Aikyam-Lab/Synoptic-Bench huggingface dataset:
Models continue to agree wrt the progressive dry shrtwv trof pattern about every 24hrs. The next shrtwv trof will arrive late Tue PM, late enough for temps to climb back to the M60s across most of the PB and L70s Rio Grande. Low level thermal ridging and downslope winds on Wed ahead of next shrtwv trof will push temps up farther above normal. As shrtwv trof/assocd front pass Thur AM winds will have a chance to increase into the windy category (20-30 mph) between 15Z-21Z Thur as high temps fall back into the 55-60 range, except warmer Rio Grande. This is all ahead of what looks to be a stronger cold front next Mon with potential for some precip mainly n of I-20.
CONTINUES TO DEPICT LARGE SCALE TROUGHING ACROSS THE EASTERN HALF OF THE CONUS. AT THE SURFACE AND IN THE LOWER TO MIDDLE LEVELS. THE AFOREMENTIONED SURFACE RIDGING MOVES LITTLE. THIS INFLUX OF THIS EVEN COOLER AND MORE DENSE AIR DOWN THE SPINE OF THE FLORIDA PENINSULA WILL GENERATE THE WINDS BECAUSE BOTH THE SHALLOW AND DEEPER SURROUNDING WATERS REMAIN SO MUCH WARMER THAN THE AIR. WINDS AND SEAS WILL INCREASE AGAIN THIS EVENING GIVEN THE DRAINAGE OF EVEN COOLER AND DRIER AIR FROM OFF OF THE FLORIDA PENINSULA.
PATCHY FREEZING FOG WAS ADDED TO WESTERN AREAS LATER TONIGHT SINCE SURFACE MOISTURE CONTINUES TO INCREASE IN THESE AREAS.
BUT A STRONGER TROUGH WILL COME IN LATER TUESDAY WITH PCPN FOR ALL ZONES TUESDAY AFTERNOON AND NIGHT.
701 PM EST MON JAN 18 2016 LOW PRESSURE WILL CONSOLIDATE OVER EASTERN CANADA TONIGHT AND TUESDAY.
AS NORTHWEST BREEZES FILTERING COOLER AIR INTO THE REGION. SURFACE WINDS VEER SLIGHTLY INTO TOMORROW AFTERNOON AS HIGH PRESSURE NEARS THE EASTERN SEABOARD.
TEMPERATURES STILL REMAIN ON TRACK TO GET TO THE LOWEST READINGS SO FAR THIS WINTER. IF NOT A DEGREE OR TWO BELOW ZERO AS HIGH PRESSURE CONTINUES TO BUILD INTO THE OH VALLEY REGION. LESSENING GRADIENT TONIGHT AS WELL WITH THE CENTER OF THE HIGH MOVING THROUGH THE AREA WILL MEAN FOR LESS WIND. AS THE HIGH REMAINS OVER THE AREA THROUGH THE DAY ON TUESDAY. DESPITE SOUTHERLY FLOW DEVELOPING AHEAD OF THIS APPROACHING COLD FRONT. IN FACT TEMPS ACROSS THE RIDGES WILL BE IN THE TEENS FOR LOWS TUESDAY NIGHT WITH VALLEYS SEEING POSSIBLY SEEING AROUND 10.
AN UPPER LEVEL LOW WILL DRIFT WESTWARD ALONG THE GULF COAST TODAY AS UPPER LEVEL HIGH PRESSURE BUILDS OVER OUR REGION. A COLD FRONT WILL BRING A BETTER CHANCE OF MUCH NEEDED RAINFALL LATER IN THE WEEK. THIS LOW DECK OF CLOUDINESS IS FORECAST TO GRADUALLY BEGIN TO LIFT AND DISSIPATE BY MID TO LATE MORNING REVEALING PARTLY SUNNY SKIES. HIGH PRESSURE AT THE SURFACE AND ALOFT WILL SUPPLY STABILITY AND A RELATIVE SINKING AIR MASS TODAY RESULTING IN ONLY AROUND A 10 POP TODAY FOR CONVECTION.
THE BEST CHANCE FOR ANY SHOWERS AND THUNDERSTORMS WILL BE OVER THE MOUNTAINS CLOSER TO A STALLED COLD FRONT.
LATE SUMMER TIME WEATHER PATTERN SETTING UP OVER SOUTH FLORIDA A MID TO UPPER LEVEL LOW OVER THE NORTHEAST GULF OF MEXICO WILL MOVE SLOWLY WEST INTO THE NORTHERN CENTRAL GULF OF MEXICO TODAY. AS HIGH PRESSURE REMAINS OVER THE WESTERN ATLANTIC WATERS.
AN UPPER LOW OVER THE NORTHEAST GULF OF MEXICO WILL BROADEN AND GRADUALLY MOVE WEST ALONG THE COAST OVER THE NEXT SEVERAL DAYS. BEING ON THE PERIPHERY OF THIS UPPER LOW WILL NOT HELP US WITH OUR DRY CONDITIONS IN THE CWA. THE HIGHS WERE BUMPED UP A DEGREE OR TWO FROM GUIDANCE AS THE PAST TWO DAYS WE HAVE OVERACHIEVED.
DRY AND SLIGHTLY WARMER CONDITIONS EXPECTED FOR LABOR DAY WITH WEAK HIGH PRESSURE BUILDING ALOFT. A WARM FRONT PASSING ACROSS WASHINGTON MAY SPREAD SOME LIGHT RAIN ACROSS SW WASHINGTON EARLY TUESDAY MORNING.
THE SYNOPTIC PATTERN EARLY THIS MORNING FEATURES A BROAD RIDGE ACROSS MUCH OF THE EASTERN CONUS. WITH A VERY BROAD/WEAK LOW CONTINUING TO SPIN BENEATH THE RIDGE OVER NORTHERN GEORGIA. A SHEAR AXIS NOTED ON THE NORTHWEST SIDE OF THIS LOW WILL BE THE MAIN FOCUS TODAY. IT WAS ALL SPARKED WITHIN THE SHEAR AXIS BETWEEN THE UPPER LOW TO THE SOUTHEAST AND THE AMPLIFIED RIDGE ACROSS THE GREAT LAKES/MIDWEST REGION. AREAS MAINLY EAST OF I-65 WILL ONCE AGAIN BE WITHIN THIS SHEAR AXIS TODAY THROUGH WHICH VERY SUBTLE UPPER-LEVEL WAVES WILL TRAVERSE AS THEY ROTATE AROUND THE UPPER LOW. THE UPPER LOW WILL BECOME LESS OF A PLAYER AS IT MOVES OFF TO THE SOUTHWEST.
THE UPPER RIDGE THAT WAS IN PLACE YESTERDAY AND SQUASHED MOST SHOWER ACTIVITY IS BEGINNING TO SLIDE WEST AS AN UPPER LOW OVER THE SOUTHEASTERN CONUS MOVES WEST. THE EASTERN COUNTIES WILL ALSO FEEL LESS EFFECTS FROM THE UPPER RIDGE AND AFTERNOON HEATING SHOULD BE ABLE TO SPARK SOME SHOWER AND THUNDERSTORM ACTIVITY. HEAT INDEX VALUES WILL BE A DEGREE OR TWO WARMER THAN THE AMBIENT TEMPERATURE. THE UPPER RIDGE WILL BE FARTHER WEST/MUCH WEAKER AND THE UPPER LOW WILL BE A BIT CLOSER TO OUR REGION. THE HIGHER MOISTURE VALUES WILL ALSO SHIFT A BIT WEST AND THIS ALL SHOULD EQUATE TO SLIGHT CHANCES OF AFTERNOON SHOWERS AND STORMS FOR THE EASTERN HALF OF THE AREA.
208 AM EDT MON SEP 7 2015 A RIDGE OF HIGH PRESSURE WILL MAINTAIN ABNORMALLY WARM AND MAINLY DRY WEATHER FOR THE NEXT SEVERAL DAYS. THE PATTERN WILL START TO CHANGE IN THE MIDDLE OF THE WEEK AS THE UPPER LEVEL FLOW FLATTENS OUT AND A COLD FRONT DROPS DOWN FROM THE UPPER GREAT LAKES REGION.
605 AM EDT MON SEP 7 2015 HIGH PRESSURE FROM THE MID ATLANTIC COAST ACROSS THE LOWER LAKES WILL DRIFT SOUTHEAST AND MOVE OFF THE EAST COAST TUESDAY.
MID AND HIGH LEVEL CLOUDS ALREADY SPREADING IN FROM THE WEST THIS EVENING FROM THE SHORT WAVE TROUGH MOVING TOWARDS THE REGION. THIS TROUGH WILL INDUCE RETURN FLOW/LLJ LATER TONIGHT. COLD FRONT HAS CLEARED THE REGION. COOLER/MUCH DRIER AIR HAS PUSHED INTO THE WESTERN DAKOTAS WITH DEWPOINTS FALLING INTO THE 30S. HIGH PRESSURE MOVES OVERHEAD. WITH THE UPPER LOW TO THE NORTHWEST. SEVERAL WAVES WILL PIVOT AROUND THE BASE OF THE LOW AND AFFECT THE REGION. COOLER AND MOSTLY DRY.
as a strong ridge of high pressure aloft anchors across the Ohio Valley. The upper ridge retreats as energy in the northern stream dives southeast across the upper Midwest. and low pressure aloft drifts along the Gulf Coast. H5 Heights lower into the mid and upper 580s dm (from their weekend peaks in the low-mid 590s dm), and while temps will still be above normal, they'll at least fall off their weekend extremes.
FURTHER EAST THE TAIL END OF THE PLAINS COLD FRONT IS STALLED FROM ABOUT LAMAR TO AKRON WITH BETTER MOISTURE ON THE EAST SIDE. A COLD FRONT WILL BE APPROACHING FROM THE NORTH LATE. ALSO A BIT MORE WIND FOR THE HIGH MOUNTAINS THIS MORNING AND AGAIN LATER TONIGHT. MODELS HAVE A WEAK UPPER TROUGH TO MOVES ACROSS THE CWA TUESDAY EARLY.
Early morning water vapor loops show an elongated mid-upper level low and associated circulation, from near the Piedmont region of the Carolinas, to the north-central Gulf of Mexico. This low is projected to consolidate today in an area just offshore of Mobile, Alabama. Satellite derived PWAT products show deeper moisture situated just southeast of our area, and the east to southeast flow in the low-mid levels is expected to advect that air mass back to the northwest. One potentially negating factor would be some slight height rises or negative vorticity advection aloft as the mid-upper level low shifts from NE to SW across the area. Highs today should be in the upper 80s to around 90 degrees inland, and in the low-mid 80s along the immediate Gulf coastline.
630 AM EDT MON SEP 7 2015 SCATTERED SHWRS/ISOLATED TSTMS PREVAIL OFFSHORE ACROSS THE FL EAST COAST CLOSE TO AN INVERTED TROUGH. AND ACROSS THE NE GULF WATERS NEAR LOW PRESSURE. MID LEVEL LOW PRESSURE WILL GRADUALLY MOVE FROM THE NE GULF TODAY WESTWARD TO THE NORTH-CENTRAL GULF COAST BY LATE TONIGHT. RESULTING IN THE INVERTED TROUGH TO MOVE ONTO THE FL PENINSULA LATER TODAY. IMPULSES ROTATING AROUND THE LOW TO THE WEST WILL COMBINE WITH THE INVERTED TROUGH AND SEA BREEZE INTERACTION TO PRODUCE NUMEROUS SHWRS/TSTMS ACROSS MOST OF NE FL THIS AFTN. WITH LOWS TNGT IN THE LOWER/MID 70S. THE MID/UPPER LOW WILL CONTINUE TO RETROGRADE TO THE WEST. WITH UPPER LEVEL RIDGING BEGINNING TO BUILD IN FROM THE SOUTHEAST. HIGH PRESSURE RIDGE WILL SLIDE SOUTHEAST TUESDAY NIGHT. ALLOWING A TROUGH TO APPROACH FROM THE NORTHWEST.
503 AM EDT MON SEP 7 2015 A COLD FRONT WILL MOVE INTO THE AREA TODAY AND TONIGHT.
Highs cooler than yesterday, in the lower 90s over most of the area, looks reasonable given the potential cloud cover. Have 20% pops as far southeast as I-70 by Tue afternoon while areas southeast of I-70 stay dry and hot Tue with highs in the lower 90s. Cold front moves through southeast IL on Wed with as likely chances shift into southeast IL Wed. Cooler highs Wed in the lower 80s with some upper 70s far northern counties of Knox. GFS seems too fast with cold front and bringing in dry air which this model is dry in southeast IL by Wed evening. Preferred slower ECMWF model since front is pushing into a strong subtropical ridge over the southern states.
A WARMING TREND WILL PERSIST THROUGH LABOR DAY AND THEN ON THROUGH THE UPCOMING WORK WEEK AS HIGH PRESSURE BUILDS OVER THE STATE.
A 500MB RIDGE CENTERED OVER WEST TEXAS AND A 500MB LOW/TROUGH OVER THE NORTHERN GULF OF MEXICO. HIGH TEMPERATURES TODAY AND TUESDAY WILL RANGE FROM THE LOWER 90S NEAR THE COAST TO AROUND 100 ACROSS THE UPPER VALLEY.
THE AIRMASS CHANGE HAS OCCURRED WITH MUCH COOLER AND DRIER ADVECTING INTO THE REGION. UPPER LOW WILL SLOWLY PROPAGATE EAST ACROSS CANADA. AND SLIGHTLY COOLER AS THE UPPER LOW IN CANADA SHIFTS EAST.
430 AM EDT MON SEP 7 2015 A RIDGE OF HIGH PRESSURE WILL MAINTAIN ABNORMALLY WARM AND MAINLY DRY WEATHER FOR THE NEXT SEVERAL DAYS. THE PATTERN WILL START TO CHANGE IN THE MIDDLE OF THE WEEK AS THE UPPER LEVEL FLOW FLATTENS OUT AND A COLD FRONT DROPS DOWN FROM THE UPPER GREAT LAKES REGION.
140 AM EDT MON SEP 7 2015 HIGH PRESSURE ALONG THE EAST COAST WILL REMAIN NEARLY STATIONARY THROUGH MONDAY. SLOWING THE PROGRESS OF A COLD FRONT ACROSS THE GREAT LAKES AND MIDWEST. A WAVE OF LOW PRESSURE WILL TRACK NORTHEAST ACROSS THE CENTRAL GREAT LAKES TUESDAY NIGHT.
400 AM EDT MON SEP 7 2015 UPPER LEVEL RIDGE BREAKS DOWN TUESDAY. AS AN UPPER LEVEL TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WEST.
213 AM PDT MON SEP 7 2015 HIGH PRESSURE OVER THE DESERT SOUTHWEST WILL LEAD TO VERY WARM AND DRY CONDITIONS. A WEAK BAGGY TROUGH OVER THE NORTHWEST SHIFTS EASTWARD TODAY ALLOWING THE AREA OF HIGH PRESSURE OVER THE SOUTHWEST TO EXPAND NORTHWARD.
524 AM EDT MON SEP 7 2015 A RIDGE OF HIGH PRESSURE WILL MAINTAIN ABNORMALLY WARM AND MAINLY DRY WEATHER FOR THE NEXT SEVERAL DAYS. THE PATTERN WILL START TO CHANGE IN THE MIDDLE OF THE WEEK AS THE UPPER LEVEL FLOW FLATTENS OUT AND A COLD FRONT DROPS DOWN FROM THE UPPER GREAT LAKES REGION.
AND TUESDAY A COLD FRONT IS CURRENTLY MAKING ITS WAY THROUGH WISCONSIN EARLY THIS MORNING. TO THE LOWER 80S ACROSS EAST CENTRAL WISCONSIN. THE COLD FRONT ITSELF WILL STALL OUT OVER SOUTHERN WISCONSIN AND NORTHERN ILLINOIS THIS EVENING. BEFORE PUSHING BACK NORTH AS A WARM FRONT LATER TONIGHT AND INTO TUESDAY. ABUNDANT SHOWERS AND THUNDERSTORMS ON TUESDAY WILL KEEP HIGHS MUTED IN THE LOWER TO MIDDLE 70S.
WATER VAPOR IMAGERY DEPICTS AN UPPER LEVEL LOW CENTERED OVER GEORGIA. WITH DRY AIR ON THE WEST SIDE OF THE LOW CURRENTLY ACROSS THE MID STATE. 00Z GFS/ECMWF SLOWLY RETROGRADE THIS LOW TO THE SOUTHWEST OVER THE NEXT FEW DAYS WHILE MOISTURE ADVECTS WESTWARD AROUND THE NORTH SIDE OF THE LOW INTO MIDDLE TENNESSEE.
SHOWERS IN THE AFTERNOON ARE EXPECTED TO REMAIN ANCHORED NEAR THE HIGHER TERRAIN.
Plains through midweek with an upper trough being carved out over the eastern ConUS by week/s end. This will result in the upper ridge which has been plaguing the southern U.
NORTHWEST FLOW WILL KEEP WARMER 850MB TEMPERATURES SUPPRESSED TO THE SOUTH. DID BUMP HIGHS UP A COUPLE OF DEGREES TODAY AS MAV GUIDANCE WAS A LITTLE WARMER AND LOW DEWPOINTS SHOULD ALLOW TEMPERATURES TO WARM EFFICIENTLY.
HIGH PRESSURE RIDGE OVERHEAD WILL BEGIN A GRADUAL SHIFT TO THE WEST TODAY. TO THE LOWER 90S EAST.
417 AM MDT MON SEP 7 2015 PREDAWN WATER VAPOR IMAGERY SHOWED A UPPER LOW SITUATED OVER CENTRAL SASKATCHEWAN WITH A TROUGH AXIS THROUGH THE NORTHERN ROCKIES AND GREAT BASIN. UPPER RIDGE EXTENDED FROM NORTHERN MX TO THE MIDWEST. THE REGIONAL SURFACE ANALYSIS PLACED A COLD FRONT FROM LAKE SUPERIOR THROUGH CENTRAL IA AND KS THEN NORTH ALONG THE CO FRONT RANGE AND WEST THROUGH CENTRAL UT. A WEAK TROUGH WAS LOCATED NEAR THE LARAMIE RANGE. THERE IS GOOD AGREEMENT WITH THE 00Z SHORT RANGE MODEL GUIDANCE PROGGING THE UPPER TROUGH AXIS TO THE WEST TO TRANSLATE EAST DURING THE NEXT 24 HOURS. TUESDAY WILL BE 5 TO 10 DEGREES COOLER ACROSS THE PLAINS FOLLOWING THE FRONTAL PASSAGE.
A PERSISTENT UPPER LEVEL TROF WILL CONTINUE TO ENHANCE CHANCES FOR MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS OVER THE NEXT SEVERAL DAYS.
654 AM EDT MON SEP 7 2015 UPPER LEVEL RIDGE BREAKS DOWN TUESDAY. AS AN UPPER LEVEL TROUGH AND SURFACE COLD FRONT APPROACH FROM THE WEST.
356 AM CDT MON SEP 7 2015 (Today and Tonight) It will be another persistence forecast today, with the upper ridge parked over West Central Texas.
154 AM EDT MON SEP 7 2015 UPPER LEVEL RIDGE THROUGH THE HOLIDAY WEEKEND. SHOWERS INCREASE MID WEEK AHEAD OF A COLD FRONT.
WEAK 850 JET CORE SKIRTS THE FAR SE CWA DURING THE MORNING WITH 850 TROUGH PASSAGE EXPECTED IN THE AFTERNOON.
WITH UPPER RIDGING STILL ANCHORED OVER THE SRN PLAINS NE INTO THE MID MS VALLEY THIS MORNING. ALTHOUGH THE RIDGE ALOFT SHOULD BEGIN TO FLATTEN SLOWLY S OVER THE NEXT 24 HOURS AS UPPER TROUGHING SLOWLY TRAVERSES THE NRN ROCKIES/PLAINS. WITH THE RIDGE FLATTENING FURTHER TUESDAY. AND PRIMARILY CONFINED TO THE HIGHER PW AIR OF E TX AND THE SRN SECTIONS OF NCNTRL LA. THE TROUGHING OVER THE NRN ROCKIES/PLAINS REMAINS PROGGED TO AMPLIFY FARTHER S ACROSS THE CNTRL PLAINS/MID MS VALLEY TUESDAY NIGHT. WHICH SHOULD HELP TO DEEPEN COOLER AIR OVER THE PLAINS AND ALLOW A WEAK COOL FRONT TO DRIFT INTO NCNTRL OK/SRN MO TUESDAY NIGHT.
Some of the high resolution models were depicting scattered showers/storms redeveloping later this afternoon across northeast MO and west central IL along possible outflow boundaries left over from the early morning convection. Much of the high level convective cloud debris may thin out and dissipate later this morning into the afternoon with above normal temperatures expected again today along with high humidities leading to maximum afternoon heat indices in the mid to upper 90s.
341 AM PDT MON SEP 7 2015 HIGH PRESSURE ALOFT WILL BRING A WARMING TREND THIS WEEK.
138 AM EDT MON SEP 7 2015 AS THE HIGH PRESSURE THAT HAS DOMINATED OUR WEATHER SLIDES OFF SHORE, PERSISTENT SOUTHWEST FLOW WILL LEAD TO AN INCREASE IN HUMIDITY AND TEMPERATURES FOR LABOR DAY.
The Northern Rockies will remain under a weak trough today, with unsettled flow and leftover moisture keeping the chance for light rain showers present, mainly from along I-90 and points north. Some lingering snowfall may occur in the high terrain, particularly in Glacier Park, but impacts and amounts will remain low.
342 AM EDT MON SEP 7 2015 HIGH PRESSURE FROM THE MID ATLANTIC COAST ACROSS THE LOWER LAKES WILL DRIFT SOUTHEAST AND MOVE OFF THE EAST COAST TUESDAY.
LOW PRESSURE AT 500 MB NOTED ACROSS SASKATCHEWAN IS MOVING EAST. WHICH IS CAUSING THE RIDGE THAT HAS BEEN OVER THE EASTERN UNITED STATES TO FLATTEN. A COLD FRONT EXTENDED SOUTHWEST TO NORTHEAST ACROSS THE FORECAST AREA FROM KDDC-KGBD-KCNK. THE ASSOCIATED COLD FRONT WITH THAT 500 MB LOW WILL BRING MUCH COOLER AIR INTO THE REGION. AS A SECONDARY SURGE OF COOLER AIR /ASSOCIATED WITH THE UPPER LEVEL LOW/ MOVES INTO THE AREA AND CAUSES FRONTOGENESIS.
A trough is moving into the Pacific NW per Water Vapor imagery and GOES High Density winds as the seemingly permanent ridge remains over the Southern Plains. This trough will move across the Canadian Prairie Provinces/Northern tier of states. This will cause the ridge to retrograde to the Desert SW/Great Basin region.
339 AM CDT MON SEP 7 2015 THANKS TO HIGH PRESSURE POSITIONED OVER THE MID ATLANTIC. SOUTH OF THE HIGH. AN UPPER LOW WAS IN THE PROCESS OF FORMING OVER THE EASTERN GULF. AN UPPER RIDGE WAS ACROSS THE SOUTHERN PLAINS. WITH A WEAK UPPER LOW MEANDERING WESTWARD OVER THE FAR SE. THE LOW FORMING OVER THE NE GULF SHOULD DEEPEN SOMEWHAT OVER THE NEXT DAY OR SO. IT WILL HELP PRODUCE TROUGHING IN THE POLAR JET FOR MID AND LATTER WEEK. THIS WILL HELP BRING A COLD FRONT TOWARD THE TENNESSEE VALLEY. COOLER AIR NORTH OF FRONT SHOULD FILTER SOUTHWARD.
354 AM EDT MON SEP 7 2015 ALOFT - AN UPPER LOW CENTERED ALONG THE GA/FL STATE LINE SPRAWLED ACROSS FL AND MUCH OF THE GULF OF MEXICO. SURFACE - ATLANTIC HIGH PRESSURE RIDGED IN OVER THE MID-ATLANTIC STATES WHILE A WEAK TROUGH WAS IN THE EASTERN GULF OF MEXICO. THE UPPER LOW TAKES A SLOW WEST-SOUTHWEST TRACK ALONG THE GULF COAST AND ARRIVES SOUTH OF LA BY THE END OF THE PERIOD. ON TUE THE LOW OPENS BACK INTO A TROUGH AND SLIDES WEST AS THE MID-ATLANTIC RIDGE EXPANDS DOWN THE EASTERN SEABOARD TO FL. THE UPPER LOW WILL PROVIDE SOME COOLER TEMPERATURES ALOFT TODAY BUT THESE WARM SLIGHTLY TUE AS THE LOW PULLS AWAY. WITH THE DEEP MOISTURE AND COOLER TEMPS ALOFT SOME OF THE STORMS MAY BECOME ROBUST AND POSSIBLY PRODUCE SOME SMALL HAIL.
AN UPPER LOW CENTERED OVER THE FL PENINSULA MEANDERS WEST. WITH THE UPPER RIDGE OVER THE PLAINS BECOMING LESS OF A FACTOR. MOISTURE REMAINS IN PLACE ACROSS THE AREA THROUGH THE PERIOD AS THE UPPER LOW SLOWLY MOVES WESTWARD AND WEAKENS. THE LOW WILL OPEN UP AND BE ABSORBED INTO THE A LONGWAVE TROUGH DIGGING DOWN FROM THE NORTH. THIS TROUGH WILL SEND A COLD FRONT TOWARD THE AREA LATE IN THE WEEK. AN UPPER LOW CENTERED OVER THE FLORIDA PENINSULA WILL MEANDER SLOWLY WEST.
317 AM CDT MON SEP 7 2015 THE MID SOUTH WILL REMAIN POSITIONED BETWEEN UPPER LEVEL HIGH PRESSURE OVER THE SOUTHERN PLAINS AND AN UPPER LEVEL LOW PRESSURE SYSTEM OVER GEORGIA TODAY. THE UPPER LOW WILL MOVE SOUTHWESTWARD THROUGH TUESDAY AND SHOULD SPREAD ISOLATED SHOWERS AND THUNDERSTORMS INTO PORTIONS OF WEST TENNESSEE NEAR THE TENNESSEE RIVER AND NORTHEAST MISSISSIPPI BY TUESDAY AFTERNOON.
RIDGING ALOFT SHOULD BE WEAKER AS WELL SO COULD SEE MORE SCT SHRA/TSRA TOMORROW.
WITH BOTH THE GULF CYCLONE AND ATLANTIC ANTICYCLONE MIGRATING WESTWARD. THIS CONFIGURATION WILL SET UP A SOUTHERLY FLOW IN THE LOWER AND MIDDLE TROPOSPHERE. WE HAVE MAINTAINED THE HIGHER 12-HOUR RAIN CHANCE FOR TONIGHT.
300 AM PDT MON SEP 7 2015 WEAK ONSHORE FLOW AND A BUILDING RIDGE OF HIGH PRESSURE WILL BRING A WARMING TREND THIS WEEK. SLIGHT COOLING IS POSSIBLE BY LATE IN THE WEEK AND THE WEEKEND AS THE RIDGE OF HIGH PRESSURE WEAKENS. A WEAK TROF OVERHEAD NOW WILL GIVE WAY TO AN UPPER HIGH TUESDAY. THIS UPPER HIGH WILL STRENGTHEN EACH DAY WED AND THU.
A LOW PRESSURE SYSTEM WILL BE TRACKING WESTWARD ACROSS THE FLORIDA PANHANDLE REGION THROUGH THE PERIOD. SHORT TERM CONVECTIVE MODELS ALL SHOW CONVECTION DEVELOPING IN THE HIGHER TERRAIN THIS AFTERNOON.
WHILE DEWPOINTS HAD FALLEN INTO THE LOWER 50S IN THE WEST. AND THE HIGH RESOLUTION CAMS WERE INDICATING SOME THREAT OF SHOWERS THIS AFTERNOON AND EVEN TONIGHT. HIGHS ON TUESDAY WILL RANGE FROM THE LOWER TO MIDDLE 70S UNDER PARTLY TO MOSTLY SUNNY SKIES. A SLOW-MOVING UPPER TROF WILL BE LOCATED OVER MANITOBA AND NORTHWEST ONTARIO TUESDAY EVENING WITH THE NORTHLAND NEAR THE BASE OF THE TROF.
630 AM EDT MON SEP 7 2015 A COLD FRONT WILL MOVE INTO THE AREA TODAY AND TONIGHT.
Highs cooler than yesterday, in the lower 80s over most of the area, looks reasonable given the potential cloud cover. Have 20% pops as far southeast as I-70 by Tue afternoon while areas southeast of I-70 stay dry and hot Tue with highs in the lower 90s. Cold front moves through southeast IL on Wed with as likely chances shift into southeast IL Wed. Cooler highs Wed in the lower 80s with some upper 70s far northern counties of Knox. GFS seems too fast with cold front and bringing in dry air which this model is dry in southeast IL by Wed evening. Preferred slower ECMWF model since front is pushing into a strong subtropical ridge over the southern states.
A WEAK DISTURBANCE WITHIN THE WSW-ENE FLOW IN CONJUNCTION WITH THE LOW PRES CYCLOGENESIS WILL ALLOW FOR SCTD SHWRS AND POSSIBLY A FEW TSTMS TO DEVELOP OVER SRN MN INTO SWRN WI THIS EVE THROUGH THE OVERNIGHT HRS. BUT AS THE LOW TRAVERSES EWD ALONG THE FRONT. THE LOW PRESSURE SYSTEM ACROSS IOWA AND ASSOCIATED FRONT WILL BE SHIFTING EAST INTO SOUTHERN WISCONSIN.
435 AM CDT MON SEP 7 2015 THE RIDGE CONTINUES TO FLATTEN AND WILL BE ALL BUT GONE BY THE END OF THIS PERIOD. HIGH PRESSURE CONTINUES TO FLATTEN LEADING TO MORE OR LESS ZONAL FLOW ACROSS THE REGION AS TC LINDA PARALLELS THE MEXICAN COAST ON A NWRD TREK.
TODAY THROUGH TUESDAY NIGHT BROAD UPPER TROUGH WILL REMAIN IN PLACE ACROSS SOUTHERN CANADA WITH THE FA ON THE ACTIVE SOUTHERN PERIPHERY. COVERAGE OF THIS CONVECTION IS EXPECTED TO INCREASE ACROSS SCENTRAL SD THIS MORNING AS THE THETA-E RIDGING NEARS THE ANCHORED JET STREAK ACROSS ND. SLIGHTLY WARMER TEMPS TODAY. COOLER TEMPS EXPECTED AS WEAK CAA WILL LINGER INTO THE AFTERNOON.
400 AM EDT MON SEP 7 2015 HIGH PRESSURE OVER THE CENTRAL APPALACHIANS WILL DOMINATE TODAY AND TUESDAY.
This isentropic lift is forecast to continue through the morning hours and gradually move eastward as the low level jet veers. Later tonight isentropic lift will likely increase ahead of the main deepening trough. So the best chance for storms should be near the state line and then into portions of northeast KS as the low level jet veers. Lows fall into the lower to mid 60s as front comes through quickly and brings in drier continental air behind.
A WEAK RIDGE OF HIGH PRESSURE WILL BUILD BEHIND THE DISTURBANCE. STRONG HIGH PRESSURE ALOFT WILL PREVAIL THE LATTER HALF OF THE WEEK FOR ABOVE NORMAL TEMPERATURES. WEAK UPPER LEVEL RIDGING WILL BRING STABLE CONDITIONS THIS AFTERNOON. A WARM FRONT WILL CLIP WESTERN WA ON TUE WHILE IT MOVES INTO SOUTHERN BRITISH COLUMBIA. THE WARMER AIR MASS WILL HELP BOOST TEMPS A BIT WITH DAYTIME HIGHS CLOSE TO NORMAL.
238 AM EDT MON SEP 7 2015 SCATTERED SHWRS/ISOLATED TSTMS PREVAIL OFFSHORE ACROSS THE FL EAST COAST CLOSE TO AN INVERTED TROUGH. AND ACROSS THE NE GULF WATERS NEAR LOW PRESSURE. MID LEVEL LOW PRESSURE WILL GRADUALLY MOVE FROM THE NE GULF TODAY WESTWARD TO THE NORTH-CENTRAL GULF COAST BY LATE TONIGHT. RESULTING IN THE INVERTED TROUGH TO MOVE ONTO THE FL PENINSULA LATER TODAY. IMPULSES ROTATING AROUND THE LOW TO THE WEST WILL COMBINE WITH THE INVERTED TROUGH AND SEA BREEZE INTERACTION TO PRODUCE NUMEROUS SHWRS/TSTMS ACROSS MOST OF NE FL THIS AFTN. WITH LOWS TNGT IN THE LOWER/MID 70S. THE MID/UPPER LOW WILL CONTINUE TO RETROGRADE TO THE WEST. WITH UPPER LEVEL RIDGING BEGINNING TO BUILD IN FROM THE SOUTHEAST. HIGH PRESSURE RIDGE WILL SLIDE SOUTHEAST TUESDAY NIGHT. ALLOWING A TROUGH TO APPROACH FROM THE NORTHWEST.
250 AM CDT MON SEP 7 2015 COLD FRONT AND ASSOCIATED CONVECTION TRAVERSING THE REGION AT THE MOMENT. TEMPERATURES WILL BE A BIT COOLER THAN THE PAST SEVERAL DAYS. THE CLOSED CIRCULATION AND LONG WAVE TROUGH SHIFTS EAST THROUGH SOUTHERN CANADA BY MID WEEK.
UPPER AIR ANALYSIS THIS MORNING SHOWED A RIDGE EXTENDING FROM MEXICO TO THE GREAT LAKES. THERE WAS A LOW OVER THE SOUTHEASTERN STATES AND A TROUGH ACROSS THE WEST FROM THE NORTHERN ROCKIES TO SOUTHERN CALIFORNIA. HIGH PRESSURE WAS CENTERED OVER EAST TEXAS AND WINDS WERE FROM THE SOUTH. THIS WILL WEAKEN THE RIDGE OVER TEXAS AND BRING SLIGHT CHANCE POPS TO OUR EASTERN COUNTIES DURING THE DAY MONDAY.
Ahead of this feature, a front over southern Kansas will move back north as a warm front into northern Kansas.
303 AM PDT MON SEP 7 2015 MOSTLY CLEAR SKIES AND INCREASING TEMPERATURES ARE EXPECTED FOR THE NEXT SEVERAL DAYS AS HIGH PRESSURE MOVES IN OVER THE REGION. A WARMING TREND AND CLEAR SKIES WILL DOMINATE THE REGION FOR SEVERAL DAYS AS A RIDGE OF HIGH PRESSURE MOVES OVER THE WEST COAST.