Aikyam-Lab/Synoptic-Bench huggingface dataset:
347 AM CST MON NOV 30 2015 (Today and Tonight) By this afternoon the upper low that has dominated the western CONUS for most of last week will be centered over the Central Plains and will continue to move to the northeast through tonight.
HAVE REMOVED MENTION OF PATCHY FREEZING DRIZZLE WITH ONLY A SLIGHT CHANCE TO LOW CHANCE POP FOR LIGHT SNOW. LARGE UPPER LEVEL LOW PRESSURE SYSTEM REMAINS ANCHORED ACROSS THE CENTRAL ROCKIES THIS AFTERNOON. WILL DUMBBELL EAST THEN NORTHEAST AROUND THE UPPER LEVEL LOW TONIGHT INTO MONDAY. THE UTAH DISTURBANCE WILL BECOME THE MAIN UPPER LEVEL LOW MONDAY. AS THE ORIGINAL UPPER LEVEL LOW FILLS AND WEAKENS ACROSS THE ROCKIES. CANNOT RULE OUT SOME PATCHY FREEZING DRIZZLE. WITH LITTLE TO EXPEDITE THE CYCLONE OUT OF THE AREA.
/ISSUED 919 PM CST SUN NOV 29 2015/ Upper level low remains to our northwest this evening with persistent moist airmass remaining in place. Any additional amounts should be on the light side as we finally wind down this rain event during the day Monday with the departure of upper low.
Rain potential will again spread into parts of northeast Oklahoma and northwest Arkansas later this morning, as well as far southeast Oklahoma, the former due to a disturbance positioned over southwest Kansas and into the Oklahoma and Texas Panhandle region and the latter in response to a strong upper level speed maximum in the base of the main upper low. The big question for this morning's forecast is how quickly the low cloudiness will erode.
THE WIND WILL BECOME NORTHERLY AND INCREASE BETWEEN 7 AND 12 KNOTS OVERNIGHT MONDAY WITH THE PASSAGE OF A WEAK COLD FRONT.
ALOFT THE GEM/GFS/ECMWF ARE QUITE SIMILAR MOVING NEUTRAL TILT TROF EAST ACROSS THE REGION. A HEAD OF THE SNOW THERE MAY BE A PERIOD OF LIGHT FREEZING DRIZZLE.
HIGH PRESSURE ON THE SFC IS WEAKENING AND WINDS WILL BECOME MORE VARIABLE. UPPER-LEVEL TROUGH TO THE WEST TO LINGER THROUGH MIDWEEK LEAVING THE REGION WITHIN SOUTHWEST FLOW.
TEMPERATURES WILL WARM TO ABOVE NORMAL BY MID-WEEK AS HIGH PRESSURE BUILDS ALOFT AND OFFSHORE FLOW CONTINUES. A TROUGH OF LOW PRESSURE WILL BRING COOLING AND A CHANCE OF RAIN LATE IN THE WEEK. WARM AND DRY WEATHER WILL LIKELY RETURN FOR THE WEEKEND AS A RIDGE OF HIGH PRESSURE MOVES INTO PLACE AND OFFSHORE FLOW REDEVELOPS. FORECAST MODELS CONTINUE TO SHOW UPPER LEVEL RIDGE OF HIGH PRESSURE GRADUALLY BUILDING OVER THE REGION.
THE MARGINALLY COLD TEMPERATURES DID SUPPORT A BRIEF WINDOW OF FREEZING RAIN. AND ANALYSIS SHOWS AT LEAST SOME BRANCH OF THE MOIST PLUME VEERED INTO THE OHIO VALLEY WILL INTERACT WITH THE UPPER LOW AS IS MOVES UP OVER IOWA AND MINNESOTA. THIS AGAIN WILL SET THE STAGE FOR A MARGINAL ENVIRONMENT FOR ANY FREEZING RAINFALL. WITH ASCENT INCREASING AHEAD OF THE APPROACHING UPPER LOW. THE NORTHWEST WILL SEE THE BEST POTENTIAL FOR SPOTTY FREEZING RAIN MIXED IN WITH THE LIGHT RAIN. ENDING ANY LOCALIZED FREEZING RAIN THREAT NORTHWEST BEFORE DAWN.
NAM AND GFS FCST SOUNDINGS BOTH SUPPORT MVFR CIGS IN THE AFTN OVER INLAND TAF SITES AS AN UPPER LOW OVER THE NORTHERN ROCKIES SHIFTS EAST.
AREAS OF FREEZING FOG WILL PERSIST ACROSS PORTIONS OF THE LOWER COLUMBIA BASIN AND THE FORECAST WAS UPDATED TO REFLECT THIS ALONG WITH ADDING SOME OCCASIONAL LIGHT SNOW. OTHERWISE HIGH PRESSURE REMAINS ENTRENCHED ACROSS THE REGION WITH DRY CONDITIONS CONTINUING. TEMPERATURES REMAIN IN THE BALL PARK AND THE PATCHY FREEZING FOG WILL PERSIST ACROSS THE ENTIRE COLUMBIA BASIN INTO MONDAY MORNING. POCKETS OF LIGHT SNOW HAVE DEVELOPED WITHIN THE LOW STRATUS CLOUD DECK MAINLY INVOF KYKM AND KPSC AND COULD CAUSE TEMPORARY REDUCTIONS IS VISIBILITY AND SLICK RUNWAYS HERE. HIGHER CIRRUS CLOUDS WILL SPREAD ACROSS THE REGION MAINLY AFTER 18-21Z ON MONDAY WITH LITTLE CHANGE TO LOW CLOUDS AND CIGS IN THE LOWER BASINS.
THE UPPER LOW THATS BEEN OVER THE GREAT BASIN FOR THE PAST WEEK IS SITTING OVER CENTRAL WYOMING TONIGHT.
Rainfall amounts will be up to a third of an inch, with the highest amounts over northeast Missouri and west central Illinois. Lows will be in the low 30s to low 40s.
328 AM CST MON NOV 30 2015 A strong upper low centered over WY this morning will wobble east across the Central Plains today.
Any insolation with temperatures warming to the lower 30s will allow some ice melt to occur, which will cause a temporary falling ice hazard around the area from midday through the afternoon hours. Clear sky is forecast tonight with a downslope west wind around 10 to 15 mph, leading to overnight lows from the mid teens at around Syracuse to the lower 20s around Medicine Lodge. The mid to late week weather across western Kansas will be welcomely tranquil as large scale ridging builds across the Rockies.
HIGH PRESSURE CONTINUES TO DOMINATE THE AREA. HIGH PRESSURE ALOFT WILL GENERALLY KEEP THE AIRMASS DRY WITH CLEAR SKIES.
1135 PM EST SUN NOV 29 2015 HIGH PRESSURE OVER EASTERN CANADA WILL DROP SOUTHEAST TO NEW ENGLAND ON MONDAY AS LOW PRESSURE DEVELOPS IN THE CENTRAL PLAINS.
Weak, low amplitude ridging continues aloft across the Tri-State region ahead of a large cutoff low over the Northern and Central Plains. At the surface, high pressure prevails locally as well, with a quasi-stationary front draped through the Tennessee and Lower Mississippi Valleys.
A COLD FRONT HAS STALLED ACROSS NORTH MISSISSIPPI EXTENDING INTO MIDDLE TENNESSEE AND DOES NOT LOOK LIKE IT IS GOING ANYWHERE ANY TIME SOON. BUT AS THE LARGER LONGWAVE TROUGH APPROACHES RAIN WILL LIKELY RETURN TO THE AREA EARLY TOMORROW.
1254 AM EST MON NOV 30 2015 HIGH PRESSURE CENTERED NORTH OF THE GREAT LAKES WILL BRING CONTINUED DRYING ACROSS THE OHIO VALLEY TONIGHT.
224 AM EST MON NOV 30 2015 STATIONARY FRONT RETURNS AS A WARM FRONT LATER TODAY AND TONIGHT.
APPRECIABLE RAIN HAS FINALLY ARRIVED IN THE NORTHWEST COUNTIES IN ASSOCIATION WITH A COLD FRONT. TEMPERATURES TOMORROW SHOULD ONCE AGAIN RISE WELL INTO THE 70S SOUTH OF THE LOW CLOUD DECK.
THE LARGE UPPER LEVEL LOW THAT HAD BEEN STALLED TO OUR NORTHWEST IS FINALLY MOVING EAST ACROSS THE ROCKIES THIS MORNING.
106 AM EST MON NOV 30 2015 HIGH PRESSURE WILL GIVE WAY TO A WEAK BACKDOOR COLD FRONT THAT APPROACHES THE AREA LATE TONIGHT AND EARLY MONDAY.
1208 AM EST MON NOV 30 2015 COOLER AIR IS SLIDING IN FROM THE NORTHEAST AS HIGH PRESSURE BUILDS INTO THE REGION TONIGHT. AN UPPER LOW OVER THE PLAINS STATES WILL SLIDE ACROSS THE GREAT LAKES THROUGH MIDWEEK.
SOUTHWEST FLOW WILL CONTINUE TONIGHT AHEAD OF AN UPPER LOW THAT WILL MOVE INTO SOUTHWEST NEBRASKA MONDAY. THE NAM, GFS AND ECMWF ARE SHOWING THE VORT CURRENTLY OVER WESTERN UTAH SWINGING AROUND THE BASE OF THE TROUGH AND INTO WESTERN KANSAS TONIGHT. THE NAM HAS THE LOWEST QPF ASSOCIATED WITH THIS VORT WHILE THE GFS HAS THE HIGHEST. THERE WILL ONLY BE A CHANCE OF SNOW EARLY THIS EVENING WITH SOME LIGHT FREEZING DRIZZLE POSSIBLE DUE TO THE LACK OF SUPPORTIVE MIDLEVEL MOISTURE. MAX TEMPERATURES SHOULD RISE TO THE LOWER 30S MONDAY.
THIS EVENING THROUGH MONDAY NIGHT ROCKIES UPPER LOW WILL SHIFT EAST WITH AN ASSOCIATED STRONG SOUTHERN PERIPHERY IMPULSE/JET STREAK. ATTENTION TURNS TOWARD THE EJECTING ROCKIES UPPER TROUGH/JET STREAK WHICH WILL REFLECT LL PRESSURE FALLS AND AN EVENTUAL FGEN/DEFORMATION RESPONSE INTO THE FA MONDAY MORNING. BUFFER PROGS INDICATE THE POTENTIAL FOR SOME FREEZING DRIZZLE LATE TONIGHT OVER FAR EASTERN SCENTRAL SD GIVEN NEUTRAL TEMPS PROFILES AROUND -5C. SIDED ON THE LOWER SIDE OF SNOW TOTALS.
TEMPERATURES REMAIN RIGHT AROUND FREEZING EARLY THIS MORNING WITH RADAR SHOWING AN AREA OF PRECIP MOVING OUT OF NORTHEAST KANSAS INTO SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. WITH TEMPERATURES EXPECTED TO REMAIN RIGHT AROUND FREEZING TODAY ANY SIGNIFICANT SNOW FOR EASTERN AREAS INCLUDING OMAHA WILL LIKELY DEPEND ON DEVELOPMENT OF DYNAMIC COOLING AND STRENGTH OF JET MAX CURRENTLY OVER NORTHEAST KANSAS AS IT TRACKS TO THE NORTHEAST THIS MORNING.
A weak warm front will try to move through the region Monday, but it will not be significant enough to even generate a few breaks in the low overcast. The warm frontal passage is associated with a rather intense storm system lifting northeast through the northern Plains/upper Midwest. The models hint at shower development over southeast Missouri and southern Illinois mainly on the trailing cold front Monday night, so will keep at least a chance PoP throughout the region, but likely to categorical PoPs will been posted in the southeast.
WATER VAPOR SHOWS ELONGATED UPPER LEVEL LOW EXTENDING FROM THE WESTERN DAKTOAS THROUGH THE DESERT SOUTHWEST. SOUTHERN PORTION OF THE UPPER LEVEL LOW IS EXPECTED TO PIVOT INTO THE PLAINS. AT THE SURFACE AHEAD OF THE LOW. SHORT TERM HIGH RES MODELS HAVE SUGGESTED THE POTENTIAL FOR FREEZING DRIZZLE DEVELOPING AHEAD OF THE MAIN UPPER LOW. STRONG POSITIVE VORTICITY ADVECTION IS EXPECTED THROUGHOUT THE DAY AS SHORT WAVES ROTATE AROUND THE UPPER LOW. THE UPPER WAVE PIVOTS THROUGH THE FORECAST AREA THROUGH THE EVENING HOURS WITH THE UPPER LOW CAMPED ACROSS THE FORECAST AREA THROUGH THE OVERNIGHT. AS THE LOW SLOWLY WORKS EAST.
ANOTHER LOW PRESSURE SYSTEM ALONG THE LEE OF THE ROCKIES IS INTENSIFYING WITH A FRONT DEVELOPING. IT WILL GET SWEPT UP IN THE UPPER FLOW AS AN UPPER LOW CIRCLES FROM THE UPPER ROCKIES INTO THE UPPER PLAINS.
325 AM CST MON NOV 30 2015 AT H5 LARGE CLOSED LOW OVER WYOMING AS SEEN IN WATER VAPOR. HIGH PRESSURE TO THE NORTHWEST OF THIS LOW OVER WASHINGTON IDAHO WITH RIDGE INTO WESTERN CANADA. TROUGH FROM HUDSON BAY LOW INTO THE NORTHEAST CONUS. HIGH PRESSURE OVER THE GULF AND PUERTO RICO. AT THE SURFACE A COLD FRONTAL BOUNDARY FROM LOUISIANA INTO THE CAROLINAS. LOW PRESSURE OVER THE COLORADO ROCKIES INTO NORTHERN NEW MEXICO.
345 AM CST MON NOV 30 2015 THE STORM SYSTEM THAT HELPED CREATE ALL THE ICY EXCITEMENT OVER THE HOLIDAY WEEKEND WAS NOW SPINNING SLOWLY EASTWARD THROUGH THE CENTRAL AND NORTHERN ROCKIES AND INTO THE HIGH PLAINS. THE CENTER OF THE LARGE UPPER LOW IS PROGGED TO SWING ACROSS NEBRASKA TODAY AND THEN ON TOWARD THE UPPER MIDWEST TONIGHT WHERE IT WILL DROP A HEFTY SWATH OF SNOW. SOUTH OF THE LOW. THE LIGHT WINDS AND RESIDUAL LOW-LEVEL MOISTURE TRAPPED WITHIN THE RIDGE COULD LEAD TO ANOTHER ROUND OF LOW CLOUDS AND FOG OFF THE CAPROCK.
The upper level trough with a closed low currently centered over Wyoming will push into Nebraska today. This will force a cold front through the area and allow rain to overspread the area yet again today. Temperatures this morning are ranging from just above freezing near the MO/IA border and are otherwise in the mid to upper 30s. However, model soundings suggest that there may not be ice crystals in the snow growth zone when temperatures drop below freezing.
408 AM EST MON NOV 30 2015 MOSTLY CLOUDY CONDITIONS CAN BE EXPECTED TODAY AS AN UPPER LEVEL DISTURBANCE AND LOW PRESSURE AREA APPROACH THE REGION.
WILL KEEP MAIN P-TYPE AS SNOW BUT WILL KEEP IN MENTION OF FREEZING DRIZZLE THRU 06Z MON. SOUTHWEST FLOW WILL CONTINUE TONIGHT AHEAD OF AN UPPER LOW THAT WILL MOVE INTO SOUTHWEST NEBRASKA MONDAY. THE NAM, GFS AND ECMWF ARE SHOWING THE VORT CURRENTLY OVER WESTERN UTAH SWINGING AROUND THE BASE OF THE TROUGH AND INTO WESTERN KANSAS TONIGHT. THE NAM HAS THE LOWEST QPF ASSOCIATED WITH THIS VORT WHILE THE GFS HAS THE HIGHEST. THERE WILL ONLY BE A CHANCE OF SNOW EARLY THIS EVENING WITH SOME LIGHT FREEZING DRIZZLE POSSIBLE DUE TO THE LACK OF SUPPORTIVE MIDLEVEL MOISTURE. MAX TEMPERATURES SHOULD RISE TO THE LOWER 30S MONDAY.
UPPER LOW CURRENTLY OVER SOUTH CENTRAL WYOMING WITH A WEATHER DISTURBANCE LIFTING NORTHEAST ACROSS THE AREA. PRECIPITATION CHANCES WILL DECREASE FROM SOUTHWEST TO NORTHEAST THROUGH THE DAY AS THE LOW REORGANIZES OVER CENTRAL NEBRASKA AND DRIER AIR ALOFT MOVES IN.
VIGOROUS UPPER LEVEL TROUGH ANCHORED ACROSS THE INTER-MOUNTAIN WEST CONTINUES TO EJECT WEAK PERTURBATIONS OUT OUR WAY IN WEST SOUTHWEST FLOW ALOFT. THE 850MB TROUGH AXIS WHICH HAS BEEN LOCKED WELL WEST OF OUR AREA ACROSS THE OK/TX PNHDL REGION. THE UPPER TROUGH ACROSS THE INTER-MOUNTAIN WEST WILL FINALLY BEGIN TO EJECT OUT INTO THE GREAT LAKES REGION ON TUE AS A STRONGER PIECE OF ENERGY DIGS INTO THE FOUR CORNERS REGION ALONG THE TROUGHS SOUTHWEST FLANK. THE STALLED 850MB TROUGH AXIS ACROSS OUR SOUTHERN ZONES WILL BEGIN TO SLOWLY LIFT BACK NORTH.
BUT LIGHT SNOW WAS REPORTED IN MOBRIDGE SO WE SPREAD A CHANCE OF LIGHT SNOW ALL THE WAY NORTH INTO THE BISMARCK/MANDAN AREA THROUGH 08 UTC. LOWS WERE ALSO ADJUSTED USING A TIME-LAGGED ENSEMBLE OF HRRR RUNS AS THAT GUIDANCE IS CAPTURING THE QUICK TEMPERATURE DROP WITH CLEAR SKIES IN NORTHWEST ND AS WELL AS THE RELATIVELY WARMER LOWS WHICH ARE EXPECTED IN SOUTH CENTRAL ND WHERE DEWPOINTS ARE HIGHER THIS EVENING AND CLOUD COVER WILL REDUCE RADIATIONAL COOLING.
THE UPPER TROUGH THAT HAS BEEN RESPONSIBLE FOR THE WIDESPREAD PRECIPITATION THE PAST SEVERAL DAYS WILL FINALLY EJECT NORTHEAST ACROSS THE REGION TODAY.
CALLS TO LOCAL OFFICIALS INDICATE THAT ANY DRIZZLE FALLING WITH TEMPERATURES IN THE LOWER 30S IS NOT CAUSING ANY ROAD ISSUES. BUT IF ANY DENSE FOG FORMS IT SHOULD BE IN AN ABOVE FREEZING ATMOSPHERE. FREEZING FOG ADVISORY REMAINS IN EFFECT FOR THE WESTERN TWO-THIRDS OF THE COMBINED PANHANDLE REGION THRU 9 AM. LIGHT WINTRY PRECIPITATION WILL DEVELOP ACROSS THE REGION WITH SNOW FAVORING THE NORTHERN PANHANDLE COUNTIES AND WINTRY MIX TO FREEZING DRIZZLE IN THE CENTRAL AND EASTERN PANHANDLE COUNTIES. LIFR TO IFR CIG WILL CONTINUE THRU 30/12Z AS LOW STRATUS AND FREEZING FOG REMAINS OVER THE TAF SITES.
While the deepest moisture will remain well to the southeast along an old frontal boundary across the Tennessee River Valley and further northwest in closer proximity to the approaching upper low, high chance to likely PoPs are warranted across the board this afternoon. Due to overcast conditions, light rain, and a continued easterly low- level flow, have undercut MAV guidance numbers, with high temperatures mainly in the lower to middle 40s.
1112 PM CST SUN NOV 29 2015 Wet, dank weather continues as sfc waves of low pressure and upper level disturbances continue to bring periods of light rain/drizzle northeastward. An upper low over the eastern Rockies will shift into the Midwest (IA/MN border) by Tue 12z/6am. This will push a front through our area Mon night finally kicking the low clouds/precip off to the east. Colder air wrapping around the low will keep high temperatures in the 40s with some low 50s along the MO/AR line Tue afternoon. There is decent agreement on another upper level low moving into the central/southern Rockies by Sat.
STRONG UPPER LEVEL LOW OVER THE MOUNTAIN WEST WILL CONTINUE TO SEND DISTURBANCES IN THE SOUTHERN STREAM ACROSS THE REGION. HIGH PRESSURE BUILDING DOWN FROM THE EASTERN ROCKIES AND UPPER LEVEL LOW FINALLY BEGINNING TO KICK OFF TO THE EAST.
107 AM EST MON NOV 30 2015 MOSTLY CLOUDY CONDITIONS CAN BE EXPECTED OVERNIGHT AS AN UPPER LEVEL DISTURBANCE AND LOW PRESSURE AREA APPROACH THE REGION.
1025 PM MST SUN NOV 29 2015 THE ELONGATING AREA OF LOW PRESSURE CONTINUES TO GENERATE LIGHT SNOWFALL THIS AFTERNOON. THE CORE OF THE LOW PRESSURE WILL SHIFT EAST OF THE FORECAST AREA MONDAY AFTERNOON. STRONGER NORTHWEST FLOW WILL MOVE IN BEHIND THE LOW. THE QUESTION WILL BE CAN THE WINDS MIX DOWN AND BLOW OUT THE WEAKENED INVERSIONS IN THE VALLEYS AND BASINS? THE HIGHER RESOLUTION MODELS DO SHOW THE NORTHWEST WINDS INTRUDE FROM NORTHWEST TO SOUTHEAST ACROSS THE WIND RIVER AND UPPER GREEN RIVER BASINS AS WELL AS ACROSS THE WESTERN BIGHORN BASIN.
THE COLD FRONT IS CURRENTLY SOUTH OF THE FORECAST AREA OVER CENTRAL MISSISSIPPI WITH SHOWERS MOVING ACROSS NORTH MISSISSIPPI AND EXTREME SOUTHERN SECTIONS OF WEST TENNESSEE. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS TODAY FROM THE LOWER 50S TO LOWER 60S.
TEMPERATURES HAVE FALLEN TO 32 F ACROSS BUCHANAN/DELAWARE/AND DUBUQUE COUNTIES BUT ROAD SFC TEMPERATURES ARE A DEGREE OR TWO WARMER THEREBY PRECLUDING MUCH OF A THREAT FOR ICING. ALL PRECIPITATION THAT FALLS TODAY WILL FALL AS PLAIN RAIN AS TEMPS REMAIN ABOVE FREEZING. COLD FRONT FORECAST TO PUSH THROUGH E IOWA/W ILLINOIS BETWEEN 2-4 AM CST. LOWS WILL BE IN THE LOWER 30S WEST AND CENTRAL.
FREEZING FOG ADVISORY REMAINS IN EFFECT FOR THE WESTERN TWO-THIRDS OF THE COMBINED PANHANDLE REGION THRU 9 AM. LIGHT WINTRY PRECIPITATION WILL DEVELOP ACROSS THE REGION WITH SNOW FAVORING THE NORTHERN PANHANDLE COUNTIES AND WINTRY MIX TO FREEZING DRIZZLE IN THE CENTRAL AND EASTERN PANHANDLE COUNTIES. LIFR TO IFR CIG WILL CONTINUE THRU 30/12Z AS LOW STRATUS AND FREEZING FOG REMAINS OVER THE TAF SITES. FREEZING FOG ADVISORY UNTIL 9 AM CST MONDAY FOR THE FOLLOWING ZONES: ARMSTRONG. FREEZING FOG ADVISORY UNTIL 9 AM CST MONDAY FOR THE FOLLOWING ZONES: CIMARRON.
1257 AM EST MON NOV 30 2015 COOLER AIR IS SLIDING IN FROM THE NORTHEAST AS HIGH PRESSURE BUILDS INTO THE REGION TONIGHT. AN UPPER LOW OVER THE PLAINS STATES WILL SLIDE ACROSS THE GREAT LAKES THROUGH MIDWEEK.
Temperatures should remain above freezing so no freezing fog is expected. /issued 200 PM CST SUN NOV 29 2015/ Area radars show rainfall has finally cleared the lwr Trans Pecos, whereas WV imagery shows drier air intruding into West Texas and Southeast New Mexico as the upper trough begins migrating to the upper Midwest. At the sfc, winds have gone light/variable, and temps have climbed abv freezing everywhere.
RIDGE NORTH OF THE KEYS AREA. A TROUGH ACROSS THE TENNESSEE AND OHIO RIVER VALLEYS. THE ADDITION OF AN UPPER LOW DRIFTING ACROSS THE SOUTHEASTERN BAHAMAS IS ENHANCING THE NORTHEASTERLY FLOW AROUND THE RIDGE NORTH OF THE KEYS. THIS LOW IS ALSO THE CULPRIT FOR THE CONVERGENCE ZONE ACROSS THE KEYS AREA AT THIS HOUR.
AND IN THE LOWER TO MID 60S NEAR THE IMMEDIATE COAST.
339 AM EST MON NOV 30 2015 STATIONARY FRONT RETURNS AS A WARM FRONT LATER TODAY AND TONIGHT.
A COLD UPPER LOW WILL CONTINUE TO SLOWLY MOVE OUT OF THE AREA TONIGHT. HIGH PRESSURE WILL GRADUALLY BUILD OVER THE REGION THROUGH MID WEEK. THE UPPER LOW HAS RE-CENTERED ITSELF OVER CENTRAL WYOMING. VORT LOBES ROTATING AROUND THE LOW COULD ALSO INCREASE THE CHANCE OF PRECIPITATION.
A LARGE UPPER LOW CURRENTLY OVER THE WESTERN CONUS WILL SLOWLY MOVE EAST. AND IT WILL ALSO SPIRAL A COLD FRONT EASTWARD INTO KY MONDAY NIGHT. WITH ALL OF THE FORECAST AREA EXPECTING SHOWERS AHEAD OF THE COLD FRONT ON MONDAY NIGHT.
WE WILL BE ON THE FAR NORTHWESTERN PERIPHERY OF THE RELATIVELY DEEPER MOISTURE WRAPPING AROUND THE UPPER LEVEL LOW OVER THE NW CARIBBEAN TODAY. WITH LIGHTER WINDS, TEMPS WILL BE A LITTLE WARMER INTO THE LOW 80S.
1210 AM EST MON NOV 30 2015 HIGH PRESSURE WILL CROSS THE REGION TONIGHT THROUGH MONDAY.
815 PM PST SUN NOV 29 2015 TEMPERATURES WILL WARM TO ABOVE NORMAL BY MID-WEEK AS HIGH PRESSURE BUILDS ALOFT AND OFFSHORE FLOW CONTINUES. A TROUGH OF LOW PRESSURE WILL BRING COOLING AND A CHANCE OF RAIN LATE IN THE WEEK. WARM AND DRY WEATHER WILL LIKELY RETURN FOR THE WEEKEND AS A RIDGE OF HIGH PRESSURE MOVES INTO PLACE AND OFFSHORE FLOW REDEVELOPS. FORECAST MODELS CONTINUE TO SHOW UPPER LEVEL RIDGE OF HIGH PRESSURE GRADUALLY BUILDING OVER THE REGION.
LATEST RADAR REFLECTIVITY DATA CONTINUES TO INDICATE WHAT APPEARS TO BE A DIFFUSE COLD FRONT PUSHING SLOWLY EASTWARD INTO NE ALABAMA. DESPITE THE WEAK NATURE OF THE COLD FRONT. DIFFUSE COLD FRONT WILL CONTINUE TO DISSIPATE ACROSS NRN ALABAMA OVERNIGHT.
SW FLOW WAS OVER MUCH OF THE SERN US AS A CLOSED UPPER LOW CONTINUES TO DEVELOP OVER THE NRN ROCKIES.
THE CLOSED LOW WHICH HAS BEEN SPINNING OVER THE GREAT BASIN IS FINALLY LOOKING TO MAKE ITS EXIT BY TOMORROW AFTERNOON. THIS ENHANCED ACTIVITY IS MOVING RATHER QUICKLY AS THE LOW PRESSURE SYSTEM TAKES FLIGHT TO THE NORTHEAST. WHICH CORRELATES WELL WITH THE COLD FRONTAL PASSAGE AND WIND SHIFT TO NORTHWESTERLY WINDS OVERNIGHT.
SUBSIDENCE ASSOCIATED WITH THE UTAH RIDGE WAS STRONGEST OVER NW CO. THE HIGH PRESSURE RIDGE REMAINS PARKED OVER THE CENTRAL ROCKIES TO THE GREAT BASIN. TEMPERATURES WILL AGAIN REACH INTO THE TRIPLE DIGITS IN THE LOWER DESERT VALLEYS. ALSO OVERNIGHT LOWS WILL BE ON THE WARM SIDE DUE TO THE HIGHER DEW POINTS. THE RIDGE AGAIN SHIFTS EAST AND MOVES OVER THE FOUR CORNERS DURING THE WEEKEND. BY MON THE HIGH CENTER IS PROGGED TO BE JUST TO OUR EAST. WITH PLENTY HIGHS REACHING 100 DEGREES OR BETTER IN THE LOWER DESERT VALLEYS. NIGHTTIME LOWS MAY BE A LITTLE COOLER MIDWEEK AND BEYOND AS THE AIR MASS DRIES OUT.
941 PM CDT MON JUN 29 2015 WILL CONTINUE TO KEEP THE FAIRLY HIGH CLOUD GRIDS FOR MUCH OF THE NIGHT AS WE ARE STILL GETTING THE HIGH LEVEL SMOKE TRANSPORTED DOWN FROM THE CANADIAN FIRES. THE LOWERED VIS WITH LOWER LEVEL SMOKE WILL STAY TO OUR WEST SO WILL KEEP THE MENTION OUT OF THE GRIDS FOR NOW. TEMPS SHOULD BE COOLER THAN TODAY WITH MORE CLOUDS AND PERSISTENT SMOKE.
1127 PM EDT MON JUN 29 2015 WEAK HIGH PRESSURE WILL BUILD ACROSS THE REGION FROM THE WEST OVERNIGHT THEN MOVE EAST TUESDAY. LOW PRESSURE FROM THE GREAT LAKES WILL APPROACH TUESDAY NIGHT.
BECOME QUITE UNSETTLED OVER THE NEXT SEVERAL DAYS AS UPPER LEVEL DISTURBANCES TRAVERSE THROUGH THE LONGWAVE TROUGH SET UP OVER THE EASTERN CONUS.
EXPECT VFR CONDITIONS TO PREVAIL TONIGHT INTO TUESDAY EVEN AS SHOWERS DEVELOP LATE TONIGHT INTO TUES MORNING ACROSS PORTIONS OF THE RIO GRANDE VALLEY AS A WEAK 500MB LOW/INVERTED TROUGH ACROSS NORTHEAST MEXICO CONTINUES TO BRING LOW TO MID LEVEL MOISTURE ACROSS THE WESTERN GULF OF MEXICO INTO THE CWA. VISIBLE SATELLITE LOOPS SHOW ON GOING CONVECTION OFF THE EASTERN COAST OF MEXICO WHICH IS SLOWLY DRIFTING NORTHWARD AS SOUTH TO SOUTHEASTERLY FLOW STRENGTHENS BETWEEN BROAD HIGH PRESSURE OVER THE EASTERN GULF AND LOWER PRESSURE ACROSS THE BAY OF CAMPECHE.
WHICH WILL CONTINUE TO ROLL SOUTHWARD TONIGHT ALLOWING A WEAK BACK DOOR COLD FRONT TO MOVE INTO NORTHWEST IOWA. 12Z UPPER AIR ANALYSIS INDICATED 594 DM RIDGE CENTERED OVER THE GREAT BASIN. AND ANTICYCLONIC FLOW AROUND THE HIGH OVER THE GREAT LAKES WILL BE PROVIDING OUR FA WITH A GOOD DEAL OF DRY AIR. HAVE ALSO COOLED THE HIGHS FOR WED THROUGH FRI WITH THE CWA WITHIN THE INFLUENCE OF THE COOL HIGH TO THE NORTHEAST.
TEMPS WERE RANGING FROM THE LOW TO MID 80 UNDER SCT/BKN CLOUD COVER. THE UPPER AIR PATTERN HAS A RIDGE OVER THE WRN US AND A TROF ACROSS THE ERN 1/2 OF THE COUNTRY.
BUT THEN THE RIDGE AXIS TO OUR SOUTH WILL SHIFT NORTH SOME LATER IN THE WEEK.
SCATTERED THUNDERSTORMS CURRENTLY FIRING OVER THE HIGHER TERRAIN OF NORTHERN ARIZONA AND MOVING WEST INTO THE VALLEYS. DRIVEN BY THE STRONGEST COMPLEXES CURRENTLY MOVING OFF THE HIGHER TERRAIN.
801 PM EDT MON JUN 29 2015 LOW PRESSURE WILL WEAKEN AS IT MOVES ACROSS NORTHERN OHIO TONIGHT LEAVING A WEAK FRONTAL BOUNDARY OVER THE REGION. AN UPPER LEVEL TROUGH WILL PASS OVER THE AREA ON TUESDAY CONTINUING THE ACTIVE WEATHER.
747 PM EDT MON JUN 29 2015 A WEAK LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL MOVE INTO THE REGION TODAY INTO TONIGHT. A WARM FRONT ALSO EXTENDED EAST FROM THE LOW RIGHT AROUND THE OHIO RIVER. A WEAK COLD FRONT THEN EXTENDED SOUTHWEST FROM THE LOW INTO KENTUCKY. ALONG THE WARM FRONT SFC TO 1 KM SRH WAS AROUND 200 M2/S2. STORMS HAVE ALSO STARTED TO FIRE ALONG THE COLD FRONT IN THE HIGHER INSTABILITY JUST SOUTH OF THE AREA. THE WARM FRONT HAS STARTED TO PULL NORTH AND IN THE WARM SECTOR CAPE VALUES HAVE RAPIDLY STARTED TO RISE.
1258 AM EDT TUE JUN 30 2015 ATLANTIC HIGH PRESSURE WILL RESIDE ACROSS THE AREA WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND.
PERIODIC SHOWERS ARE EXPECTED TO CONTINUE TONIGHT AS A WARM FRONT MOVES NORTH ACROSS THE UPPER OHIO VALLEY. BROAD UPPER TROUGH WILL DOMINATE THE EASTERN CONUS THROUGH MID- WEEK. BUT THESE SHOULD WANE QUICKLY AS THEIR SUPPORTING UPPER WAVE DEPARTS AND DRIVES THE ASSOCIATED COLD FRONT SOUTHWARD.
A BROAD UPPER LEVEL LONGER WAVE-LENGTH RIDGE WILL CONTINUE ACROSS THE WESTERN US WITH A DOWNSTREAM LONGER WAVE-LENGTH UPPER TROUGH ACROSS THE EAST CENTRAL US. THE UPPER RIDGE WILL BEGIN TO BUILD EASTWARD INTO THE SOUTHERN HIGH PLAINS. SOUTHWESTERLY SURFACE AND 850MB WINDS WILL ADVECT WARMER AIR NORTHEAST ACROSS THE CWA. THE EASTERN COUNTIES OF THE CWA WILL BE A BIT COOLER WITH HIGHS IN THE LOWER TO MID 90S EXPECTED. DUE TO DEEPER MIXING (820-840MB), DEWPOINTS SHOULD MIX DOWN INTO THE LOWER TO MID 60S DURING THE AFTERNOON HOURS.