Aikyam-Lab/Synoptic-Bench huggingface dataset:
Freezing overnight temperatures will occur over the Kern County desert with a freeze possible in parts of the San Joaquin Valley as well, especially later this week. A deep upper cyclone is spinning over Minnesota with a large trough over the Rockies as short wave ridging builds over the west coast. Also, temperatures in the valley may bottom out around freezing in a few locations tonight.
Temperatures will generally be in the low to mid 70s over the east coast and 60s along the interior and west. Strong low pressure system over the upper midwest and its associated front will push across the southeast plains this week while ridge of high pressure continues to hold over the southern portion of Florida. High pressure will keep southeasterly flow across the region before weakening as the front gets closer to the area.
/issued 226 PM CST Tue Nov 29 2016/ A broad upper level trough is over most of the country with the CWA at the south end. Temperatures today are expected to be a little cooler than yesterday as lower heights spread across the region due to the upper trough. A cold front will move through the area tonight in association with the upper trough. Overnight lows will likely reach the freezing point or below for much of the area. On Wednesday, the previously mentioned upper trough will begin to move eastward while another upper low moves over the Pacific Northwest. Temperatures on Wednesday will be cooler than normal with highs mostly in the 50s.
Some mid and high level clouds passing over the area as the upper level ridge over the region pulls off to the east. This is due to an cold front approaching coming onto the coast this evening.
954 PM CST Tue Nov 29 2016 Early afternoon water vapor imagery together with GFS 500mb heights and surface obs show a broad upper level trough across the central Conus, with the center of an upper level low across central Minnesota. Over the next 36 hours this upper level low will slowly meander to the east southeast. we have the Wednesday night upper low to spread east taking the light snow.
549 PM CST Tue Nov 29 2016 Near-vertically stacked potent low pressure system continues to slowly move southeast across southern Minnesota this afternoon with a series of strong vort lobes rotating around the main low. Some moderation in temperatures is likely into the weekend ahead of the next developing western trough. EC and GFS are in fairly good agreement in digging an upper trough over the western CONUS by 12Z Tuesday.
804 PM CST Tue Nov 29 2016 Cold front currently from just north of Mena to near Mountain Home. Increased cloud cover over central and south sections with the cold front slower to move through the state. (ISSUED 551 PM CST Tue Nov 29 2016 ) Another cold front is entering northwest Arkansas at this time. This front will bring cooler and drier air with it. Current model trends keep this out of AR, some additionally showers and isolated storms are possible this afternoon to evening until the upper low pressure trough and cold front push through the region.
Main closed low continues to rotate over Minnesota while a secondary upper trough is centered over New Mexico this afternoon. A much cooler afternoon is in store with strong cold advection with sustained wind speeds at the sfc from 10 to 20 mph. Wind gusts are up to 30 mph, creating wind chill readings from the lower to middle 30s. Areas of low and mid level moisture from the upper low will keep the mostly cloudy skies across the area as highs struggle to reach the lower and middle 40s. Dry and seasonal conditions are expected for the latter half of the week as the mid-level trough lifts northeast across the Great Lakes region and further into Canada. Northwesterly winds will help to keep cooler yet seasonal with highs in the 40s and lows in the 20s.
Main surface cold front stretches from western Iowa to a secondary wave over Missouri, while much of the state sits within a well defined dry slot/axis of warmer air and steep lapse rates aloft stretching up through lower Michigan into Canada. Then, stronger wave/associated forcing will punch up through lower Michigan later in the morning and the afternoon hours as the upstream cold front swings into the region.
Cold front currently moving through SE OK/NW AR with NW winds behind front across NE OK. /Issued 313 PM CST Tue Nov 29 2016/ Broad upper level trough remains over the central U. Cold front currently passing through northeast OK and shifting wind out of the northwest should lead to a bit cooler temps tonight in most locations along with several degree drop in high temps for Wednesday. There will be some increase in fire danger for Wed afternoon despite cooler temps as wind speeds pick up and very dry air remains in place.
Main cold frontal boundary still located back across western AR and extends southwestward into east TX. Meanwhile, the warm front will lift north with a modified triple point setting up just north of TN. Deep cyclone centered over Minnesota this afternoon with 120 knot upper jet from Texas to Pennsylvania will undergo anticyclonic curvature this afternoon and overnight placing Middle Tennessee in the right rear quadrant for several hours which will aid the development of convection. Surface cool front will begin to push eastward from Oklahoma this evening with strengthening low level jet and a northward surge of moisture along with a warm front currently draped west to east across Mississippi and Alabama that will move northward this evening placing Middle Tennessee in the warm sector by mid evening.
A few showers moved over the higher valleys as well, but additional accumulations have been spotty and light. Some of this activity will continue off and on over the northern Colorado mountains tonight through Wednesday night bringing light additional accumulations, mainly to the higher areas.
Convection should eventually end from west to east with the passage of an approaching cold front. South of the front, temperatures in the lower/mid 80s with dewpoints in the upper 60s to lower 70s. After the cold front passage, cooler and drier air will prevail across the region. Cooler than normal temperatures expected for Wednesday night into the weekend.
Strong low pressure system over the upper midwest and its associated front will push across the southeast plains this week while ridge of high pressure continues to hold over the southern portion of Florida. High pressure will keep southeasterly flow across the region before weakening as the front gets closer to the area.
A precipitation-free cold front will slide southward through Metroplex TAF sites over the next 2 hours with FROPA closer to 04 UTC at Waco. Weak ascent atop the cooler air should allow for the development of some mid-level clouds around FL100.
However, this is north of the warm front currently and no rotating cells are indicated by radar as of yet.
Latest surface analysis shows a low across the western Great Lakes with a trailing cold front extending through central Missouri through central Red River Valley. A stationary/warm front was situated generally south of I-20 across AL/MS. The airmass along and south of the warm front was quite juicy this afternoon with dewpoints well into the 60s. For tonight, the initial question is how quickly/how far north the warm front progresses. The upper trough axis will push across by early afternoon ushering in the "cooler" air.
A cold front approaching Wednesday will move through the forecast area Wednesday evening. Much above normal temperatures will lower behind the cold front over the weekend. Overnight lows in the low to mid 60s. The models are in close agreement depicting the approaching cold front moving through the forecast area Wednesday evening. However, instability could become a little greater because of the favorable diurnal timing just ahead of the cold front with near record temperatures climbing to around 80 in some locations. Mixing associated with the front favors the higher minimum temperature guidance.
Chattanooga Airport, TN 64 66 40 57 / 100 100 10 10 Knoxville McGhee Tyson Airport, TN 58 66 41 55 / 80 100 20 10 Oak Ridge, TN 54 66 41 53 / 90 100 10 10 Tri Cities Airport, TN 45 67 39 52 / 30 100 20 10 NC.
As the low level flow gradually veers though, the shower activity should slowly edge off the coast by morning. Marginal to poor boating conds will cont as a hi pres ridge extending from Bermuda thru the FL Straits maintains a steady S/SE sfc/bndry lyr flow acrs the local Atlc.
These scattered storms will be followed by a more solid line of precip associated with a cold frontal passage late Wednesday morning into the early afternoon, which may bring MVFR to IFR conditions to all sites.
834 PM CST Tue Nov 29 2016 Looks like the warm front is now just moving out of our cwa and is heading into mid TN. However with the warm front progged to be out of our cwa overnight, the threat of svr wx should begin to weaken a little after midnight. The upper trough axis will push across by early afternoon ushering in the "cooler" air.
Evening satellite imagery shows a short wave ridge along 120W in WA and OR and a cold front along the Northwest Coast, both moving east. The ridge will pass through our CWA around 12Z and the cold front will bring snow showers to eastern Oregon Wednesday, and western Idaho midday through Wednesday evening.
The upstream cold front remains stalled across the central plains in the deep layer southwest flow pattern due to a strongly positive tilt upper trough from the northern plains into the southwestern states. A cooler and drier airmass will follow in the wake of the front through the day on Wednesday with gradual clearing from northwest to southeast by late afternoon.
851 PM MST Tue Nov 29 2016 Closed low continues to support broad lift and strong ll winds over the region. Lingering snow will slowly end from west to east during the day Wednesday as the low pressure system moves ewd from the upper midwest into the Great Lakes.
551 PM CST Tue Nov 29 2016 Another cold front is entering northwest Arkansas at this time. This front will bring cooler and drier air with it. Current model trends keep this out of AR, some additionally showers and isolated storms are possible this afternoon to evening until the upper low pressure trough and cold front push through the region.
The upper level closed low remained over the Northern Plains this evening with an associated upper level trof axis extending southwest through the Central and Southern Plains. the upper level trof axis will continue to shift east southeast through the Central/Southern Plains and into the CWA by early morning Wednesday. An increase in cloud cover from west to east across Northeast Oklahoma and Northwest Arkansas will be possible as the trof axis moves into the region. will allow for low temps to be slightly cooler for most locations tonight.
This will lead to at least MVFR ceilings/visibilities from Wednesday morning into much of the afternoon as showers expand over area along trough axis between these low pressure centers. Deep upper level circulation now centered over souther Minnesota this afternoon, with positive tilted longwave trough over the Eastern Rockies. This trough axis will become more neutral tilted over the Plains Tomorrow, making for a tough call with respect to rain chances over southeast Michigan with the tightening baroclinic/FGEN zone which looks to be residing in between the Central and Eastern Great Lakes.
926 PM EST Tue Nov 29 2016 A wave of low pressure moves northeastward tonight, pushing a cold front through on Wednesday. Cooler high pressure to end the week. A cold front comes through on Wednesday with a fairly good line and some instability. Some differences still exist in model timing of the cold front, so although there is a high confidence in showers on Wednesday, confidence is lower in the timing. Expecting post frontal precipitation in the northeast mountains, light, with a trace of snow possible in the highest elevations.
944 PM CST Tue Nov 29 2016 Cold front currently along a line from El Dorado to Lufkin. Much cooler temperatures expected by daybreak with portions of southeast Oklahoma dipping below freezing.
708 PM EST Tue Nov 29 2016 A wave of low pressure moves northeastward tonight, pushing a cold front through on Wednesday. Cooler high pressure to end the week. A cold front comes through on Wednesday with a fairly good line and some instability. Some differences still exist in model timing of the cold front, so although there is a high confidence in showers on Wednesday, confidence is lower in the timing. Expecting post frontal precipitation in the northeast mountains, light, with a trace of snow possible in the highest elevations.
Showers and isolated thunder may reach interior se Ga by late afternoon ahead of approaching cold front. Patchy sea fog possible over the cooler near shore GA waters as dewpoints have reached and slightly exceeded water temperatures.
549 PM CST Tue Nov 29 2016 Early afternoon water vapor imagery together with GFS 500mb heights and surface obs show a broad upper level trough across the central Conus, with the center of an upper level low across central Minnesota. Over the next 36 hours this upper level low will slowly meander to the east southeast. we have the Wednesday night upper low to spread east taking the light snow.
After that a cold front will move through bringing cooler and quiet weather to the area through the end of the work week. This is not a clear cut scenario as lift will still be broad over our region through much of the evening until a strong s/w (currently moving over the TX panhandle) pushes towards the Lower MS Valley. Once this feature gets closer convection may become more widespread and robust along the cold front. If the h85 jet can strengthen enough over our CWA then storms would be able to fire near the I 10/12 corridor ahead of the cold front and increasing the risk for severe weather. our cold front will eventually stall over the central Gulf.
Surface analysis this evening places a warm front from northern Alabama into Northeast/Central Mississippi and Northern Louisiana. Warm front continues to lift north with lower 60s dewpoints beginning to push into northern MS. upper trough. This is spreading lift across the Lower Mississippi Valley. The associated cold front is pushing east into the Arklatex at this time. As the warm front lifts into North Mississippi and the cold front approaches from the west a surface wave develops over Western Mississippi early this evening and tracks NE across North Mississippi.
Front will approach late tonight ushering in cooler temperatures and clouds, and increasing rain chances from Rosebud county westward during the overnight hours. Upper flow becomes more southwesterly today with an area of low pressure at the surface lifting through the area. Winds will turn north northeast this evening and overnight as an initial cold front drops south through the region. Best precipitation chances will be over the higher terrain. Temperatures on Thursday will be a good 15 to 20 degrees cooler than Wednesday with the cold frontal passage.
707 AM EDT WED AUG 17 2016 Low pressure will cross the region early this morning and then exit across the Canadian Maritimes this afternoon. A cold front will cross the region Thursday.
However, uncertain how much the cap, albeit fairly weak, will erode this afternoon, especially given the low level WAA that guidance suggests. Byrd Dry weather to persist through Thursday night for the most part, then as ridge moves to our east, southerly flow to return once again. Will see increasing moisture and instability ahead of a strong cold front.
616 AM CDT WED AUG 17 2016 Outside of one small cluster of weakening thunderstorms over north central Nebraska, most of the convective activity early this morning was located east of the area in association with a more dominant mid level trough. Surface features are forecast to remain rather weak through Thursday and the upper flow transitions from northwest flow to more zonal as a strong upper trough moves out of western and central Canada towards the northern plains.
Upper level low over northern Nevada continues to spread moisture north into the forecast area for isolated showers and thunderstorms mainly south of the Snake River, across the Magic Valley and eastern section of the West Central and Boise Mountains.
Morning KXMR sounding shows slightly cooler conditions in the mid levels compared with the sounding from 24 hours prior with 700/500mb temps respectively at +8. There remains fairly deep layer ridging across north FL and the southeastern U. Deep ridging continues across north FL and the southeast U.
Models do show the cold front advancing to a point along the international border late afternoon. Templer Previous Discussion - An upper ridge over Montana will be flattened by an upper trough moving through the Canadian Prairies this morning. Then, a cold front will drop south across the forecast area late this afternoon and early evening. Air mass will become somewhat unstable ahead of the cold front allowing for the chance of thunderstorms. Upper trough over Western Canada along with a secondary cold front drops south into Montana during the day which will bring enough moisture with it for a chance of showers and thunderstorms. With the trough over Montana Thursday night, the southwest half of the forecast area will have deep moisture over it with showers possibly thunderstorms.
Stronger push of cooler air still on track for early Thursday with widespread showers and thunderstorms developing. A low pressure trof is approaching the area and the associated cold front has shifted surface flow to the north along the northern tier of the region.
A slowly southward moving boundary today will help little to eject the ample low-level moisture, and with daytime heating and the upper trough approaching, scattered showers and thunderstorms will develop again today. Have adjusted POPs across the north as forcing should remain broad across the region with the aforementioned trough and as indicated by latest HRRR run. Broad upper-level trough will begin to shift east over the forecast area tonight and Thursday.
Shower and thunderstorm activity will favor the higher terrain. A little better synoptic ascent is also forecast over northern Arizona in response to an upper level open wave trough over the southern CA/NV border.
A the same time, surface ridging remains across north FL and the southeastern U. Coastal trof that was over the adjacent waters overnight has moved inland this morning and extends from the GA coast with axis extending southward into central FL. Slightly drier air has advected into SE GA with the ridge nudging into the state with the overall atmospheric column not as moist as it is in NE FL. Onshore winds around 10 knots will prevail through Thursday with the ridge axis positioned just north of the region.
1001 AM EDT WED AUG 17 2016 Cold front will move through the forecast area today providing more rain and thunderstorms. Another cold front this weekend. Tracking mid to upper level trough moving through central and eastern KY this morning with associated band of showers and isolated thunderstorms. Latest satellite imagery indicate that cloud tops are starting to cool, as trough moving into an area of more favorable development. So, we could see more pronounced precipitation development as the trough moves across this afternoon, especially along the Ohio River counties. By Thursday morning the cold front should be mostly through the region.
1005 AM EDT WED AUG 17 2016 A weak area of high pressure will build in with drier conditions today. A an upper level trough may bring a brief showers to the north and mountains tonight and Thursday.
1219 PM EDT WED AUG 17 2016 Today will be drier and cooler behind a cold front with mainly dry conditions.
731 AM EDT WED AUG 17 2016 A weak area of high pressure will build in with drier conditions today. A an upper level trough may bring a brief showers to the north and mountains tonight and Thursday.
High pressure will bring hotter temperatures and fewer thunderstorms early this week. As high pressure shifts off to the east, deeper moisture will return along with an increasing chance of thunderstorms the second half of the week. Water vapor imagery continues to show a ridge of high pressure over the eastern Pacific waters with the axis extending southeast into the central Baja peninsula. Valid through 18/18Z High pressure with VFR conditions across the area.
735 AM EDT WED AUG 17 2016 GA will remain under the influence of the western Atlantic ridge and a moist tropical airmass. The two main atmospheric features are the moisture plume extending from eastern TX to the New England states and the Bermuda ridge that stays parked over the region through the end of the week. This ridge is beginning to weaken but it will continue to keep the main axis of moisture north and west of our area through Thu Night. This ridge eventually allows the deeper moisture to move into our area Fri Morning and will see increased chances of rain through the weekend.
1029 AM EDT WED AUG 17 2016 Upper-ridge of high pressure over central NC is still nosing its way into the eastern Tennessee Valley and Southern Appalachian region. The southwest flow around the western edge of the ridge has helped to advect very humid and moist air from the Gulf of Mexico into the area. Chattanooga Airport, TN 93 73 92 73 / 60 30 40 30 Knoxville McGhee Tyson Airport, TN 92 70 90 72 / 60 50 40 30 Oak Ridge, TN 92 70 90 72 / 60 40 40 30 Tri Cities Airport, TN 90 68 87 68 / 60 50 50 30.
1023 AM EDT WED AUG 17 2016 High pressure will remain centered well off the coast this afternoon.
743 AM EDT Wed Aug 17 2016 Low pressure will move east of the area this morning and this will help bring any lingering showers to an end.
Expect precipitation to taper off from west to east overnight as the trough axis crosses the region. Broad upper-level trough will begin to shift farther east over the forecast area Thursday. Models have been hinting at precipitation to occur over the southeast forecast area by Thursday afternoon across higher instability locations while the trough axis passes east and thus have added chance POPs.
1023 AM EDT Wed Aug 17 2016 Low pressure will move east of the area this morning and this will help bring any lingering showers to an end.
932 AM EDT WED AUG 17 2016 Skies are partly to mostly cloudy with temperatures ranging from the mid 70s in the Upper Keys to the lower to mid 80s elsewhere along the island chain. Surface wise, a Western Atlantic ridge extends across the Southeast United States and the northern portion of the Sunshine State. Closer to home, a subtle trough lies just offshore of the Southeast Florida coast southward to near the Cuban coast. Northeast to east winds will turn mostly east at similar speeds with the higher winds on Hawk channel and especially the Florida Straits.
957 AM EDT WED AUG 17 2016 Low pressure will cross the region early this morning and then exit across the Canadian Maritimes this afternoon. A cold front will cross the region Thursday.
1147 AM EDT WED AUG 17 2016 High pressure in the Atlantic will shift a little farther eastward and a weak pressure trough will develop in the forecast area today. The trough will become more pronounced Thursday. Upper level ridge continues to dominate over the region today with warm mid level temperatures around +10C at 700mb. 8 and confined in the lower layers of the atmosphere with drier air aloft. Overall coverage is not expected to be great due to suppression from the upper ridge and limited moisture but isolated to scattered convection is expected with moderate instability and will continue to carry 20/30 pops. Temperatures already pushing into the lower 90s late this morning with convective temperatures being met and resulting in cumulus development.
1028 AM EDT WED AUG 17 2016 A weak trof of low pressure will remain over the middle of the state for the next couple of days.
1259 AM EST Tue Feb 21 2017 High pressure will linger across the region through the rest of this week.
/issued 1035 PM CST Mon Feb 20 2017/ As the rain has ended the cooler air and wet grounds will allow the formation of fog overnight with some areas having visibility restrictions lower than one mile.