94 and ranged from the mid 30s to mid 40s across the remainder of the area.
A mix of rain and snow is expected mainly south of Route 24 on Saturday, with no impacts expected as highs will be above freezing. Generally clear skies have allowed highs to climb into the 40s this afternoon, but we will see temps fall back near freezing for the night before clouds increase from the south in advance of the next wave passing mainly south of the area.
Surface analysis places a cold front from the Appalachians back through Central Alabama/Mississippi, Northern Louisiana then back into Eastern Texas. Regional WSR-88D radar trends indicate light returns over the Mid-South but likely not reaching the ground while rain showers are occurring further west over western sections of the Lower Mississippi Valley. As of 3 PM CDT, temperatures across the area are in the 50s at most locations except over North Mississippi where temperatures are currently in the lower 60s. Short term models and radar/observational trends indicate rain showers will gradually return to the Mid-South tonight as the aforementioned cold front moves back north as a warm front Saturday into Saturday night.
Storms and attendant threats will largely be determined by a cold front that will be located INVOF Pecos River and its potential to move n as a warm front into the overnight. We are also concerned that instability could be maximized in the Lower Trans Pecos and the Big Bend area, there are lots of vacationers down at BBNP and we have increased PoPs there. The cold front will surge back s late Sat night-Sun AM setting up SUN PM to possibly be much cooler (NAM12 has highs in the 40s for much of the PB!).
It will be dry today as southwest flow aloft develops ahead an approaching upper low pressure system.
A cold front currently located just north of the county warning area will stall this evening over the far north portion of the area, north of Highway 84. Fog will dissipate by mid Saturday morning with a warm and dry day in store as upper ridging continues to build across the region (594 DM high forecast to be centered over the central Gulf tomorrow. ) Highs will climb into the low to mid 80s inland with mid to upper 70s closer to the coast, influenced by a light onshore wind over the cooler marine waters.
Water vapor satellite today shows our upper level low pressure has moved onshore in southern California. This trough has pushed eastward today and will be our main weather maker as we head into the weekend. Our morning sounding at Omaha shows a significant dry layer in the low levels, which is going to take some time to saturate this afternoon. with a warmer ground and above freezing weekend temperature, we can expect quite a bit of melting and compaction as the snow falls friday night into saturday.
Currently, a wealth of dry air in place with dew points in the lower 20s.
1234 PM CDT Fri Mar 13 2020 (Today and tonight) Surface front will stall across north Texas today with much cooler and somewhat drier air filtering south in the lower levels. Meanwhile, a few thousand feet aloft strengthening WAA will develop along with forcing from approaching upper trough will result in increasing rain chances across north Texas and Oklahoma through the day today. Cold front begins to retreat back north tonight as a warm front.
Upper trof over Arizona will move northeastward over the central/southern Rockies early tonight, then across the central Plains thru early Saturday. Surface temperatures are also expected to stay at or just above freezing early Saturday morning across the higher terrain of central Kansas. A brief period of light freezing rain is also possible, if temperatures can drop to freezing.
(This evening through Saturday) A cold front over central Texas will stall this evening, then move slowly north as a warm front into tomorrow. Lots of moisture flowing northeast over the low-level cold air will bring widespread rain to the region tonight and tomorrow.
Chattanooga Airport, TN 48 65 54 64 49 / 20 60 90 70 20 Knoxville McGhee Tyson Airport, TN 44 58 48 59 48 / 10 80 90 60 10 Oak Ridge, TN 44 57 47 59 46 / 10 80 100 50 10 Tri Cities Airport, TN 40 54 44 54 43 / 10 80 100 50 20.
/issued 654 AM CDT Fri Mar 13 2020/ /12Z TAFS/ Scattered showers and thunderstorms will continue to develop intermittently throughout the day and tonight as a cold front moves slowly south through the area, and upper level energy moves through the area. A cold front will move south into the area today. After these early morning thunderstorms, we may see some showers and isolated thunderstorms later today/this afternoon, along with mostly cloudy skies, and cooler temperatures. This combined with the cold front, and increasing instability during the afternoon hours, is expected to bring another round of thunderstorms through the area late this afternoon into the evening hours.
428 PM EDT Fri Mar 13 2020 Low clouds cleared out today as a cold front dropped well south of the region, and ridging began to build in from the west. Model data shows temps getting down near freezing Saturday night before precip winds down, especially over the northern end of the forecast area. Should anyone hit freezing, it would result in freezing rain.
High pressure will remain over the Western Atlantic waters through early this weekend keeping a stationary front over the Southeastern United States.
117 PM EDT Fri Mar 13 2020 A cold front will make its way east across the area this morning.
Between these two features, a cold front was oriented west to east across the southern half of AR. Along this slow moving cold front, stratiform precipitation continues to develop and move adjacent the boundary. A closed low over the four corners region will pivot out over the Rockies today as upper ridging remains firmly in place over the Gulf of Mexico. The surface front will become stationary as forward progress halts and begin to lift northward as a warm front. On Saturday, another cold front will move towards the state from the Plains. Rainfall will taper off from north to south during the overnight hours on Saturday as high pressure approaches the region.
With the low level wind profiles, there will be opportunity for rotating storms which could produce hail.