Aikyam-Lab/Synoptic-Bench huggingface dataset:
Low clouds and reduced visibilities will continue to lift throughout the day as the high pressure frontal boundary recedes off towards the northeast. Overnight low temperatures will drop into the lower to mid 50s for southeast Georgia and into the mid to upper 50s for northeast Florida.
Storms are expected to develop sometime Friday evening along or just ahead of the cold front as it approaches the mid Mississippi Valley.
128 PM CST Thu Dec 9 2021 Broad westerly flow aloft this afternoon over the central plains while the positively tilted upper trough digs into southern CA. The highlight of the forecast centers around this system, progged to develop a winter storm over the northern plains tomorrow. Depending upon the cloud cover depth and timing of the incoming cold front, high temps over east central KS may vary from the low 60s to the upper 60s. The main upper trough and poignant cold front arrive into north central Kansas by late afternoon, introducing low chance pops for areas generally north of Interstate 70 through the early evening as temps in the 40s quickly drop below freezing behind the front. Light rain switching to all snow remain possible with the highest chances north of I-70.
1238 PM CST Thu Dec 9 2021 (Today and tonight) The warm-up will continue today as southerly winds bring warmer air into the region.
246 PM EST Thu Dec 9 2021 A stationary front positioned just to the north of Lake Okeechobee will retreat to the north as a warm front later today, with a ridge of high pressure strengthening over the southern and eastern United States the remainder of the week. CIMMS layer mean wind shows a robust high pressure across the Gulf of Mexico and Florida. The high will continue to influence the local weather over the next several days by promoting subsidence throughout the atmospheric column and inhibiting rising motion needed to induce afternoon convection.
In the upper levels, a trough axis was moving through the Northern Plains into the Upper Mississippi, while somewhat of a neutral mid-level height tendency followed. While a trough will begin to plunge through the southwest CONUS and then into the Central Plains, flow aloft to the north will be relatively weak and lead to a relatively diffuse surface pressure pattern over North Dakota while a winter storm impacts southern South Dakota through Friday. The majority of the forecast period into mid-week remains dry with seasonably warm temperatures as a broad ridge builds over the central and eastern US.
119 PM EST Thu Dec 9 2021 High pressure for today.
332 PM EST Thu Dec 9 2021 High pressure will move offshore tonight.
A strong low pressure system will track across Kansas late tonight and Friday, before turning northeast and tracking to the Great Lakes region by late Friday night. There are still some minor model differences as to how far north the snow will get, but they are in decent agreement that the most likely area for accumulating snow will generally be along and south of Highway 212, with the highest overall amounts along and south of Intrastate 90.
Areas of fog can be expected in the Gulf waters well north of the Lower Keys and the Dry Tortugas.
The trough and surface system are still out over the eastern plains of Colorado and New Mexico.
Upper ridging to kick in over the weekend, resulting in continued dry conditions and a warming trend. The degree of warming will always be affected by elements such as depth of snowpack, but by Sun afternoon we will be looking at 850 mb temps up to +4 C and a good west to southwest wind, so would think the area in general should be able to rise a bit above freezing, with a shot at some low 40s near the ND/SD border.
Expect highs tomorrow to settle into the lower to mid 80s, which remains well above normal for this time of year and potentially breaking records again on Friday.
the better shot for convection will come beyond this TAF period as a cold front drops SE through the region.
Fog is expected to increase in coverage after midnight, with the highest density remaining west of I-95. Above average nighttime temperatures look to continue, with lows remaining in the low to mid-60s. Otherwise, the ridge axis from high pressure near the Canadian Maritimes will extend south and west over the W.
A secondary line will develop along the cold front and move into the region around midnight.
831 PM EST Thu Dec 9 2021 Light precipitation is possible tonight and Friday in association with a warm front.
517 PM EST Thu Dec 9 2021 Light precipitation is possible tonight and Friday in association with a warm front.
137 PM PST Thu Dec 9 2021 Cloudy and cool as a cold front moves through the region, with increasing showers this afternoon. WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO Cloudy and cool with increasing showers this afternoon as a cold front moves in from the northwest. A post-frontal trough will move through the region on Friday with little or no noticeable effects, followed by weak ridging for Sat and Sun between low pressure systems.
701 PM EST Thu Dec 9 2021 Yesterday's weak front already washed out and pulled into the W Atlantic earlier today with weak and stagnant high pressure building back into the area from the Mid Atlantic keeping the very moist airmass in place. /issued 211 PM EST Thu Dec 9 2021/ Mid level ridging in the central Gulf of Mexico shifts eastward toward Florida through the end of the week and into the weekend. The surface reflection is broad high pressure that extends from the mid- Atlantic states southwest into the eastern Gulf of Mexico.
555 PM EST Thu Dec 9 2021 Light precipitation is possible tonight and Friday in association with a warm front.
The cold front associated with this ridge is currently draped over northwest Missouri, and will continue to sag southward through the overnight hours tonight, but will hang up a little north of I-70 as the ridge only clips the area. North of the warm front temperatures will struggle to make 50 degrees, and will see winds out of the east. In the midlevels a very strong mid level trough will carve into the flow, and will bring some lift that will also help with precipitation production.
Winds will gradually weaken this afternoon and shift to the east ahead of a low pressure system that will impact the forecast area tomorrow. Snow is the primarily precipitation type expected, but there is some potential for freezing drizzle (discussion below) across eastern Nebraska.
Surface winds will be mostly out of the southwest through the day tomorrow ahead of a cold front passage. The low is then expected to deepen as it pushes east towards southern Kansas. A cold front will push into the region as the upper trough moves across the FA late tomorrow evening.
Broad westerly flow aloft this afternoon over the central plains while the positively tilted upper trough digs into southern CA. The highlight of the forecast centers around this system, progged to develop a winter storm over the northern plains tomorrow. Depending upon the cloud cover depth and timing of the incoming cold front, high temps over east central KS may vary from the low 60s to the upper 60s. The main upper trough and poignant cold front arrive into north central Kansas by late afternoon, introducing low chance pops for areas generally north of Interstate 70 through the early evening as temps in the 40s quickly drop below freezing behind the front. Light rain switching to all snow remain possible with the highest chances north of I-70.
Minor changes were made to near term sky cover with the arrival of mid to upper level cloud cover across the southwest in association with the low pressure system bringing winter weather to to Central Plains overnight. In the upper levels, a trough axis was moving through the Northern Plains into the Upper Mississippi, while somewhat of a neutral mid-level height tendency followed. While a trough will begin to plunge through the southwest CONUS and then into the Central Plains, flow aloft to the north will be relatively weak and lead to a relatively diffuse surface pressure pattern over North Dakota while a winter storm impacts southern South Dakota through Friday. The majority of the forecast period into mid-week remains dry with seasonably warm temperatures as a broad ridge builds over the central and eastern US.
A low chance for freezing drizzle exists but at this time its duration looks too low to cause any impacts. This may lead to a brief window for freezing rain. Based on the low level warm air advection surface temperatures will likely climb above freeing fairly quickly Friday afternoon/evening. however with the low lifting northeast the deeper moisture may struggle to work its way in from the west. the surface temperatures remain largely above freezing Saturday which will also limit the impact risk. As low pressure moves toward Michgian today, low level moisture will increase rapidly this afternoon.
After sunset, late in the TAF period winds will begin to increase as a strong cold front moves closer to the region. McD Chattanooga Airport, TN 49 65 63 69 34 / 60 60 40 100 0 Knoxville McGhee Tyson Airport, TN 45 65 60 69 32 / 40 60 30 100 0 Oak Ridge, TN 44 64 59 68 30 / 50 50 40 100 0 Tri Cities Airport, TN 38 62 53 68 29 / 40 30 20 100 10 TN.
Colder air noted upstream across southwest ID in RAP analysis, characterized by 700mb temps in the -14 to -15C range, will spread southeast overnight, increasing instability over warmer water bodies and increasing the potential for additional convection overnight.
A secondary line will develop along the cold front and move into the region around midnight. High pressure will begin to settle in over the area with temperatures dropping to the mid 20s to low 30s by Saturday night.
Some minor areal flooding of poor drainage areas cannot be ruled out tonight where rainfall exceeds an inch in short duration, but the mainstem rivers should be able to handle the higher amounts given current low levels. Still cant rule out an hour or two of snow and freezing rain along the U.
but as a cold front drops SE into the state. the better shot for convection will come beyond this TAF period as a cold front drops SE through the region. Working for it would be if convection and initiation is already happening by sunset, low level jet dynamics kicking in, as well as significant speed shear present in the lower levels. Precip will end during the morning Saturday, with high pressure moving in on northwest flow aloft, and colder temperatures again (though if I were you, I wouldn't get used to that, unfortunately).
In addition, models show the warm front associated with tomorrow night's system pulling northward through the mid-state tomorrow morning. Aft 00z, Cold front will be moving across MO.
An upper level trough that is currently located over the northern Rockies will continue to dig as it approaches the northern Plains. Highs will be around normal for this time of year today, in the lower 20s across the Turtle Mountains to the mid 30s over the southwest.
In addition, models show the warm front associated with tomorrow night's system pulling northward through the mid-state tomorrow morning.
Storms are expected to develop sometime Friday evening along or just ahead of the cold front as it approaches the mid Mississippi Valley. Near-surface lapse rates will remain quite stable until the cold frontal passage late Friday night, then the gradient will slacken on Saturday. Much cooler air will arrive Saturday, with temps nearly steady around 50 despite sunshine. Sub-freezing temps are expected Sat night under clear skies and light winds.
As we go into the weekend a strong cold front will start to develop and push towards the east coast.
After 13Z increasing sunshine will slowly erode the low stratus and fog across the regional terminals with all sites improving to MVFR conditions. VFR conditions will return after 15Z at all sites as high pressure just off the Florida and Georgia coast moves eastward into the Atlantic as a warm front lifts from the Gulf coast north of the regional terminals with southeast winds staying light around 5-8 knots, but rain chances not great enough to include in the TAF package. Low clouds and reduced visibilities will continue to lift throughout the day as the high pressure frontal boundary recedes off towards the northeast. Overnight low temperatures will drop into the lower to mid 50s for southeast Georgia and into the mid to upper 50s for northeast Florida.
Winds will be out of the southwest ahead of a cold front tomorrow that will bring northwest winds to the TAF sites. Some blowing dust is possible through the afternoon hours tomorrow with the higher winds. The low is then expected to deepen as it pushes east towards southern Kansas. A cold front will push into the region as the upper trough moves across the FA late tomorrow evening.
206 AM MST Fri Dec 10 2021 Upper trough will be over the region today which will keep temperatures near to slightly below normal today. Skies will clear from NW to SE across the forecast area today as high pressure moves in. Upper trough moves to the east tonight and upper ridge moves in for the weekend. This will bring warmer temperatures which will allow some of the snow to melt.
947 AM EST Fri Dec 10 2021 Mostly sunny conditions are expected to prevail over the Keys today, as a ridge of high pressure continues to remain anchored above the region. The high is progged to gradually weaken this weekend due to a frontal boundary moving into the Gulf of Mexico and the Florida Peninsula late Saturday night.
Have also retreated a bit from afternoon measurable rain mention as warm frontal encroachment is model-timed for later eve. As a negatively tilted trough develops and pushes east, a strong 150 knot jet streak will take shape at 300MB. Showers will continue to move into the forecast area ahead of the cold front. 4 inches, will precede the cold front. It is worth noting that the higher terrain in Tucker County will likely see a higher speed of wind mix to the surface at 3000 to 4000 for elevations.
419 AM MST Fri Dec 10 2021 The forecast begins with southwest flow aloft over the Tri-State area this morning with a trough entering the Bighorns and the Rockies through the day. As the trough begins to come into the region, we may see a few light snow showers develop in eastern Colorado. Precipitation tapers off this evening from west to east, as the trough moves eastward across Kansas. Saturday, the trough lifts to the northeast and the area comes under northwest flow with a ridge developing to the southwest of the area.
(Today and tonight) Strong southwesterly flow will continue across west and northwest Texas today in response to a low pressure system developing in the lee of the Rockies and will push across Kansas through the day. As a result, we'll see another day of high temperatures in the low 80s, which would break or tie the daily record highs. A cold front will push through the region overnight, shifting winds around to the north and dropping temperatures to around 40 for most locations.
Looking at partly to mostly clear skies and dry conditions for the rest of today, as temperatures climb into the low 80s along the coast and low to mid 80s inland. (Previous Discussion) As the Atlantic ridge becomes a little better defined, boundary layer winds will be slightly stronger out of the E-ESE, which should nudge the threat for dense fog a little farther inland. Mainly clear outside of any fog/stratus with mins in the low to mid 60s.
652 AM EST Fri Dec 10 2021 Low pressure approaches from the west bringing warmer temperatures and a chance for showers today. Showers/storms are likely on Saturday as a cold front passes through the area. Abundant moisture moving ahead of low pressure over the plains will keep clouds streaming overhead through tonight. Shower coverage is expected to increase this afternoon as a stronger wave moves away from the center of the low. A cold front approaches and passes through the region on Saturday bringing likely showers/storms area-wide. Went with a High Wind Watch for the higher terrain of Pocahontas/Randolph counties for Saturday afternoon/evening.
A warm front has lifted north of Middle Tennessee, so we find ourselves in a maritime tropical air mass with a strong low-level jet in the middle of December. Scattered showers are showing up on radar, and due to their random nature, we'll keep VCSH in the TAF's until tonight, when a more organized line of storms develops along a cold front that will move through.
538 AM EST Fri Dec 10 2021 Low pressure approaches from the west bringing warmer temperatures and a chance for showers today. Showers/storms are likely on Saturday as a cold front passes through the area. Abundant moisture moving ahead of low pressure over the plains will keep clouds streaming overhead through tonight. Shower coverage is expected to increase this afternoon as a stronger wave moves away from the center of the low. A cold front approaches and passes through the region on Saturday bringing likely showers/storms area-wide. Went with a High Wind Watch for the higher terrain of Pocahontas/Randolph counties for Saturday afternoon/evening.
348 AM MST Fri Dec 10 2021 The upper level trough over northwestern CO at 12z this morning will track into central NE by this evening, Weak to moderate QG ascent will be over the forecast area through early this afternoon, with increasing QG descent develop this afternoon. In the mountains, west/southwest winds will transition to northwest today in with the passage of the mid level trough axis. Across the urban corridor and northeast plains, the cold front will still expected to push into Denver by 4 am, with north/northwest surface winds developing. With high temperatures near freezing, gusty winds will drop the wind chills into the upper teens/lower 20s across the plains. Spatial cross- sections show strong winds over the higher east slopes developing, with gusts 60-65 mph possible, stronger heading into Saturday.
The heaviest snowfall prior to 18Z will be oriented from south central SD into east central SD and southwestern MN, then shifting to the south and east during the afternoon and becoming heavy as the optimum midlevel frontal band collapses southward and lift increases when the upper level trough moves into the Northern Plains.
546 AM CST Fri Dec 10 2021 (Today and tonight) Strong southwesterly flow will continue across west and northwest Texas today in response to a low pressure system developing in the lee of the Rockies and will push across Kansas through the day. As a result, we'll see another day of high temperatures in the low 80s, which would break or tie the daily record highs. A cold front will push through the region overnight, shifting winds around to the north and dropping temperatures to around 40 for most locations.
545 AM CST Fri Dec 10 2021 Key Points: * Warm front is expected to lift into the region today leading to significant difference from north to south today in terms of high temperatures. * Strong cold front working through the region tonight will lead to brief cool down tonight into Saturday.
453 AM EST Fri Dec 10 2021 Increasing moisture and an approaching cold front will bring rain and windy conditions to the area tonight and Saturday. Pockets of drizzle remain possible this morning as the boundary layer moistens thanks to increasing southwest flow behind the warm front. As a negatively tilted trough develops and pushes east, a strong 150 knot jet streak will take shape at 300MB. Showers will continue to move into the forecast area ahead of the cold front. 4 inches, will precede the cold front. It is worth noting that the higher terrain in Tucker County will likely see a higher speed of wind mix to the surface at 3000 to 4000 for elevations.
400 AM CST Fri Dec 10 2021 Key Points: * Warm front is expected to lift into the region today leading to significant difference from north to south today in terms of high temperatures. * Strong cold front working through the region tonight will lead to brief cool down tonight into Saturday.
This allowed significant radiational cooling to take place, particularly in the larger islands in the Lower Keys, with temperatures reaching close to saturation. Composite water vapor imagery highlights an expansive ridge and associated anticylonic flow over the entire eastern third of the United States. The Storm Prediction Center has placed portions of the Ohio Valley in an enhanced risk for severe weather this evening as the trough pushes eastward. Closer to home, the aforementioned ridge will continue to dominate our forecast for the weekend, with low rain chances and above normal temperatures expected.
A large upper trof advances across the Plains through this evening, then much of the upper trof ejects into the interior eastern states through Saturday while the remaining weaker portion of the upper trof advances more slowly into the south central states.
Thunderstorm chances ahead of the cold front this evening will be quite limited in our area, but did maintain low thunder probabilities mainly in our Arkansas counties.
234 PM CST Fri Dec 10 2021 A sharp upper level low pressure trough and associated very strong layered flow and surface winds will cross east of the area late this afternoon and early this evening. A surface cold front will shove southward with a northwest to northerly wind shift, and cooler air will settle across the region. Highs Saturday are expected to top out in the lower to mid 50s.
(This evening through Saturday) Gusty southwesterly flow will persist through early this evening, along with ongoing dry and warmer than normal conditions as the low pressure system continues to progress eastward. A cold front will push through the region overnight, shifting winds around to the north and dropping temperatures to around 40 for most locations. High temperatures on Saturday are expected to be cooler due to the cold front passage overnight, ranging in the mid 50s to lower 60s.
158 PM MST Fri Dec 10 2021 The forecast begins with southwest flow aloft over the Tri-State area this morning with a trough entering the Bighorns and the Rockies through the day. As the trough begins to come into the region, we may see a few light snow showers develop in eastern Colorado. Precipitation tapers off this evening from west to east, as the trough moves eastward across Kansas. Saturday, the trough lifts to the northeast and the area comes under northwest flow with a ridge developing to the southwest of the area.
No appreciable change was made to the near term forecast as warm, moist advection ahead of low pressure digging toward the Great Lakes will maintain above average temperature and increasing cloud cover through this afternoon, although dry air above the boundary layer will preclude rainfall until the mid levels saturate tonight. The systems sfc cold front is projected acrs the Upr OH latge on Saturday afternoon and early eve. With strongest wind gusts nearing 60mph expected in the highest terrain of ern Tucker County, a High Wind Watch remains in place. Temperature will climb well into the 60s across much of the region within the low's warm sector, possibly nearing record highs in a few instances.
Well above average temperatures and strong gusty winds will be possible ahead of a cold front. *Cooler this weekend.
Temperatures were in the 40s to around 50 early this morning and are only warming slowly due to the lower clouds and light rain. Lower elevations should see highs around 60 with the plateau in the lower 60s, possibly mid 60s. Later this evening downslope winds off the eastern Tennessee mountains should clear the low clouds at TRI and also by morning at TYS.
938 AM CST Fri Dec 10 2021 Cirrus shield from trough to the south covers most of North Dakota this morning, and will exit from northwest to southeast through the day, remaining over the southeast through the evening. An upper level trough that is currently located over the northern Rockies will continue to dig as it approaches the northern Plains. Highs will be around normal for this time of year today, in the lower 20s across the Turtle Mountains to the mid 30s over the southwest.