Aikyam-Lab/Synoptic-Bench huggingface dataset:
AN APPARENT WEAK UPPER TROUGH OVER SOUTH CENTRAL COLORADO HAS HAS SOME INCREASING THUNDERSTORM ACTIVITY THIS AFTERNOON. TUESDAY WILL BE A COOLER DAY. SO ANY THUNDERSTORMS SHOULD BE LIMITED TO THE HIGH COUNTRY.
WITH DEW POINT TEMPERATURES STILL IN THE 20S AND 30S ACROSS SE CALIFORNIA AND PORTIONS OF THE LOWER COLORADO RIVER VALLEY. AN UPPER LEVEL LOW DRIFTING WESTWARD OVER NORTHERN MEXICO AND THE GULF OF CALIFORNIA WILL AID IN THE INCREASE OF MOISTURE NORTHWARD INTO ARIZONA AND NEW MEXICO OVER THE NEXT 12-18 HOURS.
STRONGER SOUTHWEST FLOW ALOFT TODAY DUE TO A TROUGH PASSING WELL TO OUR NORTH HAS LED TO GENERALLY DRY CONDITIONS AND BREEZY DAYTIME WINDS. AS THIS TROUGH SHIFTS OFF TO THE NORTH AND EAST. HIGH PRESSURE WILL RE-ESTABLISH ACROSS THE REGION OVER THE NEXT FEW DAYS.
TRIED TO CAPTURE THE HIGHER POPS EXPECTED NEXT 6 HOURS. EXPANDED THE HIGH WIND WATCH EAST THROUGH THE CWA. MODELS DELAYED THE HIGHER WINDS ABOUT 3 TO 6 HOURS.
UPPER RIDGE APPEARS TO BE LOSING SOME OF ITS GRIP ON THE AREA AS A FEW SHOWERS HAVE BEEN ABLE TO DEVELOP THIS AFTERNOON. BELIEVE WE WILL SEE THIS AGAIN FOR TUESDAY AS RIDGE SLOWLY BEGINS TO RETROGRADE. THIS FEATURE LOOKS TO CONTINUE MOVING THROUGH THE PERIPHERY OF THE MID LEVEL RIDGE.
LARGE SCALE UPPER LONGWAVE TROF CONTINUES TO PROGRESS ACROSS THE PACIFIC NORTHWEST TOWARD THE NORTHERN ROCKIES. BEFORE THE LARGER SCALE TROF AND SURFACE FRONT PROGRESS EASTWARD TOWARD SUNRISE. SHORT AND MID TERM GUIDANCE PLACES THE COLD FRONT ORIENTED FROM SOUTHWEST TO NORTHEAST, BISECTING THE CWA NEAR 00Z.
TROUGH AXIS HAS NOW MOVED JUST EAST OF OUR CWA. BREEZY AMD COOL THIS AFTERNOON AS DEEP SHORT WAVE TROUGH PASSES THROUGH. TROUGH WILL BE IN MONTANA THIS EVENING AND NORTH OF N.
SOUTHERLY FLOW DEVELOPING IN THE LOWER LEVELS ALONG WITH ANOTHER CLUSTER OF CONVECTION TO THE NORTHWEST MOVING IN. THIS COMBINED WITH THE WEAK DISTURBANCES MOVING OVER THE RIDGE AND INTO THE AREA WILL ALLOW FOR SHOWER AND THUNDERSTORM DEVELOPMENT INTO THE DAY ON TUESDAY. THE MID LEVEL RIDGE AXIS WILL SHIFT OVER THE AREA BRINGING AN END TO ANY CONVECTION AND ALLOWING SOME CLEARING FOR TUESDAY NIGHT BEFORE THE NEXT FRONT BEGINS TO MOVE INTO THE AREA.
648 PM CDT Mon Jul 27 2015 Very little change to the going forecast this afternoon, with excessive heat expected to continue through mid week, before some relief arrives with the approach of a cold front. Starting out this afternoon, isolated thunderstorms have again developed over the eastern Ozarks, where large scale subsidence associated with the upper ridge doesn't appear to be quite strong enough to squash all updrafts.
BETTER UPPER LEVEL FORCING AND A COLD FRONT WILL TRACK ACROSS THE REGION. BULK SHEAR WILL INCREASE AS THE UPPER LEVEL TROUGH APPROACHES.
TEMPERATURES RANGE FROM THE MID TO UPR 80S ACROSS THE HIGHER ELEVATIONS OF NORTH GA TO THE MID TO UPR 90S ACROSS SOUTH-CENTRAL GA. THE CWA REMAINS ON THE EASTERN EDGE OF THE UPPER LEVEL RIDGE WITH A TROUGH TO THE EAST OVER THE ATLANTIC COAST. THE RIDGE AXIS SLIDES EASTWARD IN THE SHORT TERM WITH THE RIDGE BUILDING SLIGHTLY ACROSS THE CWA. HEAT INDICES WILL CLIMB INTO THE LOW 100S ACROSS MUCH OF THE CWA HOWEVER THEY ARE FORECAST TO REMAIN BELOW HEAT ADVISORY CRITERIA /105/. A LOW LVL TROUGH AXIS/BOUNDARY WILL EXIST SOMEWHERE ACROSS GEORGIA DURING THIS TIME AND IS NOT EXPECTED TO MOVE MUCH AS THE FEATURE GETS CAUGHT BETWEEN TWO UPR LVL HIGH PRESSURE SYSTEMS.
AN UPPER RIDGE BUILDING IN FROM THE WESTERN GULF COAST UP THROUGH THE UPPER MIDWEST AND WESTERN WI. RICH MOISTURE AND DEWPOINTS IN THE LOW TO MID 70S THIS AFTERNOON WILL LEND ITSELF TO ANOTHER MUGGY AND WARM EVENING. WEAK CONVERGENT BOUNDARY WILL STILL BE LOCATED IN SOUTHWEST PART OF CWA TUESDAY SO WILL KEEP A SLIGHT CHANCE OF PCPN IN THE AFTERNOON ALONG THAT AN JUST AHEAD OF THE APPROACHING COLD FRONT IN THE NORTHWEST.
WITH A WEAK SFC BOUNDARY UP IN THE LOWER OH VALLEY. /ISSUED 309 PM CDT MON JUL 27 2015/ LATEST RADAR IMAGERY THIS AFTERNOON SHOWS CONVECTION HAS HAD A HARD TIME DEVELOPING ACROSS OUR CWA DUE TO STRENGTHENING UPPER RIDGE. MAIN STORY IS THE HEAT WITH TEMPERATURES IN THE LOW TO MID 90S AND DEWPOINTS IN THE UPPER 60S TO MID 70S LEADING TO HEAT INDEX VALUES CURRENTLY IN THE 100-105 RANGE.
PRIOR TO A WIND SHIFT TO NORTH AROUND 15Z WITH PASSAGE OF COLD FRONT. /ISSUED 334 PM CDT MON JUL 27 2015/ SYNOPTIC SCALE CHANGES ARE EVIDENT IN LATEST WATER VAPOR WITH DEEP TROUGH MOVING EAST TOWARD THE NORTHERN PLAINS AND MONSOON MOISTURE PLUME SHIFTING SLIGHTLY WESTWARD. PREVIOUSLY MENTIONED UPPER TROUGH WILL FORCE A WEAK COLD FRONT SOUTHWARD INTO THE AREA TOMORROW.
LOWS TONIGHT WILL BE IN THE LOWER TO UPPER 70S ACROSS MUCH OF THE AREA. UPPER HEIGHTS AND THE LOW-LEVEL THERMAL PROFILE SLIGHTLY INCREASE AND HIGHS TOMORROW WILL BE NEAR OR A DEGREE OR TWO WARMER THAN TODAY.
/ISSUED 216 PM CDT MON JUL 27 2015/ There's been little change in forecast reasoning with models continuing to support a transitory substropical ridge over the next few days, i. Convection in this pattern will again be mostly favored in mtns/adjacent plains, but noticing some subtlies like secondary mid level theta-e ridge axes and theta-e gradients may help placement of PoPs. Recently 7h temps have been around 14C on 00Z MAF sounding with deterministic model consensus that 7h temps will decrease to around 11C by 00Z/Fri which would yield high temps about 4-6 degrees cooler than yesterday/today for most areas by Thur PM. There's a better chance of precip across the PB Sat/Sun with the NW position of the ridge, even seen on DGEX. Subtropical ridge will attempt to move back ewd late in the forecast which would start temps trending back up.
AS LOW PRESSURE AND SURFACE BOUNDARY WEAKEN AND RETREAT NORMAL. /ISSUED 445 PM EDT MON JUL 27 2015/ AS THIS PAST WEEKEND'S EASTERN GULF LOW PRESSURE CONTINUED TO SLIGHTLY WEAKEN AND DRIFT NORTH, DRIER MIDLEVEL AIR HAS FILLED THE GAP COVERING THE SOUTHEASTERN THIRD OF THE REGION. ALTHOUGH SUBTLE LOW PRESSURE REMAINS NEARBY NORTH FLORIDA MUCH OF THIS WEEK, WITH SOUTHWEST FLOW OVER OUR REGION, ENOUGH RELATIVELY DRIER AIR WILL REMAIN IN THE MIDLEVELS TO KEEP POPS MOSTLY BELOW 50 PERCENT FOR MUCH OF THE WEEK. CONDS A LITTLE MORE FAVORABLE ACROSS THE LAKE REGION AND PALM BEACH COUNTY, SO THAT IS WHERE THE HIGHEST POPS WILL RESIDE.
A COLD FRONT WILL BRING MUCH COOLER TEMPERATURES TO NORTHERN AND CENTRAL UTAH THROUGH THE FIRST PART OF THE WEEK. HIGH PRESSURE WILL RETURN FOR THE LATTER HALF OF THE WEEK WITH MOISTURE BEGINNING TO SEEP INTO SOUTHERN UTAH LATE IN THE WEEK THROUGH THE WEEKEND. THE SURFACE COLD FRONT WHICH SURGED THROUGH NORTHERN UT THIS MORNING CURRENTLY STRETCHES FROM ROUGHLY GREEN RIVER WESTWARD TO ROUGHLY BEAVER. A MUCH COOLER AIRMASS HAS SPREAD INTO NORTHERN UT BEHIND THIS BOUNDARY. A MID LEVEL RIDGE CURRENTLY CENTERED ACROSS THE SOUTHERN PLAINS IS FORECAST TO EXPAND WESTWARD DURING THE MIDWEEK PERIOD ALLOWING FOR A QUICK WARMUP.
The 7 pm EDT regional surface analysis showed a broad, weak, NON- tropical low pressure system centered near Cross City. There was a northeast-southwest oriented trough across central GA.
/ISSUED 309 PM CDT MON JUL 27 2015/ LATEST RADAR IMAGERY THIS AFTERNOON SHOWS CONVECTION HAS HAD A HARD TIME DEVELOPING ACROSS OUR CWA DUE TO STRENGTHENING UPPER RIDGE. MAIN STORY IS THE HEAT WITH TEMPERATURES IN THE LOW TO MID 90S AND DEWPOINTS IN THE UPPER 60S TO MID 70S LEADING TO HEAT INDEX VALUES CURRENTLY IN THE 100-105 RANGE.
1041 PM EDT MON JUL 27 2015 HIGH PRESSURE REMAINS OFFSHORE THROUGH MIDWEEK.
AND AN ASSOCIATED COLD FRONT APPROACHES OUR NORTHWEST CORNER. THE COLD FRONT IS EXPECTED TO REACH THE NORTHWEST CORNER OF THE FORECAST AREA LATE THIS AFTERNOON. NIGHTTIME TEMPS SHOULD BE SOMEWHAT COOLER THAN THE WARM READINGS SEEN LAST NIGHT ESPECIALLY NORTH. WARMER AIR WILL GRADUALLY ADVECT BACK INTO THIS REGION DURING THE DAY ON TUESDAY AS THE CENTER OF LOW PRESSURE OVER THE NORTHERN TIER STATES OF THE CONTIGUOUS US MOVES EAST. WEAK HIGH PRESSURE WILL KEEP WINDS LIGHT ACROSS THE REGION TUESDAY NIGHT. BROAD HIGH PRESSURE OVER THE SOUTHERN TIER OF THE US WILL STRENGTHEN AND ITS CENTER OF CIRCULATION WILL GRADUALLY MOVE WEST TOWARD THE GREAT BASIN BY THE END OF THE WEEK.
930 PM EDT MON JUL 27 2015 A WEAK TROUGH MOVES THROUGH TONIGHT. HIGH PRESSURE BUILDS OVER THE REGION FOR THE MID WEEK.
/ISSUED 247 PM CDT MON JUL 27 2015/ UPPER-LEVEL RIDGE MAINTAINING HOT CONDITIONS ACROSS THE REGION FOR THIS AFTERNOON. RUSTON AND MONROE HAVE THE HIGHEST READINGS AT 107 AND 108 DEGREES.
That feature may also interact with the low level jet to produce a few thunderstorms. Very little change to the going forecast this afternoon, with excessive heat expected to continue through mid week, before some relief arrives with the approach of a cold front. Starting out this afternoon, isolated thunderstorms have again developed over the eastern Ozarks, where large scale subsidence associated with the upper ridge doesn't appear to be quite strong enough to squash all updrafts.
MODELS IN GOOD AGREEMENT WITH PUSHING A COLD FRONT THROUGH THE CWA FROM NW TO SE DURING TUESDAY. NAM ON THE HIGHER END AM LEANING TOWARDS IT SINCE IT IS INITIALIZING WELL.
732 PM EDT MON JUL 27 2015 HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE AREA FROM THE NORTH THROUGH TUESDAY.
TUESDAY WILL BE DRY AND COOL WITH DAYTIME HIGHS 10 TO 15 DEGREES COOLER COMPARED TO TODAY. THEN COOLER READINGS FOR THE REST OF THE WORK WEEK FOLLOWING THE PASSAGE OF A COLD FRONT TONIGHT. THERE IS SOME UNCERTAINTY AS TO WHERE THUNDERSTORMS WILL ACTUALLY DEVELOP BUT A PUNCH OF DRY AIR AHEAD OF AN UPPER LEVEL TROUGH OVER THE NORTHERN ROCKIES WILL LIKELY BE THE TRIGGER WHICH SETS OFF THUNDERSTORMS TODAY.
651 PM CDT MON JUL 27 2015 FOR 00Z TAFS /ISSUED 251 PM CDT MON JUL 27 2015/ CURRENT WATER VAPOR IMAGERY SHOWS THE BROAD UPPER RIDGE OVER MUCH OF THE CENTRAL CONUS. WITH ONE TROUGH DEEPENING INTO NEW ENGLAND. AND ANOTHER TROUGH DIGGING INTO THE UPPER ROCKY MOUNTAINS. THE CENTER OF THE UPPER LEVEL RIDGE WILL SHIFT SLIGHTLY TO THE NORTHEAST AND BECOME CENTERED OVER THE OZARKS ON TUESDAY. GIVEN THE LOWER CONFIDENCE.
STRONG COLD FRONT HAS SWEPT THROUGH EAST IDAHO. TEMPERATURES THE MAIN CONCERN FOR OVERNIGHT WITH LOW ELEVATION AREAS OUTSIDE THE SNAKE PLAIN SEEING THE POTENTIAL FOR LOWS NEAR FREEZING.
THE UPPER AIR PATTERN EARLY THIS EVENING IS DEFINED BY A MEANDERING UPPER LOW OVER THE SOUTHERN BAJA PENINSULA. A MID- LEVEL RIDGE CENTERED ROUGHLY OVER OKLAHOMA. AND A LARGE TROUGH AXIS PIVOTING EASTWARD ACROSS THE NORTHERN ROCKIES.
MODELS SHOW WEAK LOW PRESSURE NEAR THE WEST CENTRAL FL COAST MOVING GRADUALLY NORTHWARD INTO THE NE GULF TONIGHT. MAY SEE PREDOMINANT MVFR CIGS DEVELOP AGAIN TONIGHT DUE TO PROXIMITY OF LOW PRESSURE NEAR THE WESTERN SIDE OF THE FL PENINSULA.
HAVE GONE WITH COOLER TEMPERATURES ON TUESDAY THAN TODAY. A COLD FRONTAL PASSAGE AND A S/W TROF SHOULD GENERATE CONVECTION ACROSS MOST OF THE REGION TUESDAY NIGHT. WITH PERHAPS RENEWED DEVELOPMENT ALONG THE COLD FRONT OVER EASTERN WI OVERNIGHT.
HAVE OPTED TO UPDATE THE FORECAST UNDER THE ASSUMPTION THAT THE MODELS ARE MOVING OUT THE UPPER LEVEL TROUGH ABOUT 4 TO 8 HOURS SLOWER THAN WHAT ACTUALLY APPEARS TO BE HAPPENING. UPPER LEVEL TROUGH OVER CENTRAL MONTANA CONTINUES TO MOVE SLOWLY EAST. WIDESPREAD RAIN AND SCATTERED THUNDERSTORMS ON LEADING EDGE OF TROUGH WILL AFFECT EASTERN ZONES INCLUDING KHVR AND KLWT TERMINALS WITH IFR/MVFR CONDITIONS THROUGH LATE TONIGHT. SCATTERED SHOWERS AND AREAS LIGHT RAIN BEHIND THE TROUGH WITH MVFR/VFR CONDITIONS EXPECTED TO CONTINUE OVERNIGHT.
734 PM EDT MON JUL 27 2015 A WEAK TROUGH MOVES THROUGH TONIGHT. HIGH PRESSURE BUILDS OVER THE REGION FOR THE MID WEEK.
A NON-TROPICAL AREA OF LOW PRESSURE SPINS OFF THE COAST OF WEST CENTRAL FLORIDA THIS EVENING. SHOWER AND THUNDERSTORM ACTIVITY HAS DIMINISHED OTHER THAN A BAND RUNNING FROM THE BIG BEND OF FLORIDA TOWARDS THE LOW OFFSHORE AND SOME ACTIVITY AROUND THE TAMPA BAY AREA.
WE SHOULD SEE ANOTHER ROUND OF VALLEY FOG LATER TONIGHT GIVEN THE HIGH DEW POINTS AND LIGHT FLOW. CLUSTERS OF CONVECTION HAVE ERUPTED IN THE VERY UNSTABLE ENVIRONMENT IN THE LOWER OH AND MID MS VALLEYS.
CLOUDS RETURN OVERNIGHT MAINLY ALONG AND EAST OF I-35 AS TEMPERATURES COOL WITH DEWPOINTS IN THE LOW TO MID 70S. EXPECT ANOTHER WARM AND HUMID SUMMER DAY ON TUESDAY ACROSS SOUTH CENTRAL TEXAS BUT NOT AS HOT AS TODAY (1-2 DEGREE RANGE COOLER). THE UPPER LEVEL HIGH IS FORECAST TO SHIFT TO THE EAST AND WEAKENS A BIT WHILE AN INVERTED UPPER LEVEL TROUGH PUSHES FROM EAST TO WEST ACROSS THE AREA. LOWS TONIGHT WILL BE IN THE LOWER TO UPPER 70S ACROSS MUCH OF THE AREA. UPPER HEIGHTS AND THE LOW-LEVEL THERMAL PROFILE SLIGHTLY INCREASE AND HIGHS TOMORROW WILL BE NEAR OR A DEGREE OR TWO WARMER THAN TODAY.
WEAK LOW PRESSURE CONTINUES TO DRIFT NORTH THROUGH THE EASTERN GULF OF MEXICO/WEST COAST OF FL. AS LOW PRESSURE AND SURFACE BOUNDARY WEAKEN AND RETREAT NORMAL. /ISSUED 445 PM EDT MON JUL 27 2015/ AS THIS PAST WEEKEND'S EASTERN GULF LOW PRESSURE CONTINUED TO SLIGHTLY WEAKEN AND DRIFT NORTH, DRIER MIDLEVEL AIR HAS FILLED THE GAP COVERING THE SOUTHEASTERN THIRD OF THE REGION. ALTHOUGH SUBTLE LOW PRESSURE REMAINS NEARBY NORTH FLORIDA MUCH OF THIS WEEK, WITH SOUTHWEST FLOW OVER OUR REGION, ENOUGH RELATIVELY DRIER AIR WILL REMAIN IN THE MIDLEVELS TO KEEP POPS MOSTLY BELOW 50 PERCENT FOR MUCH OF THE WEEK. CONDS A LITTLE MORE FAVORABLE ACROSS THE LAKE REGION AND PALM BEACH COUNTY, SO THAT IS WHERE THE HIGHEST POPS WILL RESIDE.
WITH A STRONG MID LEVEL RIDGE ANCHORED OVER NORTHWEST TEXAS AND WESTERN OKLAHOMA. AND HIGH PRESSURE OVER THE CENTRAL AND WEST GULF. WITH HIGH TEMPS FROM THE LOWER 90S ALONG THE COAST.
COLD FRONT EXPECTED TO ARRIVE AROUND 17Z TUESDAY AT NORTHERN TERMINALS WITH SURFACE WINDS INITIALLY SHIFTING TO NORTH AND THEN EAST NORTHEAST DURING THE AFTERNOON.
/ISSUED 324 PM CDT MON JUL 27 2015/ WX MAP SHOWING FAIRLY STAGNATE HIGH PRESSURE OVER THE N GULF. WITH HIGH PRESSURE ALOFT OVER E TX/LA/MS. MAYBE A DEGREE OR SO COOLER THAN YESTERDAY AT THIS TIME. WITH THE RIDGE STILL OVERHEAD. A WEAK SFC TROF ACROSS THE EASTERN GULF AND AN APPROACHING COOL FRONT WILL YIELD BETTER COVERAGE OF SHRA/TSRA. NOT MUCH IF ANY COOLER TEMPS EXPECTED WITH THIS FRONT.
A WARMING TREND IS EXPECTED BY MID WEEK AS HIGH PRESSURE STRENGTHENS. THE GOLDEN STATE IS BASKING UNDER SUNNY SKIES AND SEASONABLE TEMPERATURES THIS AFTERNOON THANKS TO A DRY WESTERLY FLOW ALOFT THAT IS CURRENTLY UNDERCUTTING AN UPPER LEVEL TROUGH OVER THE NORTHERN ROCKIES.
915 PM PDT MON JUL 27 2015 DRY WEATHER CONTINUES THIS WEEK WITH TEMPERATURES RETURNING TO WELL ABOVE AVERAGE AS HIGH PRESSURE STRENGTHENS. HIGH PRESSURE BUILDING OVER THE REGION THE NEXT COUPLE OF DAYS WILL HELP TO HEAT UP THE REGION.
1038 PM EDT MON JUL 27 2015 A WEAK TROUGH MOVES THROUGH TONIGHT. HIGH PRESSURE BUILDS OVER THE REGION FOR THE MID WEEK.
TONIGHT THROUGH SUNDAY AS THE UPPER LOW CONTINUES TO SPIN OVER COLORADO. IT WILL CONTINUE TO WRAP SOME MORE MOISTURE AROUND THE LOW INTO EASTERN PORTIONS OF THE FORECAST AREA THROUGH THE NIGHT. THERE WILL BE SOME LOWERING SNOW LEVELS AS A COLD FRONT DROPS DOWN FROM THE NORTH EARLY THIS EVENING ALONG WITH A SHORT WAVE DROPPING OUT OF CANADA. MOST AREAS WILL NOTICE GUSTY NORTH WINDS AND COOLER TEMPERATURES ALONG WITH THE FRONT EARLY IN THE PERIOD BUT THERE WILL BE A FEW SHOWERS AND STORMS OCCURRING WEST OF THE MAIN CLOUD SHIELD FROM OUR RESIDENT LOW. THE BACK SIDE OF OUR KICKER TROUGH WILL BE OVER THE AREA WITH A FEW GUSTY NORTHWEST WINDS CONTINUING ALONG WITH COOLER TEMPERATURES BUT OVERALL IT WILL BE A DRIER DAY.
MOSTLY CLEAR SKIES AND WARMING TEMPERATURES ARE EXPECTED THROUGH THE REMAINDER OF THE WEEKEND WITH DESERT HIGHS CLIMBING INTO THE LOW 90S BY SUNDAY.
259 PM CDT SAT APR 18 2015 PERSISTENT UPPER LOW SPINNING OVER EASTERN COLORADO THIS AFTERNOON PROGGED BY OPERATIONAL MODELS TO WEAKEN INTO AN OPEN WAVE AS IT ADVECTS EAST INTO EASTERN KANSAS BY SUNDAY EVENING. A SERIES OF FAST MOVING SHORT WAVE TROUGHS WILL CONTINUE TO MOVE ACROSS FORECAST AREA DURING THIS TIME. AS UPPER TROUGH AXIS MOVES THROUGH EARLY SUNDAY. SURFACE COLD FRONT WILL SURGE QUICKLY THROUGH THE FORECAST AREA WITH A STOUT NORTH WIND IN ITS WAKE.
WINDS WILL BE VARIABLE WITH SOUTHEAST TO SOUTHWEST OVER THE SOUTHEAST SIDE OF THE LOW PRESSURE AREA AND NORTHEAST TO NORTHERLY AROUND THE BACK SIDE AS IT LIFTS NORTHEAST. THE UPPER LOW IS SLOWLY EDGING OFF THE FOUR CORNERS INTO CO/NB/KN NOW THANKS TO ANOTHER DEEPENING TROUGH ON THE NW COAST. THE COLD FRONT WILL NOT ARRIVE UNTIL LATE AFTERNOON SUNDAY AND INTO THE EVENING. SO TODAY LOOKS MORE FAVORABLE FOR WIDE SPREAD COVERAGE WITH ONLY A MARGINAL RISK FOR SEVERE AND THEN ON SUNDAY WE ARE SLIGHT/ENHANCED FOR SEVERE WITH THE COLD FRONT BY MORE LIMITED WIDE SPREAD COVERAGE. OUR DEW POINTS WILL BE LOW TO MID 60S WITH SOME MORE HEATING AHEAD OF THE FRONT ARRIVING WITH SOME LIFT WHILE STILL UNDER THE UPPER DIVERGENT TROUGH TO OUR WEST.
BUILDING UPPER RIDGE OVER FORECAST AREA THROUGH TONIGHT. MAINLY ALONG WARM FRONT MOVING NORTHWARD OVER SRN GA AND FL SEA BREEZES.
403 PM EDT SAT APR 18 2015 HIGH PRESSURE OVER THE AREA TODAY WILL BEGIN TO PULL EAST AND WASHOUT AS AN UPPER LEVEL LOW OVER THE ROCKIES MOVES EAST.
427 PM CDT SAT APR 18 2015 BROAD UPPER TROUGH CONTINUES TO SPIN OVER THE HIGH PLAINS OF ERN COLORADO. THE LARGE UPPER LOW WILL MOVE EWD ACROSS THE PLAINS AND A COLD FRONT WILL DIVE SEWD.
WEAK SURFACE COLD FRONT FROM THE NORTHWEST HAS NOT COOLED TEMPS BUT NORTHWEST WINDS HAVE INCREASED. DUE TO THE ASSOCIATED SHORT WAVE TROUGH ALOFT.
/ISSUED 628 AM CDT SAT APR 18 2015/ A LARGE UPPER LEVEL LOW PRESSURE SYSTEM CONTINUES TO SPIN ACROSS THE INTERMOUNTAIN WEST THIS MORNING WHILE SLOWLY LIFTING TO THE NORTHEAST. THE AIRMASS OVER THE FORECAST AREA WILL BECOME SLIGHTLY UNSTABLE AS DEWPOINTS REMAIN IN THE LOWER 60S AND TEMPERATURES RISE INTO THE MIDDLE AND UPPER 70S. AS THE UPPER LEVEL LOW LIFTS NORTHEAST AND TRANSITIONS TO AN OPEN WAVE ON SUNDAY. THE MID LEVEL HEIGHT FALLS ASSOCIATED WITH THE UPPER TROUGH SHOULD ERODE ANY RESIDUAL EARLY DAY CAPPING AND ALLOW FOR SCATTERED TO NUMEROUS THUNDERSTORMS DEVELOPING ACROSS THE WARM SECTOR. ALONG AND AHEAD OF AN APPROACHING SURFACE COLD FRONT THAT WILL MOVE THROUGH THE REGION SUNDAY NIGHT.
The lack of any notable wind shear that far from the mid level trough should keep the storms from being too rowdy, but with a few small hail reports through the day, they are demonstrating some ability to be strong. By early Sunday morning the low will finally be more influenced by the mid level flow and eject out into the area during the day. Accompanying the wave will be a surface cold front which will effectively scour out the usable moisture, thus ending precipitation chances with its passage. Convergence aloft on the backside of an upper trough over the northern Great Lakes/Canadian border, along with moisture to work with could allow for showers and some thunderstorms to affect primarily the southern half of the forecast area through the end of the week.
A COLD FRONT WILL MOVE ACROSS THE TERMINALS THIS EVENING. /ISSUED 457 AM CDT SAT APR 18 2015/ A CLOSED UPPER LOW ALONG THE CENTRAL CO/NM BORDER EARLY THIS MORNING WILL MOVE SLOWLY EAST TODAY.
1006 AM MST SAT APR 18 2015 LOOK FOR WARMER DAYTIME TEMPERATURES AS THE LATEST WEATHER SYSTEM MOVES EASTWARD.
328 PM MDT SAT APR 18 2015 THE LOW PRESSURE RESPONSIBLE FOR THE MUCH NEEDED PRECIP OVER THE LAST FEW DAYS IS NOW LOCATED OVER THE FRONT PLAINS WHILE CYCLONIC FLOW CONTINUES TO PUMP IN MOISTURE FROM THE NORTH TO SOUTH. AN UPPER LEVEL DISTURBANCE OVER SRN CANADA IS TRAILING A TROUGH THAT IS CAUSING THE AREA OF LOW PRESSURE TO KEEP MOVING EWRD. THE CLOUD SHIELD/PLUME WILL BRING MORE PRECIP TO THE AREA AS THE ATTENDANT LOW PRESSURE MEANDERS EAST. THE CANADIAN LOW WILL BE JUST TO THE NORTH OF MINNESOTA WHILE HIGH PRESSURE BUILDS INTO THE PACNW.
IN GENERAL THE HIGHEST POTENTIAL FOR ANY REDEVELOPMENT WOULD BE FOUND IN THE WARM SECTOR SOUTHWEST OF THE CWA. LOWER POPS DURING THE EARLY OVERNIGHT HOURS BEGIN TO INCREASE SLIGHTLY LATE THIS EVENING AND TOWARDS MIDNIGHT AHEAD OF 850MB TROUGH AXIS.
WE WILL BE WATCHING THE EVOLUTION OF THE LARGE UPPER-LEVEL LOW AND ASSOCIATED TROUGH THAT IS FORECAST TO MOVE EASTWARD INTO THE CENTRAL PLAINS ON SUNDAY. IN THE MID/UPPER LEVELS THE TROUGH WILL MOVE ACROSS THE EASTERN U.
1116 AM PDT SAT APR 18 2015 A weak cold front has moved through the region overnight and will produce slightly cooler temperatures and some breezy winds for the weekend.
/ISSUED 351 PM CDT SAT APR 18 2015/ AS AN UPPER TROUGH CENTERED OVER THE CENTRAL PLAINS MOVES EAST THIS AFTERNOON AND OVERNIGHT IT WILL INFLUENCE SHOWERS AND THUNDERSTORMS TO CONTINUE THEIR TREK NORTHWARD THROUGH MIDDLE TN. BUT CLOUDS SHOULD BREAK UP ENOUGH DURING THE AFTERNOON HOURS TO ALLOW FOR TEMPERATURES TO WARM INTO THE LOW 70S ALONG THE CUMBERLAND PLATEAU AND MID 70S ELSEWHERE.
1243 PM CDT Sat Apr 18 2015 Overview: Closed and cut-off upper low now over central CO will be the primary weather driver for the weekend. Today - Sunday: While eyes have been fixated on the closed upper low now over CO/NM the real weather makers will be periodic vorticity lobes and associated layered frontogenesis that rotate northeast out from under the upper low. Even still this is a forecast which will need adjusting throughout the day as the convection tied to the upper low has had repeated false starts as well as expanding too fast to the east. The upper low will have opened up by then and will accelerate eastward. Anticipate convection increasing as it moves east through the CWA in response to improving upper level dynamics and low-level convergence associated with a cold front.
700 PM EDT SAT APR 18 2015 HIGH PRESSURE OVER CENTRAL ONTARIO WILL BUILD TO THE EASTERN GREAT LAKES TONIGHT. LOW PRESSURE WILL TRACK FROM THE GULF COAST TO THE CENTRAL GREAT LAKES ON SUNDAY PULLING A WARM FRONT NORTHWARD ACROSS THE AREA.
1233 PM CDT SAT APR 18 2015 ANOTHER UNSETTLED DAY IS EXPECTED ACROSS THE REGION AS THE UPPER LEVEL LOW ACROSS COLORADO CONTINUES TO SLOWLY PUSH EASTWARD. EXPECT A COLD FRONT TO WORK ITS WAY DOWN FROM THE NORTH. THE UPPER LOW FINALLY MOVES THROUGH THE AREA SUNDAY MORNING. THE UPPER LOW STARTS TO OPEN AS IT MOVES THROUGH. THE MAIN TROUGH IS THROUGH THE AREA BY MID DAY. COOLER AIR MOVES IN BEHIND THE UPPER LOW AND EXPECT COOLER TEMPERATURES SUNDAY NIGHT.
344 PM EDT SAT APR 18 2015 HIGH PRESSURE OVER CENTRAL ONTARIO WILL BUILD TO THE EASTERN GREAT LAKES TONIGHT. LOW PRESSURE WILL TRACK FROM THE GULF COAST TO THE CENTRAL GREAT LAKES ON SUNDAY PULLING A WARM FRONT NORTHWARD ACROSS THE AREA.
244 PM EDT SAT APR 18 2015 A DEEP LAYER AREA OF HIGH PRESSURE IS SLOWLY MOVING EASTWARD ACROSS THE EASTERN GULF OF MEXICO. AHEAD OF AN UPPER LOW AND TROUGH SLIDING DOWN THE FRONT RANGE OF COLORADO. WITH THE RIDGE IN PLACE OVER THE EASTERN GULF WE FIND THE KEYS ENGULFED IN MOSTLY SUNNY SKIES AND LIGHT SOUTHEAST TO SOUTH WINDS. NO CHANGES TO THE FORECAST THIS CYCLE WITH THE SLOW PROGRESSION OF THE UPPER LOW INTO THE CENTRAL PLAINS AND MISSISSIPPI VALLEY THROUGH SUNDAY. SUNDAY NIGHT AS THE TROUGH APPROACHES. THE UPPER TROUGH WILL LIFT TO THE NORTHEAST.
WINDS WILL BE GUSTY FROM THE NORTHWEST WITH A COLD FRONT AT 20 TO 30 MPH. HIGHS WILL BE IN THE LOW TO MID 60S. A RIDGE OF HIGH PRESSURE SETTLES INTO WESTERN KANSAS SUNDAY NIGHT WITH LIGHT NORTHWEST WINDS AND MOSTLY CLEAR SKIES.
1145 AM MDT SAT APR 18 2015 AVIATION SECTION UPDATED COLD FRONT HAS PENETRATED MOST OF NORTH-CENTRAL MONTANA THIS MORNING. RADAR SHOWS AN AREA OF PRECIPITATION BECOMING MORE WIDESPREAD BEHIND THE COLD FRONT. PRECIPITATION WILL END QUICKLY AS THE TROF PASSES.
LOOK FOR WARM FRONTAL MOISTURE TO BEGIN ADVECTING INTO MIDDLE TENNESSEE AFTER 00Z, WITH LIGHT PRECIPITATION DEVELOPING DURING THE EVENING, AND THEN BECOMING HEAVIER WITH WORSENING CEILINGS OVERNIGHT AND LASTING INTO TOMORROW. THE TROUGH MOVING UP FROM THE SOUTHWEST WILL START TO IMPACT THE REGION WITH PRECIP THIS AFTERNOON. THERE IS A CHANCE THAT SOME ISOLATED CELLS WILL BE AHEAD OF THE COLD FRONT IN THE WARM SECTOR. HOWEVER THERE IS A BETTER CHANCE FOR A MORE LINEAR CONVECTIVE MODE WITH THE APPROACHING COLD FRONT.
238 PM EDT SAT APR 18 2015 WARM FRONT CROSSES THIS EVENING. UPPER TROUGH AXIS SUNDAY.