Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/02/15


AREA FORECAST DISCUSSION
NWS ALBANY NY
158 PM EDT TUE MAR 31 2015 .SYNOPSIS... A DISTURBANCE PASSING TO OUR SOUTH...WILL BRING LIGHT PRECIPITATION TO SOUTHERN PARTS OF THE ALBANY FORECAST AREA LATER TODAY INTO THIS EVENING...INCLUDING SOME MINOR SNOW ACCUMULATIONS NEAR THE INTERSTATE 84 CORRIDOR. HIGH PRESSURE WILL BRING SUNSHINE BUT COOL WEATHER WEDNESDAY. AS THE HIGH MOVES EAST ON THURSDAY...A SOUTHERLY FLOW AND MAINLY DRY WEATHER SHOULD GIVE THE ALBANY AREA ITS FIRST 50 DEGREE DAY OF 2015. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 145 PM...ECHOES ON AREA RADARS SHOWING LARGER AREA OF PRECIPITATION THAN SURFACE SENSORS. PRECIPITATION REACHING THE GROUND EXTENDS NORTHWARD TO JUST NORTH OF THE NY/PA BORDER AND EAST TO ABOUT THE PA/NJ BORDER. NEAREST REPORT OF SNOW AT MONTICELLO NY IN SULLIVAN COUNTY WHERE LIGHT SNOW WAS FALLING. TEMPERATURES IN THE MID HUDSON VALLEY ARE QUITE MILD WITH TEMPS IN THE MID AND UPPER 40S. PRECIPITATION WILL LIKELY BEGIN AS RAIN IN THE VALLEY WITH SNOW IN THE HIGHER ELEVATIONS OF THE SOUTHEASTERN CATSKILLS. LATEST HRRR SEEMS TO HAVE A GOOD HANDLE ON THE LEADING EDGE OF THE PRECIPITATION...IT SHOULD JUST BE STARTING IN THE SOUTHEASTERN CATSKILLS...AND HAS THE PRECIPITATION ENDING IN THE MID HUDSON VALLEY AND SOUTHERN LITCHFIELD COUNTY BY 11 PM THIS EVENING. LITTLE IF ANY PRECIPITATION EXPECTED NORTH OF ULSTER...DUTCHESS AND LITCHFIELD COUNTIES. LATEST UPDATE CONTAINS A FIRST GUESS FOR ALL MODEL FIELDS OUT TO 12Z FRIDAY INCLUDING FIRE WEATHER GRIDS. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... THE DISTURBANCE...WHICH WILL TRACK SOUTH OF THE MASON/DIXON LINE...WILL MOVING OFF THE SOUTHERN NEW JERSEY COASTLINE THIS EVENING...AND THEN OUT TO SEA. TRAILING DEFORMATION BEHIND THE LOW CENTER COULD KEEP PRECIPITATION GOING INTO THE EVENING HOURS NEAR THE I-84 CORRIDOR. AS WE LOOSE DAYLIGHT AND CONTINUE TO COOL FURTHER...ALL PRECIPITATION WILL TURN SNOW BY DARK. THERE IS A POTENTIAL OF 1-2 INCHES OF ACCUMULATION NEAR THE I-84...MAYBE UP TO 3 INCHES ACROSS THE CATSKILLS OF ULSTER COUNTY. WE WILL MONITOR THIS POSSIBLE BUT EVEN IF IT HAPPENS...AMOUNTS WOULD BE TOO LIGHT FOR EVEN A SNOW ADVISORY. STILL...SOME ROADS COULD BECOME LOCALLY SLICK THIS EVENING NEAR I-84. THE VAST MAJORITY OF THE REGION WILL REMAIN DRY WITH THINNING CLOUDS TONIGHT. TEMPERATURES WILL DIP INTO THE 20S...WITH SOME TEENS ACROSS THE ADIRONDACKS. THE WIND WILL NORTHWEST BE 5-15 MPH. WEDNESDAY AS HIGH PRESSURE BUILDS INTO THE REGION...IT WILL BE ANOTHER ONE OF THE MAINLY SUNNY DAYS WITH A DEEP BLUE SKY. IT WILL BE CHILLIER THAN NORMAL BUT THE SUNSHINE WILL HELP COACH TEMPERATURES TO AROUND 40 OR A LITTLE BETTER IN MOST VALLEY AREAS...MID OR UPPER 30S HIGHER TERRAIN. WE WILL HAVE A NORTHWEST WIND PERSISTING 10-20 MPH. WEDNESDAY NIGHT HIGH PRESSURE WILL CREST OVER THE REGION...WITH A MAINLY CLEAR SKY. TEMPERATURES WILL DIP BACK INTO THE LOWER TO MID 20S ALBANY SOUTH...TEENS FURTHER NORTH AND WEST. THURSDAY...A SOUTHERLY BREEZE COMBINED WITH EARLY APRIL SUNSHINE SHOULD FINALLY END OUR UNDER 50 DEGREE TEMPERATURE AT 96 DAYS. WHILE THAT INTERVAL ITSELF IS NOT EVEN CLOSE TO THE LONGEST SUCH RECORD...IT WILL BE OUR SECOND LATEST DAY IN ANY GIVEN SEASON TO OFFICIALLY REACH 50 OR HIGHER. WE ARE FORGETTING HIGHS IN THE MID 50S IN AND AROUND THE CAPITAL REGION...UPPER 40S TO LOWER 50S WELL NORTH OF ALBANY...AND PERHAPS UPPER 50S WELL SOUTH OF ALBANY. A FEW LIGHT SHOWERS MIGHT BRUSH THE WESTERN ADIRONDACKS BUT THESE WOULD BE VERY LIGHT AND JUST RAIN SHOWERS. THURSDAY NIGHT...A SOUTHERLY BREEZE WILL INCREASE...ALONG WITH CLOUDS AND THE THREAT OF SHOWERS OUT AHEAD OF STRONG FRONT PRESSING IN FROM THE WEST. THIS WILL KEEP TEMPERATURES UP QUITE A BIT...WITH LOWS GENERALLY 45-50 ALBANY SOUTHWARD...MID 30S TO LOWER 40S NORTH AND WEST OF ALBANY. && .LONG TERM /FRIDAY THROUGH MONDAY/... A SPRINGLIKE DAY ON FRIDAY AHEAD OF (UNFORTUNATELY) ANOTHER COLD FRONT THAT WILL BE MOVING THROUGH THE REGION. HIGHS ON FRIDAY WILL BE IN THE 50S TO LOWER 60S...WITH SOME UPPER 40S OVER THE ADIRONDACKS WHERE THE COLD FRONT MOVES THROUGH FIRST. THERE WILL ALSO BE A GOOD CHANCE OF SHOWERS AS THE FRONT MOVES THROUGH AND HAVE FORECAST POPS OF 50 PERCENT. BOTH THE ECMWF AND GFS NOW FORECAST A SIGNIFICANT WAVE TO FORM ALONG THE FRONT AND BRING WIDESPREAD PCPN TO THE ALBANY FORECAST AREA FRIDAY NIGHT INTO EARLY SATURDAY. THE MAIN DIFFERENCE BETWEEN THE MODELS IS THE TRACK OF THE LOW. ECMWF TRACKS THE LOW OVER ALBANY AS IT MOVES EAST-NORTHEAST...THEREBY KEEPING CONDITIONS OVER THE ALBANY FORECAST AREA RATHER MILD AND PCPN MAINLY IN THE FORM OF RAIN UNTIL NEARLY THE END OF THE EVENT. THE GFS TRACKS THE LOW OFF THE NEW JERSEY COAST WITH ENOUGH COOLING OVER THE REGION FOR RAIN TO CHANGE TO SNOW IN MOST AREAS AFTER MIDNIGHT. WITH BOTH MODELS INDICATING WIDESPREAD PCPN LIKELY... HAVE FORECAST LIKELY POPS IN ALL AREAS FRIDAY NIGHT. FOR PCPN TYPE...HAVE BLENDED THE TWO SOLUTIONS WHICH RESULTS IN UP TO A FEW INCHES OF SNOW ACCUMULATION ACROSS HIGHER TERRAIN AREAS...AND A DUSTING TO AN INCH IN LOWER TERRAIN AREAS FROM THE CAPITAL DISTRICT NORTH AND WEST...AND NO SNOW IN VALLEY AREAS SOUTH OF ALBANY. LOWS FRIDAY NIGHT WILL BE IN THE 30S TO LOWER 40S MOST AREAS...AND MID TO UPPER 20S OVER THE ADIRONDACKS AND HIGHER TERRAIN OF THE SOUTHERN GREEN MOUNTAINS. THE UPPER LEVEL TROF AND ANOTHER COLD FRONT MOVING THROUGH SATURDAY NIGHT WILL KEEP THE THREAT OF PCPN ACROSS THE REGION SATURDAY AND SATURDAY NIGHT. HAVE ONLY FORECAST 30 TO 40 PERCENT POPS ON SATURDAY...AND SLIGHT OR LOW CHANCE POPS SATURDAY NIGHT ACROSS AREAS WEST OF THE HUDSON VALLEY. HIGHS SATURDAY WILL BE IN THE MID 30S TO THE 40S. LOWS SATURDAY NIGHT GENERALLY IN THE 20S TO LWOER 30S...EXCEPT THE TEENS OVER THE ADIRONDACKS AND SOUTHERN GREEN MOUNTAINS. A SMALL HIGH PRESSURE AREA WILL BRING DRY BUT COLDER THAN NORMAL WEATHER TO THE REGION SUNDAY AND SUNDAY NIGHT. HIGHS SUNDAY WILL BE IN THE 30S TO MID 40S. LOWS SUNDAY NIGHT IN THE 20S TO LOWER 30S...AND TEENS ADIRONDACKS. A WARM FRONT WILL BRING THE THREAT OF LIGHT PCPN TO THE CENTRAL AND NORTHERN PART OF THE FORECAST AREA ON MONDAY. HIGHS MONDAY WILL BE IN THE 40S TO LOWER 50S...EXCEPT UPPER 30S OVER THE ADIRONDACKS. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... HAVE FORECAST VFR CONDITIONS AT THE KGFL/KALB/KPSF TAF SITES FOR THE ENTIRE TAF PERIOD ENDING AT 18Z WEDNESDAY. AT KPOU...HAVE FORECAST VFR CONDITIONS THROUGH OOZ...WITH SOME RAIN ARRIVING AROUND 19Z...THEN MVFR CIGS/VSBYS BETWEEN OOZ AND 03Z AS RAIN CHANGES TO SNOW. AFTER 03Z...SOME MVFR POSSIBLE AT KPOU WITH FOG. VFR CONDITIONS EXPECTED ALL LOCATIONS WEDNESDAY. WINDS GENERALLY BE FROM THE NORTH OR NORTHWEST AT 5 TO 10 KNOTS THROUGH THE PERIOD. .FIRE WEATHER... IT WILL START OUT DRY TODAY AND MOST AREAS WILL REMAIN THAT WAY. THE ONLY EXCEPTION WILL BE OUR SOUTHERN AREAS FROM ABOUT KINGSTON SOUTH WHERE A FAST MOVING ESE MOVING DISTURBANCE WILL BRING A LITTLE LIGHT PRECIPITATION...INITIALLY AS VALLEY RAIN AND A SNOW/RAIN IN THE MOUNTAINS. AS WE HEAD TOWARD DARK...PRECIPITATION WILL CHANGE TO ALL SNOW EVERYWHERE WITH A MINOR ACCUMULATION OF 1-3 INCHES POSSIBLE. RH VALUES WILL BE HIGHEST SOUTH WHERE THE PRECIPITATION HAPPENS...BUT EVEN THERE BEFORE IT MOVES THIS AFTERNOON...RH VALUES WILL DROP ABOUT ABOUT 60 PERCENT...OTHERWISE LOOK FOR VALUES 35 TO 50 PERCENT THIS AFTERNOON. ANY SNOW OR RAIN ENDS THIS EVENING...FOLLOWING BY PARTIAL CLEARING BUT SOMEWHAT BREEZY CONDITIONS WHICH MEANS A FULL RECOVERY WILL LIKELY NOT HAPPEN. WEDNESDAY LOOKS MAINLY SUNNY AND BRISK WITH A NORTHWEST WIND 10-15 MPH. AFTERNOON RH VALUES WILL GENERALLY BE FAIRLY LOW IN THE 30-40 PERCENT RANGE. CLEAR AND COLD WEDNESDAY NIGHT WITH A NORMAL RECOVERY. THURSDAY LOOKS MAINLY DRY WITH A SOUTH WIND INCREASING TO 10-20 MPH BY AFTERNOON AND RH VALUES IN THE LOW RANGE EXCEPT MODERATE RANGE ACROSS THE ADIRONDACKS. THE CHANCE FOR PRECIPITATION WILL THURSDAY NIGHT INTO FRIDAY...STARTING OUT AS ALL RAIN...BUT CHANGING TO SNOW IN SOME AREAS BEFORE ENDING BY LATE SATURDAY. && .HYDROLOGY... NO HYDRO RELATED PROBLEMS ARE ANTICIPATED THROUGH AT LEAST WEDNESDAY. WELL ABOVE NORMAL TEMPERATURES ARE POSSIBLE ON THURSDAY AND FRIDAY WHICH WOULD BRING ABOUT WIDESPREAD SNOW MELT. A LARGE STORM SYSTEM MAY IMPACT THE REGION FRIDAY INTO SATURDAY WITH MODERATE AMOUNTS OF RAIN...WHICH WOULD LEAD TO SIGNIFICANT RIVER RISES AND PERHAPS A FEW ICE JAMS MAINLY NORTH OF THE MOHAWK RIVER. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...SND/HWJIV NEAR TERM...SND SHORT TERM...SND/HWJIV LONG TERM...GJM AVIATION...GJM FIRE WEATHER...HWJIV/NAS HYDROLOGY...SND/HWJIV/NAS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1240 PM EDT TUE MAR 31 2015 .SYNOPSIS... LOW PRESSURE WILL QUICKLY TRACK SOUTHEASTWARD FROM THE GREAT LAKES REGION, CROSSING OUR AREA LATER TODAY INTO THIS EVENING. HIGH PRESSURE WILL THEN BUILD INTO OUR REGION WEDNESDAY BEFORE QUICKLY SHIFTING OFFSHORE WEDNESDAY NIGHT INTO THURSDAY. THE NEXT COLD FRONT IS SCHEDULED TO ARRIVE LATE FRIDAY, WITH A SECONDARY COLD FRONT MOVING THROUGH LATE SATURDAY NIGHT AND SUNDAY MORNING. A HIGH PRESSURE SYSTEM IS THEN NEARBY FOR MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1230 PM UPDATE...ALTHOUGH AN INITIAL BAND OF TRACE FLURRIES AND SPRINKLES HAVE MOVED INTO THE NW PORTIONS OF THE CWA, THE MAIN BAND OF STEADY PRECIP HAS BEEN SLOWER TO PROGRESS EAST THAN PREVIOUSLY FORECAST. ALSO, WITH THE LATER ARRIVAL OF THE PRECIP, TEMPERATURES ARE WELL ABOVE GUIDANCE, WITH MOST LOCATIONS (OUTSIDE OF THE POCONOS) RANGING FROM THE MID 40S TO LOWER 60S...INCLUDING SUSSEX COUNTY NJ. THEREFORE EVEN THOUGH THERE IS THE POTENTIAL FOR SOME ACCUMULATING SNOW IN NW NJ, ESPECIALLY IF THEY SEE HIGHER SNOW RATES WITH A MESOSCALE BAND, THE TEMPERATURES SHOULD HINDER ANY SIGNIFICANT ACCUMULATION, SO HAVE CANCELLED THE ADVISORY THERE. THE ADVISORY REMAINS IN EFFECT FOR THE POCONOS. 9:30 AM UPDATE: WITH THIS UPDATE MADE SOME CHANGES TO ACCOUNT FOR A PRETTY QUICK RISE IN TEMPERATURES ACROSS SOUTHERN PARTS OF THE REGION. THIS WILL LIKELY CONTINUE INTO THIS AFTERNOON WITH DECENT WAA SOUTH OF THE CLIPPER TRACK. ALSO WITH THE WAA, THE NAM AND HRRR ARE SHOWING SOME INSTABILITY IN THE FORM OF STEEP LAPSE RATES AND CAPE BETWEEN 200-500 J/KG ACROSS THE DELMARVA LATE THIS AFTERNOON. THIS COULD BE THE TRIGGER FOR A THUNDERSTORM OR TWO, SO HAVE ADDED THIS TO THE GRIDS SOUTH OF ILG. SNOW PART OF THE FORECAST LOOKS MAINLY ON TRACK WITH THE CHANGEOVER FROM RAIN TO SNOW OCCURRING EARLY AFTERNOON FOR THE POCONOS AND THE HIGHER ELEVATIONS IN SUSSEX NJ. LIGHTER ACCUMULATIONS HAVE BEEN TRIMMED BACK IN MORRIS NJ AND FOR THE LEHIGH VALLEY/READING. TEMPERATURES IN THESE AREAS ARE ALREADY IN THE UPPER 30`S AND LOW 40`S WITH 1-2 OF ADDITIONAL WARMING BEFORE PRECIPITATION STARTS. WIND GUSTS AROUND 20-25 MPH COUPLED WITH RH VALUES AROUND 35% ARE FORECASTED IN THE SOUTHERN DELMARVA FOR A FEW HOURS, WITH RAIN IN THE FORECAST THIS AFTERNOON DO NOT SEE ANY FIRE WEATHER CONCERNS ATTM. 8:00 AM: FORECAST STILL LOOKS ON TRACK FOR A LIGHT ACCUMULATING SNOWFALL IN THE HIGHER TERRAIN OF SUSSEX NJ AND THE POCONOS TODAY WITH A PERIOD OF RAIN OR RAIN/SNOW MIX ELSEWHERE. SLOWED THE INCREASE OF CLOUDS SOMEWHAT OVER THE NEXT FEW HOURS THOUGH. THE PRECIPITATION ONSET TIME MAY NEED TO BE PUSHED BACK BY 1-2 HOURS AS WELL BASED ON THE LATEST RAP AND HRRR RUNS. ATTM DID NOT MAKE THIS ADJUSTMENT WITH THE POSSIBILITY STILL PRESENT OF RAIN/ MIX ENTERING THE WESTERN FRINGE OF THE CWA BY 16-17Z. IN THE POCONOS AND NW NJ, THE PRECIPITATION MAY START AS A MIX BEFORE CHANGING TO SNOW WITH EVAPORATIVE COOLING OCCURRING. PREVIOUS: THE GFS INITIALIZATION LOOKED A LITTLE WEAK WITH THE APPROACHING TROF AND MAYBE WHY ITS TIMING IS THE FASTEST. ITS SLIGHTLY WARMER AT 925MB UPSTREAM THAN THE MODELS THINK. OVERALL THE MODELS ARE MUCH CLOSER THAN THEY WERE YESTERDAY, BUT THERE REMAINS DIFFERENCES AS TO THE NORTHERN EXTENT OF HEAVIER PCPN. THEY HAVE TRENDED COLDER AND OVERALL WETTER. MODEL PREDICTED PWATS HOWEVER ARE AROUND HALF AN INCH AND GIVEN THIS IS ABOUT A 6 TO 12 HR EVENT, BELIEVE QPF ABOVE HALF AN INCH ARE TOO ROBUST UNLESS A FGEN BAND CONCENTRATES IN A NARROW AREA FOR A PROTRACTED PERIOD. OUR FORECAST SOLUTION IS CLOSEST TO A COMBINATION OF THE UKMET`S QPF FIELD, GFS PATH (COUPLE OF HOURS SLOWER) AND WRF-NMM`S BETTER LLVL THERMALS AND SFC TEMPS FOR THE NORTHERN SNOWIER AREAS. WINTER WEATHER ADVISORY FOR OUR THREE NORTHERN COUNTIES. IF THIS WAS NIGHTTIME THIS WOULD BE MORE OF A CONFIDENT SNOWFALL FCST, BUT GIVEN THIS IS A TIMING REPEAT OF MARCH 20TH, THERE REMAINS UNCERTAINTY AS TO HOW MUCH SNOW CAN ACCUMULATE. MARCH 20TH SHOWED INTENSITY CAN TRUMP THE LATE MARCH SUN. THE HOURLY RATES AT PEAK TIME DURING THIS AFTERNOON IS NEARING .1 WATER EQUIVALENT PER HOUR. THIS SHOULD BE ENOUGH TO START ACCUMULATING. BUT THIS OVERALL WINDOW IS SMALLER THAN THAT PREVIOUS EVENT. ALSO THE INITIAL BOUNDARY LAYER CAN WARM THIS MORNING AND THIS WILL PROLONG THE CHANGE TO SNOW AT LOWER TERRAIN LOCATIONS. THE HIGHER TERRAIN OF THE POCONOS AND WESTERN SUSSEX COUNTY NJ IT WILL BE PRETTY MUCH COLD ENOUGH FOR SNOW. THE UNCERTAINTY IS TO WILL THE HEAVIER PCPN REACH THAT FAR NORTH. THE GENERAL CONSENSUS IS YES, BUT THERE IS NOT UNIFORMITY. THE GFS DIAGS DO SHOW FGEN BANDING IN THAT AREA, BUT THE EXIT REGION OF THE 250MB JET AND BEST MID LEVEL QVEC CONVERGENCE IS A BIT FTHR TO THE SOUTH. THERE WILL BE A 45 KT LLJ FEEDING ACROSS THIS BOUNDARY AND THERE IS A BROAD 200MB OF LIFT PREDICTED AT 290K ACROSS OUR CWA THIS AFTERNOON. HERE GOES, PCPN MOVES IN NORTH LATE THIS MORNING AND EARLY THIS AFTERNOON AND LATER IN THE AFTERNOON THE REST OF OUR CWA. THE SOUNDINGS ARE DRY ABOVE THE SFC AND EVAP COOLING SHOULD CHANGE ANY BRIEF START OF RAIN IN THE HIGHER TERRAIN OF THE POCONOS TO SNOW. ELSEWHERE ITS THE LESS EFFICIENT DYNAMIC COOLING THAT IS EXPECTED TO DO THE TRICK. OBVIOUSLY ELEVATION HELPS AS THE GFS PREDICTED FREEZING LEVEL AT ABE DROPPING TO 800 FEET SHOWS. ALL THE MODELS LOWER SFC TEMPS AND WBZS TO AROUND FREEZING IN THE POCONOS, BUT STRUGGLE ELSEWHERE. SO THERE IS GREATER UNCERTAINTY FARTHER EAST IN SUSSEX COUNTY NJ. THE NEXT TIER SOUTHWARD, THERE COULD BE SOME HIGHER TERRAIN LOCATIONS THAT DO GET A COUPLE OF INCHES, NOT AS WIDESPREAD AS THE ADVISORY AREA WE BELIEVE. WE WILL HAVE TO WATCH IF THE FGEN BANDING ESTABLISHES ITSELF IN THIS LOCATION LATER TODAY, BUT CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE AN ADVISORY. WE WILL KEEP MENTION IN THE HWO. TEMPERATURES ARE ALSO PROBLEMATICAL AS THE GFS LOWER TEMPS ARE BANKING ON A FASTER PCPN ARRIVAL TIME. GIVE ITS ARRIVAL UNTIL THE AFTERNOON AND NAM MOS MAY BE RIGHT FOR THE WRONG REASON. WE COMPROMISED BETWEEN THE DATASETS. 06Z MODELS PRETTY MUCH HELD THEIR OWN. E.G. ABE FREEZING LEVEL LATE THIS AFTERNOON AT 800 TO 900 FEET. 06Z MODEL QPF VERIFICATION GEOGRAPHICALLY WAS GOOD WITH THE GFS AND NAM A BIT WET. GFS ENSEMBLE MEAN WAS SLIGHTLY SLOWER THAN THE OP. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... OPTING FOR THE SLOWER MODEL TIMING, WE CARRIED PCPN INTO THIS EVENING, ESPECIALLY IN NJ. EVENT SHOULD BE DONE BY ABOUT MIDNIGHT. THE PREDICTED VORT MAX OVERNIGHT BECOMES QUITE CHANNELIZED AND MODELS PREDICTED MOISTURE OVERALL MEAGER. WE CLEARED SKIES OVERNIGHT. WE OPTED FOR A STAT GUIDANCE COMPROMISE FOR MINS. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE OVERALL SYNOPTIC SETUP IS AN ACTIVE ONE BUT ALSO COMPRISED OF A FAST FLOW REGIME. AN UPPER-LEVEL TROUGH ACROSS THE NORTHEAST TO START WEDNESDAY WILL SHIFT EAST WITH A RIDGE BUILDING IN THURSDAY AS SHORT WAVE ENERGY MOVES ACROSS THE MIDWEST. THIS SHORT WAVE ENERGY WILL HELP TO AMPLIFY AN UPPER-LEVEL TROUGH ACROSS THE GREAT LAKES AND OHIO VALLEY LATE FRIDAY, THEN INTO THE EAST SATURDAY. IT APPEARS THIS TROUGH REMAINS THROUGH MONDAY, ALTHOUGH IT SHOULD START TO RETREAT NORTHWARD WITH TIME. WE USED A MODEL BLEND FOR WEDNESDAY THROUGH FRIDAY, THEN INCORPORATED THE 00Z WPC GUIDANCE IN WITH CONTINUITY THEREAFTER. SOME ADJUSTMENTS WERE THEN MADE FOLLOWING ADDITIONAL COLLABORATION WITH OUR NEIGHBORING OFFICES. FOR WEDNESDAY AND THURSDAY...AN UPPER-LEVEL TROUGH AXIS IS FORECAST TO PIVOT ACROSS THE AREA WEDNESDAY. A SHORT WAVE ROUNDING THE BASE OF THIS TROUGH MAY HAVE SOME SHOWERS WITH IT TO OUR NORTHWEST, HOWEVER IT MAY END UP DAMPENING OUT AS IT TRACKS SOUTHEAST AND EAST. THEREFORE, WE WILL CONTINUE WITH A DRY FORECAST. SOME CAA AT LEAST DURING THE FIRST HALF OF THE DAY WILL RESULT IN A COOLER DAY. HIGH PRESSURE SHIFTS OFFSHORE WEDNESDAY NIGHT INTO THURSDAY ALLOWING FOR A RETURN FLOW. AS THIS OCCURS, WAA WILL INCREASE AHEAD OF OUR NEXT SYSTEM. THIS WILL BE IN THE FORM OF A COLD FRONT THAT WILL BE APPROACHING LATE THURSDAY NIGHT. AHEAD OF THIS, A NOTABLE INCREASE IN AFTERNOON TEMPERATURES ARE EXPECTED THURSDAY /ALTHOUGH PROBABLY COOLER ALONG THE COAST DUE TO A SOUTHERLY FLOW OFF THE COLDER OCEAN/. IT APPEARS THAT A LEAD SHORT WAVE GENERATES SOME SHOWERS WELL OUT AHEAD OF THE COLD FRONT THURSDAY AND THESE MAY START TO MOVE INTO OUR WESTERN ZONES LATER THURSDAY NIGHT. IT APPEARS THAT IT WILL TAKE AWHILE FARTHER EAST THEREFORE WE SLOWED DOWN THE POP INCREASE AT NIGHT FROM WEST TO EAST. IN ADDITION, THE FORECAST SOUNDINGS GENERALLY SHOW A DEEPENING MOIST PROFILE AS A LOW-LEVEL JET INCREASES THE THETA-E ADVECTION. THIS RESULTS IN A DECREASE IN THE SHOWALTER VALUES, HOWEVER NO REAL INSTABILITY LOOKS TO BE PRESENT. AS A RESULT THERE IS A QUESTION WHETHER OR NOT CHARGE SEPARATION CAN TAKE PLACE AND THEREFORE WE REMOVED THE SLIGHT CHC OF THUNDER ATTM. AS MIXING INCREASES THURSDAY, A BREEZY AFTERNOON SHOULD RESULT. FOR FRIDAY AND SATURDAY...A COLD FRONT WILL GRADUALLY SETTLE SOUTHEAST ACROSS OUR AREA LATER FRIDAY INTO SATURDAY. A WARM SOUTHWESTERLY FLOW WILL BE IN PLACE AND THIS COMBINED WITH LARGE SCALE LIFT FROM THE INCOMING COLD FRONT, UPPER-LEVEL TROUGH AND AN UPPER-LEVEL JET SHOULD RESULT IN SHOWERS OR EVEN BANDS OF SHOWERS. IF ENOUGH INSTABILITY CAN BE REALIZED, SOME THUNDER COULD OCCUR ON FRIDAY AHEAD OF THE COLD FRONT. WE WILL MAINTAIN CONTINUITY AND INCLUDE A SLIGHT CHC OF THUNDER IN THE FORECAST DATABASE. LOW PRESSURE SHOULD BE TRACKING TO OUR NORTH AND NORTHEAST FRIDAY NIGHT, PULLING THE COLD FRONT TO OUR EAST EARLY SATURDAY. AS SOME ENERGY ROTATES AROUND THE BASE OF THE TROUGH, A COUPLE OF WAVES OF LOW PRESSURE SHOULD DEVELOP ALONG THE COLD FRONT. THE FIRST ONE SHOULD DELAY THE COLD FRONTAL PASSAGE ACROSS OUR AREA AND THEN THE SECOND ONE TRACKS WELL TO OUR SOUTH AND EAST AFTER THE FRONT CLEARS OUR AREA EARLY SATURDAY. THE TIMING AND POSITIONING OF THE COLD FRONT FRIDAY WILL IMPACT TEMPERATURES, HOWEVER OUR ENTIRE CWA SHOULD REMAIN IN THE WARM SECTOR. WE THEN KEPT LOW CHC POPS FOR SHOWERS IN FOR SATURDAY THEN DRYING OVERTAKES THE AREA. A SECONDARY COLD FRONT LOOKS TO DROP INTO THE AREA LATE SATURDAY NIGHT. FOR SUNDAY AND MONDAY...A COLD FRONT SHOULD MOVE ACROSS THE AREA SUNDAY MORNING, HOWEVER THIS LOOKS MOISTURE STARVED. HIGH PRESSURE THEN SLIDES TO OUR EAST LATE SUNDAY INTO MONDAY, ALTHOUGH THE TAILEND OF THE AFOREMENTIONED COLD FRONT MAY REMAIN FROM THE OHIO VALLEY WESTWARD TO THE NORTHERN PLAINS. FOR NOW, KEPT THIS TIMEFRAME DRY WITH MODERATION IN TEMPERATURES ON MONDAY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY, AND SURROUNDING AREAS. THE 12Z TAFS STILL BRING ALL OF OUR SITES TO LOW MVFR OR IFR CONDITIONS THIS AFTERNOON WITH A HIGH DEGREE OF UNCERTAINTY ABOUT THE WIND DIRECTIONS THIS AFTERNOON AND EARLY EVENING. THIS MORNING A MID LEVEL CIG ARRIVING, SOME RAIN POSSIBLE LATE AT KABE AND KRDG. SOUTH TO SOUTH WEST WINDS AVERAGING 5 TO 10 KNOTS. THIS AFTERNOON AT KABE AND KRDG CIGS AND VSBYS LOWERING TO IFR. RAIN MAY MIX WITH OR CHANGE TO SNOW LATE. ESP KABE. TARMAC ACCUMS NOT EXPECTED. LOCAL KPHL AIRPORTS RAIN ARRIVES AND CIGS AND VSBYS LOWERING TO THE BORDER BETWEEN MVFR AND IFR CONDITIONS. KMIV AND KACY SIMILAR EVOLUTION, BUT LATER IN THE AFTERNOON. WINDS WILL BE TRICKY AS IT DEPENDS UPON THE TRACK OF THE LOW. WE ARE EXPECTING IT TO PASS TO THE SOUTH OF ALL THE TERMINALS ACROSS DELMARVA. THERE WILL BE A SLOW BACKING OF THE WINDS FROM SOUTH TO NORTHEAST AS THE AFTERNOON PROGRESSES. SPEEDS SHOULD BE AROUND 10 KNOTS. THIS EVENING, CONDITIONS BOTTOMING EAST OT IFR EARLY AND THEN IMPROVING CONDITIONS THE REST OF THE EVENING. PCPN SHOULD END BY 04Z ALL TERMINALS. WINDS WILL CONTINUE TO BACK TOWARD THE NORTH AND THEN NORTHWEST WITH AVERAGE SPEEDS AROUND 10 KNOTS, BUT SOME GUSTINESS TO AROUND 20 KNOTS FROM THE KPHL AIRPORTS SOUTHEASTWARD. OVERNIGHT IMPROVING CONDITIONS CONTINUING WITH A VFR CIG BECOMING CLEAR AND NORTHWEST WINDS AVERAGING AROUND 10 TO 15 KNOTS. OUTLOOK... WEDNESDAY AND THURSDAY...VFR OVERALL. AN INCREASE IN CLOUDS SHOULD OCCUR LATE THURSDAY AHEAD OF A COLD FRONT WITH SHOWERS LURKING NOT TO FAR TO OUR WEST LATE AT NIGHT. GENERALLY LIGHT WINDS WEDNESDAY DUE TO HIGH PRESSURE IN PLACE, THEN A SOUTHERLY FLOW DEVELOPS WEDNESDAY NIGHT AND THURSDAY WITH SOME GUSTINESS DURING THURSDAY. FRIDAY AND SATURDAY...MVFR TO POTENTIALLY IFR CONDITIONS WITH SHOWERS. A THUNDERSTORM CANNOT BE RULED OUT AHEAD OF A COLD FRONT FRIDAY. POTENTIALLY GUSTY SOUTHWESTERLY WINDS FRIDAY, SHIFTING TO THE NORTHWEST FRIDAY NIGHT INTO SATURDAY. SHOWERS SHOULD END SATURDAY MORNING FOLLOWED BY CONDITIONS RETURNING TO VFR. THERE IS LOWER CONFIDENCE REGARDING THE TIMING OF THE CLEARING SATURDAY. && .MARINE... RIGHT NOW CONDITIONS ARE BELOW SCA CRITERIA ON THE OCEAN. HOWEVER BOTH SEAS AND GUSTS ARE EXPECTED TO INCREASE SOME THIS AFTERNOON. WE WILL KEEP THE SCA UP FOR THE POTENTIAL OF WIND GUSTS AROUND 25 KNOTS THIS AFTERNOON AND LOCALIZED SEAS NEAR FIVE FEET. THE ADVISORY IS NOT IN EFFECT FOR DELAWARE BAY, ALTHOUGH THERE COULD BE A FEW GUSTS TO 25 KNOTS THIS MORNING AND AGAIN LATER TONIGHT WITH THE DOWN THE BAY FLOW. WE WILL REACCESS THE BAY LATER TODAY. OUTLOOK... WEDNESDAY...HIGH PRESSURE BUILDS OVER THE AREA BUT THEN BEGINS TO SHIFT OFFSHORE AT NIGHT. AS A RESULT, THE WINDS AND SEAS WILL DECREASE AND BE BELOW ADVISORY CRITERIA. THURSDAY AND FRIDAY...A SOUTH TO SOUTHWEST FLOW WILL INCREASE AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF A COLD FRONT. A MUCH WARMER AIRMASS HOWEVER WILL BE MOVING OVER THE COLDER WATERS, AND THIS WILL LIMIT THE MIXING. AS A RESULT, THE HIGHEST GUSTS WILL PROBABLY BE CLOSER TO THE COAST. THE INCREASING SOUTHERLY FLOW WILL BUILD THE SEAS AND THEREFORE A SMALL CRAFT ADVISORY LOOKS TO BE NEEDED. THE WAVEWATCH GUIDANCE IS PROBABLY OVERDONE SOME WITH THE SEAS AS THE GFS IS A BIT TO STRONG WITH THE SURFACE WINDS, THEREFORE WE STAYED CLOSER TO CONTINUITY WHICH HAD THIS FACTORED IN. SATURDAY...A COLD FRONT SHOULD BE EAST OF OUR AREA WITH A WIND SHIFT TO THE NORTHWEST, AND THE WINDS COULD BE A BIT GUSTY AS SOME COOLING TAKES PLACE. THE SEAS SHOULD BE AT OR ABOVE 5 FEET ON THE OCEAN, BUT TENDING TO SUBSIDE WITH THE OFFSHORE FLOW. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR PAZ054-055. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455. && $$ SYNOPSIS...GORSE NEAR TERM...GAINES/GIGI/JOHNSON SHORT TERM...GIGI LONG TERM...GORSE AVIATION...GIGI/GORSE MARINE...GIGI/GORSE
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
949 AM EDT TUE MAR 31 2015 .SYNOPSIS... LOW PRESSURE WILL QUICKLY TRACK SOUTHEASTWARD FROM THE GREAT LAKES REGION, CROSSING OUR AREA LATER TODAY INTO THIS EVENING. HIGH PRESSURE WILL THEN BUILD INTO OUR REGION WEDNESDAY BEFORE QUICKLY SHIFTING OFFSHORE WEDNESDAY NIGHT INTO THURSDAY. THE NEXT COLD FRONT IS SCHEDULED TO ARRIVE LATE FRIDAY, WITH A SECONDARY COLD FRONT MOVING THROUGH LATE SATURDAY NIGHT AND SUNDAY MORNING. A HIGH PRESSURE SYSTEM IS THEN NEARBY FOR MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 9:30 AM UPDATE: WITH THIS UPDATE MADE SOME CHANGES TO ACCOUNT FOR A PRETTY QUICK RISE IN TEMPERATURES ACROSS SOUTHERN PARTS OF THE REGION. THIS WILL LIKELY CONTINUE INTO THIS AFTERNOON WITH DECENT WAA SOUTH OF THE CLIPPER TRACK. ALSO WITH THE WAA, THE NAM AND HRRR ARE SHOWING SOME INSTABILITY IN THE FORM OF STEEP LAPSE RATES AND CAPE BETWEEN 200-500 J/KG ACROSS THE DELMARVA LATE THIS AFTERNOON. THIS COULD BE THE TRIGGER FOR A THUNDERSTORM OR TWO, SO HAVE ADDED THIS TO THE GRIDS SOUTH OF ILG. SNOW PART OF THE FORECAST LOOKS MAINLY ON TRACK WITH THE CHANGEOVER FROM RAIN TO SNOW OCCURRING EARLY AFTERNOON FOR THE POCONOS AND THE HIGHER ELEVATIONS IN SUSSEX NJ. LIGHTER ACCUMULATIONS HAVE BEEN TRIMMED BACK IN MORRIS NJ AND FOR THE LEHIGH VALLEY/READING. TEMPERATURES IN THESE AREAS ARE ALREADY IN THE UPPER 30`S AND LOW 40`S WITH 1-2 OF ADDITIONAL WARMING BEFORE PRECIPITATION STARTS. WIND GUSTS AROUND 20-25 MPH COUPLED WITH RH VALUES AROUND 35% ARE FORECASTED IN THE SOUTHERN DELMARVA FOR A FEW HOURS, WITH RAIN IN THE FORECAST THIS AFTERNOON DO NOT SEE ANY FIRE WEATHER CONCERNS ATTM. 8:00 AM: FORECAST STILL LOOKS ON TRACK FOR A LIGHT ACCUMULATING SNOWFALL IN THE HIGHER TERRAIN OF SUSSEX NJ AND THE POCONOS TODAY WITH A PERIOD OF RAIN OR RAIN/SNOW MIX ELSEWHERE. SLOWED THE INCREASE OF CLOUDS SOMEWHAT OVER THE NEXT FEW HOURS THOUGH. THE PRECIPITATION ONSET TIME MAY NEED TO BE PUSHED BACK BY 1-2 HOURS AS WELL BASED ON THE LATEST RAP AND HRRR RUNS. ATTM DID NOT MAKE THIS ADJUSTMENT WITH THE POSSIBILITY STILL PRESENT OF RAIN/ MIX ENTERING THE WESTERN FRINGE OF THE CWA BY 16-17Z. IN THE POCONOS AND NW NJ, THE PRECIPITATION MAY START AS A MIX BEFORE CHANGING TO SNOW WITH EVAPORATIVE COOLING OCCURRING. PREVIOUS: THE GFS INITIALIZATION LOOKED A LITTLE WEAK WITH THE APPROACHING TROF AND MAYBE WHY ITS TIMING IS THE FASTEST. ITS SLIGHTLY WARMER AT 925MB UPSTREAM THAN THE MODELS THINK. OVERALL THE MODELS ARE MUCH CLOSER THAN THEY WERE YESTERDAY, BUT THERE REMAINS DIFFERENCES AS TO THE NORTHERN EXTENT OF HEAVIER PCPN. THEY HAVE TRENDED COLDER AND OVERALL WETTER. MODEL PREDICTED PWATS HOWEVER ARE AROUND HALF AN INCH AND GIVEN THIS IS ABOUT A 6 TO 12 HR EVENT, BELIEVE QPF ABOVE HALF AN INCH ARE TOO ROBUST UNLESS A FGEN BAND CONCENTRATES IN A NARROW AREA FOR A PROTRACTED PERIOD. OUR FORECAST SOLUTION IS CLOSEST TO A COMBINATION OF THE UKMET`S QPF FIELD, GFS PATH (COUPLE OF HOURS SLOWER) AND WRF-NMM`S BETTER LLVL THERMALS AND SFC TEMPS FOR THE NORTHERN SNOWIER AREAS. WINTER WEATHER ADVISORY FOR OUR THREE NORTHERN COUNTIES. IF THIS WAS NIGHTTIME THIS WOULD BE MORE OF A CONFIDENT SNOWFALL FCST, BUT GIVEN THIS IS A TIMING REPEAT OF MARCH 20TH, THERE REMAINS UNCERTAINTY AS TO HOW MUCH SNOW CAN ACCUMULATE. MARCH 20TH SHOWED INTENSITY CAN TRUMP THE LATE MARCH SUN. THE HOURLY RATES AT PEAK TIME DURING THIS AFTERNOON IS NEARING .1 WATER EQUIVALENT PER HOUR. THIS SHOULD BE ENOUGH TO START ACCUMULATING. BUT THIS OVERALL WINDOW IS SMALLER THAN THAT PREVIOUS EVENT. ALSO THE INITIAL BOUNDARY LAYER CAN WARM THIS MORNING AND THIS WILL PROLONG THE CHANGE TO SNOW AT LOWER TERRAIN LOCATIONS. THE HIGHER TERRAIN OF THE POCONOS AND WESTERN SUSSEX COUNTY NJ IT WILL BE PRETTY MUCH COLD ENOUGH FOR SNOW. THE UNCERTAINTY IS TO WILL THE HEAVIER PCPN REACH THAT FAR NORTH. THE GENERAL CONSENSUS IS YES, BUT THERE IS NOT UNIFORMITY. THE GFS DIAGS DO SHOW FGEN BANDING IN THAT AREA, BUT THE EXIT REGION OF THE 250MB JET AND BEST MID LEVEL QVEC CONVERGENCE IS A BIT FTHR TO THE SOUTH. THERE WILL BE A 45 KT LLJ FEEDING ACROSS THIS BOUNDARY AND THERE IS A BROAD 200MB OF LIFT PREDICTED AT 290K ACROSS OUR CWA THIS AFTERNOON. HERE GOES, PCPN MOVES IN NORTH LATE THIS MORNING AND EARLY THIS AFTERNOON AND LATER IN THE AFTERNOON THE REST OF OUR CWA. THE SOUNDINGS ARE DRY ABOVE THE SFC AND EVAP COOLING SHOULD CHANGE ANY BRIEF START OF RAIN IN THE HIGHER TERRAIN OF THE POCONOS TO SNOW. ELSEWHERE ITS THE LESS EFFICIENT DYNAMIC COOLING THAT IS EXPECTED TO DO THE TRICK. OBVIOUSLY ELEVATION HELPS AS THE GFS PREDICTED FREEZING LEVEL AT ABE DROPPING TO 800 FEET SHOWS. ALL THE MODELS LOWER SFC TEMPS AND WBZS TO AROUND FREEZING IN THE POCONOS, BUT STRUGGLE ELSEWHERE. SO THERE IS GREATER UNCERTAINTY FARTHER EAST IN SUSSEX COUNTY NJ. THE NEXT TIER SOUTHWARD, THERE COULD BE SOME HIGHER TERRAIN LOCATIONS THAT DO GET A COUPLE OF INCHES, NOT AS WIDESPREAD AS THE ADVISORY AREA WE BELIEVE. WE WILL HAVE TO WATCH IF THE FGEN BANDING ESTABLISHES ITSELF IN THIS LOCATION LATER TODAY, BUT CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE AN ADVISORY. WE WILL KEEP MENTION IN THE HWO. TEMPERATURES ARE ALSO PROBLEMATICAL AS THE GFS LOWER TEMPS ARE BANKING ON A FASTER PCPN ARRIVAL TIME. GIVE ITS ARRIVAL UNTIL THE AFTERNOON AND NAM MOS MAY BE RIGHT FOR THE WRONG REASON. WE COMPROMISED BETWEEN THE DATASETS. 06Z MODELS PRETTY MUCH HELD THEIR OWN. E.G. ABE FREEZING LEVEL LATE THIS AFTERNOON AT 800 TO 900 FEET. 06Z MODEL QPF VERIFICATION GEOGRAPHICALLY WAS GOOD WITH THE GFS AND NAM A BIT WET. GFS ENSEMBLE MEAN WAS SLIGHTLY SLOWER THAN THE OP. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... OPTING FOR THE SLOWER MODEL TIMING, WE CARRIED PCPN INTO THIS EVENING, ESPECIALLY IN NJ. EVENT SHOULD BE DONE BY ABOUT MIDNIGHT. THE PREDICTED VORT MAX OVERNIGHT BECOMES QUITE CHANNELIZED AND MODELS PREDICTED MOISTURE OVERALL MEAGER. WE CLEARED SKIES OVERNIGHT. WE OPTED FOR A STAT GUIDANCE COMPROMISE FOR MINS. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE OVERALL SYNOPTIC SETUP IS AN ACTIVE ONE BUT ALSO COMPRISED OF A FAST FLOW REGIME. AN UPPER-LEVEL TROUGH ACROSS THE NORTHEAST TO START WEDNESDAY WILL SHIFT EAST WITH A RIDGE BUILDING IN THURSDAY AS SHORT WAVE ENERGY MOVES ACROSS THE MIDWEST. THIS SHORT WAVE ENERGY WILL HELP TO AMPLIFY AN UPPER-LEVEL TROUGH ACROSS THE GREAT LAKES AND OHIO VALLEY LATE FRIDAY, THEN INTO THE EAST SATURDAY. IT APPEARS THIS TROUGH REMAINS THROUGH MONDAY, ALTHOUGH IT SHOULD START TO RETREAT NORTHWARD WITH TIME. WE USED A MODEL BLEND FOR WEDNESDAY THROUGH FRIDAY, THEN INCORPORATED THE 00Z WPC GUIDANCE IN WITH CONTINUITY THEREAFTER. SOME ADJUSTMENTS WERE THEN MADE FOLLOWING ADDITIONAL COLLABORATION WITH OUR NEIGHBORING OFFICES. FOR WEDNESDAY AND THURSDAY...AN UPPER-LEVEL TROUGH AXIS IS FORECAST TO PIVOT ACROSS THE AREA WEDNESDAY. A SHORT WAVE ROUNDING THE BASE OF THIS TROUGH MAY HAVE SOME SHOWERS WITH IT TO OUR NORTHWEST, HOWEVER IT MAY END UP DAMPENING OUT AS IT TRACKS SOUTHEAST AND EAST. THEREFORE, WE WILL CONTINUE WITH A DRY FORECAST. SOME CAA AT LEAST DURING THE FIRST HALF OF THE DAY WILL RESULT IN A COOLER DAY. HIGH PRESSURE SHIFTS OFFSHORE WEDNESDAY NIGHT INTO THURSDAY ALLOWING FOR A RETURN FLOW. AS THIS OCCURS, WAA WILL INCREASE AHEAD OF OUR NEXT SYSTEM. THIS WILL BE IN THE FORM OF A COLD FRONT THAT WILL BE APPROACHING LATE THURSDAY NIGHT. AHEAD OF THIS, A NOTABLE INCREASE IN AFTERNOON TEMPERATURES ARE EXPECTED THURSDAY /ALTHOUGH PROBABLY COOLER ALONG THE COAST DUE TO A SOUTHERLY FLOW OFF THE COLDER OCEAN/. IT APPEARS THAT A LEAD SHORT WAVE GENERATES SOME SHOWERS WELL OUT AHEAD OF THE COLD FRONT THURSDAY AND THESE MAY START TO MOVE INTO OUR WESTERN ZONES LATER THURSDAY NIGHT. IT APPEARS THAT IT WILL TAKE AWHILE FARTHER EAST THEREFORE WE SLOWED DOWN THE POP INCREASE AT NIGHT FROM WEST TO EAST. IN ADDITION, THE FORECAST SOUNDINGS GENERALLY SHOW A DEEPENING MOIST PROFILE AS A LOW-LEVEL JET INCREASES THE THETA-E ADVECTION. THIS RESULTS IN A DECREASE IN THE SHOWALTER VALUES, HOWEVER NO REAL INSTABILITY LOOKS TO BE PRESENT. AS A RESULT THERE IS A QUESTION WHETHER OR NOT CHARGE SEPARATION CAN TAKE PLACE AND THEREFORE WE REMOVED THE SLIGHT CHC OF THUNDER ATTM. AS MIXING INCREASES THURSDAY, A BREEZY AFTERNOON SHOULD RESULT. FOR FRIDAY AND SATURDAY...A COLD FRONT WILL GRADUALLY SETTLE SOUTHEAST ACROSS OUR AREA LATER FRIDAY INTO SATURDAY. A WARM SOUTHWESTERLY FLOW WILL BE IN PLACE AND THIS COMBINED WITH LARGE SCALE LIFT FROM THE INCOMING COLD FRONT, UPPER-LEVEL TROUGH AND AN UPPER-LEVEL JET SHOULD RESULT IN SHOWERS OR EVEN BANDS OF SHOWERS. IF ENOUGH INSTABILITY CAN BE REALIZED, SOME THUNDER COULD OCCUR ON FRIDAY AHEAD OF THE COLD FRONT. WE WILL MAINTAIN CONTINUITY AND INCLUDE A SLIGHT CHC OF THUNDER IN THE FORECAST DATABASE. LOW PRESSURE SHOULD BE TRACKING TO OUR NORTH AND NORTHEAST FRIDAY NIGHT, PULLING THE COLD FRONT TO OUR EAST EARLY SATURDAY. AS SOME ENERGY ROTATES AROUND THE BASE OF THE TROUGH, A COUPLE OF WAVES OF LOW PRESSURE SHOULD DEVELOP ALONG THE COLD FRONT. THE FIRST ONE SHOULD DELAY THE COLD FRONTAL PASSAGE ACROSS OUR AREA AND THEN THE SECOND ONE TRACKS WELL TO OUR SOUTH AND EAST AFTER THE FRONT CLEARS OUR AREA EARLY SATURDAY. THE TIMING AND POSITIONING OF THE COLD FRONT FRIDAY WILL IMPACT TEMPERATURES, HOWEVER OUR ENTIRE CWA SHOULD REMAIN IN THE WARM SECTOR. WE THEN KEPT LOW CHC POPS FOR SHOWERS IN FOR SATURDAY THEN DRYING OVERTAKES THE AREA. A SECONDARY COLD FRONT LOOKS TO DROP INTO THE AREA LATE SATURDAY NIGHT. FOR SUNDAY AND MONDAY...A COLD FRONT SHOULD MOVE ACROSS THE AREA SUNDAY MORNING, HOWEVER THIS LOOKS MOISTURE STARVED. HIGH PRESSURE THEN SLIDES TO OUR EAST LATE SUNDAY INTO MONDAY, ALTHOUGH THE TAILEND OF THE AFOREMENTIONED COLD FRONT MAY REMAIN FROM THE OHIO VALLEY WESTWARD TO THE NORTHERN PLAINS. FOR NOW, KEPT THIS TIMEFRAME DRY WITH MODERATION IN TEMPERATURES ON MONDAY. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY, AND SURROUNDING AREAS. THE 12Z TAFS STILL BRING ALL OF OUR SITES TO LOW MVFR OR IFR CONDITIONS THIS AFTERNOON WITH A HIGH DEGREE OF UNCERTAINTY ABOUT THE WIND DIRECTIONS THIS AFTERNOON AND EARLY EVENING. THIS MORNING A MID LEVEL CIG ARRIVING, SOME RAIN POSSIBLE LATE AT KABE AND KRDG. SOUTH TO SOUTH WEST WINDS AVERAGING 5 TO 10 KNOTS. THIS AFTERNOON AT KABE AND KRDG CIGS AND VSBYS LOWERING TO IFR. RAIN MAY MIX WITH OR CHANGE TO SNOW LATE. ESP KABE. TARMAC ACCUMS NOT EXPECTED. LOCAL KPHL AIRPORTS RAIN ARRIVES AND CIGS AND VSBYS LOWERING TO THE BORDER BETWEEN MVFR AND IFR CONDITIONS. KMIV AND KACY SIMILAR EVOLUTION, BUT LATER IN THE AFTERNOON. WINDS WILL BE TRICKY AS IT DEPENDS UPON THE TRACK OF THE LOW. WE ARE EXPECTING IT TO PASS TO THE SOUTH OF ALL THE TERMINALS ACROSS DELMARVA. THERE WILL BE A SLOW BACKING OF THE WINDS FROM SOUTH TO NORTHEAST AS THE AFTERNOON PROGRESSES. SPEEDS SHOULD BE AROUND 10 KNOTS. THIS EVENING, CONDITIONS BOTTOMING EAST OT IFR EARLY AND THEN IMPROVING CONDITIONS THE REST OF THE EVENING. PCPN SHOULD END BY 04Z ALL TERMINALS. WINDS WILL CONTINUE TO BACK TOWARD THE NORTH AND THEN NORTHWEST WITH AVERAGE SPEEDS AROUND 10 KNOTS, BUT SOME GUSTINESS TO AROUND 20 KNOTS FROM THE KPHL AIRPORTS SOUTHEASTWARD. OVERNIGHT IMPROVING CONDITIONS CONTINUING WITH A VFR CIG BECOMING CLEAR AND NORTHWEST WINDS AVERAGING AROUND 10 TO 15 KNOTS. OUTLOOK... WEDNESDAY AND THURSDAY...VFR OVERALL. AN INCREASE IN CLOUDS SHOULD OCCUR LATE THURSDAY AHEAD OF A COLD FRONT WITH SHOWERS LURKING NOT TO FAR TO OUR WEST LATE AT NIGHT. GENERALLY LIGHT WINDS WEDNESDAY DUE TO HIGH PRESSURE IN PLACE, THEN A SOUTHERLY FLOW DEVELOPS WEDNESDAY NIGHT AND THURSDAY WITH SOME GUSTINESS DURING THURSDAY. FRIDAY AND SATURDAY...MVFR TO POTENTIALLY IFR CONDITIONS WITH SHOWERS. A THUNDERSTORM CANNOT BE RULED OUT AHEAD OF A COLD FRONT FRIDAY. POTENTIALLY GUSTY SOUTHWESTERLY WINDS FRIDAY, SHIFTING TO THE NORTHWEST FRIDAY NIGHT INTO SATURDAY. SHOWERS SHOULD END SATURDAY MORNING FOLLOWED BY CONDITIONS RETURNING TO VFR. THERE IS LOWER CONFIDENCE REGARDING THE TIMING OF THE CLEARING SATURDAY. && .MARINE... RIGHT NOW CONDITIONS ARE BELOW SCA CRITERIA ON THE OCEAN. HOWEVER BOTH SEAS AND GUSTS ARE EXPECTED TO INCREASE SOME THIS AFTERNOON. WE WILL KEEP THE SCA UP FOR THE POTENTIAL OF WIND GUSTS AROUND 25 KNOTS THIS AFTERNOON AND LOCALIZED SEAS NEAR FIVE FEET. THE ADVISORY IS NOT IN EFFECT FOR DELAWARE BAY, ALTHOUGH THERE COULD BE A FEW GUSTS TO 25 KNOTS THIS MORNING AND AGAIN LATER TONIGHT WITH THE DOWN THE BAY FLOW. WE WILL REACCESS THE BAY LATER TODAY. OUTLOOK... WEDNESDAY...HIGH PRESSURE BUILDS OVER THE AREA BUT THEN BEGINS TO SHIFT OFFSHORE AT NIGHT. AS A RESULT, THE WINDS AND SEAS WILL DECREASE AND BE BELOW ADVISORY CRITERIA. THURSDAY AND FRIDAY...A SOUTH TO SOUTHWEST FLOW WILL INCREASE AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF A COLD FRONT. A MUCH WARMER AIRMASS HOWEVER WILL BE MOVING OVER THE COLDER WATERS, AND THIS WILL LIMIT THE MIXING. AS A RESULT, THE HIGHEST GUSTS WILL PROBABLY BE CLOSER TO THE COAST. THE INCREASING SOUTHERLY FLOW WILL BUILD THE SEAS AND THEREFORE A SMALL CRAFT ADVISORY LOOKS TO BE NEEDED. THE WAVEWATCH GUIDANCE IS PROBABLY OVERDONE SOME WITH THE SEAS AS THE GFS IS A BIT TO STRONG WITH THE SURFACE WINDS, THEREFORE WE STAYED CLOSER TO CONTINUITY WHICH HAD THIS FACTORED IN. SATURDAY...A COLD FRONT SHOULD BE EAST OF OUR AREA WITH A WIND SHIFT TO THE NORTHWEST, AND THE WINDS COULD BE A BIT GUSTY AS SOME COOLING TAKES PLACE. THE SEAS SHOULD BE AT OR ABOVE 5 FEET ON THE OCEAN, BUT TENDING TO SUBSIDE WITH THE OFFSHORE FLOW. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR PAZ054-055. NJ...WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR NJZ001. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455. && $$ SYNOPSIS...GORSE NEAR TERM...GAINES/GIGI SHORT TERM...GIGI LONG TERM...GORSE AVIATION...GIGI/GORSE MARINE...GIGI/GORSE/GAINES
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
804 AM EDT TUE MAR 31 2015 .SYNOPSIS... LOW PRESSURE WILL QUICKLY TRACK SOUTHEASTWARD FROM THE GREAT LAKES REGION, CROSSING OUR AREA LATER TODAY INTO THIS EVENING. HIGH PRESSURE WILL THEN BUILD INTO OUR REGION WEDNESDAY BEFORE QUICKLY SHIFTING OFFSHORE WEDNESDAY NIGHT INTO THURSDAY. THE NEXT COLD FRONT IS SCHEDULED TO ARRIVE LATE FRIDAY, WITH A SECONDARY COLD FRONT MOVING THROUGH LATE SATURDAY NIGHT AND SUNDAY MORNING. A HIGH PRESSURE SYSTEM IS THEN NEARBY FOR MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 8:00 AM: FORECAST STILL LOOKS ON TRACK FOR A LIGHT ACCUMULATING SNOWFALL IN THE HIGHER TERRAIN OF SUSSEX NJ AND THE POCONOS TODAY WITH A PERIOD OF RAIN OR RAIN/SNOW MIX ELSEWHERE. SLOWED THE INCREASE OF CLOUDS SOMEWHAT OVER THE NEXT FEW HOURS THOUGH. THE PRECIPITATION ONSET TIME MAY NEED TO BE PUSHED BACK BY 1-2 HOURS AS WELL BASED ON THE LATEST RAP AND HRRR RUNS. ATTM DID NOT MAKE THIS ADJUSTMENT WITH THE POSSIBILITY STILL PRESENT OF RAIN/ MIX ENTERING THE WESTERN FRINGE OF THE CWA BY 16-17Z. IN THE POCONOS AND NW NJ, THE PRECIPITATION MAY START AS A MIX BEFORE CHANGING TO SNOW WITH EVAPORATIVE COOLING OCCURRING. PREVIOUS: THE GFS INITIALIZATION LOOKED A LITTLE WEAK WITH THE APPROACHING TROF AND MAYBE WHY ITS TIMING IS THE FASTEST. ITS SLIGHTLY WARMER AT 925MB UPSTREAM THAN THE MODELS THINK. OVERALL THE MODELS ARE MUCH CLOSER THAN THEY WERE YESTERDAY, BUT THERE REMAINS DIFFERENCES AS TO THE NORTHERN EXTENT OF HEAVIER PCPN. THEY HAVE TRENDED COLDER AND OVERALL WETTER. MODEL PREDICTED PWATS HOWEVER ARE AROUND HALF AN INCH AND GIVEN THIS IS ABOUT A 6 TO 12 HR EVENT, BELIEVE QPF ABOVE HALF AN INCH ARE TOO ROBUST UNLESS A FGEN BAND CONCENTRATES IN A NARROW AREA FOR A PROTRACTED PERIOD. OUR FORECAST SOLUTION IS CLOSEST TO A COMBINATION OF THE UKMET`S QPF FIELD, GFS PATH (COUPLE OF HOURS SLOWER) AND WRF-NMM`S BETTER LLVL THERMALS AND SFC TEMPS FOR THE NORTHERN SNOWIER AREAS. WINTER WEATHER ADVISORY FOR OUR THREE NORTHERN COUNTIES. IF THIS WAS NIGHTTIME THIS WOULD BE MORE OF A CONFIDENT SNOWFALL FCST, BUT GIVEN THIS IS A TIMING REPEAT OF MARCH 20TH, THERE REMAINS UNCERTAINTY AS TO HOW MUCH SNOW CAN ACCUMULATE. MARCH 20TH SHOWED INTENSITY CAN TRUMP THE LATE MARCH SUN. THE HOURLY RATES AT PEAK TIME DURING THIS AFTERNOON IS NEARING .1 WATER EQUIVALENT PER HOUR. THIS SHOULD BE ENOUGH TO START ACCUMULATING. BUT THIS OVERALL WINDOW IS SMALLER THAN THAT PREVIOUS EVENT. ALSO THE INITIAL BOUNDARY LAYER CAN WARM THIS MORNING AND THIS WILL PROLONG THE CHANGE TO SNOW AT LOWER TERRAIN LOCATIONS. THE HIGHER TERRAIN OF THE POCONOS AND WESTERN SUSSEX COUNTY NJ IT WILL BE PRETTY MUCH COLD ENOUGH FOR SNOW. THE UNCERTAINTY IS TO WILL THE HEAVIER PCPN REACH THAT FAR NORTH. THE GENERAL CONSENSUS IS YES, BUT THERE IS NOT UNIFORMITY. THE GFS DIAGS DO SHOW FGEN BANDING IN THAT AREA, BUT THE EXIT REGION OF THE 250MB JET AND BEST MID LEVEL QVEC CONVERGENCE IS A BIT FTHR TO THE SOUTH. THERE WILL BE A 45 KT LLJ FEEDING ACROSS THIS BOUNDARY AND THERE IS A BROAD 200MB OF LIFT PREDICTED AT 290K ACROSS OUR CWA THIS AFTERNOON. HERE GOES, PCPN MOVES IN NORTH LATE THIS MORNING AND EARLY THIS AFTERNOON AND LATER IN THE AFTERNOON THE REST OF OUR CWA. THE SOUNDINGS ARE DRY ABOVE THE SFC AND EVAP COOLING SHOULD CHANGE ANY BRIEF START OF RAIN IN THE HIGHER TERRAIN OF THE POCONOS TO SNOW. ELSEWHERE ITS THE LESS EFFICIENT DYNAMIC COOLING THAT IS EXPECTED TO DO THE TRICK. OBVIOUSLY ELEVATION HELPS AS THE GFS PREDICTED FREEZING LEVEL AT ABE DROPPING TO 800 FEET SHOWS. ALL THE MODELS LOWER SFC TEMPS AND WBZS TO AROUND FREEZING IN THE POCONOS, BUT STRUGGLE ELSEWHERE. SO THERE IS GREATER UNCERTAINTY FARTHER EAST IN SUSSEX COUNTY NJ. THE NEXT TIER SOUTHWARD, THERE COULD BE SOME HIGHER TERRAIN LOCATIONS THAT DO GET A COUPLE OF INCHES, NOT AS WIDESPREAD AS THE ADVISORY AREA WE BELIEVE. WE WILL HAVE TO WATCH IF THE FGEN BANDING ESTABLISHES ITSELF IN THIS LOCATION LATER TODAY, BUT CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE AN ADVISORY. WE WILL KEEP MENTION IN THE HWO. TEMPERATURES ARE ALSO PROBLEMATICAL AS THE GFS LOWER TEMPS ARE BANKING ON A FASTER PCPN ARRIVAL TIME. GIVE ITS ARRIVAL UNTIL THE AFTERNOON AND NAM MOS MAY BE RIGHT FOR THE WRONG REASON. WE COMPROMISED BETWEEN THE DATASETS. 06Z MODELS PRETTY MUCH HELD THEIR OWN. E.G. ABE FREEZING LEVEL LATE THIS AFTERNOON AT 800 TO 900 FEET. 06Z MODEL QPF VERIFICATION GEOGRAPHICALLY WAS GOOD WITH THE GFS AND NAM A BIT WET. GFS ENSEMBLE MEAN WAS SLIGHTLY SLOWER THAN THE OP. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... OPTING FOR THE SLOWER MODEL TIMING, WE CARRIED PCPN INTO THIS EVENING, ESPECIALLY IN NJ. EVENT SHOULD BE DONE BY ABOUT MIDNIGHT. THE PREDICTED VORT MAX OVERNIGHT BECOMES QUITE CHANNELIZED AND MODELS PREDICTED MOISTURE OVERALL MEAGER. WE CLEARED SKIES OVERNIGHT. WE OPTED FOR A STAT GUIDANCE COMPROMISE FOR MINS. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE OVERALL SYNOPTIC SETUP IS AN ACTIVE ONE BUT ALSO COMPRISED OF A FAST FLOW REGIME. AN UPPER-LEVEL TROUGH ACROSS THE NORTHEAST TO START WEDNESDAY WILL SHIFT EAST WITH A RIDGE BUILDING IN THURSDAY AS SHORT WAVE ENERGY MOVES ACROSS THE MIDWEST. THIS SHORT WAVE ENERGY WILL HELP TO AMPLIFY AN UPPER-LEVEL TROUGH ACROSS THE GREAT LAKES AND OHIO VALLEY LATE FRIDAY, THEN INTO THE EAST SATURDAY. IT APPEARS THIS TROUGH REMAINS THROUGH MONDAY, ALTHOUGH IT SHOULD START TO RETREAT NORTHWARD WITH TIME. WE USED A MODEL BLEND FOR WEDNESDAY THROUGH FRIDAY, THEN INCORPORATED THE 00Z WPC GUIDANCE IN WITH CONTINUITY THEREAFTER. SOME ADJUSTMENTS WERE THEN MADE FOLLOWING ADDITIONAL COLLABORATION WITH OUR NEIGHBORING OFFICES. FOR WEDNESDAY AND THURSDAY...AN UPPER-LEVEL TROUGH AXIS IS FORECAST TO PIVOT ACROSS THE AREA WEDNESDAY. A SHORT WAVE ROUNDING THE BASE OF THIS TROUGH MAY HAVE SOME SHOWERS WITH IT TO OUR NORTHWEST, HOWEVER IT MAY END UP DAMPENING OUT AS IT TRACKS SOUTHEAST AND EAST. THEREFORE, WE WILL CONTINUE WITH A DRY FORECAST. SOME CAA AT LEAST DURING THE FIRST HALF OF THE DAY WILL RESULT IN A COOLER DAY. HIGH PRESSURE SHIFTS OFFSHORE WEDNESDAY NIGHT INTO THURSDAY ALLOWING FOR A RETURN FLOW. AS THIS OCCURS, WAA WILL INCREASE AHEAD OF OUR NEXT SYSTEM. THIS WILL BE IN THE FORM OF A COLD FRONT THAT WILL BE APPROACHING LATE THURSDAY NIGHT. AHEAD OF THIS, A NOTABLE INCREASE IN AFTERNOON TEMPERATURES ARE EXPECTED THURSDAY /ALTHOUGH PROBABLY COOLER ALONG THE COAST DUE TO A SOUTHERLY FLOW OFF THE COLDER OCEAN/. IT APPEARS THAT A LEAD SHORT WAVE GENERATES SOME SHOWERS WELL OUT AHEAD OF THE COLD FRONT THURSDAY AND THESE MAY START TO MOVE INTO OUR WESTERN ZONES LATER THURSDAY NIGHT. IT APPEARS THAT IT WILL TAKE AWHILE FARTHER EAST THEREFORE WE SLOWED DOWN THE POP INCREASE AT NIGHT FROM WEST TO EAST. IN ADDITION, THE FORECAST SOUNDINGS GENERALLY SHOW A DEEPENING MOIST PROFILE AS A LOW-LEVEL JET INCREASES THE THETA-E ADVECTION. THIS RESULTS IN A DECREASE IN THE SHOWALTER VALUES, HOWEVER NO REAL INSTABILITY LOOKS TO BE PRESENT. AS A RESULT THERE IS A QUESTION WHETHER OR NOT CHARGE SEPARATION CAN TAKE PLACE AND THEREFORE WE REMOVED THE SLIGHT CHC OF THUNDER ATTM. AS MIXING INCREASES THURSDAY, A BREEZY AFTERNOON SHOULD RESULT. FOR FRIDAY AND SATURDAY...A COLD FRONT WILL GRADUALLY SETTLE SOUTHEAST ACROSS OUR AREA LATER FRIDAY INTO SATURDAY. A WARM SOUTHWESTERLY FLOW WILL BE IN PLACE AND THIS COMBINED WITH LARGE SCALE LIFT FROM THE INCOMING COLD FRONT, UPPER-LEVEL TROUGH AND AN UPPER-LEVEL JET SHOULD RESULT IN SHOWERS OR EVEN BANDS OF SHOWERS. IF ENOUGH INSTABILITY CAN BE REALIZED, SOME THUNDER COULD OCCUR ON FRIDAY AHEAD OF THE COLD FRONT. WE WILL MAINTAIN CONTINUITY AND INCLUDE A SLIGHT CHC OF THUNDER IN THE FORECAST DATABASE. LOW PRESSURE SHOULD BE TRACKING TO OUR NORTH AND NORTHEAST FRIDAY NIGHT, PULLING THE COLD FRONT TO OUR EAST EARLY SATURDAY. AS SOME ENERGY ROTATES AROUND THE BASE OF THE TROUGH, A COUPLE OF WAVES OF LOW PRESSURE SHOULD DEVELOP ALONG THE COLD FRONT. THE FIRST ONE SHOULD DELAY THE COLD FRONTAL PASSAGE ACROSS OUR AREA AND THEN THE SECOND ONE TRACKS WELL TO OUR SOUTH AND EAST AFTER THE FRONT CLEARS OUR AREA EARLY SATURDAY. THE TIMING AND POSITIONING OF THE COLD FRONT FRIDAY WILL IMPACT TEMPERATURES, HOWEVER OUR ENTIRE CWA SHOULD REMAIN IN THE WARM SECTOR. WE THEN KEPT LOW CHC POPS FOR SHOWERS IN FOR SATURDAY THEN DRYING OVERTAKES THE AREA. A SECONDARY COLD FRONT LOOKS TO DROP INTO THE AREA LATE SATURDAY NIGHT. FOR SUNDAY AND MONDAY...A COLD FRONT SHOULD MOVE ACROSS THE AREA SUNDAY MORNING, HOWEVER THIS LOOKS MOISTURE STARVED. HIGH PRESSURE THEN SLIDES TO OUR EAST LATE SUNDAY INTO MONDAY, ALTHOUGH THE TAILEND OF THE AFOREMENTIONED COLD FRONT MAY REMAIN FROM THE OHIO VALLEY WESTWARD TO THE NORTHERN PLAINS. FOR NOW, KEPT THIS TIMEFRAME DRY WITH MODERATION IN TEMPERATURES ON MONDAY. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY, AND SURROUNDING AREAS. THE 12Z TAFS STILL BRING ALL OF OUR SITES TO LOW MVFR OR IFR CONDITIONS THIS AFTERNOON WITH A HIGH DEGREE OF UNCERTAINTY ABOUT THE WIND DIRECTIONS THIS AFTERNOON AND EARLY EVENING. THIS MORNING A MID LEVEL CIG ARRIVING, SOME RAIN POSSIBLE LATE AT KABE AND KRDG. SOUTH TO SOUTH WEST WINDS AVERAGING 5 TO 10 KNOTS. THIS AFTERNOON AT KABE AND KRDG CIGS AND VSBYS LOWERING TO IFR. RAIN MAY MIX WITH OR CHANGE TO SNOW LATE. ESP KABE. TARMAC ACCUMS NOT EXPECTED. LOCAL KPHL AIRPORTS RAIN ARRIVES AND CIGS AND VSBYS LOWERING TO THE BORDER BETWEEN MVFR AND IFR CONDITIONS. KMIV AND KACY SIMILAR EVOLUTION, BUT LATER IN THE AFTERNOON. WINDS WILL BE TRICKY AS IT DEPENDS UPON THE TRACK OF THE LOW. WE ARE EXPECTING IT TO PASS TO THE SOUTH OF ALL THE TERMINALS ACROSS DELMARVA. THERE WILL BE A SLOW BACKING OF THE WINDS FROM SOUTH TO NORTHEAST AS THE AFTERNOON PROGRESSES. SPEEDS SHOULD BE AROUND 10 KNOTS. THIS EVENING, CONDITIONS BOTTOMING EAST OT IFR EARLY AND THEN IMPROVING CONDITIONS THE REST OF THE EVENING. PCPN SHOULD END BY 04Z ALL TERMINALS. WINDS WILL CONTINUE TO BACK TOWARD THE NORTH AND THEN NORTHWEST WITH AVERAGE SPEEDS AROUND 10 KNOTS, BUT SOME GUSTINESS TO AROUND 20 KNOTS FROM THE KPHL AIRPORTS SOUTHEASTWARD. OVERNIGHT IMPROVING CONDITIONS CONTINUING WITH A VFR CIG BECOMING CLEAR AND NORTHWEST WINDS AVERAGING AROUND 10 TO 15 KNOTS. OUTLOOK... WEDNESDAY AND THURSDAY...VFR OVERALL. AN INCREASE IN CLOUDS SHOULD OCCUR LATE THURSDAY AHEAD OF A COLD FRONT WITH SHOWERS LURKING NOT TO FAR TO OUR WEST LATE AT NIGHT. GENERALLY LIGHT WINDS WEDNESDAY DUE TO HIGH PRESSURE IN PLACE, THEN A SOUTHERLY FLOW DEVELOPS WEDNESDAY NIGHT AND THURSDAY WITH SOME GUSTINESS DURING THURSDAY. FRIDAY AND SATURDAY...MVFR TO POTENTIALLY IFR CONDITIONS WITH SHOWERS. A THUNDERSTORM CANNOT BE RULED OUT AHEAD OF A COLD FRONT FRIDAY. POTENTIALLY GUSTY SOUTHWESTERLY WINDS FRIDAY, SHIFTING TO THE NORTHWEST FRIDAY NIGHT INTO SATURDAY. SHOWERS SHOULD END SATURDAY MORNING FOLLOWED BY CONDITIONS RETURNING TO VFR. THERE IS LOWER CONFIDENCE REGARDING THE TIMING OF THE CLEARING SATURDAY. && .MARINE... WE STARTED THE SCA FOR THE OCEAN FROM THE GET GO WITH THIS PACKAGE. SOME SEAS ARE STILL CLOSE TO 5 FEET ON THE OCEAN WATERS. IT IS A BIT DISJOINTED. THE GRADIENT IS CURRENTLY WEAK, BUT IS PREDICTED TO INCREASE TODAY AS THE LOW PRESSURE SYSTEM APPROACHES. THEN WINDS SHOULD RELAX FOR A PERIOD THIS AFTERNOON AS THE AIR TEMPS RISE OVER THE WATERS, BUT SWELLS FROM THE MORNING WINDS SHOULD REACH CRITERIA. THEN THERE SHOULD BE A SCA LEVEL NORTHWEST WIND SURGE TONIGHT AS THE CLIPPER EXITS. THE ADVISORY IS NOT IN EFFECT FOR DELAWARE BAY, ALTHOUGH THERE COULD BE A FEW GUSTS TO 25 KNOTS THIS MORNING AND AGAIN LATER TONIGHT WITH THE DOWN THE BAY FLOW. WE WILL REACCESS THE BAY LATER TODAY. OUTLOOK... WEDNESDAY...HIGH PRESSURE BUILDS OVER THE AREA BUT THEN BEGINS TO SHIFT OFFSHORE AT NIGHT. AS A RESULT, THE WINDS AND SEAS WILL DECREASE AND BE BELOW ADVISORY CRITERIA. THURSDAY AND FRIDAY...A SOUTH TO SOUTHWEST FLOW WILL INCREASE AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF A COLD FRONT. A MUCH WARMER AIRMASS HOWEVER WILL BE MOVING OVER THE COLDER WATERS, AND THIS WILL LIMIT THE MIXING. AS A RESULT, THE HIGHEST GUSTS WILL PROBABLY BE CLOSER TO THE COAST. THE INCREASING SOUTHERLY FLOW WILL BUILD THE SEAS AND THEREFORE A SMALL CRAFT ADVISORY LOOKS TO BE NEEDED. THE WAVEWATCH GUIDANCE IS PROBABLY OVERDONE SOME WITH THE SEAS AS THE GFS IS A BIT TO STRONG WITH THE SURFACE WINDS, THEREFORE WE STAYED CLOSER TO CONTINUITY WHICH HAD THIS FACTORED IN. SATURDAY...A COLD FRONT SHOULD BE EAST OF OUR AREA WITH A WIND SHIFT TO THE NORTHWEST, AND THE WINDS COULD BE A BIT GUSTY AS SOME COOLING TAKES PLACE. THE SEAS SHOULD BE AT OR ABOVE 5 FEET ON THE OCEAN, BUT TENDING TO SUBSIDE WITH THE OFFSHORE FLOW. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY FROM NOON TODAY TO 10 PM EDT THIS EVENING FOR PAZ054-055. NJ...WINTER WEATHER ADVISORY FROM NOON TODAY TO 10 PM EDT THIS EVENING FOR NJZ001. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455. && $$ SYNOPSIS...GORSE NEAR TERM...GAINES/GIGI SHORT TERM...GIGI LONG TERM...GORSE AVIATION...GIGI/GORSE MARINE...GIGI/GORSE
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
854 PM EDT WED APR 1 2015 .UPDATE...OUTFLOW BOUNDARY FROM EARLIER CONVECTION ALONG THE EAST COAST HAS MERGED WITH WEST COAST SEABREEZE SETTING OFF A FEW SHOWERS OVER CLAY/PUTNAM COUNTIES. EXPECT THIS CONVECTION TO BE SHORT LIVED DUE TO WEAKENING INSTABILITY WITH HRRR MODEL SHOWING ACTIVITY ENDING BY 04Z. LOW TEMPERATURES TONIGHT WILL RANGE FROM THE UPPER 50S NORTH TO THE LOWER 60S SOUTH. && .AVIATION...EXPECT VFR CONDITIONS TO PREVAIL TONIGHT. PATCHY FOG LATE TONIGHT MAY RESULT IN MVFR VSBYS WITH POSSIBLE IFR CIGS AT GNV MAINLY 08Z-12Z. EXPECT VFR ON THURSDAY. && .MARINE...ONSHORE WINDS WILL GRADUALLY INCREASE TONIGHT AS HIGH PRESSURE BUILDS TO THE NORTH AND PRESSURE GRADIENT TIGHTENS. EAST WINDS WILL REACH 15 KNOTS WITH SEAS BUILDING UP TO 5 FEET OFFSHORE. RIP CURRENTS: LOW RISK. && .PRELIMINARY POINT TEMPS/POPS... AMG 59 80 61 84 / 0 20 20 10 SSI 60 72 63 78 / 0 10 10 10 JAX 60 78 62 84 / 0 20 10 10 SGJ 63 75 63 80 / 10 10 10 0 GNV 60 82 61 84 / 0 20 20 0 OCF 60 83 61 84 / 0 20 20 0 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ ZIBURA/SHULER/GUILLET
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
637 PM EDT TUE MAR 31 2015 .SYNOPSIS... A COLD FRONT WILL SHIFT SOUTH INTO THE AREA TONIGHT AND WEDNESDAY MORNING WHILE HIGH PRESSURE BUILDS FROM THE NORTH. THE HIGH WILL QUICKLY MOVE OFF THE EASTERN SEABOARD BY THURSDAY. A STRONGER COLD FRONT WILL CROSS THE REGION LATE FRIDAY NIGHT OR SATURDAY...FOLLOWED BY COOLER HIGH PRESSURE THROUGH EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 31/21Z RADAR AND SURFACE MESOANALYSIS SHOWED A PLETHORA OF MESOSCALE BOUNDARIES POSITIONED ACROSS GEORGIA... INCLUDING THE REMNANTS OF A WELL-DEFINED DIFFERENTIAL HEATING BOUNDARY LOCATED JUST SOUTH OF THE I-16/I-75 INTERCHANGE. HIGH RESOLUTION MODELS CONTINUE TO SUGGEST AN UPTICK IN TSTM COVERAGE WILL OCCUR ACROSS CENTRAL GEORGIA AS FORCING ASSOCIATED WITH A PRONOUNCED MID-LEVEL SHORTWAVE MOVING ACROSS ALABAMA INTERACTS WITH A MODERATELY UNSTABLE ATMOSPHERE...BUT IT REMAINS TO BE SEEN EXACTLY HOW MUCH UPSCALE GROWTH WILL OCCUR THIS EVENING... ESPECIALLY AS THE BOUNDARY LAYER BEGINS TO COOL. THE H3R DEPICTS AN ORGANIZED BOW ECHO/QLCS FEATURE MOVING ALONG THE ALTAMAHA RIVER BY MID-EVENING WHILE THE LATEST RAP IS A BIT LESS AGGRESSIVE. EITHER WAY...THERE WILL BE ENOUGH SURFACE BASED INSTABILITY AND 0-6KM BULK SHEAR TO SUPPORT ISOLATED STRONG TO SEVERE TSTMS... MAINLY SOUTH OF THE I-16 CORRIDOR. CONVECTIVE TRENDS ARE BEING MONITORED... ALL GRIDDED AND TEXT FORECASTS HAVE BEEN UPDATED TO REORIENT THE POP SCHEME THROUGH THIS EVENING...MAINLY TO TAKE SHORT TERM TRENDS INTO ACCOUNT. POPS UP TO 40 PERCENT WERE MAINTAINED...ROUGHLY FROM METTER-HINESVILLE AND POINTS SOUTH. ALSO INCREASED THE PROBABILITIES FOR TSTMS FROM SLIGHT CHANCE TO CHANCE. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... WEDNESDAY...THE BACK DOOR COLD FRONT WILL SLOWLY SLIDE SOUTH OF THE AREA...THOUGH IT WILL BE SLOW TO CLEAR OUR FAR SOUTHEAST GA ZONES BEFORE MID AFTERNOON. PRIOR TO THAT...MODERATE SURFACE HEATING AND DEWPOINTS IN THE UPPER 50S TO AROUND 60 MAY ALLOW FOR ISOLATED SHOWERS IN THE MORNING OR PERHAPS A THUNDERSTORM IN THE EARLY AFTERNOON BEFORE DRIER AIR SHIFTS IN FROM THE NORTH. MOST AREAS WILL REMAIN DRY WITH DECREASING CLOUDINESS AND ONLY WEAK LATE-DAY COLD AIR ADVECTION. THUS HIGHS WILL BE IN THE MIDDLE 70S ACROSS SOUTHERN SC AND UPPER 70S TO AROUND 80 IN SOUTHEAST GA. WEDNESDAY NIGHT WILL BE COOLER ACROSS SOUTHERN SC WHERE MOSTLY CLEAR SKIES AND DIMINISHING WINDS WILL OCCUR. ELSEWHERE...INCREASING STRATOCUMULUS LATE NIGHT WITH DEVELOPING ONSHORE FLOW WILL KEEP TEMPS A FEW DEGREES WARMER. ON THURSDAY THE UPPER RIDGE WILL SHIFT OFFSHORE AND THE SURFACE HIGH WILL MOVE INTO THE WESTERN ATLANTIC. LOW LEVEL FLOW BECOMES ONSHORE AND SURFACE DEWPOINTS INCREASE INTO THE LOWER 60S ACROSS SOUTHEAST GA. MEANWHILE ALOFT A SHORTWAVE WILL MOVE IN DURING THE AFTERNOON HOURS...POTENTIALLY TRIGGERING ISOLATED SHOWERS AND TSTMS LATE IN THE DAY ACROSS WESTERN ZONES. HIGHS WILL BE IN THE UPPER 70S EXCEPT NEAR THE COAST WHERE A ROBUST SEA BREEZE WILL KEEP TEMPS IN THE UPPER 60S. FRIDAY...AHEAD OF AN APPROACHING COLD FRONT...THERMAL RIDGING/ COMPRESSIONAL HEATING SHOULD PUSH TEMPERATURES INTO THE MID 80S. AN ISOLATED SHOWER/THUNDERSTORM CANNOT BE RULED OUT IF/WHERE LOW LEVEL CONVERGENCE DEVELOPS EAST OF I-95...BUT THE POTENTIAL FOR CONVECTION APPEARS TOO LOW TO JUSTIFY A MENTION WITHIN PUBLIC FORECASTS. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A COLD FRONT WILL PUSH INTO THE REGION EITHER LATE FRIDAY NIGHT OR DURING THE DAY SATURDAY. 31/00 UTC GUIDANCE TIMING DIFFERENCES PERSIST...RANGING FROM A FAST OPERATIONAL GFS WHICH PUSHES THE FRONT COMPLETELY THROUGH THE REGION EARLY SATURDAY WITH LIMITED CHANCE FOR CONVECTION TO A SOMEWHAT SLOWER OPERATIONAL EURO WHICH DEPICTS THE FRONT BISECTING THE FORECAST AREA EARLY SATURDAY AFTERNOON... SUPPORTING A GREATER CHANCE FOR SHOWERS/THUNDERSTORMS AND PERHAPS EVEN A POTENTIAL FOR SOME SEVERE WEATHER ESPECIALLY SOUTH/EAST. MAINTAINED SLIGHT CHANCE/CHANCE POPS FOR SHOWERS/THUNDERSTORMS LATE FRIDAY NIGHT INTO SATURDAY...BUT FURTHER ADJUSTMENTS COULD BE NEEDED WITHIN SUBSEQUENT FORECASTS. IN ANY CASE...POST FROPA HIGH PRESSURE WILL PROVIDE SLIGHTLY COOLER THAN NORMAL TEMPERATURES BY SATURDAY NIGHT/SUNDAY...FOLLOWED BY A WARMING TREND AS HIGH PRESSURE SHIFTS OFFSHORE EARLY NEXT WEEK. ALSO...INTRODUCED SLIGHT CHANCE/CHANCE POPS EARLY NEXT WEEK AS MEDIUM RANGE GUIDANCE DEPICTS INCREASING MOISTURE SPREADING INTO THE REGION FROM THE WEST. HOWEVER...MODEL AGREEMENT REGARDING FORECAST DETAILS OF ANY PRECIPITATION REMAINS POOR EARLY NEXT WEEK. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... VFR. WATCHING UPSTREAM TSTM ACTIVITY...WHICH MAY MAKE A RUN FOR KSAV 02-06Z. RIGHT NOW IT APPEARS ACTIVITY THAT HOLDS TOGETHER WILL LIKELY REMAIN SOUTH OF THE TERMINAL. WILL NOT INCLUDE A MENTION OF TSRA JUST YET...BUT THIS WILL BE WATCHED CAREFULLY. WIND SHIFT WILL A BACKDOOR FRONT WILL MOVE THROUGH KCHS ROUGHLY 14Z...BUT WASHOUT BEFORE REACHING KSAV AND GETTING ENTANGLED WITH THE DEVELOPING ONSHORE FLOW. EXTENDED AVIATION OUTLOOK...ISOLATED SHOWERS AND TSTMS COULD AFFECT EITHER TERMINAL LATE THURSDAY AND SCATTERED SHOWERS AND TSTMS EXPECTED SATURDAY. OTHERWISE...MAINLY VFR. && .MARINE... THIS EVENING AND TONIGHT...HIGH PRESSURE WILL PREVAIL OVER THE COASTAL WATERS EARLY...BUT THE PRESSURE GRADIENT WILL BECOME MORE ENHANCED THIS EVENING INTO EARLY TONIGHT AS A COLD FRONT ADVANCES CLOSER TO THE AREA. A BRIEF PERIOD OF SMALL CRAFT ADVISORY LEVEL WINDS COULD OCCUR IN NORTHERN SC WATERS AND OFFSHORE GEORGIA WATERS AS THE FROPA OCCURS...BUT CONDITIONS SHOULD FALL JUST SHORT OF CRITERIA. HAVE MAINTAINED A CAP OF 15 KT WINDS IN THE CHARLESTON HARBOR AND 20 KT WINDS OFF THE CHARLESTON COUNTY COAST AND OFFSHORE GEORGIA WATERS. SOUTHWEST WINDS SHOULD ALSO BECOME NORTHWEST BEHIND THE FRONT LATE. ISOLATED THUNDERSTORMS COULD IMPACT THE GEORGIA WATERS TONIGHT. A FEW THUNDERSTORMS COULD BE STRONG WITH GUSTY WINDS AND FREQUENT LIGHTNING STRIKES. WINDS WILL BRIEFLY SURGE OUT OF THE NE WEDNESDAY AND WEDNESDAY NIGHT IN WAKE OF A BACK DOOR COLD FRONT BUT WINDS/SEAS EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS. MODERATE ONSHORE FLOW EXPECTED THURSDAY INTO FRIDAY AS THE SURFACE HIGH SHIFTS OFF THE COAST. THE SEA BREEZE WILL BLOW AT 10-15 KT ALONG THE COAST BOTH DAYS. SEAS COULD BUILD TO NEAR SMALL CRAFT ADVISORY LEVELS LATE FRIDAY OR FRIDAY NIGHT ESPECIALLY ACROSS THE CHARLESTON NEARSHORE AND GA OFFSHORE WATERS. IN THE WAKE OF A COLD FRONT...COLD ADVECTION AND BUILDING HIGH PRESSURE WILL PRODUCE A SURGE OF NORTHEAST WINDS AND ELEVATED SEAS DURING THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. SMALL CRAFT ADVISORIES APPEAR LIKELY WITH THIS EVENT. MEANWHILE...HIGHER DEWPOINTS IN THE 60S ADVECTING OVER THE WATERS COULD SUPPORT SOME SEA FOG BEGINNING THURSDAY/THURSDAY NIGHT AND CONTINUING UNTIL COLD FRONTAL PASSAGE OCCURS SATURDAY. PROBABILITIES CURRENTLY TOO LOW TO INCLUDE IN FORECAST. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
509 PM EDT TUE MAR 31 2015 .SYNOPSIS... A COLD FRONT WILL SHIFT SOUTH INTO THE AREA TONIGHT AND WEDNESDAY MORNING WHILE HIGH PRESSURE BUILDS FROM THE NORTH. THE HIGH WILL QUICKLY MOVE OFF THE EASTERN SEABOARD BY THURSDAY. A STRONGER COLD FRONT WILL CROSS THE REGION LATE FRIDAY NIGHT OR SATURDAY...FOLLOWED BY COOLER HIGH PRESSURE THROUGH EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... MESOSCALE UPDATE...31/21Z RADAR AND SURFACE MESOANALYSIS SHOWED A PLETHORA OF MESOSCALE BOUNDARIES POSITIONED ACROSS GEORGIA... INCLUDING THE REMNANTS OF A WELL-DEFINED DIFFERENTIAL HEATING BOUNDARY LOCATED JUST SOUTH OF THE I-16/I-75 INTERCHANGE. HIGH RESOLUTION MODELS CONTINUE TO SUGGEST AN UPTICK IN TSTM COVERAGE WILL OCCUR ACROSS CENTRAL GEORGIA AS FORCING ASSOCIATED WITH A PRONOUNCED MID-LEVEL SHORTWAVE MOVING ACROSS ALABAMA INTERACTS WITH A MODERATELY UNSTABLE ATMOSPHERE...BUT IT REMAINS TO BE SEEN EXACTLY HOW MUCH UPSCALE GROWTH WILL OCCUR THIS EVENING... ESPECIALLY AS THE BOUNDARY LAYER BEGINS TO COOL. THE H3R DEPICTS AN ORGANIZED BOW ECHO/QLCS FEATURE MOVING ALONG THE ALTAMAHA RIVER BY MID-EVENING WHILE THE LATEST RAP IS A BIT LESS AGGRESSIVE. EITHER WAY...THERE WILL BE ENOUGH SURFACE BASED INSTABILITY AND 0-6KM BULK SHEAR TO SUPPORT ISOLATED STRONG TO SEVERE TSTMS... MAINLY SOUTH OF THE I-16 CORRIDOR. CONVECTIVE TRENDS ARE BEING MONITORED... ALL GRIDDED AND TEXT FORECASTS HAVE BEEN UPDATED TO REORIENT THE POP SCHEME THROUGH THIS EVENING...MAINLY TO TAKE SHORT TERM TRENDS INTO ACCOUNT. POPS UP TO 40 PERCENT WERE MAINTAINED...ROUGHLY FROM METTER-HINESVILLE AND POINTS SOUTH. ALSO INCREASED THE PROBABILITIES FOR TSTMS FROM SLIGHT CHANCE TO CHANCE. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... WEDNESDAY...THE BACK DOOR COLD FRONT WILL SLOWLY SLIDE SOUTH OF THE AREA...THOUGH IT WILL BE SLOW TO CLEAR OUR FAR SOUTHEAST GA ZONES BEFORE MID AFTERNOON. PRIOR TO THAT...MODERATE SURFACE HEATING AND DEWPOINTS IN THE UPPER 50S TO AROUND 60 MAY ALLOW FOR ISOLATED SHOWERS IN THE MORNING OR PERHAPS A THUNDERSTORM IN THE EARLY AFTERNOON BEFORE DRIER AIR SHIFTS IN FROM THE NORTH. MOST AREAS WILL REMAIN DRY WITH DECREASING CLOUDINESS AND ONLY WEAK LATE-DAY COLD AIR ADVECTION. THUS HIGHS WILL BE IN THE MIDDLE 70S ACROSS SOUTHERN SC AND UPPER 70S TO AROUND 80 IN SOUTHEAST GA. WEDNESDAY NIGHT WILL BE COOLER ACROSS SOUTHERN SC WHERE MOSTLY CLEAR SKIES AND DIMINISHING WINDS WILL OCCUR. ELSEWHERE...INCREASING STRATOCUMULUS LATE NIGHT WITH DEVELOPING ONSHORE FLOW WILL KEEP TEMPS A FEW DEGREES WARMER. ON THURSDAY THE UPPER RIDGE WILL SHIFT OFFSHORE AND THE SURFACE HIGH WILL MOVE INTO THE WESTERN ATLANTIC. LOW LEVEL FLOW BECOMES ONSHORE AND SURFACE DEWPOINTS INCREASE INTO THE LOWER 60S ACROSS SOUTHEAST GA. MEANWHILE ALOFT A SHORTWAVE WILL MOVE IN DURING THE AFTERNOON HOURS...POTENTIALLY TRIGGERING ISOLATED SHOWERS AND TSTMS LATE IN THE DAY ACROSS WESTERN ZONES. HIGHS WILL BE IN THE UPPER 70S EXCEPT NEAR THE COAST WHERE A ROBUST SEA BREEZE WILL KEEP TEMPS IN THE UPPER 60S. FRIDAY...AHEAD OF AN APPROACHING COLD FRONT...THERMAL RIDGING/ COMPRESSIONAL HEATING SHOULD PUSH TEMPERATURES INTO THE MID 80S. AN ISOLATED SHOWER/THUNDERSTORM CANNOT BE RULED OUT IF/WHERE LOW LEVEL CONVERGENCE DEVELOPS EAST OF I-95...BUT THE POTENTIAL FOR CONVECTION APPEARS TOO LOW TO JUSTIFY A MENTION WITHIN PUBLIC FORECASTS. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A COLD FRONT WILL PUSH INTO THE REGION EITHER LATE FRIDAY NIGHT OR DURING THE DAY SATURDAY. 31/00 UTC GUIDANCE TIMING DIFFERENCES PERSIST...RANGING FROM A FAST OPERATIONAL GFS WHICH PUSHES THE FRONT COMPLETELY THROUGH THE REGION EARLY SATURDAY WITH LIMITED CHANCE FOR CONVECTION TO A SOMEWHAT SLOWER OPERATIONAL EURO WHICH DEPICTS THE FRONT BISECTING THE FORECAST AREA EARLY SATURDAY AFTERNOON... SUPPORTING A GREATER CHANCE FOR SHOWERS/THUNDERSTORMS AND PERHAPS EVEN A POTENTIAL FOR SOME SEVERE WEATHER ESPECIALLY SOUTH/EAST. MAINTAINED SLIGHT CHANCE/CHANCE POPS FOR SHOWERS/THUNDERSTORMS LATE FRIDAY NIGHT INTO SATURDAY...BUT FURTHER ADJUSTMENTS COULD BE NEEDED WITHIN SUBSEQUENT FORECASTS. IN ANY CASE...POST FROPA HIGH PRESSURE WILL PROVIDE SLIGHTLY COOLER THAN NORMAL TEMPERATURES BY SATURDAY NIGHT/SUNDAY...FOLLOWED BY A WARMING TREND AS HIGH PRESSURE SHIFTS OFFSHORE EARLY NEXT WEEK. ALSO...INTRODUCED SLIGHT CHANCE/CHANCE POPS EARLY NEXT WEEK AS MEDIUM RANGE GUIDANCE DEPICTS INCREASING MOISTURE SPREADING INTO THE REGION FROM THE WEST. HOWEVER...MODEL AGREEMENT REGARDING FORECAST DETAILS OF ANY PRECIPITATION REMAINS POOR EARLY NEXT WEEK. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS SHOULD PREVAIL AT BOTH CHS AND SAV TERMINALS THROUGH 18Z WEDNESDAY. HOWEVER...BRIEF MVFR CONDITIONS ARE POSSIBLE AT EITHER TERMINAL TONIGHT AS A COLD FRONT SHIFTS OVER THE AREA. THE SAV TERMINAL COULD ALSO SEE SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS DEVELOP NEAR THE AREA THIS EVENING...BUT CONFIDENCE REMAINS TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. WEST/SOUTHWEST WINDS WILL BE GUSTY INTO THE EVENING AT BOTH TERMINALS...PEAKING AROUND 20 KTS FROM 19-23Z. EXTENDED AVIATION OUTLOOK...ISOLATED SHOWERS AND TSTMS COULD AFFECT EITHER TERMINAL LATE THURSDAY AND SCATTERED SHOWERS AND TSTMS EXPECTED SATURDAY. OTHERWISE...MAINLY VFR. && .MARINE... THIS EVENING AND TONIGHT...HIGH PRESSURE WILL PREVAIL OVER THE COASTAL WATERS EARLY...BUT THE PRESSURE GRADIENT WILL BECOME MORE ENHANCED THIS EVENING INTO EARLY TONIGHT AS A COLD FRONT ADVANCES CLOSER TO THE AREA. A BRIEF PERIOD OF SMALL CRAFT ADVISORY LEVEL WINDS COULD OCCUR IN NORTHERN SC WATERS AND OFFSHORE GEORGIA WATERS AS THE FROPA OCCURS...BUT CONDITIONS SHOULD FALL JUST SHORT OF CRITERIA. HAVE MAINTAINED A CAP OF 15 KT WINDS IN THE CHARLESTON HARBOR AND 20 KT WINDS OFF THE CHARLESTON COUNTY COAST AND OFFSHORE GEORGIA WATERS. SOUTHWEST WINDS SHOULD ALSO BECOME NORTHWEST BEHIND THE FRONT LATE. ISOLATED THUNDERSTORMS COULD IMPACT THE GEORGIA WATERS TONIGHT. A FEW THUNDERSTORMS COULD BE STRONG WITH GUSTY WINDS AND FREQUENT LIGHTNING STRIKES. WINDS WILL BRIEFLY SURGE OUT OF THE NE WEDNESDAY AND WEDNESDAY NIGHT IN WAKE OF A BACK DOOR COLD FRONT BUT WINDS/SEAS EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS. MODERATE ONSHORE FLOW EXPECTED THURSDAY INTO FRIDAY AS THE SURFACE HIGH SHIFTS OFF THE COAST. THE SEA BREEZE WILL BLOW AT 10-15 KT ALONG THE COAST BOTH DAYS. SEAS COULD BUILD TO NEAR SMALL CRAFT ADVISORY LEVELS LATE FRIDAY OR FRIDAY NIGHT ESPECIALLY ACROSS THE CHARLESTON NEARSHORE AND GA OFFSHORE WATERS. IN THE WAKE OF A COLD FRONT...COLD ADVECTION AND BUILDING HIGH PRESSURE WILL PRODUCE A SURGE OF NORTHEAST WINDS AND ELEVATED SEAS DURING THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. SMALL CRAFT ADVISORIES APPEAR LIKELY WITH THIS EVENT. MEANWHILE...HIGHER DEWPOINTS IN THE 60S ADVECTING OVER THE WATERS COULD SUPPORT SOME SEA FOG BEGINNING THURSDAY/THURSDAY NIGHT AND CONTINUING UNTIL COLD FRONTAL PASSAGE OCCURS SATURDAY. PROBABILITIES CURRENTLY TOO LOW TO INCLUDE IN FORECAST. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
104 AM CDT TUE MAR 31 2015 .SHORT TERM... 339 PM CDT TONIGHT THROUGH WEDNESDAY NIGHT... MAIN FOCUS IN THE NEAR TERM IS ON THE CLIPPERY-LIKE SYSTEM CURRENTLY DROPPING SOUTHEAST ACROSS THE UPPER MIDWEST. SURFACE LOW PRESSURE ANALYZED OVER SOUTHWEST MINNESOTA IS PROGGED TO CONTINUE TO MOVE SOUTHEAST OVER NORTHEAST ILLINOIS LATE TONIGHT...THEN MOVE QUICKLY OFF INTO OHIO BY TUESDAY MORNING. AHEAD OF THE LOW...BREEZY WESTERLY WINDS HAVE WARMED TEMPS INTO THE 60S AND EVEN AROUND 70 (STERLING IL) THIS AFTERNOON. AS THE LOW MOVES SOUTHEAST TOWARD THE AREA HOWEVER...WINDS WILL LIKELY BACK TO THE EAST/SOUTHEAST THIS EVENING AND WILL LIKELY CAUSE SOME TEMPERATURE FLUCTUATONS AS FLOW SHIFT FROM OFFSHORE TO ONSHORE ALONG THE ILLINOIS LAKE MICHIGAN SHORE. THUS OUR CURRENT MILD WEATHER WILL LIKELY TURN CHILLIER AT LEAST ALONG THE LAKE LATER THIS EVENING. IN ADDITION...AREA OF LIGHT TO MODERATE RAIN ACROSS WI WILL ALSO SHIFT SOUTHEAST EARLY THIS EVENING... CLIPPING NORTHEAST IL AND NORTHWEST INDIANA INTO TONIGHT. WHILE MUCH OF THE RAIN WILL BE LIGHT...STEEP MID-LEVEL LAPSE RATES NOTED IN RAP SOUNDINGS AND A PERIOD OF DECENT F-GEN FORCING AROUND 850 MB MAY PRODUCE SOME HEAVIER BANDED SHOWERS THIS EVENING. SHOWERS WILL GRADUALLY PULL OFF TO THE EAST AFTER MIDNIGHT AS THE BEST FORCING AND WARM/MOIST ADVECTION SHIFTS AWAY FROM THE CWA WITH THE WAVE. COOLER NORTH-NORTHEAST WINDS ARE IN STORE FOR THE AREA TUESDAY...AS WEAK HIGH PRESSURE RIDGING SPREADS ACROSS THE REGION. WHILE HIGHS IN THE 55-60 RANGE ARE EXPECTED WELL WEST/SOUTHWEST OF THE LAKE... READINGS CLOSER TO THE SHORE WILL LIKELY NOT MAKE IT OUT OF THE MID 40S. THE GOOD NEWS HOWEVER IS THAT THIS COOL DOWN WILL BE BRIEF... AS UPPER RIDGE DEVELOPS ACROSS THE CENTRAL CONUS TUESDAY NIGHT INTO WEDNESDAY...AS A DEEP TROUGH WORKS OUT OF THE NORTHERN ROCKIES AND OUT ACROSS THE CANADIAN PRAIRIES. SURFACE PRESSURE FALLS ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST WILL ALLOW WINDS TO SHIFT SOUTH WEDNESDAY...INCREASING THROUGH WEDNESDAY NIGHT AS THE SURFACE LOW TRACKS NORTH OF THE BORDER. WARMER TEMPS...IN THE UPPER 60S TO LOWER 70S...WILL MAKE FOR A BREEZY MORE SPRING-LIKE DAY. A COLD FRONT TRAILING FROM THE CANADIAN LOW WILL APPROACH THE AREA LATE WEDNESDAY NIGHT...WITH MILD AND MORE HUMID CONDITIONS AHEAD OF THE BOUNDARY. PRECIPITATION CHANCES WILL BE BEST IMMEDIATELY ALONG/AHEAD OF THE FRONT AND MAINLY WEST OF OUR CWA THROUGH THE EVENING...BEFORE INCREASING POTENTIAL FOR SHOWERS/THUNDERSTORMS SPREADS ACROSS NORTHERN IL LATE WEDNESDAY NIGHT. RATZER && .LONG TERM... 339 PM CDT THURSDAY THROUGH MONDAY... SURFACE COLD FRONT CONTINUES TO PUSH SOUTHEAST ACROSS THE FORECAST AREA ON THURSDAY...WITH BEST CHANCE OF SHOWERS AND THUNDERSTORMS FOR MOST OF THE CWA. POTENTIAL FOR SOME STRONG THUNDERSTORMS MAY EVOLVE SOUTH OF THE FRONT (MAINLY OUR SOUTH COUNTIES) DEPENDING UPON CLOUD COVER AND DESTABILIZATION BY AFTERNOON...AS UPPER JET STREAK MOVES OVERHEAD AND SUPPORTS STRONG DEEP LAYER SHEAR IN EXCESS OF 40 KTS. WITH THE FRONT MOVING SLOWLY...TEMPS SHOULD REMAIN FAIRLY MILD...IN THE 60S EXCEPT FOR AREAS NEAR THE LAKE WHERE WINDS MAY SHIFT ONSHORE BEHIND THE FRONT LATER IN THE DAY. THE COLD FRONT CONTINUES TO SAG SOUTH THURSDAY NIGHT INTO FRIDAY...THOUGH GUIDANCE DOES SUPPORT A CONTINUED CHANCE OF PRECIP INTO FRIDAY AS ANOTHER WAVE IS DEPICTED MOVING ALONG THE ELEVATED BAROCLINIC ZONE NORTH OF THE SURFACE FRONT. COOLER AND DRIER WEATHER DOES LOOK TO DEVELOP LATER FRIDAY AND FRIDAY NIGHT AS WEAK HIGH PRESSURE MOVES IN. THE HIGH PRESSURE RIDGE THEN MOVES SOUTH INTO OHIO VALLEY SATURDAY...WITH WINDS SHIFTING WEST AND ALLOWING ANOTHER WARM UP. LONG RANGE SOLUTIONS INDICATE A SHORT WAVE MOVING ACROSS THE NORTHERN LAKES AND TRAILING A COLD FRONT INTO AREA BY SATURDAY EVENING HOWEVER...WITH ANOTHER WEAK HIGH MOVING ACROSS THE AREA SATURDAY NIGHT AS COLD FRONT CONTINUES TO SAG SOUTH. MODELS DIFFER A BIT IN DETAILS BY DAYS 6-7...BUT GENERALLY INDICATE FRONT LIFTING BACK NORTH AS A WARM FRONT SUNDAY AS SURFACE LOW PRESSURE DEVELOPS ACROSS THE PLAINS. PRECIP CHANCES INCREASE DURING THE PERIOD IN THIS SCENARIO...WITH MILDER TEMPERATURES POSSIBLY MUCH WARMER IF MORE AGGRESSIVE GFS PANS OUT WITH WARM FRONT NORTH OF THE AREA. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * WIND DIRECTIONS TODAY...WITH POTENTIAL FOR NORTH-NORTHEAST (350-020 DEG) WINDS EARLY SHIFTING TO NORTHWEST AND THEN POSSIBLE LAKE BREEZE IN THE AFTERNOON ESPECIALLY AT MDW. * POTENTIAL FOR LOWER MVFR/HIGHER END IFR CIGS THIS MORNING. RC //DISCUSSION...UPDATED 06Z... A CLIPPER LOW PRESSURE SYSTEM IS CENTERED OVER SOUTHERN WISCONSIN EARLY THIS MORNING...WITH STRONG PRESSURE FALLS IMMEDIATELY AHEAD OF IT RESULTING IN STRONG SOUTHWEST WINDS GUSTING UP TO 25 TO EVEN 30 KT OVER NORTHEAST ILLINOIS. WINDS WILL SHIFT TO NORTHWEST AND THEN NORTH BEHIND THE LOW AND LAKE INFLUENCE COULD BRING A BRIEF PERIOD OF NORTH-NORTHEAST WINDS TO ORD/MDW BETWEEN ABOUT 12Z AND 14Z. LOW CIGS OVER CENTRAL WISCONSIN MAY ALSO SPREAD SOUTHWARD...AIDED BY THE LAKE INFLUENCE...BUT CONFIDENCE IS LOW...SO HAVE ADDED SCT010 IN ORD/MDW/GYY TAFS FROM 13Z TO 15Z. WIND DIRECTION FORECAST REMAINS TRICKY THROUGH THE DAY TODAY...BUT CURRENT THINKING IS THAT WINDS WILL BACK TO WEST-NORTHWEST EVERYWHERE EXCEPT GYY...WHICH WILL HOLD ONTO NORTHERLY WINDS GIVEN PROXIMITY TO THE LAKE. PRESSURE GRADIENT WILL DIMINISH LATER IN THE AFTERNOON...WITH LAKE BREEZE EXPECTED TO MAKE SOME HEADWAY INLAND...THOUGH IT IS UNCERTAIN HOW FAR. HAVE INDICATED A WIND SHIFT IN THE MDW TAF DURING THE LATE AFTERNOON BUT NOT BROUGHT THE SHIFT TO ORD. LIGHT NORTHEAST WINDS COULD THEN REDEVELOP LATE TONIGHT INTO EARLY WEDNESDAY. RC //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH IN WIND FORECAST THROUGH ABOUT 9Z-10Z TODAY...LOW THEREAFTER. * LOW IN LOW CIG POTENTIAL THIS MORNING. RC //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY...VFR. THURSDAY...SHRA/SOME TSRA LIKELY. PERIODIC IFR POSSIBLE. FRIDAY...CHANCE OF MVFR CIGS. NE WINDS 10KT OR GREATER POSSIBLE. SATURDAY AND SUNDAY...PRIMARILY VFR. IZZI && .MARINE... 134 PM CDT STRONGER WESTERLY WINDS OVER THE LAKE HAVE SINCE DIMINISHED THIS AFTERNOON WITH A WEAK RIDGE OF HIGH PRESSURE OVERHEAD. ALONG WITH THE DIMINISHING TREND THIS AFTERNOON...WINDS HAVE BECOME HIGHLY VARIABLE ACROSS THE ENTIRE THE LAKE. EXPECT EITHER AN ONSHORE COMPONENT OR A PERIOD OF VARIABLE WINDS OVER THE NEARSHORE THIS AFTERNOON INTO THE EVENING...WITH A SOUTH TO EAST WIND OVER THE OPEN WATERS. THIS WILL OCCUR UNTIL LATE IN THE EVENING...WHEN A LOW PRESSURE SYSTEM QUICKLY MOVES SOUTHEAST TO THE SOUTHERN END OF THE LAKE. INCREASING SPEEDS OVER THE ENTIRE LAKE BUT STILL VARIABLE OVER THE SOUTH HALF...WILL THEN TRANSITION TO A NORTHERLY WIND OVER ALL OF THE LAKE BY EARLY TUESDAY MORNING. SPEEDS MAY STILL BE IN THE 15 TO 25 KT RANGE INITIALLY WITH THIS TRANSITION...BUT WILL LIKELY OBSERVE A QUICK DIMINISHING TREND THROUGH MIDDAY. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS WICHITA KS
1241 PM CDT TUE MAR 31 2015 ...UPDATED FOR 18Z AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 357 AM CDT TUE MAR 31 2015 EARLY THIS MORNING A SURFACE TROF EXTENDED FROM THE IA/MO BORDER THRU CENTRAL KS TO THE TX PANHANDLE. MOST TEMPERATURES ACROSS KICT COUNTRY WERE IN THE 45-55 DEGREE RANGE. UNDER MOSTLY CLEAR SKIES. && .UPDATE... ISSUED AT 1040 AM CDT TUE MAR 31 2015 HAVE UPDATED TEMPERATURES ACROSS THE AREA THIS MORNING. AS OF 1040AM THE TEMPERATURE AT EISENHOWER AIRPORT WAS ALREADY 70 DEGREES WHICH WAS SIGNIFICANTLY UNDER FORECAST WHICH WAS ONE OF MANY ACROSS THE FORECAST AREA. THE RAP SEEMED TO HAVE THE BEST HANDLE ON THE CURRENT TRENDS AND USED THAT AS GUIDANCE FOR THE FORECAST THROUGH THE AFTERNOON AND AFTERNOON HIGHS. INCREASED HIGHS TODAY A FEW DEGREES ACROSS THE AREA AND DECREASED DEWPOINTS ACROSS THE AREA. BILLINGS WRIGHT && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 357 AM CDT TUE MAR 31 2015 TODAY & TONIGHT: QUIET WEATHER CONTINUES ACROSS THE NEIGHBORHOOD AS A BROAD UPPER DECK RIDGE SPREADS EAST ACROSS THE NORTHERN AND CENTRAL PLAINS. HAVE KEPT MENTION OF PATCHY FOG IN SOUTHEAST KS FOR EARLY THIS MORNING AS MUCH HIGHER DEWPOINTS IN THE MID & UPPER 50S ARE MIGRATING TOWARD THIS AREA. LATE THIS AFTERNOON...A WEAK SURFACE TROF WILL DEVELOP OVER THE WESTERN PLAINS IN RESPONSE TO A MID- LEVEL SHORTWAVE DEVELOPING OVER THE WESTERN RIO GRANDE & WOULD ALSO INDUCE WARM FRONTOGENESIS ACROSS THE SOUTHERN PLAINS. DESPITE EASTERLY WINDS AROUND 10 MPH SUN-DRENCHED SKIES WILL ENABLE TEMPERATURES TO REACH AROUND 80 IN MOST AREAS. TONIGHT`S TEMPERATURES WILL BE MUCH WARMER AS GULF MOISTURE MIGRATES ACROSS KS. WEDNESDAY & WEDNESDAY NIGHT: THESE PERIODS CONTINUE TO DRAW THE GREATEST ATTENTION. AN UPPER DECK WAVE THAT`LL MOVE EAST ACROSS THE PACIFIC NORTHWEST ON TUESDAY WILL STRENGTHEN AS IT CROSSES THE NORTHERN & CENTRAL ROCKIES TO ALONG THE U.S./CANADIAN BORDER ON WED. THIS CHARACTER WOULD INDUCE THE WESTERN PLAINS SURFACE TROF TO STRENGTHEN WHICH WOULD RESULT IN MUCH WARMER AND INCREASINGLY WINDY WEATHER ACROSS THE NEIGHBORHOOD WEDNESDAY AFTERNOON. DESPITE HIGHER DEWPOINTS CONTINUING TO MIGRATE INTO KS THE STRONG SOUTHERLY WINDS ARE INDICATING THAT AN EXTREME FIRE DANGER IS LIKELY OVER PARTS OF CENTRAL & SOUTH-CENTRAL KS WED AFTERNOON. A FIRE WEATHER WATCH MAY BE REQUIRED FOR WEDNESDAY AFTERNOON. STAY TUNED. THE GREATEST THUNDERSTORM POTENTIAL IS STILL SLATED TO OCCUR WEDNESDAY NIGHT AS THE AFORE-MENTIONED UPPER-DECK WILL SWEEP A COLD FRONT SE INTO A MOIST AND UNSTABLE AIRMASS. MCS DEVELOPMENT IS LIKELY WITH THE MCS SURGING EAST ACROSS PRIMARILY NORTHERN KS & SOUTHERN NEBRASKA. THE RAPID SE-MOVING COLD FRONT DICTATES FINE- TUNING GREATEST CHANCES OF THUNDERSTORMS WITH CENTRAL KS DURING THE EVENING AND EASTERN KS LATER IN THE NIGHT. THURSDAY & THURSDAY NIGHT: THE SE PROGRESS OF THE COLD FRONT WILL HAVE TO BE WATCHED CLOSELY AS IT WILL DECELERATE AS IT VENTURES INTO SE KS & OK. HAVE KEPT HIGHEST POPS ACROSS SE KS WHERE CLOSER TO THE FRONT. POST-FRONTAL SHOWERS ARE POSSIBLE FOR THE REST OF THE NEIGHBORHOOD WHERE MOIST EASTERLY FLOW PREVAILS. .LONG TERM...(FRIDAY THROUGH MONDAY) ISSUED AT 357 AM CDT TUE MAR 31 2015 QUIET WEATHER IS EXPECTED FOR MOST OF THESE PERIODS AS BROAD RIDGE SPREADS EAST ACROSS THE PLAINS. ES && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1241 PM CDT TUE MAR 31 2015 THE MAIN AVIATION FORECAST CONCERN IS THE LOW STRATUS THAT IS EXPECTED EARLY WEDNESDAY MORNING. THE FRONT RETURNS NORTHWARD TONIGHT WITH ABUNDANT MOISTURE. EXPECT LOW STRATUS TO RETURN WITH IT AND FOLLOWING THE LEAD OF THE PREVIOUS FORECAST KEPT AND ADDED LOW STRATUS TO THE FORECAST FOR ALL TERMINALS. DID ADJUST TIMING SLIGHTLY. IFR TO LIFR CONDITIONS ARE POSSIBLE AS THIS LOW STRATUS BUILDS IN. PATCHY FOG WILL ALSO BE POSSIBLE. WINDS WILL BECOME SOUTHERLY THROUGH THE PERIOD AND BY THE END OF THE FORECAST PERIOD THEY WILL BE SOUTHERLY AND INCREASING WHICH WILL HELP TO ERODETHE LOW STRATUS AND IMPROVE FLIGHT CONDITIONS. BILLINGS WRIGHT && .FIRE WEATHER... ISSUED AT 357 AM CDT TUE MAR 31 2015 FIRE WEATHER CONCERNS REMAIN GREATEST FOR WEDNESDAY AFTERNOON. DESPITE HIGHER DEWPOINTS SPREADING NORTH ACROSS KS SOUTHERLY WINDS OF 25-35 MPH WILL POSE A VERY HIGH TO EXTREME FIRE DANGER ACROSS THE REGION. STAY TUNED. && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 85 57 85 55 / 0 10 10 40 HUTCHINSON 84 55 86 51 / 0 10 10 50 NEWTON 83 56 84 52 / 0 10 10 50 ELDORADO 83 56 83 55 / 0 10 10 50 WINFIELD-KWLD 85 57 83 57 / 0 10 10 30 RUSSELL 85 55 88 46 / 0 0 20 50 GREAT BEND 84 55 87 47 / 0 10 20 50 SALINA 84 55 87 49 / 0 10 10 70 MCPHERSON 84 55 85 50 / 0 10 10 60 COFFEYVILLE 84 56 80 61 / 0 10 20 30 CHANUTE 81 56 79 58 / 0 10 20 40 IOLA 80 55 80 57 / 0 10 20 50 PARSONS-KPPF 83 56 80 60 / 0 10 20 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1200 PM CDT TUE MAR 31 2015 ...UPDATED AVIATION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CDT TUE MAR 31 2015 WATER VAPOR LOOP + RAP ANALYSIS DURING THE OVERNIGHT HOURS REVEALED A SPLIT JET SYNOPTIC SETUP ACROSS WESTERN NORTH AMERICA WITH RIDGING IN THE NORTHERN BRANCH ACROSS THE CENTRAL/NORTHERN ROCKIES. SOUTH OF THE NORTHERN BRANCH RIDGE, AN UPPER LOW IN THE SOUTHERN STREAM WAS MOVING THROUGH CENTRAL BAJA CALIFORNIA WITH HIGH LEVEL CIRRIFORM CLOUD SPREADING INTO SOUTHWEST TEXAS. WESTERN KANSAS WAS INFLUENCED BY A FAIRLY WEAK NORTHWEST FLOW IN THE UPPER TROPOSPHERE DOWNSTREAM FROM THE AFOREMENTIONED RIDGE AXIS. A STORM SYSTEM IN THE NORTHERN BRANCH WAS MOVING INTO THE PACIFIC NORTHWEST REGION, WHICH WILL ALLOW A DEEPENING LEE TROUGH ACROSS THE NORTHERN AND CENTRAL HIGH PLAINS LATE TODAY. THIS WILL RESULT IN A VEERING OF SURFACE WINDS FROM THE EAST-NORTHEAST THIS MORNING TO THE SOUTHEAST BY AFTERNOON ACROSS WESTERN KANSAS. THE REALLY WEAK FRONT THAT PUSHED THROUGH OVERNIGHT WILL DISSOLVE COMPLETELY WITH SOUTHEAST WINDS DEVELOPING ALL THE WAY DOWN INTO THE SOUTHERN PLAINS BY TONIGHT, THIS WILL OPEN THE FLOODGATES TO SOME FAIRLY ABUNDANT GULF OF MEXICO MOISTURE INTO KANSAS. SURFACE DEWPOINTS WILL RISE TO THE LOWER-MID 50S, PARTICULARLY EAST OF HIGHWAY 283 AFTER 06Z TONIGHT. THIS ABUNDANCE OF MOISTURE SHOULD RESULT IN SOME VERY LOW STRATUS AND/OR AREAS OF FOG. WE WILL KEEP THE FOG MENTION OUT OF THE FORECAST FOR NOW, BUT THE DAY SHIFT WILL NEED TO RE-EVALUATE THIS. AS FAR AS TEMPERATURES GO TODAY, HIGHS IN THE UPPER 70S TO LOWER 80S AREAWIDE ARE FORECAST, WHICH IS NO CHANGE FROM THE PREVIOUS FORECAST. TONIGHTS TEMPERATURES SHOULD BE MILD WITH THE INCREASE IN LOW LEVEL MOISTURE WITH LOWS IN THE LOWER TO MID 50S ALONG/EAST OF HIGHWAY 283. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 400 AM CDT TUE MAR 31 2015 SOME OF THE WARMEST TEMPERATURES OF THE SEASON SO FAR, IF NOT THE ABSOLUTE WARMEST WILL BE FELT ACROSS CENTRAL ANS SOUTHWEST KANSAS ON WEDNESDAY AFTERNOON. THE ECMWF AND GFS ARE IN GOOD AGREEMENT WITH A BROAD SURFACE LOW PRESSURE DEVELOPING OVER WESTERN KS, DRAWING A COLORADO AIRMASS DOWNSLOPE ACROSS WESTERN KS AND PROMOTING STRONG ADIABATIC WARMING IN ADDITION TOP STRONG INSOLATION. AT THIS TIME EVEN THE BLEND SOLUTIONS SUGGEST MID TO UPPER 80S ACROSS ALL OF WESTERN AND CENTRAL KANSAS, WHICH PROBABLY SUGGESTS 90 DEGREES MIGHT BE POSSIBLE ESPECIALLY IN THE RED HILLS REGION. OVERALL THE AREA APPEARS TOO DRY FOR CONVECTION IN THE WESTERN SECTIONS OF THE DDC FORECAST AREA ON WEDNESDAY. HOWEVER A COLD FRONT IS EXPECTED TO ARRIVE LATE, WHICH WILL BE THE FOCUS FOR SHOWERS AND STORMS WELL TO THE EAST OF THE REGION, AND CANNOT BE RULED OUT ALONG THE FRONT INTO CENTRAL KANSAS IF SURFACE MOISTURE CONVERGENCE BECOMES STRONG. FOR THIS REASON, WE`VE LEFT THE POPS UNCHANGED IN THE 20 TO 30 PERCENT RANGE FOR THIS TIMEFRAME. MOREOVER THE MESOSCALE CONVECTIVE ALLOWING MODELS INDICATE CONVECTION COULD START MUCH EARLIER ALONG THE DIFFUSE DRYLINE AND BETTER MOISTURE ZONE, WHICH WOULD LEND ITSELF TO A FAVORED CHANCE FOR A FEW SEVERE STORMS WITH HAIL. 850-500 MB MUCAPES ON THE ORDER OF 1500 J/KG AND POTENTIALLY 30+ KNOTS OF BULK SHEAR MAY SPAWN A FEW MAINLY HAIL PRODUCING SUPERCELLS EAST OF A WAKEENEY TO GARDEN LINE. A LIMITED PORTION OF CENTRAL KANSAS IS CURRENTLY OUTLOOKED FOR A SLIGHT RISK OF SEVERE. DIURNAL HIGH TEMPERATURES WILL SLIDE THROUGH THE 60S ON FRIDAY AND INTO THE 50S BY FRIDAY INFLUENCED BY COLD ADVECTION, CLOUDS AND RAIN THURSDAY NIGHT. SNOW SHOWERS ARE POSSIBLE AS WELL FAR WEST, ALTHOUGH AT THIS TIME A LARGE DEGREE OF UNCERTAINTY EXISTS WITH RESPECT TO SURFACE TEMPERATURES. ANY SNOW DEVELOPING WOULD BE HIGHLY DEPENDENT ON THE SURFACE WET BULB COOLING. THE LEFT FRONT EXIT REGION OF THE UPPER JET SHOULD INTERSECT A MID LEVEL BAROCLINIC ZONE, DURING THIS TIMEFRAME, PROMOTING HIGHER CONFIDENCE AND THUS INCREASED POPS THURSDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1200 PM CDT TUE MAR 31 2015 MOISTURE FROM OKLAHOMA SHOULD CONTINUE TO ADVECT NORTHWARD THROUGH THE OVERNIGHT PERIOD. THE MAIN QUESTION FOR NOW IS HOW LOW VIS WILL GET IN ASSOCIATION WITH THE INCREASING MOISTURE AND BR. FOR NOW, WILL TREND DOWN AND PUT MVFR CONDITIONS FOR KDDC FOR TOMORROW MORNING. SOME GUIDANCE IS LOWER THAN MVFR AND WILL LET LATER SHIFTS ADJUST AS CERTAINTY INCREASES WITH TIME. NOT CONFIDENT ENOUGH TO HAVE LOWER FLIGHT CONDITIONS FOR KGCK/KHYS AT THIS TIME. && .FIRE WEATHER... ISSUED AT 400 AM CDT TUE MAR 31 2015 ELEVATED FIRE WEATHER CONDITIONS ARE EXPECTED ON WEDNESDAY, ALTHOUGH RED FLAG CONDITIONS DO NOT APPEAR LIKELY TO OCCUR. A DRY AIRMASS WILL DESCEND ACROSS THE PLAINS INTO CENTRAL KANSAS EARLY WEDNESDAY ALLOWING TEMPERATURES TO SOAR AND RELATIVE HUMIDITIES TO PLUMMET TO 20 PERCENT AND LOWER. SINGLE DIGIT RELATIVE HUMIDITIES ARE POSSIBLE IN THE FAR WEST WHERE WELL CURED FUELS ARE STILL FOUND. THE LEVEL OF UNCERTAINTY IS FOCUSED REALLY ONLY ON WIND SPEEDS WHICH AT THIS TIME DO NOT APPEAR STRONG ENOUGH TO WARRANT FIRE WEATHER WATCH HEADLINES. A COLD FRONT THURSDAY BEARS WATCHING, HOWEVER TEMPERATURES SHOULD BE SIGNIFICANTLY COOLER. && .PRELIMINARY POINT TEMPS/POPS... DDC 83 54 89 46 / 0 10 40 50 GCK 82 51 89 42 / 0 0 40 40 EHA 80 51 86 43 / 0 0 20 10 LBL 82 52 89 45 / 10 0 30 10 HYS 83 53 86 44 / 0 0 40 50 P28 83 55 87 52 / 10 10 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...UMSCHEID LONG TERM...RUSSELL AVIATION...SUGDEN FIRE WEATHER...RUSSELL
AREA FORECAST DISCUSSION
NWS WICHITA KS
1046 AM CDT TUE MAR 31 2015 .SYNOPSIS... ISSUED AT 357 AM CDT TUE MAR 31 2015 EARLY THIS MORNING A SURFACE TROF EXTENDED FROM THE IA/MO BORDER THRU CENTRAL KS TO THE TX PANHANDLE. MOST TEMPERATURES ACROSS KICT COUNTRY WERE IN THE 45-55 DEGREE RANGE. UNDER MOSTLY CLEAR SKIES. && .UPDATE... ISSUED AT 1040 AM CDT TUE MAR 31 2015 HAVE UPDATED TEMPERATURES ACROSS THE AREA THIS MORNING. AS OF 1040AM THE TEMPERATURE AT EISENHOWER AIRPORT WAS ALREADY 70 DEGREES WHICH WAS SIGNIFICANTLY UNDER FORECAST WHICH WAS ONE OF MANY ACROSS THE FORECAST AREA. THE RAP SEEMED TO HAVE THE BEST HANDLE ON THE CURRENT TRENDS AND USED THAT AS GUIDANCE FOR THE FORECAST THROUGH THE AFTERNOON AND AFTERNOON HIGHS. INCREASED HIGHS TODAY A FEW DEGREES ACROSS THE AREA AND DECREASED DEWPOINTS ACROSS THE AREA. BILLINGS WRIGHT && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 357 AM CDT TUE MAR 31 2015 TODAY & TONIGHT: QUIET WEATHER CONTINUES ACROSS THE NEIGHBORHOOD AS A BROAD UPPER DECK RIDGE SPREADS EAST ACROSS THE NORTHERN AND CENTRAL PLAINS. HAVE KEPT MENTION OF PATCHY FOG IN SOUTHEAST KS FOR EARLY THIS MORNING AS MUCH HIGHER DEWPOINTS IN THE MID & UPPER 50S ARE MIGRATING TOWARD THIS AREA. LATE THIS AFTERNOON...A WEAK SURFACE TROF WILL DEVELOP OVER THE WESTERN PLAINS IN RESPONSE TO A MID- LEVEL SHORTWAVE DEVELOPING OVER THE WESTERN RIO GRANDE & WOULD ALSO INDUCE WARM FRONTOGENESIS ACROSS THE SOUTHERN PLAINS. DESPITE EASTERLY WINDS AROUND 10 MPH SUN-DRENCHED SKIES WILL ENABLE TEMPERATURES TO REACH AROUND 80 IN MOST AREAS. TONIGHT`S TEMPERATURES WILL BE MUCH WARMER AS GULF MOISTURE MIGRATES ACROSS KS. WEDNESDAY & WEDNESDAY NIGHT: THESE PERIODS CONTINUE TO DRAW THE GREATEST ATTENTION. AN UPPER DECK WAVE THAT`LL MOVE EAST ACROSS THE PACIFIC NORTHWEST ON TUESDAY WILL STRENGTHEN AS IT CROSSES THE NORTHERN & CENTRAL ROCKIES TO ALONG THE U.S./CANADIAN BORDER ON WED. THIS CHARACTER WOULD INDUCE THE WESTERN PLAINS SURFACE TROF TO STRENGTHEN WHICH WOULD RESULT IN MUCH WARMER AND INCREASINGLY WINDY WEATHER ACROSS THE NEIGHBORHOOD WEDNESDAY AFTERNOON. DESPITE HIGHER DEWPOINTS CONTINUING TO MIGRATE INTO KS THE STRONG SOUTHERLY WINDS ARE INDICATING THAT AN EXTREME FIRE DANGER IS LIKELY OVER PARTS OF CENTRAL & SOUTH-CENTRAL KS WED AFTERNOON. A FIRE WEATHER WATCH MAY BE REQUIRED FOR WEDNESDAY AFTERNOON. STAY TUNED. THE GREATEST THUNDERSTORM POTENTIAL IS STILL SLATED TO OCCUR WEDNESDAY NIGHT AS THE AFORE-MENTIONED UPPER-DECK WILL SWEEP A COLD FRONT SE INTO A MOIST AND UNSTABLE AIRMASS. MCS DEVELOPMENT IS LIKELY WITH THE MCS SURGING EAST ACROSS PRIMARILY NORTHERN KS & SOUTHERN NEBRASKA. THE RAPID SE-MOVING COLD FRONT DICTATES FINE- TUNING GREATEST CHANCES OF THUNDERSTORMS WITH CENTRAL KS DURING THE EVENING AND EASTERN KS LATER IN THE NIGHT. THURSDAY & THURSDAY NIGHT: THE SE PROGRESS OF THE COLD FRONT WILL HAVE TO BE WATCHED CLOSELY AS IT WILL DECELERATE AS IT VENTURES INTO SE KS & OK. HAVE KEPT HIGHEST POPS ACROSS SE KS WHERE CLOSER TO THE FRONT. POST-FRONTAL SHOWERS ARE POSSIBLE FOR THE REST OF THE NEIGHBORHOOD WHERE MOIST EASTERLY FLOW PREVAILS. .LONG TERM...(FRIDAY THROUGH MONDAY) ISSUED AT 357 AM CDT TUE MAR 31 2015 QUIET WEATHER IS EXPECTED FOR MOST OF THESE PERIODS AS BROAD RIDGE SPREADS EAST ACROSS THE PLAINS. ES && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 641 AM CDT TUE MAR 31 2015 A WEAK SURFACE TROUGH WILL CONTINUES TO DROP SOUTH ACROSS THE FORECAST AREA THIS MORNING...WHICH WILL LEAD TO A GRADUAL WIND SHIFT TO THE NORTHEAST AND EAST FOR MOST LOCATIONS. RICH MOISTURE JUST AHEAD OF THIS TROUGH MAY LEAD TO SOME MVFR FOG OVER SE KS FOR A FEW HOURS THIS MORNING. OTHERWISE EXPECT VFR CONDITIONS ACROSS THE REGION FOR MOST OF THE DAYLIGHT HOURS INTO THE EVENING HOURS. EXPECT THE SURFACE WINDS TO GRADUALLY SHIFT TO THE SOUTHEAST AS A WARM FRONT PUSHES BACK NORTH ACROSS THE FORECAST AREA THIS EVENING. AS THIS MOISTURE RICH AIR MOVES BACK NORTH...EXPECT LOW LEVEL MOISTURE TO INCREASE INITIALLY OVER SOUTH CENTRAL KS. THIS WILL LEAD TO SOME IFR CIGS MOVING INTO THE KICT/KHUT TAF SITES AFTER 09Z/WED. WILL ALSO HAVE TO KEEP AN EYE OUT FOR SOME MVFR FOG AS WELL...BUT WILL NOT MENTION THIS JUST YET...AS WINDS WILL PROBABLY STAY UP ENOUGH TO PREVENT FOG FORMATION. KETCHAM && .FIRE WEATHER... ISSUED AT 357 AM CDT TUE MAR 31 2015 FIRE WEATHER CONCERNS REMAIN GREATEST FOR WEDNESDAY AFTERNOON. DESPITE HIGHER DEWPOINTS SPREADING NORTH ACROSS KS SOUTHERLY WINDS OF 25-35 MPH WILL POSE A VERY HIGH TO EXTREME FIRE DANGER ACROSS THE REGION. STAY TUNED. && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 85 57 85 55 / 0 10 10 40 HUTCHINSON 84 55 86 51 / 0 10 10 50 NEWTON 83 56 84 52 / 0 10 10 50 ELDORADO 82 56 83 55 / 0 10 10 50 WINFIELD-KWLD 85 57 83 57 / 0 10 10 30 RUSSELL 84 55 88 46 / 0 0 20 50 GREAT BEND 83 55 87 47 / 0 10 20 50 SALINA 83 55 87 49 / 0 0 10 70 MCPHERSON 83 55 85 50 / 0 10 10 60 COFFEYVILLE 84 56 80 61 / 0 10 20 30 CHANUTE 81 56 79 58 / 0 10 20 40 IOLA 80 55 80 57 / 0 10 20 50 PARSONS-KPPF 83 56 80 60 / 0 10 20 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
701 AM CDT TUE MAR 31 2015 ...UPDATED AVIATION SECTION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CDT TUE MAR 31 2015 WATER VAPOR LOOP + RAP ANALYSIS DURING THE OVERNIGHT HOURS REVEALED A SPLIT JET SYNOPTIC SETUP ACROSS WESTERN NORTH AMERICA WITH RIDGING IN THE NORTHERN BRANCH ACROSS THE CENTRAL/NORTHERN ROCKIES. SOUTH OF THE NORTHERN BRANCH RIDGE, AN UPPER LOW IN THE SOUTHERN STREAM WAS MOVING THROUGH CENTRAL BAJA CALIFORNIA WITH HIGH LEVEL CIRRIFORM CLOUD SPREADING INTO SOUTHWEST TEXAS. WESTERN KANSAS WAS INFLUENCED BY A FAIRLY WEAK NORTHWEST FLOW IN THE UPPER TROPOSPHERE DOWNSTREAM FROM THE AFOREMENTIONED RIDGE AXIS. A STORM SYSTEM IN THE NORTHERN BRANCH WAS MOVING INTO THE PACIFIC NORTHWEST REGION, WHICH WILL ALLOW A DEEPENING LEE TROUGH ACROSS THE NORTHERN AND CENTRAL HIGH PLAINS LATE TODAY. THIS WILL RESULT IN A VEERING OF SURFACE WINDS FROM THE EAST-NORTHEAST THIS MORNING TO THE SOUTHEAST BY AFTERNOON ACROSS WESTERN KANSAS. THE REALLY WEAK FRONT THAT PUSHED THROUGH OVERNIGHT WILL DISSOLVE COMPLETELY WITH SOUTHEAST WINDS DEVELOPING ALL THE WAY DOWN INTO THE SOUTHERN PLAINS BY TONIGHT, THIS WILL OPEN THE FLOODGATES TO SOME FAIRLY ABUNDANT GULF OF MEXICO MOISTURE INTO KANSAS. SURFACE DEWPOINTS WILL RISE TO THE LOWER-MID 50S, PARTICULARLY EAST OF HIGHWAY 283 AFTER 06Z TONIGHT. THIS ABUNDANCE OF MOISTURE SHOULD RESULT IN SOME VERY LOW STRATUS AND/OR AREAS OF FOG. WE WILL KEEP THE FOG MENTION OUT OF THE FORECAST FOR NOW, BUT THE DAY SHIFT WILL NEED TO RE-EVALUATE THIS. AS FAR AS TEMPERATURES GO TODAY, HIGHS IN THE UPPER 70S TO LOWER 80S AREAWIDE ARE FORECAST, WHICH IS NO CHANGE FROM THE PREVIOUS FORECAST. TONIGHTS TEMPERATURES SHOULD BE MILD WITH THE INCREASE IN LOW LEVEL MOISTURE WITH LOWS IN THE LOWER TO MID 50S ALONG/EAST OF HIGHWAY 283. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 400 AM CDT TUE MAR 31 2015 SOME OF THE WARMEST TEMPERATURES OF THE SEASON SO FAR, IF NOT THE ABSOLUTE WARMEST WILL BE FELT ACROSS CENTRAL ANS SOUTHWEST KANSAS ON WEDNESDAY AFTERNOON. THE ECMWF AND GFS ARE IN GOOD AGREEMENT WITH A BROAD SURFACE LOW PRESSURE DEVELOPING OVER WESTERN KS, DRAWING A COLORADO AIRMASS DOWNSLOPE ACROSS WESTERN KS AND PROMOTING STRONG ADIABATIC WARMING IN ADDITION TOP STRONG INSOLATION. AT THIS TIME EVEN THE BLEND SOLUTIONS SUGGEST MID TO UPPER 80S ACROSS ALL OF WESTERN AND CENTRAL KANSAS, WHICH PROBABLY SUGGESTS 90 DEGREES MIGHT BE POSSIBLE ESPECIALLY IN THE RED HILLS REGION. OVERALL THE AREA APPEARS TOO DRY FOR CONVECTION IN THE WESTERN SECTIONS OF THE DDC FORECAST AREA ON WEDNESDAY. HOWEVER A COLD FRONT IS EXPECTED TO ARRIVE LATE, WHICH WILL BE THE FOCUS FOR SHOWERS AND STORMS WELL TO THE EAST OF THE REGION, AND CANNOT BE RULED OUT ALONG THE FRONT INTO CENTRAL KANSAS IF SURFACE MOISTURE CONVERGENCE BECOMES STRONG. FOR THIS REASON, WE`VE LEFT THE POPS UNCHANGED IN THE 20 TO 30 PERCENT RANGE FOR THIS TIMEFRAME. MOREOVER THE MESOSCALE CONVECTIVE ALLOWING MODELS INDICATE CONVECTION COULD START MUCH EARLIER ALONG THE DIFFUSE DRYLINE AND BETTER MOISTURE ZONE, WHICH WOULD LEND ITSELF TO A FAVORED CHANCE FOR A FEW SEVERE STORMS WITH HAIL. 850-500 MB MUCAPES ON THE ORDER OF 1500 J/KG AND POTENTIALLY 30+ KNOTS OF BULK SHEAR MAY SPAWN A FEW MAINLY HAIL PRODUCING SUPERCELLS EAST OF A WAKEENEY TO GARDEN LINE. A LIMITED PORTION OF CENTRAL KANSAS IS CURRENTLY OUTLOOKED FOR A SLIGHT RISK OF SEVERE. DIURNAL HIGH TEMPERATURES WILL SLIDE THROUGH THE 60S ON FRIDAY AND INTO THE 50S BY FRIDAY INFLUENCED BY COLD ADVECTION, CLOUDS AND RAIN THURSDAY NIGHT. SNOW SHOWERS ARE POSSIBLE AS WELL FAR WEST, ALTHOUGH AT THIS TIME A LARGE DEGREE OF UNCERTAINTY EXISTS WITH RESPECT TO SURFACE TEMPERATURES. ANY SNOW DEVELOPING WOULD BE HIGHLY DEPENDENT ON THE SURFACE WET BULB COOLING. THE LEFT FRONT EXIT REGION OF THE UPPER JET SHOULD INTERSECT A MID LEVEL BAROCLINIC ZONE, DURING THIS TIMEFRAME, PROMOTING HIGHER CONFIDENCE AND THUS INCREASED POPS THURSDAY NIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 700 AM CDT TUE MAR 31 2015 LIGHT NORTHERLY WINDS WILL SLOWLY VEER TO THE SOUTH BY LATER IN THE AFTERNOON, WITH WEAK GUSTS TO AROUND 20 KNOTS IN THE AFTERNOON. VFR CONDITIONS ARE EXPECTED THROUGH THE BULK OF THE TIMEFRAME AT ALL TAF SITES, HOWEVER FOG MAY DEVELOP BY EARLY WEDNESDAY MORNING IN VICINITY OF DDC AS THE MORE MOIST AIRMASS OVER OKLAHOMA SPREADS NORTH. && .FIRE WEATHER... ISSUED AT 400 AM CDT TUE MAR 31 2015 ELEVATED FIRE WEATHER CONDITIONS ARE EXPECTED ON WEDNESDAY, ALTHOUGH RED FLAG CONDITIONS DO NOT APPEAR LIKELY TO OCCUR. A DRY AIRMASS WILL DESCEND ACROSS THE PLAINS INTO CENTRAL KANSAS EARLY WEDNESDAY ALLOWING TEMPERATURES TO SOAR AND RELATIVE HUMIDITIES TO PLUMMET TO 20 PERCENT AND LOWER. SINGLE DIGIT RELATIVE HUMIDITIES ARE POSSIBLE IN THE FAR WEST WHERE WELL CURED FUELS ARE STILL FOUND. THE LEVEL OF UNCERTAINTY IS FOCUSED REALLY ONLY ON WIND SPEEDS WHICH AT THIS TIME DO NOT APPEAR STRONG ENOUGH TO WARRANT FIRE WEATHER WATCH HEADLINES. A COLD FRONT THURSDAY BEARS WATCHING, HOWEVER TEMPERATURES SHOULD BE SIGNIFICANTLY COOLER. && .PRELIMINARY POINT TEMPS/POPS... DDC 81 52 86 46 / 10 10 30 20 GCK 81 49 87 42 / 10 10 30 20 EHA 82 49 86 43 / 10 10 10 20 LBL 82 49 88 45 / 10 10 20 20 HYS 79 51 85 44 / 0 10 30 30 P28 84 55 86 52 / 10 10 10 20 && .DDC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...UMSCHEID LONG TERM...RUSSELL AVIATION...RUSSELL FIRE WEATHER...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
403 AM CDT TUE MAR 31 2015 ...UPDATED SHORT TERM, LONG TERM, FIRE WEATHER SECTIONS... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CDT TUE MAR 31 2015 WATER VAPOR LOOP + RAP ANALYSIS DURING THE OVERNIGHT HOURS REVEALED A SPLIT JET SYNOPTIC SETUP ACROSS WESTERN NORTH AMERICA WITH RIDGING IN THE NORTHERN BRANCH ACROSS THE CENTRAL/NORTHERN ROCKIES. SOUTH OF THE NORTHERN BRANCH RIDGE, AN UPPER LOW IN THE SOUTHERN STREAM WAS MOVING THROUGH CENTRAL BAJA CALIFORNIA WITH HIGH LEVEL CIRRIFORM CLOUD SPREADING INTO SOUTHWEST TEXAS. WESTERN KANSAS WAS INFLUENCED BY A FAIRLY WEAK NORTHWEST FLOW IN THE UPPER TROPOSPHERE DOWNSTREAM FROM THE AFOREMENTIONED RIDGE AXIS. A STORM SYSTEM IN THE NORTHERN BRANCH WAS MOVING INTO THE PACIFIC NORTHWEST REGION, WHICH WILL ALLOW A DEEPENING LEE TROUGH ACROSS THE NORTHERN AND CENTRAL HIGH PLAINS LATE TODAY. THIS WILL RESULT IN A VEERING OF SURFACE WINDS FROM THE EAST-NORTHEAST THIS MORNING TO THE SOUTHEAST BY AFTERNOON ACROSS WESTERN KANSAS. THE REALLY WEAK FRONT THAT PUSHED THROUGH OVERNIGHT WILL DISSOLVE COMPLETELY WITH SOUTHEAST WINDS DEVELOPING ALL THE WAY DOWN INTO THE SOUTHERN PLAINS BY TONIGHT, THIS WILL OPEN THE FLOODGATES TO SOME FAIRLY ABUNDANT GULF OF MEXICO MOISTURE INTO KANSAS. SURFACE DEWPOINTS WILL RISE TO THE LOWER-MID 50S, PARTICULARLY EAST OF HIGHWAY 283 AFTER 06Z TONIGHT. THIS ABUNDANCE OF MOISTURE SHOULD RESULT IN SOME VERY LOW STRATUS AND/OR AREAS OF FOG. WE WILL KEEP THE FOG MENTION OUT OF THE FORECAST FOR NOW, BUT THE DAY SHIFT WILL NEED TO RE-EVALUATE THIS. AS FAR AS TEMPERATURES GO TODAY, HIGHS IN THE UPPER 70S TO LOWER 80S AREAWIDE ARE FORECAST, WHICH IS NO CHANGE FROM THE PREVIOUS FORECAST. TONIGHTS TEMPERATURES SHOULD BE MILD WITH THE INCREASE IN LOW LEVEL MOISTURE WITH LOWS IN THE LOWER TO MID 50S ALONG/EAST OF HIGHWAY 283. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 400 AM CDT TUE MAR 31 2015 SOME OF THE WARMEST TEMPERATURES OF THE SEASON SO FAR, IF NOT THE ABSOLUTE WARMEST WILL BE FELT ACROSS CENTRAL ANS SOUTHWEST KANSAS ON WEDNESDAY AFTERNOON. THE ECMWF AND GFS ARE IN GOOD AGREEMENT WITH A BROAD SURFACE LOW PRESSURE DEVELOPING OVER WESTERN KS, DRAWING A COLORADO AIRMASS DOWNSLOPE ACROSS WESTERN KS AND PROMOTING STRONG ADIABATIC WARMING IN ADDITION TOP STRONG INSOLATION. AT THIS TIME EVEN THE BLEND SOLUTIONS SUGGEST MID TO UPPER 80S ACROSS ALL OF WESTERN AND CENTRAL KANSAS, WHICH PROBABLY SUGGESTS 90 DEGREES MIGHT BE POSSIBLE ESPECIALLY IN THE RED HILLS REGION. OVERALL THE AREA APPEARS TOO DRY FOR CONVECTION IN THE WESTERN SECTIONS OF THE DDC FORECAST AREA ON WEDNESDAY. HOWEVER A COLD FRONT IS EXPECTED TO ARRIVE LATE, WHICH WILL BE THE FOCUS FOR SHOWERS AND STORMS WELL TO THE EAST OF THE REGION, AND CANNOT BE RULED OUT ALONG THE FRONT INTO CENTRAL KANSAS IF SURFACE MOISTURE CONVERGENCE BECOMES STRONG. FOR THIS REASON, WE`VE LEFT THE POPS UNCHANGED IN THE 20 TO 30 PERCENT RANGE FOR THIS TIMEFRAME. MOREOVER THE MESOSCALE CONVECTIVE ALLOWING MODELS INDICATE CONVECTION COULD START MUCH EARLIER ALONG THE DIFFUSE DRYLINE AND BETTER MOISTURE ZONE, WHICH WOULD LEND ITSELF TO A FAVORED CHANCE FOR A FEW SEVERE STORMS WITH HAIL. 850-500 MB MUCAPES ON THE ORDER OF 1500 J/KG AND POTENTIALLY 30+ KNOTS OF BULK SHEAR MAY SPAWN A FEW MAINLY HAIL PRODUCING SUPERCELLS EAST OF A WAKEENEY TO GARDEN LINE. A LIMITED PORTION OF CENTRAL KANSAS IS CURRENTLY OUTLOOKED FOR A SLIGHT RISK OF SEVERE. DIURNAL HIGH TEMPERATURES WILL SLIDE THROUGH THE 60S ON FRIDAY AND INTO THE 50S BY FRIDAY INFLUENCED BY COLD ADVECTION, CLOUDS AND RAIN THURSDAY NIGHT. SNOW SHOWERS ARE POSSIBLE AS WELL FAR WEST, ALTHOUGH AT THIS TIME A LARGE DEGREE OF UNCERTAINTY EXISTS WITH RESPECT TO SURFACE TEMPERATURES. ANY SNOW DEVELOPING WOULD BE HIGHLY DEPENDENT ON THE SURFACE WET BULB COOLING. THE LEFT FRONT EXIT REGION OF THE UPPER JET SHOULD INTERSECT A MID LEVEL BAROCLINIC ZONE, DURING THIS TIMEFRAME, PROMOTING HIGHER CONFIDENCE AND THUS INCREASED POPS THURSDAY NIGHT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1249 AM CDT TUE MAR 31 2015 FAIRLY TRANQUIL AVIATION WEATHER IS ANTICIPATED THROUGH TUESDAY. LIGHT WINDS OVERNIGHT THROUGH EARLY MORNING WILL GIVE WAY TO AN EASTERLY WIND BY MID TO LATE MORNING...BECOMING SOUTHEASTERLY BY LATE IN THE DAY. WIND SPEEDS SHOULD RANGE FROM 12 TO 15 KNOTS. THE SOUTHEAST WINDS WILL DRAW UP LOW LEVEL MOISTURE, WHICH WILL LEAD TO DETERIORATING CEILINGS AND/OR VISIBILITY BY EARLY WEDNESDAY MORNING (A LITTLE BIT BEYOND THIS FORECAST PERIOD). && .FIRE WEATHER... ISSUED AT 400 AM CDT TUE MAR 31 2015 ELEVATED FIRE WEATHER CONDITIONS ARE EXPECTED ON WEDNESDAY, ALTHOUGH RED FLAG CONDITIONS DO NOT APPEAR LIKELY TO OCCUR. A DRY AIRMASS WILL DESCEND ACROSS THE PLAINS INTO CENTRAL KANSAS EARLY WEDNESDAY ALLOWING TEMPERATURES TO SOAR AND RELATIVE HUMIDITIES TO PLUMMET TO 20 PERCENT AND LOWER. SINGLE DIGIT RELATIVE HUMIDITIES ARE POSSIBLE IN THE FAR WEST WHERE WELL CURED FUELS ARE STILL FOUND. THE LEVEL OF UNCERTAINTY IS FOCUSED REALLY ONLY ON WIND SPEEDS WHICH AT THIS TIME DO NOT APPEAR STRONG ENOUGH TO WARRANT FIRE WEATHER WATCH HEADLINES. A COLD FRONT THURSDAY BEARS WATCHING, HOWEVER TEMPERATURES SHOULD BE SIGNIFICANTLY COOLER. && .PRELIMINARY POINT TEMPS/POPS... DDC 81 53 85 47 / 10 10 20 20 GCK 81 50 87 45 / 10 10 20 20 EHA 82 50 85 45 / 10 10 10 20 LBL 82 52 87 46 / 10 10 20 20 HYS 79 53 84 45 / 0 10 30 30 P28 84 55 84 53 / 10 10 20 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...UMSCHEID LONG TERM...RUSSELL AVIATION...UMSCHEID FIRE WEATHER...RUSSELL
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
959 PM CDT WED APR 1 2015 .DISCUSSION... SCT CONVECTION HAS FINALLY BEGUN TO DIMINISH ACROSS THE REGION AS OF MID-EVENING...AS INSTABILITY HAS DIMINISHED SINCE THE SETTING SUN. THE EVENING WATER VAPOR IMAGERY INDICATES THE TAIL END OF A SHORTWAVE TROUGH EXTENDING FROM NW AR INTO SE OK/ECNTRL TX...AND SHOULD CONTINUE TO SHIFT E ACROSS THE REGION OVERNIGHT...EXITING THE AREA STAGE RIGHT SHORTLY AFTER 12Z THURSDAY. WHILE THE 00Z NAM HAS HANDLED THE ONGOING AREA OF -SHRA POORLY...THE LATEST HRRR HAS NOT...AND MAINTAINS THESE -SHRA OVER DEEP E TX/LOWER TOLEDO BEND COUNTRY LATE THIS EVENING...AND WITH ADDITIONAL REDEVELOPMENT POSSIBLE OVER NCNTRL LA AS LARGE SCALE FORCING SPREADS E WITH THE TROUGH. HOWEVER...THIS AREA IS WORKED OVER FROM THE LATE AFTERNOON/EARLY EVENING CONVECTION...THUS THE POTENTIAL FOR DEEP CONVECTION APPEARS TO HAVE GREATLY DIMINISHED. A 30-40KT SWRLY LLJ IS PROGGED TO DEVELOP LATE...WHICH SHOULD RESULT IN THE RAPID INCREASE IN LOW STRATUS LATE. THIS SHOULD LIFT BY MIDDAY THURSDAY...WITH SOME OF THE STRONGER WINDS MIXING DOWN RESULTING IN GUSTY SRLY WINDS OVER AT LEAST THE WRN HALF OF THE AREA. WILL ALLOW THE MID SHIFT TO ANALYZE THE ENTIRE SUITE OF 00Z DATA TONIGHT...WITH A LAKE WIND ADVISORY POSSIBLE THURSDAY. HAVE UPDATED THE ZONES TO ADJUST POPS PER CURRENT RADAR TRENDS...MAINLY TO INCREASE POPS TO CHANCE ACROSS DEEP E TX/NCNTRL LA. DID LOWER POPS TO SLIGHT CHANCE AREAWIDE THURSDAY...AS THE TROUGH/STRONGEST FORCING WILL REMAIN E OF THE AREA. MADE ONLY MINIMAL CHANGES TO MIN TEMPS...AS WINDS/CLOUD COVER WILL KEEP TEMPS IN THE MID/UPPER 60S. ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY. 15 && .PREV DISCUSSION... /ISSUED 641 PM CDT WED APR 1 2015/ AVIATION... SOUTHERLY WINDS FROM 10-15 KTS AND SOME VARIABLE HIGHER GUSTS NEAR 25 KTS WITH SOME CONVECTIVE OUTFLOWS ROAMING AROUND...NAMELY KSHV/KMLU. AN UPPER LEVEL DISTURBANCE IS TRACKING ACROSS CNTRL TX AND COULD BRING SOME ADDITIONAL ISOLD TSTMS THIS EVENING THROUGH ABOUT OUR NEXT TAF ISSUANCE...BUT WITH LOSS OF HEATING...WE WILL AMEND FOR ANY SUCH WITH FURTHER DIMINISHING CHANCES OVERNIGHT AS LOW CLOUDS AND PATCHY FOG RETURN ONCE AGAIN LINGERING INTO MID MORNING. CLIMB WINDS ARE SW 10-25KTS VEERING TO WEST BY 10KFT. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 66 81 68 80 / 30 20 10 40 MLU 64 83 66 81 / 30 20 10 50 DEQ 63 78 64 74 / 20 20 30 40 TXK 65 80 66 77 / 30 20 20 40 ELD 64 82 66 79 / 30 20 10 40 TYR 66 82 68 78 / 30 20 10 40 GGG 67 82 68 79 / 30 20 10 40 LFK 67 84 69 80 / 40 20 10 50 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 15
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
702 PM EDT TUE MAR 31 2015 .SYNOPSIS... HIGH PRESSURE PROVIDES A MAINLY DRY AND SEASONABLE WEDNESDAY. WARMER TEMPERATURES ARRIVE THURSDAY...BEFORE A WET WEATHER SYSTEM CLOSES OUT THE WORK WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 530PM UPDATE...MADE ADJUSTMENTS TO POPS USING CURRENT RADAR PICS AND HRRR DATA. TEMPS WERE ADJUSTED WITH LATEST LAMP GUIDANCE. SHOWERS WILL BE EXITING THE SOUTHEAST SHORTLY AFTER SUNSET AND SKIES WILL CLEAR FROM THE NORTH. PREVIOUS DISCUSSION... SURFACE LOW DROPPING ACROSS WESTERN PA INTO THE APPALACHIANS CURRENTLY...WITH FRONTAL BOUNDARY RECENTLY PASSING THROUGH PIT. STEADIER PRECIP HAS MOVED OFF TO THE EAST...BUT SOME SCATTERED POST-FRONTAL SHRA ARE FIRING IN MODEST INSTABILITY. EXPECT THESE TO PROGRESS TO THE SOUTH AND EAST WITH THE FRONT OVER THE NEXT FEW HOURS. KEPT THE THUNDER CHANCES GOING IN THE SOUTHEAST BEFORE SUNSET...WHERE MORE SUN HAS BEEN SEEN TODAY. ONLY EXPECT A FEW LINGERING SHRA AROUND 00Z IN THE SOUTHEAST BEFORE ENDING DURING THE EVENING. 25-35 MPH WIND GUSTS WILL DIMINISH DURING THAT TIME AS WELL. BAND OF POST-FRONTAL LOW CLOUDS WILL SWING THROUGH DURING THE EVENING AS WELL. A SHORT PERIOD OF PARTIAL CLEARING WILL OCCUR DURING THE PREDAWN HOURS. THEN...ANOTHER WEAK DISTURBANCE CURRENTLY IN MICHIGAN YOOPER COUNTRY WILL APPROACH FROM THE NORTHWEST AROUND 12Z. EXPECT THIS TO MANIFEST MAINLY IN THE FORM OF REINFORCED CLOUD COVER...BUT THERE MAY BE JUST ENOUGH JUICE TO GET A FEW FLURRIES OR LIGHT SNOW SHOWERS NORTH OF I-80 BY SUNRISE. PREVIOUS LOW TEMPERATURE FORECAST WAS AT THE LOWER END OF THE GUIDANCE ENVELOPE. CONSIDERING THE WIND AND EXPECTED CLOUDS...RAISED TEMPERATURES MORE TOWARDS THE MEAN OF THE GUIDANCE. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... BEYOND MAYBE A FEW FLURRIES AND SOME CLOUD COVER ASSOCIATED WITH THE WEAKENING UPPER LEVEL DISTURBANCE AS IT PASSES JUST NORTH OF THE REGION EARLY WEDNESDAY....EXPECT CLEARING SKIES AND NEAR NORMAL TEMPERATURES AS SURFACE RIDGE BUILDS OVERHEAD. WIND SHIFT TO THE SW IS NOT ANTICIPATED UNTIL LATE WEDNESDAY AND WHILE RIDGE WILL BE SHIFTING TO THE EAST...THINK THAT MUCH OF THE REGION WILL BE ALLOWED TO DECOUPLE. THUS...OPTED TO STAY CLOSER TO THE MOS/ECMWF VALUES AND NOT THE WARMER NAME TEMPS. COLD FRONT WILL BE SLOW TO MAKE IT`S APPROACH THURSDAY...WITH STRONG SOUTHWESTERLY WINDS EXPECTED OUT AHEAD OF IT. THIS SHOULD...DESPITE INCREASING CLOUD COVER...BRINGING TEMPERATURES WELL INTO THE 60`S AND LOWER 70`S ACROSS THE REGION AS 850HPA TEMPS APPROACH +10C. PRECIPITATION CONTINUES TO SLOW WITH THE BOUNDARY SO VERY LOW POPS WERE KEPT IN THE FORECAST UNTIL LATE. HOWEVER...THE NAM AND TO A LESSER DEGREE THE ECMWF...SUGGEST AN AREA OF MOISTURE MAY BE ADVECTED NORTHWARD OUT AHEAD OF THE FRONT...BRINGING A CHANCE FOR RAIN TO SOME OF THE REGION BY THURSDAY AFTERNOON. WITH LOW CONFIDENCE ON THE PLACEMENT AND DEVELOPMENT OF THESE SHOWERS...THOUGHT IT BEST TO JUST KEEP POPS LOW FOR NOW. VERY STRONG SOUTHWESTERLY LOW LEVEL JET WILL RESULT IN GUSTY WINDS OF 20-30 MPH THURSDAY AND A CHANCE OF THUNDER MAY BE POSSIBLE LATE WITH THIN CAPE SUGGESTED ON MODEL SOUNDINGS. COLD FRONT WILL REMAIN JUST NORTH OF THE FORECAST AREA UNTIL LATE FRIDAY WHEN A UPPER WAVE AND ITS ASSOCIATED SURFACE LOW DEVELOP AND MOVE ACROSS THE UPPER OHIO VALLEY. STILL SOME UNCERTAINTY ON THE STRENGTH OF THIS LOW AND PLACEMENT BUT LIKELY TO LOW-CATEGORICAL POPS WERE MAINTAINED THROUGH THE PERIOD. TEMPERATURES SHOULD REMAIN ELEVATED UNTIL THE COLD FRONT PASSES LATE FRIDAY...BUT PRECIPITATION WILL KEEP HIGHS FROM BEING AS WARM AS THEY WERE ON THURSDAY. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A DRYING TREND IS INDICATED FOR THE WEEKEND ALTHOUGH A TRAILING SHORTWAVE MAY GENERATE SOME SHOWERS ON SATURDAY. THE COOL DOWN WILL NOT BE SIGNIFICANT THOUGH AS FLAT RIDGING IS ECMWF AND GFS PROGGED TO BUILD AND MODERATE TEMPS FOR NEXT WEEK. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... SCT MVFR CIGS IN COLD ADVECTION BEING SWEPT SOUTHEAST AS SURFACE RIDGE AXIS AND SUBSIDENCE ARE CLEARING SKIES ACROSS NORTHWEST PA. GENERAL VFR EXPECTED AT ALL PORTS BY 02-03Z. WINDS WILL QUICKLY DIMINISH AS WELL WITH LIGHT NORTH WINDS OVERNIGHT. WEAK SHORTWAVE WILL BRING SOME MID DECK TOWARD 12Z WEDNESDAY MAINLY KPIT NORTH. .OUTLOOK.../WEDNESDAY NIGHT THROUGH SUNDAY/... RESTRICTIONS POSSIBLE WITH LOW PRESSURE LATER THURSDAY INTO THE FIRST HALF OF SATURDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
522 PM EDT TUE MAR 31 2015 .SYNOPSIS... HIGH PRESSURE PROVIDES A MAINLY DRY AND SEASONABLE WEDNESDAY. WARMER TEMPERATURES ARRIVE THURSDAY...BEFORE A WET WEATHER SYSTEM CLOSES OUT THE WORK WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 530PM UPDATE...MADE ADJUSTMENTS TO POPS USING CURRENT RADAR PICS AND HRRR DATA. TEMPS WERE ADJUSTED WITH LATEST LAMP GUIDANCE. SHOWERS WILL BE EXITING THE SOUTHEAST SHORTLY AFTER SUNSET AND SKIES WILL CLEAR FROM THE NORTH. PREVIOUS DISCUSSION... SURFACE LOW DROPPING ACROSS WESTERN PA INTO THE APPALACHIANS CURRENTLY...WITH FRONTAL BOUNDARY RECENTLY PASSING THROUGH PIT. STEADIER PRECIP HAS MOVED OFF TO THE EAST...BUT SOME SCATTERED POST-FRONTAL SHRA ARE FIRING IN MODEST INSTABILITY. EXPECT THESE TO PROGRESS TO THE SOUTH AND EAST WITH THE FRONT OVER THE NEXT FEW HOURS. KEPT THE THUNDER CHANCES GOING IN THE SOUTHEAST BEFORE SUNSET...WHERE MORE SUN HAS BEEN SEEN TODAY. ONLY EXPECT A FEW LINGERING SHRA AROUND 00Z IN THE SOUTHEAST BEFORE ENDING DURING THE EVENING. 25-35 MPH WIND GUSTS WILL DIMINISH DURING THAT TIME AS WELL. BAND OF POST-FRONTAL LOW CLOUDS WILL SWING THROUGH DURING THE EVENING AS WELL. A SHORT PERIOD OF PARTIAL CLEARING WILL OCCUR DURING THE PREDAWN HOURS. THEN...ANOTHER WEAK DISTURBANCE CURRENTLY IN MICHIGAN YOOPER COUNTRY WILL APPROACH FROM THE NORTHWEST AROUND 12Z. EXPECT THIS TO MANIFEST MAINLY IN THE FORM OF REINFORCED CLOUD COVER...BUT THERE MAY BE JUST ENOUGH JUICE TO GET A FEW FLURRIES OR LIGHT SNOW SHOWERS NORTH OF I-80 BY SUNRISE. PREVIOUS LOW TEMPERATURE FORECAST WAS AT THE LOWER END OF THE GUIDANCE ENVELOPE. CONSIDERING THE WIND AND EXPECTED CLOUDS...RAISED TEMPERATURES MORE TOWARDS THE MEAN OF THE GUIDANCE. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... BEYOND MAYBE A FEW FLURRIES AND SOME CLOUD COVER ASSOCIATED WITH THE WEAKENING UPPER LEVEL DISTURBANCE AS IT PASSES JUST NORTH OF THE REGION EARLY WEDNESDAY....EXPECT CLEARING SKIES AND NEAR NORMAL TEMPERATURES AS SURFACE RIDGE BUILDS OVERHEAD. WIND SHIFT TO THE SW IS NOT ANTICIPATED UNTIL LATE WEDNESDAY AND WHILE RIDGE WILL BE SHIFTING TO THE EAST...THINK THAT MUCH OF THE REGION WILL BE ALLOWED TO DECOUPLE. THUS...OPTED TO STAY CLOSER TO THE MOS/ECMWF VALUES AND NOT THE WARMER NAME TEMPS. COLD FRONT WILL BE SLOW TO MAKE IT`S APPROACH THURSDAY...WITH STRONG SOUTHWESTERLY WINDS EXPECTED OUT AHEAD OF IT. THIS SHOULD...DESPITE INCREASING CLOUD COVER...BRINGING TEMPERATURES WELL INTO THE 60`S AND LOWER 70`S ACROSS THE REGION AS 850HPA TEMPS APPROACH +10C. PRECIPITATION CONTINUES TO SLOW WITH THE BOUNDARY SO VERY LOW POPS WERE KEPT IN THE FORECAST UNTIL LATE. HOWEVER...THE NAM AND TO A LESSER DEGREE THE ECMWF...SUGGEST AN AREA OF MOISTURE MAY BE ADVECTED NORTHWARD OUT AHEAD OF THE FRONT...BRINGING A CHANCE FOR RAIN TO SOME OF THE REGION BY THURSDAY AFTERNOON. WITH LOW CONFIDENCE ON THE PLACEMENT AND DEVELOPMENT OF THESE SHOWERS...THOUGHT IT BEST TO JUST KEEP POPS LOW FOR NOW. VERY STRONG SOUTHWESTERLY LOW LEVEL JET WILL RESULT IN GUSTY WINDS OF 20-30 MPH THURSDAY AND A CHANCE OF THUNDER MAY BE POSSIBLE LATE WITH THIN CAPE SUGGESTED ON MODEL SOUNDINGS. COLD FRONT WILL REMAIN JUST NORTH OF THE FORECAST AREA UNTIL LATE FRIDAY WHEN A UPPER WAVE AND ITS ASSOCIATED SURFACE LOW DEVELOP AND MOVE ACROSS THE UPPER OHIO VALLEY. STILL SOME UNCERTAINTY ON THE STRENGTH OF THIS LOW AND PLACEMENT BUT LIKELY TO LOW-CATEGORICAL POPS WERE MAINTAINED THROUGH THE PERIOD. TEMPERATURES SHOULD REMAIN ELEVATED UNTIL THE COLD FRONT PASSES LATE FRIDAY...BUT PRECIPITATION WILL KEEP HIGHS FROM BEING AS WARM AS THEY WERE ON THURSDAY. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A DRYING TREND IS INDICATED FOR THE WEEKEND ALTHOUGH A TRAILING SHORTWAVE MAY GENERATE SOME SHOWERS ON SATURDAY. THE COOL DOWN WILL NOT BE SIGNIFICANT THOUGH AS FLAT RIDGING IS ECMWF AND GFS PROGGED TO BUILD AND MODERATE TEMPS FOR NEXT WEEK. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... FKL/DUJ REMAIN AT IFR/LIFR IN THE COLDER AIRMASS. EXPECT SOME IMPROVEMENT BY 21Z OR THEREAFTER AS DRIER AIR WORKS IN FROM THE NORTH. SOME SCATTERED SHRA ARE ALSO OCCURRING BEHIND THE FRONT AND WILL CONTINUE THROUGH SUNSET. CANNOT RULE OUT AN ISOLATED THUNDERSTORM NEAR LBE/MGW BEFORE 00Z...BUT CHANCES TOO LOW TO INCLUDE IN TAF. OTHER SITES AT VFR CURRENTLY...BUT EXPECT A PERIOD OF MVFR CIGS FROM LATE AFTERNOON INTO THE EVENING IN POST-FRONTAL LOW CLOUDS IN COLD ADVECTION PATTERN. CIGS WILL THEN LIFT BACK TO MVFR DURING THE NIGHT...WITH A PERIOD OF MAINLY SCT CLOUD COVERAGE. HOWEVER...WEAK SYSTEM DROPPING IN FROM THE NORTHWEST SHOULD REESTABLISH SOME CLOUD COVER ACROSS WESTERN PA/NORTHERN WV AFTER 10Z. EXPECTING CIGS TO REMAIN VFR AT THIS TIME...WITH POSSIBLY A FEW ISOLATED SHSN. .OUTLOOK.../WEDNESDAY THROUGH SATURDAY/... MORE RESTRICTIONS ARE LIKELY WITH THE CROSSING OF LOW PRESSURE ON LATE THURSDAY AND FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
923 AM EDT TUE MAR 31 2015 .SYNOPSIS... LOW PRESSURE TRACKING ACROSS THE REGION TODAY WILL BRING ANOTHER ROUND OF PRECIPITATION. WARMER TEMPERATURES WILL ARRIVE FOR THE END OF THE WORK WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 920 AM...CONTINUED PREVIOUS TREND OF MOVING LIKELY/CAT POPS A BIT FURTHER NORTH GIVEN RAP/HRRR RUNS AND RADAR TRENDS. RAIN/SNOW LINE IS HOLDING NORTH AS EXPECTED. DID NOT SIGNFICANTLY ALTER SNOW EXPECTATIONS. TWEAKS ELSEWHERE. WITH 530AM UPDATE...HAVE EDGED GRADIENT FOR PRECIPITATION CHANCES SLIGHTLY FARTHER TO THE NORTH. ALTHOUGH INITIAL BAND OF PRECIPITATION CURRENTLY EXTENDS FROM PITTSBURGH TO THE NORTH...BROADER SHIELD OF PRECIPITATION STILL REMAINS MOSTLY OVER MICHIGAN AND LAKE ERIE. 06Z NAM AND 07Z HRRR ALSO SHOW THIS CONTINUED SHIFT TO THE NORTH. IF THESE MODEL RUNS VERIFY...THEN FORECAST OF LIKELY/CATEGORICAL POPS MAY STILL BE TOO FAR TO THE SOUTH. PREVIOUS DISCUSSION FOLLOWS. LOW PRESSURE WILL MOVE THROUGH THE REGION TODAY. SO FAR OVERNIGHT THE TRACK OF THE LOW APPEARS TO BE SLIGHTLY FARTHER NORTH THAN SYNOPTIC MODELS HAVE IN THE FORECAST. IMPLICATION WITH THE JOG TO THE NORTH IS THAT WARMER AIR WILL BE PULLED SLIGHTLY FARTHER NORTH...WHICH SHOULD REDUCE THE AREAL COVERAGE OF SNOWFALL IN OUR AREA. IN ADDITION...THIS SHOULD ALSO SHIFT THE AXIS OF HEAVIEST PRECIPITATION SLIGHTLY FARTHER TO THE NORTH AS WELL...CLOSER TO THE NEW YORK/PENNSYLVANIA STATE LINE. FINALLY...THINK THAT MODELS ONCE AGAIN ARE OVERDOING OVERALL LIFT IN THE STORM...WHICH IS LIKELY CRANKING OUT TOO MUCH PRECIPITATION. IN THE END...DID NOT MAKE ANY MAJOR CHANGES TO TODAYS FORECAST...WITH THE EXCEPTION OF SLIGHTLY LOWERING SNOWFALL TOTALS WHERE SNOWFALL WILL OCCUR. AS THE LOW TRACKS FARTHER TO THE EAST...CANNOT RULE OUT THE SLIGHT CHANCE OF A THUNDERSTORM SOUTH OF INTERSTATE 70 LATER THIS AFTERNOON AS SOME MODEST INSTABILITY WILL BE PRESENT. THE PASSAGE OF THE COLD FRONT WILL ALSO BRING IN GUSTY WINDS...ESPECIALLY IN THE RIDGES WHERE 40-45 MPH WIND GUSTS WILL BE POSSIBLE. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... A PASSING RAIN SHOWER WILL BE POSSIBLE ACROSS THE SOUTHEAST THIS EVENING...BUT ALL PRECIPITATION WILL COME TO AN END BY MIDNIGHT. A NEW WRINKLE TO THE FORECAST LATER TONIGHT INTO WEDNESDAY IS A WEAK LOW PRESSURE SYSTEM THAT SHOULD TRACK NORTHEAST OF PITTSBURGH. MODELS WERE NOT PICKING UP ON THIS FEATURE 24 HOURS AGO...BUT THE SYSTEM IS CURRENTLY PRODUCING PRECIPITATION ACROSS CANADA. DID NOT HAVE ENOUGH CONFIDENCE TO ADD ANY SNOW SHOWERS TO THE FORECAST...AS ALL LOCATIONS SHOULD DROP BELOW FREEZING OVERNIGHT...BUT HAVE BUMPED UP CLOUD COVER LATE TONIGHT INTO WEDNESDAY MORNING. SKIES SHOULD THEN CLEAR UP WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING. THE CLEAR SKIES WILL BE SHORT LIVED AS CLOUDS BEGIN TO INCREASE AGAIN IN ADVANCE OF THE NEXT COLD FRONT APPROACHING THE REGION. STRONG SOUTHWESTERLY WIND WILL RESULT IN GUSTY WINDS OF 20-30 MPH THURSDAY...BUT WILL ALSO RAISE TEMPERATURES INTO THE 60S AND 70S. CHANCES FOR RAIN WILL BE ON THE INCREASE DURING THE DAY...AND HAVE ALSO ADDED THUNDER TO THE FORECAST AS WELL. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... DECENT PRECIPITATION CHANCES WILL CONTINUE INTO THE WEEKEND AS THE FRONT SAGS ACROSS THE REGION AND PROVIDES FOCUS FOR SUBSEQUENT LOW PRESSURE PASSAGE LATER ON FRIDAY...WITH AN EASTWARD EXIT ON SATURDAY. CHANGES INCLUDE A UPWARD POP ADJUSTMENT TO CATEGORICAL NUMBERS FOR THURSDAY NIGHT...AND FOR SOUTHERN COUNTIES ON FRIDAY. A DRYING TREND IS INDICATED FOR THE WEEKEND ALTHOUGH A TRAILING SHORTWAVE MAY GENERATE SOME SHOWERS ON SATURDAY. THE COOL DOWN WILL NOT BE SIGNIFICANT THOUGH AS FLAT RIDGING IS ECMWF AND GFS PROGGED TO BUILD AND MODERATE TEMPS FOR NEXT WEEK. && .AVIATION /13Z TUESDAY THROUGH SATURDAY/... CONDITION DETERIORATION IS EXPECTED THIS MORNING WITH IFR AT FKL AND DUJ AS LOW PRESSURE SPREADS RAIN AND SNOW OVER THE AREA. OTHERWISE...GENERAL MVFR WITH RAIN IS ANTICIPATED FOR PORTS SURROUNDING THE PIT AREA. AS THE LOW CROSSES AROUND MID DAY AND AS SURFACE WARMING AND COOLING ALOFT INCREASE THE DEPTH OF THE MIXING LAYER...SURFACE WIND GUSTS WILL INCREASE TO AROUND 25 KTS WITH A DIRECTION VEER TO THE NORTH...NORTHWEST. MVFR STRATOCU ARE EXPECTED TO PERSIST INTO TUESDAY EVE AS COLD ADVECTION ENSUES IN THE WAKE OF THE RAPIDLY EXITING SYSTEM. .OUTLOOK.../WEDNESDAY THROUGH SATURDAY/... MORE RESTRICTIONS ARE LIKELY WITH THE CROSSING OF LOW PRESSURE ON LATE THURSDAY AND FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
525 AM EDT TUE MAR 31 2015 .SYNOPSIS... LOW PRESSURE TRACKING ACROSS THE REGION TODAY WILL BRING ANOTHER ROUND OF PRECIPITATION. WARMER TEMPERATURES WILL ARRIVE FOR THE END OF THE WORK WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH 530AM UPDATE...HAVE EDGED GRADIENT FOR PRECIPITATION CHANCES SLIGHTLY FARTHER TO THE NORTH. ALTHOUGH INITIAL BAND OF PRECIPITATION CURRENTLY EXTENDS FROM PITTSBURGH TO THE NORTH...BROADER SHIELD OF PRECIPITATION STILL REMAINS MOSTLY OVER MICHIGAN AND LAKE ERIE. 06Z NAM AND 07Z HRRR ALSO SHOW THIS CONTINUED SHIFT TO THE NORTH. IF THESE MODEL RUNS VERIFY...THEN FORECAST OF LIKELY/CATEGORICAL POPS MAY STILL BE TOO FAR TO THE SOUTH. PREVIOUS DISCUSSION FOLLOWS. LOW PRESSURE WILL MOVE THROUGH THE REGION TODAY. SO FAR OVERNIGHT THE TRACK OF THE LOW APPEARS TO BE SLIGHTLY FARTHER NORTH THAN SYNOPTIC MODELS HAVE IN THE FORECAST. IMPLICATION WITH THE JOG TO THE NORTH IS THAT WARMER AIR WILL BE PULLED SLIGHTLY FARTHER NORTH...WHICH SHOULD REDUCE THE AREAL COVERAGE OF SNOWFALL IN OUR AREA. IN ADDITION...THIS SHOULD ALSO SHIFT THE AXIS OF HEAVIEST PRECIPITATION SLIGHTLY FARTHER TO THE NORTH AS WELL...CLOSER TO THE NEW YORK/PENNSYLVANIA STATE LINE. FINALLY...THINK THAT MODELS ONCE AGAIN ARE OVERDOING OVERALL LIFT IN THE STORM...WHICH IS LIKELY CRANKING OUT TOO MUCH PRECIPITATION. IN THE END...DID NOT MAKE ANY MAJOR CHANGES TO TODAYS FORECAST...WITH THE EXCEPTION OF SLIGHTLY LOWERING SNOWFALL TOTALS WHERE SNOWFALL WILL OCCUR. AS THE LOW TRACKS FARTHER TO THE EAST...CANNOT RULE OUT THE SLIGHT CHANCE OF A THUNDERSTORM SOUTH OF INTERSTATE 70 LATER THIS AFTERNOON AS SOME MODEST INSTABILITY WILL BE PRESENT. THE PASSAGE OF THE COLD FRONT WILL ALSO BRING IN GUSTY WINDS...ESPECIALLY IN THE RIDGES WHERE 40-45 MPH WIND GUSTS WILL BE POSSIBLE. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... A PASSING RAIN SHOWER WILL BE POSSIBLE ACROSS THE SOUTHEAST THIS EVENING...BUT ALL PRECIPITATION WILL COME TO AN END BY MIDNIGHT. A NEW WRINKLE TO THE FORECAST LATER TONIGHT INTO WEDNESDAY IS A WEAK LOW PRESSURE SYSTEM THAT SHOULD TRACK NORTHEAST OF PITTSBURGH. MODELS WERE NOT PICKING UP ON THIS FEATURE 24 HOURS AGO...BUT THE SYSTEM IS CURRENTLY PRODUCING PRECIPITATION ACROSS CANADA. DID NOT HAVE ENOUGH CONFIDENCE TO ADD ANY SNOW SHOWERS TO THE FORECAST...AS ALL LOCATIONS SHOULD DROP BELOW FREEZING OVERNIGHT...BUT HAVE BUMPED UP CLOUD COVER LATE TONIGHT INTO WEDNESDAY MORNING. SKIES SHOULD THEN CLEAR UP WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING. THE CLEAR SKIES WILL BE SHORT LIVED AS CLOUDS BEGIN TO INCREASE AGAIN IN ADVANCE OF THE NEXT COLD FRONT APPROACHING THE REGION. STRONG SOUTHWESTERLY WIND WILL RESULT IN GUSTY WINDS OF 20-30 MPH THURSDAY...BUT WILL ALSO RAISE TEMPERATURES INTO THE 60S AND 70S. CHANCES FOR RAIN WILL BE ON THE INCREASE DURING THE DAY...AND HAVE ALSO ADDED THUNDER TO THE FORECAST AS WELL. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... DECENT PRECIPITATION CHANCES WILL CONTINUE INTO THE WEEKEND AS THE FRONT SAGS ACROSS THE REGION AND PROVIDES FOCUS FOR SUBSEQUENT LOW PRESSURE PASSAGE LATER ON FRIDAY...WITH AN EASTWARD EXIT ON SATURDAY. CHANGES INCLUDE A UPWARD POP ADJUSTMENT TO CATEGORICAL NUMBERS FOR THURSDAY NIGHT...AND FOR SOUTHERN COUNTIES ON FRIDAY. A DRYING TREND IS INDICATED FOR THE WEEKEND ALTHOUGH A TRAILING SHORTWAVE MAY GENERATE SOME SHOWERS ON SATURDAY. THE COOL DOWN WILL NOT BE SIGNIFICANT THOUGH AS FLAT RIDGING IS ECMWF AND GFS PROGGED TO BUILD AND MODERATE TEMPS FOR NEXT WEEK. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... CONDITION DETERIORATION IS EXPECTED THIS MORNING WITH IFR AT FKL AND DUJ AS LOW PRESSURE SPREADS RAIN AND SNOW OVER THE AREA. OTHERWISE...GENERAL MVFR WITH RAIN IS ANTICIPATED FOR PORTS SURROUNDING THE PIT AREA. AS THE LOW CROSSES AROUND MID DAY AND AS SURFACE WARMING AND COOLING ALOFT INCREASE THE DEPTH OF THE MIXING LAYER...SURFACE WIND GUSTS WILL INCREASE TO AROUND 25 KTS WITH A DIRECTION VEER TO THE NORTH...NORTHWEST. MVFR STRATOCU ARE EXPECTED TO PERSIST INTO TUESDAY EVE AS COLD ADVECTION ENSUES IN THE WAKE OF THE RAPIDLY EXITING SYSTEM. .OUTLOOK.../WEDNESDAY THROUGH SATURDAY/... MORE RESTRICTIONS ARE LIKELY WITH THE CROSSING OF LOW PRESSURE ON LATE THURSDAY AND FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
415 PM EDT TUE MAR 31 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 414 PM EDT TUE MAR 31 2015 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BTWN A TROUGH OVER ERN CANADA AND A RIDGE FROM THE SW CONUS INTO THE CANADIAN ROCKIES. A SHORTWAVE MOVING THROUGH THE NRN GREAT LAKES HAS SUPPORTED PCPN MAINLY IN THE FORM OF LIGHT SNOW ACROSS THE NRN TIER OF UPPER MI. CLOUDS ASSOC WITH THE SHORTWAVE HAVE SPREAD ACROSS MUCH OF THE CWA THIS AFTERNOON AND HIGH TEMPS TODAY HAVE RANGED FM THE 30S NORTH AND FAR EAST TO GENERALLY THE 40S ELSEWHERE. TONIGHT...ANY LINGERING SNOW OVER THE EAST HALF SHOULD DIMINISH DURING THE EVENING AS THE SHRTWV DEPARTS TO THE SE. THERE IS SOME UNCERTAINTY AS TO THE AMOUNT/DEPTH OF LOW LEVEL MOISTURE LINGERING BEHIND THE SYSTEM AS A WEAK SFC RIDGE BUILDS INTO THE AREA. SOME OF MODELS SUGGEST LOW-LVL MOISTURE COULD LINGER NCNTRL AND EAST AND FOR THOSE AREAS FAVORED BY UPSLOPE NE-E FLOW. UNDER PARTLY TO MOSTLY CLOUDY SKIES EXPECT TEMPS TO DROP INTO THE LOWER TO MID 20S MOST PLACES. WEDNESDAY...AS SHORTWAVE ENERGY NOW OVER THE PAC NW BEGINS TO DRIVE INTO THE BACKSIDE OF THE MID-LVL RIDGE ON WEDNESDAY INCREASING WAA/ISENTROPIC ASCENT WL SPREAD INTO UPPER MI LATE TONIGHT INTO WEDNESDAY. LOWERING CONDENSATION PRES DEFICITS AND MODEL SNDGS SUGGEST BEST CHC OF PCPN WL BE OVER THE NRN TIER IN THE MORNING AND ERN PORTION OF CWA IN THE AFTERNOON SO WILL KEEP HIGHER CHC POPS OVER THESE COUNTIES. MODEL SNDGS LOOK FAIRLY DRY TO THE SOUTH AND SOUTHWEST SO NOT EXPECTING MUCH IF ANY PCPN THERE UNTIL LATE IN AFTERNOON WHEN SFC TROF APPROACHES FM WEST. SOME ELEVATED CAPE VALUES APPROACHING 250-500 J/KG COULD MAYBE EVEN RESULT IN SOME ISOLD TS LATE WED AFTERNOON INTO EVENING SO WL KEEP IN SLIGHT CHC FOR THUNDER FOR FAR WEST. HIGH TEMPS UNDER STRENGTHENING SOUTHEAST FLOW WILL RANGE FROM THE 40S EAST HALF AND OVER THE KEWEENAW TO THE UPPER 50S FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR FAR WEST. SSE WINDS WILL ALSO LIKELY GUST OVER 30 MPH FOR SOME DOWNSLOPING LOCATIONS ALONG LAKE SUPERIOR OVER THE WEST HALF AND OVER THE TIP OF THE KEWEENAW PENINSULA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 334 PM EDT TUE MAR 31 2015 THE UPPER TROUGH THAT IS CURRENTLY MOVING ONSHORE OVER THE PACIFIC NORTHWEST WILL MOVING THROUGH NORTH DAKOTA AND SOUTHERN SASKATCHEWAN AT THE START OF THE PERIOD. AHEAD OF THIS WAVE...BROAD MID LEVEL WARM AIR ADVECTION WILL BE PRODUCING LIGHT PRECIPITATION (THROUGH SIGNIFICANT DRY AIR BELOW 700MB) AT THE START OF THE PERIOD...BUT IT WILL BE SHIFTING TO THE EAST DURING THE EVENING. MEANWHILE...THE MAIN SURFACE LOW WILL BE BACK IN SOUTHERN SASKATCHEWAN WHILE A TROUGH STRETCHES EAST-SOUTHEAST THROUGH NORTHERN MINNESOTA AND THEN SOUTH INTO IOWA. THIS TROUGH WILL BE THE FOCUS OF THE RAIN CHANCES WEDNESDAY NIGHT INTO THURSDAY MORNING AS IT MOVES ACROSS UPPER MICHIGAN. EXPECT SHOWERS AND THUNDERSTORMS TO FIRE ALONG THIS FRONT WEDNESDAY AFTERNOON FROM CENTRAL MINNESOTA THROUGH IOWA AND THEN QUICKLY MOVE NORTHEAST TOWARDS THE AREA AS THE TROUGH SHIFTS EAST AND WEAKENS. THAT WEAKENING OF THE TROUGH AS IT MOVES THROUGH THE CWA IS A LITTLE CONCERNING...SINCE IT WILL LEAD TO MORE SCATTERED SHOWERS THAN A WIDESPREAD RAIN...ESPECIALLY WITH THE UPSTREAM SHOWERS/THUNDERSTORMS FEEDING OFF THE BETTER MOISTURE/INSTABILITY TRYING TO MOVE INTO THE AREA. WILL CONTINUE TO SHOW CHANCE POPS SHIFTING EAST ACROSS THE CWA WEDNESDAY NIGHT...WITH LIKELY VALUES OVER THE EAST WITH THE DEPARTING WARM AIR ADVECTION AND ALONG THE WISCONSIN BORDER WITH THE BETTER OPPORTUNITY TO SEE THE SHOWERS/THUNDERSTORMS REACHING THAT AREA. WILL CONTINUE TO INCLUDE THUNDER ALONG THE WISCONSIN BORDER...AS THAT AREA WOULD HAVE THE BEST OPPORTUNITY OF THUNDERSTORMS MOVING NORTHEAST INTO THE CWA FROM THE CONVECTION TIED TO THE DIMINISHING INSTABILITY THROUGH THE NIGHT. AS THIS TROUGH SHIFTS THROUGH THE EASTERN U.P. ON THURSDAY MORNING...WILL SHOW LINGERING SHOWERS IN THAT AREA BEFORE QUICKLY ENDING AS THE DRY SLOT MOVES OVER UPPER MICHIGAN. THIS DRY SLOT WILL LEAD TO A DECREASING CLOUDS AND A WARM DAY ACROSS THE U.P. UNDER GUSTY WESTERLY WINDS. WITH TEMPERATURES WARMING THROUGH THE NIGHT ON WEDNESDAY NIGHT...WILL HAVE A WARM START TO THE DAY AND THE INCREASING SUNSHINE WILL ALLOW HIGHS TO RISE INTO THE 50S FOR MOST LOCATIONS AND EVEN SOME LOW 60S FOR THE DOWNSLOPE AREAS OF THE SOUTH CENTRAL CWA. FOR LOCATIONS WITHOUT SNOW...ESPECIALLY OVER THE SOUTH CENTRAL...THE PATTERN IS FAVORABLE FOR FIRES (LOW TO THE NORTH...GUSTY WESTERLY WINDS...AND DRY LOW LEVEL AIR). HOPEFULLY...ANY OPEN DEBRIS BURNING WILL BE LIMITED AND CAREFULLY TENDED OVER THE SOUTH CENTRAL AS CONDITIONS ARE SUPPORTIVE FOR FIRE SPREADING (ESPECIALLY IF RAINFALL THE NIGHT BEFORE IS LIMITED). THE WARM AIR WILL BE SHORT LIVED AS MUCH COLDER AIR SURGES INTO THE AREA THURSDAY NIGHT BEHIND THE TRAILING COLD FRONT. THIS WILL STEADILY DROP TEMPS THROUGH THE NIGHT AND INTO THE 20S BY DAYBREAK FRIDAY...WITH LIKELY ONLY A LIMITED WARM UP INTO THE 30S DURING THE DAY. WITH THIS COLD AIR...MODELS CONTINUE TO SHOW ENOUGH MOISTURE BELOW 800MB FOR CLOUDS AND THERE MAY BE ENOUGH OVER THE LAKE INSTABILITY (850MB TEMPS FALLING TO -11C) TO SUPPORT LAKE CLOUDS OR EVEN SOME TERRAIN ENHANCED SNOW SHOWERS WITH THE NORTHWEST AND EVENTUALLY NORTHERLY WINDS ON FRIDAY. WITH THE DELTA-T VALUES ON THE MARGINAL SIDE...WON/T GO MUCH MORE THAN SLIGHT OR LOW END CHANCE POPS FOR THE FAVORED NORTHWEST WIND UPSLOPE AREAS AFTER MIDNIGHT THURSDAY NIGHT AND THEN GRADUALLY DECREASE THROUGH THE DAY ON FRIDAY WITH THE DRIER AIR QUICKLY ARRIVING AHEAD OF A HIGH IN CENTRAL CANADA. THAT DRY AIR WILL BE SHORT LIVED...AS A WEAK SHORTWAVE AND WEAK SURFACE LOW DIVES SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION LATE FRIDAY NIGHT INTO SATURDAY AND BRINGS A FEW LIGHT SNOW SHOWERS TO THE AREA. WITH LIMITED MOISTURE TO WORK WITH...WILL KEEP ISOLATED SNOW SHOWERS IN THE FORECAST AS IT MOVES THROUGH. AFTER THAT WAVE...INDICATIONS ARE THE REST OF THE WEEKEND WILL BE DRY AS THE HIGH FROM CENTRAL CANADA MOVES THROUGH THE AREA AND THE WISCONSIN BORDER IS BRUSHED BY ANOTHER WAVE ON SUNDAY. WITH THE REGION STILL INFLUENCED BY THE UPPER TROUGH IN EASTERN CANADA...TEMPERATURES WILL REMAIN BELOW NORMAL. SHOULD SEE A GRADUAL MODERATION TO THE TEMPS FOR THE FIRST PART OF NEXT WEEK (BUT STILL REMAINING BELOW NORMAL) AS THE FLOW ALOFT BECOMES WESTERLY AS A UPPER TROUGH AMPLIFIES OVER THE WESTERN CONUS. THIS TROUGH HAS THE POTENTIAL TO PRODUCE A MORE ACTIVE PERIOD OF WEATHER DURING THE MIDDLE OF NEXT WEEK AS DISTURBANCES EJECT EAST-NORTHEAST TOWARDS THE AREA. WILL TREND POPS DOWN ON MONDAY...AS THE LATEST MODELS RUNS ARE PLACING THE WARM FRONT FARTHER SOUTH THAN 24HRS AGO. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 143 PM EDT TUE MAR 31 2015 AN UPPER DISTURBANCE EXITING E OF THE REGION WILL BRING TO AN END SCT -SHSN LATE THIS AFTERNOON AT KCMX AND KSAW. AT KIWD...EXPECT IMPROVEMENT FM MVFR TO VFR ESPECIALLY TOWARD EVENING AS WINDS BECOME LIGHT NE BEHIND THE DISTURBANCE. AT KCMX AND KSAW...EVEN AFTER THE DISTURBANCE MOVES AWAY...SOME LOW CLOUDS/MVFR CIGS MAY LINGER AT LEAST INTO THE EARLY OVERNIGHT TONIGHT UNDER A LOW-LVL E-NE UPSLOPE FLOW AHEAD OF APPROACHING SFC HIGH PRES. EXPECT IMPROVEMENT TO VFR AT KSAW AND KCMX BY LATE WED MORNING WITH INCREASED MIXING AND WINDS BECOMING SE AHEAD OF THE NEXT LOW PRES SYSTEM DEVELOPING OVER THE PLAINS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 413 PM EDT TUE MAR 31 2015 WINDS WILL REMAIN BELOW 25 KNOTS THROUGH MOST OF THE REST OF THE WEEK WITH THE EXCEPTION OF WED AFTERNOON INTO WED EVENING. SOUTH TO SOUTHEAST AE EXPECTED TO INCREASE TO GALES TO 35-40 KTS OVER CENTRAL LAKE SUPERIOR LATE WED AFTERNOON INTO EVENING AHEAD OF A TROUGH MOVING INTO THE WRN GREAT LAKES. THERE COULD BE A FEW GALE FORCE GUSTS ACROSS THE FAR EASTERN END OF LAKE SUPERIOR. WINDS WILL ALSO INCREASE TO NEAR 30 KNOTS THU NIGHT INTO FRIDAY IN THE WAKE OF A COLD FRONT MOVING THROUGH THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 5 PM TO 10 PM EDT WEDNESDAY FOR LSZ244-245. GALE WARNING FROM 5 PM TO 11 PM EDT WEDNESDAY FOR LSZ265. GALE WARNING FROM 5 PM WEDNESDAY TO MIDNIGHT EDT WEDNESDAY NIGHT FOR LSZ264-266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
413 PM EDT TUE MAR 31 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 413 PM EDT TUE MAR 31 2015 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BTWN A TROUGH OVER ERN CANADA AND A RIDGE FROM THE SW CONUS INTO THE CANADIAN ROCKIES. A SHORTWAVE MOVING THROUGH THE NRN GREAT LAKES HAS SUPPORTED PCPN MAINLY IN THE FORM OF LIGHT SNOW ACROSS THE NRN TIER OF UPPER MI. CLOUDS ASSOC WITH THE SHORTWAVE HAVE SPREAD ACROSS MUCH OF THE CWA THIS AFTERNOON AND HIGH TEMPS TODAY HAVE RANGED FM THE 30S NORTH AND FAR EAST TO GENERALLY THE 40S ELSEWHERE. TONIGHT...ANY LINGERING SNOW OVER THE EAST HALF SHOULD DIMINISH DURING THE EVENING AS THE SHRTWV DEPARTS TO THE SE. THERE IS SOME UNCERTAINTY AS TO THE AMOUNT/DEPTH OF LOW LEVEL MOISTURE LINGERING BEHIND THE SYSTEM AS A WEAK SFC RIDGE BUILDS INTO THE AREA. SOME OF MODELS SUGGEST LOW-LVL MOISTURE COULD LINGER NCNTRL AND EAST AND FOR THOSE AREAS FAVORED BY UPSLOPE NE-E FLOW. UNDER PARTLY TO MOSTLY CLOUDY SKIES EXPECT TEMPS TO DROP INTO THE LOWER TO MID 20S MOST PLACES. WEDNESDAY...AS SHORTWAVE ENERGY NOW OVER THE PAC NW BEGINS TO DRIVE INTO THE BACKSIDE OF THE MID-LVL RIDGE ON WEDNESDAY INCREASING WAA/ISENTROPIC ASCENT WL SPREAD INTO UPPER MI LATE TONIGHT INTO WEDNESDAY. LOWERING CONDENSATION PRES DEFICITS AND MODEL SNDGS SUGGEST BEST CHC OF PCPN WL BE OVER THE NRN TIER IN THE MORNING AND ERN PORTION OF CWA IN THE AFTERNOON SO WILL KEEP HIGHER CHC POPS OVER THESE COUNTIES. MODEL SNDGS LOOK FAIRLY DRY TO THE SOUTH AND SOUTHWEST SO NOT EXPECTING MUCH IF ANY PCPN THERE UNTIL LATE IN AFTERNOON WHEN SFC TROF APPROACHES FM WEST. SOME ELEVATED CAPE VALUES APPROACHING 250-500 J/KG COULD MAYBE EVEN RESULT IN SOME ISOLD TS LATE WED AFTERNOON INTO EVENING SO WL KEEP IN SLIGHT CHC FOR THUNDER FOR FAR WEST. HIGH TEMPS UNDER STRENGTHING SOUTHEAST FLOW WILL RANGE FROM THE 40S EAST HALF AND OVER THE KEWEENAW TO THE UPPER 50S FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR FAR WEST. SSE WINDS WILL ALSO LIKELY GUST OVER 30 MPH FOR SOME DOWNSLOPING LOCATIONS ALONG LAKE SUPERIOR OVER THE WEST HALF AND OVER THE TIP OF THE KEWEENAW PENINSULA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 334 PM EDT TUE MAR 31 2015 THE UPPER TROUGH THAT IS CURRENTLY MOVING ONSHORE OVER THE PACIFIC NORTHWEST WILL MOVING THROUGH NORTH DAKOTA AND SOUTHERN SASKATCHEWAN AT THE START OF THE PERIOD. AHEAD OF THIS WAVE...BROAD MID LEVEL WARM AIR ADVECTION WILL BE PRODUCING LIGHT PRECIPITATION (THROUGH SIGNIFICANT DRY AIR BELOW 700MB) AT THE START OF THE PERIOD...BUT IT WILL BE SHIFTING TO THE EAST DURING THE EVENING. MEANWHILE...THE MAIN SURFACE LOW WILL BE BACK IN SOUTHERN SASKATCHEWAN WHILE A TROUGH STRETCHES EAST-SOUTHEAST THROUGH NORTHERN MINNESOTA AND THEN SOUTH INTO IOWA. THIS TROUGH WILL BE THE FOCUS OF THE RAIN CHANCES WEDNESDAY NIGHT INTO THURSDAY MORNING AS IT MOVES ACROSS UPPER MICHIGAN. EXPECT SHOWERS AND THUNDERSTORMS TO FIRE ALONG THIS FRONT WEDNESDAY AFTERNOON FROM CENTRAL MINNESOTA THROUGH IOWA AND THEN QUICKLY MOVE NORTHEAST TOWARDS THE AREA AS THE TROUGH SHIFTS EAST AND WEAKENS. THAT WEAKENING OF THE TROUGH AS IT MOVES THROUGH THE CWA IS A LITTLE CONCERNING...SINCE IT WILL LEAD TO MORE SCATTERED SHOWERS THAN A WIDESPREAD RAIN...ESPECIALLY WITH THE UPSTREAM SHOWERS/THUNDERSTORMS FEEDING OFF THE BETTER MOISTURE/INSTABILITY TRYING TO MOVE INTO THE AREA. WILL CONTINUE TO SHOW CHANCE POPS SHIFTING EAST ACROSS THE CWA WEDNESDAY NIGHT...WITH LIKELY VALUES OVER THE EAST WITH THE DEPARTING WARM AIR ADVECTION AND ALONG THE WISCONSIN BORDER WITH THE BETTER OPPORTUNITY TO SEE THE SHOWERS/THUNDERSTORMS REACHING THAT AREA. WILL CONTINUE TO INCLUDE THUNDER ALONG THE WISCONSIN BORDER...AS THAT AREA WOULD HAVE THE BEST OPPORTUNITY OF THUNDERSTORMS MOVING NORTHEAST INTO THE CWA FROM THE CONVECTION TIED TO THE DIMINISHING INSTABILITY THROUGH THE NIGHT. AS THIS TROUGH SHIFTS THROUGH THE EASTERN U.P. ON THURSDAY MORNING...WILL SHOW LINGERING SHOWERS IN THAT AREA BEFORE QUICKLY ENDING AS THE DRY SLOT MOVES OVER UPPER MICHIGAN. THIS DRY SLOT WILL LEAD TO A DECREASING CLOUDS AND A WARM DAY ACROSS THE U.P. UNDER GUSTY WESTERLY WINDS. WITH TEMPERATURES WARMING THROUGH THE NIGHT ON WEDNESDAY NIGHT...WILL HAVE A WARM START TO THE DAY AND THE INCREASING SUNSHINE WILL ALLOW HIGHS TO RISE INTO THE 50S FOR MOST LOCATIONS AND EVEN SOME LOW 60S FOR THE DOWNSLOPE AREAS OF THE SOUTH CENTRAL CWA. FOR LOCATIONS WITHOUT SNOW...ESPECIALLY OVER THE SOUTH CENTRAL...THE PATTERN IS FAVORABLE FOR FIRES (LOW TO THE NORTH...GUSTY WESTERLY WINDS...AND DRY LOW LEVEL AIR). HOPEFULLY...ANY OPEN DEBRIS BURNING WILL BE LIMITED AND CAREFULLY TENDED OVER THE SOUTH CENTRAL AS CONDITIONS ARE SUPPORTIVE FOR FIRE SPREADING (ESPECIALLY IF RAINFALL THE NIGHT BEFORE IS LIMITED). THE WARM AIR WILL BE SHORT LIVED AS MUCH COLDER AIR SURGES INTO THE AREA THURSDAY NIGHT BEHIND THE TRAILING COLD FRONT. THIS WILL STEADILY DROP TEMPS THROUGH THE NIGHT AND INTO THE 20S BY DAYBREAK FRIDAY...WITH LIKELY ONLY A LIMITED WARM UP INTO THE 30S DURING THE DAY. WITH THIS COLD AIR...MODELS CONTINUE TO SHOW ENOUGH MOISTURE BELOW 800MB FOR CLOUDS AND THERE MAY BE ENOUGH OVER THE LAKE INSTABILITY (850MB TEMPS FALLING TO -11C) TO SUPPORT LAKE CLOUDS OR EVEN SOME TERRAIN ENHANCED SNOW SHOWERS WITH THE NORTHWEST AND EVENTUALLY NORTHERLY WINDS ON FRIDAY. WITH THE DELTA-T VALUES ON THE MARGINAL SIDE...WON/T GO MUCH MORE THAN SLIGHT OR LOW END CHANCE POPS FOR THE FAVORED NORTHWEST WIND UPSLOPE AREAS AFTER MIDNIGHT THURSDAY NIGHT AND THEN GRADUALLY DECREASE THROUGH THE DAY ON FRIDAY WITH THE DRIER AIR QUICKLY ARRIVING AHEAD OF A HIGH IN CENTRAL CANADA. THAT DRY AIR WILL BE SHORT LIVED...AS A WEAK SHORTWAVE AND WEAK SURFACE LOW DIVES SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION LATE FRIDAY NIGHT INTO SATURDAY AND BRINGS A FEW LIGHT SNOW SHOWERS TO THE AREA. WITH LIMITED MOISTURE TO WORK WITH...WILL KEEP ISOLATED SNOW SHOWERS IN THE FORECAST AS IT MOVES THROUGH. AFTER THAT WAVE...INDICATIONS ARE THE REST OF THE WEEKEND WILL BE DRY AS THE HIGH FROM CENTRAL CANADA MOVES THROUGH THE AREA AND THE WISCONSIN BORDER IS BRUSHED BY ANOTHER WAVE ON SUNDAY. WITH THE REGION STILL INFLUENCED BY THE UPPER TROUGH IN EASTERN CANADA...TEMPERATURES WILL REMAIN BELOW NORMAL. SHOULD SEE A GRADUAL MODERATION TO THE TEMPS FOR THE FIRST PART OF NEXT WEEK (BUT STILL REMAINING BELOW NORMAL) AS THE FLOW ALOFT BECOMES WESTERLY AS A UPPER TROUGH AMPLIFIES OVER THE WESTERN CONUS. THIS TROUGH HAS THE POTENTIAL TO PRODUCE A MORE ACTIVE PERIOD OF WEATHER DURING THE MIDDLE OF NEXT WEEK AS DISTURBANCES EJECT EAST-NORTHEAST TOWARDS THE AREA. WILL TREND POPS DOWN ON MONDAY...AS THE LATEST MODELS RUNS ARE PLACING THE WARM FRONT FARTHER SOUTH THAN 24HRS AGO. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 143 PM EDT TUE MAR 31 2015 AN UPPER DISTURBANCE EXITING E OF THE REGION WILL BRING TO AN END SCT -SHSN LATE THIS AFTERNOON AT KCMX AND KSAW. AT KIWD...EXPECT IMPROVEMENT FM MVFR TO VFR ESPECIALLY TOWARD EVENING AS WINDS BECOME LIGHT NE BEHIND THE DISTURBANCE. AT KCMX AND KSAW...EVEN AFTER THE DISTURBANCE MOVES AWAY...SOME LOW CLOUDS/MVFR CIGS MAY LINGER AT LEAST INTO THE EARLY OVERNIGHT TONIGHT UNDER A LOW-LVL E-NE UPSLOPE FLOW AHEAD OF APPROACHING SFC HIGH PRES. EXPECT IMPROVEMENT TO VFR AT KSAW AND KCMX BY LATE WED MORNING WITH INCREASED MIXING AND WINDS BECOMING SE AHEAD OF THE NEXT LOW PRES SYSTEM DEVELOPING OVER THE PLAINS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 413 PM EDT TUE MAR 31 2015 WINDS WILL REMAIN BELOW 25 KNOTS THROUGH MOST OF THE REST OF THE WEEK WITH THE EXCEPTION OF WED AFTERNOON INTO WED EVENING. SOUTH TO SOUTHEAST AE EXPECTED TO INCREASE TO GALES TO 35-40 KTS OVER CENTRAL LAKE SUPERIOR LATE WED AFTERNOON INTO EVENING AHEAD OF A TROUGH MOVING INTO THE WRN GREAT LAKES. THERE COULD BE A FEW GALE FORCE GUSTS ACROSS THE FAR EASTERN END OF LAKE SUPERIOR. WINDS WILL ALSO INCREASE TO NEAR 30 KNOTS THU NIGHT INTO FRIDAY IN THE WAKE OF A COLD FRONT MOVING THROUGH THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 5 PM TO 10 PM EDT WEDNESDAY FOR LSZ244-245. GALE WARNING FROM 5 PM TO 11 PM EDT WEDNESDAY FOR LSZ265. GALE WARNING FROM 5 PM WEDNESDAY TO MIDNIGHT EDT WEDNESDAY NIGHT FOR LSZ264-266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
335 PM EDT TUE MAR 31 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 506 AM EDT TUE MAR 31 2015 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BTWN A TROUGH OVER ERN CANADA AND A RIDGE FROM THE SW CONUS INTO THE CANADIAN ROCKIES. AN UPSTREAM SHORTWAVE TROUGH OVER NW ONTARIO (NW OF LAKE SUPERIOR) SUPPORTED MAINLY LIGHT PCPN. AT THE SFC...LOW PRES ASSOCIATED WITH THE SHRTWV WAS LOCATED NORTH OF KINL. MAINLY CLEAR SKIES OVER UPPER WAS GIVING WAY TO INCREASING MID/HIGH CLOUDS FROM THE WEST AHEAD OF THE LOW PRES SYSTEM. TODAY...THE SHORT RANGE MODELS SUGGEST THAT THE SHRTWV WILL MOVE THROUGH THE NRN LAKES TODAY BRINGING AREAS OF PCPN TO THE CWA. THE SFC LOW TRACK IS ALSO EXPECTED THROUGH CNTRL UPPER MI. AFTER TEMPS REBOUND QUICKLY AFTER SUNRISE...EXPECT ENOUGH WARMING AHEAD OF THE LOW FOR MAINLY RAIN OVER THE WEST...PER NAM FCST WET-BULB ZERO HEIGHTS. THE GREATEST CHANCES/COVERAGE IS EXPECTED OVER THE NORTH AND EAST PORTIONS OF THE CWA IN LINE WITH THE STRONGEST DPVA/QVECTOR CONV. SNOWFALL ARRIVING AS TEMPS CLIMB INTO THE LOWER TO MID 30S SHOULD ONLY AMOUNT TO AROUND A HALF INCH OR LESS. TONIGHT...ANY LINGERING SNOW OVER THE EAST HALF SHOULD DIMINISH DURING THE EVENING AS THE SHRTWV DEPARTS TO THE SE. THERE IS SOME UNCERTAINTY WITH THE AMOUNT/DEPTH OF LOW LEVEL MOISTURE LINGERING BEHIND THE SYSTEM AS A WEAK RIDGE BUILDS INTO THE AREA. WITH AT LEAST PARTIAL CLEARING TEMPS SHOULD DROP INTO THE LOWER TO MID 20S. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 334 PM EDT TUE MAR 31 2015 THE UPPER TROUGH THAT IS CURRENTLY MOVING ONSHORE OVER THE PACIFIC NORTHWEST WILL MOVING THROUGH NORTH DAKOTA AND SOUTHERN SASKATCHEWAN AT THE START OF THE PERIOD. AHEAD OF THIS WAVE...BROAD MID LEVEL WARM AIR ADVECTION WILL BE PRODUCING LIGHT PRECIPITATION (THROUGH SIGNIFICANT DRY AIR BELOW 700MB) AT THE START OF THE PERIOD...BUT IT WILL BE SHIFTING TO THE EAST DURING THE EVENING. MEANWHILE...THE MAIN SURFACE LOW WILL BE BACK IN SOUTHERN SASKATCHEWAN WHILE A TROUGH STRETCHES EAST-SOUTHEAST THROUGH NORTHERN MINNESOTA AND THEN SOUTH INTO IOWA. THIS TROUGH WILL BE THE FOCUS OF THE RAIN CHANCES WEDNESDAY NIGHT INTO THURSDAY MORNING AS IT MOVES ACROSS UPPER MICHIGAN. EXPECT SHOWERS AND THUNDERSTORMS TO FIRE ALONG THIS FRONT WEDNESDAY AFTERNOON FROM CENTRAL MINNESOTA THROUGH IOWA AND THEN QUICKLY MOVE NORTHEAST TOWARDS THE AREA AS THE TROUGH SHIFTS EAST AND WEAKENS. THAT WEAKENING OF THE TROUGH AS IT MOVES THROUGH THE CWA IS A LITTLE CONCERNING...SINCE IT WILL LEAD TO MORE SCATTERED SHOWERS THAN A WIDESPREAD RAIN...ESPECIALLY WITH THE UPSTREAM SHOWERS/THUNDERSTORMS FEEDING OFF THE BETTER MOISTURE/INSTABILITY TRYING TO MOVE INTO THE AREA. WILL CONTINUE TO SHOW CHANCE POPS SHIFTING EAST ACROSS THE CWA WEDNESDAY NIGHT...WITH LIKELY VALUES OVER THE EAST WITH THE DEPARTING WARM AIR ADVECTION AND ALONG THE WISCONSIN BORDER WITH THE BETTER OPPORTUNITY TO SEE THE SHOWERS/THUNDERSTORMS REACHING THAT AREA. WILL CONTINUE TO INCLUDE THUNDER ALONG THE WISCONSIN BORDER...AS THAT AREA WOULD HAVE THE BEST OPPORTUNITY OF THUNDERSTORMS MOVING NORTHEAST INTO THE CWA FROM THE CONVECTION TIED TO THE DIMINISHING INSTABILITY THROUGH THE NIGHT. AS THIS TROUGH SHIFTS THROUGH THE EASTERN U.P. ON THURSDAY MORNING...WILL SHOW LINGERING SHOWERS IN THAT AREA BEFORE QUICKLY ENDING AS THE DRY SLOT MOVES OVER UPPER MICHIGAN. THIS DRY SLOT WILL LEAD TO A DECREASING CLOUDS AND A WARM DAY ACROSS THE U.P. UNDER GUSTY WESTERLY WINDS. WITH TEMPERATURES WARMING THROUGH THE NIGHT ON WEDNESDAY NIGHT...WILL HAVE A WARM START TO THE DAY AND THE INCREASING SUNSHINE WILL ALLOW HIGHS TO RISE INTO THE 50S FOR MOST LOCATIONS AND EVEN SOME LOW 60S FOR THE DOWNSLOPE AREAS OF THE SOUTH CENTRAL CWA. FOR LOCATIONS WITHOUT SNOW...ESPECIALLY OVER THE SOUTH CENTRAL...THE PATTERN IS FAVORABLE FOR FIRES (LOW TO THE NORTH...GUSTY WESTERLY WINDS...AND DRY LOW LEVEL AIR). HOPEFULLY...ANY OPEN DEBRIS BURNING WILL BE LIMITED AND CAREFULLY TENDED OVER THE SOUTH CENTRAL AS CONDITIONS ARE SUPPORTIVE FOR FIRE SPREADING (ESPECIALLY IF RAINFALL THE NIGHT BEFORE IS LIMITED). THE WARM AIR WILL BE SHORT LIVED AS MUCH COLDER AIR SURGES INTO THE AREA THURSDAY NIGHT BEHIND THE TRAILING COLD FRONT. THIS WILL STEADILY DROP TEMPS THROUGH THE NIGHT AND INTO THE 20S BY DAYBREAK FRIDAY...WITH LIKELY ONLY A LIMITED WARM UP INTO THE 30S DURING THE DAY. WITH THIS COLD AIR...MODELS CONTINUE TO SHOW ENOUGH MOISTURE BELOW 800MB FOR CLOUDS AND THERE MAY BE ENOUGH OVER THE LAKE INSTABILITY (850MB TEMPS FALLING TO -11C) TO SUPPORT LAKE CLOUDS OR EVEN SOME TERRAIN ENHANCED SNOW SHOWERS WITH THE NORTHWEST AND EVENTUALLY NORTHERLY WINDS ON FRIDAY. WITH THE DELTA-T VALUES ON THE MARGINAL SIDE...WON/T GO MUCH MORE THAN SLIGHT OR LOW END CHANCE POPS FOR THE FAVORED NORTHWEST WIND UPSLOPE AREAS AFTER MIDNIGHT THURSDAY NIGHT AND THEN GRADUALLY DECREASE THROUGH THE DAY ON FRIDAY WITH THE DRIER AIR QUICKLY ARRIVING AHEAD OF A HIGH IN CENTRAL CANADA. THAT DRY AIR WILL BE SHORT LIVED...AS A WEAK SHORTWAVE AND WEAK SURFACE LOW DIVES SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION LATE FRIDAY NIGHT INTO SATURDAY AND BRINGS A FEW LIGHT SNOW SHOWERS TO THE AREA. WITH LIMITED MOISTURE TO WORK WITH...WILL KEEP ISOLATED SNOW SHOWERS IN THE FORECAST AS IT MOVES THROUGH. AFTER THAT WAVE...INDICATIONS ARE THE REST OF THE WEEKEND WILL BE DRY AS THE HIGH FROM CENTRAL CANADA MOVES THROUGH THE AREA AND THE WISCONSIN BORDER IS BRUSHED BY ANOTHER WAVE ON SUNDAY. WITH THE REGION STILL INFLUENCED BY THE UPPER TROUGH IN EASTERN CANADA...TEMPERATURES WILL REMAIN BELOW NORMAL. SHOULD SEE A GRADUAL MODERATION TO THE TEMPS FOR THE FIRST PART OF NEXT WEEK (BUT STILL REMAINING BELOW NORMAL) AS THE FLOW ALOFT BECOMES WESTERLY AS A UPPER TROUGH AMPLIFIES OVER THE WESTERN CONUS. THIS TROUGH HAS THE POTENTIAL TO PRODUCE A MORE ACTIVE PERIOD OF WEATHER DURING THE MIDDLE OF NEXT WEEK AS DISTURBANCES EJECT EAST-NORTHEAST TOWARDS THE AREA. WILL TREND POPS DOWN ON MONDAY...AS THE LATEST MODELS RUNS ARE PLACING THE WARM FRONT FARTHER SOUTH THAN 24HRS AGO. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 143 PM EDT TUE MAR 31 2015 AN UPPER DISTURBANCE EXITING E OF THE REGION WILL BRING TO AN END SCT -SHSN LATE THIS AFTERNOON AT KCMX AND KSAW. AT KIWD...EXPECT IMPROVEMENT FM MVFR TO VFR ESPECIALLY TOWARD EVENING AS WINDS BECOME LIGHT NE BEHIND THE DISTURBANCE. AT KCMX AND KSAW...EVEN AFTER THE DISTURBANCE MOVES AWAY...SOME LOW CLOUDS/MVFR CIGS MAY LINGER AT LEAST INTO THE EARLY OVERNIGHT TONIGHT UNDER A LOW-LVL E-NE UPSLOPE FLOW AHEAD OF APPROACHING SFC HIGH PRES. EXPECT IMPROVEMENT TO VFR AT KSAW AND KCMX BY LATE WED MORNING WITH INCREASED MIXING AND WINDS BECOMING SE AHEAD OF THE NEXT LOW PRES SYSTEM DEVELOPING OVER THE PLAINS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 517 AM EDT TUE MAR 31 2015 WINDS WILL REMAIN BELOW 25 KNOTS THROUGH MOST OF THE REST OF THE WEEK. HOWEVER...SOUTH TO SOUTHEAST WINDS UP TO 30 KNOTS ARE POSSIBLE LATE WED INTO WED NIGHT AHEAD OF A TROUGH MOVING INTO THE WRN GREAT LAKES. THERE COULD BE A FEW GALE FORCE GUSTS ACROSS THE EAST HALF OF LAKE SUPERIOR. WINDS WILL ALSO INCREASE TO NEAR 30 KNOTS THU NIGHT INTO FRIDAY IN THE WAKE OF A COLD FRONT MOVING THROUGH THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 5 PM TO 10 PM EDT WEDNESDAY FOR LSZ244-245. GALE WARNING FROM 5 PM TO 11 PM EDT WEDNESDAY FOR LSZ265. GALE WARNING FROM 5 PM WEDNESDAY TO MIDNIGHT EDT WEDNESDAY NIGHT FOR LSZ264-266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...VOSS MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
157 PM EDT TUE MAR 31 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 506 AM EDT TUE MAR 31 2015 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BTWN A TROUGH OVER ERN CANADA AND A RIDGE FROM THE SW CONUS INTO THE CANADIAN ROCKIES. AN UPSTREAM SHORTWAVE TROUGH OVER NW ONTARIO (NW OF LAKE SUPERIOR) SUPPORTED MAINLY LIGHT PCPN. AT THE SFC...LOW PRES ASSOCIATED WITH THE SHRTWV WAS LOCATED NORTH OF KINL. MAINLY CLEAR SKIES OVER UPPER WAS GIVING WAY TO INCREASING MID/HIGH CLOUDS FROM THE WEST AHEAD OF THE LOW PRES SYSTEM. TODAY...THE SHORT RANGE MODELS SUGGEST THAT THE SHRTWV WILL MOVE THROUGH THE NRN LAKES TODAY BRINGING AREAS OF PCPN TO THE CWA. THE SFC LOW TRACK IS ALSO EXPECTED THROUGH CNTRL UPPER MI. AFTER TEMPS REBOUND QUICKLY AFTER SUNRISE...EXPECT ENOUGH WARMING AHEAD OF THE LOW FOR MAINLY RAIN OVER THE WEST...PER NAM FCST WET-BULB ZERO HEIGHTS. THE GREATEST CHANCES/COVERAGE IS EXPECTED OVER THE NORTH AND EAST PORTIONS OF THE CWA IN LINE WITH THE STRONGEST DPVA/QVECTOR CONV. SNOWFALL ARRIVING AS TEMPS CLIMB INTO THE LOWER TO MID 30S SHOULD ONLY AMOUNT TO AROUND A HALF INCH OR LESS. TONIGHT...ANY LINGERING SNOW OVER THE EAST HALF SHOULD DIMINISH DURING THE EVENING AS THE SHRTWV DEPARTS TO THE SE. THERE IS SOME UNCERTAINTY WITH THE AMOUNT/DEPTH OF LOW LEVEL MOISTURE LINGERING BEHIND THE SYSTEM AS A WEAK RIDGE BUILDS INTO THE AREA. WITH AT LEAST PARTIAL CLEARING TEMPS SHOULD DROP INTO THE LOWER TO MID 20S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 340 AM EDT TUE MAR 31 2015 A LOW PRESSURE SYSTEM WILL MOVE ACROSS SRN SASKATCHEWAN ON WED...WITH A SFC-850MB TROUGH MOVING TO JUST W OF THE CWA BY 00Z THU...WELL E OF THE OCCLUDED SYSTEM. MODELS SHOW VARYING MAGNITUDES OF PRECIP ASSOCIATED WITH THE MID LEVEL WAA AHEAD OF THE TROUGH...BUT PREFER THE DRIER OPTIONS GIVEN THE DEGREE OF DRY LOW- MID LEVEL AIR. THE TROUGH WEAKENS AS IT MOVES THROUGH THE AREA BETWEEN 00Z AND 18Z THU. RAIN WILL BE LARGELY TIED TO THE TROUGH...BUT WITH IT WEAKENING AS IT MOVES ACROSS THE AREA AND CONVECTION TO THE S AND SW OF THE AREA...AM NOT OVERLY CONFIDENT ON PRECIP AMOUNTS OVER THE W. AS THE TROUGH CATCHES UP WITH THE BETTER WAA OVER ERN UPPER MI WED EVENING/NIGHT WILL SHOW INCREASES POPS/QPF GIVEN BETTER FORCING/MOISTURE. WILL CONTINUE TO SHOW THUNDER CHANCES ALONG THE WI BORDER ON WED EVENING...WITH DIMINISHING CHANCES WED NIGHT AS DAYTIME HEATING FADES. WINDS WILL BE GUSTY OUT AHEAD OF THE TROUGH...ESPECIALLY IN DOWNSLOPING AREAS WITH SLY WINDS OVER WRN UPPER MI. ERN AND MAYBE EVEN CENTRAL UPPER MI WILL BE DOWNWIND OF LAKE MICHIGAN AND...THEREFORE...WILL BE MORE STABLE AND COOLER DURING THE DAY. HAVE HIGH TEMPS IN THE MID TO UPPER 50S OVER THE WRN U.P. AND FROM THE UPPER 30S TO 40S OVER THE CENTRAL AND E DOWNWIND OF LAKE MICHIGAN. THE DRY SLOT WILL MOVE IN ON THU...LEADING TO A DRY FORECAST BEHIND THE TROUGH. MODELS SUGGEST MIXING AS HIGH AS 700MB...WHICH WOULD TAP INTO SOME DRY AIR AND BRING SFC DEW POINTS DOWN. ALSO...IT WILL BE BREEZY OUT OF THE W...WHICH WILL HELP EVEN ERN UPPER MI SEE WARMER TEMPS. HIGHS WILL TOP OUT MAINLY IN THE 50S TO LOW 60S...WARMEST SCENTRAL. FORTUNATELY...STILL HAVE DECENT SNOW COVER OVER MUCH OF THE U.P. AS THIS PATTERN IS ONE OF THE CLASSIC FIRE WEATHER DAYS FROM PAST U.P. FIRES. THE MAIN UPPER TROUGH/SHORTWAVE FROM THE WED SYSTEM MOVES OVER THU EVENING/NIGHT...BRINGING COLDER AIR /850MB TEMPS TO -12C/ AND ENOUGH FORCING FOR ISOLATED TO SCATTERED UPSLOPE SNOW SHOWERS IN AREAS FAVORED BY NW WINDS. ALTHOUGH AMOUNTS ARE PRETTY UNCERTAIN...COULD SEE A COUPLE INCHES OF SNOW THU EVENING/NIGHT. FRI THROUGH MON LOOK BELOW NORMAL TEMPERATURE WISE AS NW FLOW BECOMES MORE ZONAL EARLY NEXT WEEK. A SHORTWAVE MAY PASS OVERHEAD ON SAT...LEADING TO SOME LIGHT SNOW POTENTIAL. OTHERWISE...NO SIGNIFICANT WEATHER FRI THROUGH SUN. MODEL DO SHOW A SYSTEM MOVING INTO THE REGION ON MON/TUE...POSSIBLY PRODUCING PRECIP. GIVEN HIGH LEVELS OF UNCERTAINTY FRI THROUGH MON...WILL USE A CONSENSUS OF GUIDANCE FOR THIS TIME FRAME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 143 PM EDT TUE MAR 31 2015 AN UPPER DISTURBANCE EXITING E OF THE REGION WILL BRING TO AN END SCT -SHSN LATE THIS AFTERNOON AT KCMX AND KSAW. AT KIWD...EXPECT IMPROVEMENT FM MVFR TO VFR ESPECIALLY TOWARD EVENING AS WINDS BECOME LIGHT NE BEHIND THE DISTURBANCE. AT KCMX AND KSAW...EVEN AFTER THE DISTURBANCE MOVES AWAY...SOME LOW CLOUDS/MVFR CIGS MAY LINGER AT LEAST INTO THE EARLY OVERNIGHT TONIGHT UNDER A LOW-LVL E-NE UPSLOPE FLOW AHEAD OF APPROACHING SFC HIGH PRES. EXPECT IMPROVEMENT TO VFR AT KSAW AND KCMX BY LATE WED MORNING WITH INCREASED MIXING AND WINDS BECOMING SE AHEAD OF THE NEXT LOW PRES SYSTEM DEVELOPING OVER THE PLAINS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 517 AM EDT TUE MAR 31 2015 WINDS WILL REMAIN BELOW 25 KNOTS THROUGH MOST OF THE REST OF THE WEEK. HOWEVER...SOUTH TO SOUTHEAST WINDS UP TO 30 KNOTS ARE POSSIBLE LATE WED INTO WED NIGHT AHEAD OF A TROUGH MOVING INTO THE WRN GREAT LAKES. THERE COULD BE A FEW GALE FORCE GUSTS ACROSS THE EAST HALF OF LAKE SUPERIOR. WINDS WILL ALSO INCREASE TO NEAR 30 KNOTS THU NIGHT INTO FRIDAY IN THE WAKE OF A COLD FRONT MOVING THROUGH THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...VOSS MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
517 AM EDT TUE MAR 31 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 506 AM EDT TUE MAR 31 2015 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BTWN A TROUGH OVER ERN CANADA AND A RIDGE FROM THE SW CONUS INTO THE CANADIAN ROCKIES. AN UPSTREAM SHORTWAVE TROUGH OVER NW ONTARIO (NW OF LAKE SUPERIOR) SUPPORTED MAINLY LIGHT PCPN. AT THE SFC...LOW PRES ASSOCIATED WITH THE SHRTWV WAS LOCATED NORTH OF KINL. MAINLY CLEAR SKIES OVER UPPER WAS GIVING WAY TO INCREASING MID/HIGH CLOUDS FROM THE WEST AHEAD OF THE LOW PRES SYSTEM. TODAY...THE SHORT RANGE MODELS SUGGEST THAT THE SHRTWV WILL MOVE THROUGH THE NRN LAKES TODAY BRINGING AREAS OF PCPN TO THE CWA. THE SFC LOW TRACK IS ALSO EXPECTED THROUGH CNTRL UPPER MI. AFTER TEMPS REBOUND QUICKLY AFTER SUNRISE...EXPECT ENOUGH WARMING AHEAD OF THE LOW FOR MAINLY RAIN OVER THE WEST...PER NAM FCST WET-BULB ZERO HEIGHTS. THE GREATEST CHANCES/COVERAGE IS EXPECTED OVER THE NORTH AND EAST PORTIONS OF THE CWA IN LINE WITH THE STRONGEST DPVA/QVECTOR CONV. SNOWFALL ARRIVING AS TEMPS CLIMB INTO THE LOWER TO MID 30S SHOULD ONLY AMOUNT TO AROUND A HALF INCH OR LESS. TONIGHT...ANY LINGERING SNOW OVER THE EAST HALF SHOULD DIMINISH DURING THE EVENING AS THE SHRTWV DEPARTS TO THE SE. THERE IS SOME UNCERTAINTY WITH THE AMOUNT/DEPTH OF LOW LEVEL MOISTURE LINGERING BEHIND THE SYSTEM AS A WEAK RIDGE BUILDS INTO THE AREA. WITH AT LEAST PARTIAL CLEARING TEMPS SHOULD DROP INTO THE LOWER TO MID 20S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 340 AM EDT TUE MAR 31 2015 A LOW PRESSURE SYSTEM WILL MOVE ACROSS SRN SASKATCHEWAN ON WED...WITH A SFC-850MB TROUGH MOVING TO JUST W OF THE CWA BY 00Z THU...WELL E OF THE OCCLUDED SYSTEM. MODELS SHOW VARYING MAGNITUDES OF PRECIP ASSOCIATED WITH THE MID LEVEL WAA AHEAD OF THE TROUGH...BUT PREFER THE DRIER OPTIONS GIVEN THE DEGREE OF DRY LOW- MID LEVEL AIR. THE TROUGH WEAKENS AS IT MOVES THROUGH THE AREA BETWEEN 00Z AND 18Z THU. RAIN WILL BE LARGELY TIED TO THE TROUGH...BUT WITH IT WEAKENING AS IT MOVES ACROSS THE AREA AND CONVECTION TO THE S AND SW OF THE AREA...AM NOT OVERLY CONFIDENT ON PRECIP AMOUNTS OVER THE W. AS THE TROUGH CATCHES UP WITH THE BETTER WAA OVER ERN UPPER MI WED EVENING/NIGHT WILL SHOW INCREASES POPS/QPF GIVEN BETTER FORCING/MOISTURE. WILL CONTINUE TO SHOW THUNDER CHANCES ALONG THE WI BORDER ON WED EVENING...WITH DIMINISHING CHANCES WED NIGHT AS DAYTIME HEATING FADES. WINDS WILL BE GUSTY OUT AHEAD OF THE TROUGH...ESPECIALLY IN DOWNSLOPING AREAS WITH SLY WINDS OVER WRN UPPER MI. ERN AND MAYBE EVEN CENTRAL UPPER MI WILL BE DOWNWIND OF LAKE MICHIGAN AND...THEREFORE...WILL BE MORE STABLE AND COOLER DURING THE DAY. HAVE HIGH TEMPS IN THE MID TO UPPER 50S OVER THE WRN U.P. AND FROM THE UPPER 30S TO 40S OVER THE CENTRAL AND E DOWNWIND OF LAKE MICHIGAN. THE DRY SLOT WILL MOVE IN ON THU...LEADING TO A DRY FORECAST BEHIND THE TROUGH. MODELS SUGGEST MIXING AS HIGH AS 700MB...WHICH WOULD TAP INTO SOME DRY AIR AND BRING SFC DEW POINTS DOWN. ALSO...IT WILL BE BREEZY OUT OF THE W...WHICH WILL HELP EVEN ERN UPPER MI SEE WARMER TEMPS. HIGHS WILL TOP OUT MAINLY IN THE 50S TO LOW 60S...WARMEST SCENTRAL. FORTUNATELY...STILL HAVE DECENT SNOW COVER OVER MUCH OF THE U.P. AS THIS PATTERN IS ONE OF THE CLASSIC FIRE WEATHER DAYS FROM PAST U.P. FIRES. THE MAIN UPPER TROUGH/SHORTWAVE FROM THE WED SYSTEM MOVES OVER THU EVENING/NIGHT...BRINGING COLDER AIR /850MB TEMPS TO -12C/ AND ENOUGH FORCING FOR ISOLATED TO SCATTERED UPSLOPE SNOW SHOWERS IN AREAS FAVORED BY NW WINDS. ALTHOUGH AMOUNTS ARE PRETTY UNCERTAIN...COULD SEE A COUPLE INCHES OF SNOW THU EVENING/NIGHT. FRI THROUGH MON LOOK BELOW NORMAL TEMPERATURE WISE AS NW FLOW BECOMES MORE ZONAL EARLY NEXT WEEK. A SHORTWAVE MAY PASS OVERHEAD ON SAT...LEADING TO SOME LIGHT SNOW POTENTIAL. OTHERWISE...NO SIGNIFICANT WEATHER FRI THROUGH SUN. MODEL DO SHOW A SYSTEM MOVING INTO THE REGION ON MON/TUE...POSSIBLY PRODUCING PRECIP. GIVEN HIGH LEVELS OF UNCERTAINTY FRI THROUGH MON...WILL USE A CONSENSUS OF GUIDANCE FOR THIS TIME FRAME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 124 AM EDT TUE MAR 31 2015 THERE MAY BE A BRIEF PERIOD OF UPSLOPE STRATUS IFR CIGS AT CMX OVERNIGHT. OTHERWISE...WITH VERY DRY LLVL AIR SHOWN ON THE 00Z INL RAOB ASSOCAITED WITH HI PRES NEAR ERN LK SUP...EXPECT VFR CONDITIONS TO PREDOMINATE. A DISTURBANCE APRCHG FM THE NW TODAY WL MOVE OVER UPR MI...BRINGING A BETTER CHC FOR SOME -SN POSSIBLY MIXED WITH RA TO MAINLY CMX AND SAW...ALONG WITH A PERIOD OF MVFR AND PERHAPS IFR CONDITIONS FOR THOSE SITES. SINCE LESS PCPN IS LIKELY TO FALL AT IWD...FCST ONLY A MARGINAL MVFR CONDITION AT THAT SITE. EVEN AFTER THE DISTURBANCE MOVES AWAY...SOME LO CLDS/MVFR CIGS MAY LINGER AT CMX AND ESPECIALLY SAW...WHERE A LLVL UPSLOPE NNE WIND WL PREVAIL AHEAD OF APRCHG HI PRES. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 517 AM EDT TUE MAR 31 2015 WINDS WILL REMAIN BELOW 25 KNOTS THROUGH MOST OF THE REST OF THE WEEK. HOWEVER...SOUTH TO SOUTHEAST WINDS UP TO 30 KNOTS ARE POSSIBLE LATE WED INTO WED NIGHT AHEAD OF A TROUGH MOVING INTO THE WRN GREAT LAKES. THERE COULD BE A FEW GALE FORCE GUSTS ACROSS THE EAST HALF OF LAKE SUPERIOR. WINDS WILL ALSO INCREASE TO NEAR 30 KNOTS THU NIGHT INTO FRIDAY IN THE WAKE OF A COLD FRONT MOVING THROUGH THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...KC MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
507 AM EDT TUE MAR 31 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 506 AM EDT TUE MAR 31 2015 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BTWN A TROUGH OVER ERN CANADA AND A RIDGE FROM THE SW CONUS INTO THE CANADIAN ROCKIES. AN UPSTREAM SHORTWAVE TROUGH OVER NW ONTARIO (NW OF LAKE SUPERIOR) SUPPORTED MAINLY LIGHT PCPN. AT THE SFC...LOW PRES ASSOCIATED WITH THE SHRTWV WAS LOCATED NORTH OF KINL. MAINLY CLEAR SKIES OVER UPPER WAS GIVING WAY TO INCREASING MID/HIGH CLOUDS FROM THE WEST AHEAD OF THE LOW PRES SYSTEM. TODAY...THE SHORT RANGE MODELS SUGGEST THAT THE SHRTWV WILL MOVE THROUGH THE NRN LAKES TODAY BRINGING AREAS OF PCPN TO THE CWA. THE SFC LOW TRACK IS ALSO EXPECTED THROUGH CNTRL UPPER MI. AFTER TEMPS REBOUND QUICKLY AFTER SUNRISE...EXPECT ENOUGH WARMING AHEAD OF THE LOW FOR MAINLY RAIN OVER THE WEST...PER NAM FCST WET-BULB ZERO HEIGHTS. THE GREATEST CHANCES/COVERAGE IS EXPECTED OVER THE NORTH AND EAST PORTIONS OF THE CWA IN LINE WITH THE STRONGEST DPVA/QVECTOR CONV. SNOWFALL ARRIVING AS TEMPS CLIMB INTO THE LOWER TO MID 30S SHOULD ONLY AMOUNT TO AROUND A HALF INCH OR LESS. TONIGHT...ANY LINGERING SNOW OVER THE EAST HALF SHOULD DIMINISH DURING THE EVENING AS THE SHRTWV DEPARTS TO THE SE. THERE IS SOME UNCERTAINTY WITH THE AMOUNT/DEPTH OF LOW LEVEL MOISTURE LINGERING BEHIND THE SYSTEM AS A WEAK RIDGE BUILDS INTO THE AREA. WITH AT LEAST PARTIAL CLEARING TEMPS SHOULD DROP INTO THE LOWER TO MID 20S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 340 AM EDT TUE MAR 31 2015 A LOW PRESSURE SYSTEM WILL MOVE ACROSS SRN SASKATCHEWAN ON WED...WITH A SFC-850MB TROUGH MOVING TO JUST W OF THE CWA BY 00Z THU...WELL E OF THE OCCLUDED SYSTEM. MODELS SHOW VARYING MAGNITUDES OF PRECIP ASSOCIATED WITH THE MID LEVEL WAA AHEAD OF THE TROUGH...BUT PREFER THE DRIER OPTIONS GIVEN THE DEGREE OF DRY LOW- MID LEVEL AIR. THE TROUGH WEAKENS AS IT MOVES THROUGH THE AREA BETWEEN 00Z AND 18Z THU. RAIN WILL BE LARGELY TIED TO THE TROUGH...BUT WITH IT WEAKENING AS IT MOVES ACROSS THE AREA AND CONVECTION TO THE S AND SW OF THE AREA...AM NOT OVERLY CONFIDENT ON PRECIP AMOUNTS OVER THE W. AS THE TROUGH CATCHES UP WITH THE BETTER WAA OVER ERN UPPER MI WED EVENING/NIGHT WILL SHOW INCREASES POPS/QPF GIVEN BETTER FORCING/MOISTURE. WILL CONTINUE TO SHOW THUNDER CHANCES ALONG THE WI BORDER ON WED EVENING...WITH DIMINISHING CHANCES WED NIGHT AS DAYTIME HEATING FADES. WINDS WILL BE GUSTY OUT AHEAD OF THE TROUGH...ESPECIALLY IN DOWNSLOPING AREAS WITH SLY WINDS OVER WRN UPPER MI. ERN AND MAYBE EVEN CENTRAL UPPER MI WILL BE DOWNWIND OF LAKE MICHIGAN AND...THEREFORE...WILL BE MORE STABLE AND COOLER DURING THE DAY. HAVE HIGH TEMPS IN THE MID TO UPPER 50S OVER THE WRN U.P. AND FROM THE UPPER 30S TO 40S OVER THE CENTRAL AND E DOWNWIND OF LAKE MICHIGAN. THE DRY SLOT WILL MOVE IN ON THU...LEADING TO A DRY FORECAST BEHIND THE TROUGH. MODELS SUGGEST MIXING AS HIGH AS 700MB...WHICH WOULD TAP INTO SOME DRY AIR AND BRING SFC DEW POINTS DOWN. ALSO...IT WILL BE BREEZY OUT OF THE W...WHICH WILL HELP EVEN ERN UPPER MI SEE WARMER TEMPS. HIGHS WILL TOP OUT MAINLY IN THE 50S TO LOW 60S...WARMEST SCENTRAL. FORTUNATELY...STILL HAVE DECENT SNOW COVER OVER MUCH OF THE U.P. AS THIS PATTERN IS ONE OF THE CLASSIC FIRE WEATHER DAYS FROM PAST U.P. FIRES. THE MAIN UPPER TROUGH/SHORTWAVE FROM THE WED SYSTEM MOVES OVER THU EVENING/NIGHT...BRINGING COLDER AIR /850MB TEMPS TO -12C/ AND ENOUGH FORCING FOR ISOLATED TO SCATTERED UPSLOPE SNOW SHOWERS IN AREAS FAVORED BY NW WINDS. ALTHOUGH AMOUNTS ARE PRETTY UNCERTAIN...COULD SEE A COUPLE INCHES OF SNOW THU EVENING/NIGHT. FRI THROUGH MON LOOK BELOW NORMAL TEMPERATURE WISE AS NW FLOW BECOMES MORE ZONAL EARLY NEXT WEEK. A SHORTWAVE MAY PASS OVERHEAD ON SAT...LEADING TO SOME LIGHT SNOW POTENTIAL. OTHERWISE...NO SIGNIFICANT WEATHER FRI THROUGH SUN. MODEL DO SHOW A SYSTEM MOVING INTO THE REGION ON MON/TUE...POSSIBLY PRODUCING PRECIP. GIVEN HIGH LEVELS OF UNCERTAINTY FRI THROUGH MON...WILL USE A CONSENSUS OF GUIDANCE FOR THIS TIME FRAME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 124 AM EDT TUE MAR 31 2015 THERE MAY BE A BRIEF PERIOD OF UPSLOPE STRATUS IFR CIGS AT CMX OVERNIGHT. OTHERWISE...WITH VERY DRY LLVL AIR SHOWN ON THE 00Z INL RAOB ASSOCAITED WITH HI PRES NEAR ERN LK SUP...EXPECT VFR CONDITIONS TO PREDOMINATE. A DISTURBANCE APRCHG FM THE NW TODAY WL MOVE OVER UPR MI...BRINGING A BETTER CHC FOR SOME -SN POSSIBLY MIXED WITH RA TO MAINLY CMX AND SAW...ALONG WITH A PERIOD OF MVFR AND PERHAPS IFR CONDITIONS FOR THOSE SITES. SINCE LESS PCPN IS LIKELY TO FALL AT IWD...FCST ONLY A MARGINAL MVFR CONDITION AT THAT SITE. EVEN AFTER THE DISTURBANCE MOVES AWAY...SOME LO CLDS/MVFR CIGS MAY LINGER AT CMX AND ESPECIALLY SAW...WHERE A LLVL UPSLOPE NNE WIND WL PREVAIL AHEAD OF APRCHG HI PRES. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 239 PM EDT MON MAR 30 2015 WINDS WILL REMAIN BELOW 25 KNOTS THROUGH MOST OF THE REST OF THE WEEK. HOWEVER...SOUTH TO SOUTHEAST WINDS UP TO 30 KNOTS ARE POSSIBLE LATE WED INTO WED NIGHT. THERE COULD BE A FEW GALE FORCE GUSTS ACROSS THE EAST HALF OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...KC MARINE...07
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
659 PM CDT Wed Apr 1 2015 .UPDATE: Issued at 655 PM CDT Wed Apr 1 2015 Update for mainly PoP adjustments based largely on latest RADAR trends. Trended twd the local 4km WRF and HRRR solns. However, some question still remains how far NE these SHRA will hold together. TS is becoming more isod with loss of insolation and believe this trend will continue thru the evening. The area of SHRA shud also gradually dissipate and become more isod to sct. Will continue to monitor as the system develops. && .SHORT TERM: (Through Late Tonight) Issued at 345 PM CDT Wed Apr 1 2015 MCV moving into southwest Missouri is producing an area of rain with embedded thunderstorms. This activity is moving northeast and should enter the CWFA around 21Z. Have therefore raised PoPs to likely for parts of central Missouri. Not sure how far north/northeast the rain is going to get though as some fairly dry mid-level air as shown by AMDAR soundings from KSTL this afternoon. However, the 850mb flow will be turning to the southwest and the atmosphere will be moistening up...so PoPs may not be high enough over some parts of the area this evening. Attention turns to the cold front over the Plains and what will be forming out there tonight. Guidance suggests that the storms will form over Nebraska this evening and move southeast overnight. Current thinking is that the leading edge of the precipitation will enter the northern portion of the CWFA between 09Z and 12Z. Storms should be on the downward trend at that point, but with MUCAPE still potentially at or above 1000 J/kg, and around 40kts of deep layer shear, strong storms remain a possibility across northeast Missouri and west central Illinois before sunrise Thursday. Carney .LONG TERM: (Thursday through Next Wednesday) Issued at 345 PM CDT Wed Apr 1 2015 Active cold front to move through region on Thursday. Will see initial activity that forms ahead of front slide southeast and diminish by 15z. Then a bit of a break before more intense round develops during the afternoon hours. Will see MU capes approach 1500 J/kg, mainly along and south of I70 and PW values around 1.3". Despite the cloud cover from the morning activity, any breaks in the cloud cover will help to destabilize the atmosphere even more. Some of the storms could be strong to severe with the main threats being large hail and damaging winds. As for high temps, they will range from the upper 60s far north to the low to mid 70s south. Front to stall out over southern portions of forecast area Thursday night and will see several waves of precipitation through Friday, with best chances along and south of I-70. Lows Thursday night will be in the mid 40s to upper 50s. Then colder air to filter in on Friday as system slowly sinks south away from region. Will see non diurnal temps, either steady or slowly falling. Highs will only be in the low 50s far north to the low 60s far south. Then dry weather expected for the weekend as surface ridge builds in, with temperatures slowly moderating. Highs on Saturday will be in the mid 50s to low 60s then warm up into the mid 60s everywhere on Sunday. (Sunday night through Wednesday) Beyond that, active pattern begins with systems sliding northeast towards forecast area through mid week next week. Extended models have differences in timing with these systems, so just kept chance pops through the period. Showers and thunderstorms to move in Sunday night and continue off and on through next Wednesday. Highs will be in the 60s and 70s through this period. Byrd && .AVIATION: (For the 18z TAFs through 18z Thursday Afternoon) Issued at 1242 PM CDT Wed Apr 1 2015 Area of showers with embedded thunderstorms over southwest Missouri will continue moving northeast this afternoon. Not sure what the coverage will be as it gets into our forecast area, but scattered seems likely. Flight conditions should remain VFR except under heavier rain/thunderstorms. Rain should dissipate slowly through mid to late evening as it continues moving northeast. Still expecting LLWS conditions tonight as the low level jet increases ahead of an approaching cold front. Thunderstorms are expected to develop tonight over Nebraska and move southeast ahead of the front and should push into northeast Missouri between 10-12Z. Storms should be weakening as the move into our area, but will likely still be strong enough to produce MVFR and possibly brief IFR conditions. As the storms continue to move east into eastern Missouri and southwest Illinois they will continue to weaken until there will be little if any thunder left by 14-16Z. Another round of strong storms is expected ahead of the front Thursday afternoon. Specifics for KSTL: Area of showers with embedded thunderstorms over southwest Missouri will continue moving northeast this afternoon. Believe the rain will be dissipating as it moves toward the STL Metro area this evening, but several pieces of guidance do show thunderstorms in the vicinity of the terminal for a short time this evening. Flight conditions should remain VFR unless a thunderstorm hits the terminal directly. Still expecting LLWS conditions tonight as the low level jet increases ahead of an approaching cold front. Thunderstorms are expected to develop tonight over Nebraska and move southeast ahead of the the front. By the time the storms reach Lambert around 14Z they should be weakening. Another round of strong storms is expected ahead of the front Thursday afternoon. Carney && .PRELIMINARY POINT TEMPS/POPS: Saint Louis 60 74 53 56 / 60 80 80 70 Quincy 58 68 46 50 / 60 80 30 50 Columbia 60 71 48 53 / 70 80 70 60 Jefferson City 59 72 50 54 / 70 80 80 60 Salem 57 72 54 57 / 20 80 80 80 Farmington 60 72 54 58 / 50 70 80 80 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
636 PM CDT Wed Apr 1 2015 .DISCUSSION... Issued at 427 PM CDT WED APR 1 2015 Tonight - Thursday: In the very near term an area of convection tied to a pesky MCV over southwestern MO is expected to track northeast and graze the far southeast CWA through early evening. Have increased PoPs over this region to account for this. Attention then turns back to the west and northwest and focuses on two areas...the NE/SD cold front and an area of accas from western KS into the TX Panhandle. Per latest RAP analysis and visible satellite imagery the airmass remains capped within the cold fronts baroclinic zone. Low-level moisture taking its time to arrive. Latest NAM/RAP suggest CIN may not be eroded till closer to 00Z. Still expect a line of convection to form this evening with the front sliding east-southeast overnight. This activity expected to reach far northwest MO towards midnight and then continue across northern MO. Second area being watched is the KS accas and 12z NAM defined a h7 shortwave/vorticity max that will move out of CO this evening. Last several runs of the convective allowing HRRR generates an expanding area of elevated convection which tracks east overnight, crossing the KS/MO border after midnight. 18z NAM qpf hints at this convection but delays the arrival till after 09z. Will side towards the HRRR for now. While the severe threat will be greatly muted due to its arrival time and minimal instability some generous qpf is possible over our northern and western counties. The latter due to the southerly low level jet veering overnight and paralleling the cold front which could result in some post frontal training for several hours. Convection likely to exit the CWA quickly from west to east Thursday morning. However, model consensus indicates the front will stall just south of the CWA, close enough that low chance afternoon PoPs necessary across the far southern counties to account for potential late afternoon redevelopment. Thursday night - Friday night: The aforementioned stalled front will likely remain just south of the CWA during this period. However, post frontal stratiform or weak elevated convective rains are likely north of the boundary Thursday night into Friday morning. An upper level trough is progged to shift eastward within a pseudo westerly flow with pieces of energy ejecting ahead of it through the Central Plains. This should allow for some isentropically induced rain to form and affect most of the CWA. The rain chances will end by Friday afternoon with the passage of the trough axis. Temperatures will be on the cool side and hover in the 50s all day. Clearing skies, light winds and cool high pressure will probably send Sat morning lows to freezing or below.....with a good chance for a frost. Saturday - Sunday: Should be a rather benign weekend with weak ridging aloft translating eastward and surface pressure falls across the plains generating a southerly breeze. Should be a very pleasant weekend with above average temperatures. Sunday night - Wednesday: Looks like an unsettled pattern. Southwesterly flow sets up with the passage of the upper ridge allowing for increasing moist warm air advection. Considerable model uncertainty on PoPs and timing of the next cold front. GFS is much faster and brings a cold front through Monday night in response to a fast moving shortwave coming out of the desert southwest on Monday whereas the 12z ECMWF shows no sign of this wave...maybe A poor reflection by 12z Tuesday. In any event, there is the potential for a couple pieces of weak energy to be embedded within the southwesterly flow and give us a chance for some convection. Temperatures are likely to remain above average for the first part of the week. && .AVIATION...(For the 00Z TAFS through 00Z Thursday Evening) Issued at 634 PM CDT WED APR 1 2015 Storms erupting along a front over Nebraska will reach their peak intensity over the next few hours, then weaken quite a bit before they reach the KS/MO area early Thurs morning. Still expect about a 2-3 hour window of rain/isolated thunderstorms as the front moves through. Winds will likely remain elevated overnight ahead of the front with occasional gusts to 25 mph. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...MJ AVIATION...Hawblitzel
AREA FORECAST DISCUSSION
NWS BILLINGS MT
241 PM MDT TUE MAR 31 2015 .SHORT TERM...VALID FOR WED AND THU... AREAS OF FAIRLY THICK HIGH CLOUD HAVE KEPT OUR TEMPS AND MIXED WINDS A BIT IN CHECK SO FAR THIS AFTERNOON...THOUGH AS OF 2 PM TEMPS ARE IN THE UPPER 60S TO MID 70S. LATEST VISIBLE IMAGERY SHOWS MTN WAVE CLOUDS CONTINUING TO DEVELOP IN THE LEE OF THE BEARTOOTH ABSAROKAS IN SW FLOW ALOFT. THIS COULD HINDER OUR PREFRONTAL TSTM POTENTIAL AS WELL...BUT WILL SUSTAIN ISOLD WORDING INTO THE EVENING AS THE HRRR AND NAM HAVE BEEN HINTING AT. LOOKING WEST...COLD FRONT IS CURRENTLY A LITTLE EAST OF MISSOULA WITH PRESSURE FALLS IN EXCESS OF 1MB/HR NOTED FROM SALMON TO BUTTE AND HELENA. SOME WEAK CONVECTION IS TRYING TO DEVELOP IN THIS AREA. FRONT WILL PUSH INTO OUR WEST THIS EVENING. TIMING DEPICTED BY MODELS IS A BIT SLOWER THAN PREVIOUSLY THOUGHT THOUGH PRESSURE FIELDS ARE SOMEWHAT MUDDLED BY THE CONVECTION. H3 JET IS PARALLEL TO FRONT IN CENTRAL MT WITH PRESSURE FALLS AS ALREADY MENTIONED...AND IN FACT PRESSURE RISES ARE ALL THE WAY BACK IN OREGON NOW...SO A SLIGHTLY SLOWER FROPA TIMING SEEMS REASONABLE. EXPECT A FRONT TO LIVINGSTON BY AROUND 02Z...BILLINGS 04Z AND MILES CITY/SHERIDAN 06Z. W-NW WIND GUSTS TO 40 MPH WILL ACCOMPANY AND FOLLOW THIS FROPA. COULD SEE A LITTLE POST FRONTAL SHOWER ACTIVITY ESPECIALLY CONSIDERING THE MID LEVEL INSTABILITY. BEST CHANCE OF SHOWERS WILL BE OVER OUR WESTERN HIGH TERRAIN AS SECONDARY PV MAX MOVES IN FROM THE WEST. THE BEARTOOTH ABSAROKAS WILL SEE A LITTLE SNOWFALL AS 700MB TEMPS FALL TO NEAR -12C BY 12Z WEDNESDAY. LIVINGSTON MAY ALSO WET BULB DOWN TO A RAIN/SNOW SHOWER MIX BY LATE TONIGHT. AS FOR THE RED FLAG WARNING WILL MAKE NO CHANGES AT THIS TIME. FRONTAL PASSAGE AND WIND SHIFT TONIGHT WILL BE FOLLOWED BY GUSTY W-NW WINDS THROUGH TOMORROW WITH GUSTS OF 35-50 MPH. WE WILL BE VERY WELL-MIXED ON WEDNESDAY AND PER VERY DRY MID LEVELS EXPECT SFC DEWPTS TO REALLY CRASH...PROBABLY SINGLE DIGITS FROM BILLINGS WEST...RESULTING IN TEENS FOR AFTERNOON HUMIDITY DESPITE THE MUCH COOLER AIRMASS. WINDS WILL BEGIN TO DIMINISH AND RHS WILL BEGIN TO RECOVER WEDNESDAY NIGHT. UNSTABLE NW FLOW ON TAP FOR THURSDAY AS UPPER TROF SLIDES TO OUR EAST. SFC HIGH PUSHING INTO THE NORTHERN PLAINS WILL ACTUALLY STABILIZE THE AIRMASS IN OUR EAST ON THURSDAY...BUT LIFTED INDICES NEAR ZERO EXPECTED WEST OF BILLINGS. THIS ALONG WITH CONVERGENT BOUNDARY LAYER FLOW WILL ALLOW FOR A GREATER CHANCE OF RAIN/SNOW SHOWERS FROM BILLINGS WEST THURSDAY AFTERNOON AND EVENING. MTNS WILL SEE A LITTLE MORE SNOW ACCUMULATION. HIGHS IN THE 50S WEDNESDAY SHOULD FALL TO THE MID 40S TO LOWER 50S ON THURSDAY AS WE CONTINUE TO WEAKLY COLD ADVECT AS THE FLOW TURNS NORTHWESTERLY. A GOOD CHANCE OF BELOW FREEZING TEMPS MANY AREAS THURSDAY NIGHT. JKL .LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE... THE PATTERN FOR THE EXTENDED PERIOD IS SHAPING UP TO BE COOLER AND MORE UNSETTLED THAN THE PATTERN OF RECENT DAYS. A SHORTWAVE RIDGE WILL BE OVER THE AREA FRI AND FRI NIGHT. A DEPARTING SHORTWAVE OVER E MT WILL BRING A SLIGHT CHANCE OF SHOWERS TO THAT AREA ON FRI. FRI WILL HAVE HIGHS IN THE 50S UNDER A COOLER AIRMASS. THE RIDGE WILL FLATTEN ON SAT ALLOWING PACIFIC ENERGY TO MOVE INTO THE AREA. A COLD FRONT WILL PUSH S THROUGH THE REGION. TEMPERATURES WERE SOMEWHAT UNCERTAIN DUE TO FRONTAL TIMING DIFFERENCES BETWEEN THE MODELS. MODEL COMPROMISE GAVE HIGHS IN THE 50S TO AROUND 60 DEGREES. SW FLOW WILL APPROACH THE AREA SAT NIGHT AND WILL MOVE OVER THE AREA ON SUN. CHANCES FOR SHOWERS WILL BE CONFINED TO MAINLY WESTERN AND CENTRAL AREAS SAT THROUGH SUN. HIGHS ON SUN WILL BE SLIGHTLY LOWER...IN THE UPPER 40S AND 50S. FOR SUN NIGHT THROUGH TUE...MODELS AGREED ON AN UPPER TROUGH MOVING THROUGH THE REGION. MODELS HAD DRY-SLOTTING PUSHING UP INTO THE AREA FROM LOW PRESSURE IN WY SUN NIGHT INTO MON. CONTINUED CHANCE POPS OVER MOST OF THE AREA DURING THIS TIME...BUT THE DRY SLOT WILL NEED TO BE WATCHED IN CASE POPS ARE A BIT TOO HIGH. CONTINUED SLIGHT CHANCE/CHANCE POPS OVER THE AREA THROUGH THE REST OF THE PERIOD. HAD HIGHS IN THE 50S FOR MON AND TUE. TUE LOOKS A LITTLE WARMER THAN MON DUE TO THE DEPARTING SYSTEM. ARTHUR && .AVIATION... GUSTY WSW SURFACE WINDS WILL CONTINUE THIS AFTERNOON AHEAD OF A COLD FRONT. THE COLD FRONT WILL CROSS KLVM AROUND 02Z...KBIL AROUND 04Z...KMLS AROUND 06Z AND KSHR AROUND 05Z. SURFACE WINDS WILL SHIFT TO THE NW BEHIND THE FRONT WITH GUSTS OF 25 TO 35 KT. WINDS WILL GUST IN THE 30S AND 40S FROM THE NW ON WED. OTHERWISE...THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS AROUND KLVM...AND OVER AND NEAR THE WESTERN MOUNTAINS AFTER 21Z TODAY. WIDELY SCATTERED TO SCATTERED SHOWERS AND A FEW EVENING THUNDERSTORMS WILL OCCUR OVER THE AREA TONIGHT WITH POSSIBLE MVFR CONDITIONS. THERE WILL BE A CHANCE OF SHOWERS OVER AND NEAR THE MOUNTAINS ON WED. LOCALIZED TO AREAS OF MOUNTAIN OBSCURATION THIS AFTERNOON WILL INCREASE OVERNIGHT AND PERSIST ON WED. ARTHUR && .PRELIMINARY POINT TEMP/POPS... WED THU FRI SAT SUN MON TUE ----------------------------------------------------------- BIL 042/056 033/049 031/056 033/059 034/056 035/055 033/056 31/N 13/W 31/B 01/B 22/W 33/W 32/W LVM 035/050 027/047 025/053 031/054 028/052 030/050 028/052 54/W 24/W 31/B 12/W 23/W 33/W 32/W HDN 040/058 030/050 028/058 030/062 033/059 034/058 031/059 31/N 12/W 21/B 01/B 21/B 22/W 32/W MLS 041/058 031/049 028/055 030/060 032/058 033/055 031/055 21/N 02/W 12/W 01/B 11/B 33/W 32/W 4BQ 041/057 031/048 025/054 028/061 031/058 032/057 031/057 21/N 02/W 11/B 01/B 12/W 22/W 32/W BHK 039/056 029/045 024/052 026/058 028/054 028/049 028/050 21/N 02/W 12/W 01/B 11/B 33/W 32/W SHR 037/054 028/047 025/052 026/059 029/057 032/055 030/055 22/W 13/W 21/B 01/B 12/W 22/W 32/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...RED FLAG WARNING IN EFFECT UNTIL 9 PM MDT WEDNESDAY FOR ZONES 28>42-56>58-63>68. WY...RED FLAG WARNING IN EFFECT UNTIL 9 PM MDT WEDNESDAY FOR ZONES 98-99. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
238 PM MDT TUE MAR 31 2015 .SHORT TERM...VALID FOR WED AND THU... AREAS OF FAIRLY THICK HIGH CLOUD HAVE KEPT OUR TEMPS AND MIXED WINDS A BIT IN CHECK SO FAR THIS AFTERNOON...THOUGH AS OF 2 PM TEMPS ARE IN THE UPPER 60S TO MID 70S. LATEST VISIBLE IMAGERY SHOWS MTN WAVE CLOUDS CONTINUING TO DEVELOP IN THE LEE OF THE BEARTOOTH ABSAROKAS IN SW FLOW ALOFT. THIS COULD HINDER OUR PREFRONTAL TSTM POTENTIAL AS WELL...BUT WILL SUSTAIN ISOLD WORDING INTO THE EVENING AS THE HRRR AND NAM HAVE BEEN HINTING AT. LOOKING WEST...COLD FRONT IS CURRENTLY A LITTLE EAST OF MISSOULA WITH PRESSURE FALLS IN EXCESS OF 1MB/HR NOTED FROM SALMON TO BUTTE AND HELENA. SOME WEAK CONVECTION IS TRYING TO DEVELOP IN THIS AREA. FRONT WILL PUSH INTO OUR WEST THIS EVENING. TIMING DEPICTED BY MODELS IS A BIT SLOWER THAN PREVIOUSLY THOUGHT THOUGH PRESSURE FIELDS ARE SOMEWHAT MUDDLED BY THE CONVECTION. H3 JET IS PARALLEL TO FRONT IN CENTRAL MT WITH PRESSURE FALLS AS ALREADY MENTIONED...AND IN FACT PRESSURE RISES ARE ALL THE WAY BACK IN OREGON NOW...SO A SLIGHTLY SLOWER FROPA TIMING SEEMS REASONABLE. EXPECT A FRONT TO LIVINGSTON BY AROUND 02Z...BILLINGS 04Z AND MILES CITY/SHERIDAN 06Z. W-NW WIND GUSTS TO 40 MPH WILL ACCOMPANY AND FOLLOW THIS FROPA. COULD SEE A LITTLE POST FRONTAL SHOWER ACTIVITY ESPECIALLY CONSIDERING THE MID LEVEL INSTABILITY. BEST CHANCE OF SHOWERS WILL BE OVER OUR WESTERN HIGH TERRAIN AS SECONDARY PV MAX MOVES IN FROM THE WEST. THE BEARTOOTH ABSAROKAS WILL SEE A LITTLE SNOWFALL AS 700MB TEMPS FALL TO NEAR -12C BY 12Z WEDNESDAY. LIVINGSTON MAY ALSO WET BULB DOWN TO A RAIN/SNOW SHOWER MIX BY LATE TONIGHT. AS FOR THE RED FLAG WARNING WILL MAKE NO CHANGES AT THIS TIME. FRONTAL PASSAGE AND WIND SHIFT TONIGHT WILL BE FOLLOWED BY GUSTY W-NW WINDS THROUGH TOMORROW WITH GUSTS OF 35-50 MPH. WE WILL BE VERY WELL-MIXED ON WEDNESDAY AND PER VERY DRY MID LEVELS EXPECT SFC DEWPTS TO REALLY CRASH...PROBABLY SINGLE DIGITS FROM BILLINGS WEST...RESULTING IN TEENS FOR AFTERNOON HUMIDITY DESPITE THE MUCH COOLER AIRMASS. WINDS WILL BEGIN TO DIMINISH AND RHS WILL BEGIN TO RECOVER WEDNESDAY NIGHT. UNSTABLE NW FLOW ON TAP FOR THURSDAY AS UPPER TROF SLIDES TO OUR EAST. SFC HIGH PUSHING INTO THE NORTHERN PLAINS WILL ACTUALLY STABILIZE THE AIRMASS IN OUR EAST ON THURSDAY...BUT LIFTED INDICES NEAR ZERO EXPECTED WEST OF BILLINGS. THIS ALONG WITH CONVERGENT BOUNDARY LAYER FLOW WILL ALLOW FOR A GREATER CHANCE OF RAIN/SNOW SHOWERS FROM BILLINGS WEST THURSDAY AFTERNOON AND EVENING. MTNS WILL SEE A LITTLE MORE SNOW ACCUMULATION. HIGHS IN THE 50S WEDNESDAY SHOULD FALL TO THE MID 40S TO LOWER 50S ON THURSDAY AS WE CONTINUE TO WEAKLY COLD ADVECT AS THE FLOW TURNS NORTHWESTERLY. A GOOD CHANCE OF BELOW FREEZING TEMPS MANY AREAS THURSDAY NIGHT. JKL .LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE... THE PATTERN FOR THE EXTENDED PERIOD IS SHAPING UP TO BE COOLER AND MORE UNSETTLED THAN THE PATTERN OF RECENT DAYS. A SHORTWAVE RIDGE WILL BE OVER THE AREA FRI AND FRI NIGHT. A DEPARTING SHORTWAVE OVER E MT WILL BRING A SLIGHT CHANCE OF SHOWERS TO THAT AREA ON FRI. FRI WILL HAVE HIGHS IN THE 50S UNDER A COOLER AIRMASS. THE RIDGE WILL FLATTEN ON SAT ALLOWING PACIFIC ENERGY TO MOVE INTO THE AREA. A COLD FRONT WILL PUSH S THROUGH THE REGION. TEMPERATURES WERE SOMEWHAT UNCERTAIN DUE TO FRONTAL TIMING DIFFERENCES BETWEEN THE MODELS. MODEL COMPROMISE GAVE HIGHS IN THE 50S TO AROUND 60 DEGREES. SW FLOW WILL APPROACH THE AREA SAT NIGHT AND WILL MOVE OVER THE AREA ON SUN. CHANCES FOR SHOWERS WILL BE CONFINED TO MAINLY WESTERN AND CENTRAL AREAS SAT THROUGH SUN. HIGHS ON SUN WILL BE SLIGHTLY LOWER...IN THE UPPER 40S AND 50S. FOR SUN NIGHT THROUGH TUE...MODELS AGREED ON AN UPPER TROUGH MOVING THROUGH THE REGION. MODELS HAD DRY-SLOTTING PUSHING UP INTO THE AREA FROM LOW PRESSURE IN WY SUN NIGHT INTO MON. CONTINUED CHANCE POPS OVER MOST OF THE AREA DURING THIS TIME...BUT THE DRY SLOT WILL NEED TO BE WATCHED IN CASE POPS ARE A BIT TOO HIGH. CONTINUED SLIGHT CHANCE/CHANCE POPS OVER THE AREA THROUGH THE REST OF THE PERIOD. HAD HIGHS IN THE 50S FOR MON AND TUE. TUE LOOKS A LITTLE WARMER THAN MON DUE TO THE DEPARTING SYSTEM. ARTHUR && .AVIATION... GUSTY WSW SURFACE WINDS WILL CONTINUE THIS AFTERNOON AHEAD OF A COLD FRONT. THE COLD FRONT WILL CROSS KLVM AROUND 02Z...KBIL AROUND 04Z...KMLS AROUND 06Z AND KSHR AROUND 05Z. SURFACE WINDS WILL SHIFT TO THE NW BEHIND THE FRONT WITH GUSTS OF 25 TO 35 KT. WINDS WILL GUST IN THE 30S AND 40S FROM THE NW ON WED. OTHERWISE...THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS AROUND KLVM...AND OVER AND NEAR THE WESTERN MOUNTAINS AFTER 21Z TODAY. WIDELY SCATTERED TO SCATTERED SHOWERS AND A FEW EVENING THUNDERSTORMS WILL OCCUR OVER THE AREA TONIGHT WITH POSSIBLE MVFR CONDITIONS. THERE WILL BE A CHANCE OF SHOWERS OVER AND NEAR THE MOUNTAINS ON WED. LOCALIZED TO AREAS OF MOUNTAIN OBSCURATION THIS AFTERNOON WILL INCREASE OVERNIGHT AND PERSIST ON WED. ARTHUR && .PRELIMINARY POINT TEMP/POPS... WED THU FRI SAT SUN MON TUE ----------------------------------------------------------- BIL 042/055 033/049 031/056 033/059 034/056 035/055 033/056 31/N 13/W 31/B 01/B 22/W 33/W 32/W LVM 035/050 027/047 025/053 031/054 028/052 030/050 028/052 54/W 24/W 31/B 12/W 23/W 33/W 32/W HDN 040/058 030/050 028/058 030/062 033/059 034/058 031/059 31/N 12/W 21/B 01/B 21/B 22/W 32/W MLS 041/058 031/049 028/055 030/060 032/058 033/055 031/055 21/N 02/W 12/W 01/B 11/B 33/W 32/W 4BQ 041/057 031/048 025/054 028/061 031/058 032/057 031/057 21/N 02/W 11/B 01/B 12/W 22/W 32/W BHK 039/056 029/045 024/052 026/058 028/054 028/049 028/050 21/N 02/W 12/W 01/B 11/B 33/W 32/W SHR 037/053 028/047 025/052 026/059 029/057 032/055 030/055 22/W 13/W 21/B 01/B 12/W 22/W 32/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...RED FLAG WARNING IN EFFECT UNTIL 9 PM MDT WEDNESDAY FOR ZONES 28>42-56>58-63>68. WY...RED FLAG WARNING IN EFFECT UNTIL 9 PM MDT WEDNESDAY FOR ZONES 98-99. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
630 PM CDT WED APR 1 2015 .UPDATE... ISSUED AT 625 PM CDT WED APR 1 2015 SEVERE WATCH 15 WAS ISSUED EARLIER VALID UNTIL 06Z. STORMS ALONG THE COLD FRONT IN NORTHEAST NEBRASKA HAVE PRODUCED UP TO QUARTER SIZE HAIL AND WIND GUSTS UP TO 50 MPH. BELIEVE THIS MAY TRANSITION INTO MORE OF A WIND EVENT AS WE HEAD THROUGH THE EVENING. && .SHORT TERM...(TONIGHT THROUGH SATURDAY) ISSUED AT 241 PM CDT WED APR 1 2015 MAIN FOCUS IS ON THE DEVELOPING SEVERE WEATHER THREAT AS A COLD FRONT MOVES INTO THE REGION THIS AFTERNOON. THE COLD FRONT AT 19Z WAS LOCATED FROM EAST CENTRAL SD THROUGH NORTHWEST KANSAS...WITH SOME MINIMAL DEVELOPING ALONG THE COLD FRONT ACROSS WESTERN THROUGH NORTH CENTRAL NEBRASKA. HRRR MODEL HAS INDICATED CONVECTION MAY DEVELOP ALONG THE FRONT INTO ANTELOPE/KNOX COUNTIES BY 21Z...BUT THIS STILL SEEMS ABOUT 1 HOUR TOO SOON...DEFINITELY PREFERRING THE 12Z HIRES NMM/ARW AND 00Z SPC SSEO MODELS SUGGESTING DEVELOPMENT MAY HOLD OFF UNTIL 22-23Z. MEANWHILE...THE MOISTURE RETURN HAS STRUGGLED IN OUR AREA...FIRST BEING IMPEDED BY OVERNIGHT CONVECTION TO OUR SOUTH...AND NOW SURFACE DEWPOINTS HAVE BEEN MIXING DOWN DESPITE THE STRONG SOUTHERLY WINDS...WHICH AT TIMES HAVE MET WIND ADVISORY CRITERIA ACROSS THE NORTHERN HALF OF THE FORECAST AREA. THE COMBINATION OF TEMPS IN THE LOWER 80S AND STRONG WINDS HAS LED TO VERY HIGH DANGER AS WELL. LOW 50S DEWPOINTS HAVE REACHED NORTHEAST KANSAS AND SOUTHWEST IOWA THOUGH...WE SHOULD SEE DEWPOINTS RECOVER INTO THE 50S THIS EVENING AS TEMPS COOL. BULK WIND SHEAR IS NOT THAT IMPRESSIVE AT 30-35 KNOTS INITIALLY... BUT SHOULD INCREASE TO 40 TO 50 KNOTS THROUGH THE EVENING. LOW LEVEL JET SHOULD ALSO STRENGTHEN WHICH MAY HELP BOOST STORM POTENTIAL THROUGH THE EVENING...ALTHOUGH THE LATER INTO THE EVENING...THEN INSTABILITY BEGINS TO WANE A BIT. FEELING IS THAT STORMS WILL DEVELOP IN NORTHEAST NEBRASKA BY 22-23Z...THEN DEVELOP INTO MORE OF A LINER CLUSTER OF STORMS THAT THEN MOVE ACROSS THE FORECAST AREA THROUGH THE EVENING...AND OUT OF THE AREA BY DAYBREAK THURSDAY. STORMS PROBABLY DON`T REACH LINCOLN UNTIL 8-9 PM AND OMAHA 9-10 PM...AND SOUTHEAST NE AND SOUTHWEST IA EVEN LATER. SOME AREAS COULD GET AROUND AN INCH OF RAIN PLUS OR MINUS...BUT STILL WELL WITHIN 3 HOURLY FLASH FLOOD GUIDANCE VALUES OF JUST OVER 2 INCHES. DRY AND COOLER BUT STILL ABOVE NORMAL WEATHER EXPECTED FOR THURSDAY. ANOTHER WEAK WAVE MOVES OUT OF THE CENTRAL ROCKIES THURSDAY NIGHT WHICH COULD BRING A FEW SHOWERS TO THE SOUTHERN HALF OF THE FORECAST AREA...THEN EVEN COOLER FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. SATURDAY SHOULD BE ANOTHER BEAUTIFUL DAY WITH TEMPS BACK INTO THE MID/UPPER 60S WITH BREEZY CONDITIONS DEVELOPING. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 241 PM CDT WED APR 1 2015 EASTER SUNDAY SHOULD ALSO BE ANOTHER BEAUTIFUL DAY WITH LOTS OF SUNSHINE AND TEMPS IN THE UPPER 60S. AS WEAK SOUTHWEST FLOW ALOFT REDEVELOPS LATE IN THE WEEKEND THROUGH EARLY NEXT WEEK...THERE COULD BE ISOLATED CHANCES FOR SHOWERS/STORMS SUNDAY NIGHT THROUGH ABOUT TUESDAY...ALTHOUGH THERE ARE SOME MODEL DISCREPANCIES BETWEEN GFS/ECMWF AND THUS CONFIDENCE IS LOW ON THE DETAILS AT THIS TIME. && .AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 625 PM CDT WED APR 1 2015 COLD FRONT AND ASSOCIATED SEVERE STORMS WERE LOCATED OVER KOFK AT TAF ISSUANCE. STORMS WILL PROBABLY BE EAST OF KOFK BY 01Z. KLNK/KOMA WELL AHEAD OF THE COLD FRONT AT TAF ISSUANCE WITH VFR CONDITIONS...BUT WITH SOUTHERLY WINDS AT 20 GUSTING TO 30 KNOTS. STORMS ARRIVE AT KLNK BY 03Z AND KOMA BY 04Z. STORMS AFFECT THESE TWO LOCATIONS THROUGH ABOUT 08-09Z...THEN VFR AFTERWARD. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...DEWALD SHORT TERM...DEWALD LONG TERM...DEWALD AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
945 PM CDT WED APR 1 2015 .UPDATE... ISSUED AT 945 PM CDT WED APR 1 2015 HAVE CANCELLED THE RED FLAG WARNING THAT WAS IN EFFECT UNTIL 10 PM CENTRAL THIS EVENING. A FIRE WEATHER WATCH REMAINS IN EFFECT FOR THURSDAY MORNING THROUGH THURSDAY EVENING FOR PORTIONS OF SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA. WINDS HAVE DIMINISHED THIS EVENING WITH SKIES BECOMING CLEAR TO PARTLY CLOUDY. THERE ARE A FEW MID CLOUDS AND POSSIBLY A SPRINKLE OR TWO ALONG THE INTERNATIONAL BORDER TRACKING FROM NORTHWEST INTO NORTH CENTRAL NORTH DAKOTA. NOT SIGNIFICANT ENOUGH TO ADD A MENTION OF SHOWERS. THE NEXT CHANCE OF RAIN OR SNOW WILL BE LATE TONIGHT INTO THURSDAY AS WRAP AROUND MOISTURE ASSOCIATED WITH A SYSTEM IN SOUTHERN CANADA DROPS SOUTH INTO WESTERN AND CENTRAL NORTH DAKOTA. WINDS WILL ALSO INCREASE AGAIN BEGINNING LATE TONIGHT ACROSS THE NORTH AND ACROSS THE ENTIRE FORECAST AREA ON THURSDAY. STRONGEST WINDS ALOFT ARE EXPECTED TO BE DURING THE MORNING HOURS ON THURSDAY...WITH BETTER MIXING IN THE AFTERNOON BUT WINDS ALOFT WILL BE DIMINISHING. WILL NEED TO MONITOR FOR POSSIBLE WIND HIGHLIGHTS. UPDATE ISSUED AT 822 PM CDT WED APR 1 2015 QUICK UPDATED TO EXPIRE THE WIND ADVISORY. WINDS HAVE DIMINISHED SUBSTANTIALLY DURING THE PAST HOUR. ADVISORY WINDS ARE NO LONGER ANTICIPATED THIS EVENING. UPDATE ISSUED AT 643 PM CDT WED APR 1 2015 STRONG WEST TO NORTHWEST WINDS ARE EXPECTED TO DIMINISH BELOW ADVISORY CRITERIA OVER THE NEXT HOUR OR TWO AS WE LOSE OUR DAYTIME HEATING. WILL STILL BE BREEZY THIS EVENING WITH WINDS PICKING UP AGAIN ACROSS THE NORTH LATER TONIGHT...AND ANOTHER WINDY DAY EXPECTED ON THURSDAY. MADE SOME MINOR ADJUSTMENTS TO SKY COVER. ALSO ADJUSTED DEW POINTS LOWER OVER THE SOUTHWEST USED A COMBINATION OF CURRENT FORECAST WITH THE LATEST RAP SURFACE DEW POINTS. THIS IS STILL GIVING SUB 20 PERCENT RH VALUES OVER THE FAR SOUTHWEST. IN ADDITION...WITH SURFACE WINDS STILL STRONG OVER THE FORECAST AREA WILL CONTINUE THE RED FLAG WARNING FOR NOW...WHICH EXPIRES AT 10 PM CENTRAL. WILL TAKE A LOOK AT WINDS OVER THE NEXT HOUR TO SEE IF WE CAN LET THE WIND ADVISORY EXPIRE AT 8 PM. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 346 PM CDT WED APR 1 2015 CURRENT SURFACE ANALYSIS PLACES COLD FRONT PUSHING THROUGH THE RED RIVER VALLEY WITH GUSTY WINDS OVER WESTERN THROUGH CENTRAL NORTH DAKOTA IN ITS WAKE. UPPER LEVEL ANALYSIS PLACES LOW ROTATING NEAR THE ALBERTA/SASKATCHEWAN BORDER WITH SOUTHWESTERLY FLOW OVER OUR AREA. FOR TONIGHT...WINDS WILL DIMINISH A BIT OVERNIGHT THOUGH STILL WILL REMAIN A BIT GUSTY AS PRESSURE GRADIENT REMAINS A BIT TIGHT. OTHERWISE...MAINLY QUIET WEATHER EXPECTED UNTIL TOWARDS MORNING WHEN SHORT WAVE SWINGING AROUND EASTERLY MOVING UPPER LOW NUDGES INTO THE AREA BRINGING LOW PRECIPITATION CHANCES TO THE NORTHWEST. ON THURSDAY...WAVE CONTINUES TO PUSH THROUGH THE AREA BRINGING PRECIPITATION CHANCES OVER THE NORTHERN AND CENTRAL PORTIONS OF THE AREA. THE MAIN CONCERN WITH THIS WILL BE INCREASING WINDS WITH THE NEXT ROUND OF COLD AIR ADVECTION WITH THE SYSTEM. WILL HAVE TO RE-EVALUATE ON LATER SHIFTS TO SEE IF ANOTHER ROUND OF WIND HEADLINES ARE NEEDED. RELATIVE HUMIDITY LEVELS WILL AGAIN BE ON THE LOW SIDE OVER THE SOUTH WHICH WILL COMBINE WITH THE WINDS TO BRING ANOTHER DAY OF FIRE CONCERNS (PLEASE SEE FIRE WEATHER DISCUSSION BELOW). .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 346 PM CDT WED APR 1 2015 AS AN UPPER LOW CONTINUES TO VACATE THE REGION...WINDS WILL BEGIN TO RELAX ON THURSDAY EVENING INTO THE OVERNIGHT HOURS. TEMPERATURES WILL REMAIN NEAR NORMAL FOR THIS TIME OF YEAR...WITH A SLIGHT WARM UP ON FRIDAY AND SATURDAY BEFORE A COOLING TREND BEGINS ON SUNDAY. THE EXTENDED RANGE FEATURES NUMEROUS EMBEDDED IMPULSES WITHIN A FAIRLY ZONAL PATTERN...AND LIGHT PRECIPITATION CHANCES WILL BE POSSIBLE FRIDAY THROUGH SUNDAY. THE GFS AND ECMWF ARE HINTING AT A MORE SIGNIFICANT STORM IN THE MONDAY AND TUESDAY TIME FRAME...BUT QUITE A BIT OF UNCERTAINTY REMAINS AS FAR AS PRECIPITATION TYPE...TIMING...TRACK...AND INTENSITY. WILL HAVE TO KEEP AN EYE ON MODEL TRENDS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 945 PM CDT WED APR 1 2015 STRONG WEST TO NORTHWEST WINDS HAVE DIMINISHED THIS EVENING...BUT WILL PICK UP AGAIN FROM NORTH TO SOUTH LATE TONIGHT THROUGH THURSDAY. EXPECT NORTHWEST WINDS 20 TO 30 MPH WITH GUSTS OVER 40 MPH LATE THURSDAY MORNING THROUGH THURSDAY AFTERNOON AT ALL TAF SITES. MOISTURE WRAPPING AROUND A LOW PRESSURE SYSTEM OVER SOUTHERN CANADA WILL DROP SOUTH INTO NORTH DAKOTA LATE TONIGHT AND THURSDAY. THIS WILL BRING THE POSSIBILITY OF MVFR CEILINGS AND SCATTERED RAIN AND SNOW SHOWERS. FOR NOW KEPT THE MENTION OF MVFR CEILINGS AND A VCSH ACROSS THE NORTH INCLUDING KISN AND KMOT. NOT AS CONFIDENT AT THIS TIME WITH MVFR CEILINGS REACHING THE SOUTHERN TAF SITES. && .FIRE WEATHER... ISSUED AT 346 PM CDT WED APR 1 2015 GUSTY WESTERLY WINDS WILL CONTINUE TO BRING CRITICAL FIRE WEATHER CONDITIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA INTO THIS EVENING. WINDS WILL DIMINISH SLIGHTLY OVERNIGHT...AND WILL INCREASE AGAIN ON THURSDAY. OVER PORTIONS OF SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA THE GUSTY WINDS WILL AGAIN COMBINE WITH RELATIVE HUMIDITY VALUES AS LOW AS 30 PERCENT TO POSSIBLY BRING ANOTHER DAY OF CRITICAL FIRE WEATHER CONDITIONS. A FIRE WEATHER WATCH HAS BEEN POSTED OVER THIS AREA FOR THURSDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR NDZ040>046. && $$ UPDATE...TWH SHORT TERM...JJS LONG TERM...ZH AVIATION...TWH FIRE WEATHER...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
822 PM CDT WED APR 1 2015 .UPDATE... ISSUED AT 822 PM CDT WED APR 1 2015 QUICK UPDATED TO EXPIRE THE WIND ADVISORY. WINDS HAVE DIMINISHED SUBSTANTIALLY DURING THE PAST HOUR. ADVISORY WINDS ARE NO LONGER ANTICIPATED THIS EVENING. UPDATE ISSUED AT 643 PM CDT WED APR 1 2015 STRONG WEST TO NORTHWEST WINDS ARE EXPECTED TO DIMINISH BELOW ADVISORY CRITERIA OVER THE NEXT HOUR OR TWO AS WE LOSE OUR DAYTIME HEATING. WILL STILL BE BREEZY THIS EVENING WITH WINDS PICKING UP AGAIN ACROSS THE NORTH LATER TONIGHT...AND ANOTHER WINDY DAY EXPECTED ON THURSDAY. MADE SOME MINOR ADJUSTMENTS TO SKY COVER. ALSO ADJUSTED DEW POINTS LOWER OVER THE SOUTHWEST USED A COMBINATION OF CURRENT FORECAST WITH THE LATEST RAP SURFACE DEW POINTS. THIS IS STILL GIVING SUB 20 PERCENT RH VALUES OVER THE FAR SOUTHWEST. IN ADDITION...WITH SURFACE WINDS STILL STRONG OVER THE FORECAST AREA WILL CONTINUE THE RED FLAG WARNING FOR NOW...WHICH EXPIRES AT 10 PM CENTRAL. WILL TAKE A LOOK AT WINDS OVER THE NEXT HOUR TO SEE IF WE CAN LET THE WIND ADVISORY EXPIRE AT 8 PM. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 346 PM CDT WED APR 1 2015 CURRENT SURFACE ANALYSIS PLACES COLD FRONT PUSHING THROUGH THE RED RIVER VALLEY WITH GUSTY WINDS OVER WESTERN THROUGH CENTRAL NORTH DAKOTA IN ITS WAKE. UPPER LEVEL ANALYSIS PLACES LOW ROTATING NEAR THE ALBERTA/SASKATCHEWAN BORDER WITH SOUTHWESTERLY FLOW OVER OUR AREA. FOR TONIGHT...WINDS WILL DIMINISH A BIT OVERNIGHT THOUGH STILL WILL REMAIN A BIT GUSTY AS PRESSURE GRADIENT REMAINS A BIT TIGHT. OTHERWISE...MAINLY QUIET WEATHER EXPECTED UNTIL TOWARDS MORNING WHEN SHORT WAVE SWINGING AROUND EASTERLY MOVING UPPER LOW NUDGES INTO THE AREA BRINGING LOW PRECIPITATION CHANCES TO THE NORTHWEST. ON THURSDAY...WAVE CONTINUES TO PUSH THROUGH THE AREA BRINGING PRECIPITATION CHANCES OVER THE NORTHERN AND CENTRAL PORTIONS OF THE AREA. THE MAIN CONCERN WITH THIS WILL BE INCREASING WINDS WITH THE NEXT ROUND OF COLD AIR ADVECTION WITH THE SYSTEM. WILL HAVE TO RE-EVALUATE ON LATER SHIFTS TO SEE IF ANOTHER ROUND OF WIND HEADLINES ARE NEEDED. RELATIVE HUMIDITY LEVELS WILL AGAIN BE ON THE LOW SIDE OVER THE SOUTH WHICH WILL COMBINE WITH THE WINDS TO BRING ANOTHER DAY OF FIRE CONCERNS (PLEASE SEE FIRE WEATHER DISCUSSION BELOW). .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 346 PM CDT WED APR 1 2015 AS AN UPPER LOW CONTINUES TO VACATE THE REGION...WINDS WILL BEGIN TO RELAX ON THURSDAY EVENING INTO THE OVERNIGHT HOURS. TEMPERATURES WILL REMAIN NEAR NORMAL FOR THIS TIME OF YEAR...WITH A SLIGHT WARM UP ON FRIDAY AND SATURDAY BEFORE A COOLING TREND BEGINS ON SUNDAY. THE EXTENDED RANGE FEATURES NUMEROUS EMBEDDED IMPULSES WITHIN A FAIRLY ZONAL PATTERN...AND LIGHT PRECIPITATION CHANCES WILL BE POSSIBLE FRIDAY THROUGH SUNDAY. THE GFS AND ECMWF ARE HINTING AT A MORE SIGNIFICANT STORM IN THE MONDAY AND TUESDAY TIME FRAME...BUT QUITE A BIT OF UNCERTAINTY REMAINS AS FAR AS PRECIPITATION TYPE...TIMING...TRACK...AND INTENSITY. WILL HAVE TO KEEP AN EYE ON MODEL TRENDS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 822 PM CDT WED APR 1 2015 STRONG WEST TO NORTHWEST WINDS HAVE DIMINISHED THIS EVENING...BUT WILL PICK UP AGAIN FROM NORTH TO SOUTH LATE TONIGHT THROUGH THURSDAY. EXPECT NORTHWEST WINDS 20 TO 30 MPH WITH GUSTS OVER 40 MPH LATE THURSDAY MORNING THROUGH THURSDAY AFTERNOON AT ALL TAF SITES. MOISTURE WRAPPING AROUND A LOW PRESSURE SYSTEM OVER SOUTHERN CANADA WILL DROP SOUTH INTO NORTH DAKOTA LATE TONIGHT AND THURSDAY. THIS WILL BRING THE POSSIBILITY OF MVFR CEILINGS AND SCATTERED RAIN AND SNOW SHOWERS. FOR NOW KEPT THE MENTION OF MVFR CEILINGS AND A VCSH ACROSS THE NORTH INCLUDING KISN AND KMOT. NOT AS CONFIDENT AT THIS TIME WITH MVFR CEILINGS REACHING THE SOUTHERN TAF SITES. && .FIRE WEATHER... ISSUED AT 346 PM CDT WED APR 1 2015 GUSTY WESTERLY WINDS WILL CONTINUE TO BRING CRITICAL FIRE WEATHER CONDITIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA INTO THIS EVENING. WINDS WILL DIMINISH SLIGHTLY OVERNIGHT...AND WILL INCREASE AGAIN ON THURSDAY. OVER PORTIONS OF SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA THE GUSTY WINDS WILL AGAIN COMBINE WITH RELATIVE HUMIDITY VALUES AS LOW AS 30 PERCENT TO POSSIBLY BRING ANOTHER DAY OF CRITICAL FIRE WEATHER CONDITIONS. A FIRE WEATHER WATCH HAS BEEN POSTED OVER THIS AREA FOR THURSDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 10 PM CDT /9 PM MDT/ THIS EVENING FOR NDZ001>005-009>013-017>023-025-031>037-040>048-050-051. FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR NDZ040>046. && $$ UPDATE...TWH SHORT TERM...JJS LONG TERM...ZH AVIATION...TWH FIRE WEATHER...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
643 PM CDT WED APR 1 2015 .UPDATE... ISSUED AT 643 PM CDT WED APR 1 2015 STRONG WEST TO NORTHWEST WINDS ARE EXPECTED TO DIMINISH BELOW ADVISORY CRITERIA OVER THE NEXT HOUR OR TWO AS WE LOSE OUR DAYTIME HEATING. WILL STILL BE BREEZY THIS EVENING WITH WINDS PICKING UP AGAIN ACROSS THE NORTH LATER TONIGHT...AND ANOTHER WINDY DAY EXPECTED ON THURSDAY. MADE SOME MINOR ADJUSTMENTS TO SKY COVER. ALSO ADJUSTED DEW POINTS LOWER OVER THE SOUTHWEST USED A COMBINATION OF CURRENT FORECAST WITH THE LATEST RAP SURFACE DEW POINTS. THIS IS STILL GIVING SUB 20 PERCENT RH VALUES OVER THE FAR SOUTHWEST. IN ADDITION...WITH SURFACE WINDS STILL STRONG OVER THE FORECAST AREA WILL CONTINUE THE RED FLAG WARNING FOR NOW...WHICH EXPIRES AT 10 PM CENTRAL. WILL TAKE A LOOK AT WINDS OVER THE NEXT HOUR TO SEE IF WE CAN LET THE WIND ADVISORY EXPIRE AT 8 PM. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 346 PM CDT WED APR 1 2015 CURRENT SURFACE ANALYSIS PLACES COLD FRONT PUSHING THROUGH THE RED RIVER VALLEY WITH GUSTY WINDS OVER WESTERN THROUGH CENTRAL NORTH DAKOTA IN ITS WAKE. UPPER LEVEL ANALYSIS PLACES LOW ROTATING NEAR THE ALBERTA/SASKATCHEWAN BORDER WITH SOUTHWESTERLY FLOW OVER OUR AREA. FOR TONIGHT...WINDS WILL DIMINISH A BIT OVERNIGHT THOUGH STILL WILL REMAIN A BIT GUSTY AS PRESSURE GRADIENT REMAINS A BIT TIGHT. OTHERWISE...MAINLY QUIET WEATHER EXPECTED UNTIL TOWARDS MORNING WHEN SHORT WAVE SWINGING AROUND EASTERLY MOVING UPPER LOW NUDGES INTO THE AREA BRINGING LOW PRECIPITATION CHANCES TO THE NORTHWEST. ON THURSDAY...WAVE CONTINUES TO PUSH THROUGH THE AREA BRINGING PRECIPITATION CHANCES OVER THE NORTHERN AND CENTRAL PORTIONS OF THE AREA. THE MAIN CONCERN WITH THIS WILL BE INCREASING WINDS WITH THE NEXT ROUND OF COLD AIR ADVECTION WITH THE SYSTEM. WILL HAVE TO RE-EVALUATE ON LATER SHIFTS TO SEE IF ANOTHER ROUND OF WIND HEADLINES ARE NEEDED. RELATIVE HUMIDITY LEVELS WILL AGAIN BE ON THE LOW SIDE OVER THE SOUTH WHICH WILL COMBINE WITH THE WINDS TO BRING ANOTHER DAY OF FIRE CONCERNS (PLEASE SEE FIRE WEATHER DISCUSSION BELOW). .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 346 PM CDT WED APR 1 2015 AS AN UPPER LOW CONTINUES TO VACATE THE REGION...WINDS WILL BEGIN TO RELAX ON THURSDAY EVENING INTO THE OVERNIGHT HOURS. TEMPERATURES WILL REMAIN NEAR NORMAL FOR THIS TIME OF YEAR...WITH A SLIGHT WARM UP ON FRIDAY AND SATURDAY BEFORE A COOLING TREND BEGINS ON SUNDAY. THE EXTENDED RANGE FEATURES NUMEROUS EMBEDDED IMPULSES WITHIN A FAIRLY ZONAL PATTERN...AND LIGHT PRECIPITATION CHANCES WILL BE POSSIBLE FRIDAY THROUGH SUNDAY. THE GFS AND ECMWF ARE HINTING AT A MORE SIGNIFICANT STORM IN THE MONDAY AND TUESDAY TIME FRAME...BUT QUITE A BIT OF UNCERTAINTY REMAINS AS FAR AS PRECIPITATION TYPE...TIMING...TRACK...AND INTENSITY. WILL HAVE TO KEEP AN EYE ON MODEL TRENDS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 643 PM CDT WED APR 1 2015 STRONG WEST TO NORTHWEST WINDS WILL DIMINISH THIS EVENING...THEN PICK UP AGAIN FROM NORTH TO SOUTH LATE TONIGHT THROUGH THURSDAY. EXPECT NORTHWEST WINDS 20 TO 30 MPH WITH GUSTS OVER 40 MPH LATE THURSDAY MORNING THROUGH THURSDAY AFTERNOON AT ALL TAF SITES. MOISTURE WRAPPING AROUND A LOW PRESSURE SYSTEM OVER SOUTHERN CANADA WILL DROP SOUTH INTO NORTH DAKOTA LATE TONIGHT AND THURSDAY. THIS WILL BRING THE POSSIBILITY OF MVFR CEILINGS AND SCATTERED RAIN AND SNOW SHOWERS. FOR NOW KEPT THE MENTION OF MVFR CEILINGS AND A VCSH ACROSS THE NORTH INCLUDING KISN AND KMOT. NOT AS CONFIDENT AT THIS TIME WITH MVFR CEILINGS REACHING THE SOUTHERN TAF SITES. && .FIRE WEATHER... ISSUED AT 346 PM CDT WED APR 1 2015 GUSTY WESTERLY WINDS WILL CONTINUE TO BRING CRITICAL FIRE WEATHER CONDITIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA INTO THIS EVENING. WINDS WILL DIMINISH SLIGHTLY OVERNIGHT...AND WILL INCREASE AGAIN ON THURSDAY. OVER PORTIONS OF SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA THE GUSTY WINDS WILL AGAIN COMBINE WITH RELATIVE HUMIDITY VALUES AS LOW AS 30 PERCENT TO POSSIBLY BRING ANOTHER DAY OF CRITICAL FIRE WEATHER CONDITIONS. A FIRE WEATHER WATCH HAS BEEN POSTED OVER THIS AREA FOR THURSDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 10 PM CDT /9 PM MDT/ THIS EVENING FOR NDZ001>005-009>013-017>023-025-031>037-040>048-050-051. WIND ADVISORY UNTIL 8 PM CDT /7 PM MDT/ THIS EVENING FOR NDZ001>003-009>011-017>021-031>034-040>045. FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR NDZ040>046. && $$ UPDATE...TWH SHORT TERM...JJS LONG TERM...ZH AVIATION...TWH FIRE WEATHER...JJS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
910 PM EDT WED APR 1 2015 .SYNOPSIS... HIGH PRESSURE CENTERED OVER THE EASTERN GREAT LAKES WILL CONTINUE TO MOVE EAST OVERNIGHT. AN AREA OF LOW PRESSURE WILL MOVE ACROSS ONTARIO ON THURSDAY. A WARM FRONT FROM THE LOW WILL LIFT NORTH ACROSS THE AREA TOMORROW AND WILL BE FOLLOWED BY A COLD FRONT DURING THE EVENING. THE COLD FRONT WILL BECOME NEARLY STATIONARY NEAR THE OHIO RIVER FRIDAY AS LOW PRESSURE MOVES NORTHEAST ALONG THE BOUNDARY. HIGH PRESSURE WILL TRY TO BUILD OVER THE REGION FROM THE SOUTH THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... THE FIRST FEW WISPS OF CIRRUS ARE STARTING TO MAKE THEIR WAY SW INTO THE CWA. FOR THE TIME BEING THE CIRRUS WILL REMAIN SCATTERED BUT DURING THE SECOND HALF OF THE NIGHT THE CIRRUS DROPPING IN FROM THE WNW AND THE CIRRUS TO THE SW ARE EXPECTED TO MERGE OVER THE AREA. DUE TO CALLABORATION WILL ONLY ALLOW SKY COVER TO RAMP UP TO 30 TO 40% IN THE SE AND EAST. HRRR AND RUC STILL HOLDING OFF PRECIP NEARING THE WEST UNTIL AFTER 12Z SO CONTINUETO KEEP THE FORECAST DRY THE REST OF TONIGHT. LOWS WILL PROBABLY OCCUR BY 06Z THEN TEMPS MAY START TO DRIFT UP A FEW DEGREES THROUGH 12Z AS MORE HIGH CLOUDS ARRIVE AND WINDS FROM THE SOUTH START TO INCREASE. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/... THURSDAY WILL BE A WARM AND PROBABLY BUSY DAY. SHOWERS WILL SPREAD EAST ACROSS THE WESTERN END OF THE AREA DURING THE MORNING HOURS. AREAS EAST OF I-71 SHOULD REMAIN DRY THROUGH 18Z. MU CAPES GET TO AROUND 500 J/KG IN THE AFTERNOON WITH BULK SHEAR VALUES AROUND 30 KNOTS. STILL EXPECTING A LINE OF SHOWERS WITH EMBEDDED THUNDER TO DEVELOP TO THE WEST OF THE AREA DURING THE AFTERNOON AND THEN MOVE INTO NW OHIO LATE IN THE DAY. MOST AREAS WILL HEAR THUNDER FOR THE FIRST TIME THIS SPRING. WILL NEED HIGH PRECIP CHANCES ALL AREAS BY LATE IN THE DAY AND AGAIN THURSDAY NIGHT. QPF AMOUNTS IN THE HALF INCH TO THREE QUARTERS OF AN INCH RANGE ARE LIKELY. THE SURFACE COLD FRONT RESPONSIBLE FOR THIS PRECIP WILL STALL TO THE SOUTH OF THE AREA ON FRIDAY. ALL OF THE NEW GUIDANCE CONTINUES TO SHOW A WAVE DEVELOPING ALONG THE FRONT. THIS WILL PUSH THE PRECIP BACK NORTH ACROSS THE AREA LATE FRIDAY. SOUTHERN AREAS MAY NEVER GET OUT OF THE PRECIP FRIDAY BUT A DRY PERIOD IS LIKELY NEAR LAKE ERIE. MORE RAIN IS LIKELY FRIDAY NIGHT WITH THE SHOWERS QUICKLY TAPERING OFF FROM WEST TO EAST EARLY SATURDAY. HIGH PRESSURE WILL THEN START TO BUILD IN FROM THE SOUTHWEST. AS FAR AS THE SEVERE WEATHER POTENTIAL GOES FOR TOMORROW. THINK THERE COULD BE A FEW STORMS THAT APPROACH SEVERE LIMITS. HAVE SOME CONCERN THAT THERE WILL BE A LOT OF CLOUDS AROUND TOMORROW WHICH COULD LIMIT THE DESTABILIZATION. THE LATEST OUTLOOK HAS PART OF THE AREA IN THE MARGINAL CATEGORY AND THIS SEEMS REASONABLE. WILL PUT A MENTION IN THE HWO. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... SUNDAY COULD WIND UP BEING A MIXED WEATHER DEPENDING ON WHERE THE STATIONARY FRONTAL BOUNDARY LINGERS. CURRENTLY...THE FRONT IS PROGGED TO BE OVER LAKE ERIE INTO NORTHWEST PENNSYLVANIA BY SUNDAY MORNING. THE FRONT LINGERS OVER THE AREA THROUGH TUESDAY UNTIL A LOW PRESSURE SYSTEM APPROACHES FROM THE WEST. STATIONARY FRONT WILL BECOME A WARM FRONT AND LIFT NORTH OF THE AREA BY TUESDAY MORNING. THIS SHOULD KEEP THE WARM AIR ADVECTION IN THE AREA DURING THE DAY TUESDAY. THE LOW WILL MOVE EAST OF THE AREA TUESDAY NIGHT INTO WEDNESDAY DRAGGING A COLD FRONT ACROSS THE AREA. AIR MASS BEHIND THE FRONT IS NOT EXPECTED TO BE ALL THAT COLD. HIGH PRESSURE WILL QUICKLY BUILD EAST ACROSS THE NORTHERN GREAT LAKES BY THURSDAY. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE WILL SLIDE EAST OF THE AREA TONIGHT. VFR CONDITIONS WILL PREVAIL INTO THURSDAY ALTHOUGH HIGH CLOUDS WILL START TO INCREASE LATER TONIGHT. WINDS WILL BECOME SOUTH TO SOUTHEAST AND BEGIN TO INCREASE ESPECIALLY THURSDAY MORNING AS THE LOW LEVEL JET INCREASES. A WEAK WARM FRONT WILL CROSS THE AREA THURSDAY AND A FEW PASSING SHOWERS ARE LIKELY BUT THEY SHOULD BE SHORT LIVED AND CONDITIONS WILL LIKELY REMAIN VFR UNTIL MORE FREQUENT SHOWERS WITH MVFR CEILINGS AND VISIBILITY DEVELOP IN THE AFTERNOON FROM WEST TO EAST. THUNDER IS POSSIBLE BUT NOT A LOT OF CONFIDENCE ON THE TIMING AND LIKELIHOOD AT ANY GIVEN TAF SITE AND WILL LEAVE IT OUT OF THE FORECAST FOR NOW. THE COLD FRONT WILL LIKELY REACH TOLEDO BY THE END OF THURSDAY AND CEILINGS SHOULD LOWER TO IFR BEHIND THE FRONT. SOUTH WINDS WILL LIKELY GUST TO 30 KNOTS OR SLIGHTLY HIGHER ON THURSDAY. .OUTLOOK...NON-VFR INTO SATURDAY. NON VFR POSSIBLE SUNDAY MAINLY EXTREME NE OH/NW PA. && .MARINE... WINDS WILL PICK UP FROM THE SOUTH TO SOUTHWEST ACROSS THE LAKE IN THE WARM AIR ADVECTION PATTERN. AS COLD FRONT SLIPS EAST ACROSS THE LAKE THURSDAY NIGHT...WINDS DIMINISH FAIRLY QUICKLY. NORTHWEST FLOW WILL DEVELOP FRIDAY NIGHT AND THEN DIMINISH AGAIN SATURDAY AS HIGH PRESSURE BEGINS TO BUILD INTO THE REGION. GENERALLY LIGHT AND VARIABLE FLOW IS EXPECTED UNDER THE INFLUENCE OF THE HIGH AND THEN STATIONARY FRONT THROUGH MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KUBINA NEAR TERM...KUBINA/ADAMS SHORT TERM...KUBINA LONG TERM...LOMBARDY AVIATION...KOSARIK MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1037 PM EDT WED APR 1 2015 .SYNOPSIS... HIGH PRESSURE WILL MOVE EAST OF THE AREA THURSDAY AS MOIST SOUTHERLY FLOW RETURNS. A COLD FRONT WILL PUSH THROUGH NORTHEAST GEORGIA AND THE WESTERN CAROLINAS ON FRIDAY EVENING AHEAD OF DRIER HIGH PRESSURE FOR THE WEEKEND. MOISTURE WILL RETURN FOR THE START OF THE NEXT WORK WEEK AS SOUTHERLY FLOW INCREASES PRECIPITATION CHANCES. && .NEAR TERM /THROUGH THURSDAY NIGHT/... AS OF 1035 PM EDT...THE FORECAST REMAINS ON TRACK WITH THE INCOMING 00Z NAM AND THE MOST RECENT RAP RUNS DEPICTING IMPROVING MOIST UPGLIDE IN THE 3000 TO 6000 FT AGL LAYER FROM THE SW DURING THE OVERNIGHT HOURS. THIS SHOULD LEAD TO INCREASING CLOUDS...WITH MIN TEMPS SLIGHTLY WARMER THAN A CONSENSUS OF GUIDANCE. AS THE WEAK UPGLIDE AND SRLY UPSLOPE FLOW IMPROVES TOWARD DAYBREAK...ISOLD TO SCATTERED LIGHT RAIN SHOWERS SHOULD DEVELOP IN THE SRN MTNS AND IMMEDIATELY ADJACENT FOOTHILL LOCATIONS. RETURN FLOW MOISTURE WILL DEEPEN IN PROFILES THROUGH THU...GRADUALLY EXPANDING OVER MOST OF THE AREA. THE HIGHEST PRECIPITATION CHANCES WILL REMAIN FOCUSED ON THE SRLY UPSLOPE AREAS OF THE SRN MTNS AND ADJACENT FOOTHILLS...BUT WITH ISOLATED SHOWER CHANCES EVENTUALLY EXPANDING EASTWARD TO INTERSTATE 77. THE SOLIDIFYING CLOUD DECK SHOULD KEEP MAXES BELOW GUIDANCE THU AFTN...ESPECIALLY IF IN SITU SHALLOW COLD AIR DAMMING DEVELOPS EAST OF THE BLUE RIDGE. IN ADDITION TO THE MOIST UPGLIDE...A PHASING SHORTWAVE MOVING EAST FROM THE PLAINS WILL CROSS THE REGION DURING THE AFTN. HIGHER DEWPOINTS AND SLIGHTLY MORE INSTABILITY IN SRN SECTIONS MAY PERMIT ISOLD TO SCT TSTMS TO CROSS THE SRN TIER DURING THE AFTN HOURS. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 245 PM EDT WEDNESDAY...SHORT TERM BEGINS WITH SHORTWAVE PUSHING THROUGH THE SOUTHEAST AND GRADUALLY DAMPING INTO THE OVERALL LONGWAVE PATTERN. FINGER OF STABILITY ALONG THE LEE OF THE APPALACHIANS REMAINS IN PLACE AT THE BEGINNING OF THE PERIOD WITH BEST THUNDER CHANCES IN THE SOUTHERN AND SOUTHWEST PORTIONS OF THE FORECAST AREA...DIMINISHING LATE THURSDAY EVENING. NOT ENOUGH DEEP- LAYER SHEAR TO SUPPORT MUCH OF ANYTHING IN THE WAY OF ORGANIZED CONVECTION. EXPECT A BIT OF A BREAK DURING THE DAY ON FRIDAY BEHIND THE SHORTWAVE. HIGHS ON FRIDAY AFTERNOON SHOULD SOAR BACK WELL ABOVE SEASONAL NORMALS IN RESPONSE TO INCREASING LOW-LEVEL WAA AHEAD OF THE NEXT FRONT TO APPROACH FRIDAY NIGHT INTO EARLY SATURDAY. GFS AND ECMWF HAVE COME INTO MUCH BETTER AGREEMENT WITH THE PAST COUPLE OF RUNS AND BESIDES THE POTENTIAL FOR A FEW UPSLOPE SHOWERS EARLY MORNING FRIDAY...THE MAIN AREA OF PRECIPITATION SHOULD BE PUSHING INTO THE MOUNTAINS FRIDAY LATE MORNING INTO EARLY AFTERNOON. BEST AREA OF CONVECTION WILL BE MORE FRIDAY LATE EVENING AND NIGHT WHEN OF COURSE DIURNAL TRENDS WOULD MINIMIZE CAPE POTENTIAL...BUT EVEN THE MORE CONSERVATIVE GFS DOES BRING A BAND OF SBCAPE BETWEEN 100- 300 J/KG INTO THE LOWER APPALACHIANS. THE CONCERN IS THAT THIS INSTABILITY...ALBEIT WEAK...IS COLLOCATED WITH 60+KT 0-6KM SHEAR... AND 30-40KT 0-1KM SHEAR. SHERB VALUES OVERALL REMAIN BELOW 1 BUT SREF SHERB PLUME FORECASTS FOR THE AREA DO SHOW AT LEAST SOME SREF MEMBERS CREEPING ABOVE 1. SPC DAY3 OUTLOOK OVERNIGHT DID INTRODUCE MARGINAL RISK INTO THE MOUNTAINS SO CANNOT RULE OUT AN ISOLATED SEVERE STORM OR TWO AT THIS TIME...WILL HAVE TO MONITOR THE FORECAST EVOLUTION. ONLY OTHER MINOR ISSUE IS THAT DEPENDING ON TIMING OF FALLING TEMPERATURES BEHIND THE FRONT...IT IS POSSIBLE THAT SOME OF THE HIGHEST PEAKS MAY SEE A BRIEF CHANGEOVER TO SNOW EARLY SATURDAY MORNING. CONFIDENCE NOT PARTICULARLY HIGH WITH THIS AND EVEN IF IT WERE TO OCCUR NO ACCUMULATIONS WOULD BE EXPECTED. AFTER THE FRONT PUSHES THROUGH...ALL POPS MOVE OUT OF THE AREA BY 18Z SATURDAY LEAVING THE REST OF THE DAY TO BE PRETTY NICE WITH TEMPERATURES BELOW SEASONAL NORMALS. THE DRY CONDITIONS CONTINUE INTO THE EXTENDED. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 300 PM EDT WEDNESDAY...EXTENDED BEGINS WITH TEMPERATURES BELOW SEASONAL NORMALS AND CLEAR CONDITIONS BEHIND SATURDAY/S FRONT...WITH SURFACE HIGH PRESSURE IN PLACE AND WEAK NORTHWEST FLOW ALOFT... LEADING TO A NICE EASTER SUNDAY. PRECIPITATION SPREADS ACROSS THE MIDSOUTH AND DEEP SOUTH LATE SUNDAY INTO EARLY MONDAY IN RESPONSE TO A WEAK SHORTWAVE AND ISENTROPIC LIFT ON THE WESTERN PERIPHERY OF THE SURFACE HIGH THAT BY THIS POINT HAS PUSHED OFF INTO THE ATLANTIC. STILL SOME QUESTION ABOUT QPF VALUES AS WELL AS HOW WIDESPREAD THE PRECIPITATION WILL BE...WITH GFS A LITTLE MORE ROBUST ON MONDAY THAN THE ECMWF...AND HAVE CONTINUED TREND OF GENERALLY LOW CHANCE POPS ESPECIALLY WEST DURING THE DAY ON MONDAY. LATE IN THE PERIOD...ANOTHER DEEP TROUGH IN THE ROCKIES PUSHES INTO THE PLAINS. WEAK RIDGING ALOFT OVER THE GULF COMBINED WITH THE DEEPENING TROUGH WILL PRODUCE SOUTHWEST FLOW ALOFT ACROSS THE SOUTHEAST BUT AGAIN SIGNIFICANT UNCERTAINTY REMAINS IN EXACTLY WHERE THE SUBTROPICAL JET MIGHT SET UP. GFS WANTS TO KEEP A BAND OF PRECIPITATION ACROSS THE SOUTHEAST WITH THE ASSOCIATED FRONT PUSHING INTO THE MID-ATLANTIC REGION TUESDAY EVENING WHEREAS THE ECMWF HAS THE MOIST FETCH A BIT FARTHER NORTH MORE IN THE OHIO VALLEY...WITH THE FRONT LINGERING ACROSS THE UPPER MIDWEST. WITH THESE DIFFERENCES AND RESULTING FAIRLY LOW CONFIDENCE...HAVE KEPT TREND OF SLIGHT TO LOW CHANCE POPS WITH A BIT OF A DIURNAL TREND IN THUNDER POTENTIAL. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... AT KCLT...MOISTURE WILL RETURN AT VFR LEVELS OVERNIGHT...WITH A STRATOCUMULUS CIG LIKELY BY MID MORNING ON THURSDAY. DEEPENING MOIST UPGLIDE WILL ALLOW CIGS TO LOWER INTO THE MVFR RANGE THROUGH THE AFTN HOURS. SPOTTY LIGHT SHOWERS CANNOT BE RULED OUT...BUT CHANCES LOOK TOO LOW TO MENTION IN THE TAF AT PRESENT. LIGHT ESE FLOW WILL GRADUALLY BECOME MORE SRLY WITH TIME THROUGH THE TAF PERIOD. ELSEWHERE...VFR LEVEL STRATOCUMULUS WILL DEVELOP FROM S TO N ACROSS THE MTN AND FOOTHILL TAFS TONIGHT. MVFR CIGS WILL THEN BECOME INCREASINGLY LIKELY THROUGH THU MORNING AT KAVL AND THE SC SITES AS THE MOIST UPGLIDE DEEPENS. THERE IS GENERAL CONSENSUS AMONG THE MODELS/MOS ON IFR CIGS FROM KAVL TO KGSP AND POINTS S BY EARLY AFTN...BUT THE IFR CIGS COULD BE TEMPO MVFR ALL AFTN. WILL MENTION VCSH WITH THE DEEPEST MOISTURE THROUGHOUT...AND LIMIT PROB30 FOR TSRA TO KAND WITH THE UPPER SHORTWAVE INTERACTING WITH MORE UNSTABLE AIR ACROSS THE SRN PART OF THE TERMINAL AREA LATE DAY. EXPECT EASTERLY WINDS TO TOGGLE SOUTHERLY OVER TIME...BUT PERHAPS ADJUST BACK TO EASTERLY IN ANY WEAK CAD REGIONS FROM KGMU TO KHKY. OUTLOOK...MOIST SOUTHEAST UPSLOPE FLOW WILL CONTINUE THURSDAY NIGHT INTO FRIDAY MORNING WHICH WILL PROMOTE MVFR TO IFR CEILINGS. CONDITIONS WILL IMPROVE TO VFR BY FRIDAY AFTERNOON. A COLD FRONT WILL AFFECT THE AREA FRIDAY NIGHT INTO EARLY SATURDAY...BRINGING ANOTHER ROUND OF RAIN/POSSIBLE THUNDERSTORMS AND RESTRICTIONS. VFR WILL RETURN FOR THE REST OF THE WEEKEND. CONFIDENCE TABLE... 02-08Z 08-14Z 14-20Z 20-00Z KCLT HIGH 100% HIGH 100% HIGH 100% MED 77% KGSP HIGH 100% HIGH 95% HIGH 89% MED 73% KAVL HIGH 100% HIGH 82% HIGH 84% HIGH 93% KHKY HIGH 100% HIGH 100% HIGH 98% HIGH 91% KGMU HIGH 100% HIGH 91% MED 61% MED 68% KAND HIGH 100% HIGH 87% MED 69% HIGH 81% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...RWH NEAR TERM...HG SHORT TERM...TDP LONG TERM...TDP AVIATION...HG
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
645 PM CDT WED APR 1 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 405 PM CDT WED APR 1 2015 THE MAIN WEATHER FOCUS FOR TONIGHT WILL BE THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT ALONG AN ADVANCING COLD FRONT. WHILE THE FRONTAL PROGRESSION HAS SLOWED SOME...MOISTURE RETURNS HAVE ALSO BEEN SLOW. DEWPOINTS ARE JUST STARTING TO BUILD INTO THE LOW TO MID 40S...WITH THE 50+ READINGS STILL WELL SOUTH OF THE REGION. AS A RESULT...CAPE VALUES REMAIN FAIRLY MINIMAL...HOWEVER MID LEVEL LAPSE RATES ARE EXPECTED TO INCREASE THROUGH THIS AFTERNOON. SOUNDINGS SHOW A STRONG INVERTED V WITH A LONG AND SKINNY CAPE AND UNIDIRECTIONAL SHEAR. STILL EXPECT THUNDERSTORMS TO DEVELOP ALONG THE FRONT...HOWEVER THE TIMING OF INITIATION IS A BIT LATER THAT PREVIOUS MODEL RUNS. THE BEST WINDOW OF OPPORTUNITY WOULD BE IN THE EARLY EVENING...WITH STORMS QUICKLY DEVELOPING INTO A LINEAR STRUCTURE. THESE STORMS WILL PROGRESS EAST WITH THE FRONT FAIRLY QUICKLY BEFORE EXITING THE FORECAST AREA BY MIDNIGHT. SEVERE STORMS STILL LOOK POSSIBLE...BUT THE MAIN THREAT WILL PRIMARILY BE DAMAGING WINDS. WITH SURFACE WINDS ALREADY AVERAGING 25 TO 35 MPH...IT WILL NOT TAKE MUCH TO GET SEVERE WIND GUSTS TO OCCUR GIVEN THE INVERTED V SOUNDINGS. THE MAIN SEVERE THREAT WILL BE DAMAGING GUSTS TO 65 OR 70 MPH. HAIL SEEMS LIKE MUCH LESS OF A THREAT AND WOULD BE LARGELY SUB SEVERE. FOLLOWED A BLEND OF THE HRRR AND RAP...WHICH HAVE CONSISTENTLY BEEN SHOWING STORMS DEVELOPING ALONG A LINE FROM NEAR SIOUX CITY TO ORANGE CITY TO WINDOM AROUND 6 OR 7 PM AND TRACKING EAST INTO THE EVENING. STILL LOOKS LIKE STORM DEVELOPMENT WILL FIRE JUST OUTSIDE OF THE SIOUX FALLS AREA...SO HAVE KEPT POPS AROUND 20 PERCENT. ALSO LOWERED QPF AMOUNTS QUITE A BIT GIVEN THE DRIER SCENARIO...BUT COULD SEE LOCALLY AROUND A HALF INCH OF RAIN UNDER A THUNDERSTORM. STRONG WINDS AHEAD OF THE FRONT WILL DECREASE A LITTLE AS THE FRONT ARRIVES THEN TURN NORTHWEST AROUND 20 TO 30 MPH. DECIDED TO EXTEND THE WIND ADVISORY A FEW MORE HOURS THIS AFTERNOON BUT SHOULD BE GOOD TO EXPIRE AROUND 6 PM. AS THE EVENING PROGRESSES WINDS WILL BE ON AN OVERALL DOWNWARD TREND. AFTER MIDNIGHT WINDS WILL SETTLE CLOSER TO 5 TO 10 MPH. LOWS TONIGHT WILL RANGE FROM THE UPPER 30S IN THE WEST TO UPPER 40S IN THE SOUTHEAST. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 405 PM CDT WED APR 1 2015 COOLER AND BREEZY ON THURSDAY...WITH HIGHS IN THE 50S AND 60S AND WEST NORTHWEST WINDS INCREASING INTO THE 20 TO 35 MPH RANGE BY AFTERNOON. GIVEN EXPECTED DEEP MIXING DEWPOINTS WILL LIKELY BE LOWER THAN MOST GUIDANCE. THIS IMPACTS FIRE WEATHER AND IS DESCRIBED BELOW. STILL LOOKS LIKE ANY PRECIPITATION FROM THE WAVE CROSSING THE PLAINS WILL STAY TO OUR SOUTH THURSDAY NIGHT...ALTHOUGH WILL LIKELY SEE INCREASING MID AND HIGH CLOUDS BY THURSDAY AFTERNOON. COOLER AIR ADVECTS IN THURSDAY NIGHT INTO FRIDAY...RESULTING IN MORNING LOWS IN THE 20S AND 30S AND DAYTIME HIGHS ONLY IN THE 40S AND 50S. WILL BE A SUNNY DAY AND WINDS WILL BE A BIT LIGHTER THOUGH...MORE IN THE 10 TO 20 MPH RANGE. A BIT OF A TRICKY FORECAST FOR THE WEEKEND WITH REGARDS TO TEMPERATURES. SHOULD REMAIN DRY...BUT WILL LIKELY SEE A DECENT GRADIENT IN TEMPERATURES WITH A BOUNDARY NEARBY. LATEST MODEL TRENDS SUGGEST A SLIGHTLY FURTHER NORTH POSITION OF THE BOUNDARY...ALLOWING FOR WARMER TEMPERATURES IN OUR REGION. SO TRENDED HIGHS IN THAT DIRECTION...WITH MOST LOCATIONS IN THE 50S AND 60S...POSSIBLY SOME LOW 70S ALONG THE MISSOURI RIVER. FORECAST UNCERTAINTY CONTINUES INTO NEXT WEEK AS MODELS STRUGGLE WITH MAGNITUDE AND TIMING OF WAVES EJECTING EAST OUT OF THE LONGWAVE WEST COAST TROUGH. AS OF NOW LOOKS LIKE A SLIGHT CHANCE OF AN ELEVATED SHOWER OR THUNDERSTORM SUNDAY NIGHT ALONG THE ELEVATED WARM FRONT. AS LOW LEVEL MOISTURE INCREASES...COULD ALSO SEE SOME STRATUS AND DRIZZLE. QUESTION THEN BECOMES WHERE THE LOW TRACKS AND HOW FAST IT MOVES EAST. GEM AND GFS ARE IN ONE CAMP MOVING THE SURFACE LOW OVERHEAD MONDAY AND EXITING TO THE EAST MONDAY NIGHT...WITH THE ECMWF KEEPING MORE OF THE ENERGY BACK AND MOVING THE LOW BY ON TUESDAY. SO FOR NOW CAN JUST SAY PRECIPITATION CHANCES INCREASE MONDAY INTO TUESDAY...BUT EXACT TIMING IS UNCERTAIN. TRACK OF THE LOW WILL DETERMINE WHETHER WE SEE A COLD RAIN OR SOME THUNDERSTORMS. CURRENT CONSENSUS LEANS TOWARDS A COOLER RAIN...WITH MAYBE A FEW STORMS ALONG THE MISSOURI RIVER. BUT THIS COULD CHANGE DEPENDING ON THE EXACT TRACK...AND CAN NOT EVEN RULE OUT SOME SNOW MIXING IN...SO WILL NEED TO MONITOR TRENDS. ANOTHER WAVE MAY BRING ANOTHER PRECIPITATION THREAT WEDNESDAY INTO THURSDAY...SO MAIN STORY WILL BE THE MORE ACTIVE PRECIPITATION THREAT NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 642 PM CDT WED APR 1 2015 THUNDERSTORMS CONTINUE TO FORM JUST EAST OF FSD THIS EVENING ALONG AN ADVANCING LOW LVL FRONT. THIS ACTIVITY IS EXPECTED TO REMAIN EAST OF FSD. AT KSUX...PERIODS OF THUNDERSTORM ARE EXPECTED FOR THE NEXT 1 TO 2 HOURS. WILL BE MONITORING CONVECTION FURTHER SOUTHWEST ALONG THE FRONT IN NEBRASKA. THIS CONVECTION COULD BECOME BETTER ORGANIZED AND CLIP THE AIRPORT WITHIN A THE STRATIFORM REGION AFTER 02Z. OTHERWISE...ONCE CONVECTION MOVES EAST NORTHWEST WINDS WILL PREVAIL OVERNIGHT WITH ANOTHER GUSTY...BUT VFR...DAY EXPECTED ON THURSDAY. && .FIRE WEATHER... ISSUED AT 405 PM CDT WED APR 1 2015 RED FLAG WARNING WILL CONTINUE INTO EARLY THIS EVENING...WITH STRONG SOUTHWESTERLY WINDS AHEAD OF THE FRONT TURNING NORTHWESTERLY BEHIND IT. UPGRADED SOUTHEAST SOUTH DAKOTA AND SOUTHWEST MINNESOTA TO A RED FLAG WARNING FOR THURSDAY. DEEP MIXING WILL ALLOW FOR RH VALUES TO DROP INTO THE 15 TO 25 PERCENT RANGE FROM LATE MORNING THROUGH THE AFTERNOON. NORTHWESTERLY WINDS WILL ALSO INCREASE INTO THE 20 TO 35 MPH RANGE. KEPT NORTHEAST NEBRASKA AND NORTHWEST IOWA OUT FOR NOW. WINDS ARE MORE BORDERLINE THERE...15 TO 30 MPH AND RAINFALL THIS AFTERNOON AND EVENING MAY BE ENOUGH TO LIMIT FIRE THREAT. HOWEVER IF RAIN TONIGHT ENDS UP MORE SCATTERED OR LESS THAN EXPECTED...MIDNIGHT SHIFT WILL NEED TO CONSIDER INCLUDING THEM IN THE RED FLAG WARNING AS WELL. THE LOW RH CONTINUES FRIDAY INTO SATURDAY...15 TO 25 PERCENT...BUT WINDS SHOULD BE LIGHTER. GENERALLY 10 TO 25 MPH ON FRIDAY OUT OF THE NORTHWEST AND 10 TO 20 MPH OUT OF THE SOUTH ON SATURDAY. THIS SHOULD KEEP US BELOW RED FLAG CRITERIA BOTH DAYS...BUT STILL EXPECT HIGH TO VERY HIGH FIRE DANGER GIVEN DRY FUELS AND LOW RH. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR SDZ255>258. RED FLAG WARNING FROM 11 AM TO 7 PM CDT THURSDAY FOR SDZ255>258. MN...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR MNZ900. RED FLAG WARNING FROM 11 AM TO 7 PM CDT THURSDAY FOR MNZ900. IA...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR IAZ300-301. NE...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ249. && $$ SHORT TERM... LONG TERM...CHENARD AVIATION...DUX FIRE WEATHER...CHENARD
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Area Forecast Discussion National Weather Service Spokane WA 259 AM PDT WED APR 1 2015 .SYNOPSIS... A cool and showery spring weather pattern will continue through the week and into the weekend. Nighttime freezing temperatures will be common over the next 7 days with daytime temperatures in the 50s. && .DISCUSSION... Today and tonight: A trough of cold air is squarely over the Pac NW today. This creates a very unstable atmosphere with steep lapse rates. Surface afternoon heating is all we`ll need to realize this instability into showers. The limiting factor will be moisture; there`s not a lot of it. Surface dew points are generally in the 20s. Showers will develop by midday and gradually die off after sunset. The northeast mountains and the central Panhandle will be favored in this pattern, with the lowest chance of showers in the Columbia Basin. The northwest flow means that showers that develop over the Selkirks could move into the Spokane/CdA metro area in the late afternoon. The cold dry air means that some of the precipitation could be in the form of snow or graupel. This also isn`t good for the thunderstorm potential, as Lifted Condensation Levels (LCLs) will have temperatures of -5C or colder, which is often too cold for much lightning. Freezing temperatures are expected in many areas tonight. Much of our area still hasn`t started its growing season. But the Moses Lake area has, so a Freeze Warning will be issued for there. Lewiston and Wenatchee will likely be in the mid 30s tonight. Thursday and Thursday Night: The cold air aloft moves to the east into Montana. As such, the atmosphere in the Inland Northwest will stablize somewhat. So shower activity should be less on Thursday. The favored location for showers will be in the Panhandle mountains. RJ Friday through Saturday night: A cold upper level low pressure system will dig off of the west coast. Models are in good agreement that a shortwave swinging around this upper level low will push across a cold front around the Friday afternoon into Friday night time frame. The upper level dynamics with this system looks to weaken as it pushes further inland away from its parent upper low. This should translate into more of a weak to moderately strong cold front passage. Best forcing would be across the northern portion of the forecast area where precip chances will be highest. Precip type is expected to be in the form of valley rain and mountain snow showers. Snow levels will drop behind the front with diurnally driven rain/graupel showers possible for the afternoon on Saturday. ...VALLEY SNOW POSSIBLE IN THE PANHANDLE SUNDAY NIGHT... Sunday through Wednesday: The cold upper level trough of low pressure in the eastern Pacific will dig further down the coast through the weekend. A second shortwave disturbance will rotate around the upper trough and push across OR, the ID Panhandle and into western MT. There is general agreement amongst the mid range model guidance that this piece of energy will maintain its strength as it moves inland. The second piece of energy will be working with stronger jet dynamics that will help to fuel cyclogenesis at lower levels in the atmosphere. The track of the surface low and its intensity is still a matter of great uncertainty at this time. The ECMWF and Canadian solutions show more of a westerly track to the surface low across the ID Panhandle. This would lend to a better chance for drawing down colder air from the north with a deformation band developing across western MT and across the ID Panhandle. If this solution verifies, then there is a chance for snow down to valley floors. A couple of inches of snow or more in the valleys would not be out of the question; However, there is too much uncertainty amongst the model guidance to put much confidence in this scenario, but it will be a situation worth monitoring as the weekend approaches. The upper level low in the eastern Pacific is progged to open up and push into the western U.S. for early next week with the weather over the Inland Northwest remaining unsettled. Showers are more likely to be diurnal in nature. Temperatures are expected to be below normal through the weekend into early next week. /SVH && .AVIATION... 06Z TAFS: A cold upper level trof will remain over the region into Wednesday. The atmosphere will destabilize Wednesday afternoon promoting scattered showers and possibly a few thunderstorms especially over northeast Washington and the Idaho Panhandle. Several type of precipitation are possible with these showers...including rain...snow...small hail...and graupel. Gusty outflow winds will also be possible. Given that there is only a slight chance of thunderstorms left mention out of all TAF sites. Thermal temperature profiles suggest the Idaho Panhandle having the best opportunity for isolated thunderstorms. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 50 30 53 33 54 29 / 50 30 10 10 10 30 Coeur d`Alene 49 28 52 30 54 27 / 70 40 30 20 20 40 Pullman 48 31 49 33 54 33 / 50 30 20 10 10 30 Lewiston 53 33 54 33 59 34 / 40 20 20 10 10 40 Colville 53 30 57 32 55 28 / 60 30 20 10 20 40 Sandpoint 50 28 52 28 52 28 / 70 40 30 30 20 50 Kellogg 44 29 47 31 50 30 / 70 60 30 40 20 40 Moses Lake 58 30 59 33 59 31 / 20 0 0 0 10 20 Wenatchee 58 37 60 38 58 33 / 20 0 0 10 20 40 Omak 57 32 60 33 58 28 / 40 10 10 10 30 40 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...Freeze Warning from 3 AM to 9 AM PDT Thursday for Moses Lake Area. && $$
Area Forecast Discussion National Weather Service Spokane WA 259 AM PDT WED APR 1 2015 .SYNOPSIS... A cool and showery spring weather pattern will continue through the week and into the weekend. Nighttime freezing temperatures will be common over the next 7 days with daytime temperatures in the 50s. && .DISCUSSION... Today and tonight: A trough of cold air is squarely over the Pac NW today. This creates a very unstable atmosphere with steep lapse rates. Surface afternoon heating is all we`ll need to realize this instability into showers. The limiting factor will be moisture; there`s not a lot of it. Surface dew points are generally in the 20s. Showers will develop by midday and gradually die off after sunset. The northeast mountains and the central Panhandle will be favored in this pattern, with the lowest chance of showers in the Columbia Basin. The northwest flow means that showers that develop over the Selkirks could move into the Spokane/CdA metro area in the late afternoon. The cold dry air means that some of the precipitation could be in the form of snow or graupel. This also isn`t good for the thunderstorm potential, as Lifted Condensation Levels (LCLs) will have temperatures of -5C or colder, which is often too cold for much lightning. Freezing temperatures are expected in many areas tonight. Much of our area still hasn`t started its growing season. But the Moses Lake area has, so a Freeze Warning will be issued for there. Lewiston and Wenatchee will likely be in the mid 30s tonight. Thursday and Thursday Night: The cold air aloft moves to the east into Montana. As such, the atmosphere in the Inland Northwest will stablize somewhat. So shower activity should be less on Thursday. The favored location for showers will be in the Panhandle mountains. RJ Friday through Saturday night: A cold upper level low pressure system will dig off of the west coast. Models are in good agreement that a shortwave swinging around this upper level low will push across a cold front around the Friday afternoon into Friday night time frame. The upper level dynamics with this system looks to weaken as it pushes further inland away from its parent upper low. This should translate into more of a weak to moderately strong cold front passage. Best forcing would be across the northern portion of the forecast area where precip chances will be highest. Precip type is expected to be in the form of valley rain and mountain snow showers. Snow levels will drop behind the front with diurnally driven rain/graupel showers possible for the afternoon on Saturday. ...VALLEY SNOW POSSIBLE IN THE PANHANDLE SUNDAY NIGHT... Sunday through Wednesday: The cold upper level trough of low pressure in the eastern Pacific will dig further down the coast through the weekend. A second shortwave disturbance will rotate around the upper trough and push across OR, the ID Panhandle and into western MT. There is general agreement amongst the mid range model guidance that this piece of energy will maintain its strength as it moves inland. The second piece of energy will be working with stronger jet dynamics that will help to fuel cyclogenesis at lower levels in the atmosphere. The track of the surface low and its intensity is still a matter of great uncertainty at this time. The ECMWF and Canadian solutions show more of a westerly track to the surface low across the ID Panhandle. This would lend to a better chance for drawing down colder air from the north with a deformation band developing across western MT and across the ID Panhandle. If this solution verifies, then there is a chance for snow down to valley floors. A couple of inches of snow or more in the valleys would not be out of the question; However, there is too much uncertainty amongst the model guidance to put much confidence in this scenario, but it will be a situation worth monitoring as the weekend approaches. The upper level low in the eastern Pacific is progged to open up and push into the western U.S. for early next week with the weather over the Inland Northwest remaining unsettled. Showers are more likely to be diurnal in nature. Temperatures are expected to be below normal through the weekend into early next week. /SVH && .AVIATION... 06Z TAFS: A cold upper level trof will remain over the region into Wednesday. The atmosphere will destabilize Wednesday afternoon promoting scattered showers and possibly a few thunderstorms especially over northeast Washington and the Idaho Panhandle. Several type of precipitation are possible with these showers...including rain...snow...small hail...and graupel. Gusty outflow winds will also be possible. Given that there is only a slight chance of thunderstorms left mention out of all TAF sites. Thermal temperature profiles suggest the Idaho Panhandle having the best opportunity for isolated thunderstorms. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 50 30 53 33 54 29 / 50 30 10 10 10 30 Coeur d`Alene 49 28 52 30 54 27 / 70 40 30 20 20 40 Pullman 48 31 49 33 54 33 / 50 30 20 10 10 30 Lewiston 53 33 54 33 59 34 / 40 20 20 10 10 40 Colville 53 30 57 32 55 28 / 60 30 20 10 20 40 Sandpoint 50 28 52 28 52 28 / 70 40 30 30 20 50 Kellogg 44 29 47 31 50 30 / 70 60 30 40 20 40 Moses Lake 58 30 59 33 59 31 / 20 0 0 0 10 20 Wenatchee 58 37 60 38 58 33 / 20 0 0 10 20 40 Omak 57 32 60 33 58 28 / 40 10 10 10 30 40 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...Freeze Warning from 3 AM to 9 AM PDT Thursday for Moses Lake Area. && $$
Area Forecast Discussion National Weather Service Spokane WA 1031 PM PDT TUE MAR 31 2015 .SYNOPSIS... An unsettled and ocassionally showery spring-like weather pattern will continue through the week and into the weekend. Widespread freezing temperatures are possible Thursday and Friday morning. Then anticipate more seasonal temperatures by early next week. && .DISCUSSION... Update: The cold front responsible for the windy conditions over much of Central and Eastern Washington today has shifted east of the area with cooler and drier air moving in behind the front. Dew points have fallen into the upper teens and 20s in many areas due to the drier air. Radar this evening showed a few areas of showers that linger. A cold pool aloft with 500mb temps down to -33C combined with low level upslope flow is resulting in showers across southeast Washington extending into the Central Panhandle Mountains mainly over the high terrain. Showers also linger near the Cascade crest with a Puget Sound Convergence Zone resulting in a band of moderate snow between Stevens Pass and Snoqualmie Pass. Radar trends as well as the HRRR suggest the heaviest snow tonight should stay south of Stevens Pass although some travel impacts are still possible between Stevens Pass and Leavenworth. Outside of these areas most of the Inland Northwest is expected to remain dry tonight. Pressure gradients will also be decreasing tonight which combined with less mixing potential with the loss of daytime heating will lead to decreasing winds through the night. However very few changes were made to the forecast tonight. Main update was to make slight changes to winds this evening based on latest observations. JW && .AVIATION... 06Z TAFS: A cold upper level trof will remain over the region into Wednesday. The atmosphere will destabilize Wednesday afternoon promoting scattered showers and possibly a few thunderstorms especially over northeast Washington and the Idaho Panhandle. Several type of precipitation are possible with these showers...including rain...snow...small hail...and graupel. Gusty outflow winds will also be possible. Given that there is only a slight chance of thunderstorms left mention out of all TAF sites. Thermal temperature profiles suggest the Idaho Panhandle having the best opportunity for isolated thunderstorms. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 33 51 29 52 31 54 / 10 50 20 20 20 20 Coeur d`Alene 31 51 28 50 30 54 / 10 60 30 30 30 20 Pullman 34 49 30 49 32 54 / 20 40 30 20 10 10 Lewiston 37 55 33 54 34 59 / 30 40 20 20 10 10 Colville 33 55 29 55 31 55 / 10 40 20 20 10 30 Sandpoint 31 51 27 50 28 52 / 20 60 20 40 30 40 Kellogg 31 45 29 45 31 50 / 20 60 50 50 30 20 Moses Lake 37 60 30 59 31 59 / 10 20 0 0 10 10 Wenatchee 38 58 34 59 37 58 / 10 20 0 10 10 20 Omak 32 57 30 59 32 58 / 10 30 10 10 10 30 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
615 AM CDT TUE MAR 31 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 311 AM CDT TUE MAR 31 2015 AFTER DENSE FOG THIS MORNING ACROSS PORTIONS OF SOUTHWEST INTO CENTRAL WISCONSIN...MAIN FORECAST CONCERN IS ON SHOWER AND THUNDERSTORM CHANCES LATE WEDNESDAY AFTERNOON THROUGH EARLY THURSDAY MORNING. KEEPING A CLOSE EYE ON DENSE FOG DEVELOPING ACROSS PORTIONS OF SOUTHWEST INTO CENTRAL WISCONSIN...PARTICULARLY FOR THOSE AREAS THAT RECEIVED RAINFALL YESTERDAY WHICH HELPED BOOST AVAILABLE LOW LEVEL MOISTURE FOR FOG FORMATION. HAVE ISSUED A DENSE FOG ADVISORY THROUGH 10 AM FOR THESE AREAS WITH VISIBILITIES EXPECTED TO FALL TO 1/4 MILE OR LESS AT TIMES. WHERE TEMPERATURES ARE BELOW FREEZING THE FOG MAY FREEZE TO SOME ROAD SURFACES CREATING SLIPPERY TRAVEL CONDITIONS. AFTER THE EARLY MORNING FOG...WILL BE WATCHING LOW PRESSURE DROPPING SOUTHEAST OUT OF SOUTHWEST ONTARIO...ACROSS LAKE SUPERIOR AND INTO EASTERN WISCONSIN BY LATE THIS AFTERNOON INTO EARLY THIS EVENING. PRECIPITATION WITH THIS FEATURE SHOULD STAY WELL NORTHEAST OF THE FORECAST AREA. WE SHOULD SEE GOOD MIXING TODAY WITH A DROP IN DEW POINTS THIS AFTERNOON AND AN INCREASE IN WINDS AS WE MIX OUT TO 4000 TO 5000 FT. WE SHOULD SEE AFTERNOON RELATIVE HUMIDITY VALUES DROP INTO THE MID TO LOWER 30S ACROSS CENTRAL WISCONSIN AS THIS DEEPER MIXING OCCURS. ALSO...WINDS WILL INCREASE TO 13 TO 15 MPH WITH GUSTS IN THE 20 TO 25 MPH HOUR RANGE. WEAK HIGH PRESSURE SLIDES EAST OF THE REGION TONIGHT AS THE PRESSURE GRADIENT STARTS TO INCREASE WEST OF THE MISSISSIPPI RIVER AS A TROUGH APPROACHES FROM THE NORTHERN ROCKIES. THE TROUGH WILL HELP DRIVE A COLD FRONT SOUTHEAST INTO THE REGION ON WEDNESDAY. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 311 AM CDT TUE MAR 31 2015 GULF MOISTURE WILL STREAM NORTHWARD AHEAD OF THE FRONT BRINGING DEW POINT VALUES INTO THE MID 50S JUST AHEAD OF THE FRONT ACROSS PORTIONS OF SOUTHERN MINNESOTA AND NORTHERN IOWA BY LATE WEDNESDAY AFTERNOON. THESE HIGHER DEW POINTS WONT MAKE INTO THE FORECAST AREA UNTIL LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING SO EXPECTING DEW POINTS TO MIX OUT INTO THE 30S BY EARLY WEDNESDAY AFTERNOON. ALSO...WITH THE LATER ARRIVAL OF THE FRONT WE SHOULD SEE TEMPERATURES WARM WELL INTO THE UPPER 60S TO LOWER 70S. THESE WARM TEMPERATURES...LOWER DEW POINTS...AND BREEZY SOUTH WINDS OF 15 TO 24 MPH COULD CREATE SOME FIRE WEATHER CONCERNS. WILL HAVE TO KEEP A VERY CLOSE EYE ON MOISTURE RETURN WEDNESDAY AFTERNOON. HAVE INCREASES HIGH TEMPERATURES A FEW DEGREE AND DROPPED DEW POINTS. LOOK FOR MINIMUM RELATIVE HUMIDITY VALUES TO FALL INTO THE LOWER 30S AND POSSIBLY THE UPPER 20S IF DEEPER MIXING OCCURS. MOISTURE WILL RAPIDLY INCREASE LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING AS THE COLD FRONT ADVANCES EASTWARD. 0-1 KM MUCAPE VALUES CLIMB TO 500 TO 1000 J/KG NEAR AND JUST WEST OF THE I- 35 CORRIDOR LATE WEDNESDAY AFTERNOON. THESE CAPE VALUES COMBINED WITH 0-6 KM BULK SHEAR VALUES OF 30 TO 40 KTS SUGGEST THE POTENTIAL FOR A FEW STRONG TO SEVERE STORMS ALONG THE FRONT. CAPE REALLY WANES IN THE EVENING AS THE FRONT PUSHES INTO SOUTHEAST MINNESOTA AND NORTHEAST IOWA SO STORM SHOULD GENERALLY BE ON A WEAKENING TREND AS THEY MOVE IN. SHOWERS AND STORMS WILL SPREAD ACROSS THE AREA WEDNESDAY NIGHT AND CONTINUE INTO THE OVERNIGHT HOURS BEFORE EXITING THURSDAY MORNING. NOT EXPECTING SEVERE WEATHER AT THIS TIME BUT WILL HAVE TO KEEP A CLOSE EYE ON THE STORMS THAT FIRE NEAR AND WEST OF THE I-35 CORRIDOR TO SEE IF THEY CAN HOLD TOGETHER AS THEY PUSH EAST INTO THE FORECAST AREA. THE ENTIRE FORECAST AREA WILL LIKELY SEE RAIN OUT OF THIS SYSTEM WIT LOCATIONS ACROSS NORTHEAST IOWA INTO FAR SOUTHWEST WISCONSIN SEEING THE MOST. RAINFALL AMOUNTS COULD APPROACH AN INCH ACROSS THESE AREAS. THE FRONT FINALLY EXITS THE REGION BY LATE THURSDAY MORNING TAKING ANY LINGERING SHOWERS WITH IT. COOLER AIR RETURNS ON FRIDAY AS 850 MB TEMPS FALL TO -4 TO -7 C. PLAN ON HIGHS ON FRIDAY RANGING FROM THE LOWER 40S OVER NORTH CENTRAL WISCONSIN TO THE MID TO UPPER 40S ELSEWHERE. FLOW THEN TRANSITIONS TO ZONAL FLOW FOR THE WEEKEND INTO EARLY NEXT WEEK AND WE HANG RIGHT IN THE BAROCLINIC ZONE. A FEW WEAK SHORTWAVES MOVE THROUGH THE REGION SATURDAY INTO SUNDAY POSSIBLY GENERATING LIGHT RAIN OR SNOW...DEPENDING ON THE TIMING OF THE WEAK SYSTEMS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 615 AM CDT TUE MAR 31 2015 FOG DEVELOPED OVERNIGHT ACROSS THE AREAS THAT RECEIVED THE LIGHT RAIN MONDAY. THIS FOG HAS CREPT INTO KLSE AND WAS PRODUCING IFR CONDITIONS. THE FOG MAY ALSO GET INTO KRST FOR A SHORT PERIOD AND PRODUCE SOME MVFR CONDITIONS. LOOKING AT THE 31.09Z RAP BUFKIT SOUNDINGS...EXPECTING THIS FOG TO LIFT BY THE MIDDLE OF THE MORNING. ONCE THE FOG IS GONE...VFR CONDITIONS EXPECTED FOR THE REMAINDER OF THE PERIOD WITH THE REGION IN BETWEEN AREAS OF LOW PRESSURE. THERE COULD BE A PERIOD OF SOME GUSTY WINDS THIS AFTERNOON AS DECENT LAPSE RATES DEVELOP IN THE MIXED LAYER. THE 31.06Z NAM BUFKIT SOUNDING SUGGEST THESE GUSTS SHOULD BE AROUND 20 KNOTS FOR BOTH AIRPORTS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR WIZ017-029- 032>034-042>044. MN...NONE. IA...NONE. && $$ SHORT TERM...WETENKAMP LONG TERM...WETENKAMP AVIATION...04
AREA FORECAST DISCUSSION
NWS RENO NV
945 PM PDT WED APR 1 2015 .UPDATE... WIDESPREAD AREA OF SHOWERS HAS DEVELOPED THIS EVENING FROM HWY 50 NORTH TO NEAR SUSANVILLE. THIS IS ASSOCIATED WITH APPROACHING UPPER TROUGH AND WAS NOTED WELL BY EARLIER HRRR AND NAM RUNS. FAIRLY DRY LOW LEVELS HAVE LIMITED PRECIP AMOUNTS THUS FAR THOUGH THERE HAS BEEN SOME REPORTS OF RAIN/SNOW MIX DOWN TO ~5000 FT. GUIDANCE THROUGH THE OVERNIGHT HOURS SUGGESTS A GRADUAL WANE OF THE SHOWER COVERAGE PAST MIDNIGHT BUT HAVE CONTINUED SCATTERED-ISOLATED COVERAGE BASED ON RADAR TRENDS. AS TEMPS COOL, COULD SEE SOME LIGHT ACCUMULATIONS OF SNOW ABOVE 5000 FT ON BRIDGES AND NON-PAVED SURFACES. SOMETHING TO WATCH. OTHERWISE NO MAJOR CHANGES TO THE FORECAST. CS && .SYNOPSIS... MUCH COLDER TEMPERATURES WILL CONTINUE INTO THURSDAY, WITH A FEW LIGHT SNOW AND RAIN SHOWERS THIS EVENING MAINLY NORTH OF HIGHWAY 50. COLD TEMPERATURES ARE EXPECTED FRIDAY MORNING WITH WARMER DAYS EXPECTED FRIDAY INTO SATURDAY. COLD AND BREEZY CONDITIONS RETURN LATER IN THE WEEKEND AND EARLY NEXT WEEK, WITH AN INCREASING CHANCE FOR PRECIPITATION. && .SHORT TERM... NOT MANY CHANGES MADE TO THE SHORT TERM WITH THE INITIAL FEATURE OF INTEREST A SHORT WAVE MOVING INTO OREGON THIS AFTERNOON. IT WILL MOVE SOUTHEAST ACROSS NORTHERN NEVADA TONIGHT WITH A FEW SHOWERS POSSIBLE NORTH OF I-80. THE BEST FORCING WILL BE JUST NORTH OF THE COLD FRONT ALONG A PORTOLA TO LOVELOCK LINE FROM 8-MIDNIGHT THIS EVENING. IT IS HERE WHERE THE BEST CHANCE OF SHOWERS WILL LIE WITH ISOLATED SHOWERS POSSIBLE ELSEWHERE NORTH OF HIGHWAY 50 TONIGHT. WINDS BEHIND THE FRONT WILL BECOME NORTH AND A BIT BREEZY WITH SOME BLOWING DUST POSSIBLE OFF THE CARSON/HUMBOLDT SINKS EAST OF HIGHWAY 95. THESE NORTH WINDS WILL REINFORCE THE COLD AIR ACROSS THE EASTERN SIERRA AND WESTERN NEVADA WITH TEMPS REMAINING BELOW NORMAL THURSDAY. A COLD NIGHT IS EXPECTED THURSDAY NIGHT UNDER MAINLY CLEAR SKIES AND LIGHT WINDS. WIDESPREAD 20S ARE EXPECTED ALONG THE SIERRA FRONT WITH TEENS IN THE SIERRA VALLEYS AND IN PARTS OF PERSHING COUNTY. THESE WILL BE THE COLDEST LOWS WE HAVE SEEN SINCE EARLY MARCH. SOME RIDGING FRIDAY WITH A WARMING TREND BEFORE A SIGNIFICANT TROUGH APPROACHES FOR THE WEEKEND. IT WILL BE BREEZY AND MILD SATURDAY AHEAD OF THE SYSTEM WITH INCREASING CLOUDS. AT THIS POINT, WITH 700 MB WINDS AROUND 25-30 KTS AND A MODERATE SURFACE GRADIENT, PEAK GUSTS LOOK TO BE 35-45 MPH ACROSS NORTHEAST CA AND WESTERN NV. ANY THREAT OF PRECIPITATION LOOKS TO HOLD OFF UNTIL SATURDAY NIGHT, AND ITS EXACT TIMING REMAINS UNCERTAIN. WALLMANN .LONG TERM...SUNDAY THROUGH WEDNESDAY... CHANCES ARE INCREASING FOR A COLDER PATTERN WITH RAIN AND SNOW LATE THIS WEEKEND INTO EARLY NEXT WEEK. TWO SYSTEMS LOOK TO IMPACT THE REGION, THE FIRST SUNDAY AND SUNDAY NIGHT FOLLOWED BY A SECOND SYSTEM IN THE TUESDAY TIMEFRAME. THESE ARE LOOKING TO BE TYPICAL SPRING SEASON CLOSED LOW SYSTEMS THAT WILL PROVIDE A SHOT OF COLDER AIR WHICH COULD LOWER SNOW LEVELS BETWEEN 4,000-5,000 FEET. AS SUCH, THOSE WITH TRAVEL PLANS SUNDAY THROUGH EARLY NEXT WEEK SHOULD MONITOR THE FORECAST FOR POTENTIAL TRAVEL IMPACTS. MAIN CHANGES IN THE FORECAST FOR SUNDAY WERE TO INCREASE PRECIPITATION CHANCES AS THE LATEST RUNS OF THE GFS AND EC ARE NOW SHOWING SOLID AGREEMENT. THE TREND HAS BEEN TO DIG THIS SYSTEM FARTHER SOUTH PROVIDING POTENTIAL FOR SNOWFALL ACROSS THE SIERRA AS EARLY AS SUNDAY MORNING. THERE IS NO BIG MOISTURE TAP WITH THIS SYSTEM AND DO NOT EXPECT ANY SIGNIFICANT SNOWFALL AMOUNTS BUT SOME PRELIMINARY LIQUID EQUIVALENT AMOUNTS AROUND A QUARTER TO A THIRD OF AN INCH ARE POSSIBLE ALONG THE SIERRA CREST. SNOW LEVELS SHOULD LOWER BELOW 5,000 FEET WHICH MAY PRESENT SOME TRAVEL IMPACTS SUNDAY WHERE A FEW INCHES OF SNOWFALL WILL BE POSSIBLE. IMPACTS MAY BE LIMITED SUNDAY AS ROAD TEMPERATURES AND APRIL SUN ANGLE MAY LIMIT ROADWAY ACCUMULATIONS. NONETHELESS WET AND SLICK ROADWAYS SEEM LIKELY. SHOWER ACTIVITY DIMINISHES BY MONDAY MORNING WITH A BREAK BETWEEN THE NEXT SYSTEM WHICH LOOKS TO PUSH INTO THE SIERRA BY TUESDAY MORNING. THIS SYSTEM MAY HAVE A BETTER CHANCE TO SPREAD SHOWERS ACROSS WESTERN NEVADA BUT AGAIN NO BIG MOISTURE TAP IS EXPECTED WITH THIS LOW. UNCERTAINTY IS HIGHER WITH THIS SYSTEM AS RUN CONSISTENCY, ENSEMBLE SPREADS, AND DETERMINISTIC MODEL AGREEMENT IS ONLY NOW SHOWING SOME IMPROVEMENT. AT THIS POINT THE TAKE AWAY WOULD BE THAT THIS SHOULD BE ANOTHER COLDER SYSTEM WHICH MAY PROVIDE SOME RAIN AND SNOW SHOWERS TUESDAY WHICH MAY CREATE SOME TRAVEL IMPACTS. 700 MB TEMPS LOOKING TO BE IN THE -7C TO -9C RANGE WHICH CLOUD KEEP SNOW LEVELS AROUND 5,000 FEET. INCREASED WINDS WILL ACCOMPANY EACH OF THESE SYSTEMS WITH SOME HAZARDOUS BOATING CONDITIONS POSSIBLE BY THE END OF THE WEEKEND INTO EARLY NEXT WEEK. THE STRONGER PERIODS OF WIND LOOKS TO BE SUNDAY AND TUESDAY AS EACH OF THE LOW PRESSURE SYSTEMS PUSH THROUGH THE REGION. FUENTES && .AVIATION... A WEAK DISTURBANCE WILL BRUSH THROUGH WESTERN NEVADA TONIGHT WITH VFR CONDITIONS EXPECTED AND GENERALLY LESS THAN 15% CHANCE FOR A SHOWER ACROSS KRNO AND KCXP. THE WEAK DISTURBANCE WILL MAINLY ACT TO REINFORCE BREEZY NORTHEAST WINDS OVERNIGHT WITH GUSTS OF 20-25 KNOTS EXPECTED. FUENTES && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
351 AM MDT THU APR 2 2015 .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 351 AM MDT THU APR 2 2015 WATER VAPOR SATELLITE IMAGERY IS SHOWING AN UPPER LEVEL TROUGH MOVING ACROSS NEVADA AT THIS TIME. IN ADDITION TO THE TROUGH...CAN SEE CLOUD ENHANCEMENT OVER UTAH AND NORTHWEST COLORADO THAT IS ASSOCIATED WITH THE LEFT EXIT REGION OF THE JET. AS THIS SYSTEM SHIFTS EASTWARD TODAY...IT WILL BRING MOSTLY SNOW TO NORTHEAST COLORADO. IT APPEARS THIS SYSTEM IS A LITTLE BIT FARTHER NORTH THAN FORECASTED 24 HOURS AGO. EVEN THE LATEST HRRR AND RAP CONTINUE THE TREND NORTHWARD WHERE THE MAIN PRECIPITATION IS STILL NORTH OF DENVER THROUGH MOST OF THE AFTERNOON. COLD AIR IS EXPECTED TO REMAIN ALONG THE FRONT RANGE THIS MORNING DUE TO EASTERLY UPSLOPE WINDS...KEEPING THE CHANCE FOR A RAIN SNOW MIX. NORTHERLY WINDS WILL INCREASE THIS AFTERNOON AS A SURFACE LOW DEEPENS OVER SOUTHERN COLORADO. EXPECT ENOUGH COLD AIR BEHIND THE NORTHERLY SURGE FOR PRECIPITATION TO CHANGE ALL TO SNOW WITH TEMPERATURES HOVERING AROUND FREEZING. RIGHT NOW ITS LOOKING LIKE THE BEST LIFT WILL BE FROM DENVER NORTH...SO WILL HAVE TO THE HIGHEST POPS THIS AFTERNOON FOR THIS AREA. PRECIPITATION IS EXPECTED TO SPREAD SOUTH AND EAST THIS EVENING AS UPSLOPE DEEPENS AND LIFT ALOFT SPREADS EAST. WITH THIS SYSTEM BEING QUICK MOVING AND TRENDING A LITTLE FARTHER NORTH...EXPECT SNOWFALL AMOUNTS TO REMAIN BELOW ADVISORY CRITERIA EVEN IN THE NORTHERN FOOTHILLS AND MOUNTAINS. SNOWFALL AMOUNTS OF 3 TO 7 IS EXPECTED IN THE FOOTHILLS WITH 1 TO 5 INCHES ALONG THE FRONT RANGE AND PARTS OF THE PLAINS. HEAVY AMOUNTS WILL BE FOUND TO THE NORTH. DUE TO APRIL SUN AND WARM GROUND TEMPERATURES...MOST OF THE ACCUMULATION SHOULD OCCUR ON GRASSY SURFACES. SOME SLUSHY ROADS WILL BE POSSIBLE UNDER THE AREAS OF HEAVIER SNOW AND ALSO THIS EVENING AS TEMPERATURES COOL. SNOW IS EXPECTED TO DECREASE LATE THIS EVENING AS THIS SYSTEM MOVES EAST OF THE REGION. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 351 AM MDT THU APR 2 2015 THE UPPER LEVEL TROUGH WILL MOVE EAST BY FRIDAY AFTERNOON WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NW. THIS WILL HELP TO TURN WINDS MORE WESTERLY THAT WILL AID IN INCREASING DOWNSLOPE BRINGING PRECIPITATION TO AN END. ISOLATED SHOWERS WILL STILL LINGER INTO FRIDAY MORNING BUT WILL QUICKLY DIMINISH BY THE AFTERNOON. MID LEVEL MOISTURE WILL DEGRADE THROUGH THE DAY WITH COOLER AIR STICKING AROUND KEEPING HIGHS ON FRIDAY IN THE 40S. TEMPERATURES WILL REBOUND TO ABOVE NORMAL FOR THE WEEKEND WITH UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE IN PLACE. HIGHS ON SATURDAY WILL GET INTO THE LOWER 60S WITH SUNDAY HAVING THE POTENTIAL OF LOWER 70S UNDER MOSTLY SUNNY SKIES. SUNDAY NIGHT INTO MONDAY UPPER LEVEL FLOW WILL SWITCH FROM WESTERLY TO SOUTHWESTERLY AHEAD OF THE NEXT UPPER LEVEL TROUGH. A WEAK TROUGH WILL PUSH THROUGH MONDAY AFTERNOON BRINGING COOLER TEMPERATURES AND INCREASING CLOUDS TO THE REGION. FOR TUESDAY INTO WEDNESDAY A ELONGATED UPPER LEVEL TROUGH WILL BE OVER THE PACIFIC NW MOVING EAST INTO THE GREAT BASIN. THIS WILL BRING A SLIGHT CHANCE OF PRECIPITATION TO NE COLORADO TUESDAY EVENING THROUGH WEDNESDAY. DETAILS ARE SCARCE AS THIS SYSTEM IS STILL A FEW DAYS AWAY BUT WILL CONTINUE TO MONITOR MODEL TRENDS. && .AVIATION...(FOR THE TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 351 AM MDT THU APR 2 2015 CEILINGS OF 2000 TO 4000 FEET ARE EXPECTED AROUND 12Z. THEY WILL THEN LOWER THROUGH MORNING HOURS. RAIN AND SNOW SHOWERS WILL BE POSSIBLE BEFORE 18Z. BETWEEN 18Z TO 20Z...A COLD FRONT WILL PUSH THROUGH AND CAUSE NORTHERLY WINDS TO INCREASE WITH GUSTS TO 30 KNOTS POSSIBLE. THIS WILL COOL THE AIRMASS ENOUGH THAT PRECIPITATION IS EXPECTED TO QUICKLY TURN TO SNOW BEHIND THE FRONT. BEST CHANCE FOR SNOW WILL BE DURING ABOUT 21Z TO 03Z. EXPECT VISIBILITY TO BE AROUND A MILE IN THE SNOW AND OCCASIONALLY FALL TO A QUARTER MILE UNDER THE HEAVIER SNOW. CONDITIONS ARE EXPECTED TO IMPROVE AFTER 03Z AS THIS SYSTEM STARTS TO SHIFT OFF TO THE EAST. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...MEIER LONG TERM...BOWEN AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
406 AM EDT THU APR 2 2015 .SYNOPSIS... ISSUED AT 400 AM EDT THU APR 2 2015 RAIN IS EXPECTED TO SPREAD ACROSS THE REGION TODAY AHEAD OF A COLD FRONT. THUNDERSTORMS WILL ALSO BE POSSIBLE AT TIMES. HIGH TEMPERATURES WILL GENERALLY BE IN THE 60S. RAIN WILL CONTINUE TONIGHT NEAR AND SOUTH OF THE FRONT AS IT SAGS INTO CENTRAL PORTIONS OF ILLINOIS...INDIANA AND OHIO. LOWS WILL RANGE FROM THE MIDDLE AND UPPER 30S NORTH TO THE UPPER 40S SOUTH. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 359 AM EDT THU APR 2 2015 UPSTREAM RADAR IS STILL PRETTY BENIGN...BUT HI RES GUIDANCE INCLUDING THE HRRR CONTINUE SHOW INCREASING COVERAGE OF SCATTERED SHOWERS AND TSTORMS BETWEEN NOW AND DAYBREAK ALONG THE LEADING EDGE OF 850MB MOISTURE ADVECTION ASSOCIATED WITH THE MID LEVEL WAVE CURRENTLY LOCATED NEAR SAINT LOUIS. THIS WAVE OF CONVECTION WILL BE OUT OF THE AREA BY MID DAY...BUT WILL QUICKLY BE REPLACED BY ADDITIONAL CONVECTION ASSOCIATED WITH THE OUTFLOW BOUNDARY/SYNOPTIC COLD FRONT MOVING OUT OF THE UPPER MIDWEST. LATEST SPC OUTLOOK HAS THE SOUTHERN HALF OF OUR FORECAST AREA IN A MARGINAL RISK FOR SEVERE WEATHER. THIS RISK SEEMS APPROPRIATE GIVEN THE CONDITIONAL THREAT. SURFACE DEWPOINTS WILL INCREASE INTO THE UPPER 50S BY MID DAY...BUT MEAGER MID-LEVEL LAPSE RATES...AND LIMITED SURFACE HEATING WILL LIMIT SEVERE POTENTIAL. CURRENT SATELLITE VIEW SHOWS THE CLOUDCOVER ASSOCIATED WITH THE MCS IN IOWA WILL BE RIGHT ON THE HEELS OF THE MID LEVEL WAVE MOVING THROUGH ILLINOIS...THUS PROVIDING LITTLE TIME FOR MUCH SOLAR INSOLATION. IF BREAKS IN THE CLOUDS DO OCCUR...A LOW END SEVERE WIND THREAT MAY MATERIALIZE GIVEN THE 35 TO 40 KNOTS OF DEEP LAYER SHEAR AND ~40 KNOTS OF FLOW ~2500 FEET OFF THE DECK. THURSDAY WILL BE WINDY WITH GUSTS TO 25 TO 30 MPH. IF AFOREMENTIONED BREAKS IN THE CLOUDS OCCUR...THIS WILL ALLOW FOR DEEPER MIXING AND STRONGER WIND GUSTS OF 35 TO 40 MPH. WINDS WILL DIE DOWN SIGNIFICANTLY BY THE EVENING HOURS ONCE THE COLD FRONT SLIDES THROUGH THE AREA. && .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 359 AM EDT THU APR 2 2015 SECONDARY WAVE WILL BE MOVING THROUGH THE REGION FRIDAY. MAIN FRONTAL BOUNDARY WILL BE TO OUR SOUTH BUT MOISTURE ADVECTION WILL SPREAD NORTH AND SHOULD SEE PCPN RE-DEVELOP ESPECIALLY OVER SOUTH AND SOUTHEAST DURING THE AFTERNOON. COUPLED UPPER LEVEL JET TO PROVIDE GOOD DIFFLUENCE ALOFT AND HAVE CONTINUED CATEGORICAL POPS SOUTH. THERMAL PROFILES STILL SUPPORT MAINLY RAIN ON FRIDAY. HOWEVER...TEMP PROFILES DO BEGIN TO HINT AT POSSIBLE WET SNOW MIX IF STRONG LIFT IS SUFFICIENT TO COOL LOWER LEVELS IN AFTERNOON. THIS TIMING IS NOT FAVORABLE GIVEN TIME OF YEAR AND WITH WARM BOUNDARY LAYER PREFER TO HOLD OFF ANY SNOW MENTION UNTIL EVENING HOURS WHEN COLDER AIR DEEPENS. AS PREVIOUSLY MENTIONED THIS WILL COINCIDE WITH DEEPER MOISTURE EXITING THE AREA SO NOT EXPECTING ANY ACCUMS AT THIS TIME. HIGH PRESSURE MOVES BACK IN FOR SATURDAY. WARM FRONT WILL BEGIN TO TAKE SHAPE OVER THE GREAT LAKES SATURDAY NIGHT INTO SUNDAY. THIS BOUNDARY TO BECOME PROBLEMATIC FOR REMAINDER OF FORECAST AS DEEPER SOUTHWEST FLOW DEVELOPS AND FRONT BECOMES QUASI STATIONARY OVER THE AREA AS TYPICAL FOR THIS TIME OF YEAR. OBVIOUS PROBLEMS SURROUND STRONG THERMAL CONTRAST ACROSS THIS BOUNDARY AND TEMP/POP FORECAST DEPENDENT ON ITS LOCATION. STAYED CLOSE TO PREVIOUS FORECAST FOR CONSISTENCY WITH FEW CHANGES TO THE LATER PERIODS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 131 AM EDT THU APR 2 2015 LITTLE CHANGE TO THE PREVIOUS TAFS. MODEL GUIDANCE CONTINUES TO INDICATE AN INCREASING COVERAGE OF ELEVATED CONVECTION TOWARDS DAYBREAK AS THE BETTER 850MB MOISTURE ARRIVES BY 09Z ASSOCIATED WITH THE WAVE CURRENTLY MOVING OUT OF MISSOURI. ONCE THIS CONVECTIONS PUSHES THROUGH THE AREA...THERE MAY BE A LULL DURING THE LATE MORNING BEFORE CONVECTION FIRES DURING THE AFTERNOON. HANDLED PERIOD OF LOWER CIG/VISBY IN THE WAKE OF THIS CONVECTION WITH A 4 HOUR TEMPO GROUP. BRIEF PERIOD OF LLWS POSSIBLE NEAR DAYBREAK AS THE LOW LEVEL JET NEARS 60 KNOTS ACROSS THE AREA. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ043- 046. && $$ SYNOPSIS...LASHLEY SHORT TERM...BENTLEY LONG TERM...LASHLEY AVIATION...BENTLEY VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
320 AM EDT THU APR 2 2015 .UPDATE... THE LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 240 AM EST THU APR 2 2015 UNSETTLED WEATHER EXPECTED THROUGH FRIDAY NIGHT AS A FRONTAL SYSTEM DROPS SOUTHEAST ACROSS THE OHIO VALLEY. THUNDERSTORMS WILL RETURN EARLY NEXT WEEK AS WELL WITH ANOTHER SYSTEM. THERE COULD BE A FEW SEVERE STORMS TODAY AND THIS EVENING AS WELL AS NEXT WEEK. HEAVY RAIN IS ALSO POSSIBLE AT TIMES THROUGH FRIDAY. MEANWHILE...HIGH PRESSURE WILL RESULT IN DRY BUT COOLER WEATHER SATURDAY AND SUNDAY. && .NEAR TERM /TODAY THROUGH FRIDAY NIGHT/... ISSUED AT 240 AM EDT THU APR 2 2015 MAIN FOCUS FOR THE NEAR TERM WILL BE THUNDERSTORMS TODAY THROUGH FRIDAY ALONG WITH POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND EVENING AND HEAVY RAIN THIS AFTERNOON THROUGH FRIDAY. DETERMINISTIC MODELS STILL HAVE TIMING DIFFERENCES REGARDING UPPER AND SURFACE WAVES AND CONSEQUENTLY TIMING OF THE COLD FRONT...THAT WAS OVER THE UPPER MIDWEST AND SOUTHERN PLAINS THIS OVERNIGHT. HOWEVER...THE DIFFERENCES IN THE 00Z RUN THIS EVENING...SAVE THE NAM...ARE NOT AS GREAT AS THEY ONCE WERE. THE 00Z GFS IS TRENDING FURTHER NORTH WITH ITS TRACK OF SURFACE WAVES AND THEREFORE FRONTAL POSITION ON FRIDAY PER THE STEADIER 12Z ECMWF. A FEW GEFS MEMBERS WERE CLOSE TO THE OPERATIONAL 12Z ECMWF AS WAS ECMWF ENSEMBLE MEAN. MEANWHILE...THE 00Z CANADIAN IS A BIT QUICKER WITH THE FRONT...ALBEIT SLOWER WITH THE UPSTREAM TROUGH. OVERALL...FEEL A BLEND OF THE 00Z GFS...12Z ECMWF AND 12Z ECENS LOOKS BEST. THE COLD FRONT SHOULD DROP SOUTHEAST TO NEAR MERRIVILLE AROUND 18Z THIS AFTERNOON...TO FAR NORTHERN PARTS OF CENTRAL INDIANA 00Z THIS EVENING...AND TO NEAR THE OHIO RIVER ON FRIDAY...BEFORE IT TEMPORARILY STALLS WITH THE WAVES MOVING ALONG IT. FINALLY...THE FRONT SHOULD MOVE INTO EASTERN KENTUCKY BY 00Z SATURDAY...WHICH SHOULD PUT AN END TO THE SHOWERS ACROSS WESTERN PARTS OF THE FORECAST AREA. THIS REST OF THE AREA SHOULD SEE THE SHOWERS EXIT BY 06Z SATURDAY WITH COOLER AIR MOVING IN BEHIND THE FRONT. SPC SREF ENSEMBLES WERE SHOWING INCREASING MIXED LAYER CAPE TODAY WITH NEAR 500 J/KG NEAR MUNCIE AND AROUND 1000 J/K NEAR VINCENNES AT 21Z THIS AFTERNOON. THIS INSTABILITY SHOULD GRADUALLY WANE TONIGHT WITH NIGHTFALL AND FRIDAY WITH THE FRONT MOVING SOUTHEAST. DEEP MOISTURE AND STRONG FORCING WARRANT CATEGORICAL POPS TODAY THROUGH FRIDAY. AREA OF THUNDERSTORMS...CURRENTLY OVER SOUTHEASTERN MISSOURI AND NORTHEASTERN ARKANSAS AND ASSOCIATED WITH AN UPPER WAVE...SHOULD MOVE TO VINCENNES AND TERRE HAUTE AFTER 5 AM AND EAST OF THE AREA LATE MORNING PER THE 05Z HRRR RAPID REFRESH REFLECTIVITY PROGS. THUNDERSTORMS SHOULD MOVE BACK INTO THE AREA AND OTHERS POP UP THIS AFTERNOON AHEAD OF ANOTHER UPPER WAVE AND AGAIN TONIGHT WITH ANOTHER ONE. THUNDERSTORMS SHOULD BE CONFINED TO THE FAR SOUTHERN TIER OR TWO BY FRIDAY AS THE FRONT SETTLES SOUTHEAST AND STABILITY INCREASES NORTH OF THE FRONT. FINALLY...WILL ONLY CARRY EVENING SHOWER CHANCES ACROSS EAST CENTRAL INDIANA BY FRIDAY NIGHT. REGARDING SEVERE WEATHER POTENTIAL...THE 500-1000 J/KG CAPES COMBINED WITH AROUND 200 METERS SQUARED PER SECONDS SQUARED HELICITY...PER 21Z SPC SREF ENSEMBLES...SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED SEVERE WEATHER THIS AFTERNOON...ESPECIALLY SOUTHWEST OF INDIANAPOLIS...WHERE INSTABILITY SHOULD BE GREATER. SEVERE THREAT SHOULD END THIS EVENING...ESPECIALLY NORTH OF BLOOMINGTON...WITH LOSS OF SOLAR HEATING AND BETTER SHEAR SOUTH OF THERE. OVERALL...SPC DAY1 ENHANCED RISK ACROSS SOUTHERN PARTS OF KNOX...DAVIESS AND MARTIN COUNTIES AND SLIGHT RISK ELSEWHERE OVER CENTRAL INDIANA LOOKS GOOD WITH MAIN SEVERE THREATS BEING DAMAGING WINDS AND LARGE HAIL. HOWEVER...CAN NOT RULE OUT A TORNADO OR TWO AS LIFTED CONDENSATION LEVELS ARE FORECASTED TO LESS THAN 3000 FEET. IF EVEN BRIEF BREAKS OCCUR IN THE CLOUD COVER OCCUR...THIS COULD ALSO AID IN ROTATING STORMS. RAINFALL WILL BE ANOTHER ISSUE THROUGH FRIDAY AS JET STREAKS MOVE THROUGH THE 100 PLUS KNOT UPPER JET THAT WILL BE OVER THE AREA TONIGHT AND FRIDAY...PROVIDING STRONG UPPER DIVERGENCE. JET INTERACTIONS ALONG WITH DEEP MOISTURE...DISPLAYED BY PRECIPITABLE WATER VALUES TO NEAR 1.5 INCHES...OR TWICE OR MORE ABOVE NORMAL FOR EARLY APRIL...SUGGEST HEAVY RAIN MENTION TONIGHT WITH HEAVY RAIN ALSO POSSIBLE MAINLY SOUTH OF INTERSTATE 70 ON FRIDAY. FINALLY...SHOULD SEE BREEZY CONDITIONS TODAY WITH BUFKIT SUGGESTING GUSTS TO 30 MPH OR MORE ARE POSSIBLE THIS AFTERNOON...AFTER THE INVERSION DIES. WENT WITH DAYTIME TEMPERATURES AT OR BELOW 00Z MOS DO TO THICK CLOUD COVER. ALSO...WENT CLOSER TO THE MORE MILD 00Z NAM TEMPERATURES FOR OVERNIGHT LOWS...ESPECIALLY SOUTH OF THE FRONT. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... ISSUED AT 240 AM EST FRI APR 02 2015 FOCUS FOR THE SHORT TERM WILL BE ON TEMPERATURES AS MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA. MODEL RH TIME SECTIONS AND CU DEVELOPMENT PROGS SUGGEST THERE WILL BE LITTLE CLOUD COVER AROUND ON SATURDAY WITH PERHAPS SOME CIRRUS SPILLING OVER TOP OF A MISSISSIPPI RIDGE AND ACROSS CENTRAL INDIANA SATURDAY NIGHT. 850 MILLIBAR TEMPERATURE PROGS BRING IN SUB-ZERO TEMPERATURES SATURDAY MORNING BUT WARM IT UP TO 2 TO 4 DEGREES ABOVE ZERO SATURDAY NIGHT. HOWEVER...WITH SUNNY SKIES...SIMILAR 00Z MOS... SLIGHTLY BELOW NORMAL TEMPERATURES...LOOK OK WITH HIGHS IN THE 50S AND LOWS IN THE 30S. && .LONG TERM /SUNDAY THROUGH THURSDAY/... ISSUED AT 320 AM EDT THU APR 2 2015 NUMEROUS OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE LONG TERM PERIOD AS BROAD LOW PRESSURE DEVELOPS TO THE WEST AND SLOWLY MOVES THROUGH THE REGION. THIS COULD POTENTIALLY EXACERBATE AN EXISTING HYDROLOGIC ISSUE DEPENDING ON HOW MUCH RAIN OCCURS IN THE NEXT 24 TO 48 HOURS. INSTABILITY INDICES SUGGEST THUNDER IS A POSSIBILITY IN NEARLY ALL PERIODS AND FORECAST WILL REFLECT THAT. && .AVIATION.../DISCUSSION FOR THE 02/06Z TAFS/ ISSUED AT 147 AM EDT THU APR 2 2015 VFR CONDITIONS WILL CONTINUE FOR A FEW HOURS AFTER ISSUANCE TIME BEFORE MVFR CEILINGS MOVE INTO THE AREA TOWARDS MORNING. BRIEF IFR CONDITIONS ARE NOT OUT OF THE QUESTION IN ANY HEAVY RAINFALL OR THUNDERSTORMS THROUGHOUT THE DAY ON THURSDAY. SOUTHEASTERLY WINDS AT 5-10 KTS WILL TURN MORE SOUTHERLY OVERNIGHT ADVECTING MOISTER AIR INTO THE AREA. HOWEVER...WITH DEW POINTS STILL IN THE LOW TO MID 30S AT ISSUANCE TIME...IT MAY TAKE LONGER THAN PREVIOUSLY FORECAST FOR MVFR CEILINGS AND ASSOCIATED PRECIPITATION TO REACH THE TERMINALS WHICH WILL NEED TO BE WATCHED. VAD WIND PROFILE INDICATES WINDS AROUND 2KFT AT 50KT...SUGGESTING FORECAST SOUNDINGS ARE UNDERDOING DEGREE OF LOW LEVEL WIND SHEAR OVERNIGHT. WILL CARRY SHEAR THROUGH THE MORNING WHEN GUSTS BEGIN. EVEN WITH PLENTIFUL CLOUD COVER THROUGHOUT THE DAY...THERE WILL BE ENOUGH INSTABILITY TO INCLUDE THUNDER AT ALL SITES DURING THE AFTERNOON. WINDS AROUND 15 KTS WILL TURN MORE WESTERLY THROUGHOUT THE DAY ON THURSDAY WITH GUSTS APPROACHING 30 KTS POSSIBLE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...MK SHORT TERM...MK LONG TERM...NIELD AVIATION...LEE/NIELD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
240 AM EDT THU APR 2 2015 .UPDATE... THE SYNOPSIS AND NEAR TERM SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 240 AM EST THU APR 2 2015 UNSETTLED WEATHER EXPECTED THROUGH FRIDAY NIGHT AS A FRONTAL SYSTEM DROPS SOUTHEAST ACROSS THE OHIO VALLEY. THUNDERSTORMS WILL RETURN EARLY NEXT WEEK AS WELL WITH ANOTHER SYSTEM. THERE COULD BE A FEW SEVERE STORMS TODAY AND THIS EVENING AS WELL AS NEXT WEEK. HEAVY RAIN IS ALSO POSSIBLE AT TIMES THROUGH FRIDAY. MEANWHILE...HIGH PRESSURE WILL RESULT IN DRY BUT COOLER WEATHER SATURDAY AND SUNDAY. && .NEAR TERM /TODAY THROUGH FRIDAY NIGHT/... ISSUED AT 240 AM EDT THU APR 2 2015 MAIN FOCUS FOR THE NEAR TERM WILL BE THUNDERSTORMS TODAY THROUGH FRIDAY ALONG WITH POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND EVENING AND HEAVY RAIN THIS AFTERNOON THROUGH FRIDAY. DETERMINISTIC MODELS STILL HAVE TIMING DIFFERENCES REGARDING UPPER AND SURFACE WAVES AND CONSEQUENTLY TIMING OF THE COLD FRONT...THAT WAS OVER THE UPPER MIDWEST AND SOUTHERN PLAINS THIS OVERNIGHT. HOWEVER...THE DIFFERENCES IN THE 00Z RUN THIS EVENING...SAVE THE NAM...ARE NOT AS GREAT AS THEY ONCE WERE. THE 00Z GFS IS TRENDING FURTHER NORTH WITH ITS TRACK OF SURFACE WAVES AND THEREFORE FRONTAL POSITION ON FRIDAY PER THE STEADIER 12Z ECMWF. A FEW GEFS MEMBERS WERE CLOSE TO THE OPERATIONAL 12Z ECMWF AS WAS ECMWF ENSEMBLE MEAN. MEANWHILE...THE 00Z CANADIAN IS A BIT QUICKER WITH THE FRONT...ALBEIT SLOWER WITH THE UPSTREAM TROUGH. OVERALL...FEEL A BLEND OF THE 00Z GFS...12Z ECMWF AND 12Z ECENS LOOKS BEST. THE COLD FRONT SHOULD DROP SOUTHEAST TO NEAR MERRIVILLE AROUND 18Z THIS AFTERNOON...TO FAR NORTHERN PARTS OF CENTRAL INDIANA 00Z THIS EVENING...AND TO NEAR THE OHIO RIVER ON FRIDAY...BEFORE IT TEMPORARILY STALLS WITH THE WAVES MOVING ALONG IT. FINALLY...THE FRONT SHOULD MOVE INTO EASTERN KENTUCKY BY 00Z SATURDAY...WHICH SHOULD PUT AN END TO THE SHOWERS ACROSS WESTERN PARTS OF THE FORECAST AREA. THIS REST OF THE AREA SHOULD SEE THE SHOWERS EXIT BY 06Z SATURDAY WITH COOLER AIR MOVING IN BEHIND THE FRONT. SPC SREF ENSEMBLES WERE SHOWING INCREASING MIXED LAYER CAPE TODAY WITH NEAR 500 J/KG NEAR MUNCIE AND AROUND 1000 J/K NEAR VINCENNES AT 21Z THIS AFTERNOON. THIS INSTABILITY SHOULD GRADUALLY WANE TONIGHT WITH NIGHTFALL AND FRIDAY WITH THE FRONT MOVING SOUTHEAST. DEEP MOISTURE AND STRONG FORCING WARRANT CATEGORICAL POPS TODAY THROUGH FRIDAY. AREA OF THUNDERSTORMS...CURRENTLY OVER SOUTHEASTERN MISSOURI AND NORTHEASTERN ARKANSAS AND ASSOCIATED WITH AN UPPER WAVE...SHOULD MOVE TO VINCENNES AND TERRE HAUTE AFTER 5 AM AND EAST OF THE AREA LATE MORNING PER THE 05Z HRRR RAPID REFRESH REFLECTIVITY PROGS. THUNDERSTORMS SHOULD MOVE BACK INTO THE AREA AND OTHERS POP UP THIS AFTERNOON AHEAD OF ANOTHER UPPER WAVE AND AGAIN TONIGHT WITH ANOTHER ONE. THUNDERSTORMS SHOULD BE CONFINED TO THE FAR SOUTHERN TIER OR TWO BY FRIDAY AS THE FRONT SETTLES SOUTHEAST AND STABILITY INCREASES NORTH OF THE FRONT. FINALLY...WILL ONLY CARRY EVENING SHOWER CHANCES ACROSS EAST CENTRAL INDIANA BY FRIDAY NIGHT. REGARDING SEVERE WEATHER POTENTIAL...THE 500-1000 J/KG CAPES COMBINED WITH AROUND 200 METERS SQUARED PER SECONDS SQUARED HELICITY...PER 21Z SPC SREF ENSEMBLES...SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED SEVERE WEATHER THIS AFTERNOON...ESPECIALLY SOUTHWEST OF INDIANAPOLIS...WHERE INSTABILITY SHOULD BE GREATER. SEVERE THREAT SHOULD END THIS EVENING...ESPECIALLY NORTH OF BLOOMINGTON...WITH LOSS OF SOLAR HEATING AND BETTER SHEAR SOUTH OF THERE. OVERALL...SPC DAY1 ENHANCED RISK ACROSS SOUTHERN PARTS OF KNOX...DAVIESS AND MARTIN COUNTIES AND SLIGHT RISK ELSEWHERE OVER CENTRAL INDIANA LOOKS GOOD WITH MAIN SEVERE THREATS BEING DAMAGING WINDS AND LARGE HAIL. HOWEVER...CAN NOT RULE OUT A TORNADO OR TWO AS LIFTED CONDENSATION LEVELS ARE FORECASTED TO LESS THAN 3000 FEET. IF EVEN BRIEF BREAKS OCCUR IN THE CLOUD COVER OCCUR...THIS COULD ALSO AID IN ROTATING STORMS. RAINFALL WILL BE ANOTHER ISSUE THROUGH FRIDAY AS JET STREAKS MOVE THROUGH THE 100 PLUS KNOT UPPER JET THAT WILL BE OVER THE AREA TONIGHT AND FRIDAY...PROVIDING STRONG UPPER DIVERGENCE. JET INTERACTIONS ALONG WITH DEEP MOISTURE...DISPLAYED BY PRECIPITABLE WATER VALUES TO NEAR 1.5 INCHES...OR TWICE OR MORE ABOVE NORMAL FOR EARLY APRIL...SUGGEST HEAVY RAIN MENTION TONIGHT WITH HEAVY RAIN ALSO POSSIBLE MAINLY SOUTH OF INTERSTATE 70 ON FRIDAY. FINALLY...SHOULD SEE BREEZY CONDITIONS TODAY WITH BUFKIT SUGGESTING GUSTS TO 30 MPH OR MORE ARE POSSIBLE THIS AFTERNOON...AFTER THE INVERSION DIES. WENT WITH DAYTIME TEMPERATURES AT OR BELOW 00Z MOS DO TO THICK CLOUD COVER. ALSO...WENT CLOSER TO THE MORE MILD 00Z NAM TEMPERATURES FOR OVERNIGHT LOWS...ESPECIALLY SOUTH OF THE FRONT. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... ISSUED AT 240 AM EST FRI APR 02 2015 FOCUS FOR THE SHORT TERM WILL BE ON TEMPERATURES AS MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA. MODEL RH TIME SECTIONS AND CU DEVELOPMENT PROGS SUGGEST THERE WILL BE LITTLE CLOUD COVER AROUND ON SATURDAY WITH PERHAPS SOME CIRRUS SPILLING OVER TOP OF A MISSISSIPPI RIDGE AND ACROSS CENTRAL INDIANA SATURDAY NIGHT. 850 MILLIBAR TEMPERATURE PROGS BRING IN SUB-ZERO TEMPERATURES SATURDAY MORNING BUT WARM IT UP TO 2 TO 4 DEGREES ABOVE ZERO SATURDAY NIGHT. HOWEVER...WITH SUNNY SKIES...SIMILAR 00Z MOS... SLIGHTLY BELOW NORMAL TEMPERATURES...LOOK OK WITH HIGHS IN THE 50S AND LOWS IN THE 30S. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ISSUED AT 224 PM EDT WED APR 1 2015 INITIALLY QUIET WEATHER IS EXPECTED AS THE WEEKEND ENDS AS HIGH PRESSURE DEPARTS THE AREA. AN ACTIVE WEATHER PATTERN IS EXPECTED TO TAKE OVER ON MONDAY THROUGH WEDNESDAY AS THE GFS AND ECMWF SHOW WARMER AND MORE SOUTHERLY FLOW DEVELOPING FOR THE OHIO VALLEY THROUGH THE MIDDLE OF THE WEEK. SEVERAL SHORT WAVES ARE EXPECTED TO PUSH THROUGH THE OHIO VALLEY ON MONDAY THROUGH WEDNESDAY WITH GOOD MOISTURE IN PLACE AT THE SURFACE. FURTHERMORE...LOWER LEVEL FEATURES ON MONDAY SUGGEST CENTRAL INDIANA WILL REMAIN FIRMLY IN THE WARM SECTOR OF AN APPROACHING LOW PRESSURE SYSTEM ALONG WITH FAVORABLE WARM AIR ADVECTION AND MOISTURE ARRIVING. BY TUESDAY AND WEDNESDAY...THE ACCOMPANYING COLD FRONT TRAILING THE LOW REACHES OF INDIANA AS LOW PRESSURE MOVES TO THE EASTERN GREAT LAKES. GFS AND ECMWF DIFFER ON THE PROGRESS OF THE FRONT...BUT HINT AT IT BEING IN THE AREA PROVIDING A FOCUS FOR LOWER LEVEL CONVERGENCE. THUS HAVE INCLUDED POPS THROUGH TUESDAY AND WEDNESDAY. && .AVIATION.../DISCUSSION FOR THE 02/06Z TAFS/ ISSUED AT 147 AM EDT THU APR 2 2015 VFR CONDITIONS WILL CONTINUE FOR A FEW HOURS AFTER ISSUANCE TIME BEFORE MVFR CEILINGS MOVE INTO THE AREA TOWARDS MORNING. BRIEF IFR CONDITIONS ARE NOT OUT OF THE QUESTION IN ANY HEAVY RAINFALL OR THUNDERSTORMS THROUGHOUT THE DAY ON THURSDAY. SOUTHEASTERLY WINDS AT 5-10 KTS WILL TURN MORE SOUTHERLY OVERNIGHT ADVECTING MOISTER AIR INTO THE AREA. HOWEVER...WITH DEW POINTS STILL IN THE LOW TO MID 30S AT ISSUANCE TIME...IT MAY TAKE LONGER THAN PREVIOUSLY FORECAST FOR MVFR CEILINGS AND ASSOCIATED PRECIPITATION TO REACH THE TERMINALS WHICH WILL NEED TO BE WATCHED. VAD WIND PROFILE INDICATES WINDS AROUND 2KFT AT 50KT...SUGGESTING FORECAST SOUNDINGS ARE UNDERDOING DEGREE OF LOW LEVEL WIND SHEAR OVERNIGHT. WILL CARRY SHEAR THROUGH THE MORNING WHEN GUSTS BEGIN. EVEN WITH PLENTIFUL CLOUD COVER THROUGHOUT THE DAY...THERE WILL BE ENOUGH INSTABILITY TO INCLUDE THUNDER AT ALL SITES DURING THE AFTERNOON. WINDS AROUND 15 KTS WILL TURN MORE WESTERLY THROUGHOUT THE DAY ON THURSDAY WITH GUSTS APPROACHING 30 KTS POSSIBLE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...MK SHORT TERM...MK LONG TERM...PUMA AVIATION...LEE/NIELD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
322 AM CDT THU APR 2 2015 .SYNOPSIS... ISSUED AT 232 AM CDT THU APR 2 2015 AT 300 AM CDT...A COLD FRONT HAD PUSHED INTO CENTRAL IOWA. MORE FAVORABLE MOISTURE AHEAD OF THE BOUNDARY HAD FINALLY MADE IT INTO EASTERN IOWA...WITH DEWPOINTS IN THE LOW/MID 50S. SHOWERS/SCATTERED THUNDERSTORMS ALONG AND EAST OF THE FRONT WERE MOVING INTO THE FAR WESTERN FRINGE OF THE FORECAST AREA...FUELED BY A RIBBON OF MU CAPE AOA 500 J/KG AND A SWATH OF STEEPER MID LEVEL LAPSE RATE. A SHORT WAVE TROUGH LIFTING THROUGH ILLINOIS IS SUPPORTING ISOLATED CONVECTION ACROSS THE FAR EASTERN COUNTIES. EARLY MORNING TEMPERATURES WERE IN THE 50S TO LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 232 AM CDT THU APR 2 2015 THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS PRECIP TRENDS/COVERAGE/AMOUNTS THROUGH EARLY AFTERNOON. IN THE NEAR TERM...HIGH RESOLUTION MODELS INCLUDING THE HRRR AND ARW/NMM ARE RUNNING A BIT SLOW BUT OTHERWISE HAVE THE CURRENT WEATHER MODELED WELL. HAVE ADJUSTED POPS FOR NEAR TERM TRENDS. HIGHEST QPF THROUGH 12Z WILL BE FOCUSED ACROSS THE WEST AND THE FAR EASTERN FRINGE...WITH SPOTTIER RAIN COVERAGE CENTRAL. AFTER 12Z...HIGHEST QPF AND SHOWER/STORM COVERAGE SHOULD BE LOCATED ALONG/EAST OF THE MISSISSIPPI RIVER AS THE UPSTREAM SHORTWAVE INTERACTS WITH THE COLD FRONT. TOTAL QPF NOW LOOKS LIKE IT WILL FALL MAINLY IN THE TENTH TO THIRD OF AN INCH RANGE. THE CHANCE OF ANY SEVERE WEATHER IS VIRTUALLY NIL. RAIN WILL END IN THE SOUTHEAST/EAST DURING THE EARLY AFTERNOON. BLENDED TEMPERATURE GUIDANCE IN THE MID/UPPER 60S FOR AFTERNOON HIGHS LOOKS REASONABLE. FOR TONIGHT...SOME LIGHT RAIN MAY SPREAD INTO THE WEST LATE...AHEAD OF ANOTHER WEAK SHORTWAVE TROUGH. EXPECT LOWS IN THE UPPER 30S/MID 40S. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 232 AM CDT THU APR 2 2015 AN ACTIVE WEATHER PATTERN FOR THE LONG TERM IS THE MAIN FORECAST CONCERN. THE BEGINNING OF THE PERIOD SEES ONE SYSTEM WITH NUMEROUS FORECAST ISSUES MOVING OUT OF THE AREA...FOLLOWED BY A FEW QUICK SYSTEMS...THEN AN ACTIVE WEEK NEXT WEEK WITH NUMEROUS SYSTEMS AND CHANCES FOR RAIN. LIKE ADVERTISED LAST NIGHT IN THE AFD...A COLD FRONT STALLS OUT TO OUR SOUTH AS THE MAIN FORCING MOVES QUICKLY TO THE EAST. AT THE SAME TIME ANOTHER WAVE IS MOVING ACROSS THE CENTRAL UNITED STATES. THIS WAVE INTERACTS WITH THE SURFACE FRONT...BRINGING IT SLIGHTLY NORTH AND THEN INDUCING SURFACE CYCLOGENESIS AND MOVING THE FRONT OUT OF THE AREA. THE GEM AND THE GFS ARE THE TWO MODELS WITH THE MOST PRECIP NORTH INTO OUR AREA. WHILE TEMPERATURES WILL BE WELL ABOVE FREEZING...THE SREF MEAN SUGGESTS THAT THE TEMPS IN EARLY AFTERNOON WILL BE CONDUCIVE TO SNOWFALL. THE REST OF THE DETERMINISTIC MODELS HAVE US ABOVE FREEZING. THE OPERATIONAL NAM...A MEMBER OF THE SREF...HAS NO QPF FOR US DURING THIS TIME. SO THERE IS A LARGE SPREAD IN THE MEMBERS IN THE SREF. THINK THE SREF MEAN IS BEING SWAYED HEAVILY BY ONE MEMBER...SO DONT THINK WE WILL SEE SNOW. FRIDAY EVENING THROUGH SUNDAY AFTERNOON LOOKS TO BE DRY FOR OUR AREA. ANOTHER CLIPPER MOVES THROUGH WISCONSIN. LATEST RUNS BRING THE QPF WITH THIS SYSTEM FURTHER NORTH...SO ONLY OUR FAR NORTHERN ZONES HAVE A SLIGHT CHANCE FOR POPS. WITH THE THERMAL PROFILE IT APPEARS THAT RASN MIX WOULD BE PREFERRED FOR ANY PRECIP THAT FALLS. MONDAY THROUGH TUESDAY EVENING...AN ACTIVE PATTERN SETS UP OVER THE AREA AND IT LOOKS LIKE WE SEE QPF THROUGH THE PERIOD. MODELS ARE IN AGREEMENT IN THE OVERALL LARGE SCALE PATTERN...HOWEVER THE FINESCALE FEATURES ARE YET TO BE AGREED UPON. IT LOOKS LIKE THE BEST CHANCE FOR THUNDER AT THIS TIME WILL BE MONDAY AFTERNOON THROUGH THE NIGHT. WEDNESDAY AND THURSDAY...THE MODELS HAVE FLIP FLOPPED ON LARGE SCALE FEATURES AND ARE DIFFERENT IN SOLUTIONS WITH THE ECMWF BEING WET AND THE GFS BEING DRY. OBVIOUSLY AS WE GET CLOSER THIS WILL BE THE NEXT FORECAST CONCERN BY EARLY NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1152 PM CDT WED APR 1 2015 COLD FRONT AND LINE OF SHOWERS AND THUNDERSTORMS MOVING INTO CENTRAL IA LATE TONIGHT WILL ADVANCE THROUGH THE TERMINALS LATE TONIGHT INTO THE EARLY MORNING HOURS THURSDAY. AHEAD OF THE FRONT...GUSTY SOUTH WINDS WILL CONTINUE AT THE SURFACE. NEARBY MDCRS AIRCRAFT SOUNDINGS AND RADAR VAD WIND PROFILES INDICATED STRONGER WINDS JUST OFF THE DECK...GOING FROM AROUND 15 KTS AT THE SURFACE TO AS HIGH AS 40 TO 50 KTS AROUND 1500 FT AGL. AT THIS TIME...THERE DOES NOT APPEAR TO BE SIGNIFICANT DIRECTIONAL SHEAR OR SHARP VERTICAL SHEAR TO INCLUDE LLWS IN THE TAFS. THE ADVANCING SHOWERS AND ISOLATED THUNDERSTORMS WILL LIKELY RESULT IN A SEVERAL HOUR WINDOW OF MVFR CONDITIONS THU MORNING... AND WILL CONTINUE TO KEEP CIGS HIGHER THAN WHAT THE TOO MOIST MODEL GUIDANCE DEPICTS. SHOWERS ARE EXPECTED TO CLEAR ALL SITES BY LATE MORNING WITH WINDS VEERING TO THE NORTHWEST AND CONDITIONS BECOMING VFR...WHICH WILL DOMINATE THROUGH THE REST OF THE DAY. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...RP KINNEY SHORT TERM...RP KINNEY LONG TERM...GIBBS AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1210 AM CDT THU APR 2 2015 .AVIATION... SOUTHERLY WINDS FROM 5-15 KTS. CLIMB WINDS ARE BRISK WITH LOW LEVEL WIND FLOW IS PICKING UP A BIT SINCE SUNSET WITH DEEP SW FLOW 25-50KTS. AN UPPER LEVEL DISTURBANCE IS TRACKING ACROSS THE ARKLATEX ATTM AND COULD BRING SOME ADDITIONAL ISOLD SHWRS WITH LEFT OVER OUTFLOWS. WE WILL AMEND FOR ANY SUCH WITH FURTHER DIMINISHING CHANCES OVERNIGHT AS LOW CLOUDS AND SOME PATCHY FOG LINGERING INTO MID MORNING. OUTLOOK IS FOR LATE DAY FRIDAY FROPA. && .PREV DISCUSSION... /ISSUED 959 PM CDT WED APR 1 2015/ DISCUSSION... SCT CONVECTION HAS FINALLY BEGUN TO DIMINISH ACROSS THE REGION AS OF MID-EVENING...AS INSTABILITY HAS DIMINISHED SINCE THE SETTING SUN. THE EVENING WATER VAPOR IMAGERY INDICATES THE TAIL END OF A SHORTWAVE TROUGH EXTENDING FROM NW AR INTO SE OK/ECNTRL TX...AND SHOULD CONTINUE TO SHIFT E ACROSS THE REGION OVERNIGHT...EXITING THE AREA STAGE RIGHT SHORTLY AFTER 12Z THURSDAY. WHILE THE 00Z NAM HAS HANDLED THE ONGOING AREA OF -SHRA POORLY...THE LATEST HRRR HAS NOT...AND MAINTAINS THESE -SHRA OVER DEEP E TX/LOWER TOLEDO BEND COUNTRY LATE THIS EVENING...AND WITH ADDITIONAL REDEVELOPMENT POSSIBLE OVER NCNTRL LA AS LARGE SCALE FORCING SPREADS E WITH THE TROUGH. HOWEVER...THIS AREA IS WORKED OVER FROM THE LATE AFTERNOON/EARLY EVENING CONVECTION...THUS THE POTENTIAL FOR DEEP CONVECTION APPEARS TO HAVE GREATLY DIMINISHED. A 30-40KT SWRLY LLJ IS PROGGED TO DEVELOP LATE...WHICH SHOULD RESULT IN THE RAPID INCREASE IN LOW STRATUS LATE. THIS SHOULD LIFT BY MIDDAY THURSDAY...WITH SOME OF THE STRONGER WINDS MIXING DOWN RESULTING IN GUSTY SRLY WINDS OVER AT LEAST THE WRN HALF OF THE AREA. WILL ALLOW THE MID SHIFT TO ANALYZE THE ENTIRE SUITE OF 00Z DATA TONIGHT...WITH A LAKE WIND ADVISORY POSSIBLE THURSDAY. HAVE UPDATED THE ZONES TO ADJUST POPS PER CURRENT RADAR TRENDS...MAINLY TO INCREASE POPS TO CHANCE ACROSS DEEP E TX/NCNTRL LA. DID LOWER POPS TO SLIGHT CHANCE AREAWIDE THURSDAY...AS THE TROUGH/STRONGEST FORCING WILL REMAIN E OF THE AREA. MADE ONLY MINIMAL CHANGES TO MIN TEMPS...AS WINDS/CLOUD COVER WILL KEEP TEMPS IN THE MID/UPPER 60S. ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY. 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 66 81 68 80 / 30 20 10 40 MLU 64 83 66 81 / 30 20 10 50 DEQ 63 78 64 74 / 20 20 30 40 TXK 65 80 66 77 / 30 20 20 40 ELD 64 82 66 79 / 30 20 10 40 TYR 66 82 68 78 / 30 20 10 40 GGG 67 82 68 79 / 30 20 10 40 LFK 67 84 69 80 / 40 20 10 50 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 24/15/05
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
358 AM EDT THU APR 2 2015 LATEST UPDATE... MARINE .SYNOPSIS... ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS EXPECTED TODAY WITH PERHAPS SOME RUMBLES OF THUNDER. MODERATE TO BRIEF HEAVY RAINFALL...ALONG WITH GUSTY WINDS CANNOT BE RULED OUT INTO THE AFTERNOON AS A COLD FRONT SWEEPS THROUGH THE REGION...BUT SEVERE WEATHER IS NOT EXPECTED. MUCH COOLER WEATHER MOVES IN TONIGHT INTO THE WEEKEND...AND ACTIVE WEATHER IS EXPECTED TO CONTINUE. RAIN CHANCES RETURN FRIDAY AFTERNOON ACROSS SOUTHERN LOWER MICHIGAN WITH A CHANCE FOR A RAIN/SNOW MIX FRIDAY NIGHT. FREQUENT BOUTS OF PRECIPITATION ARE EXPECTED SUNDAY INTO THE MIDDLE OF NEXT WEEK. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS WITH PERHAPS A RUMBLE OF THUNDER TODAY FOLLOWED BY MUCH COOLER WEATHER FRIDAY AND SATURDAY. A DRY VERTICAL PROFILE IS NOTED ON A 05Z RAP SOUNDING...BUT HEALTHY MID LEVEL MOISTURE ADVECTION WILL OCCUR FROM THIS WRITING THROUGH THE NEXT SEVERAL HOURS. H925 TO H850 LAYER WAA IS ALSO ONGOING DURING THIS TIMEFRAME WITH STRONG SOUTHWESTERLY FLOW AHEAD OF THE H850 THERMAL TROUGH. AT THE LOW LEVELS...MUCH HIGHER THETA E AIR ADVECTS IN AFTER 12Z THIS MORNING JUST AHEAD OF THE SURFACE COLD FRONT. DEWPOINTS IN THE LOWER 50S ARE EXPECTED THIS AFTERNOON ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. A WEAK SHORTWAVE NOTED OVER WESTERN IL ON WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NORTHEAST INTO OUR AREA BUT LOSE SOME OF ITS PUNCH. NEVERTHELESS...WEAK ELEVATED INSTABILITY IS PRESENT AT THE TIME OF ITS ARRIVAL AROUND 12Z. RAIN CHANCES...WITH PERHAPS A RUMBLE OF THUNDER...INCREASE AFTER 11Z. THE COLD FRONT TRACKS THROUGH THE CWA BETWEEN 16-22Z. DIURNAL HEATING JUST PRIOR TO THIS FRONTAL PASSAGE WILL GIVE MOST AREAS THEIR BEST CHANCE FOR THUNDER AND ASSOCIATED NON-SEVERE THREATS...SUCH AS MODERATE TO BRIEF HEAVY RAIN...GUSTY WINDS...AND LIGHTNING. INSTABILITY IS MARGINAL AT BEST...BUT HIGHEST SOUTH OF I-96. 0-6 KM BULK SHEAR INCREASES THROUGHOUT THE DAY...WITH VALUES OF AROUND 35-45 KNOTS SOUTH OF I-96 AT 18Z. BOTTOM LINE...RAIN SHOWERS WITH A CHANCE OF THUNDER INTO THE AFTERNOON. BEHIND THE FRONT...DRY WEATHER EXPECTED TONIGHT WITH LOWS IN THE 30S TO AROUND 40 DEGREES. ANOTHER PV ANOMALY AND SHORTWAVE MOVE INTO THE AREA TOMORROW...SUPPORTING MAINLY A CHANCE OF RAIN ACROSS THE SOUTHERN FORECAST AREA FRIDAY AFTERNOON AND A MIX OF RAIN AND SNOW FRIDAY NIGHT. LOWER MI IS IN A FAVORABLE POSITION WITHIN A COUPLED UPPER JET STRUCTURE DURING THIS TIMEFRAME...MEANING GOOD UPPER DIVERGENCE IS RESPONSIBLE FOR STRENGTHENING OF THE MIDLEVEL SHORTWAVE. LOWS FRIDAY NIGHT ARE EXPECTED TO PLUMMET INTO THE UPPER TEENS AND 20S. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM EDT THU APR 2 2015 LOOKS LIKE AN ACTIVE STORM TRACK SETTING UP IN THE EXTENDED PERIOD WITH FREQUENT BOUTS OF PRECIPITATION...INCLUDING SOME SNOW AT TIMES. A PLAINS LOW MOVES EAST TOWARDS THE GREAT LAKES SATURDAY NIGHT AND ISENTROPIC ASCENT OUT AHEAD OF IT SHOULD RESULT IN SOME LIGHT SNOW AND RAIN SATURDAY NIGHT. IT TAKES UNTIL MONDAY AFTERNOON BEFORE THE COLD AIR HAS ERODED ENOUGH TO ALLOW FOR A FORECAST OF ALL RAIN ACROSS THE ENTIRE FORECAST AREA. BEST CHANCE FOR STEADY RAIN WILL BE ON MONDAY NIGHT AS THE SFC WAVE TRACKS ALONG THE FRONT DRAPED ACROSS LOWER MICHIGAN. A SECOND WAVE PROLONGS THE PRECIP INTO TUESDAY NIGHT...AND ENOUGH COLD AIR RETURNS TO BRING THE POSSIBILITY OF A MIX ACROSS THE NORTHERN FORECAST AREA BEFORE THE PRECIP TAPERS OFF ON WEDNESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1116 PM EDT WED APR 1 2015 MOISTURE RIDING NORTHEASTWARD AHEAD OF COLD FRONT WHICH IS LOCATED IN MINNESOTA WILL TRACK INTO MICHIGAN LATE TONIGHT AND THURSDAY MORNING. THIS WILL SUPPORT SHOWERS AND THUNDERSTORMS... BEGINNING AROIUND DAYBREAK FOR KMKG. AS THE FRONT TRACKS THROUGH MI DURING THE DAY ON THU...THERE WILL BE ADDITIONAL SHOWERS AND THUNDERSTORMS WITH ASSOCIATED IMPACTS. IFR CONDITIONS LOOK LIKELY TO DEVELOP AS THE WINDS BECOME MORE WESTERLY BEHIND THE FRONT. IT IS NOT CLEAR HOW LONG THE IFR WILL LAST...BUT IMPROVEMENT IS EXPECTED DURING THE EVENING. && .MARINE... ISSUED AT 358 AM EDT THU APR 2 2015 SOUTH WINDS TO 30 KNOTS THIS MORNING WILL VEER SOUTHWESTERLY AT 10 TO 20 KNOTS IN THE AFTERNOON. 3 TO 5 FOOT WAVES TODAY WILL SUBSIDE TO 1 TO 2 FEET THIS EVENING. A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH 2 PM FOR THE NEARSHORE WATERS. PERIODS OF RAIN ARE EXPECTED TODAY ALONG WITH A CHANCE FOR THUNDER AS A COLD FRONT SWEEPS THROUGH. THE RAIN WILL MOVE OUT THIS AFTERNOON. SOUTHWEST WINDS AROUND 10 KNOTS WILL VEER WESTERLY TONIGHT. NORTHERLY WINDS AT 10 TO 20 KNOTS ARE EXPECTED ON FRIDAY...RESULTING IN WAVES BUILDING SOMEWHAT. && .HYDROLOGY... ISSUED AT 1120 AM EDT TUE MAR 31 2015 RIVERS CONTINUE TO REMAIN WELL BELOW ADVISORY LEVELS WITH ONLY SMALL AND MOMENTARY RESPONSES NOTED FROM RECENT PRECIPITATION. NORTHERN SECTIONS OF THE FORECAST AREA WILL SEE SLOWER RESPONSES DUE TO SNOW MELT WITH LAST NIGHTS SNOWFALL. WE WILL SEE A RATHER ACTIVE PATTERN SET UP THROUGH THE NEXT 7 DAYS. MUCH OF THIS COMES IN TWO WAVES...ONE THURSDAY THEN THE SECOND VERY LATE IN THE WEEKEND AND INTO THE NEXT WORK WEEK. GENERAL AMOUNTS ON TOTAL PRECIPITATION THROUGH THE PERIOD ARE AROUND ONE INCH OR SO. THIS IS FAIRLY EVENLY DIVIDED BETWEEN THE TWO WAVES WHICH SHOULD BE FAVORABLE FOR RESPONSE TIMES. NO FLOODING IS EXPECTED AT THIS TIME. HOWEVER...THE HEAVIER RAIN THAT IS ANTICIPATED TO OUR SOUTH THROUGH THE OHIO VALLEY SHOULD BE WATCHED IN THE EVENT THAT ANY ADJUSTMENTS ARE NEEDED IN PRECIPITATION AMOUNTS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>849. && $$ SYNOPSIS...EBW SHORT TERM...EBW LONG TERM...OSTUNO AVIATION...MJS HYDROLOGY...JAM MARINE...EBW
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
329 AM EDT THU APR 2 2015 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM .SYNOPSIS... ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS EXPECTED TODAY WITH PERHAPS SOME RUMBLES OF THUNDER. MODERATE TO BRIEF HEAVY RAINFALL...ALONG WITH GUSTY WINDS CANNOT BE RULED OUT INTO THE AFTERNOON AS A COLD FRONT SWEEPS THROUGH THE REGION...BUT SEVERE WEATHER IS NOT EXPECTED. MUCH COOLER WEATHER MOVES IN TONIGHT INTO THE WEEKEND...AND ACTIVE WEATHER IS EXPECTED TO CONTINUE. RAIN CHANCES RETURN FRIDAY AFTERNOON ACROSS SOUTHERN LOWER MICHIGAN WITH A CHANCE FOR A RAIN/SNOW MIX FRIDAY NIGHT. FREQUENT BOUTS OF PRECIPITATION ARE EXPECTED SUNDAY INTO THE MIDDLE OF NEXT WEEK. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS WITH PERHAPS A RUMBLE OF THUNDER TODAY FOLLOWED BY MUCH COOLER WEATHER FRIDAY AND SATURDAY. A DRY VERTICAL PROFILE IS NOTED ON A 05Z RAP SOUNDING...BUT HEALTHY MID LEVEL MOISTURE ADVECTION WILL OCCUR FROM THIS WRITING THROUGH THE NEXT SEVERAL HOURS. H925 TO H850 LAYER WAA IS ALSO ONGOING DURING THIS TIMEFRAME WITH STRONG SOUTHWESTERLY FLOW AHEAD OF THE H850 THERMAL TROUGH. AT THE LOW LEVELS...MUCH HIGHER THETA E AIR ADVECTS IN AFTER 12Z THIS MORNING JUST AHEAD OF THE SURFACE COLD FRONT. DEWPOINTS IN THE LOWER 50S ARE EXPECTED THIS AFTERNOON ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. A WEAK SHORTWAVE NOTED OVER WESTERN IL ON WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NORTHEAST INTO OUR AREA BUT LOSE SOME OF ITS PUNCH. NEVERTHELESS...WEAK ELEVATED INSTABILITY IS PRESENT AT THE TIME OF ITS ARRIVAL AROUND 12Z. RAIN CHANCES...WITH PERHAPS A RUMBLE OF THUNDER...INCREASE AFTER 11Z. THE COLD FRONT TRACKS THROUGH THE CWA BETWEEN 16-22Z. DIURNAL HEATING JUST PRIOR TO THIS FRONTAL PASSAGE WILL GIVE MOST AREAS THEIR BEST CHANCE FOR THUNDER AND ASSOCIATED NON-SEVERE THREATS...SUCH AS MODERATE TO BRIEF HEAVY RAIN...GUSTY WINDS...AND LIGHTNING. INSTABILITY IS MARGINAL AT BEST...BUT HIGHEST SOUTH OF I-96. 0-6 KM BULK SHEAR INCREASES THROUGHOUT THE DAY...WITH VALUES OF AROUND 35-45 KNOTS SOUTH OF I-96 AT 18Z. BOTTOM LINE...RAIN SHOWERS WITH A CHANCE OF THUNDER INTO THE AFTERNOON. BEHIND THE FRONT...DRY WEATHER EXPECTED TONIGHT WITH LOWS IN THE 30S TO AROUND 40 DEGREES. ANOTHER PV ANOMALY AND SHORTWAVE MOVE INTO THE AREA TOMORROW...SUPPORTING MAINLY A CHANCE OF RAIN ACROSS THE SOUTHERN FORECAST AREA FRIDAY AFTERNOON AND A MIX OF RAIN AND SNOW FRIDAY NIGHT. LOWER MI IS IN A FAVORABLE POSITION WITHIN A COUPLED UPPER JET STRUCTURE DURING THIS TIMEFRAME...MEANING GOOD UPPER DIVERGENCE IS RESPONSIBLE FOR STRENGTHENING OF THE MIDLEVEL SHORTWAVE. LOWS FRIDAY NIGHT ARE EXPECTED TO PLUMMET INTO THE UPPER TEENS AND 20S. && .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM EDT THU APR 2 2015 LOOKS LIKE AN ACTIVE STORM TRACK SETTING UP IN THE EXTENDED PERIOD WITH FREQUENT BOUTS OF PRECIPITATION...INCLUDING SOME SNOW AT TIMES. A PLAINS LOW MOVES EAST TOWARDS THE GREAT LAKES SATURDAY NIGHT AND ISENTROPIC ASCENT OUT AHEAD OF IT SHOULD RESULT IN SOME LIGHT SNOW AND RAIN SATURDAY NIGHT. IT TAKES UNTIL MONDAY AFTERNOON BEFORE THE COLD AIR HAS ERODED ENOUGH TO ALLOW FOR A FORECAST OF ALL RAIN ACROSS THE ENTIRE FORECAST AREA. BEST CHANCE FOR STEADY RAIN WILL BE ON MONDAY NIGHT AS THE SFC WAVE TRACKS ALONG THE FRONT DRAPED ACROSS LOWER MICHIGAN. A SECOND WAVE PROLONGS THE PRECIP INTO TUESDAY NIGHT...AND ENOUGH COLD AIR RETURNS TO BRING THE POSSIBILITY OF A MIX ACROSS THE NORTHERN FORECAST AREA BEFORE THE PRECIP TAPERS OFF ON WEDNESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1116 PM EDT WED APR 1 2015 MOISTURE RIDING NORTHEASTWARD AHEAD OF COLD FRONT WHICH IS LOCATED IN MINNESOTA WILL TRACK INTO MICHIGAN LATE TONIGHT AND THURSDAY MORNING. THIS WILL SUPPORT SHOWERS AND THUNDERSTORMS... BEGINNING AROIUND DAYBREAK FOR KMKG. AS THE FRONT TRACKS THROUGH MI DURING THE DAY ON THU...THERE WILL BE ADDITIONAL SHOWERS AND THUNDERSTORMS WITH ASSOCIATED IMPACTS. IFR CONDITIONS LOOK LIKELY TO DEVELOP AS THE WINDS BECOME MORE WESTERLY BEHIND THE FRONT. IT IS NOT CLEAR HOW LONG THE IFR WILL LAST...BUT IMPROVEMENT IS EXPECTED DURING THE EVENING. && .MARINE... ISSUED AT 315 PM EDT WED APR 1 2015 SOUTHERLY WINDS WILL INCREASE THROUGH THE EVENING HOURS AHEAD OF AN APPROACHING COLD FRONT. SMALL CRAFT ADVISORY CONDITIONS ARE EXPECT THROUGH THE NIGHT AND MUCH OF THURSDAY. SHOWERS AND A FEW THUNDERSTORMS WILL SWEEP ACROSS THE REGION THURSDAY MORNING AND EARLY AFTERNOON. && .HYDROLOGY... ISSUED AT 1120 AM EDT TUE MAR 31 2015 RIVERS CONTINUE TO REMAIN WELL BELOW ADVISORY LEVELS WITH ONLY SMALL AND MOMENTARY RESPONSES NOTED FROM RECENT PRECIPITATION. NORTHERN SECTIONS OF THE FORECAST AREA WILL SEE SLOWER RESPONSES DUE TO SNOW MELT WITH LAST NIGHTS SNOWFALL. WE WILL SEE A RATHER ACTIVE PATTERN SET UP THROUGH THE NEXT 7 DAYS. MUCH OF THIS COMES IN TWO WAVES...ONE THURSDAY THEN THE SECOND VERY LATE IN THE WEEKEND AND INTO THE NEXT WORK WEEK. GENERAL AMOUNTS ON TOTAL PRECIPITATION THROUGH THE PERIOD ARE AROUND ONE INCH OR SO. THIS IS FAIRLY EVENLY DIVIDED BETWEEN THE TWO WAVES WHICH SHOULD BE FAVORABLE FOR RESPONSE TIMES. NO FLOODING IS EXPECTED AT THIS TIME. HOWEVER...THE HEAVIER RAIN THAT IS ANTICIPATED TO OUR SOUTH THROUGH THE OHIO VALLEY SHOULD BE WATCHED IN THE EVENT THAT ANY ADJUSTMENTS ARE NEEDED IN PRECIPITATION AMOUNTS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>849. && $$ SYNOPSIS...EBW SHORT TERM...EBW LONG TERM...OSTUNO AVIATION...MJS HYDROLOGY...JAM MARINE...MANN
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
125 AM CDT THU APR 2 2015 .UPDATED FOR 06Z AVIATION DISCUSSION... ISSUED AT 116 AM CDT THU APR 2 2015 && .SHORT TERM...(TONIGHT) ISSUED AT 415 PM CDT WED APR 1 2015 THE WARM FRONT HAS LIFTED THROUGH THE FA WITH WIDESPREAD TEMPERATURES IN THE 70S...AND A FEW SPOTS IN SOUTHERN MN IN THE 80S WHERE SKIES HAVE REMAINED MOSTLY CLEAR. NORTH OF ABOUT MANKATO...MID AND HIGH CLOUDS HAVE PERSISTED THROUGH THE DAY...WITH ACCAS DEVELOPING AND A FEW SPOTTY THUNDERSTORMS AS WELL. VERY STRONG WINDS THIS AFTERNOON WILL CONTINUE TO AROUND 00Z AND BEGIN WEAKENING. THE SURFACE LOW IS ADVANCING NNE JUST NORTH OF GRAND FORKS WITH A TRAILING COLD FRONT EXTENDING SSW FROM THERE THROUGH THE EASTERN DAKOTAS. THIS FRONT WILL BE THE FOCUS OF THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON AND THIS EVENING. IN TERMS OF FIRE WEATHER CONCERNS FOR THE REMAINDER OF THE DAY...A TONGUE OF MOISTURE IS PUSHING THROUGH EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...SO RH VALUES ARE GENERALLY BEGINNING TO RISE... AND THIS TREND WILL EXPAND EASTWARD THROUGH THE REMAINDER OF THE AFTERNOON. THE VERY STRONG WINDS ARE EXPECTED TO MOSTLY MAINTAIN THEIR STRENGTH THROUGH AROUND 00Z. WINDS WILL TURN NORTHWESTERLY BEHIND THE FRONT AND BE COMPARATIVELY LIGHT OVERNIGHT...ABOUT 5-10KTS OVERNIGHT. THE COLD FRONT WILL PUSH INTO WESTERN MN LATE THIS AFTERNOON. THE TREND HAS BEEN TO SLOW ITS PROGRESSION DOWN VERY SLIGHTLY AS IT MOVES EAST. THE HRRR HAS BEEN CONSISTENT IN ITS DEVELOPMENT OF A LINE OF THUNDERSTORMS FROM SOUTHWESTERN MN THROUGH ST CLOUD AT ABOUT 23Z...WITH EXPANSION AND PROGRESSION EASTWARD FROM THERE. THE RAP INDICATES A NARROW AREA OF CAPE ALONG AND PARALLEL TO THE COLD FRONT...INCREASING TO ABOUT 1000 J/KG AFTER 00Z FROM NEAR HUTCHINSON TO THE SOUTHWEST AND PUSHING EASTWARD AHEAD OF THE FRONT. THE BEST EFFECTIVE BULK SHEAR WILL BE ACROSS SOUTHERN MN...AND ALIGNS WELL WITH THE SLIGHT RISK AREA. SO...STORMS WILL INITIATE IN THE AFOREMENTIONED AREA AND EVOLVE EASTWARD...CROSSING THE WI STATE LINE AFTER 02Z...AND CLEARING EAU CLAIRE AROUND 09Z. THE BOUNDARY LAYER IS VERY DRY THIS AFTERNOON...AND WHILE MOISTURE WILL INCREASE AHEAD OF THE STORMS...DAMAGING WIND POTENTIAL STILL EXISTS. HAIL WILL ALSO BE A THREAT...AND THE STRONGEST STORMS IN OUR AREA WILL BE ACROSS FAR SOUTHERN MN WHERE THE BETTER SHEAR WILL BE. .LONG TERM...(THURSDAY THROUGH WEDNESDAY) ISSUED AT 415 PM CDT WED APR 1 2015 FIRST OF TWO COLD FRONTS WILL PASS THRU THE REGION EARLY THU MRNG...SWEEPING AWAY ANY LINGERING PRECIP FROM THE AREA. HOWEVER...DEEP DRY AND COOLER AIR WILL INFILTRATE THE REGION OVERNIGHT INTO THU. STRONG W TO NW WINDS WILL BE EFFECTIVE CARRIERS OF THE CAA...WHICH WILL ALLOW MAX TEMPS THU TO BE ABOUT 20 DEGREES COOLER THAN THE LOW 80S READINGS HIT TDA. THERE WILL ALSO BE A TIGHT PRES GRADIENT BETWEEN THE EARLY MRNG CDFNT AND THE REINFORCING CDFNT EXPECTED TO DROP THRU THE REGION LATE THU...SO W WINDS IN THE 20-30 MPH FOR WRN PORTIONS OF THE CWFA AND 15-25 MPH IN ERN PORTIONS CAN BE EXPECTED THU ALONG WITH DRY CONDS. WINDS WILL DIMINISH THU NIGHT INTO FRI AS HIGH PRESSURE ARRIVES INTO THE REGION. THIS WILL MAINTAIN THE COLDER AIR RESIDENT ACRS THE REGION BEHIND THE PAIR OF COLD FRONTS. A CLIPPER-TYPE LOW PRES SYSTEM WILL SLIDE SEWD ACRS THE DAKOTAS INTO SRN MN...BRINGING LIGHT PRECIP AMOUNTS IN THE FORM OF MAINLY RAIN...BUT POSSIBLY SOME OVERNIGHT LIGHT SNOW. A MORE ORGANIZED SYSTEM LOOKS TO IMPACT THE AREA EARLY NEXT WEEK AND WITH SLIGHTLY BETTER MODEL AGREEMENT...HAVE BEEN ABLE TO NUDGE POPS INTO THE 40-50 PERCENT RANGE. THERE LOOKS TO BE SEVERAL UPPER LEVEL DISTURBANCES RIDING ESE WITHIN THE MEAN FLOW ATOP THE PROLONGED LOW PRES TRACK THAT WILL GIVE SEVERAL PERIODS OF PRECIP. BECAUSE THE COLD AIR WILL REMAIN OVER THE AREA...SOME OF THE PRECIP...MAINLY THE NIGHTTIME PERIODS...MAY BE A MIX OF RAIN/SNOW FOR NRN PORTIONS OF THE CWFA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT |116 AM CDT THU APR 2 2015 VFR CONDITIONS THROUGHOUT. HIGH CLOUDS AND WNW WINDS SHOULD PREVENT FOG FROM DEVELOPING TONIGHT. THURSDAY WILL BE BREEZY WITH WNW WIND GUSTS NEAR 30KTS BY LATE MORNING. NO PRECIP IS EXPECTED. KMSP... NO NOTABLE CHANGES FROM GENERAL AVIATION DISCUSSION /OUTLOOK FOR KMSP/ FRI...VFR. WINDS NW 10-15 KTS. SAT...VFR. WINDS WNW 10-15 KTS. SUN...VFR. WINDS ENE AROUND 10 KTS. && .FIRE WEATHER... ISSUED AT 415 PM CDT WED APR 1 2015 STRONG SOUTHERLY WINDS THIS AFTN OF 25-35 MPH WITH GUSTS TO ARND 50 MPH WILL CONTINUE THRU SUNSET...AND THIS IS IN CONJUNCTION WITH RELATIVE HUMIDITY VALUES DROPPING TO AS LOW AS 20-25 PERCENT. WILL CONTINUE THE RED FLAG WARNING AS ADVERTISED THROUGH IS EXPIRATION THIS EVE. A PAIR OF COLD FRONTAL PASSAGES OVER THE NEXT 24-30 HOURS...ONE OVERNIGHT TNGT AND ANOTHER LATE DAY TMRW...WILL SHIFT WINDS TO A MORE WESTERLY DIRECTION AND ALSO BRING IN MUCH DRIER AIR INTO THE REGION. WINDS OVER WRN MN WILL AGAIN HIT THE 20-30 MPH RANGE WITH HIGHER GUSTS WHILE ERN MN REACH 15-25 MPH. THERE IS ALSO HIGH CONFIDENCE ON RH VALUES DROPPING TO AS LOW AS 15-20 PERCENT FOR THU AFTN. AFTER COLLAB WITH MIFC FIRE OFFICIALS AND SURROUNDING OFFICES...HAVE OPTED TO ISSUE A RED FLAG WARNING FOR MUCH OF WEST CENTRAL THRU SOUTH CENTRAL MN...WITH A FIRE WX WATCH TO THE E AND N OF THE RED FLAG WARNING. THE FIRE WX WATCH IS ISSUED DUE TO LESSER CONFIDENCE OF THE WIND SPEED CRITERIA BEING REACHED IN ERN MN. IN ADDITION...AFTER COLLAB WITH WI DNR OFFICIALS...NO FIRE WEATHER HEADLINES WILL BE ISSUED ATTM SO WILL CONTINUE TO HIGHLIGHT THE HAZARD OF WINDS IN THE 10-20 MPH RANGE AND RH VALUES DOWN TO AROUND 25 PERCENT FOR THAT PORTION OF THE COVERAGE AREA. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...FIRE WEATHER WATCH FROM 10 AM CDT THIS MORNING THROUGH THIS EVENING FOR MNZ042>045-050>053-059>063-068>070-076>078-084- 085-093. RED FLAG WARNING FROM 10 AM THIS MORNING TO 7 PM CDT THIS EVENING FOR MNZ047>049-054>058-064>067-073>075-082-083-091- 092. WI...NONE. && $$ SHORT TERM...SPD LONG TERM...JPC AVIATION...JRB FIRE WEATHER...JPC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1119 PM CDT Wed Apr 1 2015 .DISCUSSION... Issued at 427 PM CDT WED APR 1 2015 Tonight - Thursday: In the very near term an area of convection tied to a pesky MCV over southwestern MO is expected to track northeast and graze the far southeast CWA through early evening. Have increased PoPs over this region to account for this. Attention then turns back to the west and northwest and focuses on two areas...the NE/SD cold front and an area of accas from western KS into the TX Panhandle. Per latest RAP analysis and visible satellite imagery the airmass remains capped within the cold fronts baroclinic zone. Low-level moisture taking its time to arrive. Latest NAM/RAP suggest CIN may not be eroded till closer to 00Z. Still expect a line of convection to form this evening with the front sliding east-southeast overnight. This activity expected to reach far northwest MO towards midnight and then continue across northern MO. Second area being watched is the KS accas and 12z NAM defined a h7 shortwave/vorticity max that will move out of CO this evening. Last several runs of the convective allowing HRRR generates an expanding area of elevated convection which tracks east overnight, crossing the KS/MO border after midnight. 18z NAM qpf hints at this convection but delays the arrival till after 09z. Will side towards the HRRR for now. While the severe threat will be greatly muted due to its arrival time and minimal instability some generous qpf is possible over our northern and western counties. The latter due to the southerly low level jet veering overnight and paralleling the cold front which could result in some post frontal training for several hours. Convection likely to exit the CWA quickly from west to east Thursday morning. However, model consensus indicates the front will stall just south of the CWA, close enough that low chance afternoon PoPs necessary across the far southern counties to account for potential late afternoon redevelopment. Thursday night - Friday night: The aforementioned stalled front will likely remain just south of the CWA during this period. However, post frontal stratiform or weak elevated convective rains are likely north of the boundary Thursday night into Friday morning. An upper level trough is progged to shift eastward within a pseudo westerly flow with pieces of energy ejecting ahead of it through the Central Plains. This should allow for some isentropically induced rain to form and affect most of the CWA. The rain chances will end by Friday afternoon with the passage of the trough axis. Temperatures will be on the cool side and hover in the 50s all day. Clearing skies, light winds and cool high pressure will probably send Sat morning lows to freezing or below.....with a good chance for a frost. Saturday - Sunday: Should be a rather benign weekend with weak ridging aloft translating eastward and surface pressure falls across the plains generating a southerly breeze. Should be a very pleasant weekend with above average temperatures. Sunday night - Wednesday: Looks like an unsettled pattern. Southwesterly flow sets up with the passage of the upper ridge allowing for increasing moist warm air advection. Considerable model uncertainty on PoPs and timing of the next cold front. GFS is much faster and brings a cold front through Monday night in response to a fast moving shortwave coming out of the desert southwest on Monday whereas the 12z ECMWF shows no sign of this wave...maybe A poor reflection by 12z Tuesday. In any event, there is the potential for a couple pieces of weak energy to be embedded within the southwesterly flow and give us a chance for some convection. Temperatures are likely to remain above average for the first part of the week. && .AVIATION...(For the 06Z TAFS through 06Z Thursday Night) Issued at 1118 PM CDT WED APR 1 2015 Line of storms approaching far northwest Missouri will weaken a bit once it reaches the KC area by 09Z, and it`s unlikely any terminal would experience damaging hail or winds greater than 40 kts once storms arrive. Improving conditions expected after sunrise with perhaps some lingering MVFR clouds, otherwise quiet flying conditions for Thursday. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...MJ AVIATION...Hawblitzel
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1154 PM CDT WED APR 1 2015 .UPDATE... ISSUED AT 625 PM CDT WED APR 1 2015 SEVERE WATCH 15 WAS ISSUED EARLIER VALID UNTIL 06Z. STORMS ALONG THE COLD FRONT IN NORTHEAST NEBRASKA HAVE PRODUCED UP TO QUARTER SIZE HAIL AND WIND GUSTS UP TO 50 MPH. BELIEVE THIS MAY TRANSITION INTO MORE OF A WIND EVENT AS WE HEAD THROUGH THE EVENING. && .SHORT TERM...(TONIGHT THROUGH SATURDAY) ISSUED AT 241 PM CDT WED APR 1 2015 MAIN FOCUS IS ON THE DEVELOPING SEVERE WEATHER THREAT AS A COLD FRONT MOVES INTO THE REGION THIS AFTERNOON. THE COLD FRONT AT 19Z WAS LOCATED FROM EAST CENTRAL SD THROUGH NORTHWEST KANSAS...WITH SOME MINIMAL DEVELOPING ALONG THE COLD FRONT ACROSS WESTERN THROUGH NORTH CENTRAL NEBRASKA. HRRR MODEL HAS INDICATED CONVECTION MAY DEVELOP ALONG THE FRONT INTO ANTELOPE/KNOX COUNTIES BY 21Z...BUT THIS STILL SEEMS ABOUT 1 HOUR TOO SOON...DEFINITELY PREFERRING THE 12Z HIRES NMM/ARW AND 00Z SPC SSEO MODELS SUGGESTING DEVELOPMENT MAY HOLD OFF UNTIL 22-23Z. MEANWHILE...THE MOISTURE RETURN HAS STRUGGLED IN OUR AREA...FIRST BEING IMPEDED BY OVERNIGHT CONVECTION TO OUR SOUTH...AND NOW SURFACE DEWPOINTS HAVE BEEN MIXING DOWN DESPITE THE STRONG SOUTHERLY WINDS...WHICH AT TIMES HAVE MET WIND ADVISORY CRITERIA ACROSS THE NORTHERN HALF OF THE FORECAST AREA. THE COMBINATION OF TEMPS IN THE LOWER 80S AND STRONG WINDS HAS LED TO VERY HIGH DANGER AS WELL. LOW 50S DEWPOINTS HAVE REACHED NORTHEAST KANSAS AND SOUTHWEST IOWA THOUGH...WE SHOULD SEE DEWPOINTS RECOVER INTO THE 50S THIS EVENING AS TEMPS COOL. BULK WIND SHEAR IS NOT THAT IMPRESSIVE AT 30-35 KNOTS INITIALLY... BUT SHOULD INCREASE TO 40 TO 50 KNOTS THROUGH THE EVENING. LOW LEVEL JET SHOULD ALSO STRENGTHEN WHICH MAY HELP BOOST STORM POTENTIAL THROUGH THE EVENING...ALTHOUGH THE LATER INTO THE EVENING...THEN INSTABILITY BEGINS TO WANE A BIT. FEELING IS THAT STORMS WILL DEVELOP IN NORTHEAST NEBRASKA BY 22-23Z...THEN DEVELOP INTO MORE OF A LINER CLUSTER OF STORMS THAT THEN MOVE ACROSS THE FORECAST AREA THROUGH THE EVENING...AND OUT OF THE AREA BY DAYBREAK THURSDAY. STORMS PROBABLY DON`T REACH LINCOLN UNTIL 8-9 PM AND OMAHA 9-10 PM...AND SOUTHEAST NE AND SOUTHWEST IA EVEN LATER. SOME AREAS COULD GET AROUND AN INCH OF RAIN PLUS OR MINUS...BUT STILL WELL WITHIN 3 HOURLY FLASH FLOOD GUIDANCE VALUES OF JUST OVER 2 INCHES. DRY AND COOLER BUT STILL ABOVE NORMAL WEATHER EXPECTED FOR THURSDAY. ANOTHER WEAK WAVE MOVES OUT OF THE CENTRAL ROCKIES THURSDAY NIGHT WHICH COULD BRING A FEW SHOWERS TO THE SOUTHERN HALF OF THE FORECAST AREA...THEN EVEN COOLER FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. SATURDAY SHOULD BE ANOTHER BEAUTIFUL DAY WITH TEMPS BACK INTO THE MID/UPPER 60S WITH BREEZY CONDITIONS DEVELOPING. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 241 PM CDT WED APR 1 2015 EASTER SUNDAY SHOULD ALSO BE ANOTHER BEAUTIFUL DAY WITH LOTS OF SUNSHINE AND TEMPS IN THE UPPER 60S. AS WEAK SOUTHWEST FLOW ALOFT REDEVELOPS LATE IN THE WEEKEND THROUGH EARLY NEXT WEEK...THERE COULD BE ISOLATED CHANCES FOR SHOWERS/STORMS SUNDAY NIGHT THROUGH ABOUT TUESDAY...ALTHOUGH THERE ARE SOME MODEL DISCREPANCIES BETWEEN GFS/ECMWF AND THUS CONFIDENCE IS LOW ON THE DETAILS AT THIS TIME. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1151 PM CDT WED APR 1 2015 THUNDERSTORMS HAVE CLEARED KOFK WITH LINGERING SHOWERS IN THE VICINITY THERE FOR AN HOUR OUR TWO. THUNDERSTORMS COULD OCCASIONALLY OCCUR AT KLNK/KOMA THROUGH ABOUT 08Z...THEN SHOWERS THROUGH ABOUT 11Z. SEVERE THREAT IS OVER FOR THE TAF SITES. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...DEWALD SHORT TERM...DEWALD LONG TERM...DEWALD AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1255 AM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE WILL MOVE OFFSHORE THURSDAY LEADING TO ABOVE NORMAL TEMPERATURES THROUGH LATE WEEK. A COLD FRONT WILL CROSS EARLY SATURDAY BRINGING A CHANCE FOR SHOWERS. DRY HIGH PRESSURE WILL SETTLE BACK ACROSS THE AREA SUNDAY AND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 115 AM THURSDAY...SURFACE HIGH PRESSURE OVER THE OUTER BANKS IS BEGINNING TO PUSH EAST AND OFF THE COAST. BESIDES DIURNAL EFFECTS WHICH TYPICALLY LEAD TO SUBSIDING SURFACE WINDS...THERE ARE NO SYNOPTIC EFFECTS THAT WOULD LEAD ME TO BELIEVE WINDS WOULD DECREASE. LATEST HRRR MODEL SHOWS A FEW HOURS (09Z-11Z) OF WEAK WIND SPEEDS JUST BEFORE DAYBREAK AND I`LL TREND THE FORECAST IN THAT DIRECTION. THIS REQUIRES AN UPWARD ADJUSTMENT TO LOW TEMPERATURES BY A COUPLE DEGREES IN MOST AREAS. OTHERWISE CLEAR SKIES CONTINUE. DISCUSSION FROM 1000 PM FOLLOWS... COOL AND DRY HIGH PRESSURE CONTINUES TO BUILD STRONGLY SOUTHWARD ACROSS THE EASTERN CAROLINAS. MODEL SOUNDINGS SHOW A DRY COLUMN WITH P/W VALUES AROUND A THIRD OF AN INCH...SO EXPECT A CLEAR AND DRY OVERNIGHT PERIOD. HIGHER CLOUDS TO OUR W AND NW ARE EXPECTED TO LARGELY ERODE AS THEY MOVE INTO AN AREA OF STRONG SUBSIDENCE OVERNIGHT. GOOD RADIATIONAL COOLING CONDITIONS WILL LEAD TO OVERNIGHT LOWS RANGING FROM THE UPPER 30S ACROSS OUR NORTHERNMOST ZONES TO LOWER 50S ACROSS SOUTHERNMOST AREAS. LOWS ACROSS MOST LOCATIONS WILL BE IN THE LOWER TO MID 40S. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... AS OF 300 PM WEDNESDAY...A WESTERLY FLOW ALOFT WILL PREVAIL THROUGH THE PERIOD WITH SOME MINOR PERTURBATIONS. A WEAKENING SHORTWAVE WILL MOVE ACROSS THE REGION THURSDAY AFTERNOON ON THE HEELS OF A WEAK RIDGE. ANY QPF ASSOCIATED WITH THIS FEATURE SHOULD DISSIPATE BEFORE ENTERING OUR CWA. BEYOND THIS...A BROAD SOUTHWEST FLOW FROM BERMUDA HIGH PRESSURE WILL BE THE MAIN WEATHER MAKER. THIS LEADS TO WARM TEMPERATURES...HIGHS IN THE LOW TO MIDDLE 70S THURSDAY WITH AN ADDITIONAL FIVE TO EIGHT DEGREES TACKED ON FRIDAY. OVERNIGHT LOWS WILL CONTINUE TO BE BALMY WITH UPPER 50S TO LOWER 60S EXPECTED. A FRONT APPROACHES LATE IN THE PERIOD AND FOLLOWING GUIDANCE I HAVE DELAYED POPS FOR A FEW HOURS AS IT WILL TAKE SOME TIME FOR THE WEAKENING SYSTEM TO TRAVERSE THE APPALACHIANS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 300 PM WEDNESDAY...SHOWERS EARLY SATURDAY ASSOCIATED WITH A COLD FRONT REPRESENT THE ONLY MEANINGFUL RAIN CHANCES FOR THE ENTIRE LONG TERM. ANY WET WEATHER SHOULD END BY MIDDAY AS THE DEEP MOISTURE IS SHUNTED OFF THE COAST THEREAFTER. CLOUD COVER WILL SIMILARLY MAKE A QUICK EXIT THANKS TO LOW AMPLITUDE IN THE MID LEVEL FLOW PROMOTING DEEP LAYER DRYING. FOLLOWING THE FROPA SATURDAY NIGHT AND SUNDAY WILL BE A BIT COOLER THAN CLIMO BUT RETURN FLOW KICKING IN BY SUNDAY NIGHT WILL BRING BACK SEASONABLE TEMPS, ANY WARM ADVECTION AIDED AT NIGHT BY AN INCREASE IN CLOUD COVER. WITH THE CONTINUATION OF SOUTHWESTERLY LOW LEVEL FLOW MODEL GUIDANCE AS USUAL STARTS TO DEPICT STRAY SHOWER ACTIVITY. HOWEVER WITH THE MID LEVELS REMAINING DRY THIS SEEMS RATHER UNLIKELY AND POPS WILL BE CAPPED AT 20 PERCENT. EVEN THE APPROACH OF A COLD FRONT ON WEDNESDAY MAY NOT RAMP UP RAIN CHANCES APPRECIABLY AS WE REMAIN ON THE NORTHERN PERIPHERY OF AN UPPER RIDGE SPANNING THE GULF AND BAHAMAS. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 06Z...HIGH CONFIDENCE FOR VFR THROUGH THE VALID TAF PERIOD AS HIGH PRESSURE REMAINS IN CONTROL ACROSS THE AREA. VFR WILL CONTINUE ACROSS THE AREA THROUGH THE OVERNIGHT HOURS AS NEARLY CLEAR SKIES PREVAIL AND EAST-SOUTHEASTERLY WINDS BECOME AOB 5 KTS. GIVEN FAIRLY DRY ATMOSPHERIC COLUMN...DO NOT ANTICIPATE ANY FOG DEVELOPMENT THOUGH COULD NOT RULE OUT PATCHY GROUND FOG. AFTER DAYBREAK...VFR WILL PREVAIL WITH LIGHT EAST-SOUTHEASTERLY WINDS...INCREASING TO AOB 12 KTS WITH GUSTS UP TO 20 KTS POSSIBLE. INTO THE LATE AFTERNOON HOURS...GUSTS WILL SUBSIDE AND WILL SEE HIGH CLOUDS GRADUALLY INFILTRATE INTO THE AREA AHEAD OF THE NEXT APPROACHING WEATHER SYSTEM...BECOMING SCT/BKN INTO THE EVENING HOURS WITH FEW/SCT LOW CLOUDS AS WELL. EXTENDED OUTLOOK...SLIGHT CHANCE SHOWERS FRIDAY WITH A BETTER CHANCE SHOWERS/MVFR FRIDAY NIGHT INTO EARLY SATURDAY. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 115 AM THURSDAY...THE ONLY SIGNIFICANT CHANGE WAS TO INCREASE NEARSHORE SEA HEIGHTS BY A COUPLE OF FEET GIVEN THE SOLIDLY ONSHORE FLOW ALONG THE COAST. WINDS OUT AT THE FRYING PAN SHOALS BUOY ARE GUSTING TO 25 KTS WITH SEAS OVER 6 FEET. CONDITIONS SHOULD BEGIN TO SLOWLY IMPROVE IN A COUPLE OF HOURS. DISCUSSION FROM 1000 PM FOLLOWS... WINDS AND SEAS ARE EXPECTED TO TREND LOWER THROUGH THE NIGHT. NE WINDS 15 TO 20 KT WILL DIMINISH TO 10 TO 15 KT. THE WIND DIRECTION WILL BE ENE. SEAS OF 3 TO 4 FT THIS EVE WITH SOME 5 FT SEAS ACROSS THE OUTER FRINGES WILL SUBSIDE TO 2 TO 4 FT TOWARD MORNING. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 PM WEDNESDAY...THE COASTAL WATERS WILL BE DOMINATED BY A RETURN FLOW AFTER A FEW HOURS OF LINGERING EASTERLY WINDS EARLY THURSDAY. BY MIDDAY...A SOUTHEASTERLY DIRECTION WILL BE IN PLACE. THE DIRECTION WILL SLOWLY VEER TO SOUTH AND EVENTUALLY SOUTHWEST BY FRIDAY AFTERNOON. SPEEDS WILL PICK UP DURING THIS TIME FRAME AS WELL INCREASING FROM AROUND TEN KNOTS TO 15-20 KNOTS. SEAS WILL INCREASE FROM AROUND TWO FEET THURSDAY TO 4-6 FEET LATE FRIDAY EVENING WITH THE INCREASE IN WINDS. LONG TERM /SATURDAY THROUGH MONDAY/... AS OF 300 PM WEDNESDAY...THE LONG TERM STARTS OFF WITH AGITATED WINDS AND SEAS FOLLOWING THE PASSAGE OF A SATURDAY MORNING COLD FRONT. SMALL CRAFT ADVISORY IS ANTICIPATED THROUGH AT LEAST MID DAY BUT THE AFTERNOON SHOULD SEE AN ABATING TREND IN BOTH. THINGS REALLY COLLAPSE BY SUNDAY WITH HIGH PRESSURE MOVING RIGHT OVERHEAD. THEN A SOUTHERLY COMPONENT SLATED FOR MONDAY AS THE HIGH PROGRESSES OFFSHORE. THE MORE ONSHORE COMPONENT MAY ADD A FOOT IN PREDOMINANT WAVE HEIGHT ALONG THE OUTER REACHES OF THE 20NM FORECAST ZONES. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...RJD/TRA SHORT TERM...SHK LONG TERM...MBB AVIATION...SGL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1129 PM CDT WED APR 1 2015 .UPDATE... ISSUED AT 1129 PM CDT WED APR 1 2015 LOWERED OVERNIGHT TEMPERATURES A FEW DEGREES. WITH A VERY DRY GROUND AND ATMOSPHERE...RADIATIONAL COOLING CAN MAXIMIZE AND TEMPERATURES DROP FAST. UPDATE ISSUED AT 945 PM CDT WED APR 1 2015 HAVE CANCELLED THE RED FLAG WARNING THAT WAS IN EFFECT UNTIL 10 PM CENTRAL THIS EVENING. A FIRE WEATHER WATCH REMAINS IN EFFECT FOR THURSDAY MORNING THROUGH THURSDAY EVENING FOR PORTIONS OF SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA. WINDS HAVE DIMINISHED THIS EVENING WITH SKIES BECOMING CLEAR TO PARTLY CLOUDY. THERE ARE A FEW MID CLOUDS AND POSSIBLY A SPRINKLE OR TWO ALONG THE INTERNATIONAL BORDER TRACKING FROM NORTHWEST INTO NORTH CENTRAL NORTH DAKOTA. NOT SIGNIFICANT ENOUGH TO ADD A MENTION OF SHOWERS. THE NEXT CHANCE OF RAIN OR SNOW WILL BE LATE TONIGHT INTO THURSDAY AS WRAP AROUND MOISTURE ASSOCIATED WITH A SYSTEM IN SOUTHERN CANADA DROPS SOUTH INTO WESTERN AND CENTRAL NORTH DAKOTA. WINDS WILL ALSO INCREASE AGAIN BEGINNING LATE TONIGHT ACROSS THE NORTH AND ACROSS THE ENTIRE FORECAST AREA ON THURSDAY. STRONGEST WINDS ALOFT ARE EXPECTED TO BE DURING THE MORNING HOURS ON THURSDAY...WITH BETTER MIXING IN THE AFTERNOON BUT WINDS ALOFT WILL BE DIMINISHING. WILL NEED TO MONITOR FOR POSSIBLE WIND HIGHLIGHTS. UPDATE ISSUED AT 822 PM CDT WED APR 1 2015 QUICK UPDATED TO EXPIRE THE WIND ADVISORY. WINDS HAVE DIMINISHED SUBSTANTIALLY DURING THE PAST HOUR. ADVISORY WINDS ARE NO LONGER ANTICIPATED THIS EVENING. UPDATE ISSUED AT 643 PM CDT WED APR 1 2015 STRONG WEST TO NORTHWEST WINDS ARE EXPECTED TO DIMINISH BELOW ADVISORY CRITERIA OVER THE NEXT HOUR OR TWO AS WE LOSE OUR DAYTIME HEATING. WILL STILL BE BREEZY THIS EVENING WITH WINDS PICKING UP AGAIN ACROSS THE NORTH LATER TONIGHT...AND ANOTHER WINDY DAY EXPECTED ON THURSDAY. MADE SOME MINOR ADJUSTMENTS TO SKY COVER. ALSO ADJUSTED DEW POINTS LOWER OVER THE SOUTHWEST USED A COMBINATION OF CURRENT FORECAST WITH THE LATEST RAP SURFACE DEW POINTS. THIS IS STILL GIVING SUB 20 PERCENT RH VALUES OVER THE FAR SOUTHWEST. IN ADDITION...WITH SURFACE WINDS STILL STRONG OVER THE FORECAST AREA WILL CONTINUE THE RED FLAG WARNING FOR NOW...WHICH EXPIRES AT 10 PM CENTRAL. WILL TAKE A LOOK AT WINDS OVER THE NEXT HOUR TO SEE IF WE CAN LET THE WIND ADVISORY EXPIRE AT 8 PM. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 346 PM CDT WED APR 1 2015 CURRENT SURFACE ANALYSIS PLACES COLD FRONT PUSHING THROUGH THE RED RIVER VALLEY WITH GUSTY WINDS OVER WESTERN THROUGH CENTRAL NORTH DAKOTA IN ITS WAKE. UPPER LEVEL ANALYSIS PLACES LOW ROTATING NEAR THE ALBERTA/SASKATCHEWAN BORDER WITH SOUTHWESTERLY FLOW OVER OUR AREA. FOR TONIGHT...WINDS WILL DIMINISH A BIT OVERNIGHT THOUGH STILL WILL REMAIN A BIT GUSTY AS PRESSURE GRADIENT REMAINS A BIT TIGHT. OTHERWISE...MAINLY QUIET WEATHER EXPECTED UNTIL TOWARDS MORNING WHEN SHORT WAVE SWINGING AROUND EASTERLY MOVING UPPER LOW NUDGES INTO THE AREA BRINGING LOW PRECIPITATION CHANCES TO THE NORTHWEST. ON THURSDAY...WAVE CONTINUES TO PUSH THROUGH THE AREA BRINGING PRECIPITATION CHANCES OVER THE NORTHERN AND CENTRAL PORTIONS OF THE AREA. THE MAIN CONCERN WITH THIS WILL BE INCREASING WINDS WITH THE NEXT ROUND OF COLD AIR ADVECTION WITH THE SYSTEM. WILL HAVE TO RE-EVALUATE ON LATER SHIFTS TO SEE IF ANOTHER ROUND OF WIND HEADLINES ARE NEEDED. RELATIVE HUMIDITY LEVELS WILL AGAIN BE ON THE LOW SIDE OVER THE SOUTH WHICH WILL COMBINE WITH THE WINDS TO BRING ANOTHER DAY OF FIRE CONCERNS (PLEASE SEE FIRE WEATHER DISCUSSION BELOW). .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 346 PM CDT WED APR 1 2015 AS AN UPPER LOW CONTINUES TO VACATE THE REGION...WINDS WILL BEGIN TO RELAX ON THURSDAY EVENING INTO THE OVERNIGHT HOURS. TEMPERATURES WILL REMAIN NEAR NORMAL FOR THIS TIME OF YEAR...WITH A SLIGHT WARM UP ON FRIDAY AND SATURDAY BEFORE A COOLING TREND BEGINS ON SUNDAY. THE EXTENDED RANGE FEATURES NUMEROUS EMBEDDED IMPULSES WITHIN A FAIRLY ZONAL PATTERN...AND LIGHT PRECIPITATION CHANCES WILL BE POSSIBLE FRIDAY THROUGH SUNDAY. THE GFS AND ECMWF ARE HINTING AT A MORE SIGNIFICANT STORM IN THE MONDAY AND TUESDAY TIME FRAME...BUT QUITE A BIT OF UNCERTAINTY REMAINS AS FAR AS PRECIPITATION TYPE...TIMING...TRACK...AND INTENSITY. WILL HAVE TO KEEP AN EYE ON MODEL TRENDS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1129 PM CDT WED APR 1 2015 MVFR CIGS AND SCATTERED RAIN SHOWERS POSSIBLE AT KISN/KMOT LATER THIS MORNING. OTHERWISE LOW VFR CIGS AND GUSTY WEST WINDS ARE EXPECTED AT ALL TAF SITES. && .FIRE WEATHER... ISSUED AT 346 PM CDT WED APR 1 2015 GUSTY WESTERLY WINDS WILL CONTINUE TO BRING CRITICAL FIRE WEATHER CONDITIONS ACROSS WESTERN AND CENTRAL NORTH DAKOTA INTO THIS EVENING. WINDS WILL DIMINISH SLIGHTLY OVERNIGHT...AND WILL INCREASE AGAIN ON THURSDAY. OVER PORTIONS OF SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA THE GUSTY WINDS WILL AGAIN COMBINE WITH RELATIVE HUMIDITY VALUES AS LOW AS 30 PERCENT TO POSSIBLY BRING ANOTHER DAY OF CRITICAL FIRE WEATHER CONDITIONS. A FIRE WEATHER WATCH HAS BEEN POSTED OVER THIS AREA FOR THURSDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FROM 11 AM CDT /10 AM MDT/ THURSDAY THROUGH THURSDAY EVENING FOR NDZ040>046. && $$ UPDATE...AJ SHORT TERM...JJS LONG TERM...ZH AVIATION...AJ FIRE WEATHER...JJS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
335 AM EDT THU APR 2 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO TODAY AND DRAG A WARM FRONT ACROSS OHIO AND THE LOWER GREAT LAKES REGION. A COLD FRONT WILL FOLLOW MOVING THROUGH FROM THE NORTHWEST DURING THE EVENING. THE COLD FRONT WILL STALL ACROSS SOUTHERN OHIO FRIDAY AS LOW PRESSURE MOVES NORTHEAST ALONG THE BOUNDARY. HIGH PRESSURE WILL TRY TO BUILD OVER THE REGION FROM THE SOUTH THIS WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... CLOUDS INCREASING FROM THE WEST AND NORTHWEST OVERNIGHT AHEAD OF APPROACHING SYSTEM HOWEVER CLOUDS AT THIS POINT REMAIN FAIRLY THIN AND ANY PRECIP WELL WEST OF THE AREA. BY 12Z THE HRRR HAS SHOWERS INTO THE WESTERN COUNTIES. SREF ALSO HAD PRECIP NEAR THE AREA AT 12Z WHILE THE NAM PRINTS OUT A SWATH OF CAPE ON OUR WESTERN BORDER. GIVEN THIS WILL BEGIN WITH CHANCE POPS IN THE WEST AT 12Z. BY 15Z DECENT MOISTURE REACHES AS FAR EAST AS CLEVELAND. FURTHER SATURATION OCCURS EAST IN THE AFTERNOON. WILL HAVE POPS INCREASE TO LIKELY IN THE WEST THROUGH THE MID/LATE MORNING WITH CATEGORICAL POPS WEST EARLY AFTERNOON...SWEEPING EAST-SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING. ALSO...WILL HAVE THUNDER BEGIN AT NOON. MAIN CONCERN WILL BE POTENTIAL FOR SEVERE WITH DEEP MOISTURE AND AFTERNOON HEATING COMBINE WITH INCREASING LOW LEVEL SHEAR. AT THIS TIME WESTERN COUNTIES IN A MARGINAL OUTLOOK WITH BEST CHANCES SOUTHWEST OF THE AREA. HIGHS WELL INTO THE 60S WITH 70 NOT OUT OF THE QUESTION. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... TONIGHT BEGINS WITH WHAT WILL LIKELY BE A LINE OF CONVECTION IN OR MOVING INTO WESTERN OHIO WHICH WILL MOVE SLOWLY EAST-SOUTHEAST THROUGH THE NIGHT. WILL HAVE CAT POPS AND WILL CONTINUE WITH THUNDER THROUGH THE EVENING BUT DROP IT FOR THE OVERNIGHT AS INSTABILITY DECREASES. BY FRIDAY MORNING THE FRONT SHOULD BE IN SOUTHERN OHIO WITH A BRIEF PERIOD OF WEAK HIGH PRESSURE AND DRIER AIR BUILDING IN FROM THE NORTH. BY FRIDAY EVENING HOWEVER...MODELS SHOW LOW PRESSURE MOVES ALONG THE FRONT IN SOUTHERN OHIO SPREADING MOISTURE AND INSTABILITY BACK INTO THE AREA FROM THE SOUTH. WILL BEGIN WITH ONLY A SLIGHT CHANCE POPS SOUTH BUT INCREASE TO CHANCE THROUGH THE MORNING. BY AFTERNOON BROUGHT CATEGORICAL POPS BACK TO A LARGE PORTION OF THE AREA. RAIN CONTINUES INTO THE NIGHT AND THE TRICKY BIT IS THAT COLD ADVECTION BEHIND THE LOW WILL LIKELY TURN PRECIP OVER TO SNOW AFTER MIDNIGHT. THIS WILL BE A CLASSIC ISSUE OF HOW LONG WILL SNOW OCCUR BEFORE THE PRECIP ENDS. MODELS HAVE SHOW SOME CONSISTENCY PAST COUPLE NIGHT WITH SNOW AFTER MIDNIGHT WITH A COUPLE INCHES POSSIBLE BY MORNING. THE MOST SHOULD BE IN THE ELEVATED AREAS OF NWRN PA WHERE 4 INCHES COULD FALL. DONT EXPECT WARNING AMOUNTS BUT COULD POSSIBLY END UP NEEDING AN ADVISORY. PRECIP SHOULD END BY 12Z SATURDAY MOST PLACES AND WILL CONTINUE INTO SAT MORNING ONLY FOR NWRN PA AND XTRM NERN OHIO. SAT MID MORNING AND AFTERNOON SHOULD BE DRY AS HIGH PRESSURE BUILDS IN. NEXT CHANCE OF PRECIP COMES LATE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT BACK DOORS INTO THE AREA. NOT A LOT OF FORCING SO WILL HAVE ONLY CHANCE/SLIGHT CHANCE POPS. SUNDAY NIGHT HOWEVER THE GFS IS SHOWING THAT THE GLFMX MOISTURE GETS TAPPED...REACHING INTO THE AFTER AFTER MIDNIGHT SO WILL HAVE CHANCE POPS FOR ALL. CHILLY SATURDAY BEHIND THE FRONT BUT OTHERWISE NEAR TO ABOVE NORMAL TEMPS. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... A WARMER AND WET PATTERN SETTING UP FOR THE EXTENDED. MODELS CONTINUE WITH A NEARLY STATIONARY FRONT ACROSS THE AREA ON MONDAY. THEN LOW PRESSURE SYSTEM MOVES ALONG STATIONARY FRONT TUESDAY. ECMWF TRACK AND TIMING FASTER THAN LATEST GFS. FRONT SAGS SOUTH OF AREA AS A COLD FRONT WEDNESDAY...BUT THEN A SECOND LOW MOVES NE ALONG THE BOUNDARY THURSDAY. AGAIN PRECISE TIMING STILL IN DOUBT SO WILL CONTINUE WITH HIGH CHANCE POPS AFTER TUESDAY. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... WARM FRONT JUST SW OF STL WILL MOVE NE ACROSS THE FORECAST AREA LATE THIS MORNING. WILL SEE SOME SCATTERED SHOWERS WITH THE FRONT BUT HAVE DOUBTS AS TO HOW WIDESPREAD IT WILL BE. COLD FRONT NOW ACROSS WISCONSIN...WILL MOVE ACROSS THE AREA TONIGHT. AHEAD OF THE FRONT SOUTH WINDS WILL INCREASE TO 20 TO 30 KNOTS THIS AFTERNOON. BEHIND THE FRONT UPWARDS OF A HALF INCH OF RAIN POSSIBLE TOMORROW NIGHT WITH IFR CONDITIONS. .OUTLOOK...NON-VFR INTO SATURDAY. NON VFR POSSIBLE SUNDAY MAINLY EXTREME NE OH/NW PA. && .MARINE... WINDS WILL PICK UP FROM THE SOUTH TO SOUTHWEST ACROSS THE LAKE TODAY AS WARM FRONT LIFTS NE ACROSS THE LAKE. WINDS TURN TO THE NORTHWEST TONIGHT AND DIMINISH FAIRLY QUICKLY AS COLD FRONT PUSHES ACROSS THE LAKE. NORTHWEST FLOW INCREASES FRIDAY NIGHT AS LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY. WINDS AGAIN DIMINISH SATURDAY NIGHT INTO SUNDAY AS HIGH PRESSURE MOVES ACROSS THE LAKE. LIGHT AND VARIABLE FLOW IS EXPECTED UNDER THE INFLUENCE OF THE HIGH AND THEN STATIONARY FRONT THROUGH MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...DJB AVIATION...DJB MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
105 AM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE CENTERED OVER THE EASTERN GREAT LAKES WILL CONTINUE TO MOVE EAST OVERNIGHT. AN AREA OF LOW PRESSURE WILL MOVE ACROSS ONTARIO ON THURSDAY. A WARM FRONT FROM THE LOW WILL LIFT NORTH ACROSS THE AREA TOMORROW AND WILL BE FOLLOWED BY A COLD FRONT DURING THE EVENING. THE COLD FRONT WILL BECOME NEARLY STATIONARY NEAR THE OHIO RIVER FRIDAY AS LOW PRESSURE MOVES NORTHEAST ALONG THE BOUNDARY. HIGH PRESSURE WILL TRY TO BUILD OVER THE REGION FROM THE SOUTH THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... THE FIRST FEW WISPS OF CIRRUS ARE STARTING TO MAKE THEIR WAY SW INTO THE CWA. FOR THE TIME BEING THE CIRRUS WILL REMAIN SCATTERED BUT DURING THE SECOND HALF OF THE NIGHT THE CIRRUS DROPPING IN FROM THE WNW AND THE CIRRUS TO THE SW ARE EXPECTED TO MERGE OVER THE AREA. DUE TO COLLABORATION WILL ONLY ALLOW SKY COVER TO RAMP UP TO 30 TO 40% IN THE SE AND EAST. HRRR AND RUC STILL HOLDING OFF PRECIP NEARING THE WEST UNTIL AFTER 12Z SO CONTINUE TO KEEP THE FORECAST DRY THE REST OF TONIGHT. LOWS WILL PROBABLY OCCUR BY 06Z THEN TEMPS MAY START TO DRIFT UP A FEW DEGREES THROUGH 12Z AS MORE HIGH CLOUDS ARRIVE AND WINDS FROM THE SOUTH START TO INCREASE. && .SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/... THURSDAY WILL BE A WARM AND PROBABLY BUSY DAY. SHOWERS WILL SPREAD EAST ACROSS THE WESTERN END OF THE AREA DURING THE MORNING HOURS. AREAS EAST OF I-71 SHOULD REMAIN DRY THROUGH 18Z. MU CAPES GET TO AROUND 500 J/KG IN THE AFTERNOON WITH BULK SHEAR VALUES AROUND 30 KNOTS. STILL EXPECTING A LINE OF SHOWERS WITH EMBEDDED THUNDER TO DEVELOP TO THE WEST OF THE AREA DURING THE AFTERNOON AND THEN MOVE INTO NW OHIO LATE IN THE DAY. MOST AREAS WILL HEAR THUNDER FOR THE FIRST TIME THIS SPRING. WILL NEED HIGH PRECIP CHANCES ALL AREAS BY LATE IN THE DAY AND AGAIN THURSDAY NIGHT. QPF AMOUNTS IN THE HALF INCH TO THREE QUARTERS OF AN INCH RANGE ARE LIKELY. THE SURFACE COLD FRONT RESPONSIBLE FOR THIS PRECIP WILL STALL TO THE SOUTH OF THE AREA ON FRIDAY. ALL OF THE NEW GUIDANCE CONTINUES TO SHOW A WAVE DEVELOPING ALONG THE FRONT. THIS WILL PUSH THE PRECIP BACK NORTH ACROSS THE AREA LATE FRIDAY. SOUTHERN AREAS MAY NEVER GET OUT OF THE PRECIP FRIDAY BUT A DRY PERIOD IS LIKELY NEAR LAKE ERIE. MORE RAIN IS LIKELY FRIDAY NIGHT WITH THE SHOWERS QUICKLY TAPERING OFF FROM WEST TO EAST EARLY SATURDAY. HIGH PRESSURE WILL THEN START TO BUILD IN FROM THE SOUTHWEST. AS FAR AS THE SEVERE WEATHER POTENTIAL GOES FOR TOMORROW. THINK THERE COULD BE A FEW STORMS THAT APPROACH SEVERE LIMITS. HAVE SOME CONCERN THAT THERE WILL BE A LOT OF CLOUDS AROUND TOMORROW WHICH COULD LIMIT THE DESTABILIZATION. THE LATEST OUTLOOK HAS PART OF THE AREA IN THE MARGINAL CATEGORY AND THIS SEEMS REASONABLE. WILL PUT A MENTION IN THE HWO. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... SUNDAY COULD WIND UP BEING A MIXED WEATHER DEPENDING ON WHERE THE STATIONARY FRONTAL BOUNDARY LINGERS. CURRENTLY...THE FRONT IS PROGGED TO BE OVER LAKE ERIE INTO NORTHWEST PENNSYLVANIA BY SUNDAY MORNING. THE FRONT LINGERS OVER THE AREA THROUGH TUESDAY UNTIL A LOW PRESSURE SYSTEM APPROACHES FROM THE WEST. STATIONARY FRONT WILL BECOME A WARM FRONT AND LIFT NORTH OF THE AREA BY TUESDAY MORNING. THIS SHOULD KEEP THE WARM AIR ADVECTION IN THE AREA DURING THE DAY TUESDAY. THE LOW WILL MOVE EAST OF THE AREA TUESDAY NIGHT INTO WEDNESDAY DRAGGING A COLD FRONT ACROSS THE AREA. AIR MASS BEHIND THE FRONT IS NOT EXPECTED TO BE ALL THAT COLD. HIGH PRESSURE WILL QUICKLY BUILD EAST ACROSS THE NORTHERN GREAT LAKES BY THURSDAY. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... WARM FRONT JUST SW OF STL WILL MOVE NE ACROSS THE FORECAST AREA LATE THIS MORNING. WILL SEE SOME SCATTERED SHOWERS WITH THE FRONT BUT HAVE DOUBTS AS TO HOW WIDESPREAD IT WILL BE. COLD FRONT NOW ACROSS WISCONSIN...WILL MOVE ACROSS THE AREA TONIGHT. AHEAD OF THE FRONT SOUTH WINDS WILL INCREASE TO 20 TO 30 KNOTS THIS AFTERNOON. BEHIND THE FRONT UPWARDS OF A HALF INCH OF RAIN POSSIBLE TOMORROW NIGHT WITH IFR CONDITIONS. .OUTLOOK...NON-VFR INTO SATURDAY. NON VFR POSSIBLE SUNDAY MAINLY EXTREME NE OH/NW PA. && .MARINE... WINDS WILL PICK UP FROM THE SOUTH TO SOUTHWEST ACROSS THE LAKE IN THE WARM AIR ADVECTION PATTERN. AS COLD FRONT SLIPS EAST ACROSS THE LAKE THURSDAY NIGHT...WINDS DIMINISH FAIRLY QUICKLY. NORTHWEST FLOW WILL DEVELOP FRIDAY NIGHT AND THEN DIMINISH AGAIN SATURDAY AS HIGH PRESSURE BEGINS TO BUILD INTO THE REGION. GENERALLY LIGHT AND VARIABLE FLOW IS EXPECTED UNDER THE INFLUENCE OF THE HIGH AND THEN STATIONARY FRONT THROUGH MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KUBINA NEAR TERM...KUBINA SHORT TERM...KUBINA LONG TERM...LOMBARDY AVIATION...DJB MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
212 AM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE WILL MOVE EAST OF THE AREA THURSDAY AS MOIST SOUTHERLY FLOW RETURNS. A COLD FRONT WILL PUSH THROUGH NORTHEAST GEORGIA AND THE WESTERN CAROLINAS ON FRIDAY EVENING AHEAD OF DRIER HIGH PRESSURE FOR THE WEEKEND. MOISTURE WILL RETURN FOR THE START OF THE NEXT WORK WEEK AS SOUTHERLY FLOW INCREASES PRECIPITATION CHANCES. && .NEAR TERM /THROUGH TODAY/... AS OF 130 AM...STILL WAITING FOR LOW LEVEL UPSLOPE FLOW TO MOISTEN AND DEVELOP CLOUDINESS NEAR THE BLUE RIDGE. MIGHT HAVE TO START PUTTING OFF THE ONSET OF THE LIGHT PRECIP WITH THE NEXT UPDATE. TEMPS WERE RUNNING A BIT WARMER THAN FCST OVER THE NC PIEDMONT...SO AN ADJUSTMENT WILL BE MADE. PREVIOUS DISCUSSION... AS OF 1035 PM EDT...THE FORECAST REMAINS ON TRACK WITH THE INCOMING 00Z NAM AND THE MOST RECENT RAP RUNS DEPICTING IMPROVING MOIST UPGLIDE IN THE 3000 TO 6000 FT AGL LAYER FROM THE SW DURING THE OVERNIGHT HOURS. THIS SHOULD LEAD TO INCREASING CLOUDS...WITH MIN TEMPS SLIGHTLY WARMER THAN A CONSENSUS OF GUIDANCE. AS THE WEAK UPGLIDE AND SRLY UPSLOPE FLOW IMPROVES TOWARD DAYBREAK...ISOLD TO SCATTERED LIGHT RAIN SHOWERS SHOULD DEVELOP IN THE SRN MTNS AND IMMEDIATELY ADJACENT FOOTHILL LOCATIONS. RETURN FLOW MOISTURE WILL DEEPEN IN PROFILES THROUGH THU...GRADUALLY EXPANDING OVER MOST OF THE AREA. THE HIGHEST PRECIPITATION CHANCES WILL REMAIN FOCUSED ON THE SRLY UPSLOPE AREAS OF THE SRN MTNS AND ADJACENT FOOTHILLS...BUT WITH ISOLATED SHOWER CHANCES EVENTUALLY EXPANDING EASTWARD TO INTERSTATE 77. THE SOLIDIFYING CLOUD DECK SHOULD KEEP MAXES BELOW GUIDANCE THU AFTN...ESPECIALLY IF IN SITU SHALLOW COLD AIR DAMMING DEVELOPS EAST OF THE BLUE RIDGE. IN ADDITION TO THE MOIST UPGLIDE...A PHASING SHORTWAVE MOVING EAST FROM THE PLAINS WILL CROSS THE REGION DURING THE AFTN. HIGHER DEWPOINTS AND SLIGHTLY MORE INSTABILITY IN SRN SECTIONS MAY PERMIT ISOLD TO SCT TSTMS TO CROSS THE SRN TIER DURING THE AFTN HOURS. && .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... AS OF 245 PM EDT WEDNESDAY...SHORT TERM BEGINS WITH SHORTWAVE PUSHING THROUGH THE SOUTHEAST AND GRADUALLY DAMPING INTO THE OVERALL LONGWAVE PATTERN. FINGER OF STABILITY ALONG THE LEE OF THE APPALACHIANS REMAINS IN PLACE AT THE BEGINNING OF THE PERIOD WITH BEST THUNDER CHANCES IN THE SOUTHERN AND SOUTHWEST PORTIONS OF THE FORECAST AREA...DIMINISHING LATE THURSDAY EVENING. NOT ENOUGH DEEP- LAYER SHEAR TO SUPPORT MUCH OF ANYTHING IN THE WAY OF ORGANIZED CONVECTION. EXPECT A BIT OF A BREAK DURING THE DAY ON FRIDAY BEHIND THE SHORTWAVE. HIGHS ON FRIDAY AFTERNOON SHOULD SOAR BACK WELL ABOVE SEASONAL NORMALS IN RESPONSE TO INCREASING LOW-LEVEL WAA AHEAD OF THE NEXT FRONT TO APPROACH FRIDAY NIGHT INTO EARLY SATURDAY. GFS AND ECMWF HAVE COME INTO MUCH BETTER AGREEMENT WITH THE PAST COUPLE OF RUNS AND BESIDES THE POTENTIAL FOR A FEW UPSLOPE SHOWERS EARLY MORNING FRIDAY...THE MAIN AREA OF PRECIPITATION SHOULD BE PUSHING INTO THE MOUNTAINS FRIDAY LATE MORNING INTO EARLY AFTERNOON. BEST AREA OF CONVECTION WILL BE MORE FRIDAY LATE EVENING AND NIGHT WHEN OF COURSE DIURNAL TRENDS WOULD MINIMIZE CAPE POTENTIAL...BUT EVEN THE MORE CONSERVATIVE GFS DOES BRING A BAND OF SBCAPE BETWEEN 100- 300 J/KG INTO THE LOWER APPALACHIANS. THE CONCERN IS THAT THIS INSTABILITY...ALBEIT WEAK...IS COLLOCATED WITH 60+KT 0-6KM SHEAR... AND 30-40KT 0-1KM SHEAR. SHERB VALUES OVERALL REMAIN BELOW 1 BUT SREF SHERB PLUME FORECASTS FOR THE AREA DO SHOW AT LEAST SOME SREF MEMBERS CREEPING ABOVE 1. SPC DAY3 OUTLOOK OVERNIGHT DID INTRODUCE MARGINAL RISK INTO THE MOUNTAINS SO CANNOT RULE OUT AN ISOLATED SEVERE STORM OR TWO AT THIS TIME...WILL HAVE TO MONITOR THE FORECAST EVOLUTION. ONLY OTHER MINOR ISSUE IS THAT DEPENDING ON TIMING OF FALLING TEMPERATURES BEHIND THE FRONT...IT IS POSSIBLE THAT SOME OF THE HIGHEST PEAKS MAY SEE A BRIEF CHANGEOVER TO SNOW EARLY SATURDAY MORNING. CONFIDENCE NOT PARTICULARLY HIGH WITH THIS AND EVEN IF IT WERE TO OCCUR NO ACCUMULATIONS WOULD BE EXPECTED. AFTER THE FRONT PUSHES THROUGH...ALL POPS MOVE OUT OF THE AREA BY 18Z SATURDAY LEAVING THE REST OF THE DAY TO BE PRETTY NICE WITH TEMPERATURES BELOW SEASONAL NORMALS. THE DRY CONDITIONS CONTINUE INTO THE EXTENDED. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 300 PM EDT WEDNESDAY...EXTENDED BEGINS WITH TEMPERATURES BELOW SEASONAL NORMALS AND CLEAR CONDITIONS BEHIND SATURDAY/S FRONT...WITH SURFACE HIGH PRESSURE IN PLACE AND WEAK NORTHWEST FLOW ALOFT... LEADING TO A NICE EASTER SUNDAY. PRECIPITATION SPREADS ACROSS THE MIDSOUTH AND DEEP SOUTH LATE SUNDAY INTO EARLY MONDAY IN RESPONSE TO A WEAK SHORTWAVE AND ISENTROPIC LIFT ON THE WESTERN PERIPHERY OF THE SURFACE HIGH THAT BY THIS POINT HAS PUSHED OFF INTO THE ATLANTIC. STILL SOME QUESTION ABOUT QPF VALUES AS WELL AS HOW WIDESPREAD THE PRECIPITATION WILL BE...WITH GFS A LITTLE MORE ROBUST ON MONDAY THAN THE ECMWF...AND HAVE CONTINUED TREND OF GENERALLY LOW CHANCE POPS ESPECIALLY WEST DURING THE DAY ON MONDAY. LATE IN THE PERIOD...ANOTHER DEEP TROUGH IN THE ROCKIES PUSHES INTO THE PLAINS. WEAK RIDGING ALOFT OVER THE GULF COMBINED WITH THE DEEPENING TROUGH WILL PRODUCE SOUTHWEST FLOW ALOFT ACROSS THE SOUTHEAST BUT AGAIN SIGNIFICANT UNCERTAINTY REMAINS IN EXACTLY WHERE THE SUBTROPICAL JET MIGHT SET UP. GFS WANTS TO KEEP A BAND OF PRECIPITATION ACROSS THE SOUTHEAST WITH THE ASSOCIATED FRONT PUSHING INTO THE MID-ATLANTIC REGION TUESDAY EVENING WHEREAS THE ECMWF HAS THE MOIST FETCH A BIT FARTHER NORTH MORE IN THE OHIO VALLEY...WITH THE FRONT LINGERING ACROSS THE UPPER MIDWEST. WITH THESE DIFFERENCES AND RESULTING FAIRLY LOW CONFIDENCE...HAVE KEPT TREND OF SLIGHT TO LOW CHANCE POPS WITH A BIT OF A DIURNAL TREND IN THUNDER POTENTIAL. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AT KCLT...VFR...FOR THE TIME BEING. MODEL GUIDANCE DEPICTS THE DEVELOPMENT OF LOW CLOUDS DURING THE EARLY MORNING HOURS AS MOIST SE UPSLOPE DEVELOPS AND STRENGTHENS TOWARD DAWN. MOST OF THE LOW CLOUDS WILL BE CLOSER TO THE BETTER MECHANICAL LIFT NEAR THE BLUE RIDGE. OVER THE WRN PIEDMONT...THIS MAY INITIALLY TAKE THE FORM OF A CLOUD DECK AROUND 050 THAT FORMS A CEILING BY MID/LATE MORNING. THE BETTER PLUME OF LOW MOISTURE MOVES EAST LATER IN THE DAY AND MAY ALLOW AN MVFR CEILING TO FORM IN THE MID/LATE AFTERNOON. THIS WAS PUSHED BACK TO 20Z ON THE NEW TAF. WIND SHOULD STAY SE THIS MORNING AND THEN S THIS AFTERNOON. THE MODELS DIFFER ON THE AMOUNT OF PRECIP DEVELOPMENT EAST OVER THE PIEDMONT LATER TODAY. HAVE KEPT PRECIP OUT OF THE TAF FOR NOW UNTIL MORE GUIDANCE FROM THE CONVECTION-ALLOWING MODELS IS SEEN. AFTER SUNSET...THE LAMP GUIDANCE GROWS MORE PESSIMISTIC WITH AN IFR CEILING SPREADING EAST FROM THE BLUE RIDGE. HAVE KEPT THAT OUT FOR NOW FOR BREVITY AND WILL EVALUATE IT FOR THE NEXT TAF ISSUANCE. IT WILL PROBABLY DEPEND ON PRECIP DEVELOPMENT TO FORM THE IFR CEILING. ELSEWHERE...VFR LEVEL STRATOCUMULUS WILL DEVELOP FROM S TO N ACROSS THE MTN AND FOOTHILL TAFS THROUGH THE EARLY MORNING HOURS. MVFR CIGS WILL THEN BECOME INCREASINGLY LIKELY THROUGH THU MORNING AT KAVL AND THE SC SITES AS THE MOIST UPGLIDE DEEPENS. AT THAT POINT...SOME OF THE GUIDANCE...PARTICULARLY THE LAMP...DEVELOPS AN IFR CEILING IN THE UPSLOPE FLOW AREAS NEAR THE BLUE RIDGE AND THEN FANS IT OUT ACROSS THE UPSTATE/NC FOOTHILLS. NOT CONFIDENT ENOUGH TO INCLUDE AN IFR CEILING IN THE NEW TAFS DURING PEAK HEATING WITHOUT A FAVORABLE LOCATION OF SURFACE HIGH PRESSURE FOR COLD AIR DAMMING AND WITHOUT A HIGH PRECIP PROBABILITY. FEEL THAT MVFR IS A BIT MORE LIKELY GIVEN THE WARM APRIL SUN...BUT WILL CONSIDER KEEPING A TEMPO FOR IFR IN LATER AMENDMENTS. CONDITIONS MAY DETERIORATE AS WE LOSE HEATING... PARTICULARLY OVER THE NC FOOTHILLS. STILL A CHANCE FOR A THUNDERSTORM AT KAND AS THE UPPER SHORT WAVE MOVES THRU AND A PROB30 WAS KEPT THERE. OUTLOOK...MOIST SOUTHEAST UPSLOPE FLOW WILL MOVE OFF FRIDAY MORNING WHICH SHOULD ALLOW LOW CLOUD CEILINGS TO SCATTER AND LIFT. CONDITIONS WILL IMPROVE TO VFR BY FRIDAY AFTERNOON. A COLD FRONT WILL AFFECT THE AREA FRIDAY NIGHT INTO EARLY SATURDAY...BRINGING ANOTHER ROUND OF RAIN/POSSIBLE THUNDERSTORMS AND RESTRICTIONS. VFR WILL RETURN FOR THE REST OF THE WEEKEND. CONFIDENCE TABLE... 06-12Z 12-18Z 18-24Z 00-06Z KCLT HIGH 100% HIGH 100% HIGH 83% MED 74% KGSP HIGH 99% HIGH 91% MED 77% MED 78% KAVL HIGH 97% MED 79% MED 66% HIGH 86% KHKY HIGH 100% HIGH 88% HIGH 88% HIGH 88% KGMU HIGH 94% HIGH 90% MED 77% HIGH 81% KAND HIGH 95% HIGH 81% MED 72% HIGH 80% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...RWH NEAR TERM...HG/PM SHORT TERM...TDP LONG TERM...TDP AVIATION...PM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1105 PM CDT WED APR 1 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 405 PM CDT WED APR 1 2015 THE MAIN WEATHER FOCUS FOR TONIGHT WILL BE THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT ALONG AN ADVANCING COLD FRONT. WHILE THE FRONTAL PROGRESSION HAS SLOWED SOME...MOISTURE RETURNS HAVE ALSO BEEN SLOW. DEWPOINTS ARE JUST STARTING TO BUILD INTO THE LOW TO MID 40S...WITH THE 50+ READINGS STILL WELL SOUTH OF THE REGION. AS A RESULT...CAPE VALUES REMAIN FAIRLY MINIMAL...HOWEVER MID LEVEL LAPSE RATES ARE EXPECTED TO INCREASE THROUGH THIS AFTERNOON. SOUNDINGS SHOW A STRONG INVERTED V WITH A LONG AND SKINNY CAPE AND UNIDIRECTIONAL SHEAR. STILL EXPECT THUNDERSTORMS TO DEVELOP ALONG THE FRONT...HOWEVER THE TIMING OF INITIATION IS A BIT LATER THAT PREVIOUS MODEL RUNS. THE BEST WINDOW OF OPPORTUNITY WOULD BE IN THE EARLY EVENING...WITH STORMS QUICKLY DEVELOPING INTO A LINEAR STRUCTURE. THESE STORMS WILL PROGRESS EAST WITH THE FRONT FAIRLY QUICKLY BEFORE EXITING THE FORECAST AREA BY MIDNIGHT. SEVERE STORMS STILL LOOK POSSIBLE...BUT THE MAIN THREAT WILL PRIMARILY BE DAMAGING WINDS. WITH SURFACE WINDS ALREADY AVERAGING 25 TO 35 MPH...IT WILL NOT TAKE MUCH TO GET SEVERE WIND GUSTS TO OCCUR GIVEN THE INVERTED V SOUNDINGS. THE MAIN SEVERE THREAT WILL BE DAMAGING GUSTS TO 65 OR 70 MPH. HAIL SEEMS LIKE MUCH LESS OF A THREAT AND WOULD BE LARGELY SUB SEVERE. FOLLOWED A BLEND OF THE HRRR AND RAP...WHICH HAVE CONSISTENTLY BEEN SHOWING STORMS DEVELOPING ALONG A LINE FROM NEAR SIOUX CITY TO ORANGE CITY TO WINDOM AROUND 6 OR 7 PM AND TRACKING EAST INTO THE EVENING. STILL LOOKS LIKE STORM DEVELOPMENT WILL FIRE JUST OUTSIDE OF THE SIOUX FALLS AREA...SO HAVE KEPT POPS AROUND 20 PERCENT. ALSO LOWERED QPF AMOUNTS QUITE A BIT GIVEN THE DRIER SCENARIO...BUT COULD SEE LOCALLY AROUND A HALF INCH OF RAIN UNDER A THUNDERSTORM. STRONG WINDS AHEAD OF THE FRONT WILL DECREASE A LITTLE AS THE FRONT ARRIVES THEN TURN NORTHWEST AROUND 20 TO 30 MPH. DECIDED TO EXTEND THE WIND ADVISORY A FEW MORE HOURS THIS AFTERNOON BUT SHOULD BE GOOD TO EXPIRE AROUND 6 PM. AS THE EVENING PROGRESSES WINDS WILL BE ON AN OVERALL DOWNWARD TREND. AFTER MIDNIGHT WINDS WILL SETTLE CLOSER TO 5 TO 10 MPH. LOWS TONIGHT WILL RANGE FROM THE UPPER 30S IN THE WEST TO UPPER 40S IN THE SOUTHEAST. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 405 PM CDT WED APR 1 2015 COOLER AND BREEZY ON THURSDAY...WITH HIGHS IN THE 50S AND 60S AND WEST NORTHWEST WINDS INCREASING INTO THE 20 TO 35 MPH RANGE BY AFTERNOON. GIVEN EXPECTED DEEP MIXING DEWPOINTS WILL LIKELY BE LOWER THAN MOST GUIDANCE. THIS IMPACTS FIRE WEATHER AND IS DESCRIBED BELOW. STILL LOOKS LIKE ANY PRECIPITATION FROM THE WAVE CROSSING THE PLAINS WILL STAY TO OUR SOUTH THURSDAY NIGHT...ALTHOUGH WILL LIKELY SEE INCREASING MID AND HIGH CLOUDS BY THURSDAY AFTERNOON. COOLER AIR ADVECTS IN THURSDAY NIGHT INTO FRIDAY...RESULTING IN MORNING LOWS IN THE 20S AND 30S AND DAYTIME HIGHS ONLY IN THE 40S AND 50S. WILL BE A SUNNY DAY AND WINDS WILL BE A BIT LIGHTER THOUGH...MORE IN THE 10 TO 20 MPH RANGE. A BIT OF A TRICKY FORECAST FOR THE WEEKEND WITH REGARDS TO TEMPERATURES. SHOULD REMAIN DRY...BUT WILL LIKELY SEE A DECENT GRADIENT IN TEMPERATURES WITH A BOUNDARY NEARBY. LATEST MODEL TRENDS SUGGEST A SLIGHTLY FURTHER NORTH POSITION OF THE BOUNDARY...ALLOWING FOR WARMER TEMPERATURES IN OUR REGION. SO TRENDED HIGHS IN THAT DIRECTION...WITH MOST LOCATIONS IN THE 50S AND 60S...POSSIBLY SOME LOW 70S ALONG THE MISSOURI RIVER. FORECAST UNCERTAINTY CONTINUES INTO NEXT WEEK AS MODELS STRUGGLE WITH MAGNITUDE AND TIMING OF WAVES EJECTING EAST OUT OF THE LONGWAVE WEST COAST TROUGH. AS OF NOW LOOKS LIKE A SLIGHT CHANCE OF AN ELEVATED SHOWER OR THUNDERSTORM SUNDAY NIGHT ALONG THE ELEVATED WARM FRONT. AS LOW LEVEL MOISTURE INCREASES...COULD ALSO SEE SOME STRATUS AND DRIZZLE. QUESTION THEN BECOMES WHERE THE LOW TRACKS AND HOW FAST IT MOVES EAST. GEM AND GFS ARE IN ONE CAMP MOVING THE SURFACE LOW OVERHEAD MONDAY AND EXITING TO THE EAST MONDAY NIGHT...WITH THE ECMWF KEEPING MORE OF THE ENERGY BACK AND MOVING THE LOW BY ON TUESDAY. SO FOR NOW CAN JUST SAY PRECIPITATION CHANCES INCREASE MONDAY INTO TUESDAY...BUT EXACT TIMING IS UNCERTAIN. TRACK OF THE LOW WILL DETERMINE WHETHER WE SEE A COLD RAIN OR SOME THUNDERSTORMS. CURRENT CONSENSUS LEANS TOWARDS A COOLER RAIN...WITH MAYBE A FEW STORMS ALONG THE MISSOURI RIVER. BUT THIS COULD CHANGE DEPENDING ON THE EXACT TRACK...AND CAN NOT EVEN RULE OUT SOME SNOW MIXING IN...SO WILL NEED TO MONITOR TRENDS. ANOTHER WAVE MAY BRING ANOTHER PRECIPITATION THREAT WEDNESDAY INTO THURSDAY...SO MAIN STORY WILL BE THE MORE ACTIVE PRECIPITATION THREAT NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1103 PM CDT WED APR 1 2015 SHOWERS WILL IMPACT SIOUX CITY FOR THE UPCOMING 1 TO 2 HOURS OTHERWISE LITTLE TO NO AVIATION IMPACTS EXPECTED AT THE LOCAL AIRPORTS. WINDS WILL CONTINUE TO HOWL FROM THE WEST ON THURSDAY...GUSTING AS HIGH AS 30 KNOTS AT TIMES. INCREASING MID- UPR LVL CLOUDS WILL ARRIVE THURSDAY AFTERNOON. && .FIRE WEATHER... ISSUED AT 405 PM CDT WED APR 1 2015 RED FLAG WARNING WILL CONTINUE INTO EARLY THIS EVENING...WITH STRONG SOUTHWESTERLY WINDS AHEAD OF THE FRONT TURNING NORTHWESTERLY BEHIND IT. UPGRADED SOUTHEAST SOUTH DAKOTA AND SOUTHWEST MINNESOTA TO A RED FLAG WARNING FOR THURSDAY. DEEP MIXING WILL ALLOW FOR RH VALUES TO DROP INTO THE 15 TO 25 PERCENT RANGE FROM LATE MORNING THROUGH THE AFTERNOON. NORTHWESTERLY WINDS WILL ALSO INCREASE INTO THE 20 TO 35 MPH RANGE. KEPT NORTHEAST NEBRASKA AND NORTHWEST IOWA OUT FOR NOW. WINDS ARE MORE BORDERLINE THERE...15 TO 30 MPH AND RAINFALL THIS AFTERNOON AND EVENING MAY BE ENOUGH TO LIMIT FIRE THREAT. HOWEVER IF RAIN TONIGHT ENDS UP MORE SCATTERED OR LESS THAN EXPECTED...MIDNIGHT SHIFT WILL NEED TO CONSIDER INCLUDING THEM IN THE RED FLAG WARNING AS WELL. THE LOW RH CONTINUES FRIDAY INTO SATURDAY...15 TO 25 PERCENT...BUT WINDS SHOULD BE LIGHTER. GENERALLY 10 TO 25 MPH ON FRIDAY OUT OF THE NORTHWEST AND 10 TO 20 MPH OUT OF THE SOUTH ON SATURDAY. THIS SHOULD KEEP US BELOW RED FLAG CRITERIA BOTH DAYS...BUT STILL EXPECT HIGH TO VERY HIGH FIRE DANGER GIVEN DRY FUELS AND LOW RH. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...RED FLAG WARNING FROM 11 AM TO 7 PM CDT THURSDAY FOR SDZ255>258. MN...RED FLAG WARNING FROM 11 AM TO 7 PM CDT THURSDAY FOR MNZ900. IA...NONE. NE...NONE. && $$ SHORT TERM... LONG TERM...CHENARD AVIATION...DUX FIRE WEATHER...CHENARD
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
332 AM CDT THU APR 2 2015 .TODAY...FORECAST CONFIDENCE MEDIUM. AWAITING SHOWERS OVER NE IOWA IN REGION OF MOISTURE CONVERGENCE ALONG SURFACE TROUGH AND STRONGER 700 MB OMEGA AHEAD OF MID-LEVEL TROUGH AXIS THAT WILL ACCOMPANY LEAD VORT MAX ACROSS REGION THIS MORNING. LEADING LINE OF SHOWERS AND THUNDERSTORMS THAT MOVED INTO WEST CENTRAL WISCONSIN LAST EVENING ERODED AS THEY MOVED AWAY FROM THIS BETTER FORCING AND WERE OUTRUN BY OUTFLOW BOUNDARY. WIND GUSTS SHOULD ALSO DIMINISH WITH APPROACH OF SURFACE TROUGH AND AS 60-70KT LOW-LEVEL JET HEELS OVER TO THE EAST. HAVE KEPT MENTION OF ISOLATED THUNDERSTORMS THOUGH ELEVATED CAPE ALMOST NON-EXISTENT ON LATEST RAP FORECAST SOUNDINGS. HOWEVER... SPC MESOANALYSIS SHOWS AREA OF 500 J/KG MOST-UNSTABLE CAPE THAT COULD BRUSH SOUTHERN WISCONSIN SO CAN/T RULE OUT A RUMBLE OR TWO OF THUNDER. HAVE PRECIPITATION CHANCES IN THE FAR SOUTHEAST AFTER 18Z UNTIL 850 MB TROUGH CLEARS TO THE EAST. 925 MB TEMPS REBOUND BETWEEN 18Z AND 00Z AND ENOUGH AFTERNOON SUN TO BRING HIGH TEMPS IN THE 60S. . TONIGHT...FORECAST CONFIDENCE ACTUAL COLD FRONT FINALLY DROPS THROUGH SOUTHERN WISCONSIN AFTER MIDNIGHT TONIGHT AFTER PASSAGE OF WEAK SECONDARY WAVE. CLOUDS AND MIXING WITH WEST TO NORTHWEST WINDS OF 5 TO 10 MPH WILL KEEP LOWS INT EH MID TO UPPER 30S. .FRIDAY AND SATURDAY...FORECAST CONFIDENCE...MEDIUM COULD SEE A LITTLE LIGHT RAIN CLIP THE SOUTH FRIDAY MORNING...AS A SHORTWAVE APPROACHES. RAIN CHANCES THEN FOCUS IN THE EAST DURING THE AFTERNOON DUE TO DECENT LOW LEVEL CONVERGENCE. MAY EVEN SEE A MIX WITH SNOW LATER IN THE AFTERNOON TOWARD THE LAKE AS COLDER AIR MOVES IN. SHOULD BE DRY SATURDAY...WITH SOUTHERN WISCONSIN SITTING BETWEEN HIGH PRESSURE TO THE SOUTH AND A PASSING LOW TO THE NORTH. TEMPS WILL BE COOLER FRIDAY...BUT WILL WARM BACK TO A FEW DEGREES ABOVE NORMAL FOR SATURDAY. .SATURDAY NIGHT THROUGH WEDNESDAY...FORECAST CONFIDENCE...MEDIUM COULD SEE SOME PRECIP AT TIMES FROM SATURDAY THROUGH TUESDAY...AS A SERIES OF SYSTEMS MOVE THROUGH A MAINLY STALLED FRONTAL ZONE. THERE REMAINS A BIT OF UNCERTAINTY WITH THIS PORTION OF THE FORECAST DUE TO MODEL DIFFERENCES IN FRONTAL PLACEMENT AND THUS TEMPS AND PRECIP CHANCES. IF THE FRONT SNEAKS FARTHER NORTH...WOULD EXPECT MUCH MILDER TEMPS AND A BETTER CHANCE FOR THUNDER. THE SOUTHERN SOLUTION WOULD RESULT IN PERSISTENT WINDS OFF THE LAKE...COOLER TEMPS...AND LESS INSTABILITY. CONTINUED THE DOWN THE MIDDLE APPROACH BETWEEN THE VARIOUS MODEL SOLUTIONS FOR NOW. LOOKS COOL AND DRY WEDNESDAY UNDER HIGH PRESSURE. && .AVIATION/12Z TAFS/... WILL MAKE SOME ADJUSTMENTS PRIOR TO ISSUANCE ON TIMING OF SHOWERS INTO TAF LOCATIONS AND THEIR IMPACT. EXPECT VFR CONDITIONS WITH ONLY BRIEF MVFR CIGS/VSBYS PER UPSTREAM OBSERVATIONS UNDER THE SHOWERS AND ISOLATED THUNDERSTORMS. HAVE KEPT MENTION OF ISOLATED THUNDERSTORMS THOUGH ELEVATED CAPE ALMOST NON-EXISTENT ON LATEST RAP FORECAST SOUNDINGS. HOWEVER... SPC MESOANALYSIS SHOWS AREA OF 500 J/KG MOST-UNSTABLE CAPE THAT COULD BRUSH SOUTHERN WISCONSIN SO CAN/T RULE OUT A RUMBLE OR TWO OF THUNDER. PCPN SHOULD CLEAR KMSN BY 18Z...AND EASTERN TAF SITES BETWEEN 20Z AND 21Z. LOOKING FOR VFR CONDITIONS THROUGH THE REMAINDER OF THE FORECAST. .FIRE WEATHER... FIRE WEATHER CONDITIONS NOT AS CRITICAL AS YESTERDAY WITH EXPECTED 0.2 TO 0.3 INCH RAINFALLS MOISTENING FUELS. COOLER TEMPERATURES AND LOWER WINDS ALSO LOWERING THE THREAT...THOUGH LOWER DEW POINTS WILL BRING RELATIVE HUMIDITY VALUES DOWN TO AROUND 25 PERCENT IN THE WEST THIS AFTERNOON. && .MARINE... WILL KEEP CURRENT END TIME TO SMALL CRAFT ADVISORY AS WINDS ARE BEGINNING TO EASE WITH SLACKENING GRADIENT ASSOCIATED WITH SURFACE TROUGH. LOWERING WINDS AND VEERING TO AN OFFSHORE DIRECTION AFTER PASSAGE OF SURFACE TROUGH WILL ALLOW WAVES TO SUBSIDE BELOW CRITERIA BY MID-MORNING. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 10 AM CDT THIS MORNING FOR LMZ643>646. && $$ TODAY/TONIGHT AND AVIATION/FIRE WEATHER/MARINE...REM FRIDAY THROUGH WEDNESDAY...DDV
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1025 AM EDT THU APR 2 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 240 AM EST THU APR 2 2015 UNSETTLED WEATHER EXPECTED THROUGH FRIDAY NIGHT AS A FRONTAL SYSTEM DROPS SOUTHEAST ACROSS THE OHIO VALLEY. THUNDERSTORMS WILL RETURN EARLY NEXT WEEK AS WELL WITH ANOTHER SYSTEM. THERE COULD BE A FEW SEVERE STORMS TODAY AND THIS EVENING AS WELL AS NEXT WEEK. HEAVY RAIN IS ALSO POSSIBLE AT TIMES THROUGH FRIDAY. MEANWHILE...HIGH PRESSURE WILL RESULT IN DRY BUT COOLER WEATHER SATURDAY AND SUNDAY. && .NEAR TERM /REST OF TODAY THROUGH FRIDAY NIGHT/... ISSUED AT 955 AM EDT THU APR 2 2015 UPDATE...DELAYED INCREASE OF SHOWERS AND THUNDERSTORMS A LITTLE THROUGH EARLY AFTERNOON BASED ON RADAR TRENDS AND RAPID REFRESH. ALSO DROPPED MENTION OF HEAVY RAINFALL UNTIL LATE AFTERNOON AND THEN ONLY MENTIONED IT OVER THE SOUTHERN 2/3 OF OUR REGION. TEMPERATURES AND THE REST OF THE NEAR TERM IS ON TRACK AND ONLY MINOR TWEAKS MADE TO GRIDS IN REST OF FORECAST. PREVIOUS NEAR TERM DISCUSSION FOLLOWS... MAIN FOCUS FOR THE NEAR TERM WILL BE THUNDERSTORMS TODAY THROUGH FRIDAY ALONG WITH POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND EVENING AND HEAVY RAIN THIS AFTERNOON THROUGH FRIDAY. DETERMINISTIC MODELS STILL HAVE TIMING DIFFERENCES REGARDING UPPER AND SURFACE WAVES AND CONSEQUENTLY TIMING OF THE COLD FRONT...THAT WAS OVER THE UPPER MIDWEST AND SOUTHERN PLAINS THIS OVERNIGHT. HOWEVER...THE DIFFERENCES IN THE 00Z RUN THIS EVENING...SAVE THE NAM...ARE NOT AS GREAT AS THEY ONCE WERE. THE 00Z GFS IS TRENDING FURTHER NORTH WITH ITS TRACK OF SURFACE WAVES AND THEREFORE FRONTAL POSITION ON FRIDAY PER THE STEADIER 12Z ECMWF. A FEW GEFS MEMBERS WERE CLOSE TO THE OPERATIONAL 12Z ECMWF AS WAS ECMWF ENSEMBLE MEAN. MEANWHILE...THE 00Z CANADIAN IS A BIT QUICKER WITH THE FRONT...ALBEIT SLOWER WITH THE UPSTREAM TROUGH. OVERALL...FEEL A BLEND OF THE 00Z GFS...12Z ECMWF AND 12Z ECENS LOOKS BEST. THE COLD FRONT SHOULD DROP SOUTHEAST TO NEAR MERRIVILLE AROUND 18Z THIS AFTERNOON...TO FAR NORTHERN PARTS OF CENTRAL INDIANA 00Z THIS EVENING...AND TO NEAR THE OHIO RIVER ON FRIDAY...BEFORE IT TEMPORARILY STALLS WITH THE WAVES MOVING ALONG IT. FINALLY...THE FRONT SHOULD MOVE INTO EASTERN KENTUCKY BY 00Z SATURDAY...WHICH SHOULD PUT AN END TO THE SHOWERS ACROSS WESTERN PARTS OF THE FORECAST AREA. THIS REST OF THE AREA SHOULD SEE THE SHOWERS EXIT BY 06Z SATURDAY WITH COOLER AIR MOVING IN BEHIND THE FRONT. SPC SREF ENSEMBLES WERE SHOWING INCREASING MIXED LAYER CAPE TODAY WITH NEAR 500 J/KG NEAR MUNCIE AND AROUND 1000 J/K NEAR VINCENNES AT 21Z THIS AFTERNOON. THIS INSTABILITY SHOULD GRADUALLY WANE TONIGHT WITH NIGHTFALL AND FRIDAY WITH THE FRONT MOVING SOUTHEAST. DEEP MOISTURE AND STRONG FORCING WARRANT CATEGORICAL POPS TODAY THROUGH FRIDAY. AREA OF THUNDERSTORMS...CURRENTLY OVER SOUTHEASTERN MISSOURI AND NORTHEASTERN ARKANSAS AND ASSOCIATED WITH AN UPPER WAVE...SHOULD MOVE TO VINCENNES AND TERRE HAUTE AFTER 5 AM AND EAST OF THE AREA LATE MORNING PER THE 05Z HRRR RAPID REFRESH REFLECTIVITY PROGS. THUNDERSTORMS SHOULD MOVE BACK INTO THE AREA AND OTHERS POP UP THIS AFTERNOON AHEAD OF ANOTHER UPPER WAVE AND AGAIN TONIGHT WITH ANOTHER ONE. THUNDERSTORMS SHOULD BE CONFINED TO THE FAR SOUTHERN TIER OR TWO BY FRIDAY AS THE FRONT SETTLES SOUTHEAST AND STABILITY INCREASES NORTH OF THE FRONT. FINALLY...WILL ONLY CARRY EVENING SHOWER CHANCES ACROSS EAST CENTRAL INDIANA BY FRIDAY NIGHT. REGARDING SEVERE WEATHER POTENTIAL...THE 500-1000 J/KG CAPES COMBINED WITH AROUND 200 METERS SQUARED PER SECONDS SQUARED HELICITY...PER 21Z SPC SREF ENSEMBLES...SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED SEVERE WEATHER THIS AFTERNOON...ESPECIALLY SOUTHWEST OF INDIANAPOLIS...WHERE INSTABILITY SHOULD BE GREATER. SEVERE THREAT SHOULD END THIS EVENING...ESPECIALLY NORTH OF BLOOMINGTON...WITH LOSS OF SOLAR HEATING AND BETTER SHEAR SOUTH OF THERE. OVERALL...SPC DAY1 ENHANCED RISK ACROSS SOUTHERN PARTS OF KNOX...DAVIESS AND MARTIN COUNTIES AND SLIGHT RISK ELSEWHERE OVER CENTRAL INDIANA LOOKS GOOD WITH MAIN SEVERE THREATS BEING DAMAGING WINDS AND LARGE HAIL. HOWEVER...CAN NOT RULE OUT A TORNADO OR TWO AS LIFTED CONDENSATION LEVELS ARE FORECASTED TO LESS THAN 3000 FEET. IF EVEN BRIEF BREAKS OCCUR IN THE CLOUD COVER OCCUR...THIS COULD ALSO AID IN ROTATING STORMS. RAINFALL WILL BE ANOTHER ISSUE THROUGH FRIDAY AS JET STREAKS MOVE THROUGH THE 100 PLUS KNOT UPPER JET THAT WILL BE OVER THE AREA TONIGHT AND FRIDAY...PROVIDING STRONG UPPER DIVERGENCE. JET INTERACTIONS ALONG WITH DEEP MOISTURE...DISPLAYED BY PRECIPITABLE WATER VALUES TO NEAR 1.5 INCHES...OR TWICE OR MORE ABOVE NORMAL FOR EARLY APRIL...SUGGEST HEAVY RAIN MENTION TONIGHT WITH HEAVY RAIN ALSO POSSIBLE MAINLY SOUTH OF INTERSTATE 70 ON FRIDAY. FINALLY...SHOULD SEE BREEZY CONDITIONS TODAY WITH BUFKIT SUGGESTING GUSTS TO 30 MPH OR MORE ARE POSSIBLE THIS AFTERNOON...AFTER THE INVERSION DIES. WENT WITH DAYTIME TEMPERATURES AT OR BELOW 00Z MOS DO TO THICK CLOUD COVER. ALSO...WENT CLOSER TO THE MORE MILD 00Z NAM TEMPERATURES FOR OVERNIGHT LOWS...ESPECIALLY SOUTH OF THE FRONT. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... ISSUED AT 240 AM EST FRI APR 02 2015 FOCUS FOR THE SHORT TERM WILL BE ON TEMPERATURES AS MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA. MODEL RH TIME SECTIONS AND CU DEVELOPMENT PROGS SUGGEST THERE WILL BE LITTLE CLOUD COVER AROUND ON SATURDAY WITH PERHAPS SOME CIRRUS SPILLING OVER TOP OF A MISSISSIPPI RIDGE AND ACROSS CENTRAL INDIANA SATURDAY NIGHT. 850 MILLIBAR TEMPERATURE PROGS BRING IN SUB-ZERO TEMPERATURES SATURDAY MORNING BUT WARM IT UP TO 2 TO 4 DEGREES ABOVE ZERO SATURDAY NIGHT. HOWEVER...WITH SUNNY SKIES...SIMILAR 00Z MOS... SLIGHTLY BELOW NORMAL TEMPERATURES...LOOK OK WITH HIGHS IN THE 50S AND LOWS IN THE 30S. && .LONG TERM /SUNDAY THROUGH THURSDAY/... ISSUED AT 320 AM EDT THU APR 2 2015 NUMEROUS OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE LONG TERM PERIOD AS BROAD LOW PRESSURE DEVELOPS TO THE WEST AND SLOWLY MOVES THROUGH THE REGION. THIS COULD POTENTIALLY EXACERBATE AN EXISTING HYDROLOGIC ISSUE DEPENDING ON HOW MUCH RAIN OCCURS IN THE NEXT 24 TO 48 HOURS. INSTABILITY INDICES SUGGEST THUNDER IS A POSSIBILITY IN NEARLY ALL PERIODS AND FORECAST WILL REFLECT THAT. && .AVIATION.../DISCUSSION FOR THE 021500Z TAF UPDATE/ ISSUED AT 1025 AM EDT THU APR 2 2015 SCATTERED SHOWERS ARE MOVING THROUGH KIND AT THE MOMENT...BUT RADAR SHOWS ADDITIONAL CONVECTION DEVELOPING TO THE WEST. ATMOSPHERE IS BECOMING MORE FAVORABLE FOR THUNDER AT KIND...SO ADDED A TEMPO GROUP STARTING AT 15Z. STILL WATCHING ON DEVELOPMENT OF WIDESPREAD THUNDER AND WILL LIKELY HAVE TO MADE ADDITIONAL ADJUSTMENTS LATER. PREVIOUS DISCUSSION FOLLOWS... VFR INITIALLY WILL GIVE WAY TO MVFR CONDITIONS AND SHOWERS/THUNDERSTORMS...ESPECIALLY THIS AFTERNOON AS THUNDERSTORMS BECOME MORE WIDESPREAD. ISOLATED TO SCATTERED CONVECTION INITIALLY WILL MERIT LITTLE MORE THAN A VICINITY MENTION...WILL INCLUDE THUNDER EXPLICITLY BEGINNING THIS AFTERNOON AS INSTABILITY INCREASES AND TROUGH/FRONTAL BOUNDARY APPROACHES. WINDS WILL BE SOUTHERLY MUCH OF THE DAY AND INTO THE EVENING...EVENTUALLY BECOMING NORTHERLY AFTER FRONTAL PASSAGE. GUSTS WILL INCREASE LATER THIS MORNING WITH SOME GUSTS PUSHING 30KT POSSIBLE THIS AFTERNOON. PRIOR TO GUSTINESS...WILL CONTINUE TO CARRY LOW LEVEL WIND SHEAR PER VAD WIND PROFILE SHOWING 45 TO 50KT WINDS JUST 2KFT OFF THE SURFACE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...MK/JH SHORT TERM...MK LONG TERM...NIELD AVIATION...NIELD/50 VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
955 AM EDT THU APR 2 2015 .UPDATE... NEAR TERM FOR THE REST OF TODAY HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 240 AM EST THU APR 2 2015 UNSETTLED WEATHER EXPECTED THROUGH FRIDAY NIGHT AS A FRONTAL SYSTEM DROPS SOUTHEAST ACROSS THE OHIO VALLEY. THUNDERSTORMS WILL RETURN EARLY NEXT WEEK AS WELL WITH ANOTHER SYSTEM. THERE COULD BE A FEW SEVERE STORMS TODAY AND THIS EVENING AS WELL AS NEXT WEEK. HEAVY RAIN IS ALSO POSSIBLE AT TIMES THROUGH FRIDAY. MEANWHILE...HIGH PRESSURE WILL RESULT IN DRY BUT COOLER WEATHER SATURDAY AND SUNDAY. && .NEAR TERM /REST OF TODAY THROUGH FRIDAY NIGHT/... ISSUED AT 955 AM EDT THU APR 2 2015 .UPDATE...DELAYED INCREASE OF SHOWERS AND THUNDERSTORMS A LITTLE THROUGH EARLY AFTERNOON BASED ON RADAR TRENDS AND RAPID REFRESH. ALSO DROPPED MENTION OF HEAVY RAINFALL UNTIL LATE AFTERNOON AND THEN ONLY MENTIONED IT OVER THE SOUTHERN 2/3 OF OUR REGION. TEMPERATURES AND THE REST OF THE NEAR TERM IS ON TRACK AND ONLY MINOR TWEAKS MADE TO GRIDS IN REST OF FORECAST. PREVIOUS NEAR TERM DISCUSSION FOLLOWS... MAIN FOCUS FOR THE NEAR TERM WILL BE THUNDERSTORMS TODAY THROUGH FRIDAY ALONG WITH POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND EVENING AND HEAVY RAIN THIS AFTERNOON THROUGH FRIDAY. DETERMINISTIC MODELS STILL HAVE TIMING DIFFERENCES REGARDING UPPER AND SURFACE WAVES AND CONSEQUENTLY TIMING OF THE COLD FRONT...THAT WAS OVER THE UPPER MIDWEST AND SOUTHERN PLAINS THIS OVERNIGHT. HOWEVER...THE DIFFERENCES IN THE 00Z RUN THIS EVENING...SAVE THE NAM...ARE NOT AS GREAT AS THEY ONCE WERE. THE 00Z GFS IS TRENDING FURTHER NORTH WITH ITS TRACK OF SURFACE WAVES AND THEREFORE FRONTAL POSITION ON FRIDAY PER THE STEADIER 12Z ECMWF. A FEW GEFS MEMBERS WERE CLOSE TO THE OPERATIONAL 12Z ECMWF AS WAS ECMWF ENSEMBLE MEAN. MEANWHILE...THE 00Z CANADIAN IS A BIT QUICKER WITH THE FRONT...ALBEIT SLOWER WITH THE UPSTREAM TROUGH. OVERALL...FEEL A BLEND OF THE 00Z GFS...12Z ECMWF AND 12Z ECENS LOOKS BEST. THE COLD FRONT SHOULD DROP SOUTHEAST TO NEAR MERRIVILLE AROUND 18Z THIS AFTERNOON...TO FAR NORTHERN PARTS OF CENTRAL INDIANA 00Z THIS EVENING...AND TO NEAR THE OHIO RIVER ON FRIDAY...BEFORE IT TEMPORARILY STALLS WITH THE WAVES MOVING ALONG IT. FINALLY...THE FRONT SHOULD MOVE INTO EASTERN KENTUCKY BY 00Z SATURDAY...WHICH SHOULD PUT AN END TO THE SHOWERS ACROSS WESTERN PARTS OF THE FORECAST AREA. THIS REST OF THE AREA SHOULD SEE THE SHOWERS EXIT BY 06Z SATURDAY WITH COOLER AIR MOVING IN BEHIND THE FRONT. SPC SREF ENSEMBLES WERE SHOWING INCREASING MIXED LAYER CAPE TODAY WITH NEAR 500 J/KG NEAR MUNCIE AND AROUND 1000 J/K NEAR VINCENNES AT 21Z THIS AFTERNOON. THIS INSTABILITY SHOULD GRADUALLY WANE TONIGHT WITH NIGHTFALL AND FRIDAY WITH THE FRONT MOVING SOUTHEAST. DEEP MOISTURE AND STRONG FORCING WARRANT CATEGORICAL POPS TODAY THROUGH FRIDAY. AREA OF THUNDERSTORMS...CURRENTLY OVER SOUTHEASTERN MISSOURI AND NORTHEASTERN ARKANSAS AND ASSOCIATED WITH AN UPPER WAVE...SHOULD MOVE TO VINCENNES AND TERRE HAUTE AFTER 5 AM AND EAST OF THE AREA LATE MORNING PER THE 05Z HRRR RAPID REFRESH REFLECTIVITY PROGS. THUNDERSTORMS SHOULD MOVE BACK INTO THE AREA AND OTHERS POP UP THIS AFTERNOON AHEAD OF ANOTHER UPPER WAVE AND AGAIN TONIGHT WITH ANOTHER ONE. THUNDERSTORMS SHOULD BE CONFINED TO THE FAR SOUTHERN TIER OR TWO BY FRIDAY AS THE FRONT SETTLES SOUTHEAST AND STABILITY INCREASES NORTH OF THE FRONT. FINALLY...WILL ONLY CARRY EVENING SHOWER CHANCES ACROSS EAST CENTRAL INDIANA BY FRIDAY NIGHT. REGARDING SEVERE WEATHER POTENTIAL...THE 500-1000 J/KG CAPES COMBINED WITH AROUND 200 METERS SQUARED PER SECONDS SQUARED HELICITY...PER 21Z SPC SREF ENSEMBLES...SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED SEVERE WEATHER THIS AFTERNOON...ESPECIALLY SOUTHWEST OF INDIANAPOLIS...WHERE INSTABILITY SHOULD BE GREATER. SEVERE THREAT SHOULD END THIS EVENING...ESPECIALLY NORTH OF BLOOMINGTON...WITH LOSS OF SOLAR HEATING AND BETTER SHEAR SOUTH OF THERE. OVERALL...SPC DAY1 ENHANCED RISK ACROSS SOUTHERN PARTS OF KNOX...DAVIESS AND MARTIN COUNTIES AND SLIGHT RISK ELSEWHERE OVER CENTRAL INDIANA LOOKS GOOD WITH MAIN SEVERE THREATS BEING DAMAGING WINDS AND LARGE HAIL. HOWEVER...CAN NOT RULE OUT A TORNADO OR TWO AS LIFTED CONDENSATION LEVELS ARE FORECASTED TO LESS THAN 3000 FEET. IF EVEN BRIEF BREAKS OCCUR IN THE CLOUD COVER OCCUR...THIS COULD ALSO AID IN ROTATING STORMS. RAINFALL WILL BE ANOTHER ISSUE THROUGH FRIDAY AS JET STREAKS MOVE THROUGH THE 100 PLUS KNOT UPPER JET THAT WILL BE OVER THE AREA TONIGHT AND FRIDAY...PROVIDING STRONG UPPER DIVERGENCE. JET INTERACTIONS ALONG WITH DEEP MOISTURE...DISPLAYED BY PRECIPITABLE WATER VALUES TO NEAR 1.5 INCHES...OR TWICE OR MORE ABOVE NORMAL FOR EARLY APRIL...SUGGEST HEAVY RAIN MENTION TONIGHT WITH HEAVY RAIN ALSO POSSIBLE MAINLY SOUTH OF INTERSTATE 70 ON FRIDAY. FINALLY...SHOULD SEE BREEZY CONDITIONS TODAY WITH BUFKIT SUGGESTING GUSTS TO 30 MPH OR MORE ARE POSSIBLE THIS AFTERNOON...AFTER THE INVERSION DIES. WENT WITH DAYTIME TEMPERATURES AT OR BELOW 00Z MOS DO TO THICK CLOUD COVER. ALSO...WENT CLOSER TO THE MORE MILD 00Z NAM TEMPERATURES FOR OVERNIGHT LOWS...ESPECIALLY SOUTH OF THE FRONT. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... ISSUED AT 240 AM EST FRI APR 02 2015 FOCUS FOR THE SHORT TERM WILL BE ON TEMPERATURES AS MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA. MODEL RH TIME SECTIONS AND CU DEVELOPMENT PROGS SUGGEST THERE WILL BE LITTLE CLOUD COVER AROUND ON SATURDAY WITH PERHAPS SOME CIRRUS SPILLING OVER TOP OF A MISSISSIPPI RIDGE AND ACROSS CENTRAL INDIANA SATURDAY NIGHT. 850 MILLIBAR TEMPERATURE PROGS BRING IN SUB-ZERO TEMPERATURES SATURDAY MORNING BUT WARM IT UP TO 2 TO 4 DEGREES ABOVE ZERO SATURDAY NIGHT. HOWEVER...WITH SUNNY SKIES...SIMILAR 00Z MOS... SLIGHTLY BELOW NORMAL TEMPERATURES...LOOK OK WITH HIGHS IN THE 50S AND LOWS IN THE 30S. && .LONG TERM /SUNDAY THROUGH THURSDAY/... ISSUED AT 320 AM EDT THU APR 2 2015 NUMEROUS OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE LONG TERM PERIOD AS BROAD LOW PRESSURE DEVELOPS TO THE WEST AND SLOWLY MOVES THROUGH THE REGION. THIS COULD POTENTIALLY EXACERBATE AN EXISTING HYDROLOGIC ISSUE DEPENDING ON HOW MUCH RAIN OCCURS IN THE NEXT 24 TO 48 HOURS. INSTABILITY INDICES SUGGEST THUNDER IS A POSSIBILITY IN NEARLY ALL PERIODS AND FORECAST WILL REFLECT THAT. && .AVIATION.../DISCUSSION FOR THE 02/12Z TAFS/ ISSUED AT 709 AM EDT THU APR 2 2015 VFR INITIALLY WILL GIVE WAY TO MVFR CONDITIONS AND SHOWERS/THUNDERSTORMS...ESPECIALLY THIS AFTERNOON AS THUNDERSTORMS BECOME MORE WIDESPREAD. ISOLATED TO SCATTERED CONVECTION INITIALLY WILL MERIT LITTLE MORE THAN A VICINITY MENTION...WILL INCLUDE THUNDER EXPLICITLY BEGINNING THIS AFTERNOON AS INSTABILITY INCREASES AND TROUGH/FRONTAL BOUNDARY APPROACHES. WINDS WILL BE SOUTHERLY MUCH OF THE DAY AND INTO THE EVENING...EVENTUALLY BECOMING NORTHERLY AFTER FRONTAL PASSAGE. GUSTS WILL INCREASE LATER THIS MORNING WITH SOME GUSTS PUSHING 30KT POSSIBLE THIS AFTERNOON. PRIOR TO GUSTINESS...WILL CONTINUE TO CARRY LOW LEVEL WIND SHEAR PER VAD WIND PROFILE SHOWING 45 TO 50KT WINDS JUST 2KFT OFF THE SURFACE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...MK/JH SHORT TERM...MK LONG TERM...NIELD AVIATION...NIELD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
709 AM EDT THU APR 2 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 240 AM EST THU APR 2 2015 UNSETTLED WEATHER EXPECTED THROUGH FRIDAY NIGHT AS A FRONTAL SYSTEM DROPS SOUTHEAST ACROSS THE OHIO VALLEY. THUNDERSTORMS WILL RETURN EARLY NEXT WEEK AS WELL WITH ANOTHER SYSTEM. THERE COULD BE A FEW SEVERE STORMS TODAY AND THIS EVENING AS WELL AS NEXT WEEK. HEAVY RAIN IS ALSO POSSIBLE AT TIMES THROUGH FRIDAY. MEANWHILE...HIGH PRESSURE WILL RESULT IN DRY BUT COOLER WEATHER SATURDAY AND SUNDAY. && .NEAR TERM /TODAY THROUGH FRIDAY NIGHT/... ISSUED AT 240 AM EDT THU APR 2 2015 MAIN FOCUS FOR THE NEAR TERM WILL BE THUNDERSTORMS TODAY THROUGH FRIDAY ALONG WITH POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND EVENING AND HEAVY RAIN THIS AFTERNOON THROUGH FRIDAY. DETERMINISTIC MODELS STILL HAVE TIMING DIFFERENCES REGARDING UPPER AND SURFACE WAVES AND CONSEQUENTLY TIMING OF THE COLD FRONT...THAT WAS OVER THE UPPER MIDWEST AND SOUTHERN PLAINS THIS OVERNIGHT. HOWEVER...THE DIFFERENCES IN THE 00Z RUN THIS EVENING...SAVE THE NAM...ARE NOT AS GREAT AS THEY ONCE WERE. THE 00Z GFS IS TRENDING FURTHER NORTH WITH ITS TRACK OF SURFACE WAVES AND THEREFORE FRONTAL POSITION ON FRIDAY PER THE STEADIER 12Z ECMWF. A FEW GEFS MEMBERS WERE CLOSE TO THE OPERATIONAL 12Z ECMWF AS WAS ECMWF ENSEMBLE MEAN. MEANWHILE...THE 00Z CANADIAN IS A BIT QUICKER WITH THE FRONT...ALBEIT SLOWER WITH THE UPSTREAM TROUGH. OVERALL...FEEL A BLEND OF THE 00Z GFS...12Z ECMWF AND 12Z ECENS LOOKS BEST. THE COLD FRONT SHOULD DROP SOUTHEAST TO NEAR MERRIVILLE AROUND 18Z THIS AFTERNOON...TO FAR NORTHERN PARTS OF CENTRAL INDIANA 00Z THIS EVENING...AND TO NEAR THE OHIO RIVER ON FRIDAY...BEFORE IT TEMPORARILY STALLS WITH THE WAVES MOVING ALONG IT. FINALLY...THE FRONT SHOULD MOVE INTO EASTERN KENTUCKY BY 00Z SATURDAY...WHICH SHOULD PUT AN END TO THE SHOWERS ACROSS WESTERN PARTS OF THE FORECAST AREA. THIS REST OF THE AREA SHOULD SEE THE SHOWERS EXIT BY 06Z SATURDAY WITH COOLER AIR MOVING IN BEHIND THE FRONT. SPC SREF ENSEMBLES WERE SHOWING INCREASING MIXED LAYER CAPE TODAY WITH NEAR 500 J/KG NEAR MUNCIE AND AROUND 1000 J/K NEAR VINCENNES AT 21Z THIS AFTERNOON. THIS INSTABILITY SHOULD GRADUALLY WANE TONIGHT WITH NIGHTFALL AND FRIDAY WITH THE FRONT MOVING SOUTHEAST. DEEP MOISTURE AND STRONG FORCING WARRANT CATEGORICAL POPS TODAY THROUGH FRIDAY. AREA OF THUNDERSTORMS...CURRENTLY OVER SOUTHEASTERN MISSOURI AND NORTHEASTERN ARKANSAS AND ASSOCIATED WITH AN UPPER WAVE...SHOULD MOVE TO VINCENNES AND TERRE HAUTE AFTER 5 AM AND EAST OF THE AREA LATE MORNING PER THE 05Z HRRR RAPID REFRESH REFLECTIVITY PROGS. THUNDERSTORMS SHOULD MOVE BACK INTO THE AREA AND OTHERS POP UP THIS AFTERNOON AHEAD OF ANOTHER UPPER WAVE AND AGAIN TONIGHT WITH ANOTHER ONE. THUNDERSTORMS SHOULD BE CONFINED TO THE FAR SOUTHERN TIER OR TWO BY FRIDAY AS THE FRONT SETTLES SOUTHEAST AND STABILITY INCREASES NORTH OF THE FRONT. FINALLY...WILL ONLY CARRY EVENING SHOWER CHANCES ACROSS EAST CENTRAL INDIANA BY FRIDAY NIGHT. REGARDING SEVERE WEATHER POTENTIAL...THE 500-1000 J/KG CAPES COMBINED WITH AROUND 200 METERS SQUARED PER SECONDS SQUARED HELICITY...PER 21Z SPC SREF ENSEMBLES...SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED SEVERE WEATHER THIS AFTERNOON...ESPECIALLY SOUTHWEST OF INDIANAPOLIS...WHERE INSTABILITY SHOULD BE GREATER. SEVERE THREAT SHOULD END THIS EVENING...ESPECIALLY NORTH OF BLOOMINGTON...WITH LOSS OF SOLAR HEATING AND BETTER SHEAR SOUTH OF THERE. OVERALL...SPC DAY1 ENHANCED RISK ACROSS SOUTHERN PARTS OF KNOX...DAVIESS AND MARTIN COUNTIES AND SLIGHT RISK ELSEWHERE OVER CENTRAL INDIANA LOOKS GOOD WITH MAIN SEVERE THREATS BEING DAMAGING WINDS AND LARGE HAIL. HOWEVER...CAN NOT RULE OUT A TORNADO OR TWO AS LIFTED CONDENSATION LEVELS ARE FORECASTED TO LESS THAN 3000 FEET. IF EVEN BRIEF BREAKS OCCUR IN THE CLOUD COVER OCCUR...THIS COULD ALSO AID IN ROTATING STORMS. RAINFALL WILL BE ANOTHER ISSUE THROUGH FRIDAY AS JET STREAKS MOVE THROUGH THE 100 PLUS KNOT UPPER JET THAT WILL BE OVER THE AREA TONIGHT AND FRIDAY...PROVIDING STRONG UPPER DIVERGENCE. JET INTERACTIONS ALONG WITH DEEP MOISTURE...DISPLAYED BY PRECIPITABLE WATER VALUES TO NEAR 1.5 INCHES...OR TWICE OR MORE ABOVE NORMAL FOR EARLY APRIL...SUGGEST HEAVY RAIN MENTION TONIGHT WITH HEAVY RAIN ALSO POSSIBLE MAINLY SOUTH OF INTERSTATE 70 ON FRIDAY. FINALLY...SHOULD SEE BREEZY CONDITIONS TODAY WITH BUFKIT SUGGESTING GUSTS TO 30 MPH OR MORE ARE POSSIBLE THIS AFTERNOON...AFTER THE INVERSION DIES. WENT WITH DAYTIME TEMPERATURES AT OR BELOW 00Z MOS DO TO THICK CLOUD COVER. ALSO...WENT CLOSER TO THE MORE MILD 00Z NAM TEMPERATURES FOR OVERNIGHT LOWS...ESPECIALLY SOUTH OF THE FRONT. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... ISSUED AT 240 AM EST FRI APR 02 2015 FOCUS FOR THE SHORT TERM WILL BE ON TEMPERATURES AS MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA. MODEL RH TIME SECTIONS AND CU DEVELOPMENT PROGS SUGGEST THERE WILL BE LITTLE CLOUD COVER AROUND ON SATURDAY WITH PERHAPS SOME CIRRUS SPILLING OVER TOP OF A MISSISSIPPI RIDGE AND ACROSS CENTRAL INDIANA SATURDAY NIGHT. 850 MILLIBAR TEMPERATURE PROGS BRING IN SUB-ZERO TEMPERATURES SATURDAY MORNING BUT WARM IT UP TO 2 TO 4 DEGREES ABOVE ZERO SATURDAY NIGHT. HOWEVER...WITH SUNNY SKIES...SIMILAR 00Z MOS... SLIGHTLY BELOW NORMAL TEMPERATURES...LOOK OK WITH HIGHS IN THE 50S AND LOWS IN THE 30S. && .LONG TERM /SUNDAY THROUGH THURSDAY/... ISSUED AT 320 AM EDT THU APR 2 2015 NUMEROUS OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE LONG TERM PERIOD AS BROAD LOW PRESSURE DEVELOPS TO THE WEST AND SLOWLY MOVES THROUGH THE REGION. THIS COULD POTENTIALLY EXACERBATE AN EXISTING HYDROLOGIC ISSUE DEPENDING ON HOW MUCH RAIN OCCURS IN THE NEXT 24 TO 48 HOURS. INSTABILITY INDICES SUGGEST THUNDER IS A POSSIBILITY IN NEARLY ALL PERIODS AND FORECAST WILL REFLECT THAT. && .AVIATION.../DISCUSSION FOR THE 02/12Z TAFS/ ISSUED AT 709 AM EDT THU APR 2 2015 VFR INITIALLY WILL GIVE WAY TO MVFR CONDITIONS AND SHOWERS/THUNDERSTORMS...ESPECIALLY THIS AFTERNOON AS THUNDERSTORMS BECOME MORE WIDESPREAD. ISOLATED TO SCATTERED CONVECTION INITIALLY WILL MERIT LITTLE MORE THAN A VICINITY MENTION...WILL INCLUDE THUNDER EXPLICITLY BEGINNING THIS AFTERNOON AS INSTABILITY INCREASES AND TROUGH/FRONTAL BOUNDARY APPROACHES. WINDS WILL BE SOUTHERLY MUCH OF THE DAY AND INTO THE EVENING...EVENTUALLY BECOMING NORTHERLY AFTER FRONTAL PASSAGE. GUSTS WILL INCREASE LATER THIS MORNING WITH SOME GUSTS PUSHING 30KT POSSIBLE THIS AFTERNOON. PRIOR TO GUSTINESS...WILL CONTINUE TO CARRY LOW LEVEL WIND SHEAR PER VAD WIND PROFILE SHOWING 45 TO 50KT WINDS JUST 2KFT OFF THE SURFACE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...MK SHORT TERM...MK LONG TERM...NIELD AVIATION...NIELD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
629 AM EDT THU APR 2 2015 .SYNOPSIS... ISSUED AT 400 AM EDT THU APR 2 2015 RAIN IS EXPECTED TO SPREAD ACROSS THE REGION TODAY AHEAD OF A COLD FRONT. THUNDERSTORMS WILL ALSO BE POSSIBLE AT TIMES. HIGH TEMPERATURES WILL GENERALLY BE IN THE 60S. RAIN WILL CONTINUE TONIGHT NEAR AND SOUTH OF THE FRONT AS IT SAGS INTO CENTRAL PORTIONS OF ILLINOIS...INDIANA AND OHIO. LOWS WILL RANGE FROM THE MIDDLE AND UPPER 30S NORTH TO THE UPPER 40S SOUTH. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 359 AM EDT THU APR 2 2015 UPSTREAM RADAR IS STILL PRETTY BENIGN...BUT HI RES GUIDANCE INCLUDING THE HRRR CONTINUE SHOW INCREASING COVERAGE OF SCATTERED SHOWERS AND TSTORMS BETWEEN NOW AND DAYBREAK ALONG THE LEADING EDGE OF 850MB MOISTURE ADVECTION ASSOCIATED WITH THE MID LEVEL WAVE CURRENTLY LOCATED NEAR SAINT LOUIS. THIS WAVE OF CONVECTION WILL BE OUT OF THE AREA BY MID DAY...BUT WILL QUICKLY BE REPLACED BY ADDITIONAL CONVECTION ASSOCIATED WITH THE OUTFLOW BOUNDARY/SYNOPTIC COLD FRONT MOVING OUT OF THE UPPER MIDWEST. LATEST SPC OUTLOOK HAS THE SOUTHERN HALF OF OUR FORECAST AREA IN A MARGINAL RISK FOR SEVERE WEATHER. THIS RISK SEEMS APPROPRIATE GIVEN THE CONDITIONAL THREAT. SURFACE DEWPOINTS WILL INCREASE INTO THE UPPER 50S BY MID DAY...BUT MEAGER MID-LEVEL LAPSE RATES...AND LIMITED SURFACE HEATING WILL LIMIT SEVERE POTENTIAL. CURRENT SATELLITE VIEW SHOWS THE CLOUDCOVER ASSOCIATED WITH THE MCS IN IOWA WILL BE RIGHT ON THE HEELS OF THE MID LEVEL WAVE MOVING THROUGH ILLINOIS...THUS PROVIDING LITTLE TIME FOR MUCH SOLAR INSOLATION. IF BREAKS IN THE CLOUDS DO OCCUR...A LOW END SEVERE WIND THREAT MAY MATERIALIZE GIVEN THE 35 TO 40 KNOTS OF DEEP LAYER SHEAR AND ~40 KNOTS OF FLOW ~2500 FEET OFF THE DECK. THURSDAY WILL BE WINDY WITH GUSTS TO 25 TO 30 MPH. IF AFOREMENTIONED BREAKS IN THE CLOUDS OCCUR...THIS WILL ALLOW FOR DEEPER MIXING AND STRONGER WIND GUSTS OF 35 TO 40 MPH. WINDS WILL DIE DOWN SIGNIFICANTLY BY THE EVENING HOURS ONCE THE COLD FRONT SLIDES THROUGH THE AREA. && .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 359 AM EDT THU APR 2 2015 SECONDARY WAVE WILL BE MOVING THROUGH THE REGION FRIDAY. MAIN FRONTAL BOUNDARY WILL BE TO OUR SOUTH BUT MOISTURE ADVECTION WILL SPREAD NORTH AND SHOULD SEE PCPN RE-DEVELOP ESPECIALLY OVER SOUTH AND SOUTHEAST DURING THE AFTERNOON. COUPLED UPPER LEVEL JET TO PROVIDE GOOD DIFFLUENCE ALOFT AND HAVE CONTINUED CATEGORICAL POPS SOUTH. THERMAL PROFILES STILL SUPPORT MAINLY RAIN ON FRIDAY. HOWEVER...TEMP PROFILES DO BEGIN TO HINT AT POSSIBLE WET SNOW MIX IF STRONG LIFT IS SUFFICIENT TO COOL LOWER LEVELS IN AFTERNOON. THIS TIMING IS NOT FAVORABLE GIVEN TIME OF YEAR AND WITH WARM BOUNDARY LAYER PREFER TO HOLD OFF ANY SNOW MENTION UNTIL EVENING HOURS WHEN COLDER AIR DEEPENS. AS PREVIOUSLY MENTIONED THIS WILL COINCIDE WITH DEEPER MOISTURE EXITING THE AREA SO NOT EXPECTING ANY ACCUMS AT THIS TIME. HIGH PRESSURE MOVES BACK IN FOR SATURDAY. WARM FRONT WILL BEGIN TO TAKE SHAPE OVER THE GREAT LAKES SATURDAY NIGHT INTO SUNDAY. THIS BOUNDARY TO BECOME PROBLEMATIC FOR REMAINDER OF FORECAST AS DEEPER SOUTHWEST FLOW DEVELOPS AND FRONT BECOMES QUASI STATIONARY OVER THE AREA AS TYPICAL FOR THIS TIME OF YEAR. OBVIOUS PROBLEMS SURROUND STRONG THERMAL CONTRAST ACROSS THIS BOUNDARY AND TEMP/POP FORECAST DEPENDENT ON ITS LOCATION. STAYED CLOSE TO PREVIOUS FORECAST FOR CONSISTENCY WITH FEW CHANGES TO THE LATER PERIODS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 626 AM EDT THU APR 2 2015 AS EXPECTED SEEING SHOWERS AND EMBEDDED TSRA DEVELOPING EARLY THIS MORNING ALONG INITIAL THETA E SURGE. ADDITIONAL PCPN DEVELOPMENT UPSTREAM AS WELL. WILL SEE SEVERAL PERIODS OF PCPN TODAY AND HAVE CONTINUED TRENDS IN TAFS. FRONT WILL PUSH PCPN SOUTH OF TAF SITES THIS EVENING BUT COULD LINGER AT KFWA DEPENDING ON HOW FAST DRIER AIR WORKS IN. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ043- 046. && $$ SYNOPSIS...LASHLEY SHORT TERM...BENTLEY LONG TERM...LASHLEY AVIATION...BENTLEY/LASHLEY VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1018 AM CDT THU APR 2 2015 .UPDATE... ISSUED AT 1018 AM CDT THU APR 2 2015 DOPPLER RADAR INDICATED THE RAIN HAS DIMINISHED RAPIDLY IN OUR FAR EASTERN COUNTIES WITH THE REMAINDER OF THE CWA DRY. HAVE UPDATED THE GRIDS TO REFLECT THIS TREND...REDUCING POPS TO SLIGHTS IN OUR FAR EASTERN CWA THE REMAINDER OF THE MORNING. LOW CLOUDS WILL BE PUSHING OFF TO OUR EAST FOLLOWED BY A PERIOD OF HIGH LEVEL CLOUDS BEFORE CLEARING THIS AFTERNOON FROM WEST TO EAST. BUREAU COUNTY RECEIVED THE MOST RAIN LAST NIGHT...AROUND ONE-HALF INCH. THE REMAINDER OF THE CWA REPORTED LESS THAN 1/4 INCH WITH SOME SPOTS NOT A DROP OF RAIN. UPDATE ISSUED AT 534 AM CDT THU APR 2 2015 UPDATE FOR MINOR CHANGES TO POPS AND RAINFALL AMOUNTS. ALSO SCALED THUNDER MENTION BACK TO ISOLATED. RAIN COVERAGE HAS INCREASED SOMEWHAT OVER THE PAST COUPLE OF HOURS. INTENSITY HAS PICKED UP ACROSS THE SOUTH WITH INCREASED FORCING FROM APPROACHING SHORTWAVE...WHILE THE STORMS IN THE FAR EAST LOOK TO BE FUELED BY THE NOSE OF A NEAR 50 KT LOW LEVEL JET. RAIN STILL ON TRACK TO MOVE EAST OF THE FORECAST AREA AROUND MIDDAY. && .SYNOPSIS... ISSUED AT 232 AM CDT THU APR 2 2015 AT 300 AM CDT...A COLD FRONT HAD PUSHED INTO CENTRAL IOWA. MORE FAVORABLE MOISTURE AHEAD OF THE BOUNDARY HAD FINALLY MADE IT INTO EASTERN IOWA...WITH DEWPOINTS IN THE LOW/MID 50S. SHOWERS/SCATTERED THUNDERSTORMS ALONG AND EAST OF THE FRONT WERE MOVING INTO THE FAR WESTERN FRINGE OF THE FORECAST AREA...FUELED BY A RIBBON OF MU CAPE AOA 500 J/KG AND A SWATH OF STEEPER MID LEVEL LAPSE RATE. A SHORT WAVE TROUGH LIFTING THROUGH ILLINOIS IS SUPPORTING ISOLATED CONVECTION ACROSS THE FAR EASTERN COUNTIES. EARLY MORNING TEMPERATURES WERE IN THE 50S TO LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 232 AM CDT THU APR 2 2015 THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS PRECIP TRENDS/COVERAGE/AMOUNTS THROUGH EARLY AFTERNOON. IN THE NEAR TERM...HIGH RESOLUTION MODELS INCLUDING THE HRRR AND ARW/NMM ARE RUNNING A BIT SLOW BUT OTHERWISE HAVE THE CURRENT WEATHER MODELED WELL. HAVE ADJUSTED POPS FOR NEAR TERM TRENDS. HIGHEST QPF THROUGH 12Z WILL BE FOCUSED ACROSS THE WEST AND THE FAR EASTERN FRINGE...WITH SPOTTIER RAIN COVERAGE CENTRAL. AFTER 12Z...HIGHEST QPF AND SHOWER/STORM COVERAGE SHOULD BE LOCATED ALONG/EAST OF THE MISSISSIPPI RIVER AS THE UPSTREAM SHORTWAVE INTERACTS WITH THE COLD FRONT. TOTAL QPF NOW LOOKS LIKE IT WILL FALL MAINLY IN THE TENTH TO THIRD OF AN INCH RANGE. THE CHANCE OF ANY SEVERE WEATHER IS VIRTUALLY NIL. RAIN WILL END IN THE SOUTHEAST/EAST DURING THE EARLY AFTERNOON. BLENDED TEMPERATURE GUIDANCE IN THE MID/UPPER 60S FOR AFTERNOON HIGHS LOOKS REASONABLE. FOR TONIGHT...SOME LIGHT RAIN MAY SPREAD INTO THE WEST LATE...AHEAD OF ANOTHER WEAK SHORTWAVE TROUGH. EXPECT LOWS IN THE UPPER 30S/MID 40S. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 232 AM CDT THU APR 2 2015 AN ACTIVE WEATHER PATTERN FOR THE LONG TERM IS THE MAIN FORECAST CONCERN. THE BEGINNING OF THE PERIOD SEES ONE SYSTEM WITH NUMEROUS FORECAST ISSUES MOVING OUT OF THE AREA...FOLLOWED BY A FEW QUICK SYSTEMS...THEN AN ACTIVE WEEK NEXT WEEK WITH NUMEROUS SYSTEMS AND CHANCES FOR RAIN. LIKE ADVERTISED LAST NIGHT IN THE AFD...A COLD FRONT STALLS OUT TO OUR SOUTH AS THE MAIN FORCING MOVES QUICKLY TO THE EAST. AT THE SAME TIME ANOTHER WAVE IS MOVING ACROSS THE CENTRAL UNITED STATES. THIS WAVE INTERACTS WITH THE SURFACE FRONT...BRINGING IT SLIGHTLY NORTH AND THEN INDUCING SURFACE CYCLOGENESIS AND MOVING THE FRONT OUT OF THE AREA. THE GEM AND THE GFS ARE THE TWO MODELS WITH THE MOST PRECIP NORTH INTO OUR AREA. WHILE TEMPERATURES WILL BE WELL ABOVE FREEZING...THE SREF MEAN SUGGESTS THAT THE TEMPS IN EARLY AFTERNOON WILL BE CONDUCIVE TO SNOWFALL. THE REST OF THE DETERMINISTIC MODELS HAVE US ABOVE FREEZING. THE OPERATIONAL NAM...A MEMBER OF THE SREF...HAS NO QPF FOR US DURING THIS TIME. SO THERE IS A LARGE SPREAD IN THE MEMBERS IN THE SREF. THINK THE SREF MEAN IS BEING SWAYED HEAVILY BY ONE MEMBER...SO DONT THINK WE WILL SEE SNOW. FRIDAY EVENING THROUGH SUNDAY AFTERNOON LOOKS TO BE DRY FOR OUR AREA. ANOTHER CLIPPER MOVES THROUGH WISCONSIN. LATEST RUNS BRING THE QPF WITH THIS SYSTEM FURTHER NORTH...SO ONLY OUR FAR NORTHERN ZONES HAVE A SLIGHT CHANCE FOR POPS. WITH THE THERMAL PROFILE IT APPEARS THAT RASN MIX WOULD BE PREFERRED FOR ANY PRECIP THAT FALLS. MONDAY THROUGH TUESDAY EVENING...AN ACTIVE PATTERN SETS UP OVER THE AREA AND IT LOOKS LIKE WE SEE QPF THROUGH THE PERIOD. MODELS ARE IN AGREEMENT IN THE OVERALL LARGE SCALE PATTERN...HOWEVER THE FINESCALE FEATURES ARE YET TO BE AGREED UPON. IT LOOKS LIKE THE BEST CHANCE FOR THUNDER AT THIS TIME WILL BE MONDAY AFTERNOON THROUGH THE NIGHT. WEDNESDAY AND THURSDAY...THE MODELS HAVE FLIP FLOPPED ON LARGE SCALE FEATURES AND ARE DIFFERENT IN SOLUTIONS WITH THE ECMWF BEING WET AND THE GFS BEING DRY. OBVIOUSLY AS WE GET CLOSER THIS WILL BE THE NEXT FORECAST CONCERN BY EARLY NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 711 AM CDT THU APR 2 2015 PERIODS OF MVFR CIGS/VSBYS IN SHOWERS WILL END QUICKLY FROM WEST TO EAST THIS MORNING...FOLLOWED BY PARTIAL CLEARING AND A GUSTY NORTHWEST WIND WHICH WILL DIMINISH UNDER 10 KTS BY LATE AFTERNOON. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...HAASE SYNOPSIS...RP KINNEY SHORT TERM...RP KINNEY LONG TERM...GIBBS AVIATION...RP KINNEY
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
730 AM CDT THU APR 2 2015 .UPDATE... ISSUED AT 534 AM CDT THU APR 2 2015 UPDATE FOR MINOR CHANGES TO POPS AND RAINFALL AMOUNTS. ALSO SCALED THUNDER MENTION BACK TO ISOLATED. RAIN COVERAGE HAS INCREASED SOMEWHAT OVER THE PAST COUPLE OF HOURS. INTENSITY HAS PICKED UP ACROSS THE SOUTH WITH INCREASED FORCING FROM APPROACHING SHORTWAVE...WHILE THE STORMS IN THE FAR EAST LOOK TO BE FUELED BY THE NOSE OF A NEAR 50 KT LOW LEVEL JET. RAIN STILL ON TRACK TO MOVE EAST OF THE FORECAST AREA AROUND MIDDAY. && .SYNOPSIS... ISSUED AT 232 AM CDT THU APR 2 2015 AT 300 AM CDT...A COLD FRONT HAD PUSHED INTO CENTRAL IOWA. MORE FAVORABLE MOISTURE AHEAD OF THE BOUNDARY HAD FINALLY MADE IT INTO EASTERN IOWA...WITH DEWPOINTS IN THE LOW/MID 50S. SHOWERS/SCATTERED THUNDERSTORMS ALONG AND EAST OF THE FRONT WERE MOVING INTO THE FAR WESTERN FRINGE OF THE FORECAST AREA...FUELED BY A RIBBON OF MU CAPE AOA 500 J/KG AND A SWATH OF STEEPER MID LEVEL LAPSE RATE. A SHORT WAVE TROUGH LIFTING THROUGH ILLINOIS IS SUPPORTING ISOLATED CONVECTION ACROSS THE FAR EASTERN COUNTIES. EARLY MORNING TEMPERATURES WERE IN THE 50S TO LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 232 AM CDT THU APR 2 2015 THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS PRECIP TRENDS/COVERAGE/AMOUNTS THROUGH EARLY AFTERNOON. IN THE NEAR TERM...HIGH RESOLUTION MODELS INCLUDING THE HRRR AND ARW/NMM ARE RUNNING A BIT SLOW BUT OTHERWISE HAVE THE CURRENT WEATHER MODELED WELL. HAVE ADJUSTED POPS FOR NEAR TERM TRENDS. HIGHEST QPF THROUGH 12Z WILL BE FOCUSED ACROSS THE WEST AND THE FAR EASTERN FRINGE...WITH SPOTTIER RAIN COVERAGE CENTRAL. AFTER 12Z...HIGHEST QPF AND SHOWER/STORM COVERAGE SHOULD BE LOCATED ALONG/EAST OF THE MISSISSIPPI RIVER AS THE UPSTREAM SHORTWAVE INTERACTS WITH THE COLD FRONT. TOTAL QPF NOW LOOKS LIKE IT WILL FALL MAINLY IN THE TENTH TO THIRD OF AN INCH RANGE. THE CHANCE OF ANY SEVERE WEATHER IS VIRTUALLY NIL. RAIN WILL END IN THE SOUTHEAST/EAST DURING THE EARLY AFTERNOON. BLENDED TEMPERATURE GUIDANCE IN THE MID/UPPER 60S FOR AFTERNOON HIGHS LOOKS REASONABLE. FOR TONIGHT...SOME LIGHT RAIN MAY SPREAD INTO THE WEST LATE...AHEAD OF ANOTHER WEAK SHORTWAVE TROUGH. EXPECT LOWS IN THE UPPER 30S/MID 40S. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 232 AM CDT THU APR 2 2015 AN ACTIVE WEATHER PATTERN FOR THE LONG TERM IS THE MAIN FORECAST CONCERN. THE BEGINNING OF THE PERIOD SEES ONE SYSTEM WITH NUMEROUS FORECAST ISSUES MOVING OUT OF THE AREA...FOLLOWED BY A FEW QUICK SYSTEMS...THEN AN ACTIVE WEEK NEXT WEEK WITH NUMEROUS SYSTEMS AND CHANCES FOR RAIN. LIKE ADVERTISED LAST NIGHT IN THE AFD...A COLD FRONT STALLS OUT TO OUR SOUTH AS THE MAIN FORCING MOVES QUICKLY TO THE EAST. AT THE SAME TIME ANOTHER WAVE IS MOVING ACROSS THE CENTRAL UNITED STATES. THIS WAVE INTERACTS WITH THE SURFACE FRONT...BRINGING IT SLIGHTLY NORTH AND THEN INDUCING SURFACE CYCLOGENESIS AND MOVING THE FRONT OUT OF THE AREA. THE GEM AND THE GFS ARE THE TWO MODELS WITH THE MOST PRECIP NORTH INTO OUR AREA. WHILE TEMPERATURES WILL BE WELL ABOVE FREEZING...THE SREF MEAN SUGGESTS THAT THE TEMPS IN EARLY AFTERNOON WILL BE CONDUCIVE TO SNOWFALL. THE REST OF THE DETERMINISTIC MODELS HAVE US ABOVE FREEZING. THE OPERATIONAL NAM...A MEMBER OF THE SREF...HAS NO QPF FOR US DURING THIS TIME. SO THERE IS A LARGE SPREAD IN THE MEMBERS IN THE SREF. THINK THE SREF MEAN IS BEING SWAYED HEAVILY BY ONE MEMBER...SO DONT THINK WE WILL SEE SNOW. FRIDAY EVENING THROUGH SUNDAY AFTERNOON LOOKS TO BE DRY FOR OUR AREA. ANOTHER CLIPPER MOVES THROUGH WISCONSIN. LATEST RUNS BRING THE QPF WITH THIS SYSTEM FURTHER NORTH...SO ONLY OUR FAR NORTHERN ZONES HAVE A SLIGHT CHANCE FOR POPS. WITH THE THERMAL PROFILE IT APPEARS THAT RASN MIX WOULD BE PREFERRED FOR ANY PRECIP THAT FALLS. MONDAY THROUGH TUESDAY EVENING...AN ACTIVE PATTERN SETS UP OVER THE AREA AND IT LOOKS LIKE WE SEE QPF THROUGH THE PERIOD. MODELS ARE IN AGREEMENT IN THE OVERALL LARGE SCALE PATTERN...HOWEVER THE FINESCALE FEATURES ARE YET TO BE AGREED UPON. IT LOOKS LIKE THE BEST CHANCE FOR THUNDER AT THIS TIME WILL BE MONDAY AFTERNOON THROUGH THE NIGHT. WEDNESDAY AND THURSDAY...THE MODELS HAVE FLIP FLOPPED ON LARGE SCALE FEATURES AND ARE DIFFERENT IN SOLUTIONS WITH THE ECMWF BEING WET AND THE GFS BEING DRY. OBVIOUSLY AS WE GET CLOSER THIS WILL BE THE NEXT FORECAST CONCERN BY EARLY NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 711 AM CDT THU APR 2 2015 PERIODS OF MVFR CIGS/VSBYS IN SHOWERS WILL END QUICKLY FROM WEST TO EAST THIS MORNING...FOLLOWED BY PARTIAL CLEARING AND A GUSTY NORTHWEST WIND WHICH WILL DIMINISH UNDER 10 KTS BY LATE AFTERNOON. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...RP KINNEY SYNOPSIS...RP KINNEY SHORT TERM...RP KINNEY LONG TERM...GIBBS AVIATION...RP KINNEY
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
542 AM CDT THU APR 2 2015 .UPDATE... ISSUED AT 534 AM CDT THU APR 2 2015 UPDATE FOR MINOR CHANGES TO POPS AND RAINFALL AMOUNTS. ALSO SCALED THUNDER MENTION BACK TO ISOLATED. RAIN COVERAGE HAS INCREASED SOMEWHAT OVER THE PAST COUPLE OF HOURS. INTENSITY HAS PICKED UP ACROSS THE SOUTH WITH INCREASED FORCING FROM APPROACHING SHORTWAVE...WHILE THE STORMS IN THE FAR EAST LOOK TO BE FUELED BY THE NOSE OF A NEAR 50 KT LOW LEVEL JET. RAIN STILL ON TRACK TO MOVE EAST OF THE FORECAST AREA AROUND MIDDAY. && .SYNOPSIS... ISSUED AT 232 AM CDT THU APR 2 2015 AT 300 AM CDT...A COLD FRONT HAD PUSHED INTO CENTRAL IOWA. MORE FAVORABLE MOISTURE AHEAD OF THE BOUNDARY HAD FINALLY MADE IT INTO EASTERN IOWA...WITH DEWPOINTS IN THE LOW/MID 50S. SHOWERS/SCATTERED THUNDERSTORMS ALONG AND EAST OF THE FRONT WERE MOVING INTO THE FAR WESTERN FRINGE OF THE FORECAST AREA...FUELED BY A RIBBON OF MU CAPE AOA 500 J/KG AND A SWATH OF STEEPER MID LEVEL LAPSE RATE. A SHORT WAVE TROUGH LIFTING THROUGH ILLINOIS IS SUPPORTING ISOLATED CONVECTION ACROSS THE FAR EASTERN COUNTIES. EARLY MORNING TEMPERATURES WERE IN THE 50S TO LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 232 AM CDT THU APR 2 2015 THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS PRECIP TRENDS/COVERAGE/AMOUNTS THROUGH EARLY AFTERNOON. IN THE NEAR TERM...HIGH RESOLUTION MODELS INCLUDING THE HRRR AND ARW/NMM ARE RUNNING A BIT SLOW BUT OTHERWISE HAVE THE CURRENT WEATHER MODELED WELL. HAVE ADJUSTED POPS FOR NEAR TERM TRENDS. HIGHEST QPF THROUGH 12Z WILL BE FOCUSED ACROSS THE WEST AND THE FAR EASTERN FRINGE...WITH SPOTTIER RAIN COVERAGE CENTRAL. AFTER 12Z...HIGHEST QPF AND SHOWER/STORM COVERAGE SHOULD BE LOCATED ALONG/EAST OF THE MISSISSIPPI RIVER AS THE UPSTREAM SHORTWAVE INTERACTS WITH THE COLD FRONT. TOTAL QPF NOW LOOKS LIKE IT WILL FALL MAINLY IN THE TENTH TO THIRD OF AN INCH RANGE. THE CHANCE OF ANY SEVERE WEATHER IS VIRTUALLY NIL. RAIN WILL END IN THE SOUTHEAST/EAST DURING THE EARLY AFTERNOON. BLENDED TEMPERATURE GUIDANCE IN THE MID/UPPER 60S FOR AFTERNOON HIGHS LOOKS REASONABLE. FOR TONIGHT...SOME LIGHT RAIN MAY SPREAD INTO THE WEST LATE...AHEAD OF ANOTHER WEAK SHORTWAVE TROUGH. EXPECT LOWS IN THE UPPER 30S/MID 40S. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 232 AM CDT THU APR 2 2015 AN ACTIVE WEATHER PATTERN FOR THE LONG TERM IS THE MAIN FORECAST CONCERN. THE BEGINNING OF THE PERIOD SEES ONE SYSTEM WITH NUMEROUS FORECAST ISSUES MOVING OUT OF THE AREA...FOLLOWED BY A FEW QUICK SYSTEMS...THEN AN ACTIVE WEEK NEXT WEEK WITH NUMEROUS SYSTEMS AND CHANCES FOR RAIN. LIKE ADVERTISED LAST NIGHT IN THE AFD...A COLD FRONT STALLS OUT TO OUR SOUTH AS THE MAIN FORCING MOVES QUICKLY TO THE EAST. AT THE SAME TIME ANOTHER WAVE IS MOVING ACROSS THE CENTRAL UNITED STATES. THIS WAVE INTERACTS WITH THE SURFACE FRONT...BRINGING IT SLIGHTLY NORTH AND THEN INDUCING SURFACE CYCLOGENESIS AND MOVING THE FRONT OUT OF THE AREA. THE GEM AND THE GFS ARE THE TWO MODELS WITH THE MOST PRECIP NORTH INTO OUR AREA. WHILE TEMPERATURES WILL BE WELL ABOVE FREEZING...THE SREF MEAN SUGGESTS THAT THE TEMPS IN EARLY AFTERNOON WILL BE CONDUCIVE TO SNOWFALL. THE REST OF THE DETERMINISTIC MODELS HAVE US ABOVE FREEZING. THE OPERATIONAL NAM...A MEMBER OF THE SREF...HAS NO QPF FOR US DURING THIS TIME. SO THERE IS A LARGE SPREAD IN THE MEMBERS IN THE SREF. THINK THE SREF MEAN IS BEING SWAYED HEAVILY BY ONE MEMBER...SO DONT THINK WE WILL SEE SNOW. FRIDAY EVENING THROUGH SUNDAY AFTERNOON LOOKS TO BE DRY FOR OUR AREA. ANOTHER CLIPPER MOVES THROUGH WISCONSIN. LATEST RUNS BRING THE QPF WITH THIS SYSTEM FURTHER NORTH...SO ONLY OUR FAR NORTHERN ZONES HAVE A SLIGHT CHANCE FOR POPS. WITH THE THERMAL PROFILE IT APPEARS THAT RASN MIX WOULD BE PREFERRED FOR ANY PRECIP THAT FALLS. MONDAY THROUGH TUESDAY EVENING...AN ACTIVE PATTERN SETS UP OVER THE AREA AND IT LOOKS LIKE WE SEE QPF THROUGH THE PERIOD. MODELS ARE IN AGREEMENT IN THE OVERALL LARGE SCALE PATTERN...HOWEVER THE FINESCALE FEATURES ARE YET TO BE AGREED UPON. IT LOOKS LIKE THE BEST CHANCE FOR THUNDER AT THIS TIME WILL BE MONDAY AFTERNOON THROUGH THE NIGHT. WEDNESDAY AND THURSDAY...THE MODELS HAVE FLIP FLOPPED ON LARGE SCALE FEATURES AND ARE DIFFERENT IN SOLUTIONS WITH THE ECMWF BEING WET AND THE GFS BEING DRY. OBVIOUSLY AS WE GET CLOSER THIS WILL BE THE NEXT FORECAST CONCERN BY EARLY NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1152 PM CDT WED APR 1 2015 COLD FRONT AND LINE OF SHOWERS AND THUNDERSTORMS MOVING INTO CENTRAL IA LATE TONIGHT WILL ADVANCE THROUGH THE TERMINALS LATE TONIGHT INTO THE EARLY MORNING HOURS THURSDAY. AHEAD OF THE FRONT...GUSTY SOUTH WINDS WILL CONTINUE AT THE SURFACE. NEARBY MDCRS AIRCRAFT SOUNDINGS AND RADAR VAD WIND PROFILES INDICATED STRONGER WINDS JUST OFF THE DECK...GOING FROM AROUND 15 KTS AT THE SURFACE TO AS HIGH AS 40 TO 50 KTS AROUND 1500 FT AGL. AT THIS TIME...THERE DOES NOT APPEAR TO BE SIGNIFICANT DIRECTIONAL SHEAR OR SHARP VERTICAL SHEAR TO INCLUDE LLWS IN THE TAFS. THE ADVANCING SHOWERS AND ISOLATED THUNDERSTORMS WILL LIKELY RESULT IN A SEVERAL HOUR WINDOW OF MVFR CONDITIONS THU MORNING... AND WILL CONTINUE TO KEEP CIGS HIGHER THAN WHAT THE TOO MOIST MODEL GUIDANCE DEPICTS. SHOWERS ARE EXPECTED TO CLEAR ALL SITES BY LATE MORNING WITH WINDS VEERING TO THE NORTHWEST AND CONDITIONS BECOMING VFR...WHICH WILL DOMINATE THROUGH THE REST OF THE DAY. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...RP KINNEY SYNOPSIS...RP KINNEY SHORT TERM...RP KINNEY LONG TERM...GIBBS AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1013 AM EDT THU APR 2 2015 .UPDATE... ISSUED AT 1013 AM EDT THU APR 2 2015 HAVE UPDATED NDFD AND ASSOCIATED PRODUCTS BASED ON LATEST RADAR...SATELLITE AND OBSERVATIONAL TRENDS. BASED ON TRENDS AND SUPPORT FROM THE LATEST HRRR HAVE LOW RAIN CHANCES NEXT FEW HOURS WITH INCREASING TREND INTO THE AFTERNOON. WILL BE EXAMINING THE FLASH FLOOD THREAT FOR TONIGHT INTO FRIDAY...AND MAKE DETERMINATION ON A FLASH FLOOD WATCH EARLY THIS AFTERNOON. THE WPC DAY 1 EXCESSIVE RAINFALL OUTLOOK HAS BEEN UPDATED TO INCLUDE THE ENTIRE FORECAST AREA FOR THE PERIOD THROUGH 12Z FRIDAY. UPDATE ISSUED AT 816 AM EDT THU APR 2 2015 SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER OUR WESTERN COUNTIES EARLY THIS MORNING. OUR FAR NW COUNTIES SHOULD BE IMPACTED THE MOST. HAVE MADE MINOR ADJUSTMENTS FOR OBSERVED CONDITIONS. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 400 AM EDT THU APR 2 2015 DESPITE VERY DRY AIR LINGERING ALOFT OVER THE REGION...A WET AND STORMY PERIOD IS IN STORE. AT 3 AM RIDGETOPS STILL HAD DEW POINTS IN THE TEENS AND RELATIVE HUMIDITY IN THE 20S. HOWEVER...GULF OF MEXICO MOISTURE WAS ON THE WAY IN. SURFACE DEW POINTS WERE NEAR 60 FROM NORTHERN ALABAMA TO WESTERN KENTUCKY...WITH THUNDERSTORMS ONGOING OVER WESTERN KENTUCKY. THIS MOISTURE WILL QUICKLY ADVECTED INTO OUR AREA TODAY. AS THE SHORTWAVE TROUGH CAUSING CONVECTION IN WESTERN KENTUCKY MOVES EAST TODAY...PRECIP WILL DEVELOP. IT WILL INITIALLY BATTLE LOW LEVEL DOWNSLOPE FLOW AND DRY AIR OVER OUR AREA...AND ONLY CHANCE CATEGORY POPS HAVE BEEN USED TODAY FOR MOST LOCATIONS. OUR FAR NW COUNTIES WILL HAVE THE BEST UPPER LEVEL SUPPORT AND WILL BE OUTSIDE OF THE DOWNSLOPE INFLUENCE...AND LIKELY POPS HAVE BEEN PLACED THERE. LOW LEVEL FLOW WILL BECOME MORE SOUTHWESTERLY TONIGHT AND DOWNSLOPE INFLUENCE WILL BE LOST. A COLD FRONT WILL APPROACH FROM THE NORTHWEST AND PROVIDE A FOCUS FOR MORE PRECIP. THE HIGHEST POPS WILL BE IN OUR NORTHWEST COUNTIES...BUT ALL AREAS WILL HAVE A HIGHER POP. HOWEVER...THE BEST SUPPORT FOR PRECIP WILL BE IN OUR NORTHERN COUNTIES AS A COLD FRONT APPROACHES FROM THE NORTHWEST. THE FRONT WILL STALL NEAR THE OHIO RIVER ON FRIDAY...AND THEN GET A PUSH SOUTHEAST THROUGH THE JKL FORECAST AREA ON FRIDAY NIGHT AS AN UPPER TROUGH PROMPTS A LOW PRESSURE WAVE TO TRAVEL ALONG THE FRONT. AT THIS POINT...THE AXIS OF HEAVIEST PRECIP LOOKS LIKE IT WILL BE JUST TO OUR NORTH DUE TO THE POSITION OF THE STALLED FRONT. THIS WILL NEED TO BE WATCHED...SINCE A SLIGHT SOUTHWARD SHIFT WOULD MEAN HEAVIER PRECIP FOR OUR NORTHERN COUNTIES AND A GREATER THREAT OF FLOODING. FOR THE TIME BEING...HAVE HELD OFF ON A FLOOD WATCH. PLENTY OF SHEAR WILL BE AVAILABLE TO SUPPORT ORGANIZED CONVECTION DURING THIS EVENT...AND SEVERE STORMS CAN NOT BE RULED OUT. HOWEVER...THE GREATEST INSTABILITY IS EXPECTED TO BE TO OUR WEST AND SOUTHWEST IN THE AREA OF HIGHER LOW-LEVEL THETA E...AND THE GREATEST RISK OF SEVERE WEATHER SHOULD BE THERE. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 400 AM EDT THU APR 2 2015 THE LONG TERM PERIOD STARTS AS ANY REMAINING CONVECTION...RAIN...AND COLD FRONT PUSH THROUGH OUR AREA. THE MODELS ARE IN GOOD AGREEMENT WITH THE TIMING OF THE FRONTAL PASSAGE WHICH IS BETWEEN 00Z AND 06Z SATURDAY FOR THE EASTERN MOST PORTION OF KENTUCKY. COOLER...DRIER AIR WILL THEN QUICKLY MOVE IN DURING THE DAY ON SATURDAY...WITH THE EXCEPTION OF SOME UPSLOPE SHOWERS POSSIBLY LASTING INTO THE EARLY AFTERNOON HOURS. ALL IN ALL...SATURDAY AND SUNDAY WILL BE QUITE PLEASANT WITH SUNNY SKIES AND TEMPS REACHING THE MID 50S AND MID 60S RESPECTIVELY. ON MONDAY...THE UPPER LEVELS TURN MORE WESTERLY TO SOUTHWESTERLY AHEAD OF A DIGGING TROUGH ACROSS THE WESTERN U.S.. AT THE SURFACE...SOUTHERLY FLOW WILL PULL IN WARM...MOIST AIR FROM THE GULF. ADDITIONALLY...BOTH THE GFS AND ECMWF INDICATE A SERIES OF DISTURBANCES THAT WILL TRACK ACROSS THE REGION...INCREASING THE CHANCES FOR RAIN AND THUNDERSTORMS AT TIMES FROM MONDAY MORNING THROUGH THE END OF THE PERIOD. BEST INSTABILITY LOOKS TO BE LATE MONDAY THROUGH EARLY WEDNESDAY PER LATEST MODEL SOUNDINGS. IN FACT... CAPE AND LI/S LOOK JUST AS IMPRESSIVE AS IT DOES IN THE SHORT TERM. HOWEVER...IT IS TOO FAR OUT TO WORK OUT THE DETAILS GIVEN MODEL DIFFERENCES. SO HAVE WENT WITH THE SUPERBLEND FOR POPS AND HAVE ALSO INCLUDED THUNDER IN THE WX GRIDS DURING THIS TIME FRAME. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 816 AM EDT THU APR 2 2015 MAINLY VFR CONDITIONS PREVAILED AT THE START OF THE PERIOD. ALTHOUGH SHOWERS AND THUNDERSTORMS WERE LIKELY BRINGING LOCALIZED MVFR OR WORSE IN A CORRIDOR FROM SOMERSET TO MOREHEAD. ADDITIONAL SHOWERS AND THUNDERSTORMS WILL OCCUR TODAY AND BRING LOCALIZED SUB-VFR. LOW CONFIDENCE IN TIMING/LOCATION PRECLUDES USING ANYTHING MORE THAN VCSH IN MOST TAFS. A LULL IN PRECIP IS EXPECTED LATE IN THE DAY AND INTO THE EVENING...WITH ADDITION PRECIP MOVING IN FROM THE NW LATE TONIGHT. WINDS WILL PICK UP OUT OF THE S AND SW DURING THE MORNING...WITH SOME GUSTS AROUND 20KTS IN THE AFTERNOON. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SBH SHORT TERM...HAL LONG TERM...JVM AVIATION...HAL
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
932 AM EDT THU APR 2 2015 .SYNOPSIS... SHOWER CHANCES ARE EXPECTED TO INCREASE TODAY THROUGH FRIDAY NIGHT AS A COLD FRONT SLOWLY TRACKS ACROSS THE AREA. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATES MADE THIS MORNING WERE MAINLY TO ADJUST POPS EARLY ON BASED ON CURRENT RADAR AS A LINE OF SHOWERS AND STORMS APPROACHES ALONG THE WARM FRONT. THIS LINE WILL HAVE TO OVERCOME VERY DRY AIR AT THE SURFACE BASED ON THE SURFACE OBS AND SOUNDING...SO NOT EXPECTED MUCH RAINFALL INITIALLY. ALSO...ADJUSTED DIURNAL TEMPERATURES AND DEWPOINTS BASED ON CURRENT OBS AS STRONG WARM ADVECTION IS ALREADY BRINGING TEMPERATURES INTO THE 50`S. PREVIOUS...THE FIRST ROUND OF SHOWERS ARE EXPECTED TODAY IN WARM ADVECTION AND WITH LOW LEVEL JET DEVELOPMENT...AND CONTINUED INCREASING POPS TO LIKELY FROM W-E. PROGGED INSTABILITY IS LIMITED...BUT DID MAINTAIN ISOLATED THUNDER MAINLY W OF PIT. MIXING SHOULD ALLOW FOR SOME GUSTY SOUTHWEST WINDS BY AFTERNOON. WITH A QUICK ONSET OF CLOUDS AND SHOWERS...HIGH TEMPERATURES SHOULD BE HELD MAINLY IN THE 60S TO NEAR 70 USING THE LATEST SREF AND LAMP NUMBERS. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/... THE COLD FRONT IS PROGGED TO DROP S ACROSS THE REGION TONIGHT... STALLING OUT FROM SW OH INTO SOUTHERN PA. CONTINUED CATEGORICAL POPS FOR SHOWERS...AND AN ISOLATED THUNDER MENTION FOR MUCH OF THE AREA AS SHOWALTER INDICIES DROP BELOW ZERO WITH ELEVATED INSTABILITY AND A PERSISTENT LOW LEVEL JET. A SURFACE WAVE IS PROGGED TO TRACK ALONG THE FRONT FROM THE MS VALLEY INTO THE OH VALLEY FRIDAY BRINGING ADDITIONAL SHOWERS TO THE AREA. ISOLATED THUNDERSTORMS ARE POSSIBLE S OF PIT AGAIN IN LIMITED INSTABILITY. THE MAIN UPPER TROUGH AXIS IS PROGGED TO CROSS THE AREA LATE FRIDAY NIGHT AND EARLY SATURDAY AS THE SURFACE LOW CONTINUES STRENGTHENING AS IT MOVES OFF THE NEW ENGLAND COAST. THIS SHOULD BRING A RAPID END TO ANY PRECIP...THOUGH A BRIEF PERIOD OF SNOW SHOWERS IS POSSIBLE AS IT ENDS. TOTAL RAINFALL AMOUNTS OF 1.25 TO 2 INCHES ARE EXPECTED THROUGH FRIDAY EVENING. THIS WILL LIKELY CAUSE RISES ON AREA RIVERS...THOUGH SIGNIFICANT HYDRO PROBLEMS ARE NOT EXPECTED AT THIS TIME. PREFERRED A BLEND OF THE GFS/ECMWF...MAINLY DUE TO THEIR HANDLING OF THE FRONTAL SURFACE WAVE...AND THE MORE REASONABLE QPF NUMBERS FROM THE ECMWF. AFTER BUILDING HIGH PRESSURE LATER SATURDAY...A WEAK SHORTWAVE IS PROGGED TO BRUSH AREAS NORTH OF I 80 WITH LOW PRECIP CHANCES ON SUNDAY. ABOVE AVERAGE TEMPS FRIDAY ARE EXPECTED TO BE REPLACED BY WELL BELOW AVERAGE READINGS SATURDAY...WITH SOME RECOVERY FOR SUNDAY. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... NEXT WEEK TEMPERATURES ARE FORECAST TO MODERATE TO NEAR...THEN ABOVE THE SEASONAL AVERAGES AS A SHORTWAVE RIDGE DEVELOPS OVER THE EASTERN HALF OF THE CONUS IN RESPONSE TO WESTERN STATES TROUGHING. PRECIP CHANCES WILL RISE AS THE WEEK AND TROUGH PROGRESS. THE LONG TERM PROGNOSIS WAS PRIMARILY BASED ON ADJUSTED WPC GUIDANCE. && .AVIATION /13Z THURSDAY THROUGH MONDAY/... LINE OF SHOWERS AND STORMS ALONG THE WARM FRONT WILL CROSS A FEW OF THE TAF SITES THROUGH MIDDAY. AT THIS POINT...HAVE ADDED VCTS TO ZZV AND WILL FURTHER AMEND AS NEEDED IF LINE HOLDS TOGETHER. THE HRRR HAS BEEN HANDLING THIS THE BEST SO TIMING WAS MAINTAINED OFF OF GUIDANCE AND RADAR TRENDS. HOWEVER...RESTRICTIONS SHOULD BE LIMITED TO PORTS WHERE A THUNDERSTORM PASSES AND GENERAL VFR IS MAINTAINED UNTIL MORE WIDESPREAD PRECIITATION IS EXPECTED LATE THIS AFTERNOON. INTENSIFYING LOW LEVEL JET AND WARM ADVECTION WILL MAINTAIN A THREAT FOR WIND SHEAR UNTIL BETTER MIXING THIS AFTERNOON. IT WILL ONCE AGAIN BE AN ISSUE TONIGHT AS WELL...AND WILL BE REINTRODUCED IN THE NEXT TAF ISSUANCE. DEGRADATION TO WIDESPREAD MVFR...AND PROBABLY EVENTUAL IFR...CAN BE EXPECTED AS RAIN BECOMES MORE WIDESPREAD WITH THE ENCROACHING FRONT OVERNIGHT. .OUTLOOK.../FRIDAY THROUGH MONDAY/... LOW PRESSURE MOVING ALONG THE AFOREMENTIONED FRONTAL BOUNDARY WILL MAINTAIN RESTRICTIONS INTO SATURDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1145 AM EDT THU APR 2 2015 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS EXPECTED TODAY WITH PERHAPS SOME RUMBLES OF THUNDER. MODERATE TO BRIEF HEAVY RAINFALL...ALONG WITH GUSTY WINDS CANNOT BE RULED OUT INTO THE AFTERNOON AS A COLD FRONT SWEEPS THROUGH THE REGION...BUT SEVERE WEATHER IS NOT EXPECTED. MUCH COOLER WEATHER MOVES IN TONIGHT INTO THE WEEKEND...AND ACTIVE WEATHER IS EXPECTED TO CONTINUE. RAIN CHANCES RETURN FRIDAY AFTERNOON ACROSS SOUTHERN LOWER MICHIGAN WITH A CHANCE FOR A RAIN/SNOW MIX FRIDAY NIGHT. FREQUENT BOUTS OF PRECIPITATION ARE EXPECTED SUNDAY INTO THE MIDDLE OF NEXT WEEK. && .UPDATE... ISSUED AT 1145 AM EDT THU APR 2 2015 NO CHANGES TO THE GOING FORECAST ALTHOUGH IT APPEARS THE RISK OF THUNDER MAY BE DWINDLING. THE INITIAL WARM ADVECTION SURGE TOUCHED OFF A FEW TSTMS EARLIER THIS MORNING BUT LATEST TSTM ACTIVITY IS CURRENTLY FAVORING THE BETTER INSTABILITY SOUTH OF THE MI BORDER. THE MAIN CHANCE OF A FEW RUMBLES SHOULD BE SOUTH AND EAST OF GRR THROUGH 21Z WHERE NEAR ZERO TO SLIGHTLY NEGATIVE H8-H5 THETA-E LAPSE RATES EXIST. DESPITE THE LIMITED THUNDER THREAT... OVERALL COVERAGE OF RAIN SHOWERS IS EXPECTED TO INCREASE OVER THE NEXT COUPLE HOURS AS THE FRONT COMES THROUGH. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS WITH PERHAPS A RUMBLE OF THUNDER TODAY FOLLOWED BY MUCH COOLER WEATHER FRIDAY AND SATURDAY. A DRY VERTICAL PROFILE IS NOTED ON A 05Z RAP SOUNDING...BUT HEALTHY MID LEVEL MOISTURE ADVECTION WILL OCCUR FROM THIS WRITING THROUGH THE NEXT SEVERAL HOURS. H925 TO H850 LAYER WAA IS ALSO ONGOING DURING THIS TIMEFRAME WITH STRONG SOUTHWESTERLY FLOW AHEAD OF THE H850 THERMAL TROUGH. AT THE LOW LEVELS...MUCH HIGHER THETA E AIR ADVECTS IN AFTER 12Z THIS MORNING JUST AHEAD OF THE SURFACE COLD FRONT. DEWPOINTS IN THE LOWER 50S ARE EXPECTED THIS AFTERNOON ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. A WEAK SHORTWAVE NOTED OVER WESTERN IL ON WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NORTHEAST INTO OUR AREA BUT LOSE SOME OF ITS PUNCH. NEVERTHELESS...WEAK ELEVATED INSTABILITY IS PRESENT AT THE TIME OF ITS ARRIVAL AROUND 12Z. RAIN CHANCES...WITH PERHAPS A RUMBLE OF THUNDER...INCREASE AFTER 11Z. THE COLD FRONT TRACKS THROUGH THE CWA BETWEEN 16-22Z. DIURNAL HEATING JUST PRIOR TO THIS FRONTAL PASSAGE WILL GIVE MOST AREAS THEIR BEST CHANCE FOR THUNDER AND ASSOCIATED NON-SEVERE THREATS...SUCH AS MODERATE TO BRIEF HEAVY RAIN...GUSTY WINDS...AND LIGHTNING. INSTABILITY IS MARGINAL AT BEST...BUT HIGHEST SOUTH OF I-96. 0-6 KM BULK SHEAR INCREASES THROUGHOUT THE DAY...WITH VALUES OF AROUND 35-45 KNOTS SOUTH OF I-96 AT 18Z. BOTTOM LINE...RAIN SHOWERS WITH A CHANCE OF THUNDER INTO THE AFTERNOON. BEHIND THE FRONT...DRY WEATHER EXPECTED TONIGHT WITH LOWS IN THE 30S TO AROUND 40 DEGREES. ANOTHER PV ANOMALY AND SHORTWAVE MOVE INTO THE AREA TOMORROW...SUPPORTING MAINLY A CHANCE OF RAIN ACROSS THE SOUTHERN FORECAST AREA FRIDAY AFTERNOON AND A MIX OF RAIN AND SNOW FRIDAY NIGHT. LOWER MI IS IN A FAVORABLE POSITION WITHIN A COUPLED UPPER JET STRUCTURE DURING THIS TIMEFRAME...MEANING GOOD UPPER DIVERGENCE IS RESPONSIBLE FOR STRENGTHENING OF THE MIDLEVEL SHORTWAVE. LOWS FRIDAY NIGHT ARE EXPECTED TO PLUMMET INTO THE UPPER TEENS AND 20S. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM EDT THU APR 2 2015 LOOKS LIKE AN ACTIVE STORM TRACK SETTING UP IN THE EXTENDED PERIOD WITH FREQUENT BOUTS OF PRECIPITATION...INCLUDING SOME SNOW AT TIMES. A PLAINS LOW MOVES EAST TOWARDS THE GREAT LAKES SATURDAY NIGHT AND ISENTROPIC ASCENT OUT AHEAD OF IT SHOULD RESULT IN SOME LIGHT SNOW AND RAIN SATURDAY NIGHT. IT TAKES UNTIL MONDAY AFTERNOON BEFORE THE COLD AIR HAS ERODED ENOUGH TO ALLOW FOR A FORECAST OF ALL RAIN ACROSS THE ENTIRE FORECAST AREA. BEST CHANCE FOR STEADY RAIN WILL BE ON MONDAY NIGHT AS THE SFC WAVE TRACKS ALONG THE FRONT DRAPED ACROSS LOWER MICHIGAN. A SECOND WAVE PROLONGS THE PRECIP INTO TUESDAY NIGHT...AND ENOUGH COLD AIR RETURNS TO BRING THE POSSIBILITY OF A MIX ACROSS THE NORTHERN FORECAST AREA BEFORE THE PRECIP TAPERS OFF ON WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 743 AM EDT THU APR 2 2015 SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING SOME MVFR CONDITIONS THIS MORNING. THE CONDITIONS WILL LOWER TO IFR AFTER 18Z AS LOW CLOUDS AND LIGHT FOG DEVELOP. CONDITIONS WILL IMPROVE TO VFR LATER THIS EVENING AS THE RAIN MOVES OUT. SOUTH WINDS WILL GUSTS TO NEAR 20 KNOTS THROUGH THE AFTERNOON. && .MARINE... ISSUED AT 358 AM EDT THU APR 2 2015 SOUTH WINDS TO 30 KNOTS THIS MORNING WILL VEER SOUTHWESTERLY AT 10 TO 20 KNOTS IN THE AFTERNOON. 3 TO 5 FOOT WAVES TODAY WILL SUBSIDE TO 1 TO 2 FEET THIS EVENING. A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH 2 PM FOR THE NEARSHORE WATERS. PERIODS OF RAIN ARE EXPECTED TODAY ALONG WITH A CHANCE FOR THUNDER AS A COLD FRONT SWEEPS THROUGH. THE RAIN WILL MOVE OUT THIS AFTERNOON. SOUTHWEST WINDS AROUND 10 KNOTS WILL VEER WESTERLY TONIGHT. NORTHERLY WINDS AT 10 TO 20 KNOTS ARE EXPECTED ON FRIDAY...RESULTING IN WAVES BUILDING SOMEWHAT. && .HYDROLOGY... ISSUED AT 1123 AM EDT THU APR 2 2015 LITTLE OR NO RISES ARE BEING NOTED ON AREA RIVERS TODAY AND WITHIN THE NEAR FUTURE. MINOR WITHIN BANK RISES MAY OCCUR AS WE PROGRESS THROUGH THE WEEK. MAINLY LIGHT TO MODERATE RAINFALL IS AFFECTING THE AREA TODAY WITH A FEW POCKETS OF BRIEF HEAVY RAINFALL. THE HEAVIER RAIN HAS BEEN LOCALIZED AND DIRECTLY ASSOCIATED WITH THUNDERSTORMS. THIS IS EXPECTED TO COME TO AN END LATE TODAY BUT THE REMAINDER OF THE WEEK WILL REMAIN RATHER ACTIVE. LIGHT RAIN IS POSSIBLE FRIDAY AND COULD MIX WITH SNOW FRIDAY NIGHT. ANOTHER SYSTEM WILL BRING MORE GENEROUS AMOUNTS OF MOISTURE TO THE AREA BY THE END OF THE WEEKEND AND INTO EARLY NEXT WEEK. NEAR THE END OF THE 7 DAY PERIOD...YET ANOTHER WAVE OF MOISTURE MOVES THROUGH. PRECIPITATION TOTALS THROUGH THE NEXT WEEK MAY EXCEED AN INCH THROUGHOUT THE FORECAST AREA. RESPONSE TIMES BETWEEN EPISODES OF PRECIPITATION SHOULD ALLOW FOR ONLY MINOR RISES TO OCCUR. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>849. && $$ UPDATE...MEADE SYNOPSIS...EBW SHORT TERM...EBW LONG TERM...OSTUNO AVIATION...OSTUNO HYDROLOGY...JAM MARINE...EBW
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1123 AM EDT THU APR 2 2015 LATEST UPDATE... HYDRO .SYNOPSIS... ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS EXPECTED TODAY WITH PERHAPS SOME RUMBLES OF THUNDER. MODERATE TO BRIEF HEAVY RAINFALL...ALONG WITH GUSTY WINDS CANNOT BE RULED OUT INTO THE AFTERNOON AS A COLD FRONT SWEEPS THROUGH THE REGION...BUT SEVERE WEATHER IS NOT EXPECTED. MUCH COOLER WEATHER MOVES IN TONIGHT INTO THE WEEKEND...AND ACTIVE WEATHER IS EXPECTED TO CONTINUE. RAIN CHANCES RETURN FRIDAY AFTERNOON ACROSS SOUTHERN LOWER MICHIGAN WITH A CHANCE FOR A RAIN/SNOW MIX FRIDAY NIGHT. FREQUENT BOUTS OF PRECIPITATION ARE EXPECTED SUNDAY INTO THE MIDDLE OF NEXT WEEK. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS WITH PERHAPS A RUMBLE OF THUNDER TODAY FOLLOWED BY MUCH COOLER WEATHER FRIDAY AND SATURDAY. A DRY VERTICAL PROFILE IS NOTED ON A 05Z RAP SOUNDING...BUT HEALTHY MID LEVEL MOISTURE ADVECTION WILL OCCUR FROM THIS WRITING THROUGH THE NEXT SEVERAL HOURS. H925 TO H850 LAYER WAA IS ALSO ONGOING DURING THIS TIMEFRAME WITH STRONG SOUTHWESTERLY FLOW AHEAD OF THE H850 THERMAL TROUGH. AT THE LOW LEVELS...MUCH HIGHER THETA E AIR ADVECTS IN AFTER 12Z THIS MORNING JUST AHEAD OF THE SURFACE COLD FRONT. DEWPOINTS IN THE LOWER 50S ARE EXPECTED THIS AFTERNOON ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. A WEAK SHORTWAVE NOTED OVER WESTERN IL ON WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NORTHEAST INTO OUR AREA BUT LOSE SOME OF ITS PUNCH. NEVERTHELESS...WEAK ELEVATED INSTABILITY IS PRESENT AT THE TIME OF ITS ARRIVAL AROUND 12Z. RAIN CHANCES...WITH PERHAPS A RUMBLE OF THUNDER...INCREASE AFTER 11Z. THE COLD FRONT TRACKS THROUGH THE CWA BETWEEN 16-22Z. DIURNAL HEATING JUST PRIOR TO THIS FRONTAL PASSAGE WILL GIVE MOST AREAS THEIR BEST CHANCE FOR THUNDER AND ASSOCIATED NON-SEVERE THREATS...SUCH AS MODERATE TO BRIEF HEAVY RAIN...GUSTY WINDS...AND LIGHTNING. INSTABILITY IS MARGINAL AT BEST...BUT HIGHEST SOUTH OF I-96. 0-6 KM BULK SHEAR INCREASES THROUGHOUT THE DAY...WITH VALUES OF AROUND 35-45 KNOTS SOUTH OF I-96 AT 18Z. BOTTOM LINE...RAIN SHOWERS WITH A CHANCE OF THUNDER INTO THE AFTERNOON. BEHIND THE FRONT...DRY WEATHER EXPECTED TONIGHT WITH LOWS IN THE 30S TO AROUND 40 DEGREES. ANOTHER PV ANOMALY AND SHORTWAVE MOVE INTO THE AREA TOMORROW...SUPPORTING MAINLY A CHANCE OF RAIN ACROSS THE SOUTHERN FORECAST AREA FRIDAY AFTERNOON AND A MIX OF RAIN AND SNOW FRIDAY NIGHT. LOWER MI IS IN A FAVORABLE POSITION WITHIN A COUPLED UPPER JET STRUCTURE DURING THIS TIMEFRAME...MEANING GOOD UPPER DIVERGENCE IS RESPONSIBLE FOR STRENGTHENING OF THE MIDLEVEL SHORTWAVE. LOWS FRIDAY NIGHT ARE EXPECTED TO PLUMMET INTO THE UPPER TEENS AND 20S. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM EDT THU APR 2 2015 LOOKS LIKE AN ACTIVE STORM TRACK SETTING UP IN THE EXTENDED PERIOD WITH FREQUENT BOUTS OF PRECIPITATION...INCLUDING SOME SNOW AT TIMES. A PLAINS LOW MOVES EAST TOWARDS THE GREAT LAKES SATURDAY NIGHT AND ISENTROPIC ASCENT OUT AHEAD OF IT SHOULD RESULT IN SOME LIGHT SNOW AND RAIN SATURDAY NIGHT. IT TAKES UNTIL MONDAY AFTERNOON BEFORE THE COLD AIR HAS ERODED ENOUGH TO ALLOW FOR A FORECAST OF ALL RAIN ACROSS THE ENTIRE FORECAST AREA. BEST CHANCE FOR STEADY RAIN WILL BE ON MONDAY NIGHT AS THE SFC WAVE TRACKS ALONG THE FRONT DRAPED ACROSS LOWER MICHIGAN. A SECOND WAVE PROLONGS THE PRECIP INTO TUESDAY NIGHT...AND ENOUGH COLD AIR RETURNS TO BRING THE POSSIBILITY OF A MIX ACROSS THE NORTHERN FORECAST AREA BEFORE THE PRECIP TAPERS OFF ON WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 743 AM EDT THU APR 2 2015 SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING SOME MVFR CONDITIONS THIS MORNING. THE CONDITIONS WILL LOWER TO IFR AFTER 18Z AS LOW CLOUDS AND LIGHT FOG DEVELOP. CONDITIONS WILL IMPROVE TO VFR LATER THIS EVENING AS THE RAIN MOVES OUT. SOUTH WINDS WILL GUSTS TO NEAR 20 KNOTS THROUGH THE AFTERNOON. && .MARINE... ISSUED AT 358 AM EDT THU APR 2 2015 SOUTH WINDS TO 30 KNOTS THIS MORNING WILL VEER SOUTHWESTERLY AT 10 TO 20 KNOTS IN THE AFTERNOON. 3 TO 5 FOOT WAVES TODAY WILL SUBSIDE TO 1 TO 2 FEET THIS EVENING. A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH 2 PM FOR THE NEARSHORE WATERS. PERIODS OF RAIN ARE EXPECTED TODAY ALONG WITH A CHANCE FOR THUNDER AS A COLD FRONT SWEEPS THROUGH. THE RAIN WILL MOVE OUT THIS AFTERNOON. SOUTHWEST WINDS AROUND 10 KNOTS WILL VEER WESTERLY TONIGHT. NORTHERLY WINDS AT 10 TO 20 KNOTS ARE EXPECTED ON FRIDAY...RESULTING IN WAVES BUILDING SOMEWHAT. && .HYDROLOGY... ISSUED AT 1123 AM EDT THU APR 2 2015 LITTLE OR NO RISES ARE BEING NOTED ON AREA RIVERS TODAY AND WITHIN THE NEAR FUTURE. MINOR WITHIN BANK RISES MAY OCCUR AS WE PROGRESS THROUGH THE WEEK. MAINLY LIGHT TO MODERATE RAINFALL IS AFFECTING THE AREA TODAY WITH A FEW POCKETS OF BRIEF HEAVY RAINFALL. THE HEAVIER RAIN HAS BEEN LOCALIZED AND DIRECTLY ASSOCIATED WITH THUNDERSTORMS. THIS IS EXPECTED TO COME TO AN END LATE TODAY BUT THE REMAINDER OF THE WEEK WILL REMAIN RATHER ACTIVE. LIGHT RAIN IS POSSIBLE FRIDAY AND COULD MIX WITH SNOW FRIDAY NIGHT. ANOTHER SYSTEM WILL BRING MORE GENEROUS AMOUNTS OF MOISTURE TO THE AREA BY THE END OF THE WEEKEND AND INTO EARLY NEXT WEEK. NEAR THE END OF THE 7 DAY PERIOD...YET ANOTHER WAVE OF MOISTURE MOVES THROUGH. PRECIPITATION TOTALS THROUGH THE NEXT WEEK MAY EXCEED AN INCH THROUGHOUT THE FORECAST AREA. RESPONSE TIMES BETWEEN EPISODES OF PRECIPITATION SHOULD ALLOW FOR ONLY MINOR RISES TO OCCUR. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>849. && $$ SYNOPSIS...EBW SHORT TERM...EBW LONG TERM...OSTUNO AVIATION...OSTUNO HYDROLOGY...JAM MARINE...EBW
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
743 AM EDT THU APR 2 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS EXPECTED TODAY WITH PERHAPS SOME RUMBLES OF THUNDER. MODERATE TO BRIEF HEAVY RAINFALL...ALONG WITH GUSTY WINDS CANNOT BE RULED OUT INTO THE AFTERNOON AS A COLD FRONT SWEEPS THROUGH THE REGION...BUT SEVERE WEATHER IS NOT EXPECTED. MUCH COOLER WEATHER MOVES IN TONIGHT INTO THE WEEKEND...AND ACTIVE WEATHER IS EXPECTED TO CONTINUE. RAIN CHANCES RETURN FRIDAY AFTERNOON ACROSS SOUTHERN LOWER MICHIGAN WITH A CHANCE FOR A RAIN/SNOW MIX FRIDAY NIGHT. FREQUENT BOUTS OF PRECIPITATION ARE EXPECTED SUNDAY INTO THE MIDDLE OF NEXT WEEK. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS WITH PERHAPS A RUMBLE OF THUNDER TODAY FOLLOWED BY MUCH COOLER WEATHER FRIDAY AND SATURDAY. A DRY VERTICAL PROFILE IS NOTED ON A 05Z RAP SOUNDING...BUT HEALTHY MID LEVEL MOISTURE ADVECTION WILL OCCUR FROM THIS WRITING THROUGH THE NEXT SEVERAL HOURS. H925 TO H850 LAYER WAA IS ALSO ONGOING DURING THIS TIMEFRAME WITH STRONG SOUTHWESTERLY FLOW AHEAD OF THE H850 THERMAL TROUGH. AT THE LOW LEVELS...MUCH HIGHER THETA E AIR ADVECTS IN AFTER 12Z THIS MORNING JUST AHEAD OF THE SURFACE COLD FRONT. DEWPOINTS IN THE LOWER 50S ARE EXPECTED THIS AFTERNOON ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. A WEAK SHORTWAVE NOTED OVER WESTERN IL ON WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NORTHEAST INTO OUR AREA BUT LOSE SOME OF ITS PUNCH. NEVERTHELESS...WEAK ELEVATED INSTABILITY IS PRESENT AT THE TIME OF ITS ARRIVAL AROUND 12Z. RAIN CHANCES...WITH PERHAPS A RUMBLE OF THUNDER...INCREASE AFTER 11Z. THE COLD FRONT TRACKS THROUGH THE CWA BETWEEN 16-22Z. DIURNAL HEATING JUST PRIOR TO THIS FRONTAL PASSAGE WILL GIVE MOST AREAS THEIR BEST CHANCE FOR THUNDER AND ASSOCIATED NON-SEVERE THREATS...SUCH AS MODERATE TO BRIEF HEAVY RAIN...GUSTY WINDS...AND LIGHTNING. INSTABILITY IS MARGINAL AT BEST...BUT HIGHEST SOUTH OF I-96. 0-6 KM BULK SHEAR INCREASES THROUGHOUT THE DAY...WITH VALUES OF AROUND 35-45 KNOTS SOUTH OF I-96 AT 18Z. BOTTOM LINE...RAIN SHOWERS WITH A CHANCE OF THUNDER INTO THE AFTERNOON. BEHIND THE FRONT...DRY WEATHER EXPECTED TONIGHT WITH LOWS IN THE 30S TO AROUND 40 DEGREES. ANOTHER PV ANOMALY AND SHORTWAVE MOVE INTO THE AREA TOMORROW...SUPPORTING MAINLY A CHANCE OF RAIN ACROSS THE SOUTHERN FORECAST AREA FRIDAY AFTERNOON AND A MIX OF RAIN AND SNOW FRIDAY NIGHT. LOWER MI IS IN A FAVORABLE POSITION WITHIN A COUPLED UPPER JET STRUCTURE DURING THIS TIMEFRAME...MEANING GOOD UPPER DIVERGENCE IS RESPONSIBLE FOR STRENGTHENING OF THE MIDLEVEL SHORTWAVE. LOWS FRIDAY NIGHT ARE EXPECTED TO PLUMMET INTO THE UPPER TEENS AND 20S. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM EDT THU APR 2 2015 LOOKS LIKE AN ACTIVE STORM TRACK SETTING UP IN THE EXTENDED PERIOD WITH FREQUENT BOUTS OF PRECIPITATION...INCLUDING SOME SNOW AT TIMES. A PLAINS LOW MOVES EAST TOWARDS THE GREAT LAKES SATURDAY NIGHT AND ISENTROPIC ASCENT OUT AHEAD OF IT SHOULD RESULT IN SOME LIGHT SNOW AND RAIN SATURDAY NIGHT. IT TAKES UNTIL MONDAY AFTERNOON BEFORE THE COLD AIR HAS ERODED ENOUGH TO ALLOW FOR A FORECAST OF ALL RAIN ACROSS THE ENTIRE FORECAST AREA. BEST CHANCE FOR STEADY RAIN WILL BE ON MONDAY NIGHT AS THE SFC WAVE TRACKS ALONG THE FRONT DRAPED ACROSS LOWER MICHIGAN. A SECOND WAVE PROLONGS THE PRECIP INTO TUESDAY NIGHT...AND ENOUGH COLD AIR RETURNS TO BRING THE POSSIBILITY OF A MIX ACROSS THE NORTHERN FORECAST AREA BEFORE THE PRECIP TAPERS OFF ON WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 743 AM EDT THU APR 2 2015 SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING SOME MVFR CONDITIONS THIS MORNING. THE CONDITIONS WILL LOWER TO IFR AFTER 18Z AS LOW CLOUDS AND LIGHT FOG DEVELOP. CONDITIONS WILL IMPROVE TO VFR LATER THIS EVENING AS THE RAIN MOVES OUT. SOUTH WINDS WILL GUSTS TO NEAR 20 KNOTS THROUGH THE AFTERNOON. && .MARINE... ISSUED AT 358 AM EDT THU APR 2 2015 SOUTH WINDS TO 30 KNOTS THIS MORNING WILL VEER SOUTHWESTERLY AT 10 TO 20 KNOTS IN THE AFTERNOON. 3 TO 5 FOOT WAVES TODAY WILL SUBSIDE TO 1 TO 2 FEET THIS EVENING. A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH 2 PM FOR THE NEARSHORE WATERS. PERIODS OF RAIN ARE EXPECTED TODAY ALONG WITH A CHANCE FOR THUNDER AS A COLD FRONT SWEEPS THROUGH. THE RAIN WILL MOVE OUT THIS AFTERNOON. SOUTHWEST WINDS AROUND 10 KNOTS WILL VEER WESTERLY TONIGHT. NORTHERLY WINDS AT 10 TO 20 KNOTS ARE EXPECTED ON FRIDAY...RESULTING IN WAVES BUILDING SOMEWHAT. && .HYDROLOGY... ISSUED AT 1120 AM EDT TUE MAR 31 2015 RIVERS CONTINUE TO REMAIN WELL BELOW ADVISORY LEVELS WITH ONLY SMALL AND MOMENTARY RESPONSES NOTED FROM RECENT PRECIPITATION. NORTHERN SECTIONS OF THE FORECAST AREA WILL SEE SLOWER RESPONSES DUE TO SNOW MELT WITH LAST NIGHTS SNOWFALL. WE WILL SEE A RATHER ACTIVE PATTERN SET UP THROUGH THE NEXT 7 DAYS. MUCH OF THIS COMES IN TWO WAVES...ONE THURSDAY THEN THE SECOND VERY LATE IN THE WEEKEND AND INTO THE NEXT WORK WEEK. GENERAL AMOUNTS ON TOTAL PRECIPITATION THROUGH THE PERIOD ARE AROUND ONE INCH OR SO. THIS IS FAIRLY EVENLY DIVIDED BETWEEN THE TWO WAVES WHICH SHOULD BE FAVORABLE FOR RESPONSE TIMES. NO FLOODING IS EXPECTED AT THIS TIME. HOWEVER...THE HEAVIER RAIN THAT IS ANTICIPATED TO OUR SOUTH THROUGH THE OHIO VALLEY SHOULD BE WATCHED IN THE EVENT THAT ANY ADJUSTMENTS ARE NEEDED IN PRECIPITATION AMOUNTS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>849. && $$ SYNOPSIS...EBW SHORT TERM...EBW LONG TERM...OSTUNO AVIATION...OSTUNO HYDROLOGY...JAM MARINE...EBW
AREA FORECAST DISCUSSION
NWS JACKSON MS
1022 AM CDT THU APR 2 2015 .UPDATE...SHOWERS AND THUNDERSTORMS ARE WORKING THERE WAY ACROSS THE AREA THIS MORNING...MAINLY NORTH OF I-20 ASSOCIATED WITH A SHORT WAVE. EXPECT THESE THUNDERSTORMS TO CONTINUE TO MOVE NORTHEAST AND EXIT THE AREA BY EARLY AFTERNOON. THE MAIN QUESTION WILL BE WHETHER THE AREA CAN DESTABILIZE ENOUGH FOR MORE SHOWER AND THUNDERSTORM ACTIVITY THIS AFTERNOON. THE NMM/ARW HI-RES MODELS ARE NOT HANDLING THIS MORNING CONVECTION VERY WELL AND ARE NOT DEVELOPING MUCH AFTERNOON ACTIVITY...WHILE THE HRRR TRIES TO DEVELOP MORE ACTIVITY THIS AFTERNOON. FEEL THE ATMOSPHERE WILL STRUGGLE TO DESTABILIZE THIS AFTERNOON...SO WILL JUST KEEP SLIGHT CHANCE THUNDERSTORMS AND RAINSHOWERS IN THE FORECAST FOR THIS AFTERNOON ACROSS MUCH OF THE AREA. THE SHOWERS WILL DISSIPATE QUICKLY AFTER SUNSET. HAVE UPDATED THE FORECAST TO INCREASE POPS FOR AREAS NORTH OF I-20 THIS MORNING. THE REST OF THE FORECAST IS ON TRACK AND THE UPDATES ARE ALREADY OUT./15/ .SHORT TERM...TODAY THROUGH FRIDAY NIGHT...WATER VAPOR IMAGERY THIS MORNING IS SHOWING A SHORTWAVE OVER SE TX MOVING NE TOWARD THE AREA WITH A RATHER EXTENSIVE PLUME OF MOISTURE OVERSPREADING THE AREA. WARM ADVECTION FROM THIS WAVE IS MOST CONCENTRATED ABOVE 305K THETA AND SOME LIGHT SHOWERS HAVE ALREADY BEEN SHOWING UP ON RADAR OVER SW SECTIONS. MAJORITY OF THIS HAS NOT BEEN REACHING THE GROUND WITH WARM/DRY INVERSION LAYER BELOW. AS THE WAVE MOVES EAST/NORTHEAST...EXPECT LIGHT SHOWER ACTIVITY TO CONTINUE THIS MORNING SERVING TO TEMPORARILY WASH AWAY THE LOW LEVEL INVERSION...TAPERING OFF FROM THE SW THIS AFTERNOON. VEERING LOW LEVEL WINDS AS THE WAVE PASSES WILL ALLOW THE LOW LEVEL INVERSION TO QUICKLY REESTABLISH ITSELF OVERNIGHT. MEANWHILE...NEAR ZONAL MID LEVEL FLOW WITH 120 KNOT H3 JET WILL QUICKLY PUSH A RATHER POTENT WAVE OUT OF THE ROCKIES AND INTO THE PLAINS BY DAYS END. SURFACE LOW PRESSURE WILL QUICKLY DEVELOP OVER OK OVERNIGHT AND RACE INTO THE MID MS VALLEY FRIDAY MORNING DRAGGING A FRONT BEHIND. THE AIRMASS OVER THE FORECAST AREA LOOKS TO BE REMAIN CAPPED THROUGH THE MAJORITY OF THE DAY FRIDAY. HOWEVER...DO EXPECT IT TO BREAK DOWN IN THE NEIGHBORHOOD OF THE APPROACHING BOUNDARY AS MOISTURE CONVERGENCE AND FRONTAL FORCING SHOULD BE SUFFICIENT TO ERODE THE WARM LAYER AND ALLOW FOR CONVECTIVE DEVELOPMENT BY LATE AFTERNOON. SEVERE POTENTIAL STILL LOOKS BEST OVER N MS WHERE DEEP LAYER SHEAR WILL EXCEED 50 KNOTS...7-7.5 C/KM H7-H5 LAPSE RATES/25-30 VERTICAL TOTALS...AND DIURNALLY OPTIMIZED SBCAPES AROUND 2000 J/KG WILL EXIST. SEVERE MODE STILL LOOKS PREDOMINANTLY DAMAGING WINDS AND HAIL AS LIMITED LOW LEVEL SHEAR WILL NOT BE SO FAVORABLE FOR TORNADOES. CONVECTIVE LINE WILL MOVE SOUTHEAST ACROSS THE REMAINDER OF THE AREA DURING THE EVENING AND CONTINUING INTO THE FAR SOUTH OVERNIGHT. SEVERE THREAT WILL DIMINISH THE FURTHER SOUTHEAST IT GETS WITH TIME DUE TO THE LOSS OF DAYTIME HEATING./26/ .LONG TERM...SATURDAY THROUGH THURSDAY...COOLER THAN NORMAL TEMPERATURES ARE EXPECTED FOR THE WEEKEND BUT A RETURN TO WARMER THAN NORMAL TEMPERATURES WILL ACCOMPANY THE START OF THE WORK WEEK AND CONTINUE THROUGH THE END OF THE LONG TERM PERIOD. MODEL CONSENSUS HAS THE COLD FRONT SOUTH OF OUR CWA BY SUNRISE SATURDAY BUT POST FRONTAL PRECIPITATION LOOKS TO LINGER OVER THE HIGHWAY 84 CORRIDOR THROUGH MID MORNING. THE REMAINDER OF THE AREA WILL START THE LONG TERM PERIOD DRY. A 1030MB HIGH CENTERED OVER THE OZARKS WILL SHIFT EAST TO THE TENNESSEE VALLEY BY SATURDAY EVENING HELPING TO BRING A COOLER AND MUCH DRIER AIRMASS TO OUR CWA. PWS WILL BE KNOCKED DOWN FROM GREATER THAN AN INCH AND A HALF AHEAD OF THE COLD FRONT FRIDAY TO AROUND A QUARTER OF AN INCH BY NOON SATURDAY. THE CAA IN THE WAKE OF THE FRONT WILL HOLD AFTERNOON HIGHS IN THE 60S SATURDAY AND MORNING LOWS IN THE 40S SUNDAY. THE SURFACE HIGH WILL SHIFT EAST TO THE MID ATLANTIC SEABOARD BY SUNDAY MORNING RESULTING IN WEAK RETURN FLOW AHEAD OF AN APPROACHING SHORTWAVE. THIS SOUTHERN STREAM SHORTWAVE IS EXPECTED TO BE MOVING ACROSS THE SOUTHERN PLAINS SUNDAY MORNING. IT SHOULD TAKE MOST OF SUNDAY MORNING TO MOISTEN OUR AIRMASS TO ALLOW FOR RAIN TO FALL OVER THE WESTERN ZONES BY NOON AND THEN SPREAD EAST ACROSS THE REMAINDER OF OUR CWA SUNDAY AFTERNOON. THE RAIN WILL CONTINUE SUNDAY NIGHT AS THE SHORTWAVE SHIFTS EAST ACROSS THE REGION. BY MONDAY MORNING LOWER 60 DEGREE DEW POINTS AND INCH AND A HALF PWS WILL BE BACK OVER OUR CWA. MONDAY THROUGH TUESDAY CONVECTION WILL BE MOSTLY DIURNALLY DRIVEN. TUESDAY NIGHT THOUGH A NEARLY STATIONARY FRONTAL BOUNDARY WILL DRIFT INTO THE NORTHERN PORTIONS OF OUR CWA AND SERVE TO FOCUS CONVECTION. AS BROAD TROUGHING ALOFT REMAINS OVER THE WESTERN CONUS THE RESULTING SOUTHWEST FLOW ALOFT LOOKS TO BRING SEVERAL SHORTWAVES THAT WILL COMBINE WITH THE BOUNDARY...ABUNDANT MOISTURE AND DAYTIME HEATING FOR PERIODS OF HEAVY RAIN WEDNESDAY AND THURSDAY. MODEL RUN ACCUMULATIONS OF THE GFS AND ECMWF SHOW SEVERAL INCHES OF RAIN DURING THIS PERIOD AND MAINLY NORTH OF INTERSTATE 20. /22/ && .AVIATION...CIGS WILL CONTINUE TO GRADUALLY IMPROVE TO VFR ACROSS THE AREA THIS MORNING...EXCEPT IN AREAS OF SHRA/TSRA WHICH ARE EXPECTED TO BE MAINLY NORTH OF THE I-20 CORRIDOR. OVERNIGHT... CONDITIONS ARE EXPECTED TO DETERIORATE BACK INTO MVRF/IFR RANGE AREAWIDE DUE TO LOW STRATUS AND PATCHY FOG...IMPROVING AGAIN BY MID MORNING FRIDAY. SW WINDS WILL BE GUSTY AT TIMES THROUGH THIS AFTERNOON...WITH GUSTS IN THE 25-35 KT RANGE POSSIBLE. /DL/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 83 65 83 48 / 24 10 35 72 MERIDIAN 81 61 82 46 / 20 14 23 64 VICKSBURG 83 66 81 47 / 23 11 43 71 HATTIESBURG 83 63 83 56 / 18 8 20 44 NATCHEZ 84 67 83 48 / 19 10 33 62 GREENVILLE 80 65 77 44 / 27 18 64 48 GREENWOOD 81 66 79 44 / 33 20 58 60 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1038 AM CDT THU APR 2 2015 .UPDATE... ISSUED AT 1039 AM CDT THU APR 2 2015 FORECAST CHALLENGE FOR TODAY WILL BE WINDS AND SOME LIGHT PRECIP ACROSS THE NORTH. WIND SHIFT ASSOCIATED WITH FRONTAL BOUNDARY DROPPING IN FROM CANADA IS JUST NORTH OF THE BORDER...BETWEEN WINNIPEG AND THE INTL BORDER. WINDS ACROSS NORTH DAKOTA GENERALLY FROM THE WEST AND INTO ADVISORY CRITERIA ACROSS CNTRL ND. STRONGER WINDS SHOULD GET INTO WESTERN ZONES BY NOONTIME...AND ONLY IMPACT NORTHWEST ZONES FOR A SHORT PERIOD BEFORE SHIFTING TO THE NW. WESTERLY WINDS WILL CONTINUE ALONG AND SOUTH OF HWY 200 FOR MUCH OF THE AFTN...WITH THE BEST MIXING AND STRONGEST WINDS ACROSS THE FAR SOUTHERN ZONES MID AFTN. HAVE ISSUED A WIND ADVISORY FROM NOONTIME TO 7 PM CDT. ALSO MADE SIGNIFICANT CHANGES TO POPS AS CURRENT ECHOES WEST OF THE CWA AND MOST OF CWA IS CLEAR...WITH CLOUDS NOW INCREASING OVER NORTHEAST ND. USED RUC AS GUIDANCE AND DELAYED ONSET OF PRECIP. UPDATE ISSUED AT 657 AM CDT THU APR 2 2015 MAIN CHALLENGE REMAINS WINDS AND TEMPS. STILL EXPECT WINDS TO INCREASE WITH INVERSION BREAK AROUND 15Z AND ARE REFLECTED IN THE FCST. ALSO EXPECTING WINDS TO HOVER NEAR ADVISORY CRITERIA IN THE SW ZONES...BUT WILL HOLD OFF ON ANY HEADLINES FOR NOW. TEMPS SO FAR LOOKING OKAY SO WILL NOT MAKE ANY ADJUSTMENTS ATTM. REST OF FORECAST ON TARGET. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 358 AM CDT THU APR 2 2015 MAIN CHALLENGE WILL BE WINDS AND TEMPS FOR TODAY. UPPER TROF WILL PUSH ACROSS THE AREA TODAY...AND ASSOCIATED SFC SYSTEM WILL BRING COOLER AIR ALONG WITH A CHANCE FOR SHOWERS. WINDS WILL INCREASE IN TIGHTENING GRADIENT...AND MODEL SOUNDINGS INDICATE AN ADIABATIC LAYER. UNIDIRECTIONAL WINDS ARE ALSO SHOWN THRU AROUND 850MB TO ALLOW MIXING OF 35-40 KTS DOWN TO THE SFC. STRONGEST WINDS WILL BE IN THE FAR SRN ZONES...BUT MARGINALLY CLOSE TO ADVISORY CRITERIA FOR ONLY A FEW HOURS SO WILL HOLD ON ANY WIND HEADLINES FOR NOW. COOL AND DRY WEATHER IS IN STORE FOR FRIDAY AS CANADIAN SFC HIGH PRESSURE MOVES OVER THE FA. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 358 AM CDT THU APR 2 2015 FOR FRIDAY NIGHT INTO SATURDAY NIGHT...UPPER PATTERN SHOWS MORE OF A NW FLOW REGIME WITH ANOTHER WAVE FCST TO CROSS THE AREA...BRINGING ANOTHER CHANCE FOR LIGHT PCPN. OTHERWISE...EXPECT MAINLY COOL CONDITIONS TO PERSIST. SUNDAY THROUGH WEDNESDAY...FLOW PATTERN BEGINS TO SHIFT WITH SOME MORE SIGNIFICANT TROUGHS DIGGING INTO THE WESTERN CONUS AND THEN COMING OUT INTO THE PLAINS. ONE SUCH SYSTEM WILL BRING WEST TO SOUTHWESTERLY FLOW ALOFT ACROSS THE NORTHERN PLAINS FOR SUNDAY...AND THE ECMWF BREAKS OUT SOME PRECIP WITH A LEAD SHORTWAVE. THINK THAT MUCH OF THE ACTIVITY WILL HOLD OFF UNTIL MONDAY WHEN THE SYSTEM PROGRESSES INTO THE NORTHERN ROCKIES. THE GEM TRACKS A STRONG SFC LOW JUST TO OUR SOUTH AND DUMPS OVER A FOOT OF SNOW ALL THE WAY NORTH OF FARGO...BUT THE OTHER DETERMINISTIC MODELS ARE WEAKER AND FURTHER SOUTH WITH THEIR MAIN DEFORMATION BAND. WILL CONTINUE TO KEEP POPS HIGH WITH A MIX OF RAIN AND SNOW FOR NOW AND WILL KEEP A CLOSE EYE ON THE SYSTEM AS IT DRAWS CLOSER. COLD SFC HIGH PRESSURE WILL BUILD DOWN INTO THE AREA FOR TUESDAY AND WEDNESDAY...AND THINK WE SHOULD DRY OUT BY THAT POINT BUT TEMPS WILL REMAIN BELOW SEASONAL AVERAGES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 657 AM CDT THU APR 2 2015 MAINLY VFR CONDITIONS TODAY WITH GUSTY WINDS ASSOCIATED WITH STRONG LOW PRESSURE. CURRENT OBSERVATIONS IN THE NW CORNER OF ND SHOW SOME MVFR CIGS...AND EXPECT THEM TO CROSS THE NRN PART OF THE FA. OTHERWISE...WINDS IN GRADIENT LEVEL MOSTLY UNIDIRECTIONAL SO NOT EXPECTING SIGNIFICANT ISSUES WITH LOW LEVEL TURBULENCE. && .FIRE WEATHER... ISSUED AT 358 AM CDT THU APR 02 2015 TEMPS WILL BE MUCH COOLER THAN YESTERDAY...BUT WITH DEW POINTS IN THE 20S AFTERNOON RELATIVE HUMIDITY VALUES WILL GET DOWN INTO THE 20 TO 35 PERCENT RANGE IN OUR SOUTHERN COUNTIES. PORTIONS OF WEST CENTRAL MINNESOTA ARE EXPECTED TO BE THE DRIEST AND DROP BELOW 25 PERCENT...BUT THE STRONGEST WINDS WILL BE IN SOUTHEASTERN NORTH DAKOTA. WITH THE WINDS OVER 30 MPH AND WITH VERY DRY FUELS...FIRES COULD SEE EXPLOSIVE GROWTH EVEN WITH RH VALUES IN THE BORDERLINE CATEGORY. THUS...WILL INCLUDE A RED FLAG WARNING FOR ALL OF THE SOUTHERN COUNTIES. IF THE COLD FRONT COMES IN A BIT FASTER THAN EXPECTED THERE COULD BE SOME RH RECOVERY...BUT FOR NOW IT SEEMS THAT THE AFTERNOON WILL BE VERY DRY AND WINDY SO WILL GO WITH THE RED FLAG AND LATER SHIFTS CAN CANCEL EARLY IF NEEDED. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR NDZ038-039-049- 052-053. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ006-014-015-024- 026-028>030-038-039-049-052-053. MN...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR MNZ003-024- 027>032-040. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ002-003-022- 027>032-040. && $$ UPDATE...SPEICHER SHORT TERM...HOPKINS LONG TERM...HOPKINS/JR AVIATION...HOPKINS FIRE WEATHER...JR
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1010 AM EDT THU APR 2 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO TODAY AND DRAG A WARM FRONT ACROSS OHIO AND THE LOWER GREAT LAKES REGION. A COLD FRONT WILL FOLLOW MOVING THROUGH FROM THE NORTHWEST DURING THE EVENING. THE COLD FRONT WILL STALL ACROSS SOUTHERN OHIO FRIDAY AS LOW PRESSURE MOVES NORTHEAST ALONG THE BOUNDARY. HIGH PRESSURE WILL TRY TO BUILD OVER THE REGION FROM THE SOUTH THIS WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MADE SOME CHANGES TO ACCOUNT FOR THE LINE OF SHOWERS MOVING ACROSS THE AREA. SOME EMBEDDED THUNDER BEING REPORTED AS WELL. BEHIND THIS LINE THERE WILL BE A SEVERAL HOUR PERIOD OF MAINLY DRY WEATHER AND HAVE TRIED TO ACCOUNT FOR THAT AS WELL. THIS CONVECTION APPEARS TO BE ELEVATED AND ASSOCIATED WITH A WARM FRONT ALOFT AS SURFACE DEWPOINTS REMAIN VERY LOW. NOT SURE HOW FAR EAST IT WILL GET BEFORE THE DRY AIR WINS OUT. HAVE RAMPED UP WINDS SOME FOR THIS AFTERNOON...ESPECIALLY IN NW OHIO. LOCAL SCHEMES SUGGEST GUSTS COULD GET CLOSE TO ADVISORY CRITERIA. WILL GO WITH 40 MPH FOR NOW AND CONTINUE TO MONITOR. CLOUDS INCREASING FROM THE WEST AND NORTHWEST OVERNIGHT AHEAD OF APPROACHING SYSTEM HOWEVER CLOUDS AT THIS POINT REMAIN FAIRLY THIN AND ANY PRECIP WELL WEST OF THE AREA. BY 12Z THE HRRR HAS SHOWERS INTO THE WESTERN COUNTIES. SREF ALSO HAD PRECIP NEAR THE AREA AT 12Z WHILE THE NAM PRINTS OUT A SWATH OF CAPE ON OUR WESTERN BORDER. GIVEN THIS WILL BEGIN WITH CHANCE POPS IN THE WEST AT 12Z. BY 15Z DECENT MOISTURE REACHES AS FAR EAST AS CLEVELAND. FURTHER SATURATION OCCURS EAST IN THE AFTERNOON. WILL HAVE POPS INCREASE TO LIKELY IN THE WEST THROUGH THE MID/LATE MORNING WITH CATEGORICAL POPS WEST EARLY AFTERNOON...SWEEPING EAST-SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING. ALSO...WILL HAVE THUNDER BEGIN AT NOON. MAIN CONCERN WILL BE POTENTIAL FOR SEVERE WITH DEEP MOISTURE AND AFTERNOON HEATING COMBINE WITH INCREASING LOW LEVEL SHEAR. AT THIS TIME WESTERN COUNTIES IN A MARGINAL OUTLOOK WITH BEST CHANCES SOUTHWEST OF THE AREA. HIGHS WELL INTO THE 60S WITH 70 NOT OUT OF THE QUESTION. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... TONIGHT BEGINS WITH WHAT WILL LIKELY BE A LINE OF CONVECTION IN OR MOVING INTO WESTERN OHIO WHICH WILL MOVE SLOWLY EAST-SOUTHEAST THROUGH THE NIGHT. WILL HAVE CAT POPS AND WILL CONTINUE WITH THUNDER THROUGH THE EVENING BUT DROP IT FOR THE OVERNIGHT AS INSTABILITY DECREASES. BY FRIDAY MORNING THE FRONT SHOULD BE IN SOUTHERN OHIO WITH A BRIEF PERIOD OF WEAK HIGH PRESSURE AND DRIER AIR BUILDING IN FROM THE NORTH. BY FRIDAY EVENING HOWEVER...MODELS SHOW LOW PRESSURE MOVES ALONG THE FRONT IN SOUTHERN OHIO SPREADING MOISTURE AND INSTABILITY BACK INTO THE AREA FROM THE SOUTH. WILL BEGIN WITH ONLY A SLIGHT CHANCE POPS SOUTH BUT INCREASE TO CHANCE THROUGH THE MORNING. BY AFTERNOON BROUGHT CATEGORICAL POPS BACK TO A LARGE PORTION OF THE AREA. RAIN CONTINUES INTO THE NIGHT AND THE TRICKY BIT IS THAT COLD ADVECTION BEHIND THE LOW WILL LIKELY TURN PRECIP OVER TO SNOW AFTER MIDNIGHT. THIS WILL BE A CLASSIC ISSUE OF HOW LONG WILL SNOW OCCUR BEFORE THE PRECIP ENDS. MODELS HAVE SHOW SOME CONSISTENCY PAST COUPLE NIGHT WITH SNOW AFTER MIDNIGHT WITH A COUPLE INCHES POSSIBLE BY MORNING. THE MOST SHOULD BE IN THE ELEVATED AREAS OF NWRN PA WHERE 4 INCHES COULD FALL. DONT EXPECT WARNING AMOUNTS BUT COULD POSSIBLY END UP NEEDING AN ADVISORY. PRECIP SHOULD END BY 12Z SATURDAY MOST PLACES AND WILL CONTINUE INTO SAT MORNING ONLY FOR NWRN PA AND XTRM NERN OHIO. SAT MID MORNING AND AFTERNOON SHOULD BE DRY AS HIGH PRESSURE BUILDS IN. NEXT CHANCE OF PRECIP COMES LATE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT BACK DOORS INTO THE AREA. NOT A LOT OF FORCING SO WILL HAVE ONLY CHANCE/SLIGHT CHANCE POPS. SUNDAY NIGHT HOWEVER THE GFS IS SHOWING THAT THE GLFMX MOISTURE GETS TAPPED...REACHING INTO THE AFTER AFTER MIDNIGHT SO WILL HAVE CHANCE POPS FOR ALL. CHILLY SATURDAY BEHIND THE FRONT BUT OTHERWISE NEAR TO ABOVE NORMAL TEMPS. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... A WARMER AND WET PATTERN SETTING UP FOR THE EXTENDED. MODELS CONTINUE WITH A NEARLY STATIONARY FRONT ACROSS THE AREA ON MONDAY. THEN LOW PRESSURE SYSTEM MOVES ALONG STATIONARY FRONT TUESDAY. ECMWF TRACK AND TIMING FASTER THAN LATEST GFS. FRONT SAGS SOUTH OF AREA AS A COLD FRONT WEDNESDAY...BUT THEN A SECOND LOW MOVES NE ALONG THE BOUNDARY THURSDAY. AGAIN PRECISE TIMING STILL IN DOUBT SO WILL CONTINUE WITH HIGH CHANCE POPS AFTER TUESDAY. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... WARM FRONT ALONG IL/IN BORDER WILL MOVE NE ACROSS THE FORECAST AREA LATE THIS MORNING. WILL SEE SOME SCATTERED SHOWERS WITH THE FRONT BUT HAVE DOUBTS AS TO HOW WIDESPREAD IT WILL BE. COLD FRONT NOW INTO CENTRAL IOWA...WILL MOVE ACROSS THE AREA TONIGHT. BEHIND THE FRONT UPWARDS OF A HALF INCH OF RAIN POSSIBLE TOMORROW NIGHT WITH IFR CONDITIONS. SOUTH WINDS WILL INCREASE TO 20 TO 30 KNOTS LATE THIS MORNING. BUT UNTIL WINDS MIX DOWN COULD SEE SOME LLWS AS 2K FT WINDS ARE FROM THE SSW AT 40-45 KT. .OUTLOOK...NON-VFR INTO SATURDAY. NON VFR POSSIBLE SUNDAY MAINLY EXTREME NE OH/NW PA. && .MARINE... WINDS WILL PICK UP FROM THE SOUTH TO SOUTHWEST ACROSS THE LAKE TODAY AS WARM FRONT LIFTS NE ACROSS THE LAKE. WINDS TURN TO THE NORTHWEST TONIGHT AND DIMINISH FAIRLY QUICKLY AS COLD FRONT PUSHES ACROSS THE LAKE. NORTHWEST FLOW INCREASES FRIDAY NIGHT AS LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY. WINDS AGAIN DIMINISH SATURDAY NIGHT INTO SUNDAY AS HIGH PRESSURE MOVES ACROSS THE LAKE. LIGHT AND VARIABLE FLOW IS EXPECTED UNDER THE INFLUENCE OF THE HIGH AND THEN STATIONARY FRONT THROUGH MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK/KUBINA SHORT TERM...TK LONG TERM...DJB AVIATION...DJB MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
632 AM EDT THU APR 2 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO TODAY AND DRAG A WARM FRONT ACROSS OHIO AND THE LOWER GREAT LAKES REGION. A COLD FRONT WILL FOLLOW MOVING THROUGH FROM THE NORTHWEST DURING THE EVENING. THE COLD FRONT WILL STALL ACROSS SOUTHERN OHIO FRIDAY AS LOW PRESSURE MOVES NORTHEAST ALONG THE BOUNDARY. HIGH PRESSURE WILL TRY TO BUILD OVER THE REGION FROM THE SOUTH THIS WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED HOURLY TEMPS WHICH WERE TOO LOW. ALSO ADJUSTED CLOUD COVER. NO OTHER CHANGES. SHOWERS BEGINNING TO DEVELOP IN INDIANA SO LEFT IN THE MORNING POPS WEST. CLOUDS INCREASING FROM THE WEST AND NORTHWEST OVERNIGHT AHEAD OF APPROACHING SYSTEM HOWEVER CLOUDS AT THIS POINT REMAIN FAIRLY THIN AND ANY PRECIP WELL WEST OF THE AREA. BY 12Z THE HRRR HAS SHOWERS INTO THE WESTERN COUNTIES. SREF ALSO HAD PRECIP NEAR THE AREA AT 12Z WHILE THE NAM PRINTS OUT A SWATH OF CAPE ON OUR WESTERN BORDER. GIVEN THIS WILL BEGIN WITH CHANCE POPS IN THE WEST AT 12Z. BY 15Z DECENT MOISTURE REACHES AS FAR EAST AS CLEVELAND. FURTHER SATURATION OCCURS EAST IN THE AFTERNOON. WILL HAVE POPS INCREASE TO LIKELY IN THE WEST THROUGH THE MID/LATE MORNING WITH CATEGORICAL POPS WEST EARLY AFTERNOON...SWEEPING EAST-SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING. ALSO...WILL HAVE THUNDER BEGIN AT NOON. MAIN CONCERN WILL BE POTENTIAL FOR SEVERE WITH DEEP MOISTURE AND AFTERNOON HEATING COMBINE WITH INCREASING LOW LEVEL SHEAR. AT THIS TIME WESTERN COUNTIES IN A MARGINAL OUTLOOK WITH BEST CHANCES SOUTHWEST OF THE AREA. HIGHS WELL INTO THE 60S WITH 70 NOT OUT OF THE QUESTION. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... TONIGHT BEGINS WITH WHAT WILL LIKELY BE A LINE OF CONVECTION IN OR MOVING INTO WESTERN OHIO WHICH WILL MOVE SLOWLY EAST-SOUTHEAST THROUGH THE NIGHT. WILL HAVE CAT POPS AND WILL CONTINUE WITH THUNDER THROUGH THE EVENING BUT DROP IT FOR THE OVERNIGHT AS INSTABILITY DECREASES. BY FRIDAY MORNING THE FRONT SHOULD BE IN SOUTHERN OHIO WITH A BRIEF PERIOD OF WEAK HIGH PRESSURE AND DRIER AIR BUILDING IN FROM THE NORTH. BY FRIDAY EVENING HOWEVER...MODELS SHOW LOW PRESSURE MOVES ALONG THE FRONT IN SOUTHERN OHIO SPREADING MOISTURE AND INSTABILITY BACK INTO THE AREA FROM THE SOUTH. WILL BEGIN WITH ONLY A SLIGHT CHANCE POPS SOUTH BUT INCREASE TO CHANCE THROUGH THE MORNING. BY AFTERNOON BROUGHT CATEGORICAL POPS BACK TO A LARGE PORTION OF THE AREA. RAIN CONTINUES INTO THE NIGHT AND THE TRICKY BIT IS THAT COLD ADVECTION BEHIND THE LOW WILL LIKELY TURN PRECIP OVER TO SNOW AFTER MIDNIGHT. THIS WILL BE A CLASSIC ISSUE OF HOW LONG WILL SNOW OCCUR BEFORE THE PRECIP ENDS. MODELS HAVE SHOW SOME CONSISTENCY PAST COUPLE NIGHT WITH SNOW AFTER MIDNIGHT WITH A COUPLE INCHES POSSIBLE BY MORNING. THE MOST SHOULD BE IN THE ELEVATED AREAS OF NWRN PA WHERE 4 INCHES COULD FALL. DONT EXPECT WARNING AMOUNTS BUT COULD POSSIBLY END UP NEEDING AN ADVISORY. PRECIP SHOULD END BY 12Z SATURDAY MOST PLACES AND WILL CONTINUE INTO SAT MORNING ONLY FOR NWRN PA AND XTRM NERN OHIO. SAT MID MORNING AND AFTERNOON SHOULD BE DRY AS HIGH PRESSURE BUILDS IN. NEXT CHANCE OF PRECIP COMES LATE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT BACK DOORS INTO THE AREA. NOT A LOT OF FORCING SO WILL HAVE ONLY CHANCE/SLIGHT CHANCE POPS. SUNDAY NIGHT HOWEVER THE GFS IS SHOWING THAT THE GLFMX MOISTURE GETS TAPPED...REACHING INTO THE AFTER AFTER MIDNIGHT SO WILL HAVE CHANCE POPS FOR ALL. CHILLY SATURDAY BEHIND THE FRONT BUT OTHERWISE NEAR TO ABOVE NORMAL TEMPS. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... A WARMER AND WET PATTERN SETTING UP FOR THE EXTENDED. MODELS CONTINUE WITH A NEARLY STATIONARY FRONT ACROSS THE AREA ON MONDAY. THEN LOW PRESSURE SYSTEM MOVES ALONG STATIONARY FRONT TUESDAY. ECMWF TRACK AND TIMING FASTER THAN LATEST GFS. FRONT SAGS SOUTH OF AREA AS A COLD FRONT WEDNESDAY...BUT THEN A SECOND LOW MOVES NE ALONG THE BOUNDARY THURSDAY. AGAIN PRECISE TIMING STILL IN DOUBT SO WILL CONTINUE WITH HIGH CHANCE POPS AFTER TUESDAY. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... WARM FRONT ALONG IL/IN BORDER WILL MOVE NE ACROSS THE FORECAST AREA LATE THIS MORNING. WILL SEE SOME SCATTERED SHOWERS WITH THE FRONT BUT HAVE DOUBTS AS TO HOW WIDESPREAD IT WILL BE. COLD FRONT NOW INTO CENTRAL IOWA...WILL MOVE ACROSS THE AREA TONIGHT. BEHIND THE FRONT UPWARDS OF A HALF INCH OF RAIN POSSIBLE TOMORROW NIGHT WITH IFR CONDITIONS. SOUTH WINDS WILL INCREASE TO 20 TO 30 KNOTS LATE THIS MORNING. BUT UNTIL WINDS MIX DOWN COULD SEE SOME LLWS AS 2K FT WINDS ARE FROM THE SSW AT 40-45 KT. .OUTLOOK...NON-VFR INTO SATURDAY. NON VFR POSSIBLE SUNDAY MAINLY EXTREME NE OH/NW PA. && .MARINE... WINDS WILL PICK UP FROM THE SOUTH TO SOUTHWEST ACROSS THE LAKE TODAY AS WARM FRONT LIFTS NE ACROSS THE LAKE. WINDS TURN TO THE NORTHWEST TONIGHT AND DIMINISH FAIRLY QUICKLY AS COLD FRONT PUSHES ACROSS THE LAKE. NORTHWEST FLOW INCREASES FRIDAY NIGHT AS LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY. WINDS AGAIN DIMINISH SATURDAY NIGHT INTO SUNDAY AS HIGH PRESSURE MOVES ACROSS THE LAKE. LIGHT AND VARIABLE FLOW IS EXPECTED UNDER THE INFLUENCE OF THE HIGH AND THEN STATIONARY FRONT THROUGH MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...DJB AVIATION...DJB MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
621 AM EDT THU APR 2 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO TODAY AND DRAG A WARM FRONT ACROSS OHIO AND THE LOWER GREAT LAKES REGION. A COLD FRONT WILL FOLLOW MOVING THROUGH FROM THE NORTHWEST DURING THE EVENING. THE COLD FRONT WILL STALL ACROSS SOUTHERN OHIO FRIDAY AS LOW PRESSURE MOVES NORTHEAST ALONG THE BOUNDARY. HIGH PRESSURE WILL TRY TO BUILD OVER THE REGION FROM THE SOUTH THIS WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED HOURLY TEMPS WHICH WERE TOO LOW. ALSO ADJUSTED CLOUD COVER. NO OTHER CHANGES. SHOWERS BEGINNING TO DEVELOP IN INDIANA SO LEFT IN THE MORNING POPS WEST. CLOUDS INCREASING FROM THE WEST AND NORTHWEST OVERNIGHT AHEAD OF APPROACHING SYSTEM HOWEVER CLOUDS AT THIS POINT REMAIN FAIRLY THIN AND ANY PRECIP WELL WEST OF THE AREA. BY 12Z THE HRRR HAS SHOWERS INTO THE WESTERN COUNTIES. SREF ALSO HAD PRECIP NEAR THE AREA AT 12Z WHILE THE NAM PRINTS OUT A SWATH OF CAPE ON OUR WESTERN BORDER. GIVEN THIS WILL BEGIN WITH CHANCE POPS IN THE WEST AT 12Z. BY 15Z DECENT MOISTURE REACHES AS FAR EAST AS CLEVELAND. FURTHER SATURATION OCCURS EAST IN THE AFTERNOON. WILL HAVE POPS INCREASE TO LIKELY IN THE WEST THROUGH THE MID/LATE MORNING WITH CATEGORICAL POPS WEST EARLY AFTERNOON...SWEEPING EAST-SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING. ALSO...WILL HAVE THUNDER BEGIN AT NOON. MAIN CONCERN WILL BE POTENTIAL FOR SEVERE WITH DEEP MOISTURE AND AFTERNOON HEATING COMBINE WITH INCREASING LOW LEVEL SHEAR. AT THIS TIME WESTERN COUNTIES IN A MARGINAL OUTLOOK WITH BEST CHANCES SOUTHWEST OF THE AREA. HIGHS WELL INTO THE 60S WITH 70 NOT OUT OF THE QUESTION. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... TONIGHT BEGINS WITH WHAT WILL LIKELY BE A LINE OF CONVECTION IN OR MOVING INTO WESTERN OHIO WHICH WILL MOVE SLOWLY EAST-SOUTHEAST THROUGH THE NIGHT. WILL HAVE CAT POPS AND WILL CONTINUE WITH THUNDER THROUGH THE EVENING BUT DROP IT FOR THE OVERNIGHT AS INSTABILITY DECREASES. BY FRIDAY MORNING THE FRONT SHOULD BE IN SOUTHERN OHIO WITH A BRIEF PERIOD OF WEAK HIGH PRESSURE AND DRIER AIR BUILDING IN FROM THE NORTH. BY FRIDAY EVENING HOWEVER...MODELS SHOW LOW PRESSURE MOVES ALONG THE FRONT IN SOUTHERN OHIO SPREADING MOISTURE AND INSTABILITY BACK INTO THE AREA FROM THE SOUTH. WILL BEGIN WITH ONLY A SLIGHT CHANCE POPS SOUTH BUT INCREASE TO CHANCE THROUGH THE MORNING. BY AFTERNOON BROUGHT CATEGORICAL POPS BACK TO A LARGE PORTION OF THE AREA. RAIN CONTINUES INTO THE NIGHT AND THE TRICKY BIT IS THAT COLD ADVECTION BEHIND THE LOW WILL LIKELY TURN PRECIP OVER TO SNOW AFTER MIDNIGHT. THIS WILL BE A CLASSIC ISSUE OF HOW LONG WILL SNOW OCCUR BEFORE THE PRECIP ENDS. MODELS HAVE SHOW SOME CONSISTENCY PAST COUPLE NIGHT WITH SNOW AFTER MIDNIGHT WITH A COUPLE INCHES POSSIBLE BY MORNING. THE MOST SHOULD BE IN THE ELEVATED AREAS OF NWRN PA WHERE 4 INCHES COULD FALL. DONT EXPECT WARNING AMOUNTS BUT COULD POSSIBLY END UP NEEDING AN ADVISORY. PRECIP SHOULD END BY 12Z SATURDAY MOST PLACES AND WILL CONTINUE INTO SAT MORNING ONLY FOR NWRN PA AND XTRM NERN OHIO. SAT MID MORNING AND AFTERNOON SHOULD BE DRY AS HIGH PRESSURE BUILDS IN. NEXT CHANCE OF PRECIP COMES LATE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT BACK DOORS INTO THE AREA. NOT A LOT OF FORCING SO WILL HAVE ONLY CHANCE/SLIGHT CHANCE POPS. SUNDAY NIGHT HOWEVER THE GFS IS SHOWING THAT THE GLFMX MOISTURE GETS TAPPED...REACHING INTO THE AFTER AFTER MIDNIGHT SO WILL HAVE CHANCE POPS FOR ALL. CHILLY SATURDAY BEHIND THE FRONT BUT OTHERWISE NEAR TO ABOVE NORMAL TEMPS. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... A WARMER AND WET PATTERN SETTING UP FOR THE EXTENDED. MODELS CONTINUE WITH A NEARLY STATIONARY FRONT ACROSS THE AREA ON MONDAY. THEN LOW PRESSURE SYSTEM MOVES ALONG STATIONARY FRONT TUESDAY. ECMWF TRACK AND TIMING FASTER THAN LATEST GFS. FRONT SAGS SOUTH OF AREA AS A COLD FRONT WEDNESDAY...BUT THEN A SECOND LOW MOVES NE ALONG THE BOUNDARY THURSDAY. AGAIN PRECISE TIMING STILL IN DOUBT SO WILL CONTINUE WITH HIGH CHANCE POPS AFTER TUESDAY. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... WARM FRONT JUST SW OF STL WILL MOVE NE ACROSS THE FORECAST AREA LATE THIS MORNING. WILL SEE SOME SCATTERED SHOWERS WITH THE FRONT BUT HAVE DOUBTS AS TO HOW WIDESPREAD IT WILL BE. COLD FRONT NOW ACROSS WISCONSIN...WILL MOVE ACROSS THE AREA TONIGHT. AHEAD OF THE FRONT SOUTH WINDS WILL INCREASE TO 20 TO 30 KNOTS THIS AFTERNOON. BEHIND THE FRONT UPWARDS OF A HALF INCH OF RAIN POSSIBLE TOMORROW NIGHT WITH IFR CONDITIONS. .OUTLOOK...NON-VFR INTO SATURDAY. NON VFR POSSIBLE SUNDAY MAINLY EXTREME NE OH/NW PA. && .MARINE... WINDS WILL PICK UP FROM THE SOUTH TO SOUTHWEST ACROSS THE LAKE TODAY AS WARM FRONT LIFTS NE ACROSS THE LAKE. WINDS TURN TO THE NORTHWEST TONIGHT AND DIMINISH FAIRLY QUICKLY AS COLD FRONT PUSHES ACROSS THE LAKE. NORTHWEST FLOW INCREASES FRIDAY NIGHT AS LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY. WINDS AGAIN DIMINISH SATURDAY NIGHT INTO SUNDAY AS HIGH PRESSURE MOVES ACROSS THE LAKE. LIGHT AND VARIABLE FLOW IS EXPECTED UNDER THE INFLUENCE OF THE HIGH AND THEN STATIONARY FRONT THROUGH MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...DJB AVIATION...DJB MARINE...DJB
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1045 AM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE WILL MOVE EAST OF THE AREA TODAY ALLOWING FOR THE RETURN OF MOIST SOUTHERLY FLOW. A COLD FRONT WILL PUSH THROUGH NORTHEAST GEORGIA AND THE WESTERN CAROLINAS ON FRIDAY EVENING AHEAD OF DRIER HIGH PRESSURE FOR THE WEEKEND. MOISTURE WILL RETURN FOR THE START OF THE NEXT WORK WEEK AS SOUTHERLY FLOW INCREASES PRECIPITATION CHANCES THROUGH MIDWEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM EDT...CLOUDINESS HAS EXPANDED ACROSS THE AREA AS ANTICIPATED BUT TEMPERATURES CONTINUE TO RUN A TAD BELOW FORECAST TRENDS AS A RESULT...SO HAVE MADE MINOR ADJUSTMENTS TO HOURLY TRENDS AS WELL AS AFTERNOON HIGH TEMPS. BASED ON HIRES MODEL GUIDANCE... HAVE BACKED OFF POPS ESPECIALLY THROUGH LATE THIS MORNING BUT AFTERNOON TREND WITH POPS AND CONVECTION LOOK FAIRLY SIMILAR TO GOING FORECAST. RAP CONTINUES TO WANT TO BRING IN UPWARDS OF 1000 J/KG SBCAPE INTO WEST AND SOUTHWEST PORTIONS OF THE FORECAST AREA AND WITH WEAK SHEAR PREVIOUS THINKING FOR EVENING CONVECTION REMAINS. OVERALL ONLY MINOR CHANGES TO THE NEAR-TERM FORECAST. FOR TODAY...MOISTURE RETURN FROM THE GULF AND ATLANTIC WILL CONTINUE AS THE UPPER RIDGE AXIS MOVES EAST AND OFFSHORE THIS MORNING...AND A DAMPENING SHORT WAVE APPROACHES FROM THE WEST. THE COMBINATION OF A DEVELOPING LOW LEVEL SE UPSLOPE FLOW AND LOW LEVEL ISENTROPIC UPGLIDE IS EXPECTED TO FORCE LOW CLOUDS AND LIGHT PRECIP THAT WILL EXPAND FROM THE BLUE RIDGE THROUGH MIDDAY AND INTO THE AFTERNOON. HAVE LIMITED THE PRECIP PROBABILITY TO THE CHANCE RANGE INTO THE AFTERNOON. TEMPS WILL BE 5-10 DEGREES COOLER THAN YESTERDAY BECAUSE OF THE EXPANDING LOW CLOUDS AND PRECIP CHANCES. THE WILDCARD IN THE FCST IS THE PASSAGE OF THE SHORTWAVE THIS AFTERNOON. THE FORCING ASSOCIATED WITH THE WAVE SHOULD INTERSECT AN UNSTABLE BOUNDARY LAYER ACRS N/NE GEORGIA AND HELP TO TRIGGER SOME DEEPER CONVECTION...WHICH THE MODELS CARRY EASTWARD ACROSS UPSTATE SC AND THE SRN PIEDMONT OF NC INTO THIS EVENING. FOR NOW...WILL LIMIT THE FCST TO THE LOWER END OF THE CHC RANGE OUT OF UNCERTAINTY WITH HOW MUCH DESTABILIZATION WILL ACTUALLY OCCUR. FOR TONIGHT...THE PASSAGE OF THE WAVE WILL BRING THE LOW LEVEL FLOW AROUND TO SOMETHING MORE S OR SW...AND WILL ALSO PUSH THE BEST ISENTROPIC UPGLIDE AWAY TO THE NE. THAT SHOULD SLOWLY ELIMINATE OUR PRECIP POTENTIAL INTO THE EARLY MORNING HOURS. THE MODELS SUGGEST THERE WILL BE A LULL BY AROUND DAYBREAK FRIDAY AS WE AWAIT THE ARRIVAL OF THE MAIN COLD FRONT. MIN TEMPS SHOULD BE MILD. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 AM EDT THURSDAY...THE SHORT TERM FCST PERIOD INITIALIZES FRIDAY MORNING AMIDST A DEPARTING SHORTWAVE TROF LEAVING QUASI ZONAL FLOW BEHIND OVER THE SOUTHEAST. FURTHER WEST...A SERIES OF WAVES ALOFT...ONE NORTHERN STREAM...AND ONE IN THE SOUTHERN STREAM ARE FCST TO PHASE AS THEY ENTER THE ARKLATEX REGION BY MIDDAY FRIDAY. SURFACE CYCLOGENESIS WILL BE UNDERWAY...AND WILL LIKELY INTENSIFY AS THE ABOVE MENTIONED PHASING HAPPENS ALOFT. A COLD FRONT STRETCHING FROM THE NORTHERN OH VALLEY SOUTHWARD TO THE GULF COAST WILL ADVECT EAST THROUGH THE DAY INTERACTING WITH A MOIST/UNSTABLE WARM SECTOR OVER THE MIDSOUTH WHERE LATEST NAM/GFS GUIDANCE FAVORS UPWARDS OF 1200-1500J/KG SBCAPE ALONG WITH A 40-50KT LLJ PROVIDING AMPLE SHEAR. FURTHER EAST OVER THE SOUTHERN APPS...DESPITE CONTINUED SOUTHERLY FLOW...DEWPOINTS ARE NOT ALL THAT IMPRESSIVE AS A POCKET OF RELATIVELY DRIER GULF AIR ADVECTS IN EARLY ON FRIDAY. THEREFORE...EXPECTING A LINE OF STRONG/SEVERE CONVECTION TO PUSH EAST THROUGH THE TN VALLEY LATE DAY FRIDAY BEFORE SLIDING INTO THE WESTERN NC MOUNTAINS AROUND MIDNIGHT. THIS LINE SHOULD WEAKEN AS IT ENTERS THE HIGH TERRAIN AS THE AIRMASS WILL NOT BE AS FAVORABLE FOR SUSTAINMENT. THAT SAID...AS THE LLJ ADVECTS INTO THE REGION AHEAD OF THE PRIMARY SURFACE TROF...MODELS CONTINUE TO FCST NEARLY 30KTS 0-3KM BULK SHEAR WITH SRH VALUES IN EXCESS OF 250 M2/S2 THROUGH THE SAME LAYER WHICH COULD SUPPORT STRONG CONVECTION OVER THE NC HIGH COUNTRY AND NORTHEAST GA. ACROSS THE LOWER TERRAIN EXPECTING AN EVEN MORE STABLE...LESS SHEARED ENVIRONMENT TO BE IN PLACE WHICH WOULD FAVOR MORE GENERAL SHOWERS/THUNDERSTORMS OVERNIGHT WITH THE FROPA. BY SATURDAY MORNING THE FRONT WILL BE EXITING THE REGION TO THE EAST WITH HIGH PRESSURE SPILLING IN. MODELS CONTINUE TO FAVOR A BAND OF LLV MOISTURE BANKED UP AGAINST THE WESTERN SLOPES OF THE NC MOUNTAINS BEHIND THE FRONT AROUND MIDDAY. THUS ALTHOUGH CONFIDENCE IS LOW...FALLING THICKNESSES COULD YIELD A BRIEF RAIN/SNOW SHOWER OR TWO ACROSS THE HIGHER PEAKS AND RIDGETOPS OF THE NORTHERN NC MOUNTAINS WHICH WILL NOT YIELD ANY ACCUMULATION. OTHERWISE...SKIES WILL CLEAR OUT THROUGH THE DAY ON SATURDAY AS BRIEF NORTHWEST WINDS AID DOWNSLOPING FLOW WITH HIGHS TOPPING OUT A FEW DEGREES BELOW NORMAL. AS THE SURFACE HIGH SLIDES OVERHEAD SATURDAY NIGHT...EXPECTING GOOD RADIATIONAL COOLING CONDITIONS AIDED BY LIGHT/CALM SURFACE FLOW. MODELS HAVE TRENDED SLIGHTLY COOLER FOR SUNDAY MORNING...THUS WILL MENTION FREEZE CONDITIONS POSSIBLE OVER THE SOUTHWEST NC MOUNTAINS WHILE ALSO ADDING WORDING FOR FROST OUTSIDE OF THE MOUNTAINS AS LOWS FALL TO NEARLY 15-20 DEGREES BELOW NORMAL. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 330 AM EDT THURSDAY...THE MEDIUM RANGE FCST PERIOD INITIALIZES SUNDAY MORNING AMIDST PATCHY/WIDESPREAD FROST AND OR FREEZE CONDITIONS AS SURFACE HIGH PRESSURE PREVAILS OVERHEAD. MODELS FAVOR SAID HIGH PRESSURE SLIDING EAST THROUGH THE DAY WITH A DRY...YET COOL EASTER HOLIDAY IN STORE. AS THE RIDGE SETS UP OFFSHORE...SOUTHERLY FLOW WILL RETURN ACROSS THE SOUTHEAST INTO THE NEW WORK WEEK YIELDING INCREASED MOISTURE AND PRECIPITATION CHANCES ON MONDAY AS A WEAK SHORTWAVE SLIDES THROUGH THE TN VALLEY REGION. PRECIPITATION CHANCES WILL REMAIN ELEVATED THROUGH THE PERIOD AS MODELS CONTINUE TO PREVAIL BROAD WAA REGIME OVER THE SOUTHEAST LEADING TO UNSETTLED WEATHER HIGHLIGHTED BY POTENTIAL DIURNAL SHOWERS AND THUNDERSTORMS...ALONG WITH WEAK UPSLOPE INDUCED PRECIPITATION OVER THE HIGH TERRAIN. THAT SAID...CONFIDENCE REMAINS MODEST AT BEST REGARDING DIURNAL CHANCES AS MODELS INDICATE BROAD UPPER RIDGING WILL ESTABLISH ITSELF BY MIDWEEK EFFECTIVELY HELPING TO TAMP DOWN CONVECTION. LATE IN THE PERIOD BOTH THE GFS/ECMWF FAVOR POSSIBLE CAD EXTENSION FROM PARENT HIGH PRESSURE ATOP THE NORTHEAST AHEAD OF A DEVELOPING SYSTEM OVER THE ARKLATEX...ALL WARRANTING CONTINUED POPS DUE TO UNCERTAINTY OF ANY POSSIBLE UPGLIDE REGIME ESTABLISHMENT ALONG WITH ABOVE MENTIONED DIURNAL PRECIPITATION CHANCES. TEMPERATURES THROUGH THE PERIOD WILL GRADUALLY MODERATE AMONGST WAA REGIME LEADING TO ABOVE NORMAL TEMPERATURES BY MIDWEEK. && .AVIATION /15Z THURSDAY THROUGH MONDAY/... AT KCLT /15Z UPDATE/...LOW VFR CONTINUES FOR THE TIME BEING BUT EXPECT MVFR CIGS TO DEVELOP A LITTLE EARLIER THAN PREVIOUSLY ADVERTISED...WITH VCSH OR PERHAPS -DZ DEVELOPING NEAR OR AFTER 18Z. PREVIOUS DISCUSSION FOLLOWS...VFR...FOR THE TIME BEING. MODEL GUIDANCE HAS DEPICTED THE DEVELOPMENT OF LOW CLOUDS FAIRLY WELL EARLY THIS MORNING IN THE STRENGTHENING MOIST SE UPSLOPE FLOW. MOST OF THE LOW CLOUD CEILINGS WILL BE CLOSER TO THE BETTER MECHANICAL LIFT NEAR THE BLUE RIDGE THRU MID MORNING. OVER THE WRN PIEDMONT...THE CLOUD BASE IS EXPECTED TO BE CLOSER TO 050-060. THE BETTER PLUME OF LOW MOISTURE MOVES EAST LATER IN THE DAY AND MAY ALLOW AN MVFR CEILING TO FORM BY THE MID AFTERNOON. THE MODELS DIFFER ON THE AMOUNT OF PRECIP DEVELOPMENT EAST OVER THE PIEDMONT LATE IN THE DAY. HAVE KEPT PRECIP OUT OF THE TAF FOR NOW UNTIL MORE GUIDANCE FROM THE CONVECTION-ALLOWING MODELS IS SEEN. AFTER SUNSET...THE LAMP GUIDANCE GROWS MORE PESSIMISTIC WITH AN IFR CEILING SPREADING EAST FROM THE BLUE RIDGE. HAVE KEPT THAT OUT FOR NOW...AS IT MAY DEPEND ON PRECIP DEVELOPMENT. ELSEWHERE...MVFR CIGS WILL GRADUALLY EXPAND FROM THE BLUE RIDGE AND SHOULD IMPACT KAVL AND THE UPSTATE SC TAFS AS THE MOIST UPGLIDE DEEPENS THRU MID MORNING. AT THAT POINT...SOME OF THE GUIDANCE... PARTICULARLY THE LAMP...DEVELOPS AN IFR CEILING IN THE UPSLOPE FLOW AREAS NEAR THE BLUE RIDGE AND THEN FANS IT OUT ACROSS THE UPSTATE/NC FOOTHILLS. NOT CONFIDENT ENOUGH TO INCLUDE AN IFR CEILING IN THE NEW TAFS DURING PEAK HEATING WITHOUT A FAVORABLE LOCATION OF SURFACE HIGH PRESSURE FOR COLD AIR DAMMING AND WITHOUT A HIGH PRECIP PROBABILITY. FEEL THAT MVFR IS A BIT MORE LIKELY GIVEN THE WARM APRIL SUN...BUT WILL CONSIDER KEEPING A TEMPO FOR IFR IN LATER AMENDMENTS. CONDITIONS MAY DETERIORATE AS WE LOSE HEATING... PARTICULARLY OVER THE NC FOOTHILLS. STILL A CHANCE FOR A THUNDERSTORM AT KAND AS THE UPPER SHORT WAVE MOVES THRU AND A PROB30 WAS KEPT THERE...BUT PUSHED BACK TO THE EARLY EVENING PER THE SPC 4KM WRF. EXPECT LOW CLOUDS TO PREVAIL THRU THE EVENING HOURS...BUT HAVE HELD OFF WITH THE IFR CEILINGS FOR NOW. OUTLOOK...MOIST SOUTHEAST UPSLOPE FLOW WILL MOVE OFF FRIDAY MORNING WHICH SHOULD ALLOW LOW CLOUD CEILINGS TO SCATTER AND LIFT. CONDITIONS WILL IMPROVE TO VFR BY FRIDAY AFTERNOON. A COLD FRONT WILL AFFECT THE AREA FRIDAY NIGHT INTO EARLY SATURDAY...BRINGING ANOTHER ROUND OF RAIN/POSSIBLE THUNDERSTORMS AND RESTRICTIONS. VFR WILL RETURN FOR THE REST OF THE WEEKEND. CONFIDENCE TABLE... 14-20Z 20-02Z 02-08Z 08-12Z KCLT HIGH 100% HIGH 97% HIGH 82% HIGH 100% KGSP HIGH 86% MED 69% MED 65% HIGH 100% KAVL MED 78% MED 73% HIGH 87% MED 75% KHKY HIGH 87% MED 76% MED 68% HIGH 100% KGMU HIGH 91% MED 65% LOW 56% HIGH 100% KAND HIGH 82% MED 79% MED 78% HIGH 81% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...CDG/RWH NEAR TERM...PM/TDP SHORT TERM...CDG LONG TERM...CDG AVIATION...PM/TDP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1051 AM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE WILL MOVE OFF THE MID-ATLANTIC COAST TODAY. A SERIES OF DISTURBANCES ALOFT AND AN ASSOCIATED COLD FRONT WILL SLOWLY MOVE TOWARD THE REGION THROUGH FRIDAY...MOVING ACROSS THE REGION FRIDAY NIGHT AND SATURDAY. RAIN SHOWERS AND A FEW THUNDERSTORMS WILL SPREAD INTO THE WEST TODAY...THEN ACROSS THE REGION FRIDAY AND EARLY SATURDAY. COOLER...DRIER CONDITIONS ARE EXPECTED DURING THE WEEKEND. UNSETTLED WEATHER WILL RETURN EARLY NEXT WEEK AND CONTINUE MUCH OF THE WEEK AS THE STORM TRACK STALLS OVER THE REGION. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM EDT THURSDAY... THE VERY DRY HIGH PRESSURE AREA ALONG THE VA COAST WILL MOVE FURTHER EAST OUT TO SEA TODAY. MEANWHILE...A CHAOTIC BARRAGE OF NORTHERN AND SOUTHERN STREAM SYSTEMS EMBEDDED WITHIN AN EXPANSIVE AREA OF WSW UPPER FLOW EMANATING FROM A BROAD UPPER TROUGH IN THE SOUTHWEST U.S. WILL BRING WAVES OF PRECIPITATION TO THE REGION THROUGH FRIDAY AND ALSO HELP TO PUSH A COLD FRONT TOWARD THE REGION IN PHASES THROUGH FRIDAY AS WELL AS. THE FIRST IN THIS SERIES OF SHORT WAVES...NOW ASSOCIATED WITH A DISSIPATING AREA OF SHRA/TSRA ACROSS CENTRAL KY...WILL TRACK NORTHEAST POTENTIALLY CLIPPING OUR NORTHWESTERN CWA THIS EVENING. PER THE MORNING RNK UPPER AIR SOUNDING...OUR REGION IS STILL CONFINED WITHIN DRY ANTECEDENT AIR MASS IN THE WAKE OF THE AFOREMENTIONED SFC HIGH. ANY MOISTENING WILL LIKELY TAKE PLACE FROM TOP DOWN. THUS...FEEL ALL OF THE MODELS...AND ESPECIALLY THE GFS...ARE WAY OVERDONE ON MEASURABLE QPF TODAY...WITH THE EXCEPTION OF AREAS WEST OF THE APPALACHIAN DIVIDE WHERE OPPORTUNITY FOR SOME LOW LEVEL MOISTENING WILL OCCUR UP THROUGH THE TENNESSEE VALLEY. THE HRRR SEEMS TO HAVE THE BEST HANDLE ON CURRENT ACTIVITY AND PLACEMENT FOR THIS EVENING WHICH SUGGESTS THE ACTIVITY IN KENTUCKY...ALTHOUGH IN A WEAKENED STATE...WILL STILL MANAGE TO CROSS INTO WVA AND POTENTIALLY REACH THE BLUEFIELD AND LEWISBURG AREAS BY SUNDOWN. WILL MONITOR RADAR TRENDS AND RAISE POPS AFTER I TAKE A LOOK AT THE NEW 12Z GUIDANCE. ANOTHER UPPER LEVEL DISTURBANCE IS FOLLOWING QUICK ON THE HEELS OF THE FIRST AND IS PROGGED TO LIFT NORTHEAST THROUGH THE OHIO VALLEY INTO WVA TONIGHT. AGAIN...EXPECT THE VAST MAJORITY OF THE ASSOCIATED PRECIPITATION TO REMAIN NORTH OF THE AREA. HOWEVER...EACH SHORT WAVE WILL ACT TO NUDGE THE FRONT A LITTLE FARTHER SOUTH. GIVEN THAT THE INITIAL UPPER SUPPORT IS BETTER TO THE NORTH...THE FRONT WILL SHOW MORE EASTWARD MOVEMENT NORTH OF THE MASON-DIXON LINE THAN IN OUR REGION THROUGH FRI...THUS ALLOWING THE FRONT WITH TIME TO TAKE ON MORE OF A WEST-EAST CONFIGURATION AS OPPOSED TO A NORTH-SOUTH CONFIGURATION. FINALLY BY FRIDAY...A STRONGER NORTHERN STREAM SHORT WAVE WILL GIVE THE FRONTAL BOUNDARY A GOOD PUSH THROUGH THE REGION. UNTIL THAT TIME...HAVE DOWNPLAYED POPS CONSIDERABLY FROM MODEL/MOS POPS THIS AFTERNOON/OVERNIGHT...AND ACTUALLY DO NOT HAVE ANY HIGH CHANCE/LIKELY POPS...AND EVEN THAT ONLY IN THE EXTREME WEST- NORTHWEST...UNTIL ALMOST THE END OF THE PERIOD...12Z FRI. WINDS WILL VEER TO THE SSW THROUGH THE MORNING AND BECOME GUSTY AS THE PRESSURE GRADIENT TIGHTENS BETWEEN THE DEPARTING SFC HIGH AND THE APPROACHING FRONTAL SYSTEM. THE SOUTH WINDS WILL HELP TO BOOST TEMPERATURES INTO THE 60S AND 70S ACROSS THE REGION TODAY...BUT CONSIDERABLE CLOUD COVER WILL REDUCE INSOLATION AND OFFSET THE LOW-LEVEL WAA. EXPECT HIGHS TO RANGE FROM THE 50S IN THE MOUNTAINS TO AROUND 70 ACROSS THE PIEDMONT. REDUCED DEWPOINTS A FEW DEGREES EAST OF THE BLUE RIDGE FROM MODEL BLEND IN CONSIDERATION OF THE ANTECEDENT VERY DRY AIR MASS. && .SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/... AS OF 230 AM EDT THURSDAY... THE FRIDAY THROUGH FRIDAY NIGHT TIME PORTION OF THE FORECAST WILL BE AN ACTIVE ONE. BY FRIDAY MORNING...A COLD FRONT IN ASSOCIATION WITH LOW PRESSURE ENTERING QUEBEC WILL BE ON OUR WESTERN DOORSTEP. DURING THE COURSE OF THE DAY...THE FRONT WILL STALL ACROSS THIS LOCATION...OR PERHAPS EVEN LIFT A LITTLE NORTH...AS ITS PARENT LOW CONTINUES ITS EASTWARD TRACK. CONCURRENTLY...ANOTHER LOW WILL MOVE ALONG THE FRONT OUT OF EAST TEXAS START TO PUT A BUCKLE IN THE FRONT AS IT HEADS TOWARD THE LOWER OHIO VALLEY. THIS SCENARIO IS STILL IN TUNE WITH OUR PREVIOUS FORECAST OF THE GREATEST CONCENTRATION OF SHOWERS CURVING FROM THE WESTERN PART OF OUR REGION FRIDAY INTO THE NORTHERN SECTORS. THIS PORTION OF THE FORECAST AREA SHOULD EXPECT TO EXPERIENCE A GENEROUS COVERAGE OF PRECIPITATION THROUGHOUT THE DAY. PORTIONS OF SOUTHSIDE VIRGINIA AND NEIGHBORING SECTIONS OF NORTH CENTRAL NORTH CAROLINA MAY ONLY EXPERIENCE ISOLATED SHOWERS AT BEST...WITH GREATEST POTENTIAL OF THESE DURING THE MID TO LATE AFTERNOON. 00Z/8PM GFS AND NAM GUIDANCE ARE STILL OFFERING THE POTENTIAL FOR SOME THUNDERSTORMS ON FRIDAY WITH FORECAST SURFACE BASED CAPE REACHING 800-1000 J/KG AND SURFACE BASED LIFTED INDICES IN THE -3 TO -4 RANGE. HAVE CONTINUED IN LINE WITH OUR EARLIER FORECAST WITH THE BEST THUNDER POTENTIAL NEAREST THE SURFACE FRONT DURING THE AFTERNOON HOURS. SOUTHWEST 850 MB WINDS AHEAD OF THE FRONT ARE PROGGED TO REACH 40 TO 50 KTS. WHILE STRAIGHT-LINE WIND GUSTS OF WIND ADVISORY LEVEL ARE NOT ANTICIPATED THANKS TO THE NEARLY PARALLEL TO THE RIDGES ORIENTATION AND ROUGHLY 5000 FT MSL MIXING HEIGHT...THE INVERTED-V NATURE OF THE FORECAST SOUNDINGS OFFER THE POTENTIAL FOR STRONG GUSTS ASSOCIATED WITH ANY OF THE STORMS OR STRONGER SHOWERS THAT DEVELOP...ESPECIALLY BY THE LATE AFTERNOON. MILD CONDITIONS ARE ANTICIPATED WITHIN AN AREA OF STRONG WARM AIR ADVECTION DESPITE PLENTY OF CLOUD COVER...AND PRECIPITATION IN THE WEST. ANTICIPATE HIGHS TO RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS...WITH MID TO UPPER 70S ACROSS THE PIEDMONT. FRIDAY NIGHT...THE LOWER OHIO VALLEY LOW PRESSURE SYSTEM IS PROGGED TO ADVANCE INTO PENNSYLVANIA...AND THEN EVENTUALLY TO NEW ENGLAND BY DAYBREAK SATURDAY. THIS SCENARIO WILL ALLOW THE STALLED FRONTAL BOUNDARY TO RACE ACROSS THE AREA FRIDAY NIGHT AS A STRONG COLD FRONT BRINGING THE FOCUS FOR THE GREATEST CONCENTRATION OF SHOWERS ACROSS THE AREA. NOTABLY COLDER AIR WILL SURGE INTO THE AREA...WITH 850 MB TEMPERATURE DROPPING TO AROUND -4 C ACROSS THE NORTHWEST BY SATURDAY MORNING. SCATTERED SHOWERS...AND ISOLATED STORMS...WILL ACCOMPANY THE FRONT AS IT PASSES THROUGH THE AREA FRIDAY EVENING. COVERAGE MAY INITIALLY BE LESS JUST AS THE FRONT CROSSES THE BLUE RIDGE...BUT THEN REORGANIZE TO BETTER COVERAGE OVER THE SOUTHEASTERN PARTS OF THE AREA AS IT ENCOUNTERS BETTER CONVERGENCE ALONG A LEE TROUGH. ACROSS WESTERN PARTS OF THE AREA...PRECIPITATION WILL TEND TO DECREASE IN COVERAGE BEHIND THE FRONT. HOWEVER...THOSE PREFERRED UPSLOPE AREAS OF SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA WILL MAINTAIN SOME ISOLATED TO SCATTERED SHOWERS THROUGH THE DAYTIME SATURDAY. TEMPERATURES MAY BE COLD ENOUGH FOR RAIN TO MIX WITH OR CHANGE TO SNOW AROUND OR ABOVE 4000 FT MSL LATE FRIDAY NIGHT INTO EARLY SATURDAY MORNING. LITTLE IF ANY ACCUMULATION IS EXPECTED. LOW TEMPERATURES FRIDAY NIGHT WILL RANGE FROM THE MID 30S TO THE LOWER 40S ACROSS THE MOUNTAINS TO THE MID 40S TO NEAR 50 ACROSS THE PIEDMONT. NORTHWEST FLOW 850 MB WINDS INCREASE IN THE WAKE OF THE COLD FRONT...BUT EVEN MORE SO BY 12Z/8AM SATURDAY AFTER THE PASSAGE OF THE UPPER LEVEL SHORTWAVE TROUGH IN THE 40 TO 50 KT RANGE. AT THIS TIME...OUR SURFACE WIND SPEED/GUSTS ACROSS MOST OF OUR REGION WILL BE FORECAST BELOW WIND ADVISORY THRESHOLDS. THERE MAY BE A THREE TO FIVE HOUR WINDOW CENTERED AROUND 8AM THAT ELEVATIONS OVER 4000 FT MSL ACROSS THE NORTHERN MOUNTAINS OF NORTH CAROLINA AND THE ADJOINING GRAYSON HIGHLANDS OF WV VA MAY SEE SOME GUSTS ABOVE ADVISORY THRESHOLDS. SPEEDS/GUSTS ACROSS THE ENTIRE REGION WILL DECREASE THROUGH THE DAY AS 850 MB WINDS ARE PROGGED TO SLOW TO 20KTS AS HIGH PRESSURE BUILDS INTO THE REGION. ANY LINGERING UPSLOPE RAIN/SNOW SHOWERS IN THE WEST WILL END BY MIDDAY. HIGH TEMPERATURES WILL RANGE FROM THE UPPER 40S TO LOWER 50S ACROSS THE MOUNTAINS TO THE MID 50S TO LOWER 60S ACROSS THE PIEDMONT. SATURDAY NIGHT INTO SUNDAY...THE CENTER OF SURFACE HIGH PRESSURE WILL MOVE OVERHEAD FROM THE WEST...AND HEAD OFF THE COAST OF THE CAROLINAS BY SUNDAY AFTERNOON. ANTICIPATE LITTLE IF ANY CLOUD COVER SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL BE NOTABLY COOLER SATURDAY NIGHT AS THE HIGH IS DIRECTLY OVERHEAD. ANTICIPATE LOWS AROUND 30 TO THE LOWER 30S ACROSS THE MOUNTAINS WITH LOW TO MID 30S ACROSS THE PIEDMONT. ON SUNDAY...LIGHT AND VARIABLE WIND WILL TREND SOUTH AT 5 TO 10 MPH BY THE AFTERNOON AS THE AREA BECOMES POSITIONED ON THE WEST SIDE OF THE HIGH PRESSURE. HIGH TEMPERATURES WILL REACH THE UPPER 50S TO LOWER 60S ACROSS THE MOUNTAINS WITH LOW TO MID 60S ACROSS THE PIEDMONT. SUNDAY NIGHT...THE SOUTHERLY FLOW WILL TREND A LITTLE MORE SOUTHWEST IN ADVANCE OF THE NEXT SYSTEM HEADING THROUGH THE CENTER PORTION OF THE COUNTRY. THE AREA SHOULD AT LEAST SEE AN INCREASE IN MID TO HIGH LEVEL CLOUD COVER. THE 00Z/8PM GFS AND ECMWF HINT AT SOME PRECIPITATION ARRIVING IN THE WEST BY DAYBREAK MONDAY. AT THIS TIME...WILL NOT JUMP ON THIS POTENTIAL QUITE YET IN THE FORECAST. LOW WILL BE MILDER AS COMPARED TO SATURDAY NIGHT THANKS TO THE SOUTHWEST FLOW AND INCREASED CLOUD COVER. EXPECT LOWS IN THE UPPER 30S TO LOWER 40S ACROSS THE MOUNTAINS AND LOW TO MID 40S ACROSS THE PIEDMONT. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 430 AM EDT WEDNESDAY... THE FIRST PART OF NEXT WEEK WILL SEE A SERIES OF WEAK UPPER LEVEL SHORT WAVES MOVE THROUGH AS THE AIRMASS OVER THE EASTERN US BECOMES WARMER AND MORE MOIST THANKS TO PERSISTENT SOUTHWESTERLY WINDS. THIS SHOULD SET US UP FOR BOUTS OF DIURNAL CONVECTION WITH A CHANCE OF SHOWERS AND THUNDERSTORMS JUST ABOUT EACH AFTERNOON...BECOMING MORE LIKELY ACROSS WESTERN PORTIONS OF THE AREA. AS WE GO OUT IN TIME MODEL GUIDANCE STARTS TO DIFFER ON TIMING OF WEATHER SYSTEMS BUT IT APPEARS THE NEXT COLD FRONT APPROACHING FROM THE WEST WILL NOT AFFECT OUR REGION UNTIL LATE WEDNESDAY AT THE EARLIEST. && .AVIATION /15Z THURSDAY THROUGH MONDAY/... AS OF 745 AM EDT THURSDAY... A VERY DRY AIR MASS RESIDES OVER THE AREA EARLY THIS MORNING IN THE WAKE OF A LARGE AREA OF HIGH PRESSURE MOVING OFF THE VA COAST AT THIS HOUR. UPSTREAM ARE A SERIES OF SHORT WAVES EMBEDDED WITHIN AN INCREASINGLY ZONAL AND ACTIVE UPPER FLOW. THE FIRST OF THESE SHORT WAVES WILL SPREAD RAPIDLY TOWARD THE REGION THROUGH THE DAY. MODELS...ESPECIALLY THE GFS...ARE WAY TO AGGRESSIVE GIVEN THE VERY DRY AIR MASS IN PLACE...DEWPOINTS STILL IN THE SINGLE DIGITS AND TEENS ACROSS MUCH OF THE AREA...IN GENERATING MEASURABLE QPF WITH THIS FIRST FEATURE. FEEL LARGELY THAT THIS FIRST FEATURE WILL SIMPLY SERVE TO MOISTEN THE ATMOSPHERE FOR MORE APPRECIABLE MOISTURE WITH THE SECOND SHORT WAVE TO ARRIVE THU NIGHT/FRI MORNING. MODEL TIME-HEIGHT CROSS-SECTIONS AND BUFKIT MODEL SOUNDINGS SHOW THAT THE BULK OF THE MOISTURE THROUGH 00Z REMAINS REMAINS AOA100 DROPPING INTO THE 045-080 RANGE AFT 06Z. THUS...FOR NOW...HAVE IGNORED THE WIDESPREAD 0.10-0.20 INCH 6-HR QPF GENERATED BY THE GFS AND THE MODEL GENERATED TAFS OF CIGS AOB 025 BY 00Z. HAVE NOT INTRODUCED ANY SUB-VFR CIGS AT THIS POINT...THINKING THAT THIS WILL WAIT UNTIL AT LEAST DAYBREAK FRI IN THE WEST...AND FRI LATE AFTERNOON/EVENING EAST OF THE BLUE RIDGE. WILL INCLUDE A PROB30 FOR -RA/SPRINKLES BLF- LWB DURING THE LATE AFTERNOON WHERE THE MOISTURE SHOULD BECOME A LITTLE DEEPER MORE QUICKLY AND ANY UPSTREAM -SHRA FROM THE FIRST SHORT WAVE MAY SPREAD INTO EASTERN WV/FAR SW VA AS SPRINKLES BEFORE DISSIPATING. A BETTER CHANCE OF -RA REACHING EASTERN WV SHOULD OCCUR AFT 08Z WITH THE NEXT UPSTREAM SHORT WAVE. VISIBILITIES WILL NOT BE AN ISSUE THROUGH THE TAF VALID PERIOD. WINDS...LIGHT SE MOST LOCATIONS AT THE ONSET...VEERING TO SSW THROUGH THE DAY AND INCREASING TO 10-12KTS WITH GUSTS 20-22KTS POSSIBLE AS THE PRESSURE GRADIENT INCREASES BETWEEN THE DEPARTING SFC HIGH AND LOW PRESSURE DRAPED FROM THE SOUTHERN PLAINS TO THE NORTHEAST. MEDIUM TO HIGH CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD. HIGH CONFIDENCE IN VFR VSBYS THROUGH THE TAF VALID PERIOD. MEDIUM CONFIDENCE IN WIND DIR THROUGH THE TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND SPD THROUGH THE TAF VALID PERIOD. EXTENDED AVIATION FORECAST... A SLOW MOVING...INCREASINGLY WEST-EAST ORIENTED COLD FRONT WILL APPROACH THE REGION FROM THE NORTHWEST FRI...MOVING THROUGH THE REGION FRI NIGHT/SAT MORNING AS AN UPSTREAM NORTHERN STREAM SHORT WAVE FINALLY KICKS THE FRONT SOUTHEAST. MUCH OF THE DAY FRIDAY...EXPECT THE PRECIPITATION TO REMAIN MOSTLY NORTHWEST OF THE CWA...MOVING INTO EASTERN WV DURING THE AFTERNOON...SPREADING ACROSS THE REMAINDER OF THE CWA AS A NARROW LINE OF CONVECTION FRI EVENING/EARLY SATURDAY. A FEW THUNDERSTORMS ARE POSSIBLE...MAINLY WESTERN AREAS. SEVERE WEATHER IS NOT EXPECTED. COLDER TEMPERATURES AND UPSLOPE -SHRA...POSSIBLY -SHSN AT THE HIGHER ELEVATIONS...ARE POSSIBLE EARLY SATURDAY BEFORE CLEARING TAKES PLACE. GUSTY NORTHWEST WINDS ARE EXPECTED SATURDAY BEHIND THE FRONT. HIGH PRESSURE WILL BUILD INTO THE REGION SAT AFTERNOON-SUN WITH VFR CONDITIONS EXPECTED. AN EXTENDED PERIOD OF SUB-VFR CONDITIONS APPEARS LIKELY MUCH OF NEXT WEEK AS THE AREA REMAINS TRAPPED UNDER AN ACTIVE STORM TRACK FROM A BROAD AREA OF LOW PRESSURE IN THE SOUTHWEST U.S. MULTIPLE ROUNDS OF SHOWERS AND A FEW THUNDERSTORMS APPEAR LIKELY THROUGH THE PERIOD. && .FIRE WEATHER... AS OF 445 AM EDT THURSDAY... ANTECEDENT VERY DRY HIGH PRESSURE ALONG THE VA COAST THIS MORNING WILL MOVE FURTHER OUT TO SEA TODAY. A SERIES OF UPPER-LEVEL DISTURBANCES AND AN ASSOCIATED FRONTAL BOUNDARY WILL APPROACH FROM THE WEST...BUT TAKE UNTIL FRI NIGHT TO MOVE THROUGH THE REGION. LIGHT RAIN SHOWERS WILL MOVE INTO THE WESTERN MOUNTAINS BY EVENING AND OVERNIGHT...BUT WILL NOT REACH AREAS EAST OF THE BLUE RIDGE UNTIL FRIDAY...POSSIBLY NOT EVEN UNTIL FRIDAY AFTERNOON. RH VALUES WILL SLOWLY INCREASE TODAY FROM THE WEST...BUT AREAS EAST OF THE BLUE RIDGE WILL ONLY SEE MODEST RECOVERY AND WITH MIXING COULD EASILY SEE MIN RH VALUES DROP TO 20 PERCENT BY AFTERNOON. IN ADDITION...A TIGHTENING PRESSURE GRADIENT BETWEEN THE DEPARTING HIGH AND THE APPROACHING FRONT/LOW PRESSURE TROUGH WILL RESULT IN STRENGTHENING SSW WINDS ACROSS THE REGION BY LATE MORNING/EARLY AFTERNOON. SUSTAINED WIND SPEEDS ARE EXPECTED TO REMAIN BELOW CRITERIA...BUT THE FUELS HAVE CONTINUED TO DRY AND WIDESPREAD 10-HR FUEL MOISTURES OF 6-7 PERCENT NOTED ACROSS MUCH OF THE CWA. FURTHERMORE...SPC PLANS AN ELEVATED FIRE WEATHER AREA ACROSS OUR EASTERN COUNTIES. THUS...WILL ISSUE AN SPS FOR INCREASED FIRE DANGER ALONG TO EAST OF THE BLUE RIDGE...WHICH LINES UP WITH LWX/AKQ/RAH PLANS AS WELL. THE GOOD NEWS IS THAT THIS SHOULD BE THE LAST DAY OF THIS CONCERN...AT LEAST UNTIL THE WEEKEND...AND POSSIBLY BEYOND DEPENDING ON RAINFALL FRI-SAT WITH THE ASSOCIATED FRONTAL BOUNDARY. NEXT WEEK LOOKS VERY WET AND UNSETTLED...SO THIS COULD BE THE END OF ELEVATED FIRE WEATHER THREAT FOR SOMETIME TO COME. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...RAB NEAR TERM...PM/RAB SHORT TERM...DS LONG TERM...MBS AVIATION...RAB/RCS FIRE WEATHER...RAB
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
933 AM CDT THU APR 2 2015 .UPDATE... WELL... THE CHANCE FOR RAIN HAS SIGNIFICANTLY DIMINISHED THIS MORNING. THE CHANCE FOR THUNDER IS NOW GONE. SCATTERED SHOWERS WILL TRACK ACROSS SOUTH CENTRAL AND SOUTHEAST WI DURING THE MORNING HOURS ALONG THE SURFACE TROUGH. THIS TROUGH IS EXPECTED TO CLEAR SOUTHEAST WI BY 1 PM TODAY. PRECIPITATION AMOUNTS WILL BE LESS THAN PREVIOUSLY EXPECTED GIVEN THE WEAKENING NATURE OF THE PRECIP ALONG THIS TROUGH. VISIBLE SATELLITE IS SHOWING CLEARING BEHIND THIS TROUGH IN MINNESOTA. THIS CLEARING WILL WORK ITS WAY ACROSS WI THIS AFTERNOON AND EXPECT A PERIOD OF SUNSHINE. TEMPERATURES WILL REBOUND INTO THE MID 60S TODAY. && .AVIATION/18Z TAFS/... SHOWERS WITH OCCASIONAL MVFR CIGS WILL TRACK ACROSS SOUTH CENTRAL AND SOUTHEAST WI THROUGH THE MORNING AHEAD OF A SURFACE LOW PRESSURE TROUGH. EXPECT PRECIP CHANCES TO END FROM WEST TO EAST THROUGH 18Z. LOOK FOR VFR CONDITIONS THROUGH THE REMAINDER OF THE FORECAST. && .MARINE... WINDS AND WAVES HAVE DIMINISHED BELOW SMALL CRAFT ADVISORY LEVELS THIS MORNING AS THE SURFACE TROUGH MOVES ACROSS THE AREA. THUS... CANCELLED THE SMALL CRAFT ADVISORY. && .FIRE WEATHER... FIRE WEATHER CONDITIONS ARE NOT QUITE AS CRITICAL AS YESTERDAY SINCE MOST AREAS RECEIVED AT LEAST A LITTLE RAIN. COOLER TEMPERATURES AND LOWER WINDS ALSO LOWERING THE THREAT. HOWEVER... LOW DEW POINTS WILL BRING RELATIVE HUMIDITY VALUES DOWN TO AROUND 25 PERCENT NORTHWEST OF MADISON TO FOND DU LAC THIS AFTERNOON. && .PREV DISCUSSION... /ISSUED 332 AM CDT THU APR 2 2015/ TODAY...FORECAST CONFIDENCE MEDIUM. AWAITING SHOWERS OVER NE IOWA IN REGION OF MOISTURE CONVERGENCE ALONG SURFACE TROUGH AND STRONGER 700 MB OMEGA AHEAD OF MID-LEVEL TROUGH AXIS THAT WILL ACCOMPANY LEAD VORT MAX ACROSS REGION THIS MORNING. LEADING LINE OF SHOWERS AND THUNDERSTORMS THAT MOVED INTO WEST CENTRAL WISCONSIN LAST EVENING ERODED AS THEY MOVED AWAY FROM THIS BETTER FORCING AND WERE OUTRUN BY OUTFLOW BOUNDARY. WIND GUSTS SHOULD ALSO DIMINISH WITH APPROACH OF SURFACE TROUGH AND AS 60-70KT LOW-LEVEL JET HEELS OVER TO THE EAST. HAVE KEPT MENTION OF ISOLATED THUNDERSTORMS THOUGH ELEVATED CAPE ALMOST NON-EXISTENT ON LATEST RAP FORECAST SOUNDINGS. HOWEVER... SPC MESOANALYSIS SHOWS AREA OF 500 J/KG MOST-UNSTABLE CAPE THAT COULD BRUSH SOUTHERN WISCONSIN SO CAN/T RULE OUT A RUMBLE OR TWO OF THUNDER. HAVE PRECIPITATION CHANCES IN THE FAR SOUTHEAST AFTER 18Z UNTIL 850 MB TROUGH CLEARS TO THE EAST. 925 MB TEMPS REBOUND BETWEEN 18Z AND 00Z AND ENOUGH AFTERNOON SUN TO BRING HIGH TEMPS IN THE 60S. TONIGHT...FORECAST CONFIDENCE ACTUAL COLD FRONT FINALLY DROPS THROUGH SOUTHERN WISCONSIN AFTER MIDNIGHT TONIGHT AFTER PASSAGE OF WEAK SECONDARY WAVE. CLOUDS AND MIXING WITH WEST TO NORTHWEST WINDS OF 5 TO 10 MPH WILL KEEP LOWS INT EH MID TO UPPER 30S. FRIDAY AND SATURDAY...FORECAST CONFIDENCE...MEDIUM COULD SEE A LITTLE LIGHT RAIN CLIP THE SOUTH FRIDAY MORNING...AS A SHORTWAVE APPROACHES. RAIN CHANCES THEN FOCUS IN THE EAST DURING THE AFTERNOON DUE TO DECENT LOW LEVEL CONVERGENCE. MAY EVEN SEE A MIX WITH SNOW LATER IN THE AFTERNOON TOWARD THE LAKE AS COLDER AIR MOVES IN. SHOULD BE DRY SATURDAY...WITH SOUTHERN WISCONSIN SITTING BETWEEN HIGH PRESSURE TO THE SOUTH AND A PASSING LOW TO THE NORTH. TEMPS WILL BE COOLER FRIDAY...BUT WILL WARM BACK TO A FEW DEGREES ABOVE NORMAL FOR SATURDAY. SATURDAY NIGHT THROUGH WEDNESDAY...FORECAST CONFIDENCE...MEDIUM COULD SEE SOME PRECIP AT TIMES FROM SATURDAY THROUGH TUESDAY...AS A SERIES OF SYSTEMS MOVE THROUGH A MAINLY STALLED FRONTAL ZONE. THERE REMAINS A BIT OF UNCERTAINTY WITH THIS PORTION OF THE FORECAST DUE TO MODEL DIFFERENCES IN FRONTAL PLACEMENT AND THUS TEMPS AND PRECIP CHANCES. IF THE FRONT SNEAKS FARTHER NORTH...WOULD EXPECT MUCH MILDER TEMPS AND A BETTER CHANCE FOR THUNDER. THE SOUTHERN SOLUTION WOULD RESULT IN PERSISTENT WINDS OFF THE LAKE...COOLER TEMPS...AND LESS INSTABILITY. CONTINUED THE DOWN THE MIDDLE APPROACH BETWEEN THE VARIOUS MODEL SOLUTIONS FOR NOW. LOOKS COOL AND DRY WEDNESDAY UNDER HIGH PRESSURE. AVIATION/12Z TAFS/... WILL MAKE SOME ADJUSTMENTS PRIOR TO ISSUANCE ON TIMING OF SHOWERS INTO TAF LOCATIONS AND THEIR IMPACT. EXPECT VFR CONDITIONS WITH ONLY BRIEF MVFR CIGS/VSBYS PER UPSTREAM OBSERVATIONS UNDER THE SHOWERS AND ISOLATED THUNDERSTORMS. HAVE KEPT MENTION OF ISOLATED THUNDERSTORMS THOUGH ELEVATED CAPE ALMOST NON-EXISTENT ON LATEST RAP FORECAST SOUNDINGS. HOWEVER... SPC MESOANALYSIS SHOWS AREA OF 500 J/KG MOST-UNSTABLE CAPE THAT COULD BRUSH SOUTHERN WISCONSIN SO CAN/T RULE OUT A RUMBLE OR TWO OF THUNDER. PCPN SHOULD CLEAR KMSN BY 18Z...AND EASTERN TAF SITES BETWEEN 20Z AND 21Z. LOOKING FOR VFR CONDITIONS THROUGH THE REMAINDER OF THE FORECAST. FIRE WEATHER... FIRE WEATHER CONDITIONS NOT AS CRITICAL AS YESTERDAY WITH EXPECTED 0.2 TO 0.3 INCH RAINFALLS MOISTENING FUELS. COOLER TEMPERATURES AND LOWER WINDS ALSO LOWERING THE THREAT...THOUGH LOWER DEW POINTS WILL BRING RELATIVE HUMIDITY VALUES DOWN TO AROUND 25 PERCENT IN THE WEST THIS AFTERNOON. MARINE... WILL KEEP CURRENT END TIME TO SMALL CRAFT ADVISORY AS WINDS ARE BEGINNING TO EASE WITH SLACKENING GRADIENT ASSOCIATED WITH SURFACE TROUGH. LOWERING WINDS AND VEERING TO AN OFFSHORE DIRECTION AFTER PASSAGE OF SURFACE TROUGH WILL ALLOW WAVES TO SUBSIDE BELOW CRITERIA BY MID-MORNING. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...MRC TODAY/TONIGHT AND AVIATION/MARINE...REM FRIDAY THROUGH WEDNESDAY...DDV
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
118 PM MDT THU APR 2 2015 .UPDATE... ISSUED AT 116 PM MDT THU APR 2 2015 COLD FRONT HAS PUSHED THROUGH THE FRONT RANGE URBAN CORRIDOR WITH NORTHERLY WINDS AND TEMPERATURES COOLING. AS THE JET IS OVERHEAD AND UPLIFT FROM THE FRONT OCCURS....SOME SHOWERS ARE INCREASING IN INTENSITY. A CELL JUST EAST OF DENVER INTERNATIONAL AIRPORT HAS SEVERAL IN CLOUD AND CLOUD TO GROUND LIGHTNING FLASHES CURRENTLY. SHORT TERM MODELS SHOW THIS CELL PUSHING EAST INTO WASHINGTON COUNTY THEN MORE WIDESPREAD PRECIPITATION MOVING IN FROM THE NORTH ACROSS THE CORRIDOR AND PLAINS OVER THE NEXT SEVERAL HOURS. UPDATE ISSUED AT 1105 AM MDT THU APR 2 2015 SYSTEM IS TRENDING A BIT FURTHER NORTH AS THE HRRR AND RUC WERE DENOTING. MOST SHOWERS OVER THE PLAINS ARE NOW NORTH OF DENVER WITH WARMING TEMPERATURES CHANGING SNOW OVER TO RAIN. HAVE UPDATED FORECAST TO SHOW BETTER CHANCE OVER THE NORTH FOR NOW. FORECASTING SNOWFALL AMOUNTS FOR THIS STORM CONTINUES TO BE QUITE DIFFICULT. A POINT OF CONCERN IS A DRY SLOT EVIDENT ON WATER VAPOR FROM THE SOUTHERN GREAT BASIN MOVING INTO WESTERN COLORADO RIGHT NOW. THIS COULD LIMIT THE SNOWFALL AMOUNTS EXPECTED LATER TODAY INTO TONIGHT. ALSO...LOOKING AT QG VERTICAL VELOCITY TRENDS...LIFT SEEMS TO DECREASE QUITE RAPIDLY AFTER 00Z. HRRR AND RUC PRECIPITATION TRENDS HAVE SHOWN A DECREASE OVER THE PLAINS AFTER 06Z...WILL CONTINUE FOLLOWING THEIR GUIDANCE HOWEVER QUITE A FEW DIFFERENCES RUN TO RUN. WARMING TEMPERATURES AND SOME CLEARING OVER THE SOUTHERN PART OF THE FORECAST AREA AS THE DAY MOVES ON WILL CHANGE PRECIP OVER THE RAIN AND MAY FURTHER HEAT THE GROUND AND THEREFORE LIMIT WHAT SNOW WILL STICK TO THE GROUND LATER. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 351 AM MDT THU APR 2 2015 WATER VAPOR SATELLITE IMAGERY IS SHOWING AN UPPER LEVEL TROUGH MOVING ACROSS NEVADA AT THIS TIME. IN ADDITION TO THE TROUGH...CAN SEE CLOUD ENHANCEMENT OVER UTAH AND NORTHWEST COLORADO THAT IS ASSOCIATED WITH THE LEFT EXIT REGION OF THE JET. AS THIS SYSTEM SHIFTS EASTWARD TODAY...IT WILL BRING MOSTLY SNOW TO NORTHEAST COLORADO. IT APPEARS THIS SYSTEM IS A LITTLE BIT FARTHER NORTH THAN FORECASTED 24 HOURS AGO. EVEN THE LATEST HRRR AND RAP CONTINUE THE TREND NORTHWARD WHERE THE MAIN PRECIPITATION IS STILL NORTH OF DENVER THROUGH MOST OF THE AFTERNOON. COLD AIR IS EXPECTED TO REMAIN ALONG THE FRONT RANGE THIS MORNING DUE TO EASTERLY UPSLOPE WINDS...KEEPING THE CHANCE FOR A RAIN SNOW MIX. NORTHERLY WINDS WILL INCREASE THIS AFTERNOON AS A SURFACE LOW DEEPENS OVER SOUTHERN COLORADO. EXPECT ENOUGH COLD AIR BEHIND THE NORTHERLY SURGE FOR PRECIPITATION TO CHANGE ALL TO SNOW WITH TEMPERATURES HOVERING AROUND FREEZING. RIGHT NOW ITS LOOKING LIKE THE BEST LIFT WILL BE FROM DENVER NORTH...SO WILL HAVE TO THE HIGHEST POPS THIS AFTERNOON FOR THIS AREA. PRECIPITATION IS EXPECTED TO SPREAD SOUTH AND EAST THIS EVENING AS UPSLOPE DEEPENS AND LIFT ALOFT SPREADS EAST. WITH THIS SYSTEM BEING QUICK MOVING AND TRENDING A LITTLE FARTHER NORTH...EXPECT SNOWFALL AMOUNTS TO REMAIN BELOW ADVISORY CRITERIA EVEN IN THE NORTHERN FOOTHILLS AND MOUNTAINS. SNOWFALL AMOUNTS OF 3 TO 7 IS EXPECTED IN THE FOOTHILLS WITH 1 TO 5 INCHES ALONG THE FRONT RANGE AND PARTS OF THE PLAINS. HEAVY AMOUNTS WILL BE FOUND TO THE NORTH. DUE TO APRIL SUN AND WARM GROUND TEMPERATURES...MOST OF THE ACCUMULATION SHOULD OCCUR ON GRASSY SURFACES. SOME SLUSHY ROADS WILL BE POSSIBLE UNDER THE AREAS OF HEAVIER SNOW AND ALSO THIS EVENING AS TEMPERATURES COOL. SNOW IS EXPECTED TO DECREASE LATE THIS EVENING AS THIS SYSTEM MOVES EAST OF THE REGION. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 351 AM MDT THU APR 2 2015 THE UPPER LEVEL TROUGH WILL MOVE EAST BY FRIDAY AFTERNOON WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NW. THIS WILL HELP TO TURN WINDS MORE WESTERLY THAT WILL AID IN INCREASING DOWNSLOPE BRINGING PRECIPITATION TO AN END. ISOLATED SHOWERS WILL STILL LINGER INTO FRIDAY MORNING BUT WILL QUICKLY DIMINISH BY THE AFTERNOON. MID LEVEL MOISTURE WILL DEGRADE THROUGH THE DAY WITH COOLER AIR STICKING AROUND KEEPING HIGHS ON FRIDAY IN THE 40S. TEMPERATURES WILL REBOUND TO ABOVE NORMAL FOR THE WEEKEND WITH UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE IN PLACE. HIGHS ON SATURDAY WILL GET INTO THE LOWER 60S WITH SUNDAY HAVING THE POTENTIAL OF LOWER 70S UNDER MOSTLY SUNNY SKIES. SUNDAY NIGHT INTO MONDAY UPPER LEVEL FLOW WILL SWITCH FROM WESTERLY TO SOUTHWESTERLY AHEAD OF THE NEXT UPPER LEVEL TROUGH. A WEAK TROUGH WILL PUSH THROUGH MONDAY AFTERNOON BRINGING COOLER TEMPERATURES AND INCREASING CLOUDS TO THE REGION. FOR TUESDAY INTO WEDNESDAY A ELONGATED UPPER LEVEL TROUGH WILL BE OVER THE PACIFIC NW MOVING EAST INTO THE GREAT BASIN. THIS WILL BRING A SLIGHT CHANCE OF PRECIPITATION TO NE COLORADO TUESDAY EVENING THROUGH WEDNESDAY. DETAILS ARE SCARCE AS THIS SYSTEM IS STILL A FEW DAYS AWAY BUT WILL CONTINUE TO MONITOR MODEL TRENDS. && .AVIATION...(FOR THE TAFS THROUGH 00Z FRIDAY LATE AFTERNOON) ISSUED AT 1221 PM MDT THU APR 2 2015 SURFACE LOW IS WRAPPING UP JUST SOUTHWEST OF KDEN WITH INCREASING WINDSPEEDS INTO IT. THIS LOW IS EXPECTED TO MOVE SLOWLY SOUTH- SOUTHEAST TURNING ALL AIRPORTS TO NORTH-NORTHWESTERLY WINDS LIKELY WITHIN THE NEXT HOUR. CEILINGS OF 2000 TO 4000 FEET WILL CONTINUE AROUND BJC AND DEN...WITH SOME CLEARING NEAR APA. MOSTLY RAIN SHOWERS FOR KDEN AND KAPA WITH SNOW ALREADY FOR KBJC. COLD AIR WILL LIKELY BEGIN TO MOVE DOWN IN THE NORTHERLY WINDS TO INCREASE WITH GUSTS TO 30 KNOTS POSSIBLE. THIS WILL COOL THE AIRMASS ENOUGH THAT PRECIPITATION IS EXPECTED TO QUICKLY TURN TO SNOW NEAR KAPA AND KDEN BY 21Z. BEST CHANCE FOR SNOW WILL BE DURING ABOUT 00Z TO 06Z. EXPECT VISIBILITY TO BE AROUND A MILE IN THE SNOW AND OCCASIONALLY FALL TO A QUARTER MILE UNDER THE HEAVIER SNOW. CONDITIONS ARE EXPECTED TO IMPROVE AFTER 06Z AS THIS SYSTEM STARTS TO SHIFT OFF TO THE EAST. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KRIEDERMAN SHORT TERM...MEIER LONG TERM...BOWEN AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1222 PM MDT THU APR 2 2015 .UPDATE... ISSUED AT 1105 AM MDT THU APR 2 2015 SYSTEM IS TRENDING A BIT FURTHER NORTH AS THE HRRR AND RUC WERE DENOTING. MOST SHOWERS OVER THE PLAINS ARE NOW NORTH OF DENVER WITH WARMING TEMPERATURES CHANGING SNOW OVER TO RAIN. HAVE UPDATED FORECAST TO SHOW BETTER CHANCE OVER THE NORTH FOR NOW. FORECASTING SNOWFALL AMOUNTS FOR THIS STORM CONTINUES TO BE QUITE DIFFICULT. A POINT OF CONCERN IS A DRY SLOT EVIDENT ON WATER VAPOR FROM THE SOUTHERN GREAT BASIN MOVING INTO WESTERN COLORADO RIGHT NOW. THIS COULD LIMIT THE SNOWFALL AMOUNTS EXPECTED LATER TODAY INTO TONIGHT. ALSO...LOOKING AT QG VERTICAL VELOCITY TRENDS...LIFT SEEMS TO DECREASE QUITE RAPIDLY AFTER 00Z. HRRR AND RUC PRECIPITATION TRENDS HAVE SHOWN A DECREASE OVER THE PLAINS AFTER 06Z...WILL CONTINUE FOLLOWING THEIR GUIDANCE HOWEVER QUITE A FEW DIFFERENCES RUN TO RUN. WARMING TEMPERATURES AND SOME CLEARING OVER THE SOUTHERN PART OF THE FORECAST AREA AS THE DAY MOVES ON WILL CHANGE PRECIP OVER THE RAIN AND MAY FURTHER HEAT THE GROUND AND THEREFORE LIMIT WHAT SNOW WILL STICK TO THE GROUND LATER. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 351 AM MDT THU APR 2 2015 WATER VAPOR SATELLITE IMAGERY IS SHOWING AN UPPER LEVEL TROUGH MOVING ACROSS NEVADA AT THIS TIME. IN ADDITION TO THE TROUGH...CAN SEE CLOUD ENHANCEMENT OVER UTAH AND NORTHWEST COLORADO THAT IS ASSOCIATED WITH THE LEFT EXIT REGION OF THE JET. AS THIS SYSTEM SHIFTS EASTWARD TODAY...IT WILL BRING MOSTLY SNOW TO NORTHEAST COLORADO. IT APPEARS THIS SYSTEM IS A LITTLE BIT FARTHER NORTH THAN FORECASTED 24 HOURS AGO. EVEN THE LATEST HRRR AND RAP CONTINUE THE TREND NORTHWARD WHERE THE MAIN PRECIPITATION IS STILL NORTH OF DENVER THROUGH MOST OF THE AFTERNOON. COLD AIR IS EXPECTED TO REMAIN ALONG THE FRONT RANGE THIS MORNING DUE TO EASTERLY UPSLOPE WINDS...KEEPING THE CHANCE FOR A RAIN SNOW MIX. NORTHERLY WINDS WILL INCREASE THIS AFTERNOON AS A SURFACE LOW DEEPENS OVER SOUTHERN COLORADO. EXPECT ENOUGH COLD AIR BEHIND THE NORTHERLY SURGE FOR PRECIPITATION TO CHANGE ALL TO SNOW WITH TEMPERATURES HOVERING AROUND FREEZING. RIGHT NOW ITS LOOKING LIKE THE BEST LIFT WILL BE FROM DENVER NORTH...SO WILL HAVE TO THE HIGHEST POPS THIS AFTERNOON FOR THIS AREA. PRECIPITATION IS EXPECTED TO SPREAD SOUTH AND EAST THIS EVENING AS UPSLOPE DEEPENS AND LIFT ALOFT SPREADS EAST. WITH THIS SYSTEM BEING QUICK MOVING AND TRENDING A LITTLE FARTHER NORTH...EXPECT SNOWFALL AMOUNTS TO REMAIN BELOW ADVISORY CRITERIA EVEN IN THE NORTHERN FOOTHILLS AND MOUNTAINS. SNOWFALL AMOUNTS OF 3 TO 7 IS EXPECTED IN THE FOOTHILLS WITH 1 TO 5 INCHES ALONG THE FRONT RANGE AND PARTS OF THE PLAINS. HEAVY AMOUNTS WILL BE FOUND TO THE NORTH. DUE TO APRIL SUN AND WARM GROUND TEMPERATURES...MOST OF THE ACCUMULATION SHOULD OCCUR ON GRASSY SURFACES. SOME SLUSHY ROADS WILL BE POSSIBLE UNDER THE AREAS OF HEAVIER SNOW AND ALSO THIS EVENING AS TEMPERATURES COOL. SNOW IS EXPECTED TO DECREASE LATE THIS EVENING AS THIS SYSTEM MOVES EAST OF THE REGION. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 351 AM MDT THU APR 2 2015 THE UPPER LEVEL TROUGH WILL MOVE EAST BY FRIDAY AFTERNOON WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NW. THIS WILL HELP TO TURN WINDS MORE WESTERLY THAT WILL AID IN INCREASING DOWNSLOPE BRINGING PRECIPITATION TO AN END. ISOLATED SHOWERS WILL STILL LINGER INTO FRIDAY MORNING BUT WILL QUICKLY DIMINISH BY THE AFTERNOON. MID LEVEL MOISTURE WILL DEGRADE THROUGH THE DAY WITH COOLER AIR STICKING AROUND KEEPING HIGHS ON FRIDAY IN THE 40S. TEMPERATURES WILL REBOUND TO ABOVE NORMAL FOR THE WEEKEND WITH UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE IN PLACE. HIGHS ON SATURDAY WILL GET INTO THE LOWER 60S WITH SUNDAY HAVING THE POTENTIAL OF LOWER 70S UNDER MOSTLY SUNNY SKIES. SUNDAY NIGHT INTO MONDAY UPPER LEVEL FLOW WILL SWITCH FROM WESTERLY TO SOUTHWESTERLY AHEAD OF THE NEXT UPPER LEVEL TROUGH. A WEAK TROUGH WILL PUSH THROUGH MONDAY AFTERNOON BRINGING COOLER TEMPERATURES AND INCREASING CLOUDS TO THE REGION. FOR TUESDAY INTO WEDNESDAY A ELONGATED UPPER LEVEL TROUGH WILL BE OVER THE PACIFIC NW MOVING EAST INTO THE GREAT BASIN. THIS WILL BRING A SLIGHT CHANCE OF PRECIPITATION TO NE COLORADO TUESDAY EVENING THROUGH WEDNESDAY. DETAILS ARE SCARCE AS THIS SYSTEM IS STILL A FEW DAYS AWAY BUT WILL CONTINUE TO MONITOR MODEL TRENDS. && .AVIATION...(FOR THE TAFS THROUGH 00Z FRIDAY LATE AFTERNOON) ISSUED AT 1221 PM MDT THU APR 2 2015 SURFACE LOW IS WRAPPING UP JUST SOUTHWEST OF KDEN WITH INCREASING WINDSPEEDS INTO IT. THIS LOW IS EXPECTED TO MOVE SLOWLY SOUTH- SOUTHEAST TURNING ALL AIRPORTS TO NORTH-NORTHWESTERLY WINDS LIKELY WITHIN THE NEXT HOUR. CEILINGS OF 2000 TO 4000 FEET WILL CONTINUE AROUND BJC AND DEN...WITH SOME CLEARING NEAR APA. MOSTLY RAIN SHOWERS FOR KDEN AND KAPA WITH SNOW ALREADY FOR KBJC. COLD AIR WILL LIKELY BEGIN TO MOVE DOWN IN THE NORTHERLY WINDS TO INCREASE WITH GUSTS TO 30 KNOTS POSSIBLE. THIS WILL COOL THE AIRMASS ENOUGH THAT PRECIPITATION IS EXPECTED TO QUICKLY TURN TO SNOW NEAR KAPA AND KDEN BY 21Z. BEST CHANCE FOR SNOW WILL BE DURING ABOUT 00Z TO 06Z. EXPECT VISIBILITY TO BE AROUND A MILE IN THE SNOW AND OCCASIONALLY FALL TO A QUARTER MILE UNDER THE HEAVIER SNOW. CONDITIONS ARE EXPECTED TO IMPROVE AFTER 06Z AS THIS SYSTEM STARTS TO SHIFT OFF TO THE EAST. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KRIEDERMAN SHORT TERM...MEIER LONG TERM...BOWEN AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1105 AM MDT THU APR 2 2015 .UPDATE... ISSUED AT 1105 AM MDT THU APR 2 2015 SYSTEM IS TRENDING A BIT FURTHER NORTH AS THE HRRR AND RUC WERE DENOTING. MOST SHOWERS OVER THE PLAINS ARE NOW NORTH OF DENVER WITH WARMING TEMPERATURES CHANGING SNOW OVER TO RAIN. HAVE UPDATED FORECAST TO SHOW BETTER CHANCE OVER THE NORTH FOR NOW. FORECASTING SNOWFALL AMOUNTS FOR THIS STORM CONTINUES TO BE QUITE DIFFICULT. A POINT OF CONCERN IS A DRY SLOT EVIDENT ON WATER VAPOR FROM THE SOUTHERN GREAT BASIN MOVING INTO WESTERN COLORADO RIGHT NOW. THIS COULD LIMIT THE SNOWFALL AMOUNTS EXPECTED LATER TODAY INTO TONIGHT. ALSO...LOOKING AT QG VERTICAL VELOCITY TRENDS...LIFT SEEMS TO DECREASE QUITE RAPIDLY AFTER 00Z. HRRR AND RUC PRECIPITATION TRENDS HAVE SHOWN A DECREASE OVER THE PLAINS AFTER 06Z...WILL CONTINUE FOLLOWING THEIR GUIDANCE HOWEVER QUITE A FEW DIFFERENCES RUN TO RUN. WARMING TEMPERATURES AND SOME CLEARING OVER THE SOUTHERN PART OF THE FORECAST AREA AS THE DAY MOVES ON WILL CHANGE PRECIP OVER THE RAIN AND MAY FURTHER HEAT THE GROUND AND THEREFORE LIMIT WHAT SNOW WILL STICK TO THE GROUND LATER. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 351 AM MDT THU APR 2 2015 WATER VAPOR SATELLITE IMAGERY IS SHOWING AN UPPER LEVEL TROUGH MOVING ACROSS NEVADA AT THIS TIME. IN ADDITION TO THE TROUGH...CAN SEE CLOUD ENHANCEMENT OVER UTAH AND NORTHWEST COLORADO THAT IS ASSOCIATED WITH THE LEFT EXIT REGION OF THE JET. AS THIS SYSTEM SHIFTS EASTWARD TODAY...IT WILL BRING MOSTLY SNOW TO NORTHEAST COLORADO. IT APPEARS THIS SYSTEM IS A LITTLE BIT FARTHER NORTH THAN FORECASTED 24 HOURS AGO. EVEN THE LATEST HRRR AND RAP CONTINUE THE TREND NORTHWARD WHERE THE MAIN PRECIPITATION IS STILL NORTH OF DENVER THROUGH MOST OF THE AFTERNOON. COLD AIR IS EXPECTED TO REMAIN ALONG THE FRONT RANGE THIS MORNING DUE TO EASTERLY UPSLOPE WINDS...KEEPING THE CHANCE FOR A RAIN SNOW MIX. NORTHERLY WINDS WILL INCREASE THIS AFTERNOON AS A SURFACE LOW DEEPENS OVER SOUTHERN COLORADO. EXPECT ENOUGH COLD AIR BEHIND THE NORTHERLY SURGE FOR PRECIPITATION TO CHANGE ALL TO SNOW WITH TEMPERATURES HOVERING AROUND FREEZING. RIGHT NOW ITS LOOKING LIKE THE BEST LIFT WILL BE FROM DENVER NORTH...SO WILL HAVE TO THE HIGHEST POPS THIS AFTERNOON FOR THIS AREA. PRECIPITATION IS EXPECTED TO SPREAD SOUTH AND EAST THIS EVENING AS UPSLOPE DEEPENS AND LIFT ALOFT SPREADS EAST. WITH THIS SYSTEM BEING QUICK MOVING AND TRENDING A LITTLE FARTHER NORTH...EXPECT SNOWFALL AMOUNTS TO REMAIN BELOW ADVISORY CRITERIA EVEN IN THE NORTHERN FOOTHILLS AND MOUNTAINS. SNOWFALL AMOUNTS OF 3 TO 7 IS EXPECTED IN THE FOOTHILLS WITH 1 TO 5 INCHES ALONG THE FRONT RANGE AND PARTS OF THE PLAINS. HEAVY AMOUNTS WILL BE FOUND TO THE NORTH. DUE TO APRIL SUN AND WARM GROUND TEMPERATURES...MOST OF THE ACCUMULATION SHOULD OCCUR ON GRASSY SURFACES. SOME SLUSHY ROADS WILL BE POSSIBLE UNDER THE AREAS OF HEAVIER SNOW AND ALSO THIS EVENING AS TEMPERATURES COOL. SNOW IS EXPECTED TO DECREASE LATE THIS EVENING AS THIS SYSTEM MOVES EAST OF THE REGION. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 351 AM MDT THU APR 2 2015 THE UPPER LEVEL TROUGH WILL MOVE EAST BY FRIDAY AFTERNOON WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NW. THIS WILL HELP TO TURN WINDS MORE WESTERLY THAT WILL AID IN INCREASING DOWNSLOPE BRINGING PRECIPITATION TO AN END. ISOLATED SHOWERS WILL STILL LINGER INTO FRIDAY MORNING BUT WILL QUICKLY DIMINISH BY THE AFTERNOON. MID LEVEL MOISTURE WILL DEGRADE THROUGH THE DAY WITH COOLER AIR STICKING AROUND KEEPING HIGHS ON FRIDAY IN THE 40S. TEMPERATURES WILL REBOUND TO ABOVE NORMAL FOR THE WEEKEND WITH UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE IN PLACE. HIGHS ON SATURDAY WILL GET INTO THE LOWER 60S WITH SUNDAY HAVING THE POTENTIAL OF LOWER 70S UNDER MOSTLY SUNNY SKIES. SUNDAY NIGHT INTO MONDAY UPPER LEVEL FLOW WILL SWITCH FROM WESTERLY TO SOUTHWESTERLY AHEAD OF THE NEXT UPPER LEVEL TROUGH. A WEAK TROUGH WILL PUSH THROUGH MONDAY AFTERNOON BRINGING COOLER TEMPERATURES AND INCREASING CLOUDS TO THE REGION. FOR TUESDAY INTO WEDNESDAY A ELONGATED UPPER LEVEL TROUGH WILL BE OVER THE PACIFIC NW MOVING EAST INTO THE GREAT BASIN. THIS WILL BRING A SLIGHT CHANCE OF PRECIPITATION TO NE COLORADO TUESDAY EVENING THROUGH WEDNESDAY. DETAILS ARE SCARCE AS THIS SYSTEM IS STILL A FEW DAYS AWAY BUT WILL CONTINUE TO MONITOR MODEL TRENDS. && .AVIATION...(FOR THE TAFS THROUGH 18Z FRIDAY MORNING) ISSUED AT 1105 AM MDT THU APR 2 2015 CEILINGS OF 2000 TO 4000 FEET WILL CONTINUE AROUND BJC AND DEN...WITH SOME CLEARING NEAR APA. MOSTLY RAIN SHOWERS FOR THE REST OF THE MORNING AND EARLY AFTERNOON BEFORE THE EXPECTED COLD FRONT....AROUND 20Z TO 22Z...CAUSES NORTHERLY WINDS TO INCREASE WITH GUSTS TO 30 KNOTS POSSIBLE. THIS WILL COOL THE AIRMASS ENOUGH THAT PRECIPITATION IS EXPECTED TO QUICKLY TURN TO SNOW BEHIND THE FRONT. BEST CHANCE FOR SNOW WILL BE DURING ABOUT 00Z TO 06Z. EXPECT VISIBILITY TO BE AROUND A MILE IN THE SNOW AND OCCASIONALLY FALL TO A QUARTER MILE UNDER THE HEAVIER SNOW. CONDITIONS ARE EXPECTED TO IMPROVE AFTER 06Z AS THIS SYSTEM STARTS TO SHIFT OFF TO THE EAST. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KRIEDERMAN SHORT TERM...MEIER LONG TERM...BOWEN AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
402 PM EDT THU APR 2 2015 .SYNOPSIS... LOW PRESSURE MOVING ACROSS EASTERN CANADA WILL CAUSE A FRONT TO APPROACH FROM THE WEST TONIGHT AND FRIDAY. AN AREA OF LOW PRESSURE DEVELOPING ON THE FRONT OVER THE OHIO VALLEY WILL CROSS OUR REGION FRIDAY NIGHT AND EARLY SATURDAY. HIGH PRESSURE WILL BUILD ACROSS THE AREA FOR THE WEEKEND AND INTO MONDAY. ANOTHER LOW PRESSURE SYSTEM AND ASSOCIATED FRONT WILL APPROACH NEXT TUESDAY. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... INTO THIS EVENING AND TONIGHT, A MID-LEVEL RIDGE AND SURFACE HIGH PRESSURE WILL CONTINUE TO ADVANCE EAST AND OFFSHORE. MEANWHILE, TO OUR WEST, A COLD FRONT EXTENDING FROM THE EASTERN GREAT LAKES AND DOWN NEAR THE OHIO VALLEY WILL CONTINUE TO GRADUALLY APPROACH OUR REGION. WITH THE APPROACH OF THIS SYSTEM, WE EXPECT INCREASING AND THICKENING CLOUD COVER INTO TONIGHT, ALONG WITH THE POSSIBILITY OF SOME SPRINKLES AND/OR LIGHT SHOWERS INTO PARTS OF EASTERN PA AND PERHAPS NORTHERN NJ. POPS WERE KEPT FAIRLY LOW THROUGH THE MID TO LATE EVENING BASED ON HRRR AND RAP GUIDANCE, FOLLOWED BY INCREASING POPS FROM WEST TO EAST DURING THE OVERNIGHT AND ESPECIALLY LEADING UP TO DAYBREAK AS STEADIER SHOWERS ARE PROGGED TO BE MOVING INTO OUR REGION AT THAT TIME. ELEVATED SOUTHWEST WINDS ARE EXPECTED TO CONTINUE THROUGH THE NIGHT, MOSTLY BETWEEN 15 TO 20 MPH, BUT A FEW GUSTS TO AROUND 25 MPH ARE NOT OUT OF THE QUESTION. WE TOOK A MET/MAV GUIDANCE BLEND WITH CONTINUITY FOR MINIMUM TEMPERATURES, AND WE EXPECT LOWS TO MAINLY RANGE FROM THE UPPER 40S NORTH TO THE MIDDLE 50S SOUTH. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/... THE PREVIOUSLY MENTIONED COLD FRONT WILL CONTINUE TO SLOWLY ADVANCE EAST TOWARD OUR REGION THROUGH THE DAYTIME FRIDAY, WITH INTERMITTENT SHOWERS EXPECTED. LIKELY TO CATEGORICAL POPS ARE IN PLACE FOR SHOWERS. WE HAVE ALSO KEPT SLIGHT CHANCE TO CHANCE MENTIONS OF THUNDER FOR A GOOD PORTION OF THE CWA, AS THERE WILL BE SOME INSTABILITY IN PLACE AHEAD OF THE APPROACHING BOUNDARY. DESPITE THE CLOUDS AND SHOWERS, ANOTHER MILD DAY IN EXPECTED, WITH THE CONTINUED SOUTH-SOUTHWEST FLOW. WE MAINLY BASED MAXIMUM TEMPERATURES ON A MET/MAV BLEND WITH CONTINUITY, AND WE ANTICIPATE HIGHS TO RANGE FROM AROUND 60 DEGREES IN PORTIONS OF THE SOUTHERN POCONOS TO THE LOWER 70S INTO THE SOUTHERN DELMARVA. && .LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/... A CONTINUATION OF SHOWERY CONDITIONS FRIDAY NIGHT AND EARLY SATURDAY AS A LOW PRESSURE SYSTEM MOVES ALONG THE FRONT WHICH WILL BE ACROSS THE AREA. WE WILL KEEP THE SMALL CHC FOR THUNDER IN THERE FOR FRI EVENING WITH SOME OF THE INSTABILITY INDICESPOINTING THAT WAY. POPS DECREASE OVERNIGHT WITH ONLY SLGT CHC POPS FOR SATURDAY WITH THE LINGERING H5 TROUGH MOVING THROUGH. SKY COVER IMPROVES TO SUNNY BY LATE AFTERNOON. TEMPERATURES ABOVE NORMAL FRI NIGHT AND BACK TO A FEW DEGREES BELOW NORMAL SATURDAY. FAIR WEATHER SAT NIGHT THROUGH MONDAY WITH HIGH PRESSURE IN CONTROL. A COUPLE SHOWERS ARE POSSIBLE SUN AFTERNOON AND SUN NIGHT ACROSS THE NORTHERN COUNTIES. CHC OR SLGT CHC POPS IS ALL THAT IS MENTIONED FOR NOW. TEMPERATURES WILL BE MOSTLY AROUND SEASONAL AVERAGES...ALTHOUGH READINGS WILL BE A BIT COOL SUN MORNING. ANOTHER FRONT AND WAVE OF LOW PRESSURE MOVING ALONG IT WILL AFFECT THE WEATHER FOR NEXT TUESDAY INTO THURSDAY. A COUPLE DAYS OF CLOUDS/SHOWERS ARE EXPECTED. A FEW TSTMS ARE ALSO POSSIBLE...BUT WE HAVE NOT PLACED THEM IN THE GRIDS THIS FAR OUT. POPS ARE GENERALLY LIKE THE WPC GRIDS...MOSTLY CHC POPS ATTM. TEMPERATURES WILL BE MOSTLY NEAR NORMAL. && .AVIATION /19Z THURSDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. LATE-DAY AND THIS EVENING...VFR CONDITIONS WILL CONTINUE, WITH SOME SCT CIRRUS THROUGH LATE-DAY, GIVING WAY TO A CEILING AROUND 10,000 FEET DEVELOPING DURING THE EVENING. GUSTY SOUTH-SOUTHWEST WINDS WILL CONTINUE, GUSTING TO AROUND 30 KTS THROUGH LATE-DAY AND THEN DIMINISHING A LITTLE, WITH GUSTS AVERAGING MORE AROUND 22 TO 25 KT THIS EVENING. OVERNIGHT...VFR CONDITIONS ARE ANTICIPATED TO HOLD THROUGH MOST OF THE OVERNIGHT, WITH CEILINGS LIKELY LOWERING TO MVFR AT MOST SITES TOWARD DAYBREAK AS SOME SCATTERED SHOWERS ADVANCE FROM WEST TO EAST ACROSS THE REGION. WE EXPECT SOUTH-SOUTHWEST WINDS TO REMAIN GUSTY THROUGH THE OVERNIGHT, WITH GUSTS MOSTLY BETWEEN 20 TO 23 KTS. MODEST LLWS APPEARS PROBABLE IN THE 03Z TO 08Z TIMEFRAME, BUT MOST OF THE 45 TO 50 KT WINDS ASSOCIATED WITH A LOW LEVEL JET LOOK TO BE ABOVE 2,000 FEET, AND WITH CONTINUED SURFACE WIND GUSTS DURING THIS PERIOD, LOW-LEVEL WIND SHEAR WAS NOT INCLUDED IN THE TAFS AT THIS TIME. FRIDAY...SOME INTERMITTENT SHOWERS ARE EXPECTED THROUGH THE DAY, ASSOCIATED WITH AN APPROACHING COLD FRONT. IN ADDITION, SOME THUNDER IS POSSIBLE AS WELL, BUT THE TIMING AND LOCATION OF ANY ISOLATED TO SCATTERED STORMS IS TOO UNCERTAIN AT THIS TIME TO INCLUDE IN THE TAFS. SOME STEADIER SHOWERS ARE ANTICIPATED THROUGH THE MORNING, AND WE KEPT ALL TAF SITES AT MVFR THROUGH THE MORNING, BEFORE SHOWERS BECOME MORE INTERMITTENT INTO THE AFTERNOON WITH SOME IMPROVEMENT IN CEILINGS POSSIBLE. MAINLY SOUTHWEST WINDS ARE EXPECTED, AVERAGING MOSTLY BETWEEN 8 TO 14 KNOTS. OUTLOOK... FRI NIGHT INTO EARLY SAT...LOW CLOUDS AND SHOWERS MAY REDUCE CIGS/VSBYS. SAT AFTERNOON THRU MONDAY...MOSTLY VFR. MON NIGHT THRU TUESDAY...LOWER CONDITIONS POSSIBLE. && .MARINE... WE CONTINUE WITH A SMALL CRAFT ADVISORY FOR OUR COASTAL WATERS AND FOR DELAWARE BAY THROUGH LATE FRIDAY NIGHT 10Z/SAT. SOUTH-SOUTHWEST WIND GUSTS IN ADVANCE OF AN APPROACHING COLD FRONT WILL LIKELY CONTINUE TO RANGE IN THE 25 TO 30KT PLUS AREA AT TIMES. SEAS WILL CONTINUE TO BUILD THROUGH THE DAYTIME FRIDAY, REACHING 5 TO 8 FEET FOR THE ATLANTIC COASTAL WATERS AND 3 TO 5 FEET IN DELAWARE BAY. OUTLOOK... FRI NIGHT THRU SATURDAY...SCA WINDS AND SEAS EXPECTED. SAT NIGHT AND SUNDAY...SCA SEAS ON THE OCEAN. SUB-SCA OVER DEL BAY. SUN NIGHT INTO MONDAY...SCA CONDITIONS EXPECTED. && .FIRE WEATHER... SOUTH TO SOUTHWEST WINDS OF TO 15 TO 20 MPH ARE OCCURRING THIS AFTERNOON. THERE WILL BE GUSTS OF 25 TO 35 MPH AT THAT TIME. ALSO, RELATIVE HUMIDITY VALUES ARE EXPECTED TO DROP TO BETWEEN 25-30 PERCENT AND FUEL MOISTURE LEVELS WILL BE ON THE DECREASE. THERE WILL BE AN ENHANCED THREAT OF RAPID WILDFIRE SPREAD INTO THE EARLY EVENING, EXCEPT FOR THOSE AREAS THAT STILL HAVE ANY SNOW COVER(N OF I-80). && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT SATURDAY FOR ANZ430-431- 450>455. && $$ SYNOPSIS...O`HARA NEAR TERM...KLINE SHORT TERM...KLINE LONG TERM...O`HARA AVIATION...KLINE/O`HARA MARINE...KLINE/O`HARA FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
651 PM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE WESTERN ATLANTIC THROUGH TONIGHT. A FAST MOVING COLD FRONT WILL CROSS THE REGION SATURDAY MORNING... FOLLOWED BY COOLER HIGH PRESSURE THROUGH SUNDAY. THE HIGH WILL SHIFT INTO THE ATLANTIC AND WILL PUSH WARMER AND MORE HUMID AIR INTO THE REGION THROUGH THE FIRST HALF OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... 02/21Z SURFACE AND RADAR DATA INDICATE THE SEA BREEZE HAS CLEARED THE FAR WESTERN ZONES AND ENTERED EAST-CENTRAL GEORGIA. SHOWER ACTIVITY HAS ESSENTIALLY ENDED ACROSS INTERIOR SOUTHEAST GEORGIA EXCEPT FOR THE REMNANTS OF AN EARLIER STRONG THUNDERSTORM WHICH ARE MOVING INTO ALLENDALE COUNTY. HIGH RESOLUTION DATA SUGGEST THE SEA BREEZE WILL INTERACT WITH A PRONOUNCED OUTFLOW BOUNDARY THAT IS CURRENTLY PROPAGATING EAST OVER SOUTH-CENTRAL GEORGIA TO PRODUCE ANOTHER AROUND OF ISOLATED TO SCATTERED SHOWERS AND TSTMS LATER THIS EVENING. THIS ACTIVITY LOOKS TO REMAIN CONFINED TO THE FAR WESTERN PORTIONS OF THE FORECAST AREA WHERE RAP INSTABILITY PROGNOSTICATIONS KEEP WEAK INSTABILITY (SBCAPE AROUND 1000 J/KG WITH LI`S OF -2 TO -4C) IN PLACE FOR MUCH OF THE EARLY-MID EVENING HOURS. AN ISOLATED STRONG TO SEVERE TSTM CAN NOT BE COMPLETELY RULED OUT WITH LOW WBZ HEIGHTS JUXTAPOSED WITH 0-6KM BULK SHEAR OF 20-25 KT. 02/18Z DATA ARE NOT OVERLY IMPRESSIVE WITH THE FOG POTENTIAL OVERNIGHT...ALTHOUGH SATELLITE DERIVED CLOUD PRODUCTS DO SHOW CLOUDS THINNING LATER THIS EVENING AS DIURNAL CUMULUS DISSIPATES AND THE BAND OF CIRRUS MOVING OVERHEAD PUSHES EAST/NORTHEAST. SUSPECT THE FOG WILL BE RATHER SHALLOW WITH THE BEST CHANCES CONFINED TO AREAS WEST OF I-95 AND ESPECIALLY OVER INTERIOR SOUTHEAST GEORGIA. WILL ADJUST SKY COVER DOWN THIS EVENING INTO THE EARLY MORNING HOURS FRIDAY WITH COVERAGE INCREASING LATE...ALTHOUGH CONFIDENCE ON EXACTLY HOW MUCH CLOUD COVER WILL BE AROUND IS RATHER LOW. LOWS IN THE LOWER 60S LOOK REASONABLE. FOR THE EARLY EVENING UPDATE... * ADJUSTED POPS BASED ON SHORT TERM TRENDS. INCREASED POPS UP TO 30 PERCENT FOR AREAS ROUGHLY NORTH OF METTER-SAINT GEORGE LINE. HIGHER POPS MAY EVENTUALLY BE NEEDED PENDING LATER RADAR TRENDS. * ADJUSTED SKY COVER DOWN LATER THIS EVENING INTO THE EARLY MORNING HOURS FRIDAY. * DOWNGRADED THE AREAS OF FOG QUALIFIER TO PATCHY. * ADJUSTED HOURLY TEMPERATURES AND DEWPOINTS BASED ON A BLEND OF THE H3R/RAP. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... FRIDAY WILL BE WARM ACROSS MOST OF THE AREA AS SOUTHERLY TO SOUTHWESTERLY LOW LEVEL FLOW PREVAILS BETWEEN A HIGH PRESSURE RIDGE OVER THE WESTERN ATLANTIC AND AN APPROACHING COLD FRONT. THE EXCEPTION WILL BE NEAR THE COAST AS THE WINDS BECOME SOUTHERLY...AND EVEN SOUTH SOUTHEASTERLY ALONG THE GEORGIA COAST BEHIND A SEA BREEZE. HIGH TEMPERATURES WILL RANGE FROM THE LOWER TO MID 80S INLAND TO NEAR 70 AT THE BEACHES. AREAS NEAR THE COAST WHERE THE SEA BREEZE PASSES DURING THE AFTERNOON WILL TURN COOLER IN THE WAKE OF THE SEA BREEZE. THE OTHER POTENTIAL ISSUE FOR COASTAL LOCATIONS IS SEA FOG. WITH DEW POINTS RISING TO NEAR OR JUST ABOVE SEA SURFACE TEMPERATURES...A NEAR SURFACE INVERSION WILL BE PLACE OVER THE COOL COASTAL WATERS...AND WITH A FAVORABLE SOUTH TO SOUTHWEST FLOW...SEA FOG WILL BE POSSIBLE OVER THE COOLER SHELF WATERS. IT IS POSSIBLE THAT SOME OF THIS SEA FOG WILL SKIRT OR BRIEFLY MOVE INLAND ALONG THE IMMEDIATE COASTLINE IN THE WAKE OF THE SEA BREEZE FRIDAY AFTERNOON AND INTO THE EVENING. FRIDAY NIGHT...WINDS WILL BECOME SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT...ENSURING THAT ANY SEA FOG THAT MOVED INLAND WILL BE SHUNTED QUICKLY BACK OFFSHORE. THERE WILL ALSO BE AN INCREASE IN CLOUD COVER...ESPECIALLY LATE. MAINTAINED A MAINLY SLIGHT CHANCE OF PRECIPITATION IN THE NORTHWEST LATE. REMOVED MENTION OF THUNDER DURING THIS TIME FRAME AS THE ATMOSPHERE IS FAIRLY STABLE AND THE DECENT FORCING WITH THE FRONT WILL STILL BE WEST OF THE AREA. LOWS WILL BE QUITE MILD...MAINLY IN THE LOWER 60S. SATURDAY...THE COLD FRONT WILL PUSH THROUGH THE AREA QUICKLY ON SATURDAY. THERE WILL BE A CHANCE FOR SHOWERS MOST PLACES AS THE MAIN CONVERGENCE LINE MOVES THROUGH. THERE COULD ALSO BE A FEW ISOLATED THUNDERSTORMS AS SOME VERY WEAK INSTABILITY IS POSSIBLE ALONG AND JUST AHEAD OF THE FRONT. SKIES SHOULD CLEAR OUT FAIRLY QUICKLY BEHIND THE FRONT WITH MOST AREAS BECOMING SUNNY BY MID TO LATE AFTERNOON. HIGH TEMPERATURES SHOULD BE IN THE LOWER TO MID 70S. SATURDAY NIGHT...COOLER HIGH PRESSURE BUILDS IN BEHIND THE COLD FRONT...ALLOWING FOR CLEAR SKIES AND SOME GUSTY WINDS ALONG THE COAST. LOW TEMPS SUNDAY MORNING WILL BE 15 TO 20 DEGREES COOLER THAN SATURDAY MORNING....MAINLY IN THE 40S. SUNDAY...HIGH PRESSURE WILL SHIFT OFF THE MID ATLANTIC COAST... ALLOWING THE SURFACE WINDS TO BECOME EASTERLY BY LATE IN THE DAY. THE WINDS OFF THE OCEAN AND THE IMPACTS OF THE COOLER AIR MASS WILL KEEP TEMPERATURES DOWN A BIT...WITH HIGHS RANGING FROM THE UPPER 60S ALONG THE SOUTH CAROLINA COAST TO LOWER 70S ACROSS INTERIOR GEORGIA. THERE WILL BE INCREASING HIGH LEVEL CLOUD COVER DURING THE AFTERNOON IN ADVANCE OF A STORM SYSTEM IN THE LOWER MISSISSIPPI VALLEY. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... THE AREA WILL BE ON THE NORTH SIDE OF A PERSISTENT SURFACE RIDGE OVER FLORIDA NEXT WEEK AS A SERIES OF DISTURBANCES MOVES BY TO OUR NORTH ALONG A WAVY FRONT. WE WILL REMAIN ON THE WARM AND HUMID SIDE OF FRONT FOR THE MOST PART...SO TEMPS WILL REBOUND INTO THE 70S ON MONDAY AND 80S FOR THE MIDDLE OF THE WEEK. THE COAST WILL BE COOLER AS THE SOUTHWESTERLY WINDS TURN ONSHORE IN THE AFTERNOONS. AS THE DISTURBANCES PASS BY...THERE WILL BE SOME SCATTERED SHOWERS AND POSSIBLY THUNDERSTORMS...MAINLY EACH AFTERNOON/EVENING ALONG THE SEA BREEZE AS IT MOVES INLAND...BUT IT IS HARD TO PIN DOWN ANY ONE PARTICULAR DAY THAT MIGHT SEE MORE ACTIVITY. MOST OF THE TIME IT WILL BE DRY. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... VFR FOR MUCH OF THE NIGHT. HIGHER DEWPOINTS AND A LITTLE BETTER MODEL AGREEMENT SUPPORTS A PERIOD OF IFR CIGS AT KSAV JUST BEFORE SUNRISE FRIDAY...ROUGHLY 09-12Z. HOWEVER...CONFIDENCE ON THE EXACT TIMING AND COVERAGE REMAINS HIGHLY UNCERTAIN 10-12 HOURS OUT. A TEMPO GROUP FOR SCT004 BKN008 WILL BE UTILIZED TO ADDRESS THIS POTENTIAL FOR THE 00Z TAF CYCLE. CONFIDENCE FOR SUB-VFR CONDITIONS AT KCHS IS CONSIDERABLY LOWER WHERE GUIDANCE IS A BIT LESS UNIFORM. WILL GO WITH PREVAILING VFR THERE FOR NOW. VFR WILL PREVAIL AT BOTH TERMINALS AFTER SUNRISE THROUGH 04/00Z. EXTENDED AVIATION OUTLOOK...SCATTERED SHOWERS AND TSTMS EXPECTED SATURDAY WITH POSSIBLE SUB VFR CONDITIONS. OTHERWISE...MAINLY VFR. && .MARINE... TONIGHT...THE MARINE AREA WILL REMAIN ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH WINDS BECOMING SOUTH AND SOUTHWEST OVERNIGHT. THE SEA BREEZE WILL SLOWLY DIMINISH ALONG THE COAST THIS EVENING. WITH WINDS BECOMING SOUTHERLY AND DECREASING A BIT LATER TONIGHT WE COULD SEE PATCHY SEA FOG DEVELOP OFF THE GA COAST WHERE DEWPOINTS REMAIN IN THE LOWER 60S AND WATER TEMPS ARE IN THE UPPER 50S TO AROUND 60. ON FRIDAY...THERE WILL LIKELY BE PATCHES OF SEA FOG ACROSS THE COASTAL WATERS MAINLY WITHIN 15 MILES OF THE COAST. WITH THE DIFFERENCE BETWEEN SEAS SURFACE TEMPERATES AND DEW POINT TEMPERATURES RELATIVELY SMALL...THE CURRENT THINKING IS THAT DENSE SEA FOG IS UNLIKELY AND THAT IF ANY DENSE SEA FOG DEVELOPS IT BE PATCHY IN NATURE AND NOT PERSIST VERY LONG. SEAS WILL MAINLY BE FROM 2 TO 3 FEET ALONG WITH WINDS INCREASING TO 10 TO 15 KNOTS BY LATE IN THE DAY. ON FRIDAY NIGHT...WINDS SHOULD INCREASE A LITTLE...BUT STILL REMAIN AT OR BELOW 20 KNOTS. SEAS WILL RISE INTO THE 2 TO 4 FOOT RANGE. PATCHY SEA FOG IS EXPECTED TO PERSIST ACROSS THE COASTAL WATERS...ALTHOUGH THERE WILL BE A TENDENCY FOR THERE TO BE LESS SEA FOG LATE IN THE NIGHT AS WINDS BECOME MORE SOUTHWEST. MODEL TRENDS INDICATE THAT DEW POINT TEMPERATURES SHOULD DROP SOME LATE WHICH WOULD ALSO FAVOR LESS SEA FOG LATE. SATURDAY...THE COLD FRONT WILL MOVE THROUGH THE AREA. BEHIND THE FRONT...WINDS WILL TURN TO THE NORTHWEST...AND THEN NORTH...AND EVENTUALLY NORTHEAST SATURDAY NIGHT. EXPECT SMALL CRAFT ADVISORIES WILL BE NEEDED FOR MOST OF THE COASTAL WATERS BEHIND THE FRONT BY LATE SATURDAY OR SATURDAY NIGHT. SCA CONDITIONS ARE LIKELY TO CONTINUE INTO SUNDAY MORNING...AT LEAST FOR THE GEORGIA WATERS...BEFORE THE WINDS COME DOWN DURING THE AFTERNOON. SEAS WILL BE UP FOR A WHILE AS WELL DUE TO A DEVELOPING LONG NORTHEASTERLY FETCH OVER THE ATLANTIC. NEXT WEEK...WINDS SHOULD BE GENERALLY OUT OF THE SOUTHEAST OR SOUTH AT 15 KNOTS OR LESS AS ATLANTIC HIGH PRESSURE DOMINATES. SEAS WILL REMAIN SOMEWHAT ELEVATED DUE TO THE LONG FETCH. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
555 PM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE WESTERN ATLANTIC THROUGH TONIGHT. A FAST MOVING COLD FRONT WILL CROSS THE REGION SATURDAY MORNING... FOLLOWED BY COOLER HIGH PRESSURE THROUGH SUNDAY. THE HIGH WILL SHIFT INTO THE ATLANTIC AND WILL PUSH WARMER AND MORE HUMID AIR INTO THE REGION THROUGH THE FIRST HALF OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... 02/21Z SURFACE AND RADAR DATA INDICATE THE SEA BREEZE HAS CLEARED THE FAR WESTERN ZONES AND ENTERED EAST-CENTRAL GEORGIA. SHOWER ACTIVITY HAS ESSENTIALLY ENDED ACROSS INTERIOR SOUTHEAST GEORGIA EXCEPT FOR THE REMNANTS OF AN EARLIER STRONG THUNDERSTORM WHICH ARE MOVING INTO ALLENDALE COUNTY. HIGH RESOLUTION DATA SUGGEST THE SEA BREEZE WILL INTERACT WITH A PRONOUNCED OUTFLOW BOUNDARY THAT IS CURRENTLY PROPAGATING EAST OVER SOUTH-CENTRAL GEORGIA TO PRODUCE ANOTHER AROUND OF ISOLATED TO SCATTERED SHOWERS AND TSTMS LATER THIS EVENING. THIS ACTIVITY LOOKS TO REMAIN CONFINED TO THE FAR WESTERN PORTIONS OF THE FORECAST AREA WHERE RAP INSTABILITY PROGNOSTICATIONS KEEP WEAK INSTABILITY (SBCAPE AROUND 1000 J/KG WITH LI`S OF -2 TO -4C) IN PLACE FOR MUCH OF THE EARLY-MID EVENING HOURS. AN ISOLATED STRONG TO SEVERE TSTM CAN NOT BE COMPLETELY RULED OUT WITH LOW WBZ HEIGHTS JUXTAPOSED WITH 0-6KM BULK SHEAR OF 20-25 KT. 02/18Z DATA ARE NOT OVERLY IMPRESSIVE WITH THE FOG POTENTIAL OVERNIGHT...ALTHOUGH SATELLITE DERIVED CLOUD PRODUCTS DO SHOW CLOUDS THINNING LATER THIS EVENING AS DIURNAL CUMULUS DISSIPATES AND THE BAND OF CIRRUS MOVING OVERHEAD PUSHES EAST/NORTHEAST. SUSPECT THE FOG WILL BE RATHER SHALLOW WITH THE BEST CHANCES CONFINED TO AREAS WEST OF I-95 AND ESPECIALLY OVER INTERIOR SOUTHEAST GEORGIA. WILL ADJUST SKY COVER DOWN THIS EVENING INTO THE EARLY MORNING HOURS FRIDAY WITH COVERAGE INCREASING LATE...ALTHOUGH CONFIDENCE ON EXACTLY HOW MUCH CLOUD COVER WILL BE AROUND IS RATHER LOW. LOWS IN THE LOWER 60S LOOK REASONABLE. FOR THE EARLY EVENING UPDATE... * ADJUSTED POPS BASED ON SHORT TERM TRENDS. INCREASED POPS UP TO 30 PERCENT FOR AREAS ROUGHLY NORTH OF METTER-SAINT GEORGE LINE. HIGHER POPS MAY EVENTUALLY BE NEEDED PENDING LATER RADAR TRENDS. * ADJUSTED SKY COVER DOWN LATER THIS EVENING INTO THE EARLY MORNING HOURS FRIDAY. * DOWNGRADED THE AREAS OF FOG QUALIFIER TO PATCHY. * ADJUSTED HOURLY TEMPERATURES AND DEWPOINTS BASED ON A BLEND OF THE H3R/RAP. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... FRIDAY WILL BE WARM ACROSS MOST OF THE AREA AS SOUTHERLY TO SOUTHWESTERLY LOW LEVEL FLOW PREVAILS BETWEEN A HIGH PRESSURE RIDGE OVER THE WESTERN ATLANTIC AND AN APPROACHING COLD FRONT. THE EXCEPTION WILL BE NEAR THE COAST AS THE WINDS BECOME SOUTHERLY...AND EVEN SOUTH SOUTHEASTERLY ALONG THE GEORGIA COAST BEHIND A SEA BREEZE. HIGH TEMPERATURES WILL RANGE FROM THE LOWER TO MID 80S INLAND TO NEAR 70 AT THE BEACHES. AREAS NEAR THE COAST WHERE THE SEA BREEZE PASSES DURING THE AFTERNOON WILL TURN COOLER IN THE WAKE OF THE SEA BREEZE. THE OTHER POTENTIAL ISSUE FOR COASTAL LOCATIONS IS SEA FOG. WITH DEW POINTS RISING TO NEAR OR JUST ABOVE SEA SURFACE TEMPERATURES...A NEAR SURFACE INVERSION WILL BE PLACE OVER THE COOL COASTAL WATERS...AND WITH A FAVORABLE SOUTH TO SOUTHWEST FLOW...SEA FOG WILL BE POSSIBLE OVER THE COOLER SHELF WATERS. IT IS POSSIBLE THAT SOME OF THIS SEA FOG WILL SKIRT OR BRIEFLY MOVE INLAND ALONG THE IMMEDIATE COASTLINE IN THE WAKE OF THE SEA BREEZE FRIDAY AFTERNOON AND INTO THE EVENING. FRIDAY NIGHT...WINDS WILL BECOME SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT...ENSURING THAT ANY SEA FOG THAT MOVED INLAND WILL BE SHUNTED QUICKLY BACK OFFSHORE. THERE WILL ALSO BE AN INCREASE IN CLOUD COVER...ESPECIALLY LATE. MAINTAINED A MAINLY SLIGHT CHANCE OF PRECIPITATION IN THE NORTHWEST LATE. REMOVED MENTION OF THUNDER DURING THIS TIME FRAME AS THE ATMOSPHERE IS FAIRLY STABLE AND THE DECENT FORCING WITH THE FRONT WILL STILL BE WEST OF THE AREA. LOWS WILL BE QUITE MILD...MAINLY IN THE LOWER 60S. SATURDAY...THE COLD FRONT WILL PUSH THROUGH THE AREA QUICKLY ON SATURDAY. THERE WILL BE A CHANCE FOR SHOWERS MOST PLACES AS THE MAIN CONVERGENCE LINE MOVES THROUGH. THERE COULD ALSO BE A FEW ISOLATED THUNDERSTORMS AS SOME VERY WEAK INSTABILITY IS POSSIBLE ALONG AND JUST AHEAD OF THE FRONT. SKIES SHOULD CLEAR OUT FAIRLY QUICKLY BEHIND THE FRONT WITH MOST AREAS BECOMING SUNNY BY MID TO LATE AFTERNOON. HIGH TEMPERATURES SHOULD BE IN THE LOWER TO MID 70S. SATURDAY NIGHT...COOLER HIGH PRESSURE BUILDS IN BEHIND THE COLD FRONT...ALLOWING FOR CLEAR SKIES AND SOME GUSTY WINDS ALONG THE COAST. LOW TEMPS SUNDAY MORNING WILL BE 15 TO 20 DEGREES COOLER THAN SATURDAY MORNING....MAINLY IN THE 40S. SUNDAY...HIGH PRESSURE WILL SHIFT OFF THE MID ATLANTIC COAST... ALLOWING THE SURFACE WINDS TO BECOME EASTERLY BY LATE IN THE DAY. THE WINDS OFF THE OCEAN AND THE IMPACTS OF THE COOLER AIR MASS WILL KEEP TEMPERATURES DOWN A BIT...WITH HIGHS RANGING FROM THE UPPER 60S ALONG THE SOUTH CAROLINA COAST TO LOWER 70S ACROSS INTERIOR GEORGIA. THERE WILL BE INCREASING HIGH LEVEL CLOUD COVER DURING THE AFTERNOON IN ADVANCE OF A STORM SYSTEM IN THE LOWER MISSISSIPPI VALLEY. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... THE AREA WILL BE ON THE NORTH SIDE OF A PERSISTENT SURFACE RIDGE OVER FLORIDA NEXT WEEK AS A SERIES OF DISTURBANCES MOVES BY TO OUR NORTH ALONG A WAVY FRONT. WE WILL REMAIN ON THE WARM AND HUMID SIDE OF FRONT FOR THE MOST PART...SO TEMPS WILL REBOUND INTO THE 70S ON MONDAY AND 80S FOR THE MIDDLE OF THE WEEK. THE COAST WILL BE COOLER AS THE SOUTHWESTERLY WINDS TURN ONSHORE IN THE AFTERNOONS. AS THE DISTURBANCES PASS BY...THERE WILL BE SOME SCATTERED SHOWERS AND POSSIBLY THUNDERSTORMS...MAINLY EACH AFTERNOON/EVENING ALONG THE SEA BREEZE AS IT MOVES INLAND...BUT IT IS HARD TO PIN DOWN ANY ONE PARTICULAR DAY THAT MIGHT SEE MORE ACTIVITY. MOST OF THE TIME IT WILL BE DRY. && .AVIATION /22Z THURSDAY THROUGH TUESDAY/... ONSHORE MOISTURE FLUX WITH COOLING TEMPERATURES OVERNIGHT WILL COMBINE TO ALLOW FOR LOW STRATUS AT BOTH TERMINALS. WE HAVE A FEW HOURS OF MVFR CEILINGS LATE TONIGHT INTO FRI MORNING AT BOTH SITES. WE CANNOT RULE OUT A PERIOD OF IFR CEILINGS THOUGH THE HIGHEST PROBABILITIES FOR SUCH OCCURRENCE WILL BE INLAND OF BOTH SITES WHERE LOW-LEVEL WINDS WILL BE LIGHTER. EXTENDED AVIATION OUTLOOK...SCATTERED SHOWERS AND TSTMS EXPECTED SATURDAY WITH POSSIBLE SUB VFR CONDITIONS. OTHERWISE...MAINLY VFR. && .MARINE... TONIGHT...THE MARINE AREA WILL REMAIN ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH WINDS BECOMING SOUTH AND SOUTHWEST OVERNIGHT. THE SEA BREEZE WILL SLOWLY DIMINISH ALONG THE COAST THIS EVENING. WITH WINDS BECOMING SOUTHERLY AND DECREASING A BIT LATER TONIGHT WE COULD SEE PATCHY SEA FOG DEVELOP OFF THE GA COAST WHERE DEWPOINTS REMAIN IN THE LOWER 60S AND WATER TEMPS ARE IN THE UPPER 50S TO AROUND 60. ON FRIDAY...THERE WILL LIKELY BE PATCHES OF SEA FOG ACROSS THE COASTAL WATERS MAINLY WITHIN 15 MILES OF THE COAST. WITH THE DIFFERENCE BETWEEN SEAS SURFACE TEMPERATES AND DEW POINT TEMPERATURES RELATIVELY SMALL...THE CURRENT THINKING IS THAT DENSE SEA FOG IS UNLIKELY AND THAT IF ANY DENSE SEA FOG DEVELOPS IT BE PATCHY IN NATURE AND NOT PERSIST VERY LONG. SEAS WILL MAINLY BE FROM 2 TO 3 FEET ALONG WITH WINDS INCREASING TO 10 TO 15 KNOTS BY LATE IN THE DAY. ON FRIDAY NIGHT...WINDS SHOULD INCREASE A LITTLE...BUT STILL REMAIN AT OR BELOW 20 KNOTS. SEAS WILL RISE INTO THE 2 TO 4 FOOT RANGE. PATCHY SEA FOG IS EXPECTED TO PERSIST ACROSS THE COASTAL WATERS...ALTHOUGH THERE WILL BE A TENDENCY FOR THERE TO BE LESS SEA FOG LATE IN THE NIGHT AS WINDS BECOME MORE SOUTHWEST. MODEL TRENDS INDICATE THAT DEW POINT TEMPERATURES SHOULD DROP SOME LATE WHICH WOULD ALSO FAVOR LESS SEA FOG LATE. SATURDAY...THE COLD FRONT WILL MOVE THROUGH THE AREA. BEHIND THE FRONT...WINDS WILL TURN TO THE NORTHWEST...AND THEN NORTH...AND EVENTUALLY NORTHEAST SATURDAY NIGHT. EXPECT SMALL CRAFT ADVISORIES WILL BE NEEDED FOR MOST OF THE COASTAL WATERS BEHIND THE FRONT BY LATE SATURDAY OR SATURDAY NIGHT. SCA CONDITIONS ARE LIKELY TO CONTINUE INTO SUNDAY MORNING...AT LEAST FOR THE GEORGIA WATERS...BEFORE THE WINDS COME DOWN DURING THE AFTERNOON. SEAS WILL BE UP FOR A WHILE AS WELL DUE TO A DEVELOPING LONG NORTHEASTERLY FETCH OVER THE ATLANTIC. NEXT WEEK...WINDS SHOULD BE GENERALLY OUT OF THE SOUTHEAST OR SOUTH AT 15 KNOTS OR LESS AS ATLANTIC HIGH PRESSURE DOMINATES. SEAS WILL REMAIN SOMEWHAT ELEVATED DUE TO THE LONG FETCH. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
223 PM EDT THU APR 2 2015 .UPDATE... THE LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 240 AM EST THU APR 2 2015 UNSETTLED WEATHER EXPECTED THROUGH FRIDAY NIGHT AS A FRONTAL SYSTEM DROPS SOUTHEAST ACROSS THE OHIO VALLEY. THUNDERSTORMS WILL RETURN EARLY NEXT WEEK AS WELL WITH ANOTHER SYSTEM. THERE COULD BE A FEW SEVERE STORMS TODAY AND THIS EVENING AS WELL AS NEXT WEEK. HEAVY RAIN IS ALSO POSSIBLE AT TIMES THROUGH FRIDAY. MEANWHILE...HIGH PRESSURE WILL RESULT IN DRY BUT COOLER WEATHER SATURDAY AND SUNDAY. && .NEAR TERM /REST OF TODAY THROUGH FRIDAY NIGHT/... ISSUED AT 955 AM EDT THU APR 2 2015 UPDATE...DELAYED INCREASE OF SHOWERS AND THUNDERSTORMS A LITTLE THROUGH EARLY AFTERNOON BASED ON RADAR TRENDS AND RAPID REFRESH. ALSO DROPPED MENTION OF HEAVY RAINFALL UNTIL LATE AFTERNOON AND THEN ONLY MENTIONED IT OVER THE SOUTHERN 2/3 OF OUR REGION. TEMPERATURES AND THE REST OF THE NEAR TERM IS ON TRACK AND ONLY MINOR TWEAKS MADE TO GRIDS IN REST OF FORECAST. PREVIOUS NEAR TERM DISCUSSION FOLLOWS... MAIN FOCUS FOR THE NEAR TERM WILL BE THUNDERSTORMS TODAY THROUGH FRIDAY ALONG WITH POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND EVENING AND HEAVY RAIN THIS AFTERNOON THROUGH FRIDAY. DETERMINISTIC MODELS STILL HAVE TIMING DIFFERENCES REGARDING UPPER AND SURFACE WAVES AND CONSEQUENTLY TIMING OF THE COLD FRONT...THAT WAS OVER THE UPPER MIDWEST AND SOUTHERN PLAINS THIS OVERNIGHT. HOWEVER...THE DIFFERENCES IN THE 00Z RUN THIS EVENING...SAVE THE NAM...ARE NOT AS GREAT AS THEY ONCE WERE. THE 00Z GFS IS TRENDING FURTHER NORTH WITH ITS TRACK OF SURFACE WAVES AND THEREFORE FRONTAL POSITION ON FRIDAY PER THE STEADIER 12Z ECMWF. A FEW GEFS MEMBERS WERE CLOSE TO THE OPERATIONAL 12Z ECMWF AS WAS ECMWF ENSEMBLE MEAN. MEANWHILE...THE 00Z CANADIAN IS A BIT QUICKER WITH THE FRONT...ALBEIT SLOWER WITH THE UPSTREAM TROUGH. OVERALL...FEEL A BLEND OF THE 00Z GFS...12Z ECMWF AND 12Z ECENS LOOKS BEST. THE COLD FRONT SHOULD DROP SOUTHEAST TO NEAR MERRIVILLE AROUND 18Z THIS AFTERNOON...TO FAR NORTHERN PARTS OF CENTRAL INDIANA 00Z THIS EVENING...AND TO NEAR THE OHIO RIVER ON FRIDAY...BEFORE IT TEMPORARILY STALLS WITH THE WAVES MOVING ALONG IT. FINALLY...THE FRONT SHOULD MOVE INTO EASTERN KENTUCKY BY 00Z SATURDAY...WHICH SHOULD PUT AN END TO THE SHOWERS ACROSS WESTERN PARTS OF THE FORECAST AREA. THIS REST OF THE AREA SHOULD SEE THE SHOWERS EXIT BY 06Z SATURDAY WITH COOLER AIR MOVING IN BEHIND THE FRONT. SPC SREF ENSEMBLES WERE SHOWING INCREASING MIXED LAYER CAPE TODAY WITH NEAR 500 J/KG NEAR MUNCIE AND AROUND 1000 J/K NEAR VINCENNES AT 21Z THIS AFTERNOON. THIS INSTABILITY SHOULD GRADUALLY WANE TONIGHT WITH NIGHTFALL AND FRIDAY WITH THE FRONT MOVING SOUTHEAST. DEEP MOISTURE AND STRONG FORCING WARRANT CATEGORICAL POPS TODAY THROUGH FRIDAY. AREA OF THUNDERSTORMS...CURRENTLY OVER SOUTHEASTERN MISSOURI AND NORTHEASTERN ARKANSAS AND ASSOCIATED WITH AN UPPER WAVE...SHOULD MOVE TO VINCENNES AND TERRE HAUTE AFTER 5 AM AND EAST OF THE AREA LATE MORNING PER THE 05Z HRRR RAPID REFRESH REFLECTIVITY PROGS. THUNDERSTORMS SHOULD MOVE BACK INTO THE AREA AND OTHERS POP UP THIS AFTERNOON AHEAD OF ANOTHER UPPER WAVE AND AGAIN TONIGHT WITH ANOTHER ONE. THUNDERSTORMS SHOULD BE CONFINED TO THE FAR SOUTHERN TIER OR TWO BY FRIDAY AS THE FRONT SETTLES SOUTHEAST AND STABILITY INCREASES NORTH OF THE FRONT. FINALLY...WILL ONLY CARRY EVENING SHOWER CHANCES ACROSS EAST CENTRAL INDIANA BY FRIDAY NIGHT. REGARDING SEVERE WEATHER POTENTIAL...THE 500-1000 J/KG CAPES COMBINED WITH AROUND 200 METERS SQUARED PER SECONDS SQUARED HELICITY...PER 21Z SPC SREF ENSEMBLES...SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED SEVERE WEATHER THIS AFTERNOON...ESPECIALLY SOUTHWEST OF INDIANAPOLIS...WHERE INSTABILITY SHOULD BE GREATER. SEVERE THREAT SHOULD END THIS EVENING...ESPECIALLY NORTH OF BLOOMINGTON...WITH LOSS OF SOLAR HEATING AND BETTER SHEAR SOUTH OF THERE. OVERALL...SPC DAY1 ENHANCED RISK ACROSS SOUTHERN PARTS OF KNOX...DAVIESS AND MARTIN COUNTIES AND SLIGHT RISK ELSEWHERE OVER CENTRAL INDIANA LOOKS GOOD WITH MAIN SEVERE THREATS BEING DAMAGING WINDS AND LARGE HAIL. HOWEVER...CAN NOT RULE OUT A TORNADO OR TWO AS LIFTED CONDENSATION LEVELS ARE FORECASTED TO LESS THAN 3000 FEET. IF EVEN BRIEF BREAKS OCCUR IN THE CLOUD COVER OCCUR...THIS COULD ALSO AID IN ROTATING STORMS. RAINFALL WILL BE ANOTHER ISSUE THROUGH FRIDAY AS JET STREAKS MOVE THROUGH THE 100 PLUS KNOT UPPER JET THAT WILL BE OVER THE AREA TONIGHT AND FRIDAY...PROVIDING STRONG UPPER DIVERGENCE. JET INTERACTIONS ALONG WITH DEEP MOISTURE...DISPLAYED BY PRECIPITABLE WATER VALUES TO NEAR 1.5 INCHES...OR TWICE OR MORE ABOVE NORMAL FOR EARLY APRIL...SUGGEST HEAVY RAIN MENTION TONIGHT WITH HEAVY RAIN ALSO POSSIBLE MAINLY SOUTH OF INTERSTATE 70 ON FRIDAY. FINALLY...SHOULD SEE BREEZY CONDITIONS TODAY WITH BUFKIT SUGGESTING GUSTS TO 30 MPH OR MORE ARE POSSIBLE THIS AFTERNOON...AFTER THE INVERSION DIES. WENT WITH DAYTIME TEMPERATURES AT OR BELOW 00Z MOS DO TO THICK CLOUD COVER. ALSO...WENT CLOSER TO THE MORE MILD 00Z NAM TEMPERATURES FOR OVERNIGHT LOWS...ESPECIALLY SOUTH OF THE FRONT. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... ISSUED AT 240 AM EST FRI APR 02 2015 FOCUS FOR THE SHORT TERM WILL BE ON TEMPERATURES AS MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA. MODEL RH TIME SECTIONS AND CU DEVELOPMENT PROGS SUGGEST THERE WILL BE LITTLE CLOUD COVER AROUND ON SATURDAY WITH PERHAPS SOME CIRRUS SPILLING OVER TOP OF A MISSISSIPPI RIDGE AND ACROSS CENTRAL INDIANA SATURDAY NIGHT. 850 MILLIBAR TEMPERATURE PROGS BRING IN SUB-ZERO TEMPERATURES SATURDAY MORNING BUT WARM IT UP TO 2 TO 4 DEGREES ABOVE ZERO SATURDAY NIGHT. HOWEVER...WITH SUNNY SKIES...SIMILAR 00Z MOS... SLIGHTLY BELOW NORMAL TEMPERATURES...LOOK OK WITH HIGHS IN THE 50S AND LOWS IN THE 30S. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... ISSUED AT 223 PM EDT THU APR 2 2015 MODELS ARE CLOSE ENOUGH THAT THE SUPERBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. CENTRAL INDIANA WILL REMAIN IN SOUTHWEST FLOW ALOFT THROUGH MUCH OF THE PERIOD...AND THIS WILL ALLOW A SURFACE FRONT TO MEANDER AROUND THE REGION DURING THE LONG TERM. CHANCES FOR RAIN AND TIMING OF RAIN WILL DEPEND ON EXACT FRONTAL LOCATION AND ANY UPPER IMPULSES IN THE SOUTHWEST FLOW...BOTH OF WHICH ARE TOO VARIABLE TO PIN DOWN THAT FAR OUT. WILL THUS STICK WITH SUPERBLEND AND ITS DAILY CHANCES FOR RAIN THROUGH THE PERIOD. TEMPERATURES WILL BOUNCE AROUND SOME DEPENDING ON WHERE THE SURFACE FRONT IS EACH DAY. && .AVIATION.../DISCUSSION FOR THE 021800Z TAF ISSUANCE/ ISSUED AT 1259 PM EDT THU APR 2 2015 VARIABLE CONDITIONS BECOMING PREDOMINANT MVFR. PERIODS OF CONVECTION ACROSS MOST SITES. CONFIDENCE MEDIUM TO LOW IN THE SPECIFICS. CONVECTION WILL BE OUT OF KLAF AND SHOULD BE NEAR OR OUT OF KHUF BY VALID TIME. AT THE OTHER TWO SITES WILL KEEP A TEMPO GROUP FOR A COUPLE OF HOURS TO COVER THIS FIRST AREA OF CONVECTION. MVFR EXPECTED. MUCH UNCERTAINTY IN REDEVELOPMENT OF CONVECTION LATER THIS AFTERNOON WITH COLD FRONT AND UPPER WAVE. WILL JUST GO WITH VC MENTION. MANY STATIONS UPSTREAM HAVE RETURNED TO VFR AND WILL ALLOW THIS TO HAPPEN AT MOST SITES FOR A PERIOD LATER THIS AFTERNOON. EXPECT MORE RAIN TO DEVELOP THIS EVENING AND OVERNIGHT ESPECIALLY ACROSS SOUTHERN SITES WHERE A COLD FRONT WILL STALL. MORE WIDESPREAD RAIN WILL ARRIVE FRIDAY AS AN AREA OF LOW PRESSURE MOVES IN. WITH THE UNCERTAINTY JUST WENT MVFR CEILINGS TONIGHT INTO FRIDAY...WITH THE EXCEPTION OF LAFAYETTE WHERE SLIGHTLY DRIER AIR SHOULD KEEP CEILINGS BETTER. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...MK/JH SHORT TERM...MK LONG TERM...50 AVIATION...50 VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
124 PM EDT THU APR 2 2015 .SYNOPSIS... ISSUED AT 400 AM EDT THU APR 2 2015 RAIN IS EXPECTED TO SPREAD ACROSS THE REGION TODAY AHEAD OF A COLD FRONT. THUNDERSTORMS WILL ALSO BE POSSIBLE AT TIMES. HIGH TEMPERATURES WILL GENERALLY BE IN THE 60S. RAIN WILL CONTINUE TONIGHT NEAR AND SOUTH OF THE FRONT AS IT SAGS INTO CENTRAL PORTIONS OF ILLINOIS...INDIANA AND OHIO. LOWS WILL RANGE FROM THE MIDDLE AND UPPER 30S NORTH TO THE UPPER 40S SOUTH. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 359 AM EDT THU APR 2 2015 UPSTREAM RADAR IS STILL PRETTY BENIGN...BUT HI RES GUIDANCE INCLUDING THE HRRR CONTINUE SHOW INCREASING COVERAGE OF SCATTERED SHOWERS AND TSTORMS BETWEEN NOW AND DAYBREAK ALONG THE LEADING EDGE OF 850MB MOISTURE ADVECTION ASSOCIATED WITH THE MID LEVEL WAVE CURRENTLY LOCATED NEAR SAINT LOUIS. THIS WAVE OF CONVECTION WILL BE OUT OF THE AREA BY MID DAY...BUT WILL QUICKLY BE REPLACED BY ADDITIONAL CONVECTION ASSOCIATED WITH THE OUTFLOW BOUNDARY/SYNOPTIC COLD FRONT MOVING OUT OF THE UPPER MIDWEST. LATEST SPC OUTLOOK HAS THE SOUTHERN HALF OF OUR FORECAST AREA IN A MARGINAL RISK FOR SEVERE WEATHER. THIS RISK SEEMS APPROPRIATE GIVEN THE CONDITIONAL THREAT. SURFACE DEWPOINTS WILL INCREASE INTO THE UPPER 50S BY MID DAY...BUT MEAGER MID-LEVEL LAPSE RATES...AND LIMITED SURFACE HEATING WILL LIMIT SEVERE POTENTIAL. CURRENT SATELLITE VIEW SHOWS THE CLOUDCOVER ASSOCIATED WITH THE MCS IN IOWA WILL BE RIGHT ON THE HEELS OF THE MID LEVEL WAVE MOVING THROUGH ILLINOIS...THUS PROVIDING LITTLE TIME FOR MUCH SOLAR INSOLATION. IF BREAKS IN THE CLOUDS DO OCCUR...A LOW END SEVERE WIND THREAT MAY MATERIALIZE GIVEN THE 35 TO 40 KNOTS OF DEEP LAYER SHEAR AND ~40 KNOTS OF FLOW ~2500 FEET OFF THE DECK. THURSDAY WILL BE WINDY WITH GUSTS TO 25 TO 30 MPH. IF AFOREMENTIONED BREAKS IN THE CLOUDS OCCUR...THIS WILL ALLOW FOR DEEPER MIXING AND STRONGER WIND GUSTS OF 35 TO 40 MPH. WINDS WILL DIE DOWN SIGNIFICANTLY BY THE EVENING HOURS ONCE THE COLD FRONT SLIDES THROUGH THE AREA. && .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 359 AM EDT THU APR 2 2015 SECONDARY WAVE WILL BE MOVING THROUGH THE REGION FRIDAY. MAIN FRONTAL BOUNDARY WILL BE TO OUR SOUTH BUT MOISTURE ADVECTION WILL SPREAD NORTH AND SHOULD SEE PCPN RE-DEVELOP ESPECIALLY OVER SOUTH AND SOUTHEAST DURING THE AFTERNOON. COUPLED UPPER LEVEL JET TO PROVIDE GOOD DIFFLUENCE ALOFT AND HAVE CONTINUED CATEGORICAL POPS SOUTH. THERMAL PROFILES STILL SUPPORT MAINLY RAIN ON FRIDAY. HOWEVER...TEMP PROFILES DO BEGIN TO HINT AT POSSIBLE WET SNOW MIX IF STRONG LIFT IS SUFFICIENT TO COOL LOWER LEVELS IN AFTERNOON. THIS TIMING IS NOT FAVORABLE GIVEN TIME OF YEAR AND WITH WARM BOUNDARY LAYER PREFER TO HOLD OFF ANY SNOW MENTION UNTIL EVENING HOURS WHEN COLDER AIR DEEPENS. AS PREVIOUSLY MENTIONED THIS WILL COINCIDE WITH DEEPER MOISTURE EXITING THE AREA SO NOT EXPECTING ANY ACCUMS AT THIS TIME. HIGH PRESSURE MOVES BACK IN FOR SATURDAY. WARM FRONT WILL BEGIN TO TAKE SHAPE OVER THE GREAT LAKES SATURDAY NIGHT INTO SUNDAY. THIS BOUNDARY TO BECOME PROBLEMATIC FOR REMAINDER OF FORECAST AS DEEPER SOUTHWEST FLOW DEVELOPS AND FRONT BECOMES QUASI STATIONARY OVER THE AREA AS TYPICAL FOR THIS TIME OF YEAR. OBVIOUS PROBLEMS SURROUND STRONG THERMAL CONTRAST ACROSS THIS BOUNDARY AND TEMP/POP FORECAST DEPENDENT ON ITS LOCATION. STAYED CLOSE TO PREVIOUS FORECAST FOR CONSISTENCY WITH FEW CHANGES TO THE LATER PERIODS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 118 PM EDT THU APR 2 2015 BAND OF SHRA/TS SHOULD MOVE EAST OF FWA BY 18Z. WIDESPREAD MVFR CIGS BEHIND THIS CONVECTION BACK TO THE CDFNT OVER NRN IL SHOULD PERSIST THIS AFTN WITH SCT SHRA/TS EXPECTED TO DVLP ALONG/AHEAD OF THE FRONT... HWVR GIVEN CLOUD COVER IN PLACE THERE IS SUFFICIENT UNCERTAINTY IN CONVECTIVE DEVELOPMENT TO LIMIT MENTION TO VCSH AT SBN AND VCTS AT FWA FOR NOW. WITH FROPA THIS EVE VFR CONDITIONS EXPECTED TO RETURN AFTER FROPA THIS EVE. LIGHT WINDS AND LINGERING LOW LEVEL MOISTURE OVERNIGHT AS FRONT STALLS TO THE S-SE MAY RESULT IN SOME MVFR VSBYS IN BR. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...LASHLEY SHORT TERM...BENTLEY LONG TERM...LASHLEY AVIATION...JT VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1259 PM EDT THU APR 2 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 240 AM EST THU APR 2 2015 UNSETTLED WEATHER EXPECTED THROUGH FRIDAY NIGHT AS A FRONTAL SYSTEM DROPS SOUTHEAST ACROSS THE OHIO VALLEY. THUNDERSTORMS WILL RETURN EARLY NEXT WEEK AS WELL WITH ANOTHER SYSTEM. THERE COULD BE A FEW SEVERE STORMS TODAY AND THIS EVENING AS WELL AS NEXT WEEK. HEAVY RAIN IS ALSO POSSIBLE AT TIMES THROUGH FRIDAY. MEANWHILE...HIGH PRESSURE WILL RESULT IN DRY BUT COOLER WEATHER SATURDAY AND SUNDAY. && .NEAR TERM /REST OF TODAY THROUGH FRIDAY NIGHT/... ISSUED AT 955 AM EDT THU APR 2 2015 UPDATE...DELAYED INCREASE OF SHOWERS AND THUNDERSTORMS A LITTLE THROUGH EARLY AFTERNOON BASED ON RADAR TRENDS AND RAPID REFRESH. ALSO DROPPED MENTION OF HEAVY RAINFALL UNTIL LATE AFTERNOON AND THEN ONLY MENTIONED IT OVER THE SOUTHERN 2/3 OF OUR REGION. TEMPERATURES AND THE REST OF THE NEAR TERM IS ON TRACK AND ONLY MINOR TWEAKS MADE TO GRIDS IN REST OF FORECAST. PREVIOUS NEAR TERM DISCUSSION FOLLOWS... MAIN FOCUS FOR THE NEAR TERM WILL BE THUNDERSTORMS TODAY THROUGH FRIDAY ALONG WITH POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND EVENING AND HEAVY RAIN THIS AFTERNOON THROUGH FRIDAY. DETERMINISTIC MODELS STILL HAVE TIMING DIFFERENCES REGARDING UPPER AND SURFACE WAVES AND CONSEQUENTLY TIMING OF THE COLD FRONT...THAT WAS OVER THE UPPER MIDWEST AND SOUTHERN PLAINS THIS OVERNIGHT. HOWEVER...THE DIFFERENCES IN THE 00Z RUN THIS EVENING...SAVE THE NAM...ARE NOT AS GREAT AS THEY ONCE WERE. THE 00Z GFS IS TRENDING FURTHER NORTH WITH ITS TRACK OF SURFACE WAVES AND THEREFORE FRONTAL POSITION ON FRIDAY PER THE STEADIER 12Z ECMWF. A FEW GEFS MEMBERS WERE CLOSE TO THE OPERATIONAL 12Z ECMWF AS WAS ECMWF ENSEMBLE MEAN. MEANWHILE...THE 00Z CANADIAN IS A BIT QUICKER WITH THE FRONT...ALBEIT SLOWER WITH THE UPSTREAM TROUGH. OVERALL...FEEL A BLEND OF THE 00Z GFS...12Z ECMWF AND 12Z ECENS LOOKS BEST. THE COLD FRONT SHOULD DROP SOUTHEAST TO NEAR MERRIVILLE AROUND 18Z THIS AFTERNOON...TO FAR NORTHERN PARTS OF CENTRAL INDIANA 00Z THIS EVENING...AND TO NEAR THE OHIO RIVER ON FRIDAY...BEFORE IT TEMPORARILY STALLS WITH THE WAVES MOVING ALONG IT. FINALLY...THE FRONT SHOULD MOVE INTO EASTERN KENTUCKY BY 00Z SATURDAY...WHICH SHOULD PUT AN END TO THE SHOWERS ACROSS WESTERN PARTS OF THE FORECAST AREA. THIS REST OF THE AREA SHOULD SEE THE SHOWERS EXIT BY 06Z SATURDAY WITH COOLER AIR MOVING IN BEHIND THE FRONT. SPC SREF ENSEMBLES WERE SHOWING INCREASING MIXED LAYER CAPE TODAY WITH NEAR 500 J/KG NEAR MUNCIE AND AROUND 1000 J/K NEAR VINCENNES AT 21Z THIS AFTERNOON. THIS INSTABILITY SHOULD GRADUALLY WANE TONIGHT WITH NIGHTFALL AND FRIDAY WITH THE FRONT MOVING SOUTHEAST. DEEP MOISTURE AND STRONG FORCING WARRANT CATEGORICAL POPS TODAY THROUGH FRIDAY. AREA OF THUNDERSTORMS...CURRENTLY OVER SOUTHEASTERN MISSOURI AND NORTHEASTERN ARKANSAS AND ASSOCIATED WITH AN UPPER WAVE...SHOULD MOVE TO VINCENNES AND TERRE HAUTE AFTER 5 AM AND EAST OF THE AREA LATE MORNING PER THE 05Z HRRR RAPID REFRESH REFLECTIVITY PROGS. THUNDERSTORMS SHOULD MOVE BACK INTO THE AREA AND OTHERS POP UP THIS AFTERNOON AHEAD OF ANOTHER UPPER WAVE AND AGAIN TONIGHT WITH ANOTHER ONE. THUNDERSTORMS SHOULD BE CONFINED TO THE FAR SOUTHERN TIER OR TWO BY FRIDAY AS THE FRONT SETTLES SOUTHEAST AND STABILITY INCREASES NORTH OF THE FRONT. FINALLY...WILL ONLY CARRY EVENING SHOWER CHANCES ACROSS EAST CENTRAL INDIANA BY FRIDAY NIGHT. REGARDING SEVERE WEATHER POTENTIAL...THE 500-1000 J/KG CAPES COMBINED WITH AROUND 200 METERS SQUARED PER SECONDS SQUARED HELICITY...PER 21Z SPC SREF ENSEMBLES...SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED SEVERE WEATHER THIS AFTERNOON...ESPECIALLY SOUTHWEST OF INDIANAPOLIS...WHERE INSTABILITY SHOULD BE GREATER. SEVERE THREAT SHOULD END THIS EVENING...ESPECIALLY NORTH OF BLOOMINGTON...WITH LOSS OF SOLAR HEATING AND BETTER SHEAR SOUTH OF THERE. OVERALL...SPC DAY1 ENHANCED RISK ACROSS SOUTHERN PARTS OF KNOX...DAVIESS AND MARTIN COUNTIES AND SLIGHT RISK ELSEWHERE OVER CENTRAL INDIANA LOOKS GOOD WITH MAIN SEVERE THREATS BEING DAMAGING WINDS AND LARGE HAIL. HOWEVER...CAN NOT RULE OUT A TORNADO OR TWO AS LIFTED CONDENSATION LEVELS ARE FORECASTED TO LESS THAN 3000 FEET. IF EVEN BRIEF BREAKS OCCUR IN THE CLOUD COVER OCCUR...THIS COULD ALSO AID IN ROTATING STORMS. RAINFALL WILL BE ANOTHER ISSUE THROUGH FRIDAY AS JET STREAKS MOVE THROUGH THE 100 PLUS KNOT UPPER JET THAT WILL BE OVER THE AREA TONIGHT AND FRIDAY...PROVIDING STRONG UPPER DIVERGENCE. JET INTERACTIONS ALONG WITH DEEP MOISTURE...DISPLAYED BY PRECIPITABLE WATER VALUES TO NEAR 1.5 INCHES...OR TWICE OR MORE ABOVE NORMAL FOR EARLY APRIL...SUGGEST HEAVY RAIN MENTION TONIGHT WITH HEAVY RAIN ALSO POSSIBLE MAINLY SOUTH OF INTERSTATE 70 ON FRIDAY. FINALLY...SHOULD SEE BREEZY CONDITIONS TODAY WITH BUFKIT SUGGESTING GUSTS TO 30 MPH OR MORE ARE POSSIBLE THIS AFTERNOON...AFTER THE INVERSION DIES. WENT WITH DAYTIME TEMPERATURES AT OR BELOW 00Z MOS DO TO THICK CLOUD COVER. ALSO...WENT CLOSER TO THE MORE MILD 00Z NAM TEMPERATURES FOR OVERNIGHT LOWS...ESPECIALLY SOUTH OF THE FRONT. && .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... ISSUED AT 240 AM EST FRI APR 02 2015 FOCUS FOR THE SHORT TERM WILL BE ON TEMPERATURES AS MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE OVER THE AREA. MODEL RH TIME SECTIONS AND CU DEVELOPMENT PROGS SUGGEST THERE WILL BE LITTLE CLOUD COVER AROUND ON SATURDAY WITH PERHAPS SOME CIRRUS SPILLING OVER TOP OF A MISSISSIPPI RIDGE AND ACROSS CENTRAL INDIANA SATURDAY NIGHT. 850 MILLIBAR TEMPERATURE PROGS BRING IN SUB-ZERO TEMPERATURES SATURDAY MORNING BUT WARM IT UP TO 2 TO 4 DEGREES ABOVE ZERO SATURDAY NIGHT. HOWEVER...WITH SUNNY SKIES...SIMILAR 00Z MOS... SLIGHTLY BELOW NORMAL TEMPERATURES...LOOK OK WITH HIGHS IN THE 50S AND LOWS IN THE 30S. && .LONG TERM /SUNDAY THROUGH THURSDAY/... ISSUED AT 320 AM EDT THU APR 2 2015 NUMEROUS OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE LONG TERM PERIOD AS BROAD LOW PRESSURE DEVELOPS TO THE WEST AND SLOWLY MOVES THROUGH THE REGION. THIS COULD POTENTIALLY EXACERBATE AN EXISTING HYDROLOGIC ISSUE DEPENDING ON HOW MUCH RAIN OCCURS IN THE NEXT 24 TO 48 HOURS. INSTABILITY INDICES SUGGEST THUNDER IS A POSSIBILITY IN NEARLY ALL PERIODS AND FORECAST WILL REFLECT THAT. && .AVIATION.../DISCUSSION FOR THE 021800Z TAF ISSUANCE/ ISSUED AT 1259 PM EDT THU APR 2 2015 VARIABLE CONDITIONS BECOMING PREDOMINANT MVFR. PERIODS OF CONVECTION ACROSS MOST SITES. CONFIDENCE MEDIUM TO LOW IN THE SPECIFICS. CONVECTION WILL BE OUT OF KLAF AND SHOULD BE NEAR OR OUT OF KHUF BY VALID TIME. AT THE OTHER TWO SITES WILL KEEP A TEMPO GROUP FOR A COUPLE OF HOURS TO COVER THIS FIRST AREA OF CONVECTION. MVFR EXPECTED. MUCH UNCERTAINTY IN REDEVELOPMENT OF CONVECTION LATER THIS AFTERNOON WITH COLD FRONT AND UPPER WAVE. WILL JUST GO WITH VC MENTION. MANY STATIONS UPSTREAM HAVE RETURNED TO VFR AND WILL ALLOW THIS TO HAPPEN AT MOST SITES FOR A PERIOD LATER THIS AFTERNOON. EXPECT MORE RAIN TO DEVELOP THIS EVENING AND OVERNIGHT ESPECIALLY ACROSS SOUTHERN SITES WHERE A COLD FRONT WILL STALL. MORE WIDESPREAD RAIN WILL ARRIVE FRIDAY AS AN AREA OF LOW PRESSURE MOVES IN. WITH THE UNCERTAINTY JUST WENT MVFR CEILINGS TONIGHT INTO FRIDAY...WITH THE EXCEPTION OF LAFAYETTE WHERE SLIGHTLY DRIER AIR SHOULD KEEP CEILINGS BETTER. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...MK NEAR TERM...MK/JH SHORT TERM...MK LONG TERM...NIELD AVIATION...50 VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1256 PM CDT THU APR 2 2015 .UPDATE... ISSUED AT 1018 AM CDT THU APR 2 2015 DOPPLER RADAR INDICATED THE RAIN HAS DIMINISHED RAPIDLY IN OUR FAR EASTERN COUNTIES WITH THE REMAINDER OF THE CWA DRY. HAVE UPDATED THE GRIDS TO REFLECT THIS TREND...REDUCING POPS TO SLIGHTS IN OUR FAR EASTERN CWA THE REMAINDER OF THE MORNING. LOW CLOUDS WILL BE PUSHING OFF TO OUR EAST FOLLOWED BY A PERIOD OF HIGH LEVEL CLOUDS BEFORE CLEARING THIS AFTERNOON FROM WEST TO EAST. BUREAU COUNTY RECEIVED THE MOST RAIN LAST NIGHT...AROUND ONE-HALF INCH. THE REMAINDER OF THE CWA REPORTED LESS THAN 1/4 INCH WITH SOME SPOTS NOT A DROP OF RAIN. UPDATE ISSUED AT 534 AM CDT THU APR 2 2015 UPDATE FOR MINOR CHANGES TO POPS AND RAINFALL AMOUNTS. ALSO SCALED THUNDER MENTION BACK TO ISOLATED. RAIN COVERAGE HAS INCREASED SOMEWHAT OVER THE PAST COUPLE OF HOURS. INTENSITY HAS PICKED UP ACROSS THE SOUTH WITH INCREASED FORCING FROM APPROACHING SHORTWAVE...WHILE THE STORMS IN THE FAR EAST LOOK TO BE FUELED BY THE NOSE OF A NEAR 50 KT LOW LEVEL JET. RAIN STILL ON TRACK TO MOVE EAST OF THE FORECAST AREA AROUND MIDDAY. && .SYNOPSIS... ISSUED AT 232 AM CDT THU APR 2 2015 AT 300 AM CDT...A COLD FRONT HAD PUSHED INTO CENTRAL IOWA. MORE FAVORABLE MOISTURE AHEAD OF THE BOUNDARY HAD FINALLY MADE IT INTO EASTERN IOWA...WITH DEWPOINTS IN THE LOW/MID 50S. SHOWERS/SCATTERED THUNDERSTORMS ALONG AND EAST OF THE FRONT WERE MOVING INTO THE FAR WESTERN FRINGE OF THE FORECAST AREA...FUELED BY A RIBBON OF MU CAPE AOA 500 J/KG AND A SWATH OF STEEPER MID LEVEL LAPSE RATE. A SHORT WAVE TROUGH LIFTING THROUGH ILLINOIS IS SUPPORTING ISOLATED CONVECTION ACROSS THE FAR EASTERN COUNTIES. EARLY MORNING TEMPERATURES WERE IN THE 50S TO LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 232 AM CDT THU APR 2 2015 THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD IS PRECIP TRENDS/COVERAGE/AMOUNTS THROUGH EARLY AFTERNOON. IN THE NEAR TERM...HIGH RESOLUTION MODELS INCLUDING THE HRRR AND ARW/NMM ARE RUNNING A BIT SLOW BUT OTHERWISE HAVE THE CURRENT WEATHER MODELED WELL. HAVE ADJUSTED POPS FOR NEAR TERM TRENDS. HIGHEST QPF THROUGH 12Z WILL BE FOCUSED ACROSS THE WEST AND THE FAR EASTERN FRINGE...WITH SPOTTIER RAIN COVERAGE CENTRAL. AFTER 12Z...HIGHEST QPF AND SHOWER/STORM COVERAGE SHOULD BE LOCATED ALONG/EAST OF THE MISSISSIPPI RIVER AS THE UPSTREAM SHORTWAVE INTERACTS WITH THE COLD FRONT. TOTAL QPF NOW LOOKS LIKE IT WILL FALL MAINLY IN THE TENTH TO THIRD OF AN INCH RANGE. THE CHANCE OF ANY SEVERE WEATHER IS VIRTUALLY NIL. RAIN WILL END IN THE SOUTHEAST/EAST DURING THE EARLY AFTERNOON. BLENDED TEMPERATURE GUIDANCE IN THE MID/UPPER 60S FOR AFTERNOON HIGHS LOOKS REASONABLE. FOR TONIGHT...SOME LIGHT RAIN MAY SPREAD INTO THE WEST LATE...AHEAD OF ANOTHER WEAK SHORTWAVE TROUGH. EXPECT LOWS IN THE UPPER 30S/MID 40S. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 232 AM CDT THU APR 2 2015 AN ACTIVE WEATHER PATTERN FOR THE LONG TERM IS THE MAIN FORECAST CONCERN. THE BEGINNING OF THE PERIOD SEES ONE SYSTEM WITH NUMEROUS FORECAST ISSUES MOVING OUT OF THE AREA...FOLLOWED BY A FEW QUICK SYSTEMS...THEN AN ACTIVE WEEK NEXT WEEK WITH NUMEROUS SYSTEMS AND CHANCES FOR RAIN. LIKE ADVERTISED LAST NIGHT IN THE AFD...A COLD FRONT STALLS OUT TO OUR SOUTH AS THE MAIN FORCING MOVES QUICKLY TO THE EAST. AT THE SAME TIME ANOTHER WAVE IS MOVING ACROSS THE CENTRAL UNITED STATES. THIS WAVE INTERACTS WITH THE SURFACE FRONT...BRINGING IT SLIGHTLY NORTH AND THEN INDUCING SURFACE CYCLOGENESIS AND MOVING THE FRONT OUT OF THE AREA. THE GEM AND THE GFS ARE THE TWO MODELS WITH THE MOST PRECIP NORTH INTO OUR AREA. WHILE TEMPERATURES WILL BE WELL ABOVE FREEZING...THE SREF MEAN SUGGESTS THAT THE TEMPS IN EARLY AFTERNOON WILL BE CONDUCIVE TO SNOWFALL. THE REST OF THE DETERMINISTIC MODELS HAVE US ABOVE FREEZING. THE OPERATIONAL NAM...A MEMBER OF THE SREF...HAS NO QPF FOR US DURING THIS TIME. SO THERE IS A LARGE SPREAD IN THE MEMBERS IN THE SREF. THINK THE SREF MEAN IS BEING SWAYED HEAVILY BY ONE MEMBER...SO DONT THINK WE WILL SEE SNOW. FRIDAY EVENING THROUGH SUNDAY AFTERNOON LOOKS TO BE DRY FOR OUR AREA. ANOTHER CLIPPER MOVES THROUGH WISCONSIN. LATEST RUNS BRING THE QPF WITH THIS SYSTEM FURTHER NORTH...SO ONLY OUR FAR NORTHERN ZONES HAVE A SLIGHT CHANCE FOR POPS. WITH THE THERMAL PROFILE IT APPEARS THAT RASN MIX WOULD BE PREFERRED FOR ANY PRECIP THAT FALLS. MONDAY THROUGH TUESDAY EVENING...AN ACTIVE PATTERN SETS UP OVER THE AREA AND IT LOOKS LIKE WE SEE QPF THROUGH THE PERIOD. MODELS ARE IN AGREEMENT IN THE OVERALL LARGE SCALE PATTERN...HOWEVER THE FINESCALE FEATURES ARE YET TO BE AGREED UPON. IT LOOKS LIKE THE BEST CHANCE FOR THUNDER AT THIS TIME WILL BE MONDAY AFTERNOON THROUGH THE NIGHT. WEDNESDAY AND THURSDAY...THE MODELS HAVE FLIP FLOPPED ON LARGE SCALE FEATURES AND ARE DIFFERENT IN SOLUTIONS WITH THE ECMWF BEING WET AND THE GFS BEING DRY. OBVIOUSLY AS WE GET CLOSER THIS WILL BE THE NEXT FORECAST CONCERN BY EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1255 PM CDT THU APR 2 2015 VFR CONDS THROUGH THIS TAF CYCLE. LOW PRESSURE TRACKING ACROSS THE MID MS VALLEY ON FRIDAY WILL SPREAD A LIGHT RAIN SHIELD AS FAR NORTH AS ABOUT HIGHWAY 30. ON THE NORTH FRINGE THERE MAY BE A RAIN/SNOW MIX AT KCID/KMLI. NORTHWEST WINDS 10 TO 20 KNOTS THIS AFTERNOON THEN LESS THAN 10 KNOTS TONIGHT. NORTH WINDS 10 TO 20 KNOTS ON FRIDAY. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...HAASE SYNOPSIS...RP KINNEY SHORT TERM...RP KINNEY LONG TERM...GIBBS AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
400 PM MDT THU APR 2 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 209 PM MDT THU APR 2 2015 SHORT WAVE TROUGH WILL MOVE ACROSS NORTHEAST COLORADO 00Z-06Z...AND ACROSS SOUTHWEST NEBRASKA AND NORTHWEST KANSAS 06Z-12Z. CHALLENGES WITH THIS FORECAST ARE THE QPFS PLUS THE LOCATION/TIMING OF THE PHASE CHANGE. FROM 00Z TO 06Z...CLEARING OVER SOUTHEAST COLORADO HAS ALLOWED DECENT SURFACE HEATING AND PRODUCED MOST UNSTABLE CAPES AROUND 250 J/KG. HRRR MODEL SWEEPS THIS INSTABILITY ACROSS THE FORECAST AREA THROUGH THE EVENING. COMBINE THIS WITH SYNOPTIC ASCENT ASSOCIATED WITH DIFFERENTIAL CYCLONIC VORTICITY ADVECTION...AND THERE WILL BE A CHANCE OF ELEVATED THUNDERSTORMS THIS EVENING. HRRR DEVELOPS CONVECTION AROUND GOODLAND ABOUT 01Z NEAR A SURFACE CONVERGENCE ZONE...AND ADVECTS CONVECTION EAST THROUGH 03Z. LOW LEVELS WILL BE SOMEWHAT COOL/STABLE...SO DO NOT EXPECT SEVERE WEATHER WITH THIS CONVECTION. FROM 06Z TO 12Z...COLD FRONT WILL PUSH THROUGH THE FORECAST AREA...AND SHOULD BE MOSTLY SOUTH OF THE AREA BY 06Z. MODELS HAVE BEEN FAIRLY CONSISTENT WITH ADVECTING MOISTURE OVER THE AREA. MODEL CONSENSUS QPFS RANGE FROM A TENTH OF AN INCH ACROSS CHEYENNE COUNTY COLORADO TO AROUND ONE HALF INCH ACROSS RED WILLOW COUNTY NEBRASKA. MODEL SOUNDINGS INDICATE THE PHASE CHANGE TO SNOW WILL OCCUR ACROSS EASTERN COLORADO AROUND 04Z...FAR WESTERN KANSAS AROUND 08Z...AND THE FAR EASTERN PART OF THE AREA AROUND 12Z. SNOW AMOUNTS...OF COURSE...WILL DEPENDENT ON WHEN THE PHASE CHANGE OCCURS. WILL GO WITH 1-2 INCHES OF SNOW ACROSS YUMA COUNTY WHERE SNOW DURATIONS WILL BE THE LONGEST...TO LESS THAN 1/2 INCH FURTHER EAST. SHORT WAVE TROUGH WILL EJECT RAPIDLY EAST FRIDAY. AFTER SOME LINGERING PRECIPITATION EARLY IN THE MORNING...AIR MASS WILL DRY. TEMPERATURES WILL REMAIN COOL...IN THE 50S. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 209 PM MDT THU APR 2 2015 GOING INTO THE EXTENDED PERIOD AND THE START OF THE UPCOMING WEEKEND...UP TO A 72-HOUR PERIOD OF ABOVE NORMAL TEMPERATURES AND VERY DRY CONDITIONS WILL ENSUE FOR THE FORECAST AREA. THROUGH NEXT MONDAY...WEAK RIDGING AT BOTH 700/500 MB WILL GIVE WAY TO ZONAL FLOW FROM THE WSW WHILE SURFACE FLOW DURING THIS TIME WILL BE MORE SSW AS HIGH PRESSURE SETS UP OFF TO OUR EAST...WITH LEE-SIDE TROUGH ALSO SETTING UP LATE IN THE WEEKEND OVER THE FRONT RANGE AND EVENTUALLY MOVING OVER THE CWA AT THE BEGINNING OF NEXT WEEK. THIS WILL AID IN THE WAA/LOW RH DRAW FROM MEXICO. 850 MB TEMPS START OFF THE WEEKEND IN THE +13C TO +19C ON SATURDAY FROM LATEST GFS/ECMWF...WITH WARMEST AREAS WEST AND SOUTH. TEMPS INCREASE INTO THE +18C TO +24C RANGE GOING INTO SUNDAY WITH AGAIN WARMEST AREAS WEST AS WEAK RIDGING CONTINUES INTO THE PLAINS REGION. THIS IS GOING TO BE FOLLOWED BY 850 TEMPS DIFFERING BETWEEN THE LATEST RUNS OF THE GFS/ECMWF AS TIMING WITH SURFACE BOUNDARY FROM THE NORTH AT ISSUE. GFS(+19C TO +25C...WARMEST SOUTH) AND ECMWF(+10C TO +17C...WARMEST SOUTH). THE LATTER COULD MEAN EARLY/SLIGHTLY LOWER HIGHS WITH ARRIVAL OF LOW LEVEL COOLER AIRMASS. THESE NUMBERS WILL GIVE THE CWA HIGH TEMPERATURES WELL INTO THE 70S...WITH OVERNIGHT LOWS INCREASING FROM THE 30S TO LOW 40S. WITH THE STRONG WAA INTO THE REGION FOR THIS TIMEFRAME COMES THE LOW RELATIVE HUMIDITY READINGS IN TANDEM INCREASING HIGHS. BOUNDARY LAYER/SURFACE RH FROM LATEST GFS/ECMWF DO SHOW THE AREA OF 15 PERCENT OR LOWER STARTING IN EASTERN COLORADO...EXPANDING TO MOSTLY WESTERN ZONES SUNDAY...THEN ENTIRE CWA FOR MONDAY AHEAD OF BOUNDARY...BUT LATEST ECMWF DOES SHOW INCREASING RH OVER NORTHERN ZONES DUE TO BOUNDARY ARRIVING A BIT EARLIER THAN GFS. THE COMBINATION OF THE SSW SFC FLOW AND DOWNSLOPE MID LEVEL WINDS AT 700/500 MB COULD BRING THE FIRE WX DANGER CHANCES UP DURING THIS TIME. AT THIS TIME LATEST BUFKIT SHOWS WINDS POTENTIALLY MIXING DOWN IN THE 30-40KT RANGE SO WILL HAVE TO BE MONITORED...MAINLY FOR THE AFTERNOON HOUR PERIODS. FOR THE LATTER PORTION OF THE EXTENDED...MONDAY NIGHT THROUGH THURSDAY...THE ENTIRE FORECAST AREA WILL BEGIN TO SEE A LOWERING/DROP OFF IN TEMPS FROM THE ABOVE NORMAL CONDITIONS SEEN OVER THE WEEKEND. IN FOCUS FOR THIS TO OCCUR WILL BE A SHIFTING OF THE REMAINING MID LEVEL RIDGE TO OUR EAST AND A DEEPENING TROUGH THAT STARTS OFF OVER THE PACIFIC NW TUESDAY...THEN INTO THE CENTRAL ROCKIES WEDNESDAY...FOLLOWED BY A SHIFT EASTWARD INTO THE PLAINS REGION ON THURSDAY. AS THE SYSTEM ARRIVES IN THE CENTRAL ROCKIES...A WEAK SHORTWAVE WILL PUSH OFF THE BASE OF THE TROUGH GIVING THE SLIGHT CHANCE FOR LIGHT PRECIP TO NORTHERN ZONES. LARGE SURFACE RIDGE NOSING SOUTH UNDER THE SHORTWAVE WILL LIMIT ANY MAJOR CHANCES FOR PRECIP UNTIL THURSDAY WHEN SYSTEM SHIFTS EAST OFF THE ROCKIES...TAPPING INTO ESE SURFACE FLOW ALLOWING FOR MORE MOISTURE/INSTABILITY TO SUPPORT HIGHER CHANCE FOR SHOWERS. SPOTS IN EASTERN COLORADO WILL HIT A BRIEF PERIOD TOWARDS 12Z THURSDAY FOR TEMPS TO GIVE SOME LIGHT SNOW SHOWERS...OTHERWISE TEMPS WARM ENOUGH TO SUPPORT -RW THRU EVENT. MODEL QPF SUPPORTS 0.05-0.10" OVER A 48- HOUR PERIOD. TEMPS MONDAY NIGHT THRU THURSDAY WILL HAVE HIGHS IN THE MID 50S THRU THE MID 60S...COOLEST WEDNESDAY DUE TO CLOUDS FROM SHORTWAVE MOVEMENT. OVERNIGHT LOWS WILL RANGE MAINLY IN THE MID 30S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 400 PM MDT THU APR 2 2015 KGLD...VFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH 02Z WITH GUSTY NORTHEAST WINDS AND POSSIBLY A THUNDERSTORM AROUND 01Z. FROM 02Z-10Z IFR/VLIFR CIGS EXPECTED ALONG WITH NORTH WINDS GUSTING 25-30KTS BEHIND A COLD FRONTS PASSAGE. LIGHT RAIN/RAIN EXPECTED WITH SOME REDUCED VISIBILITIES BUT THE GREATER IMPACT TO AVIATION WILL BE THE CIGS. SOME LIGHT SNOW IS POSSIBLE AROUND 09Z FOR AN HOUR OR SO. AROUND 11Z CIGS IMPROVE TO MVFR WITH NORTH WINDS 10KTS OR SO. BY 16Z AND THROUGH THE REST OF THE TAF PERIOD AM EXPECTING VFR CONDITIONS WITH A SLOW DECREASE IN CLOUDINESS AND NORTHWEST WINDS NEAR 12KTS. UPDATES TO THE TAF ARE LIKELY DURING THE EVENING HOURS. KMCK...VFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH 01Z OR SO WITH NORTHEAST WINDS GUSTING TOWARD 20KTS. FROM 01Z-14Z IFR CIGS EXPECTED ALONG WITH NORTHEAST WINDS GUSTING TO 25KTS AND SOME LIGHT RAIN. SOME LIGHT SNOW IS POSSIBLE FROM 11Z-14Z. AROUND 15Z-21Z CIGS IMPROVE TO VFR WITH NORTHWEST WINDS GUSTING 20KTS. AFTER 22Z JUST A FEW CUMULUS CLOUDS AND NORTHWEST WINDS AROUND 10KTS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...MENTZER LONG TERM...JN AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
209 PM MDT THU APR 2 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 209 PM MDT THU APR 2 2015 SHORT WAVE TROUGH WILL MOVE ACROSS NORTHEAST COLORADO 00Z-06Z...AND ACROSS SOUTHWEST NEBRASKA AND NORTHWEST KANSAS 06Z-12Z. CHALLENGES WITH THIS FORECAST ARE THE QPFS PLUS THE LOCATION/TIMING OF THE PHASE CHANGE. FROM 00Z TO 06Z...CLEARING OVER SOUTHEAST COLORADO HAS ALLOWED DECENT SURFACE HEATING AND PRODUCED MOST UNSTABLE CAPES AROUND 250 J/KG. HRRR MODEL SWEEPS THIS INSTABILITY ACROSS THE FORECAST AREA THROUGH THE EVENING. COMBINE THIS WITH SYNOPTIC ASCENT ASSOCIATED WITH DIFFERENTIAL CYCLONIC VORTICITY ADVECTION...AND THERE WILL BE A CHANCE OF ELEVATED THUNDERSTORMS THIS EVENING. HRRR DEVELOPS CONVECTION AROUND GOODLAND ABOUT 01Z NEAR A SURFACE CONVERGENCE ZONE...AND ADVECTS CONVECTION EAST THROUGH 03Z. LOW LEVELS WILL BE SOMEWHAT COOL/STABLE...SO DO NOT EXPECT SEVERE WEATHER WITH THIS CONVECTION. FROM 06Z TO 12Z...COLD FRONT WILL PUSH THROUGH THE FORECAST AREA...AND SHOULD BE MOSTLY SOUTH OF THE AREA BY 06Z. MODELS HAVE BEEN FAIRLY CONSISTENT WITH ADVECTING MOISTURE OVER THE AREA. MODEL CONSENSUS QPFS RANGE FROM A TENTH OF AN INCH ACROSS CHEYENNE COUNTY COLORADO TO AROUND ONE HALF INCH ACROSS RED WILLOW COUNTY NEBRASKA. MODEL SOUNDINGS INDICATE THE PHASE CHANGE TO SNOW WILL OCCUR ACROSS EASTERN COLORADO AROUND 04Z...FAR WESTERN KANSAS AROUND 08Z...AND THE FAR EASTERN PART OF THE AREA AROUND 12Z. SNOW AMOUNTS...OF COURSE...WILL DEPENDENT ON WHEN THE PHASE CHANGE OCCURS. WILL GO WITH 1-2 INCHES OF SNOW ACROSS YUMA COUNTY WHERE SNOW DURATIONS WILL BE THE LONGEST...TO LESS THAN 1/2 INCH FURTHER EAST. SHORT WAVE TROUGH WILL EJECT RAPIDLY EAST FRIDAY. AFTER SOME LINGERING PRECIPITATION EARLY IN THE MORNING...AIR MASS WILL DRY. TEMPERATURES WILL REMAIN COOL...IN THE 50S. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 209 PM MDT THU APR 2 2015 GOING INTO THE EXTENDED PERIOD AND THE START OF THE UPCOMING WEEKEND...UP TO A 72-HOUR PERIOD OF ABOVE NORMAL TEMPERATURES AND VERY DRY CONDITIONS WILL ENSUE FOR THE FORECAST AREA. THROUGH NEXT MONDAY...WEAK RIDGING AT BOTH 700/500 MB WILL GIVE WAY TO ZONAL FLOW FROM THE WSW WHILE SURFACE FLOW DURING THIS TIME WILL BE MORE SSW AS HIGH PRESSURE SETS UP OFF TO OUR EAST...WITH LEE-SIDE TROUGH ALSO SETTING UP LATE IN THE WEEKEND OVER THE FRONT RANGE AND EVENTUALLY MOVING OVER THE CWA AT THE BEGINNING OF NEXT WEEK. THIS WILL AID IN THE WAA/LOW RH DRAW FROM MEXICO. 850 MB TEMPS START OFF THE WEEKEND IN THE +13C TO +19C ON SATURDAY FROM LATEST GFS/ECMWF...WITH WARMEST AREAS WEST AND SOUTH. TEMPS INCREASE INTO THE +18C TO +24C RANGE GOING INTO SUNDAY WITH AGAIN WARMEST AREAS WEST AS WEAK RIDGING CONTINUES INTO THE PLAINS REGION. THIS IS GOING TO BE FOLLOWED BY 850 TEMPS DIFFERING BETWEEN THE LATEST RUNS OF THE GFS/ECMWF AS TIMING WITH SURFACE BOUNDARY FROM THE NORTH AT ISSUE. GFS(+19C TO +25C...WARMEST SOUTH) AND ECMWF(+10C TO +17C...WARMEST SOUTH). THE LATTER COULD MEAN EARLY/SLIGHTLY LOWER HIGHS WITH ARRIVAL OF LOW LEVEL COOLER AIRMASS. THESE NUMBERS WILL GIVE THE CWA HIGH TEMPERATURES WELL INTO THE 70S...WITH OVERNIGHT LOWS INCREASING FROM THE 30S TO LOW 40S. WITH THE STRONG WAA INTO THE REGION FOR THIS TIMEFRAME COMES THE LOW RELATIVE HUMIDITY READINGS IN TANDEM INCREASING HIGHS. BOUNDARY LAYER/SURFACE RH FROM LATEST GFS/ECMWF DO SHOW THE AREA OF 15 PERCENT OR LOWER STARTING IN EASTERN COLORADO...EXPANDING TO MOSTLY WESTERN ZONES SUNDAY...THEN ENTIRE CWA FOR MONDAY AHEAD OF BOUNDARY...BUT LATEST ECMWF DOES SHOW INCREASING RH OVER NORTHERN ZONES DUE TO BOUNDARY ARRIVING A BIT EARLIER THAN GFS. THE COMBINATION OF THE SSW SFC FLOW AND DOWNSLOPE MID LEVEL WINDS AT 700/500 MB COULD BRING THE FIRE WX DANGER CHANCES UP DURING THIS TIME. AT THIS TIME LATEST BUFKIT SHOWS WINDS POTENTIALLY MIXING DOWN IN THE 30-40KT RANGE SO WILL HAVE TO BE MONITORED...MAINLY FOR THE AFTERNOON HOUR PERIODS. FOR THE LATTER PORTION OF THE EXTENDED...MONDAY NIGHT THROUGH THURSDAY...THE ENTIRE FORECAST AREA WILL BEGIN TO SEE A LOWERING/DROP OFF IN TEMPS FROM THE ABOVE NORMAL CONDITIONS SEEN OVER THE WEEKEND. IN FOCUS FOR THIS TO OCCUR WILL BE A SHIFTING OF THE REMAINING MID LEVEL RIDGE TO OUR EAST AND A DEEPENING TROUGH THAT STARTS OFF OVER THE PACIFIC NW TUESDAY...THEN INTO THE CENTRAL ROCKIES WEDNESDAY...FOLLOWED BY A SHIFT EASTWARD INTO THE PLAINS REGION ON THURSDAY. AS THE SYSTEM ARRIVES IN THE CENTRAL ROCKIES...A WEAK SHORTWAVE WILL PUSH OFF THE BASE OF THE TROUGH GIVING THE SLIGHT CHANCE FOR LIGHT PRECIP TO NORTHERN ZONES. LARGE SURFACE RIDGE NOSING SOUTH UNDER THE SHORTWAVE WILL LIMIT ANY MAJOR CHANCES FOR PRECIP UNTIL THURSDAY WHEN SYSTEM SHIFTS EAST OFF THE ROCKIES...TAPPING INTO ESE SURFACE FLOW ALLOWING FOR MORE MOISTURE/INSTABILITY TO SUPPORT HIGHER CHANCE FOR SHOWERS. SPOTS IN EASTERN COLORADO WILL HIT A BRIEF PERIOD TOWARDS 12Z THURSDAY FOR TEMPS TO GIVE SOME LIGHT SNOW SHOWERS...OTHERWISE TEMPS WARM ENOUGH TO SUPPORT -RW THRU EVENT. MODEL QPF SUPPORTS 0.05-0.10" OVER A 48- HOUR PERIOD. TEMPS MONDAY NIGHT THRU THURSDAY WILL HAVE HIGHS IN THE MID 50S THRU THE MID 60S...COOLEST WEDNESDAY DUE TO CLOUDS FROM SHORTWAVE MOVEMENT. OVERNIGHT LOWS WILL RANGE MAINLY IN THE MID 30S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1120 AM MDT THU APR 2 2015 PRECIPITATION CHANCES AND ASSOCIATED MVFR CONDITIONS WILL INCREASE AFTER 00Z AT BOTH KGLD AND KMCK. FROM 18Z-00Z VFR CEILINGS WILL OCCUR AT BOTH SITES. ALTHOUGH INSTABILITY IS LACKING...EXPECT ENOUGH LIFT FROM APPROACHING SHORTWAVE TROUGH TO PRODUCE SHOWERS AND A FEW THUNDERSTORMS AFTER 22Z...AND MENTIONED STORMS IN THE VICINITY OF BOTH SITES. MAIN MOISTURE WILL MOVE OVER THE AREA AFTER 06Z...AND TEMPERATURES BEHIND A COLD FRONT WILL DROP STEADILY AFTER THAT TIME. SO...EXPECT RAIN TURNING TO SNOW FROM 08Z-12Z. SNOW ACCUMULATIONS WILL BE LIGHT...BUT CEILINGS/VISIBILITIES WILL BE IN THE MVFR CATEGORY...AND POSSIBLY LOWER. SURFACE WINDS BEHIND THE COLD FRONT WILL BE NORTHEAST AT 15-25 KNOTS WITH A FEW HIGHER GUSTS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...MENTZER LONG TERM...JN AVIATION...MENTZER
AREA FORECAST DISCUSSION
NWS JACKSON KY
152 PM EDT THU APR 2 2015 .UPDATE... ISSUED AT 152 PM EDT THU APR 2 2015 UPDATED SHORT TERM GRIDS BASED ON LATEST OBSERVATIONAL TRENDS. HAVE ISSUED FLASH FLOOD WATCH EFFECTIVE TONIGHT AT 8PM THROUGH 11 PM FRIDAY. FOLLOWED LATEST WPC EXCESSIVE RAINFALL GUIDANCE AND 12Z MODEL RUNS...AND COORDINATED WITH NESDIS AND NEIGHBORING WFOS. GREATEST THREAT IS THE NORTHERN PART OF THE WATCH...BUT WANTED TO ALLOW A BUFFER ON THE SOUTHEAST SIDE OF THE WATCH SO HAVE INCLUDED ALL BY THE VA BORDER COUNTIES. UPDATE ISSUED AT 1013 AM EDT THU APR 2 2015 HAVE UPDATED NDFD AND ASSOCIATED PRODUCTS BASED ON LATEST RADAR...SATELLITE AND OBSERVATIONAL TRENDS. BASED ON TRENDS AND SUPPORT FROM THE LATEST HRRR HAVE LOW RAIN CHANCES NEXT FEW HOURS WITH INCREASING TREND INTO THE AFTERNOON. WILL BE EXAMINING THE FLASH FLOOD THREAT FOR TONIGHT INTO FRIDAY...AND MAKE DETERMINATION ON A FLASH FLOOD WATCH EARLY THIS AFTERNOON. THE WPC DAY 1 EXCESSIVE RAINFALL OUTLOOK HAS BEEN UPDATED TO INCLUDE THE ENTIRE FORECAST AREA FOR THE PERIOD THROUGH 12Z FRIDAY. UPDATE ISSUED AT 816 AM EDT THU APR 2 2015 SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER OUR WESTERN COUNTIES EARLY THIS MORNING. OUR FAR NW COUNTIES SHOULD BE IMPACTED THE MOST. HAVE MADE MINOR ADJUSTMENTS FOR OBSERVED CONDITIONS. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 400 AM EDT THU APR 2 2015 DESPITE VERY DRY AIR LINGERING ALOFT OVER THE REGION...A WET AND STORMY PERIOD IS IN STORE. AT 3 AM RIDGETOPS STILL HAD DEW POINTS IN THE TEENS AND RELATIVE HUMIDITY IN THE 20S. HOWEVER...GULF OF MEXICO MOISTURE WAS ON THE WAY IN. SURFACE DEW POINTS WERE NEAR 60 FROM NORTHERN ALABAMA TO WESTERN KENTUCKY...WITH THUNDERSTORMS ONGOING OVER WESTERN KENTUCKY. THIS MOISTURE WILL QUICKLY ADVECTED INTO OUR AREA TODAY. AS THE SHORTWAVE TROUGH CAUSING CONVECTION IN WESTERN KENTUCKY MOVES EAST TODAY...PRECIP WILL DEVELOP. IT WILL INITIALLY BATTLE LOW LEVEL DOWNSLOPE FLOW AND DRY AIR OVER OUR AREA...AND ONLY CHANCE CATEGORY POPS HAVE BEEN USED TODAY FOR MOST LOCATIONS. OUR FAR NW COUNTIES WILL HAVE THE BEST UPPER LEVEL SUPPORT AND WILL BE OUTSIDE OF THE DOWNSLOPE INFLUENCE...AND LIKELY POPS HAVE BEEN PLACED THERE. LOW LEVEL FLOW WILL BECOME MORE SOUTHWESTERLY TONIGHT AND DOWNSLOPE INFLUENCE WILL BE LOST. A COLD FRONT WILL APPROACH FROM THE NORTHWEST AND PROVIDE A FOCUS FOR MORE PRECIP. THE HIGHEST POPS WILL BE IN OUR NORTHWEST COUNTIES...BUT ALL AREAS WILL HAVE A HIGHER POP. HOWEVER...THE BEST SUPPORT FOR PRECIP WILL BE IN OUR NORTHERN COUNTIES AS A COLD FRONT APPROACHES FROM THE NORTHWEST. THE FRONT WILL STALL NEAR THE OHIO RIVER ON FRIDAY...AND THEN GET A PUSH SOUTHEAST THROUGH THE JKL FORECAST AREA ON FRIDAY NIGHT AS AN UPPER TROUGH PROMPTS A LOW PRESSURE WAVE TO TRAVEL ALONG THE FRONT. AT THIS POINT...THE AXIS OF HEAVIEST PRECIP LOOKS LIKE IT WILL BE JUST TO OUR NORTH DUE TO THE POSITION OF THE STALLED FRONT. THIS WILL NEED TO BE WATCHED...SINCE A SLIGHT SOUTHWARD SHIFT WOULD MEAN HEAVIER PRECIP FOR OUR NORTHERN COUNTIES AND A GREATER THREAT OF FLOODING. FOR THE TIME BEING...HAVE HELD OFF ON A FLOOD WATCH. PLENTY OF SHEAR WILL BE AVAILABLE TO SUPPORT ORGANIZED CONVECTION DURING THIS EVENT...AND SEVERE STORMS CAN NOT BE RULED OUT. HOWEVER...THE GREATEST INSTABILITY IS EXPECTED TO BE TO OUR WEST AND SOUTHWEST IN THE AREA OF HIGHER LOW-LEVEL THETA E...AND THE GREATEST RISK OF SEVERE WEATHER SHOULD BE THERE. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 400 AM EDT THU APR 2 2015 THE LONG TERM PERIOD STARTS AS ANY REMAINING CONVECTION...RAIN...AND COLD FRONT PUSH THROUGH OUR AREA. THE MODELS ARE IN GOOD AGREEMENT WITH THE TIMING OF THE FRONTAL PASSAGE WHICH IS BETWEEN 00Z AND 06Z SATURDAY FOR THE EASTERN MOST PORTION OF KENTUCKY. COOLER...DRIER AIR WILL THEN QUICKLY MOVE IN DURING THE DAY ON SATURDAY...WITH THE EXCEPTION OF SOME UPSLOPE SHOWERS POSSIBLY LASTING INTO THE EARLY AFTERNOON HOURS. ALL IN ALL...SATURDAY AND SUNDAY WILL BE QUITE PLEASANT WITH SUNNY SKIES AND TEMPS REACHING THE MID 50S AND MID 60S RESPECTIVELY. ON MONDAY...THE UPPER LEVELS TURN MORE WESTERLY TO SOUTHWESTERLY AHEAD OF A DIGGING TROUGH ACROSS THE WESTERN U.S.. AT THE SURFACE...SOUTHERLY FLOW WILL PULL IN WARM...MOIST AIR FROM THE GULF. ADDITIONALLY...BOTH THE GFS AND ECMWF INDICATE A SERIES OF DISTURBANCES THAT WILL TRACK ACROSS THE REGION...INCREASING THE CHANCES FOR RAIN AND THUNDERSTORMS AT TIMES FROM MONDAY MORNING THROUGH THE END OF THE PERIOD. BEST INSTABILITY LOOKS TO BE LATE MONDAY THROUGH EARLY WEDNESDAY PER LATEST MODEL SOUNDINGS. IN FACT... CAPE AND LI/S LOOK JUST AS IMPRESSIVE AS IT DOES IN THE SHORT TERM. HOWEVER...IT IS TOO FAR OUT TO WORK OUT THE DETAILS GIVEN MODEL DIFFERENCES. SO HAVE WENT WITH THE SUPERBLEND FOR POPS AND HAVE ALSO INCLUDED THUNDER IN THE WX GRIDS DURING THIS TIME FRAME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 152 PM EDT THU APR 2 2015 A COLD FRONT EXTENDING FROM THE LAKE SUPERIOR TO OK WILL ONLY SLOWING MOVE SOUTHEAST OVER THE NEXT 24 TO 36 HOURS. REPEATED ROUNDS OF SHOWERS AND THUNDERSTORMS WILL AFFECT THE AREA THROUGH FRIDAY. THIS AFTERNOON INTO TONIGHT VFR CONDITIONS WILL PREVAIL OUTSIDE OF SHOWER AND THUNDERSTORM AREAS...BUT AS THE FRONT MOVES SOUTHEAST WE ARE EXPECTING A GRADUAL LOWERING OF CEILINGS TONIGHT INTO FRIDAY. BY DAYBREAK FRIDAY MVFR CEILINGS ARE EXPECTED TO BE THE RULE ACROSS THE AREA. THE FRONT WILL PASS SOUTHEAST OF THE AREA FRIDAY NIGHT...WITH IMPROVING CONDITIONS BY SATURDAY. WINDS WILL BE GUSTY FROM THE SOUTHWEST THIS AFTERNOON...WITH SOME GUSTS TO NEAR 30 KNOTS ESPECIALLY IN THE NORTHERN PART OF THE FORECAST AREA. && .JKL WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH FRIDAY EVENING FOR KYZ044-050>052-058>060-068-069-079-080-083>086-104- 106>117-119. && $$ UPDATE...SBH SHORT TERM...HAL LONG TERM...JVM AVIATION...SBH
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
311 PM EDT THU APR 2 2015 .SYNOPSIS... PERIODS OF SHOWERS ARE EXPECTED TO CONTINUE THROUGH FRIDAY NIGHT AS A COLD FRONT SLOWLY TRACKS ACROSS THE AREA. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... STRONG ISENTROPIC LIFT WILL CONTINUE THE CHANCE FOR SHOWERS WITH ISOLATED THUNDERSTORMS THROUGH THE REMAINDER OF THE AFTERNOON. PER THE LATEST HI RES MODEL DATA...A BREAK IN PRECIPITATION MAY OCCUR FOR A FEW HOURS AHEAD OF THE COLD FRONT...BUT WITH LOW CONFIDENCE BASED ON THE CURRENT RADAR ACTIVITY UPSTREAM...OPTED TO KEEP POPS HIGH. THERE IS A BIT OF CLEARING JUST AHEAD OF THE NEXT LINE OF SHOWERS AND STORMS IN INDIANA BUT NOT CONFIDENT THAT IT WILL MAKE IT HERE BEFORE IT IS FILLED IN WITH MORE CONVECTION...KEEPING TEMPERATURES FROM WARMING MUCH FURTHER FOR THE REST OF THE DAY. WHILE THERE IS A LULL IN THE WIND AT THIS TIME EXCEPT IN SHOWERS... STRENGTHENING LOW LEVEL JET WILL ALLOW FOR GUSTY WINDS TO NEAR 30MPH TO BE POSSIBLE THROUGH THIS EVENING. LATEST HI RES DATA HAS THE COLD FRONT MOVING A BIT FASTER THAN PREVIOUSLY FORECAST...AS THE RUC AND HRRR HAVE IT RACING TOWARD THE REGION BY 00Z. THIS IS HAS BEEN REFLECTED IN THE POPS THROUGH THIS TIME PERIOD. UNSURE HOW MUCH THUNDER WE CAN EXPECT WITH CLOUD COVER LIMITING SURFACE INSTABILITY...SO SLIGHT CHANCE THUNDER WAS MAINTAINED IN THE GRIDS THROUGH THE FIRST HALF OF THE NIGHT. PWAT VALUES WILL CONTINUE TO INCREASE IN ADVANCE OF AND ALONG THE COLD FRONT...WHICH SHOULD ALLOW FOR SOME DECENT RAINFALL RATES...ESPECIALLY IN CONVECTION. HOWEVER...THINK THE BIGGER CONCERN WITH QPF WILL BE LATER FRIDAY AS THE NEXT WAVE APPROACHES AND RIDES ALONG THE STALLED BOUNDARY. THE COLD FRONT EXPECTED TO STALL AS IT MAKES ITS WAY INTO THE REGION OVERNIGHT...SO LOW TEMPERATURES WERE KEPT ELEVATED DESPITE RAINFALL THROUGH THE PERIOD. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... THE FRONTAL BOUNDARY THAT WILL BE SLICING ACROSS OUR AREA TONIGHT IS LIKELY TO GET HUNG UP IN NORTHERN WEST VIRGINIA ON FRIDAY. RATHER UNIDIRECTIONAL DEEP LAYER FLOW AND A SOMEWHAT SUPPORTIVE LOCATION RELATIVE TO THE UPPER JET MAXIMA SEEM TO POINT TOWARD THIS BEING THE MOST LIKELY LOCATION FOR THE FRONT TO LOSE ITS FORWARD MOMENTUM AND STALL. LIKEWISE...MODEL PRECIPITABLE WATER PLUMES INDICATE A FAIRLY WIDE RIBBON OF 1.1 TO 1.3 INCH PWATS FEEDING UP AHEAD OF THIS FRONTAL BOUNDARY THROUGH THE DAY ON FRIDAY AND INTO FRIDAY NIGHT. WITH THE FRONTAL BOUNDARY`S FIRST PUSH INTO THE AREA...SHOWERS WILL OCCUR ACROSS THE ENTIRE AREA FRIDAY...WITH INSTABILITY LIKELY TO BE MAXIMIZED ACROSS THE SOUTHEASTERN PORTIONS OF THE AREA. A FEW RUMBLES OF THUNDER WILL BE POSSIBLE HERE WITH THE FIRST PUSH OF THE FRONT INTO THE AREA. HOWEVER...AFTER THE INITIAL SHORT WAVE PULLS EASTWARD...AND THE FRONT LINGERS IN OR NEAR TO THE SOUTHERN FRINGE OF THE AREA...A COUPLE MORE WAVES ARE LIKELY TO BRING ADDITIONAL AT LEAST MODERATE PRECIPITATION TO PORTIONS OF ESPECIALLY NORTHERN WEST VIRGINIA. SUCCESSIVE BOUTS OF RAINFALL MAY LEAD TO LOCALIZED FLOODING...SO A FLOOD WATCH WAS ISSUED FOR PORTIONS OF NORTHERN WEST VIRGINIA AND WESTERN MARYLAND AS A RESULT. THE NEXT WAVE TO TRAVERSE THE FRONT WILL LIKELY OCCUR FRIDAY MORNING AS ONE WEAK SURFACE WAVE RIDES UP THE FRONT. AND YET ANOTHER STRONG PUSH OF MOISTURE AND LIFT WILL BE LIKELY TO RUN UP THE FRONT FRIDAY NIGHT. THIS LAST PUSH WILL LIKELY BE ASSOCIATED WITH MUCH DEEPER DYNAMICAL FORCING. THIS SHOULD BE MORE THAN SUFFICIENT TO DRIVE THE COLD FRONT MUCH FARTHER SOUTH IN ITS WAKE OVERNIGHT FRIDAY NIGHT INTO SATURDAY MORNING...SUCH THAT RAIN SHOULD CHANGE TO SNOW EVERYWHERE. THIS WILL END THE THREAT OF FLOODING AS WELL. MODEL TIME HEIGHT SECTIONS INDICATE VERY ABRUPT LAYER TEMPERATURE FALLS OVERNIGHT FRIDAY NIGHT. WITH DEFORMATION LIFT REMAINING ON THE NORTHWEST SIDE OF THE LAST SURFACE WAVE...AND COPIOUS MOISTURE TO STILL WORK WITH...THIS MAY ALLOW FOR ACCUMULATING SNOWS...ESPECIALLY TO THE NORTH OF PITTSBURGH AND IN THE UPSLOPE AREAS OF THE RIDGES. THIS WILL NEED TO BE MONITORED GOING FORWARD...HOWEVER IT CERTAINLY LOOKS LIKE AN ABRUPT ENDING TO THE WARM AND WET WEATHER THAT WILL PRECEDE IT. COLDER AND QUICKLY DRIER CONDITIONS ARRIVE FOR SATURDAY. YET ANOTHER SYSTEM LOOKS TO MOVE MAINLY NORTH OF THE AREA ON SUNDAY AS WARMER AIR SLOWLY RETURNS TO THE AREA AHEAD OF IT. FRIES && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... NEXT WEEK TEMPERATURES ARE FORECAST TO MODERATE TO NEAR...THEN ABOVE THE SEASONAL AVERAGES AS A SHORTWAVE RIDGE DEVELOPS OVER THE EASTERN HALF OF THE CONUS IN RESPONSE TO WESTERN STATES TROUGHING. PRECIP CHANCES WILL RISE AS THE WEEK AND TROUGH PROGRESS. THE LONG TERM PROGNOSIS WAS PRIMARILY BASED ON ADJUSTED WPC GUIDANCE. && .AVIATION /19Z THURSDAY THROUGH TUESDAY/... LINES OF SHOWERS WITH EMBEDDED THUNDER WILL CONTINUE TO CROSS THE TAF SITES THROUGH THIS EVENING IN ADVANCE OF A COLD FRONT. WHILE THE BULK OF RESTRICTIONS ARE ANTICIPATED OVERNIGHT WITH THE COLD FRONT...OCCASIONAL RESTRICTIONS IN SHOWERS MAY BE POSSIBLE THROUGH THE AFTERNOON. FOR NOW...OPTED TO CARRY THESE AS TEMPO GROUPS AND AMEND AS NEEDED FOR THUNDER WITH VERY LITTLE SURFACE INSTABILITY PRESENT. INTENSIFYING LOW LEVEL JET AND WARM ADVECTION WILL MAINTAIN A THREAT FOR WIND SHEAR TONIGHT WITH A MENTION AT EVERY TAF LOCATION UNTIL THE COLD FRONT STALLS OUT NEAR THE MASON-DIXON LINE. EXPECT SOME IMPROVEMENT FOR THE FAR NORTHERN TAF SITES BY MORNING AS THE FRONT SAGS SOUTH. ELSEWHERE...RESTRICTIONS ARE LIKELY TO CONTINUE WITH THE NEXT WAVE RIDING ALONG THE STALLED BOUNDARY FRIDAY AFTERNOON. .OUTLOOK.../FRIDAY THROUGH MONDAY/... LOW PRESSURE MOVING ALONG THE AFOREMENTIONED FRONTAL BOUNDARY WILL MAINTAIN RESTRICTIONS INTO SATURDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...FLOOD WATCH FROM 2 AM EDT FRIDAY THROUGH LATE FRIDAY NIGHT FOR MDZ001. OH...NONE. PA...NONE. WV...FLOOD WATCH FROM 2 AM EDT FRIDAY THROUGH LATE FRIDAY NIGHT FOR WVZ012-021>023-041. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1250 PM EDT THU APR 2 2015 .SYNOPSIS... SHOWER CHANCES ARE EXPECTED TO INCREASE TODAY THROUGH FRIDAY NIGHT AS A COLD FRONT SLOWLY TRACKS ACROSS THE AREA. && .NEAR TERM /THROUGH TONIGHT/... STRONG ISENTROPIC LIFT HAS ALLOWED FOR AREA OF RAIN TO CONTINUE TO HOLD STRONG AS IT MOVES INTO WESTERN PA DESPITE MOVING INTO VERY DRY AIR PER THE SURFACE DEWPOINTS. EXPECT MEASURABLE RAIN...TO ABOUT .20 INCH WITH THIS INITIAL LINE...ESPECIALLY WHERE CONVECTIVE ELEMENTS REMAIN WITH VERY LIMITED INSTABILITY. WHILE TEMPERATURES MADE IT INTO THE HIGH 60`S OVER A GOOD PORTION OF FORECAST AREA...WETBULBING FROM PRECIP WILL DROP EVERYONE BACK INTO THE 50`S. THERE IS A BIT OF CLEARING JUST AHEAD OF THE NEXT LINE OF SHOWERS AND STORMS IN INDIANA BUT NOT CONFIDENT THAT IT WILL MAKE IT HERE BEFORE IT IS FILLED IN WITH MORE CONVECTION...KEEPING TEMPERATURES FROM WARMING MUCH FURTHER FOR THE REST OF THE DAY. STRENGTHENING LOW LEVEL JET WILL ALLOW FOR GUSTY WINDS TO NEAR 30MPH POSSIBLE AS SHOWERS TAP INTO THESE HIGHER WINDS THROUGH THE EVENING. SHOWERS/STORMS AHEAD OF THE COLD FRONT ARE MOVING A BIT FASTER THAN PREVIOUSLY FORECAST...AS THE RUC AND HRRR HAVE IT RACING TOWARD THE REGION BY 00Z. THIS IS HAS BEEN REFLECTED IN THE POPS THROUGH THIS TIME PERIOD. UNSURE HOW MUCH THUNDER WE CAN EXPECT WITH CLOUD COVER LIMITING SURFACE INSTABILITY...SO SLIGHT CHANCE THUNDER WAS MAINTAINED IN THE GRIDS THROUGH THE FIRST HALF OF THE NIGHT. COLD FRONT WILL STALL AS IT MAKES ITS WAY INTO THE REGION OVERNIGHT...SO LOW TEMPERATURES WERE KEPT ELEVATED DESPITE RAINFALL THROUGH THE PERIOD. && .SHORT TERM /FRIDAY THROUGH SUNDAY/... A SURFACE WAVE IS PROGGED TO TRACK ALONG THE FRONT FROM THE MS VALLEY INTO THE OH VALLEY FRIDAY BRINGING ADDITIONAL SHOWERS TO THE AREA. ISOLATED THUNDERSTORMS ARE POSSIBLE S OF PIT AGAIN IN LIMITED INSTABILITY. THE MAIN UPPER TROUGH AXIS IS PROGGED TO CROSS THE AREA LATE FRIDAY NIGHT AND EARLY SATURDAY AS THE SURFACE LOW CONTINUES STRENGTHENING AS IT MOVES OFF THE NEW ENGLAND COAST. THIS SHOULD BRING A RAPID END TO ANY PRECIP...THOUGH A BRIEF PERIOD OF SNOW SHOWERS IS POSSIBLE AS IT ENDS. TOTAL RAINFALL AMOUNTS OF 1.25 TO 2 INCHES ARE EXPECTED THROUGH FRIDAY EVENING. THIS WILL LIKELY CAUSE RISES ON AREA RIVERS...THOUGH SIGNIFICANT HYDRO PROBLEMS ARE NOT EXPECTED AT THIS TIME. PREFERRED A BLEND OF THE GFS/ECMWF...MAINLY DUE TO THEIR HANDLING OF THE FRONTAL SURFACE WAVE...AND THE MORE REASONABLE QPF NUMBERS FROM THE ECMWF. AFTER BUILDING HIGH PRESSURE LATER SATURDAY...A WEAK SHORTWAVE IS PROGGED TO BRUSH AREAS NORTH OF I 80 WITH LOW PRECIP CHANCES ON SUNDAY. ABOVE AVERAGE TEMPS FRIDAY ARE EXPECTED TO BE REPLACED BY WELL BELOW AVERAGE READINGS SATURDAY...WITH SOME RECOVERY FOR SUNDAY. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... NEXT WEEK TEMPERATURES ARE FORECAST TO MODERATE TO NEAR...THEN ABOVE THE SEASONAL AVERAGES AS A SHORTWAVE RIDGE DEVELOPS OVER THE EASTERN HALF OF THE CONUS IN RESPONSE TO WESTERN STATES TROUGHING. PRECIP CHANCES WILL RISE AS THE WEEK AND TROUGH PROGRESS. THE LONG TERM PROGNOSIS WAS PRIMARILY BASED ON ADJUSTED WPC GUIDANCE. && .AVIATION /16Z THURSDAY THROUGH MONDAY/... LINE OF SHOWERS AND STORMS ALONG THE WARM FRONT WILL CROSS A FEW OF THE TAF SITES THROUGH MIDDAY. AT THIS POINT...HAVE ADDED VCTS TO ZZV AND WILL FURTHER AMEND AS NEEDED IF LINE HOLDS TOGETHER. THE HRRR HAS BEEN HANDLING THIS THE BEST SO TIMING WAS MAINTAINED OFF OF GUIDANCE AND RADAR TRENDS. HOWEVER...RESTRICTIONS SHOULD BE LIMITED TO PORTS WHERE A THUNDERSTORM PASSES AND GENERAL VFR IS MAINTAINED UNTIL MORE WIDESPREAD PRECIITATION IS EXPECTED LATE THIS AFTERNOON. INTENSIFYING LOW LEVEL JET AND WARM ADVECTION WILL MAINTAIN A THREAT FOR WIND SHEAR UNTIL BETTER MIXING THIS AFTERNOON. IT WILL ONCE AGAIN BE AN ISSUE TONIGHT AS WELL...AND WILL BE REINTRODUCED IN THE NEXT TAF ISSUANCE. DEGRADATION TO WIDESPREAD MVFR...AND PROBABLY EVENTUAL IFR...CAN BE EXPECTED AS RAIN BECOMES MORE WIDESPREAD WITH THE ENCROACHING FRONT OVERNIGHT. .OUTLOOK.../FRIDAY THROUGH MONDAY/... LOW PRESSURE MOVING ALONG THE AFOREMENTIONED FRONTAL BOUNDARY WILL MAINTAIN RESTRICTIONS INTO SATURDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
450 PM EDT THU APR 2 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 331 PM EDT THU APR 2 2015 ...GUSTY WINDS THIS EVENING THEN TURNING COLDER FOR FRIDAY... LOW PRESSURE SYSTEM WITH MSLP AROUND 989MB TRACKING ACROSS NORTHERN ONTARIO HAS PUSHED A TROUGH ACROSS UPR MICHIGAN. AREA OF RAIN ALONG THE TROUGH ENHANCED BY RIGHT ENTRANCE OF JET STREAK HAS PUSHED EAST OF CWA AND CLEARING SKIES ARE STEADILY SPREADING WEST TO EAST OVER CWA. WESTERLY WINDS AND DEEP MIXING HAVE ALLOWED TEMPS TO RISE WELL INTO THE 50S MUCH OF CWA...EXCEPT IN THE EAST WITH LATER DEPARTURE OF CLOUDS AND RAIN. CONCERN INITIALLY IS ON WINDS OVER THE WEST CWA LATE THIS AFTN AND EVENING. ALREADY PUT OUT SPS TO COVER THE GUSTY WINDS AS 12Z NAM AND LATEST RAP SOUNDINGS INDICATED GUSTS COULD EXCEED 40 KTS. HAVE BEEN WATCHING UPSTREAM TO SEE HOW HIGH WINDS HAVE GUSTED AND THUS FAR AS OF 18Z...WINDS HAVE BEEN PEAKING NEAR 40 KTS OVER HIGHER TERRAIN OF NORTHEAST MN. THIS EQUATES TO MIXING HEIGHT AROUND 800MB OR 7000FT AGL. EXTRAPOLATING THESE TRENDS ALONG WITH LATEST RAP/HRRR AND NAM OUTPUT...WOULD EXPECT A PERIOD OF GUSTS OVER 40 KTS OVER FAR WEST CWA 20Z-24Z...VCNTY OF KIWD...AND ALSO THE HIGHER TERRAIN OF THE COPPER COUNTRY. INSTEAD OF ISSUING A SHORT DURATION WIND ADVY...WILL CONTINUE WITH SPECIAL WEATHER STATEMENT TO COVER THE GUSTIER WINDS. THINKING IS THAT ADVY LEVEL GUSTS WILL OVERALL BE ISOLD DUE TO LACK OF COLD AIR ADVECTION IN THE MIXED LAYER AND NO REAL PRESSURE RISE TO ENHANCE THE GRADIENT WINDS AND AS STRONGER WINDS ALOFT DO NOT ARRIVE UNTIL AFTER MAXIMUM PEAK DAYTIME HEATING. WILL BE CLOSE THOUGH. CARRIED GUSTIER WEST WINDS OVER ROUGHLY WEST HALF OF CWA INTO EARLY EVENING BEFORE DIMINISHING WINDS BY LATER EVENING AS BLYR COOLS AND STABILITY INCREASES. GUSTY WINDS AND RH VALUES FALLING BLO 20 PCT OVER THE WEST WILL ALSO LEAD TO FIRE WX CONCERNS INTO EARLY EVENING. WILL CONTINUE TO NOT ISSUE ANY FIRE WX PRODUCTS THOUGH AS EVEN FOR THE AREAS NOW FREE OF SNOW...SOILS ARE STILL FAIRLY MOIST DUE TO RECENT RAIN AND OVERALL COOLER/WETTER STRETCH OF WEATHER. THIS WAS DISCUSSED WITH FIRE WX CUSTOMERS ON WED AFTN. COLD FRONT WHICH CURRENTLY EXTENDS TO SOUTHWEST OF SFC LOW ACROSS THE DAKOTAS ARRIVES OVERNIGHT. W WINDS SHIFTING NORTHWEST OVERNIGHT INTO FRIDAY MORNING SHOULD BE STRONGEST CLOSER TO LK SUPERIOR. MAY SEE GUSTS OVER 30 MPH MAINLY TO THE EAST OF MARQUETTE. A LOT OF LOW CLOUDS UPSTREAM IN WAKE OF THE COLD FRONT. PRETTY CHILLY IN WAKE OF THE COLD FRONT OVER SCNTRL CANADA THIS AFTN WITH SINGLE DIGITS AND TEENS OVER MUCH OF SASKATCHEWAN AND MANITOBA. MODEL SOUNDINGS FOR LATER TONIGHT INTO FRIDAY SHOW A LOT OF MOISTURE BLO H85...BUT WITH INVERSIONS MAINLY BLO H85 AND A LOT OF DRY AIR ABOVE ALONG WITH QUICKLY INCREASING ANTICYCLONIC SFC FLOW...LAKE EFFECT SNOW POTENTIAL SEEMS MARGINAL AT BEST GIVEN H85 TEMPS -10C TO -12C. WILL CONTINUE THE ISOLD POPS FOR LGT SNOW SHOWERS. THERMAL TROUGH LINGERS INTO MUCH OF THE DAY ON FRIDAY...SO KEPT BKN-OVC CLOUDS INTO AFTN BEFORE THE HIGH CLEARS OUT THE SKIES BY LATE AFTN. WILL BE QUITE THE SWING IN TEMPS COMPARED TO TODAY...WITH HIGHS ON FRIDAY STAYING IN THE UPR 20S TO LWR 30S OVER THE NORTHERN U.P. AND MAYBE REACHING LOWER 40S IN THE FAR SCNTRL. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 450 PM EDT THU APR 2 2015 FRI NIGHT INTO SAT...PCPN CHANCES WILL INCREASE AGAIN LATE FRI NIGHT INTO SATURDAY AS MODELS SHOW A WEAK CLIPPER SHRTWV MOVING THROUGH THE NRN LAKES. HOWEVER...WITH ONLY LIMITED MOISTURE AVAILABLE IN A NW FLOW AND FAIRLY WEAK FORCING INDICATED...ONLY SLIGHT CHANCE TO LOW CHANCE POPS (20 TO 30 PCT) WERE MENTIONED. ANY SNOWFALL AMOUNTS SHOULD AMOUNT TO LESS THAN A HALF INCH. IF PCPN OCCURS SOUTH CENTRAL IT COULD BRIEFLY MIX WITH RAIN. SUN...MOST OF THE 12Z MODELS NOW SEEM TO BE TRENDING FARTHER NORTH PER PAST FEW RUNS OF ECMWF WITH SHORTWAVE MOVING THROUGH THE UPPER GREAT LAKES. MOST OF THE MODELS ALSO INDICATE SFC-850 MB WARM FRONT DEVELOPING OVER WI WHICH WOULD SUPPORT AN AREA OF SNOW ACROSS UPPER MICHIGAN AIDED BY UPPER LEVEL DIV IN THE RIGHT ENTRANCE OF A 250-300 MB JET MAX E OF LAKE SUPERIOR. THE 12Z GFS IS STILL FURTHER SOUTH THAN THE ECMWF/GEM-NH/NAM MODEL BLEND AND WOULD SUGGEST SNOW WOULD BE CONFINED TO MAINLY SCNTRL UPPER MI. HAVE DECIDED TO USE A MODEL CONSENSUS FOR QPF ACROSS THE FCST AREA RANGING FROM LESS THAN .10 INCH ACROSS THE FAR WEST AND NORTH TO NEAR .20 INCH AT KMNM. GIVEN NEAR 10 TO 1 SLR/S EXPECTED COULD SEE 1 TO 2 INCHES OF WET SNOW FROM SUNDAY INTO SUNDAY EVENING WITH THE GREATEST AMOUNTS JUST INLAND FROM THE BAY OF GREEN BAY AND LAKE MI AND OVER THE FAR EAST. MON-TUE...AS A TROUGH DIGS INTO THE WRN CONUS THE RESULTING SW FLOW AND STRENGTHENING WAA PATTERN FROM THE PLAINS INTO THE GREAT LAKES SHOULD BRING MORE PCPN INTO THE NRN LAKES MAINLY FOR MON NIGHT INTO TUE. MOST OF THE MODELS ADVERTISE DRY WEATHER THROUGH MUCH OF THE DAY ON MON AS A CONFLUENT FLOW INTO NRN ONTARIO WILL RESULT IN MORE DOMINANT SFC RDGG AND DRIER CONDITIONS INTO THE NRN LAKES. ARRIVAL OF SHORTWAVE ENERGY EJECTING NE AHEAD OF DEVELOPING WRN CONUS TROF WILL BRING THE PLAINS SFC LOW AND ASSOC WARM FRONT SLIGHTLY FARTHER NORTH AND SHOULD ALLOW FOR SOME SNOW TO SPREAD INTO PORTIONS OF UPPER MI MON NIGHT INTO TUE. MODEL CONSENSUS FAVORS CHANCE POPS ESPECIALLY INTO THE SOUTHERN PORTION OF UPPER MI LATE MON INTO TUE WITH MAINLY DRY CONDITIONS OVER THE NRN CWA. TUE NIGHT INTO THU...THE 12Z ECMWF SHOWS QUITE A DEPARTURE FROM ITS PREV COUPLE OF RUNS. AFTER SHOWING STRONGER CONFLUENT FLOW ALOFT AND DRIER CONDITIONS FOR MON INTO TUE...IT THEN EJECTS A STRONGER SHORTWAVE FROM THE WRN CONUS TROF NE TOWARD THE WRN GREAT LAKES FOR LATE WED INTO THU. IN TURN...THE DEVELOPING SFC LOW TRACKS MUCH FARTHER NORTH AND WEST THROUGH CENTRAL LOWER MI THAN PREV RUNS. THIS SOLN BRINGS AN AREA OF WAA PCPN INTO UPPER MI MAINLY WED AFTERNOON INTO EARLY THU. ECMWF CRITICAL THICKNESSES SUGGEST PCPN COULD BE MOSTLY IN THE FORM OF RAIN OR A MIX OF RAIN/SNOW OVER THE EAST HALF OF THE CWA. THIS OBVIOUSLY WILL BE SOMETHING TO KEEP AN EYE ON FOR FUTURE MODEL RUNS AND TO SEE IF MODEL TRENDS WOULD EVENTUALLY SUPPORT A WETTER FCST FOR THIS TIME FRAME. BUT FOR NOW WILL CONTINUE WITH THE IDEA OF DRIER CONDITIONS TUE NIGHT INTO THU AS BOTH THE GFS AND GEM-NH HAVE BEEN CONSISTENT WITH PREV RUNS SHOWING A SFC HIGH PRES RIDGE BUILDING IN FM NORTH OF LAKE SUPERIOR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 151 PM EDT THU APR 2 2015 GUSTY WEST WINDS...OVER 30 KTS AT KIWD AND KCMX...WILL BE MAIN STORY INTO THIS EVENING. SKIES WILL CONTINUE TO CLEAR FROM WEST TO EAST. MVFR LOW CLOUDS ARE LURKING UPSTREAM THOUGH AND THESE WILL MOVE OVER THE REGION OVERNIGHT TONIGHT INTO FRIDAY. COULD BE A FEW LAKE EFFECT SNOW SHOWERS AT KIWD LATE TONIGHT AS COLDER AIR FLOWS ACROSS LK SUPERIOR. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 331 PM EDT THU APR 2 2015 WEST TO SOUTHWEST GALES TO 40 KTS EXPECTED OVER PORTIONS OF WEST AND NCNTRL LK SUPERIOR THIS EVENING...THEN WINDS SHIFT TO THE NORTHWEST AND COULD STILL REACH GALES OVER MAINLY CNTRL LK SUPERIOR OVERNIGHT. NORTHWEST WINDS TO 30 KTS ON FRIDAY...STRONGEST OVER EASTERN LK SUPERIOR. HIGH PRESSURE THEN EXPANDS FM CNTRL CANADA TO THE UPPER GREAT LAKES THIS WEEKEND INTO EARLY NEXT WEEK. EXPECT WINDS THROUGH THIS TIME TO STAY AT OR BLO 25 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 2 AM EDT /1 AM CDT/ FRIDAY FOR LSZ162. GALE WARNING UNTIL 5 AM EDT FRIDAY FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...VOSS AVIATION...JLA MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
336 PM EDT THU APR 2 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 331 PM EDT THU APR 2 2015 ...GUSTY WINDS THIS EVENING THEN TURNING COLDER FOR FRIDAY... LOW PRESSURE SYSTEM WITH MSLP AROUND 989MB TRACKING ACROSS NORTHERN ONTARIO HAS PUSHED A TROUGH ACROSS UPR MICHIGAN. AREA OF RAIN ALONG THE TROUGH ENHANCED BY RIGHT ENTRANCE OF JET STREAK HAS PUSHED EAST OF CWA AND CLEARING SKIES ARE STEADILY SPREADING WEST TO EAST OVER CWA. WESTERLY WINDS AND DEEP MIXING HAVE ALLOWED TEMPS TO RISE WELL INTO THE 50S MUCH OF CWA...EXCEPT IN THE EAST WITH LATER DEPARTURE OF CLOUDS AND RAIN. CONCERN INITIALLY IS ON WINDS OVER THE WEST CWA LATE THIS AFTN AND EVENING. ALREADY PUT OUT SPS TO COVER THE GUSTY WINDS AS 12Z NAM AND LATEST RAP SOUNDINGS INDICATED GUSTS COULD EXCEED 40 KTS. HAVE BEEN WATCHING UPSTREAM TO SEE HOW HIGH WINDS HAVE GUSTED AND THUS FAR AS OF 18Z...WINDS HAVE BEEN PEAKING NEAR 40 KTS OVER HIGHER TERRAIN OF NORTHEAST MN. THIS EQUATES TO MIXING HEIGHT AROUND 800MB OR 7000FT AGL. EXTRAPOLATING THESE TRENDS ALONG WITH LATEST RAP/HRRR AND NAM OUTPUT...WOULD EXPECT A PERIOD OF GUSTS OVER 40 KTS OVER FAR WEST CWA 20Z-24Z...VCNTY OF KIWD...AND ALSO THE HIGHER TERRAIN OF THE COPPER COUNTRY. INSTEAD OF ISSUING A SHORT DURATION WIND ADVY...WILL CONTINUE WITH SPECIAL WEATHER STATEMENT TO COVER THE GUSTIER WINDS. THINKING IS THAT ADVY LEVEL GUSTS WILL OVERALL BE ISOLD DUE TO LACK OF COLD AIR ADVECTION IN THE MIXED LAYER AND NO REAL PRESSURE RISE TO ENHANCE THE GRADIENT WINDS AND AS STRONGER WINDS ALOFT DO NOT ARRIVE UNTIL AFTER MAXIMUM PEAK DAYTIME HEATING. WILL BE CLOSE THOUGH. CARRIED GUSTIER WEST WINDS OVER ROUGHLY WEST HALF OF CWA INTO EARLY EVENING BEFORE DIMINISHING WINDS BY LATER EVENING AS BLYR COOLS AND STABILITY INCREASES. GUSTY WINDS AND RH VALUES FALLING BLO 20 PCT OVER THE WEST WILL ALSO LEAD TO FIRE WX CONCERNS INTO EARLY EVENING. WILL CONTINUE TO NOT ISSUE ANY FIRE WX PRODUCTS THOUGH AS EVEN FOR THE AREAS NOW FREE OF SNOW...SOILS ARE STILL FAIRLY MOIST DUE TO RECENT RAIN AND OVERALL COOLER/WETTER STRETCH OF WEATHER. THIS WAS DISCUSSED WITH FIRE WX CUSTOMERS ON WED AFTN. COLD FRONT WHICH CURRENTLY EXTENDS TO SOUTHWEST OF SFC LOW ACROSS THE DAKOTAS ARRIVES OVERNIGHT. W WINDS SHIFTING NORTHWEST OVERNIGHT INTO FRIDAY MORNING SHOULD BE STRONGEST CLOSER TO LK SUPERIOR. MAY SEE GUSTS OVER 30 MPH MAINLY TO THE EAST OF MARQUETTE. A LOT OF LOW CLOUDS UPSTREAM IN WAKE OF THE COLD FRONT. PRETTY CHILLY IN WAKE OF THE COLD FRONT OVER SCNTRL CANADA THIS AFTN WITH SINGLE DIGITS AND TEENS OVER MUCH OF SASKATCHEWAN AND MANITOBA. MODEL SOUNDINGS FOR LATER TONIGHT INTO FRIDAY SHOW A LOT OF MOISTURE BLO H85...BUT WITH INVERSIONS MAINLY BLO H85 AND A LOT OF DRY AIR ABOVE ALONG WITH QUICKLY INCREASING ANTICYCLONIC SFC FLOW...LAKE EFFECT SNOW POTENTIAL SEEMS MARGINAL AT BEST GIVEN H85 TEMPS -10C TO -12C. WILL CONTINUE THE ISOLD POPS FOR LGT SNOW SHOWERS. THERMAL TROUGH LINGERS INTO MUCH OF THE DAY ON FRIDAY...SO KEPT BKN-OVC CLOUDS INTO AFTN BEFORE THE HIGH CLEARS OUT THE SKIES BY LATE AFTN. WILL BE QUITE THE SWING IN TEMPS COMPARED TO TODAY...WITH HIGHS ON FRIDAY STAYING IN THE UPR 20S TO LWR 30S OVER THE NORTHERN U.P. AND MAYBE REACHING LOWER 40S IN THE FAR SCNTRL. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 511 AM EDT THU APR 2 2015 FRI...CAA IN THE WAKE OF THE FRONT WILL DROP 850 MB TEMPS TO AROUND -12C BY 12Z/FRI. WITH INVERSION HEIGHTS DROPPING BELOW 4K FT AND MARGINAL INSTABILITY FOR LES...THE FCST MAINTAINS ONLY SLIGHT CHANCE POPS EARLY FOR NORTH CENTRAL AND WEST LOCATIONS FAVROED BY NNW FLOW. EXTENSIVE ICE COVER LINGERING OVER MUCH OF EASTERN LAKE SUPERIOR WILL LIMIT ANY LES POTENTIAL OVER THE ERN CWA. WITH MUCH COLDER AIR MOVING IN EXPECT FRIDAYS HIGH TEMPS IN THE LOWER TO MID 30S...ABOUT 25 DEGREES LOWER THAN THURSDAY. FRI NIGHT INTO SAT...PCPN CHANCES WILL INCREASE AGAIN LATE FRI NIGHT INTO SATURDAY AS MODELS SHOW ANOTHER WEAK CLIPPER SHRTWV MOVING THROUGH THE NRN LAKES. HOWEVER...WITH ONLY LIMITED MOISTURE AVAILABLE IN A NW FLOW AND FAIRLY WEAK FORCING INDICATED...ONLY SLIGHT CHANCE POPS WERE MENTIONED. ANY SNOWFALL AMOUNTS SHOULD AMOUNT TO LESS THAN A HALF INCH. IF PCPN OCCURS SOUTH CENTRAL IT COULD BRIEFLY MIX WITH RAIN. SUN...STILL PLENTY OF MODEL DIFFERENCES AND LOWER FCST CONFIDENCE. THE 12Z/01 AND 00Z/02 ECMWF SHOW A MORE PROMINENT SFC-850 MB WARM FRONT OVER WI DEVELOPING WHICH WOULD SUPPORT AN AREA OF SNOW ACROSS UPPER MICHIGAN AS A SHORTWAVE MOVES THROUGH THE AREA AND UPPER LEVEL DIV INCREASES WITH THE RIGHT ENTRANCE OF A JET E OF LAKE SUPERIOR. THE GFS AND GEM KEEP THESE FEATURES AND THE RESULTING PCPN FARTHER SOUTH. MON-WED...AS A TROUGH DIGS INTO THE WRN CONUS THE RESULTING SW FLOW THROUGH THE PLAINS TOWARD THE GREAT LAKES AND WAA PATTERN COULD BRING ADDITIONAL PCPN TO THE NRN LAKES. THE 00Z/02 ECMWF STILL SHOWS CONFLUENT FLOW AND DRIER CONDITIONS INTO THE NRN LAKES ON MON SIMILAR TO THE 12Z/01 RUN...BUT BEGINS TO TREND FARTHER NORTH WITH PLAINS SYSTEM FOR MON NIGHT INTO TUE NIGHT BRINGING PCPN INTO THE AREA. THE 00Z GFS AND GEM-NH CONTINUE TO BRING THE PLAINS SFC LOW AND ASSOC WARM FRONT AND SNOW FARTHER NORTH...SPREADING SNOW INTO UPPER MI MON. MODELS CONSENSUS FAVORS AT LEAST CHANCE POPS INTO THE UPPER MI MON AND ESPECAILLY MON NIGHT INTO TUE WITH THE GREATEST PCPN CHANCES OVER THE SOUTH. EXPECTED DRIER WEATHER BY TUE NIGHT INTO WED AS BOTH ECMWF AND GFS HAVE HIGH PRES RIDGE BUILDING IN FM NORTH OF LAKE SUPERIOR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 151 PM EDT THU APR 2 2015 GUSTY WEST WINDS...OVER 30 KTS AT KIWD AND KCMX...WILL BE MAIN STORY INTO THIS EVENING. SKIES WILL CONTINUE TO CLEAR FROM WEST TO EAST. MVFR LOW CLOUDS ARE LURKING UPSTREAM THOUGH AND THESE WILL MOVE OVER THE REGION OVERNIGHT TONIGHT INTO FRIDAY. COULD BE A FEW LAKE EFFECT SNOW SHOWERS AT KIWD LATE TONIGHT AS COLDER AIR FLOWS ACROSS LK SUPERIOR. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 331 PM EDT THU APR 2 2015 WEST TO SOUTHWEST GALES TO 40 KTS EXPECTED OVER PORTIONS OF WEST AND NCNTRL LK SUPERIOR THIS EVENING...THEN WINDS SHIFT TO THE NORTHWEST AND COULD STILL REACH GALES OVER MAINLY CNTRL LK SUPERIOR OVERNIGHT. NORTHWEST WINDS TO 30 KTS ON FRIDAY...STRONGEST OVER EASTERN LK SUPERIOR. HIGH PRESSURE THEN EXPANDS FM CNTRL CANADA TO THE UPPER GREAT LAKES THIS WEEKEND INTO EARLY NEXT WEEK. EXPECT WINDS THROUGH THIS TIME TO STAY AT OR BLO 25 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 2 AM EDT /1 AM CDT/ FRIDAY FOR LSZ162. GALE WARNING UNTIL 5 AM EDT FRIDAY FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...JLB AVIATION...JLA MARINE...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1215 PM EDT THU APR 2 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS EXPECTED TODAY WITH PERHAPS SOME RUMBLES OF THUNDER. MODERATE TO BRIEF HEAVY RAINFALL...ALONG WITH GUSTY WINDS CANNOT BE RULED OUT INTO THE AFTERNOON AS A COLD FRONT SWEEPS THROUGH THE REGION...BUT SEVERE WEATHER IS NOT EXPECTED. MUCH COOLER WEATHER MOVES IN TONIGHT INTO THE WEEKEND...AND ACTIVE WEATHER IS EXPECTED TO CONTINUE. RAIN CHANCES RETURN FRIDAY AFTERNOON ACROSS SOUTHERN LOWER MICHIGAN WITH A CHANCE FOR A RAIN/SNOW MIX FRIDAY NIGHT. FREQUENT BOUTS OF PRECIPITATION ARE EXPECTED SUNDAY INTO THE MIDDLE OF NEXT WEEK. && .UPDATE... ISSUED AT 1145 AM EDT THU APR 2 2015 NO CHANGES TO THE GOING FORECAST ALTHOUGH IT APPEARS THE RISK OF THUNDER MAY BE DWINDLING. THE INITIAL WARM ADVECTION SURGE TOUCHED OFF A FEW TSTMS EARLIER THIS MORNING BUT LATEST TSTM ACTIVITY IS CURRENTLY FAVORING THE BETTER INSTABILITY SOUTH OF THE MI BORDER. THE MAIN CHANCE OF A FEW RUMBLES SHOULD BE SOUTH AND EAST OF GRR THROUGH 21Z WHERE NEAR ZERO TO SLIGHTLY NEGATIVE H8-H5 THETA-E LAPSE RATES EXIST. DESPITE THE LIMITED THUNDER THREAT... OVERALL COVERAGE OF RAIN SHOWERS IS EXPECTED TO INCREASE OVER THE NEXT COUPLE HOURS AS THE FRONT COMES THROUGH. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 329 AM EDT THU APR 2 2015 PERIODS OF RAIN SHOWERS WITH PERHAPS A RUMBLE OF THUNDER TODAY FOLLOWED BY MUCH COOLER WEATHER FRIDAY AND SATURDAY. A DRY VERTICAL PROFILE IS NOTED ON A 05Z RAP SOUNDING...BUT HEALTHY MID LEVEL MOISTURE ADVECTION WILL OCCUR FROM THIS WRITING THROUGH THE NEXT SEVERAL HOURS. H925 TO H850 LAYER WAA IS ALSO ONGOING DURING THIS TIMEFRAME WITH STRONG SOUTHWESTERLY FLOW AHEAD OF THE H850 THERMAL TROUGH. AT THE LOW LEVELS...MUCH HIGHER THETA E AIR ADVECTS IN AFTER 12Z THIS MORNING JUST AHEAD OF THE SURFACE COLD FRONT. DEWPOINTS IN THE LOWER 50S ARE EXPECTED THIS AFTERNOON ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. A WEAK SHORTWAVE NOTED OVER WESTERN IL ON WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NORTHEAST INTO OUR AREA BUT LOSE SOME OF ITS PUNCH. NEVERTHELESS...WEAK ELEVATED INSTABILITY IS PRESENT AT THE TIME OF ITS ARRIVAL AROUND 12Z. RAIN CHANCES...WITH PERHAPS A RUMBLE OF THUNDER...INCREASE AFTER 11Z. THE COLD FRONT TRACKS THROUGH THE CWA BETWEEN 16-22Z. DIURNAL HEATING JUST PRIOR TO THIS FRONTAL PASSAGE WILL GIVE MOST AREAS THEIR BEST CHANCE FOR THUNDER AND ASSOCIATED NON-SEVERE THREATS...SUCH AS MODERATE TO BRIEF HEAVY RAIN...GUSTY WINDS...AND LIGHTNING. INSTABILITY IS MARGINAL AT BEST...BUT HIGHEST SOUTH OF I-96. 0-6 KM BULK SHEAR INCREASES THROUGHOUT THE DAY...WITH VALUES OF AROUND 35-45 KNOTS SOUTH OF I-96 AT 18Z. BOTTOM LINE...RAIN SHOWERS WITH A CHANCE OF THUNDER INTO THE AFTERNOON. BEHIND THE FRONT...DRY WEATHER EXPECTED TONIGHT WITH LOWS IN THE 30S TO AROUND 40 DEGREES. ANOTHER PV ANOMALY AND SHORTWAVE MOVE INTO THE AREA TOMORROW...SUPPORTING MAINLY A CHANCE OF RAIN ACROSS THE SOUTHERN FORECAST AREA FRIDAY AFTERNOON AND A MIX OF RAIN AND SNOW FRIDAY NIGHT. LOWER MI IS IN A FAVORABLE POSITION WITHIN A COUPLED UPPER JET STRUCTURE DURING THIS TIMEFRAME...MEANING GOOD UPPER DIVERGENCE IS RESPONSIBLE FOR STRENGTHENING OF THE MIDLEVEL SHORTWAVE. LOWS FRIDAY NIGHT ARE EXPECTED TO PLUMMET INTO THE UPPER TEENS AND 20S. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 329 AM EDT THU APR 2 2015 LOOKS LIKE AN ACTIVE STORM TRACK SETTING UP IN THE EXTENDED PERIOD WITH FREQUENT BOUTS OF PRECIPITATION...INCLUDING SOME SNOW AT TIMES. A PLAINS LOW MOVES EAST TOWARDS THE GREAT LAKES SATURDAY NIGHT AND ISENTROPIC ASCENT OUT AHEAD OF IT SHOULD RESULT IN SOME LIGHT SNOW AND RAIN SATURDAY NIGHT. IT TAKES UNTIL MONDAY AFTERNOON BEFORE THE COLD AIR HAS ERODED ENOUGH TO ALLOW FOR A FORECAST OF ALL RAIN ACROSS THE ENTIRE FORECAST AREA. BEST CHANCE FOR STEADY RAIN WILL BE ON MONDAY NIGHT AS THE SFC WAVE TRACKS ALONG THE FRONT DRAPED ACROSS LOWER MICHIGAN. A SECOND WAVE PROLONGS THE PRECIP INTO TUESDAY NIGHT...AND ENOUGH COLD AIR RETURNS TO BRING THE POSSIBILITY OF A MIX ACROSS THE NORTHERN FORECAST AREA BEFORE THE PRECIP TAPERS OFF ON WEDNESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY) ISSUED AT 1215 PM EDT THU APR 2 2015 A MIX OF MAINLY MVFR/IFR CONDITIONS IS ANTICIPATED THIS AFTERNOON DUE TO LOW CLOUDS AND SCATTERED SHOWERS. SOUTHWEST WINDS WILL GUST TO 20 TO 25 KTS AT TIMES THROUGH THE AFTERNOON. CONDITIONS WILL GRADUALLY IMPROVE TO VFR LATER THIS EVENING AND OVERNIGHT AND WEST WINDS WILL SUBSIDE TO BLO 10 KTS. VFR CONDITIONS WILL THEN CONTINUE THROUGH 18Z FRIDAY. && .MARINE... ISSUED AT 358 AM EDT THU APR 2 2015 SOUTH WINDS TO 30 KNOTS THIS MORNING WILL VEER SOUTHWESTERLY AT 10 TO 20 KNOTS IN THE AFTERNOON. 3 TO 5 FOOT WAVES TODAY WILL SUBSIDE TO 1 TO 2 FEET THIS EVENING. A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH 2 PM FOR THE NEARSHORE WATERS. PERIODS OF RAIN ARE EXPECTED TODAY ALONG WITH A CHANCE FOR THUNDER AS A COLD FRONT SWEEPS THROUGH. THE RAIN WILL MOVE OUT THIS AFTERNOON. SOUTHWEST WINDS AROUND 10 KNOTS WILL VEER WESTERLY TONIGHT. NORTHERLY WINDS AT 10 TO 20 KNOTS ARE EXPECTED ON FRIDAY...RESULTING IN WAVES BUILDING SOMEWHAT. && .HYDROLOGY... ISSUED AT 1123 AM EDT THU APR 2 2015 LITTLE OR NO RISES ARE BEING NOTED ON AREA RIVERS TODAY AND WITHIN THE NEAR FUTURE. MINOR WITHIN BANK RISES MAY OCCUR AS WE PROGRESS THROUGH THE WEEK. MAINLY LIGHT TO MODERATE RAINFALL IS AFFECTING THE AREA TODAY WITH A FEW POCKETS OF BRIEF HEAVY RAINFALL. THE HEAVIER RAIN HAS BEEN LOCALIZED AND DIRECTLY ASSOCIATED WITH THUNDERSTORMS. THIS IS EXPECTED TO COME TO AN END LATE TODAY BUT THE REMAINDER OF THE WEEK WILL REMAIN RATHER ACTIVE. LIGHT RAIN IS POSSIBLE FRIDAY AND COULD MIX WITH SNOW FRIDAY NIGHT. ANOTHER SYSTEM WILL BRING MORE GENEROUS AMOUNTS OF MOISTURE TO THE AREA BY THE END OF THE WEEKEND AND INTO EARLY NEXT WEEK. NEAR THE END OF THE 7 DAY PERIOD...YET ANOTHER WAVE OF MOISTURE MOVES THROUGH. PRECIPITATION TOTALS THROUGH THE NEXT WEEK MAY EXCEED AN INCH THROUGHOUT THE FORECAST AREA. RESPONSE TIMES BETWEEN EPISODES OF PRECIPITATION SHOULD ALLOW FOR ONLY MINOR RISES TO OCCUR. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>849. && $$ UPDATE...MEADE SYNOPSIS...EBW SHORT TERM...EBW LONG TERM...OSTUNO AVIATION...LAURENS HYDROLOGY...JAM MARINE...EBW
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
542 PM CDT Thu Apr 2 2015 .DISCUSSION... Issued at 415 PM CDT THU APR 2 2015 Tonight - Friday: A frontal boundary which passed southeast through the CWA this morning lies from southeast KS through east central MO. Scattered convection will initially form along this boundary late this afternoon and early evening. However, our weather will likely be dictated by a stationary h8 front which is progged to lie across the southern CWA. Increasing isentropic ascent on the 300K and 305K surfaces will allow better moisture and weak instability to flow northward into the CWA overnight. Satellite imagery shows rapid drying occurring through the Central Rockies into northwest KS indicating the presence of a pronounced upper level jet streak. Operational models indicate a 130-140kt 250mb jet max will stretch eastward through MO tonight/Friday allowing strung out energy to flow eastward. Initially model soundings indicate extensive/thickening mid cloud production and skinny CAPE. A very dry sub-cloud region will initially absorb the precipitation which falls across KS and western MO later this evening but believe the the sounding will saturate faster than anticipated due to the moderately strong isentropic ascent and jet energy. Have increased PoPs later this evening and through the night into Friday morning to support the above scenario. Will also need to keep an eye out for small scale bowing segments which the HRRR zips ese across central KS and west central MO late this evening. The HRRR as well as a couple of other short-range convective allowing models have generated such systems. With 0-6km shear of 60-70kts any such storm will have the potential to generate damaging winds and low-end severe hail. The rain will end from west to east Friday morning and exit the eastern CWA by early afternoon. increasing surface pressure gradient will generate strong/gusty winds for most of the day and keep temperatures well below average. Saturday - Sunday: Still expect a rather quiet weekend with weak ridging aloft with southerly boundary layer winds. Sunday max temperatures may be too pessimistic but is based on increasing cloud cover as an upper system tracks through KS/OK. Could see some light precipitation nose into the southern CWA later in the day Sunday. Sunday night - Thursday: Medium range models continue to support the unsettled pattern referred to yesterday for this period. A general upper trough set up over the western U.S and pressure falls over the Southern/Central Plains will allow a warm sector to set up east of the Rockies with the southerly low-level jet tapping into the moisture from the Gulf of Mexico. A frontal boundary with a pronounced dry slot over the plains looks like the finishing touches for a typical set-up for severe weather. Timing is difficult this far out but suspect there will be one or two days where severe storms could visit our CWA. && .AVIATION...(For the 00Z TAFS through 00Z Friday Evening) Issued at 525 PM CDT THU APR 2 2015 VFR conditions initially, though cloud cover will begin to creep in as the evening progresses. A wave of activity will push through overnight, with mostly light rain expected, though nearby convective activity to the south may lead to some isolated thunderstorms. Expecting to see MVFR cigs by early Friday morning. Precip will exit the area early Friday afternoon, though strong backing winds with gusts up to 25 kts to 30 kts will persist through the remainder of the period. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...MJ AVIATION...Welsh
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
416 PM CDT Thu Apr 2 2015 .DISCUSSION... Issued at 415 PM CDT THU APR 2 2015 Tonight - Friday: A frontal boundary which passed southeast through the CWA this morning lies from southeast KS through east central MO. Scattered convection will initially form along this boundary late this afternoon and early evening. However, our weather will likely be dictated by a stationary h8 front which is progged to lie across the southern CWA. Increasing isentropic ascent on the 300K and 305K surfaces will allow better moisture and weak instability to flow northward into the CWA overnight. Satellite imagery shows rapid drying occurring through the Central Rockies into northwest KS indicating the presence of a pronounced upper level jet streak. Operational models indicate a 130-140kt 250mb jet max will stretch eastward through MO tonight/Friday allowing strung out energy to flow eastward. Initially model soundings indicate extensive/thickening mid cloud production and skinny CAPE. A very dry sub-cloud region will initially absorb the precipitation which falls across KS and western MO later this evening but believe the the sounding will saturate faster than anticipated due to the moderately strong isentropic ascent and jet energy. Have increased PoPs later this evening and through the night into Friday morning to support the above scenario. Will also need to keep an eye out for small scale bowing segments which the HRRR zips ese across central KS and west central MO late this evening. The HRRR as well as a couple of other short-range convective allowing models have generated such systems. With 0-6km shear of 60-70kts any such storm will have the potential to generate damaging winds and low-end severe hail. The rain will end from west to east Friday morning and exit the eastern CWA by early afternoon. increasing surface pressure gradient will generate strong/gusty winds for most of the day and keep temperatures well below average. Saturday - Sunday: Still expect a rather quiet weekend with weak ridging aloft with southerly boundary layer winds. Sunday max temperatures may be too pessimistic but is based on increasing cloud cover as an upper system tracks through KS/OK. Could see some light precipitation nose into the southern CWA later in the day Sunday. Sunday night - Thursday: Medium range models continue to support the unsettled pattern referred to yesterday for this period. A general upper trough set up over the western U.S and pressure falls over the Southern/Central Plains will allow a warm sector to set up east of the Rockies with the southerly low-level jet tapping into the moisture from the Gulf of Mexico. A frontal boundary with a pronounced dry slot over the plains looks like the finishing touches for a typical set-up for severe weather. Timing is difficult this far out but suspect there will be one or two days where severe storms could visit our CWA. && .AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon) Issued at 1242 PM CDT THU APR 2 2015 Generally VFR conditions through this evening. South of Kansas City, scattered late afternoon/early evening convection expected along/just north of a stalled front from west central through central MO. Later tonight areas of rain expected to form over KS and spread across most of the region towards sunrise and continue through the morning. Initially VFR ceilings but after several hours of rain should see MVFR ceilings form as winds ramp up from the north and become quite gusty. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ UPDATE...MJ DISCUSSION...MJ AVIATION...MJ
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
600 PM CDT THU APR 2 2015 .UPDATE... ISSUED AT 600 PM CDT THU APR 2 2015 THE COLD FRONT IS NOW THROUGH THE FORECAST AREA...WITH WINDS NOW NW ACROSS THE REGION. MIXING DEPTH IS MORE SHALLOW ALONG WITH WEAKER WINDS ALOFT BEHIND THE FRONT. WILL ALLOW THE WIND ADVISORY TO EXPIRE AT 7PM...ALTHOUGH IT WILL REMAIN BREEZY FOR SEVERAL MORE HOURS. LATEST RADAR IMAGERY INDICATES NO MORE RETURNS AS THE FORCING HAS SUBSTANTIALLY WEAKENED...AND REMOVED ANY LINGERING POPS FOR THIS EVENING. ANTICIPATE CLEARING FRONT NORTH TO SOUTH THIS EVENING...AND MIN TEMPS IN THE TEENS OR LOWER 20S. WILL ALSO ALLOW THE RED FLAG WARNING TO EXPIRE AT 7PM SINCE WIND SPEEDS ARE DECREASING AND HUMIDITY VALUES INCREASING. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 320 PM CDT THU APR 2 2015 FORECAST CHALLENGE FOR REMAINDER OF TODAY WILL BE TRACKING A COLD FRONT FROM GRAND FORKS THROUGH THE REST OF THE CWA. WITHIN THE LAST 30 MIN...COLD FROPA OCCURRED AT THE NWS OFFICE. FRONT WAS PROCEED WITH A QUICK BURST OF LIGHT RAIN...A QUICK 15 DEG DROP ACCOMPANIED WITH SNOW PELLETS...THEN A TRANSITION TO SNOW FLAKES ALL WITHIN A 15 MIN PERIOD. THE FRONT IS NOW JUST SOUTH OF AND PARALLEL TO THE HWY 2 CORRIDOR...MOVING SOUTH. EXPECT THESE WX TRENDS TO CONTINUE OVER THE NEXT SEVERAL HOURS UNTIL THE FRONT DEPARTS THE CWA...WITH SOME LINGERING LIGHT SNOW BEHIND IT. FOR SIMPLICITY...HAVE PUT ALL SNOW IN FOR REMAINDER OF AFTN AS THAT IS THE PREDOMINANT P TYPE. RAP TEMPS BEST INDICATING NON DIURNAL TREND BUT TOO WARM...SO INITIATED TEMP BIAS TOOL WITH RAP AND RAN IT THROUGH 06Z. OVERNIGHT LOWS COULD REACH UPPER TEENS ALONG AND NORTH OF HWY 200. TONIGHT...TEMPS CONTINUE TO FALL BEHIND COLD FRONT AND PRECIP SHOULD BE OUT OF AREA BY 03Z...PERHAPS LINGERING A BIT LONGER IN THE FAR NORTHEAST. AS MENTIONED...OVERNIGHT LOWS WILL GENERALLY BE IN THE 20S AND PERHAPS UPPER TEENS IN THE NORTH AND EVEN LOW AROUND LAKES IN N CNTRL MN. TOMORROW AND TOMORROW NIGHT...SFC RIDGE MOVES INTO DVL REGION AROUND 12Z IN THE MORNING SLIDING INTO THE VALLEY AROUND NOONTIME. THIS WILL ALLOW SOME WESTERLY WINDS TO BRING A RETURN OF WARM AIR TO WESTERN ZONES...WITH MAX TEMPS RANGING FROM THE UPPER 40S WEST TO THE MID 30S EAST. NW FLOW ALOFT BRINGS ANOTHER WEAK VORT ACROSS THE REGION TOMORROW EVENING...WITH WEAK SFC CONVERGENCE GENERATING SOME LIGHT PRECIP IN THE EVENING HOURS INDICATED BY MOST MODELS. CONTINUED SOME LOW POPS ACROSS MAINLY THE NORTHERN HALF OF THE CWA. P TYPE SHOULD BE RAIN THROUGH MID EVENING WHEN A CHANGEOVER TO LIGHT SNOW FLAKES IS POSSIBLE AS SFC TEMPS FALL. NOTE BIS OFFICE HAS THUNDER ACROSS CNTRL DAKOTAS AS SOME WEAK INSTABILITY IS EXPECTED. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 320 PM CDT THU APR 2 2015 SATURDAY WILL BE DRY AND COOL ACROSS MOST OF THE CWA...WITH TEMPS INTO THE 50S ACROSS SOUTHEASTERN ND AND W CNTRL MN. SAT NIGHT...A BAND OF PRECIP MAY SET UP NORTH OF A WARM FRONTAL BOUNDARY ACROSS SD AND SW MN. HAVE CONTINUED SOME LOW POPS ACROSS THE CENTRAL CWA WITH MAIN ISSUE BEING P TYPE...DEPENDENT ON HOW MUCH WARM AIR ADVECTS NORTH. EASTERLY FLOW EVENTUALLY TURNS NORTHERLY AND KEEPS SAT NIGHT LOWS IN THE 20S...SO OVERNIGHT PRECIP WILL BE BACK TO SNOW ALBEIT LIGHT TO NO ACCUMULATIONS AS ASPHALT TEMPS ARE AROUND 35 DEG. LONG WAVE UPPER LEVEL TROUGH OVER EASTERN CANADA SHIFTS INTO THE NORTHEASTERN ATLANTIC. SPLIT FLOW DEVELOPS OVER THE WESTERN NORTH AMERICA BY DAY 5 AS LONG WAVE RIDGE BUILDS OVER WESTERN CANADA. SPLIT FLOW BEGINS TO SHIFT INTO CENTRAL NORTH AMERICA BY THE END OF THE PERIOD. THE ECMWF IS A LITTLE FASTER SOLUTION THAN THE GFS. WILL BLEND THE GFS AND ECMWF. POPS TRIMMED BACK IN THE SOUTHERN ZONES FOR WED NIGHT. LITTLE CHANGE TO HIGH TEMPS FOR MON AND TUE. HIGH TEMPS GENERALLY DECREASED ONE OR TWO DEGREES FOR WED AND DECREASED ZERO TO THREE DEGREES FOR THU. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 600 PM CDT THU APR 2 2015 WINDS NOW NW AT ALL TAF SITES...AND WILL GRADUALLY DIMINISH THROUGH THE OVERNIGHT HOURS. COULD BE A BRIEF PERIOD OF MVFR CIGS EARLY THIS EVENING...OTHERWISE ANTICIPATE VFR CONDITIONS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...SPEICHER LONG TERM...HOPPES/SPEICHER AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
339 PM CDT THU APR 2 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 320 PM CDT THU APR 2 2015 FORECAST CHALLENGE FOR REMAINDER OF TODAY WILL BE TRACKING A COLD FRONT FROM GRAND FORKS THROUGH THE REST OF THE CWA. WITHIN THE LAST 30 MIN...COLD FROPA OCCURRED AT THE NWS OFFICE. FRONT WAS PROCEED WITH A QUICK BURST OF LIGHT RAIN...A QUICK 15 DEG DROP ACCOMPANIED WITH SNOW PELLETS...THEN A TRANSITION TO SNOW FLAKES ALL WITHIN A 15 MIN PERIOD. THE FRONT IS NOW JUST SOUTH OF AND PARALLEL TO THE HWY 2 CORRIDOR...MOVING SOUTH. EXPECT THESE WX TRENDS TO CONTINUE OVER THE NEXT SEVERAL HOURS UNTIL THE FRONT DEPARTS THE CWA...WITH SOME LINGERING LIGHT SNOW BEHIND IT. FOR SIMPLICITY...HAVE PUT ALL SNOW IN FOR REMAINDER OF AFTN AS THAT IS THE PREDOMINANT P TYPE. RUC TEMPS BEST INDICATING NON DIURNAL TREND BUT TOO WARM...SO INITIATED TEMP BIAS TOOL WITH RUC AND RAN IT THROUGH 06Z. OVERNIGHT LOWS COULD REACH UPPER TEENS ALONG AND NORTH OF HWY 200. TONIGHT...TEMPS CONTINUE TO FALL BEHIND COLD FRONT AND PRECIP SHOULD BE OUT OF AREA BY 03Z...PERHAPS LINGERING A BIT LONGER IN THE FAR NORTHEAST. AS MENTIONED...OVERNIGHT LOWS WILL GENERALLY BE IN THE 20S AND PERHAPS UPPER TEENS IN THE NORTH AND EVEN LOW AROUND LAKES IN N CNTRL MN. TOMORROW AND TOMORROW NIGHT...SFC RIDGE MOVES INTO DVL REGION AROUND 12Z IN THE MORNING SLIDING INTO THE VALLEY AROUND NOONTIME. THIS WILL ALLOW SOME WESTERLY WINDS TO BRING A RETURN OF WARM AIR TO WESTERN ZONES...WITH MAX TEMPS RANGING FROM THE UPPER 40S WEST TO THE MID 30S EAST. NW FLOW ALOFT BRINGS ANOTHER WEAK VORT ACROSS THE REGION TOMORROW EVENING...WITH WEAK SFC CONVERGENCE GENERATING SOME LIGHT PRECIP IN THE EVENING HOURS INDICATED BY MOST MODELS. CONTINUED SOME LOW POPS ACROSS MAINLY THE NORTHERN HALF OF THE CWA. P TYPE SHOULD BE RAIN THROUGH MID EVENING WHEN A CHANGEOVER TO LIGHT SNOW FLAKES IS POSSIBLE AS SFC TEMPS FALL. NOTE BIS OFFICE HAS THUNDER ACROSS CNTRL DAKOTAS AS SOME WEAK INSTABILITY IS EXPECTED. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 320 PM CDT THU APR 2 2015 SATURDAY WILL BE DRY AND COOL ACROSS MOST OF THE CWA...WITH TEMPS INTO THE 50S ACROSS SOUTHEASTERN ND AND W CNTRL MN. SAT NIGHT...A BAND OF PRECIP MAY SET UP NORTH OF A WARM FRONTAL BOUNDARY ACROSS SD AND SW MN. HAVE CONTINUED SOME LOW POPS ACROSS THE CENTRAL CWA WITH MAIN ISSUE BEING P TYPE...DEPENDENT ON HOW MUCH WARM AIR ADVECTS NORTH. EASTERLY FLOW EVENTUALLY TURNS NORTHERLY AND KEEPS SAT NIGHT LOWS IN THE 20S...SO OVERNIGHT PRECIP WILL BE BACK TO SNOW ALBEIT LIGHT TO NO ACCUMULATIONS AS ASPHALT TEMPS ARE AROUND 35 DEG. LONG WAVE UPPER LEVEL TROUGH OVER EASTERN CANADA SHIFTS INTO THE NORTHEASTERN ATLANTIC. SPLIT FLOW DEVELOPS OVER THE WESTERN NORTH AMERICA BY DAY 5 AS LONG WAVE RIDGE BUILDS OVER WESTERN CANADA. SPLIT FLOW BEGINS TO SHIFT INTO CENTRAL NORTH AMERICA BY THE END OF THE PERIOD. THE ECMWF IS A LITTLE FASTER SOLUTION THAN THE GFS. WILL BLEND THE GFS AND ECMWF. POPS TRIMMED BACK IN THE SOUTHERN ZONES FOR WED NIGHT. LITTLE CHANGE TO HIGH TEMPS FOR MON AND TUE. HIGH TEMPS GENERALLY DECREASED ONE OR TWO DEGREES FOR WED AND DECREASED ZERO TO THREE DEGREES FOR THU. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 102 PM CDT THU APR 2 2015 MVFR CONDITIONS WERE MOVING INTO THE NORTHWEST ZONES. ALSO SOME IFR CONDITIONS WERE OCCURRING WHERE PRECIP WAS MOVING INTO THE NORTHWESTERN ZONES. BRISK WEST WINDS WERE ACROSS MUCH OF THE AREA AND A COLD FRONT WAS MOVING INTO THE NORTHWEST ZONES AND WINDS WILL SHIFT TO MORE NORTHERLY POST FRONTAL. EXPECT FRONT TO MOVE THROUGH GFK AROUND 20Z TO 21Z AND FAR AROUND 22Z TO 23Z. LOW CLOUDS EXPECTED TO CLEAR LATER THIS EVENING. && .FIRE... ISSUED AT 320 PM CDT THU APR 02 2015 RED FLAG WARNINGS WILL REMAIN IN PLACE THROUGH 7 PM. A COLD FRONT MOVING SOUTHEAST THROUGH THE AREA WILL MAKE FOR LARGE CHANGES IN THE WEATHER CONDITIONS THRU THE LATE AFTERNOON. RELATIVE HUMIDITIES IN THE MID 20S OUT AHEAD OF THE FRONT IN FAR SOUTHEASTERN NORTH DAKOTA INTO WEST CENTRAL MINNESOTA WILL BE REPLACED BY GUSTY NORTHWEST WINDS TO 40 MPH BUT SOME LIGHT PRECIPITATION AND RECOVERING RELATIVE HUMIDITIES INTO THE 50 TO 60 PERCENT RANGE. SHIFTING WINDS WILL MAKE FOR HAZARDOUS CONDITIONS FOR ANY BURNS OR FIRES CURRENTLY IN PROGRESS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR NDZ038-039-049- 052-053. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ006-014-015-024- 026-028>030-038-039-049-052-053. MN...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR MNZ003-024- 027>032-040. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ002-003-022- 027>032-040. && $$ SHORT TERM...SPEICHER LONG TERM...HOPPES/SPEICHER AVIATION...HOPPES FIRE...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
102 PM CDT THU APR 2 2015 .UPDATE... ISSUED AT 102 PM CDT THU APR 2 2015 LATEST METARS INDICATING WIND GUSTS IN THE 40 TO 50 MPH RANGE ALONG THE I 94 CORRIDOR WHILE THE COLD FRONT IS DROPPING INTO THE NORTHERN TIER OF COUNTIES ALONG THE INTL BORDER...RESULTING IN AN ABRUPT WIND SHIFT TO THE NORTH. WHILE UPSTREAM WINDS NEAR WINNIPEG ARE IN CRITERIA...THOSE HIGHER WINDS ARE COMING OFF OF THE LAKES AND WINDS TO THE SOUTH ARE UNDER CRITERIA. THINKING THE NORTHERLY WINDS WILL REMAIN BELOW CRITERIA AND WILL KEEP WIND ADVISORY AS IS. ALL PRECIP IS ALONG AND BEHIND THE FRONT AND WITH RAPIDLY DROPPING TEMPS...ALL REPORTS HAVE BEEN SNOW. THIS WILL BE SHORT LIVED WITH NO ACCUMULATION AS TEMPS HAD RISEN INTO THE MID 40S...EXPECT THE SNOW TO MELT ON CONTACT DESPITE REPORTS OF BLOWING SNOW REDUCING VSBYS FOR VERY BRIEF PERIODS OF TIME. ONLY CHANGE TO FCST IS TO CHANGE P TYPE IN MN TO ALL SNOW AFT 21Z...AND ALL SNOW IN ND EFFECTIVE THIS UPDATE. UPDATE ISSUED AT 1039 AM CDT THU APR 2 2015 FORECAST CHALLENGE FOR TODAY WILL BE WINDS AND SOME LIGHT PRECIP ACROSS THE NORTH. WIND SHIFT ASSOCIATED WITH FRONTAL BOUNDARY DROPPING IN FROM CANADA IS JUST NORTH OF THE BORDER...BETWEEN WINNIPEG AND THE INTL BORDER. WINDS ACROSS NORTH DAKOTA GENERALLY FROM THE WEST AND INTO ADVISORY CRITERIA ACROSS CNTRL ND. STRONGER WINDS SHOULD GET INTO WESTERN ZONES BY NOONTIME...AND ONLY IMPACT NORTHWEST ZONES FOR A SHORT PERIOD BEFORE SHIFTING TO THE NW. WESTERLY WINDS WILL CONTINUE ALONG AND SOUTH OF HWY 200 FOR MUCH OF THE AFTN...WITH THE BEST MIXING AND STRONGEST WINDS ACROSS THE FAR SOUTHERN ZONES MID AFTN. HAVE ISSUED A WIND ADVISORY FROM NOONTIME TO 7 PM CDT. ALSO MADE SIGNIFICANT CHANGES TO POPS AS CURRENT ECHOES WEST OF THE CWA AND MOST OF CWA IS CLEAR...WITH CLOUDS NOW INCREASING OVER NORTHEAST ND. USED RUC AS GUIDANCE AND DELAYED ONSET OF PRECIP. UPDATE ISSUED AT 657 AM CDT THU APR 2 2015 MAIN CHALLENGE REMAINS WINDS AND TEMPS. STILL EXPECT WINDS TO INCREASE WITH INVERSION BREAK AROUND 15Z AND ARE REFLECTED IN THE FCST. ALSO EXPECTING WINDS TO HOVER NEAR ADVISORY CRITERIA IN THE SW ZONES...BUT WILL HOLD OFF ON ANY HEADLINES FOR NOW. TEMPS SO FAR LOOKING OKAY SO WILL NOT MAKE ANY ADJUSTMENTS ATTM. REST OF FORECAST ON TARGET. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 358 AM CDT THU APR 2 2015 MAIN CHALLENGE WILL BE WINDS AND TEMPS FOR TODAY. UPPER TROF WILL PUSH ACROSS THE AREA TODAY...AND ASSOCIATED SFC SYSTEM WILL BRING COOLER AIR ALONG WITH A CHANCE FOR SHOWERS. WINDS WILL INCREASE IN TIGHTENING GRADIENT...AND MODEL SOUNDINGS INDICATE AN ADIABATIC LAYER. UNIDIRECTIONAL WINDS ARE ALSO SHOWN THRU AROUND 850MB TO ALLOW MIXING OF 35-40 KTS DOWN TO THE SFC. STRONGEST WINDS WILL BE IN THE FAR SRN ZONES...BUT MARGINALLY CLOSE TO ADVISORY CRITERIA FOR ONLY A FEW HOURS SO WILL HOLD ON ANY WIND HEADLINES FOR NOW. COOL AND DRY WEATHER IS IN STORE FOR FRIDAY AS CANADIAN SFC HIGH PRESSURE MOVES OVER THE FA. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 358 AM CDT THU APR 2 2015 FOR FRIDAY NIGHT INTO SATURDAY NIGHT...UPPER PATTERN SHOWS MORE OF A NW FLOW REGIME WITH ANOTHER WAVE FCST TO CROSS THE AREA...BRINGING ANOTHER CHANCE FOR LIGHT PCPN. OTHERWISE...EXPECT MAINLY COOL CONDITIONS TO PERSIST. SUNDAY THROUGH WEDNESDAY...FLOW PATTERN BEGINS TO SHIFT WITH SOME MORE SIGNIFICANT TROUGHS DIGGING INTO THE WESTERN CONUS AND THEN COMING OUT INTO THE PLAINS. ONE SUCH SYSTEM WILL BRING WEST TO SOUTHWESTERLY FLOW ALOFT ACROSS THE NORTHERN PLAINS FOR SUNDAY...AND THE ECMWF BREAKS OUT SOME PRECIP WITH A LEAD SHORTWAVE. THINK THAT MUCH OF THE ACTIVITY WILL HOLD OFF UNTIL MONDAY WHEN THE SYSTEM PROGRESSES INTO THE NORTHERN ROCKIES. THE GEM TRACKS A STRONG SFC LOW JUST TO OUR SOUTH AND DUMPS OVER A FOOT OF SNOW ALL THE WAY NORTH OF FARGO...BUT THE OTHER DETERMINISTIC MODELS ARE WEAKER AND FURTHER SOUTH WITH THEIR MAIN DEFORMATION BAND. WILL CONTINUE TO KEEP POPS HIGH WITH A MIX OF RAIN AND SNOW FOR NOW AND WILL KEEP A CLOSE EYE ON THE SYSTEM AS IT DRAWS CLOSER. COLD SFC HIGH PRESSURE WILL BUILD DOWN INTO THE AREA FOR TUESDAY AND WEDNESDAY...AND THINK WE SHOULD DRY OUT BY THAT POINT BUT TEMPS WILL REMAIN BELOW SEASONAL AVERAGES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 102 PM CDT THU APR 2 2015 MVFR CONDITIONS WERE MOVING INTO THE NORTHWEST ZONES. ALSO SOME IFR CONDITIONS WERE OCCURRING WHERE PRECIP WAS MOVING INTO THE NORTHWESTERN ZONES. BRISK WEST WINDS WERE ACROSS MUCH OF THE AREA AND A COLD FRONT WAS MOVING INTO THE NORTHWEST ZONES AND WINDS WILL SHIFT TO MORE NORTHERLY POST FRONTAL. EXPECT FRONT TO MOVE THROUGH GFK AROUND 20Z TO 21Z AND FAR AROUND 22Z TO 23Z. LOW CLOUDS EXPECTED TO CLEAR LATER THIS EVENING. && .FIRE WEATHER... ISSUED AT 358 AM CDT THU APR 02 2015 TEMPS WILL BE MUCH COOLER THAN YESTERDAY...BUT WITH DEW POINTS IN THE 20S AFTERNOON RELATIVE HUMIDITY VALUES WILL GET DOWN INTO THE 20 TO 35 PERCENT RANGE IN OUR SOUTHERN COUNTIES. PORTIONS OF WEST CENTRAL MINNESOTA ARE EXPECTED TO BE THE DRIEST AND DROP BELOW 25 PERCENT...BUT THE STRONGEST WINDS WILL BE IN SOUTHEASTERN NORTH DAKOTA. WITH THE WINDS OVER 30 MPH AND WITH VERY DRY FUELS...FIRES COULD SEE EXPLOSIVE GROWTH EVEN WITH RH VALUES IN THE BORDERLINE CATEGORY. THUS...WILL INCLUDE A RED FLAG WARNING FOR ALL OF THE SOUTHERN COUNTIES. IF THE COLD FRONT COMES IN A BIT FASTER THAN EXPECTED THERE COULD BE SOME RH RECOVERY...BUT FOR NOW IT SEEMS THAT THE AFTERNOON WILL BE VERY DRY AND WINDY SO WILL GO WITH THE RED FLAG AND LATER SHIFTS CAN CANCEL EARLY IF NEEDED. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR NDZ038-039-049- 052-053. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ006-014-015-024- 026-028>030-038-039-049-052-053. MN...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR MNZ003-024- 027>032-040. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ002-003-022- 027>032-040. && $$ UPDATE...SPEICHER SHORT TERM...HOPKINS LONG TERM...HOPKINS/JR AVIATION...HOPPES FIRE WEATHER...JR
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
647 PM EDT THU APR 2 2015 .SYNOPSIS... A COLD FRONT WILL DROP SOUTH INTO THE OHIO VALLEY AND REMAIN ACROSS THE AREA THROUGH FRIDAY. SEVERAL WAVES OF LOW PRESSURE TRAVELING ALONG THE FRONT WILL PROVIDE MULTIPLE ROUNDS OF STORMS. HIGH PRESSURE AND DRIER AIR WILL MOVE BACK IN FOR SATURDAY INTO SUNDAY. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... INITIAL AXIS OF STORMS MOVING THRU ILN/S SRN FA. IN WAKE OF THIS AXIS OF STORMS SEVERE THREAT HAS AT LEAST TEMPORARILY DIMINISHED. HAVE UPDATED TO CANCEL THE SEVERE THUNDERSTORM WATCH. ADDITIONAL STORMS DEVELOPING ACRS SRN INDIANA WHERE BLYR CAPES AROUND 1000 J/KG. LATEST HRRR OUTPUT APPEARS TO HAVE A GOOD HANDLE ON CURRENT CONVECTIVE TRENDS. EXPECT THESE STORMS TO PUSH INTO ILN/S SW CWA AND THEN WEAKEN SOME AS THEY MOVE AWAY FROM GENESIS REGION. QUESTION REVOLVES AROUND POTENTIAL FOR ADDITIONAL SVR CHANCES. CAN NOT RULE OUT PSBL ISOLD SVR OVER OUR SW COUNTIES BUT THIS WINDOW DIMINISHES BY LATE EVENING WITH INSTBY BEING THE LIMITING FACTOR. EVENTUALLY OVERNIGHT...STILL LOOKS GOOD FOR HEAVY RAIN POSSIBLE FLOOD SIGNAL ACRS OUR SRN COUNTIES. PREVIOUS DISCUSSION... BROAD MOIST SOUTHWESTERLY MID LEVEL FLOW WITH SLOW MOVING COLD FRONT DROPPING INTO OHIO OVERNIGHT. MARGINAL INSTBY HAS DEVELOPED INTO SW OHIO. STORMS OVER THE LOWER OHIO VALLEY ARE DEVELOPING INTO A LINE. WIND FIELDS AND WET BULB ZERO HEIGHTS SUGGEST THAT SOME OF THE STRONGER UPDRAFTS WILL BE CAPABLE OF PRODUCING LARGE HAIL AND DAMAGING WINDS EARLY THIS EVENING. CONVECTIVE ENABLING MODELS SHOW SUGGEST THAT THIS COLD POOL DRIVEN CONVECTION DEVELOPS INTO ILN/S SW FA IN RGN OF FAVORABLE LOW LEVEL CONVERGENCE INTO THIS EVENING. EXPECT ADDITIONAL STORMS TO COME TOGETHER AHEAD OF THE SFC COLD FRONT BETWEEN 06Z AND 12Z IN NEXT REGION OF FAVORABLE LOW LEVEL CONVERGENCE. IN FAVORABLE MOISTURE TRANSPORT PW/S TO INCREASE TO AROUND 250 PERCENT OF NORMAL OR 2 TO 3 STD DEVIATIONS ABOVE NORMAL. DUE TO PROLONGED PERIOD OF PCPN AND VERY MOIST ENVIRONMENT...EXPECT 1 TO 3+ INCHES OF RAINFALL THRU FRIDAY. WILL CONTINUE FLOOD WATCH TONIGHT INTO FRIDAY. GOOD GRADIENT TO TEMPERATURES WITH FRONT BISECTING THE AREA. LOWS FROM THE MID/UPR 40S NW TO UPPER 50S SE. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/... BROAD SOUTHWESTERLY MID LEVEL FLOW WITH SLOW MOVING FRONT DROPPING SOUTH THRU ILN/S FA FRIDAY WITH H5 TROF SETTLING INTO GREAT LAKES/OH VLY FRIDAY NIGHT. VERY MOIST ENVIRONMENT TO CONTINUE ACROSS THE SOUTH WITH PW/S IN EXCESS OF 200 PERCENT OF NORMAL. AXIS OF FAVORABLE LOW LEVEL FORCING TO BECOME ENHANCED WITH 8H TROF DROPPING THRU FA FRIDAY AFTN/FRIDAY EVENING. SIGNIFICANT SFC WAVE TO RIPPLE NE THRU THE FA FRIDAY EVENING. FRONT/SFC LOW BISECTING FA WILL LEAD TO GOOD TEMPERATURES GRADIENT WITH FRIDAYS HIGHS RANGING FROM MID 50S NW TO THE UPPER 60S SE. DEEP MOISTURE AND LIFT TO PIVOT EAST OF ILN/S FRIDAY NIGHT. THERE MAY BE A VERY BRIEF PERIOD OF RAIN/SNOW MIX PRIOR TO ENDING AS COLDER AIR IS FUNNELED IN. ANY SNOW WILL BE MINIMAL AND ONLY HAVE UP TO A TENTH OF AN INCH OVER EXTREME NE. LOWS FRIDAY NIGHT TO RANGE FROM NEAR 30 NW TO THE UPPER 30S SE. NW FLOW ALOFT WITH SFC HIGH PRESSURE BUILDING IN SATURDAY. EXPECT DECREASE IN CLOUDS WITH A GOOD DEAL OF SUNSHINE SATURDAY. ALTHOUGH SKIES WILL BE MOSTLY SUNNY...TEMPERATURES WILL BE 5 TO 10 DEGREES BELOW NORMAL WITH HIGHS RANGING FROM THE UPPER 40S NW TO THE LOWER 50S SE. THIS SFC HIGH TO BUILD ACRS THE AREA SAT NIGHT WITH MOSTLY CLEAR SKY CONDITIONS AND LIGHT WINDS. LOWS TO RANGE FROM THE LOWER 30S EAST TO THE MID/UPR 30S WEST. && .LONG TERM /SUNDAY THROUGH THURSDAY/... DRY WEATHER IS EXPECTED SUNDAY AS HIGH PRESSURE MOVES EAST. FOR MONDAY THROUGH THURSDAY...THE ACTIVE PATTERN WILL RETURN. A FRONTAL BOUNDARY CONTAINING ABUNDANT MOISTURE WILL DEVELOP MONDAY NEAR THE WESTERN GREAT LAKES. MODELS ARE IN GOOD AGREEMENT THAT THE FRONT WILL FORM...BUT THE LOCATION...TIMING AND DURATION OF PRECIPITATION IS IN QUESTION. A FEW SHOWERS MAY OCCUR MONDAY IN MOISTURE ADVECTION AND SHORT WAVE ENERGY SOUTH OF THE BOUNDARY. SHOWERS AND THUNDERSTORMS WILL BECOME LIKELY ON TUESDAY WHEN THE FRONT IS FORECAST TO SAG SOUTH TOWARD OHIO. THERE WILL BE A GOOD CHANCE FOR SHOWERS WEDNESDAY AND THURSDAY IN THE PERSISTENTLY MOIST REGIME ASSOCIATED WITH THE UNDULATING FRONT. TEMPERATURES WILL START OUT NEAR NORMAL SUNDAY WITH HIGHS IN THE LOWERS 60S. IT MAY BE A COUPLE DEGREES COOLER MONDAY UNDER WEAK COLD ADVECTION. TUESDAY IS SHAPING UP TO BE THE WARMEST DAY IN THIS PERIOD WHEN WARM ADVECTION MAY BOOST READINGS TO AROUND 70. A RETURN TO NEAR NORMAL LOWER 60S APPEARS TO BE IN STORE FOR WEDNESDAY AND THURSDAY IN AN ENVIRONMENT OF LIMITED SUNSHINE AND COLD ADVECTION. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... A COMPLEX WEATHER SITUATION CAN BE EXPECTED ACROSS THE REGION TODAY THROUGH FRIDAY NIGHT. FOR THIS AFTERNOON INTO THIS EVENING...THE TIMING OF SHOWERS AND THUNDERSTORMS WILL BE SOMEWHAT DIFFICULT GIVEN THAT HIGH RESOLUTION MODELS ARE DOING A POOR JOB GIVEN CURRENT RADAR MOSAIC AND THEREFORE THE TIMING OF FUTURE CONVECTION AND WHEN IT WILL MOVE ACROSS THE TAF STIES HAS SOME UNCERTAINTY. WARM...MOIST AIR CONTINUES TO FUNNEL NORTHEAST INTO THE REGION AHEAD OF AN ADVANCING COLD FRONT. THIS MOISTURE IS CURRENTLY INTERACTING WITH AN EMBEDDED DISTURBANCE WHICH IS PRODUCING SHOWERS AND A FEW THUNDERSTORMS. THE POTENTIAL FOR MORE ROBUST SHOWERS AND THUNDERSTORMS SHOULD COME LATE THIS AFTERNOON INTO THIS EVENING WHEN GREAT INSTABILITY AND PREFRONTAL CONVERGENCE DEVELOPS ALONG AND AHEAD OF FRONT...WITH PRECIPITATION LIKELY PROPAGATING AWAY FROM THE FRONTAL BOUNDARY. HAVE PLACED TEMPO TSRA IN ALL TAF SITES WITH SOME MVFR CEILINGS/LOCAL IFR VISIBILITIES POSSIBLE. FOR THE OVERNIGHT PERIOD...FRONTAL BOUNDARY WILL SAG SOUTHEAST AND SHOULD STALL NEAR THE OHIO RIVER. A LOW LEVEL JET IN ASSOCIATION WITH ANOTHER DISTURBANCE ALOFT WILL PRODUCE MORE SHOWERS...AND PERHAPS A FEW THUNDERSTORMS...MAINLY ALONG AND SOUTH OF THE OHIO RIVER. MODERATE TO LOCALLY HEAVY RAIN WILL BE POSSIBLE. A SATURATED AIRMASS AND NIGHT TIME COOLING WILL LIKELY ALLOW CEILINGS TO DROP INTO THE IFR CATEGORY. FOR FRIDAY...MORE DIGGING ENERGY FROM THE NORTHWEST WILL PERTURB A WAVE OF LOW PRESSURE ALONG STALLED BOUNDARY WHICH WILL MOVE NORTHEAST ACROSS THE OHIO RIVER VALLEY. SHOWERS AND PERHAPS A FEW THUNDERSTORMS CAN BE EXPECTED. MODERATE TO LOCALLY HEAVY RAIN WILL CONTINUE TO BE A THREAT...ESPECIALLY ALONG AND SOUTH OF THE OHIO RIVER. IFR CEILINGS IN THE MORNING SHOULD LIFT TO MVFR. VISIBILITIES WILL RANGE BETWEEN MVFR AND IFR IN MODERATE TO LOCALLY HEAVY RAIN. OUTLOOK...MVFR AND POSSIBLY IFR CEILINGS AND VISIBILITIES CONTINUING INTO FRIDAY NIGHT. MVFR CEILINGS AND VISIBILITIES POSSIBLE MONDAY INTO TUESDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...FLOOD WATCH THROUGH FRIDAY EVENING FOR OHZ070>073-077>082-088. KY...FLOOD WATCH THROUGH FRIDAY EVENING FOR KYZ089>100. IN...FLOOD WATCH THROUGH FRIDAY EVENING FOR INZ066-073>075-080. && $$ SYNOPSIS...AR NEAR TERM...AR SHORT TERM...AR LONG TERM...CONIGLIO AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
203 PM EDT THU APR 2 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE EAST ACROSS ONTARIO TODAY AND DRAG A WARM FRONT ACROSS OHIO AND THE LOWER GREAT LAKES REGION. A COLD FRONT WILL FOLLOW MOVING THROUGH FROM THE NORTHWEST DURING THE EVENING. THE COLD FRONT WILL STALL ACROSS SOUTHERN OHIO FRIDAY AS LOW PRESSURE MOVES NORTHEAST ALONG THE BOUNDARY. HIGH PRESSURE WILL TRY TO BUILD OVER THE REGION FROM THE SOUTH THIS WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MADE SOME CHANGES TO ACCOUNT FOR THE LINE OF SHOWERS MOVING ACROSS THE AREA. SOME EMBEDDED THUNDER BEING REPORTED AS WELL. BEHIND THIS LINE THERE WILL BE A SEVERAL HOUR PERIOD OF MAINLY DRY WEATHER AND HAVE TRIED TO ACCOUNT FOR THAT AS WELL. THIS CONVECTION APPEARS TO BE ELEVATED AND ASSOCIATED WITH A WARM FRONT ALOFT AS SURFACE DEWPOINTS REMAIN VERY LOW. NOT SURE HOW FAR EAST IT WILL GET BEFORE THE DRY AIR WINS OUT. HAVE RAMPED UP WINDS SOME FOR THIS AFTERNOON...ESPECIALLY IN NW OHIO. LOCAL SCHEMES SUGGEST GUSTS COULD GET CLOSE TO ADVISORY CRITERIA. WILL GO WITH 40 MPH FOR NOW AND CONTINUE TO MONITOR. CLOUDS INCREASING FROM THE WEST AND NORTHWEST OVERNIGHT AHEAD OF APPROACHING SYSTEM HOWEVER CLOUDS AT THIS POINT REMAIN FAIRLY THIN AND ANY PRECIP WELL WEST OF THE AREA. BY 12Z THE HRRR HAS SHOWERS INTO THE WESTERN COUNTIES. SREF ALSO HAD PRECIP NEAR THE AREA AT 12Z WHILE THE NAM PRINTS OUT A SWATH OF CAPE ON OUR WESTERN BORDER. GIVEN THIS WILL BEGIN WITH CHANCE POPS IN THE WEST AT 12Z. BY 15Z DECENT MOISTURE REACHES AS FAR EAST AS CLEVELAND. FURTHER SATURATION OCCURS EAST IN THE AFTERNOON. WILL HAVE POPS INCREASE TO LIKELY IN THE WEST THROUGH THE MID/LATE MORNING WITH CATEGORICAL POPS WEST EARLY AFTERNOON...SWEEPING EAST-SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING. ALSO...WILL HAVE THUNDER BEGIN AT NOON. MAIN CONCERN WILL BE POTENTIAL FOR SEVERE WITH DEEP MOISTURE AND AFTERNOON HEATING COMBINE WITH INCREASING LOW LEVEL SHEAR. AT THIS TIME WESTERN COUNTIES IN A MARGINAL OUTLOOK WITH BEST CHANCES SOUTHWEST OF THE AREA. HIGHS WELL INTO THE 60S WITH 70 NOT OUT OF THE QUESTION. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... TONIGHT BEGINS WITH WHAT WILL LIKELY BE A LINE OF CONVECTION IN OR MOVING INTO WESTERN OHIO WHICH WILL MOVE SLOWLY EAST-SOUTHEAST THROUGH THE NIGHT. WILL HAVE CAT POPS AND WILL CONTINUE WITH THUNDER THROUGH THE EVENING BUT DROP IT FOR THE OVERNIGHT AS INSTABILITY DECREASES. BY FRIDAY MORNING THE FRONT SHOULD BE IN SOUTHERN OHIO WITH A BRIEF PERIOD OF WEAK HIGH PRESSURE AND DRIER AIR BUILDING IN FROM THE NORTH. BY FRIDAY EVENING HOWEVER...MODELS SHOW LOW PRESSURE MOVES ALONG THE FRONT IN SOUTHERN OHIO SPREADING MOISTURE AND INSTABILITY BACK INTO THE AREA FROM THE SOUTH. WILL BEGIN WITH ONLY A SLIGHT CHANCE POPS SOUTH BUT INCREASE TO CHANCE THROUGH THE MORNING. BY AFTERNOON BROUGHT CATEGORICAL POPS BACK TO A LARGE PORTION OF THE AREA. RAIN CONTINUES INTO THE NIGHT AND THE TRICKY BIT IS THAT COLD ADVECTION BEHIND THE LOW WILL LIKELY TURN PRECIP OVER TO SNOW AFTER MIDNIGHT. THIS WILL BE A CLASSIC ISSUE OF HOW LONG WILL SNOW OCCUR BEFORE THE PRECIP ENDS. MODELS HAVE SHOW SOME CONSISTENCY PAST COUPLE NIGHT WITH SNOW AFTER MIDNIGHT WITH A COUPLE INCHES POSSIBLE BY MORNING. THE MOST SHOULD BE IN THE ELEVATED AREAS OF NWRN PA WHERE 4 INCHES COULD FALL. DONT EXPECT WARNING AMOUNTS BUT COULD POSSIBLY END UP NEEDING AN ADVISORY. PRECIP SHOULD END BY 12Z SATURDAY MOST PLACES AND WILL CONTINUE INTO SAT MORNING ONLY FOR NWRN PA AND XTRM NERN OHIO. SAT MID MORNING AND AFTERNOON SHOULD BE DRY AS HIGH PRESSURE BUILDS IN. NEXT CHANCE OF PRECIP COMES LATE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT BACK DOORS INTO THE AREA. NOT A LOT OF FORCING SO WILL HAVE ONLY CHANCE/SLIGHT CHANCE POPS. SUNDAY NIGHT HOWEVER THE GFS IS SHOWING THAT THE GLFMX MOISTURE GETS TAPPED...REACHING INTO THE AFTER AFTER MIDNIGHT SO WILL HAVE CHANCE POPS FOR ALL. CHILLY SATURDAY BEHIND THE FRONT BUT OTHERWISE NEAR TO ABOVE NORMAL TEMPS. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... A WARMER AND WET PATTERN SETTING UP FOR THE EXTENDED. MODELS CONTINUE WITH A NEARLY STATIONARY FRONT ACROSS THE AREA ON MONDAY. THEN LOW PRESSURE SYSTEM MOVES ALONG STATIONARY FRONT TUESDAY. ECMWF TRACK AND TIMING FASTER THAN LATEST GFS. FRONT SAGS SOUTH OF AREA AS A COLD FRONT WEDNESDAY...BUT THEN A SECOND LOW MOVES NE ALONG THE BOUNDARY THURSDAY. AGAIN PRECISE TIMING STILL IN DOUBT SO WILL CONTINUE WITH HIGH CHANCE POPS AFTER TUESDAY. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... NUMEROUS ROUNDS OF SHOWERS WILL MOVE ACROSS THE AREA THROUGH EARLY EVENING AHEAD OF AN APPROACHING COLD FRONT. A FEW EMBEDDED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON...BUT BEST CHANCES FOR THUNDERSTORMS WILL BE WITH THE LAST BAND ACCOMPANYING THE FRONT REACHING THE TOLEDO AREA BY 22Z AND ERI TOWARDS 00Z. CONDITIONS THIS AFTERNOON WILL GENERALLY BE VFR OUTSIDE OF SHOWERS...WITH VISIBILITIES BRIEFLY DROPPING AS LOW AS IFR. BREEZY SOUTHWEST WINDS WILL GUST AS HIGH AS 25-30 KNOTS AHEAD OF THE FRONT AND SHIFT TO WEST NORTHWEST TONIGHT. CEILINGS WILL LOWER TO LOW MVFR OR IFR BEHIND THE FRONT THIS EVENING BUT IMPROVE TO VFR AGAIN LATER TONIGHT AS HIGH PRESSURE BUILD IN. .OUTLOOK...NON-VFR RETURNING FRIDAY AND CONTINUING INTO EARLY SATURDAY. NON VFR RETURNING MONDAY. && .MARINE... WINDS WILL PICK UP FROM THE SOUTH TO SOUTHWEST ACROSS THE LAKE TODAY AS WARM FRONT LIFTS NE ACROSS THE LAKE. WINDS TURN TO THE NORTHWEST TONIGHT AND DIMINISH FAIRLY QUICKLY AS COLD FRONT PUSHES ACROSS THE LAKE. NORTHWEST FLOW INCREASES FRIDAY NIGHT AS LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY. WINDS AGAIN DIMINISH SATURDAY NIGHT INTO SUNDAY AS HIGH PRESSURE MOVES ACROSS THE LAKE. LIGHT AND VARIABLE FLOW IS EXPECTED UNDER THE INFLUENCE OF THE HIGH AND THEN STATIONARY FRONT THROUGH MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK/KUBINA SHORT TERM...TK LONG TERM...DJB AVIATION...KEC MARINE...DJB
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
457 PM EDT THU APR 2 2015 .SYNOPSIS... SCATTERED SHOWERS AND THUNDERSTORMS WILL COME TO AN END OVERNIGHT...BUT RETURN AGAIN AS A COLD FRONT WILL MOVES THROUGH NORTHEAST GEORGIA AND THE WESTERN CAROLINAS FRIDAY NIGHT. DRY HIGH PRESSURE MOVES IN FOR THE WEEKEND. MOISTURE WILL RETURN FOR THE START OF THE NEXT WORK WEEK AS SOUTHERLY FLOW DEVELOPS AND PRECIPITATION CHANCES INCREASE THROUGH THE WEEK. && .NEAR TERM /THROUGH FRIDAY/... AS OF 430 PM EDT...THE LATEST RUNS OF THE HRRR HAVE LATCHED ONTO THE ONGOING CONVECTION ACROSS THE CENTRAL UPSTATE AND SRN TIER OF NC...AS WELL AS THE CONVECTIVE FEATURES NEAR THE AL/GA BORDER. THE FIRST ROUND OF ACTIVITY WILL LIKELY SLIDE EAST THROUGH THE INTERSTATE 77 CORRIDOR THROUGH EARLY EVENING...TAKING ADVANTAGE OF ENCROACHING SFC BASED INSTABILITY FARTHER E AND SE. THE SECOND ROUND ASSOCIATED WITH A PASSING UPPER WAVE MAY TRANSIT THE SRN TIER OF THE FORECAST AREA THROUGH THE EVENING HOURS...AND POPS HAVE BEEN ADJUSTED TO FOCUS ON THESE TWO ROUNDS. OTHERWISE...INSITU DAMMING REMAINS FAIRLY PERSISTENT OVER FOOTHILLS SECTIONS...BUT WITH ELEVATED INSTABILITY ABOVE THE CAD. LOCALIZED HEAVY RAIN AND OCCASIONAL CLOUD TO GROUND STRIKES APPEARS THE MAIN ISSUE WITH ANY TSRA THIS EVENING. IN THE WAKE OF THE SHORTWAVE...SHOULD SEE A PERIOD OF CLEARING DURING THE DAY TOMORROW WITH INCREASING SOUTHERLY FLOW ALLOWING TEMPERATURES TO RISE WELL ABOVE SEASONAL NORMALS AND QUITE THE DIFFERENCE FROM THOSE TODAY. WOULD NOT BE SURPRISED TO SEE OFF AND ON SHOWER ACTIVITY IN THE MOUNTAINS WITH THE STRONG UPSLOPE FLOW SO HAVE KEPT SLIGHT TO LOW CHANCE POPS ACROSS NORTHERN AND WESTERN ZONES DURING THE DAY. LOW LEVEL LAPSE RATES INCREASE AND WILL HAVE TO WATCH WIND GUST POTENTIAL DURING AFTERNOON MIXING ESPECIALLY AT HIGHER ELEVATIONS. LATE FRIDAY WE START TO SEE THE INFLUENCE OF THE NEXT FRONT THAT WE HAVE BEEN ADVERTISING FOR SEVERAL DAYS NOW... WITH SLIGHT TO LOW CHANCE POPS CREEPING BACK INTO THE MOUNTAIN ZONES LATE IN THE NEAR-TERM PERIOD. BIGGEST CONCERN WITH THE FRONT REMAINS AFTER 00Z FRIDAY INTO THE SHORT TERM PORTION OF THE FORECAST. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... AS OF 215 PM THURSDAY...A BAND OF FRONTAL PRECIP IS EXPECTED TO BE KNOCKING ON THE DOOR OF THE CWFA AROUND 00Z SAT...BUT THE HIGH RES MODELS AND THE NAM/CMC/GFS ALL HAVE SLIGHT DIFFERENCES IN EXACT TIMING. THE ATMOSPHERE UPSTREAM SHUD BE UNSTABLE ENUF WITH PLENTY OF BULK SHEAR TO SUPPORT ORGANIZED STRONG TO SEVERE STORMS ACRS THE TN AND OH VALLEYS. HOWEVER...BY THE TIME THE CONVECTION REACHES THE TN/NC BORDER...INSTBY WILL BE MUCH MORE LIMITED...AND OVERALL WEAKENING IS EXPECTED. A COUPLE OF THE CONVECTION ALLOWING MODELS KEEP A LINE OF STORMS RIGHT UP TO THE NC BORDER. SO A MARGINAL THREAT FOR MAINLY DAMAGING WIND GUSTS...BUT ALSO PERHAPS LARGE HAIL WILL EXIST FRIDAY EVENING IN THE NC MTNS. THE REST OF THE CWFA WILL LIKELY STILL BE RELATIVELY CAPPED...SO LITTLE PRE-FRONTAL DISCRETE CONVECTION IS NOT EXPECTED. THE AMOUNT OF INSTBY IS ALMOST NIL BY 06Z SAT AS THE BAND OF PRECIP IS EXPECTED TO TRY TO ENTER THE PIEDMONT. ALSO...THE 1000-850 MB CONVERGENCE IS WEAK WITH THE FRONT AT THIS POINT. SO AM KEEPING THE 40-60% POP FOR THE EXPECTED AMOUNT OF SHOWER AND POSSIBLE TSTM COVERAGE EAST OF THE MTNS. QPF WILL BE GENERALLY A TENTH OF AN INCH OR LESS OUTSIDE THE MTNS...AND A TENTH TO QUARTER INCH IN THE MTNS. THE WEST-FACING SLOPES OF THE SMOKY MTNS MAY GET A HALF INCH OR MORE. TEMPS WILL BE ELEVATED WITHIN THE FRONTAL ZONE OVERNIGHT...BUT CAA WILL RAMP UP ALONG THE TN LINE TO BRING TEMPS INTO THE 30S WITH A FEW SNOW FLAKES POSSIBLE ABOVE ABOUT 5000 FT. LITTLE OR NO ACCUM EXPECTED. FROM SATURDAY THRU SUNDAY...CONDITIONS SHUD DRY OUT...AS CONTINENTAL HIGH PRES BUILDS IN FROM THE NW. TEMPS ARE EXPECTED TO WARM INTO THE 50S IN THE MTNS AND 60S ACRS THE PIEDMONT BOTH SATURDAY AND SUNDAY. THERE WILL BE SOME LINGERING WIND GUST POTENTIAL ON SATURDAY...AS NWLY CAA FLOW CONTINUES...ESP IN THE MTNS. THIS ON TOP OF LOW RH MAY ELEVATE FIRE WX CONCERNS...ESP IF THE CURRENT QPF IS OVERDONE. SATURDAY NIGHT SHUD BE CHILLY...AS THE CENTER OF HIGH PRES SETTLES INTO THE REGION...RESULTING IN NEARLY IDEAL RADIATIONAL COOLING CONDITIONS. THE LATEST CONSENSUS IS FOR 20S TO MID 30S FOR MOST OF NC...AND MID-UPR 30S ACRS NE GA AND THE UPSTATE. SO EXPECT SOME FREEZING TEMPS...ESP IN THE MTN VALLEYS...AND PATCHY FROST AND PERHAPS WIDESPREAD FROST ELSEWHERE EARLY SUNDAY MORNING. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 230 PM THURSDAY...GUIDANCE IN DECENT AGREEMENT ON A SERIES OF SHORT WAVES MOVING ACROSS THE AREA IN NEARLY ZONAL FLOW OR FLAT RIDGING ALOFT. A DEEPER TROF BUILDS OVER THE CENTRAL CONUS ON THU AND MOVES TOWARD THE AREA. AT THE SFC...SLY FLOW DEVELOPS ACROSS THE SOUTHEAST ON MON AS THE CENTER OF HIGH PRESSURE MOVES OFF SHORE. THIS FLOW CONTINUES THRU TUE KEEPING THE CHC OF CONVECTION ACROSS THE AREA EACH DAY. A BACK DOOR COLD FRONT MOVES INTO THE VIRGINIAS ON WED...BUT THE MOIST SLY FLOW REMAINS ACROSS OUR CWFA...WITH CONTINUED CHC OF CONVECTION. THE BACK DOOR COLD FRONT THEN SLIDES SOUTH INTO THE CWFA ON THU POTENTIALLY SETTING UP A WEAK CAD. PRECIP CHC WILL REMAIN ACROSS THE AREA GIVEN THE LIFT AND CONTINUED LOW LEVEL MOIST SLY FLOW. ABOVE NORMAL TEMPS MON RISE TO WELL ABOVE NORMAL FOR TUE AND WED...THEN BACK TOWARD NORMAL FOR THU. && .AVIATION /21Z THURSDAY THROUGH TUESDAY/... AT KCLT...THE LAST COUPLE OF HRRR RUNS HAVE LATCHED ONTO CONVECTION DEVELOPING TO THE WEST OF THE AIRFIELD...AND A NARROW TEMPO TSRA WINDOW APPEARS PRUDENT STARTING AT 22Z FOR THE LATEST UPDATE. VFR CIGS IN THE SRLY FLOW LATE THIS AFTN SHOULD RETURN TO MVFR WITH THE ARRIVAL OF THE SHRA/TSRA. MOISTURE CONTINUES TO SPREAD INTO THE AREA OVERNIGHT AS AN UPPER LEVEL DISTURBANCE CROSSES THE REGION AND WITH WEAK UPSLOPE FLOW...CIGS SHOULD DROP TO SOLIDLY MVFR AND LIKELY IFR JUST BEFORE SUNRISE...AROUND 10Z. EXPECT RAPID IMPROVEMENT AFTER 13Z OR SO TO VFR WITH JUST HIGH CLOUDS AROUND BY THE END OF THE PERIOD. ELSEWHERE...THE FIRST ROUND OF LATE DAY CONVECTION HAS GENERALLY MOVED EAST OF THE FOOTHILL TAFS...WITH MAINLY VCSH LINGERING UNTIL EARLY EVENING. THE HRRR FEATURES A SECOND ROUND OF CONVECTION MOVING EAST FROM WRN GA AND CROSSING THE SC SITES MID EVENING. THIS WILL NEED TO BE CLOSELY MONITORED FOR POSSIBLE TEMPO TSRA 00Z TO 03Z. UNCERTAINTY IN FORECAST AREAL COVERAGE OF RAINFALL AND CLOUD COVER THIS EVENING LEADS TO UNCERTAINTY IN OVERNIGHT CIGS ESPECIALLY AT AND...WHERE CIGS COULD DROP TO LIFR OR REMAIN LOW VFR. TOOK A COMPROMISE OF GUIDANCE WITH SOLID MVFR DEVELOPING BUT WILL NEED TO BE MONITORED AS CONFIDENCE IS LOW. EXPECT FASTER LIFTING/CLEARING AT AVL/HKY FRIDAY MORNING THAN OTHER SITES. OUTLOOK...A COLD FRONT WILL PUSH INTO THE AREA FRIDAY NIGHT INTO EARLY SATURDAY. CIG/VSBY RESTRICTIONS SEEM LIKELY AS THE FRONT PUSHES THROUGH AND AT LEAST SHRA IF NOT TSRA ESPECIALLY FOR THE MOUNTAIN TAFS. EVERYTHING SOLIDLY VFR BY 18Z SATURDAY AND REMAINING THERE THROUGH THE REST OF THE WEEKEND...UNTIL YET ANOTHER SYSTEM APPROACHES FOR MONDAY. CONFIDENCE TABLE... 21-03Z 03-09Z 09-15Z 15-18Z KCLT MED 75% MED 73% HIGH 100% HIGH 97% KGSP MED 68% MED 68% HIGH 83% HIGH 100% KAVL HIGH 87% HIGH 93% HIGH 81% HIGH 100% KHKY HIGH 93% HIGH 82% HIGH 100% HIGH 97% KGMU HIGH 89% MED 68% HIGH 85% HIGH 100% KAND MED 62% MED 63% MED 76% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...RWH NEAR TERM...HG/TDP SHORT TERM...ARK LONG TERM...RWH AVIATION...HG/TDP
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
236 PM EDT THU APR 2 2015 .SYNOPSIS... SCATTERED SHOWERS AND THUNDERSTORMS WILL COME TO AN END OVERNIGHT...BUT RETURN FRIDAY AS A COLD FRONT WILL MOVES THROUGH NORTHEAST GEORGIA AND THE WESTERN CAROLINAS FRIDAY EVENING. DRY HIGH PRESSURE MOVES IN FOR THE WEEKEND. MOISTURE WILL RETURN FOR THE START OF THE NEXT WORK WEEK AS SOUTHERLY FLOW DEVELOPS AND PRECIPITATION CHANCES INCREASE THROUGH THE WEEK. && .NEAR TERM /THROUGH FRIDAY/... AS OF 230 PM EDT...INSITU DAMMING HAS BEEN STUBBORNLY PERSISTENT WITH WIDESPREAD CLOUDINESS AND TEMPS STAYING LOWER THAN FORECAST BENEATH THE CLOUD COVER. MIDLEVEL SHORTWAVE AXIS IS PRETTY MUCH OVER THE FORECAST AREA NOW WITH A CONTINUED DAMPING TREND EXPECTED AS IT PUSHES EAST. EXTREME SOUTHERN PORTIONS OF THE FORECAST AREA HAVE STARTED TO CREEP UP IN RESPONSE TO THE PATCHY SUNSHINE AND WITH IT HAS COME AN ATTENDANT INCREASE IN SBCAPES...SPC MESOANALYSIS INDICATING 100-250 J/KG SBCAPE CREEPING INTO THOSE EXTREME SOUTHERN ZONES WITH RAP EXTRAPOLATION SHOWING RAPID INCREASE THROUGH THE AFTERNOON...WITH ONLY A VERY SMALL FINGER OF STABILITY REMAINING ALONG THE LEE OF THE APPALACHIANS BY 22Z...RE-STABILIZING THEREAFTER. NOT SURE I AM COMPLETELY BUYING INTO THE EXTENT OF >500J/KG SBCAPE BUT OVERALL TRENDS DO SEEM REASONABLE. ALREADY SEEING SOME CONVECTION FIRE IN PORTIONS OF GEORGIA SO EXPECT AT LEAST SOME CONVECTION IN SOUTH AND SOUTHWEST ZONES THIS EVENING. SOME CONCERN ABOUT STRONG WINDS AND SMALL HAIL AS LOW-LEVEL WIND SHEAR HAS INCREASED TO 30KT /NOT MUCH TO WRITE HOME ABOUT FOR 0-6KM SHEAR/ WITH WEAK CAA ALOFT THAT WOULD SERVE TO INCREASE LAPSE RATES. SPC DAY1 OUTLOOK CONTINUES TO ADVERTISE GENERAL THUNDER ACROSS THE ENTIRE AREA WITH MARGINAL RISK ACROSS NORTHEAST GEORGIA ZONES SO CONVECTIVE TRENDS WILL NEED TO BE MONITORED. IN THE WAKE OF THE SHORTWAVE...SHOULD SEE A PERIOD OF CLEARING DURING THE DAY TOMORROW WITH INCREASING SOUTHERLY FLOW ALLOWING TEMPERATURES TO RISE WELL ABOVE SEASONAL NORMALS AND QUITE THE DIFFERENCE FROM THOSE TODAY. WOULD NOT BE SURPRISED TO SEE OFF AND ON SHOWER ACTIVITY IN THE MOUNTAINS WITH THE STRONG UPSLOPE FLOW SO HAVE KEPT SLIGHT TO LOW CHANCE POPS ACROSS NORTHERN AND WESTERN ZONES DURING THE DAY. LOW LEVEL LAPSE RATES INCREASE AND WILL HAVE TO WATCH WIND GUST POTENTIAL DURING AFTERNOON MIXING ESPECIALLY AT HIGHER ELEVATIONS. LATE FRIDAY WE START TO SEE THE INFLUENCE OF THE NEXT FRONT THAT WE HAVE BEEN ADVERTISING FOR SEVERAL DAYS NOW... WITH SLIGHT TO LOW CHANCE POPS CREEPING BACK INTO THE MOUNTAIN ZONES LATE IN THE NEAR-TERM PERIOD. BIGGEST CONCERN WITH THE FRONT REMAINS AFTER 00Z FRIDAY INTO THE SHORT TERM PORTION OF THE FORECAST. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... AS OF 215 PM THURSDAY...A BAND OF FRONTAL PRECIP IS EXPECTED TO BE KNOCKING ON THE DOOR OF THE CWFA AROUND 00Z SAT...BUT THE HIGH RES MODELS AND THE NAM/CMC/GFS ALL HAVE SLIGHT DIFFERENCES IN EXACT TIMING. THE ATMOSPHERE UPSTREAM SHUD BE UNSTABLE ENUF WITH PLENTY OF BULK SHEAR TO SUPPORT ORGANIZED STRONG TO SEVERE STORMS ACRS THE TN AND OH VALLEYS. HOWEVER...BY THE TIME THE CONVECTION REACHES THE TN/NC BORDER...INSTBY WILL BE MUCH MORE LIMITED...AND OVERALL WEAKENING IS EXPECTED. A COUPLE OF THE CONVECTION ALLOWING MODELS KEEP A LINE OF STORMS RIGHT UP TO THE NC BORDER. SO A MARGINAL THREAT FOR MAINLY DAMAGING WIND GUSTS...BUT ALSO PERHAPS LARGE HAIL WILL EXIST FRIDAY EVENING IN THE NC MTNS. THE REST OF THE CWFA WILL LIKELY STILL BE RELATIVELY CAPPED...SO LITTLE PRE-FRONTAL DISCRETE CONVECTION IS NOT EXPECTED. THE AMOUNT OF INSTBY IS ALMOST NIL BY 06Z SAT AS THE BAND OF PRECIP IS EXPECTED TO TRY TO ENTER THE PIEDMONT. ALSO...THE 1000-850 MB CONVERGENCE IS WEAK WITH THE FRONT AT THIS POINT. SO AM KEEPING THE 40-60% POP FOR THE EXPECTED AMOUNT OF SHOWER AND POSSIBLE TSTM COVERAGE EAST OF THE MTNS. QPF WILL BE GENERALLY A TENTH OF AN INCH OR LESS OUTSIDE THE MTNS...AND A TENTH TO QUARTER INCH IN THE MTNS. THE WEST-FACING SLOPES OF THE SMOKY MTNS MAY GET A HALF INCH OR MORE. TEMPS WILL BE ELEVATED WITHIN THE FRONTAL ZONE OVERNIGHT...BUT CAA WILL RAMP UP ALONG THE TN LINE TO BRING TEMPS INTO THE 30S WITH A FEW SNOW FLAKES POSSIBLE ABOVE ABOUT 5000 FT. LITTLE OR NO ACCUM EXPECTED. FROM SATURDAY THRU SUNDAY...CONDITIONS SHUD DRY OUT...AS CONTINENTAL HIGH PRES BUILDS IN FROM THE NW. TEMPS ARE EXPECTED TO WARM INTO THE 50S IN THE MTNS AND 60S ACRS THE PIEDMONT BOTH SATURDAY AND SUNDAY. THERE WILL BE SOME LINGERING WIND GUST POTENTIAL ON SATURDAY...AS NWLY CAA FLOW CONTINUES...ESP IN THE MTNS. THIS ON TOP OF LOW RH MAY ELEVATE FIRE WX CONCERNS...ESP IF THE CURRENT QPF IS OVERDONE. SATURDAY NIGHT SHUD BE CHILLY...AS THE CENTER OF HIGH PRES SETTLES INTO THE REGION...RESULTING IN NEARLY IDEAL RADIATIONAL COOLING CONDITIONS. THE LATEST CONSENSUS IS FOR 20S TO MID 30S FOR MOST OF NC...AND MID-UPR 30S ACRS NE GA AND THE UPSTATE. SO EXPECT SOME FREEZING TEMPS...ESP IN THE MTN VALLEYS...AND PATCHY FROST AND PERHAPS WIDESPREAD FROST ELSEWHERE EARLY SUNDAY MORNING. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 230 PM THURSDAY...GUIDANCE IN DECENT AGREEMENT ON A SERIES OF SHORT WAVES MOVING ACROSS THE AREA IN NEARLY ZONAL FLOW OR FLAT RIDGING ALOFT. A DEEPER TROF BUILDS OVER THE CENTRAL CONUS ON THU AND MOVES TOWARD THE AREA. AT THE SFC...SLY FLOW DEVELOPS ACROSS THE SOUTHEAST ON MON AS THE CENTER OF HIGH PRESSURE MOVES OFF SHORE. THIS FLOW CONTINUES THRU TUE KEEPING THE CHC OF CONVECTION ACROSS THE AREA EACH DAY. A BACK DOOR COLD FRONT MOVES INTO THE VIRGINIAS ON WED...BUT THE MOIST SLY FLOW REMAINS ACROSS OUR CWFA...WITH CONTINUED CHC OF CONVECTION. THE BACK DOOR COLD FRONT THEN SLIDES SOUTH INTO THE CWFA ON THU POTENTIALLY SETTING UP A WEAK CAD. PRECIP CHC WILL REMAIN ACROSS THE AREA GIVEN THE LIFT AND CONTINUED LOW LEVEL MOIST SLY FLOW. ABOVE NORMAL TEMPS MON RISE TO WELL ABOVE NORMAL FOR TUE AND WED...THEN BACK TOWARD NORMAL FOR THU. && .AVIATION /19Z THURSDAY THROUGH TUESDAY/... AT KCLT...LOW VFR PREVAILS AT THE AIRPORT BUT WITH MVFR CIGS RIGHT ON THE DOORSTEP. MVFR MIGHT BE IN AND OUT FOR A COUPLE OF HOURS BUT DO EXPECT OVERALL MVFR CIGS TO PUSH IN AND REMAIN FOR SEVERAL HOURS. EXPECT VCSH TO DEVELOP JUST AFTER 00Z AND HAVE BROUGHT IN BRIEF LOW VFR CIGS AGAIN AT THAT TIME. MOISTURE CONTINUES TO SPREAD INTO THE AREA OVERNIGHT AS AN UPPER LEVEL DISTURBANCE CROSSES THE REGION AND WITH WEAK UPSLOPE FLOW...CIGS SHOULD DROP TO SOLIDLY MVFR AND LIKELY IFR JUST BEFORE SUNRISE...AROUND 10Z. EXPECT RAPID IMPROVEMENT AFTER 13Z OR SO TO VFR WITH JUST HIGH CLOUDS AROUND BY THE END OF THE PERIOD...BUT NOT ENOUGH LINES AVAILABLE TO DESCRIBE THIS IN THE TAF. ELSEWHERE...OVERALL SIMILAR IN GENERAL TRENDS TO CLT WITH VCSH AROUND THIS AFTERNOON AND ESPECIALLY EVENING...BUT WEAK INSTABILITY EXPECTED ACROSS UPSTATE SC WARRANTS VCTS AT AND AND MIGHT NEED TO CONSIDER THE SAME FOR GMU/GSP. UNCERTAINTY IN FORECAST AREAL COVERAGE OF RAINFALL AND CLOUD COVER THIS EVENING LEADS TO UNCERTAINTY IN OVERNIGHT CIGS ESPECIALLY AT AND...WHERE CIGS COULD DROP TO LIFR OR REMAIN LOW VFR. TOOK A COMPROMISE OF GUIDANCE WITH SOLID MVFR DEVELOPING BUT WILL NEED TO BE MONITORED AS CONFIDENCE IS LOW. EXPECT FASTER LIFTING/CLEARING AT AVL/HKY FRIDAY MORNING THAN OTHER SITES. OUTLOOK...A COLD FRONT WILL PUSH INTO THE AREA FRIDAY NIGHT INTO EARLY SATURDAY. CIG/VSBY RESTRICTIONS SEEM LIKELY AS THE FRONT PUSHES THROUGH AND AT LEAST SHRA IF NOT TSRA ESPECIALLY FOR THE MOUNTAIN TAFS. EVERYTHING SOLIDLY VFR BY 18Z SATURDAY AND REMAINING THERE THROUGH THE REST OF THE WEEKEND...UNTIL YET ANOTHER SYSTEM APPROACHES FOR MONDAY. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 87% HIGH 83% HIGH 96% HIGH 91% KGSP HIGH 93% MED 71% HIGH 83% HIGH 91% KAVL HIGH 93% HIGH 82% MED 74% HIGH 100% KHKY HIGH 93% HIGH 81% HIGH 94% HIGH 85% KGMU MED 71% MED 72% HIGH 84% HIGH 91% KAND MED 76% MED 71% MED 77% HIGH 96% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...RWH NEAR TERM...TDP SHORT TERM...ARK LONG TERM...RWH AVIATION...TDP
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
159 PM EDT THU APR 2 2015 .SYNOPSIS... HIGH PRESSURE WILL MOVE EAST OF THE AREA TODAY ALLOWING FOR THE RETURN OF MOIST SOUTHERLY FLOW. A COLD FRONT WILL PUSH THROUGH NORTHEAST GEORGIA AND THE WESTERN CAROLINAS ON FRIDAY EVENING AHEAD OF DRIER HIGH PRESSURE FOR THE WEEKEND. MOISTURE WILL RETURN FOR THE START OF THE NEXT WORK WEEK AS SOUTHERLY FLOW INCREASES PRECIPITATION CHANCES THROUGH MIDWEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM EDT...CLOUDINESS HAS EXPANDED ACROSS THE AREA AS ANTICIPATED BUT TEMPERATURES CONTINUE TO RUN A TAD BELOW FORECAST TRENDS AS A RESULT...SO HAVE MADE MINOR ADJUSTMENTS TO HOURLY TRENDS AS WELL AS AFTERNOON HIGH TEMPS. BASED ON HIRES MODEL GUIDANCE... HAVE BACKED OFF POPS ESPECIALLY THROUGH LATE THIS MORNING BUT AFTERNOON TREND WITH POPS AND CONVECTION LOOK FAIRLY SIMILAR TO GOING FORECAST. RAP CONTINUES TO WANT TO BRING IN UPWARDS OF 1000 J/KG SBCAPE INTO WEST AND SOUTHWEST PORTIONS OF THE FORECAST AREA AND WITH WEAK SHEAR PREVIOUS THINKING FOR EVENING CONVECTION REMAINS. OVERALL ONLY MINOR CHANGES TO THE NEAR-TERM FORECAST. FOR TODAY...MOISTURE RETURN FROM THE GULF AND ATLANTIC WILL CONTINUE AS THE UPPER RIDGE AXIS MOVES EAST AND OFFSHORE THIS MORNING...AND A DAMPENING SHORT WAVE APPROACHES FROM THE WEST. THE COMBINATION OF A DEVELOPING LOW LEVEL SE UPSLOPE FLOW AND LOW LEVEL ISENTROPIC UPGLIDE IS EXPECTED TO FORCE LOW CLOUDS AND LIGHT PRECIP THAT WILL EXPAND FROM THE BLUE RIDGE THROUGH MIDDAY AND INTO THE AFTERNOON. HAVE LIMITED THE PRECIP PROBABILITY TO THE CHANCE RANGE INTO THE AFTERNOON. TEMPS WILL BE 5-10 DEGREES COOLER THAN YESTERDAY BECAUSE OF THE EXPANDING LOW CLOUDS AND PRECIP CHANCES. THE WILDCARD IN THE FCST IS THE PASSAGE OF THE SHORTWAVE THIS AFTERNOON. THE FORCING ASSOCIATED WITH THE WAVE SHOULD INTERSECT AN UNSTABLE BOUNDARY LAYER ACRS N/NE GEORGIA AND HELP TO TRIGGER SOME DEEPER CONVECTION...WHICH THE MODELS CARRY EASTWARD ACROSS UPSTATE SC AND THE SRN PIEDMONT OF NC INTO THIS EVENING. FOR NOW...WILL LIMIT THE FCST TO THE LOWER END OF THE CHC RANGE OUT OF UNCERTAINTY WITH HOW MUCH DESTABILIZATION WILL ACTUALLY OCCUR. FOR TONIGHT...THE PASSAGE OF THE WAVE WILL BRING THE LOW LEVEL FLOW AROUND TO SOMETHING MORE S OR SW...AND WILL ALSO PUSH THE BEST ISENTROPIC UPGLIDE AWAY TO THE NE. THAT SHOULD SLOWLY ELIMINATE OUR PRECIP POTENTIAL INTO THE EARLY MORNING HOURS. THE MODELS SUGGEST THERE WILL BE A LULL BY AROUND DAYBREAK FRIDAY AS WE AWAIT THE ARRIVAL OF THE MAIN COLD FRONT. MIN TEMPS SHOULD BE MILD. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 AM EDT THURSDAY...THE SHORT TERM FCST PERIOD INITIALIZES FRIDAY MORNING AMIDST A DEPARTING SHORTWAVE TROF LEAVING QUASI ZONAL FLOW BEHIND OVER THE SOUTHEAST. FURTHER WEST...A SERIES OF WAVES ALOFT...ONE NORTHERN STREAM...AND ONE IN THE SOUTHERN STREAM ARE FCST TO PHASE AS THEY ENTER THE ARKLATEX REGION BY MIDDAY FRIDAY. SURFACE CYCLOGENESIS WILL BE UNDERWAY...AND WILL LIKELY INTENSIFY AS THE ABOVE MENTIONED PHASING HAPPENS ALOFT. A COLD FRONT STRETCHING FROM THE NORTHERN OH VALLEY SOUTHWARD TO THE GULF COAST WILL ADVECT EAST THROUGH THE DAY INTERACTING WITH A MOIST/UNSTABLE WARM SECTOR OVER THE MIDSOUTH WHERE LATEST NAM/GFS GUIDANCE FAVORS UPWARDS OF 1200-1500J/KG SBCAPE ALONG WITH A 40-50KT LLJ PROVIDING AMPLE SHEAR. FURTHER EAST OVER THE SOUTHERN APPS...DESPITE CONTINUED SOUTHERLY FLOW...DEWPOINTS ARE NOT ALL THAT IMPRESSIVE AS A POCKET OF RELATIVELY DRIER GULF AIR ADVECTS IN EARLY ON FRIDAY. THEREFORE...EXPECTING A LINE OF STRONG/SEVERE CONVECTION TO PUSH EAST THROUGH THE TN VALLEY LATE DAY FRIDAY BEFORE SLIDING INTO THE WESTERN NC MOUNTAINS AROUND MIDNIGHT. THIS LINE SHOULD WEAKEN AS IT ENTERS THE HIGH TERRAIN AS THE AIRMASS WILL NOT BE AS FAVORABLE FOR SUSTAINMENT. THAT SAID...AS THE LLJ ADVECTS INTO THE REGION AHEAD OF THE PRIMARY SURFACE TROF...MODELS CONTINUE TO FCST NEARLY 30KTS 0-3KM BULK SHEAR WITH SRH VALUES IN EXCESS OF 250 M2/S2 THROUGH THE SAME LAYER WHICH COULD SUPPORT STRONG CONVECTION OVER THE NC HIGH COUNTRY AND NORTHEAST GA. ACROSS THE LOWER TERRAIN EXPECTING AN EVEN MORE STABLE...LESS SHEARED ENVIRONMENT TO BE IN PLACE WHICH WOULD FAVOR MORE GENERAL SHOWERS/THUNDERSTORMS OVERNIGHT WITH THE FROPA. BY SATURDAY MORNING THE FRONT WILL BE EXITING THE REGION TO THE EAST WITH HIGH PRESSURE SPILLING IN. MODELS CONTINUE TO FAVOR A BAND OF LLV MOISTURE BANKED UP AGAINST THE WESTERN SLOPES OF THE NC MOUNTAINS BEHIND THE FRONT AROUND MIDDAY. THUS ALTHOUGH CONFIDENCE IS LOW...FALLING THICKNESSES COULD YIELD A BRIEF RAIN/SNOW SHOWER OR TWO ACROSS THE HIGHER PEAKS AND RIDGETOPS OF THE NORTHERN NC MOUNTAINS WHICH WILL NOT YIELD ANY ACCUMULATION. OTHERWISE...SKIES WILL CLEAR OUT THROUGH THE DAY ON SATURDAY AS BRIEF NORTHWEST WINDS AID DOWNSLOPING FLOW WITH HIGHS TOPPING OUT A FEW DEGREES BELOW NORMAL. AS THE SURFACE HIGH SLIDES OVERHEAD SATURDAY NIGHT...EXPECTING GOOD RADIATIONAL COOLING CONDITIONS AIDED BY LIGHT/CALM SURFACE FLOW. MODELS HAVE TRENDED SLIGHTLY COOLER FOR SUNDAY MORNING...THUS WILL MENTION FREEZE CONDITIONS POSSIBLE OVER THE SOUTHWEST NC MOUNTAINS WHILE ALSO ADDING WORDING FOR FROST OUTSIDE OF THE MOUNTAINS AS LOWS FALL TO NEARLY 15-20 DEGREES BELOW NORMAL. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 330 AM EDT THURSDAY...THE MEDIUM RANGE FCST PERIOD INITIALIZES SUNDAY MORNING AMIDST PATCHY/WIDESPREAD FROST AND OR FREEZE CONDITIONS AS SURFACE HIGH PRESSURE PREVAILS OVERHEAD. MODELS FAVOR SAID HIGH PRESSURE SLIDING EAST THROUGH THE DAY WITH A DRY...YET COOL EASTER HOLIDAY IN STORE. AS THE RIDGE SETS UP OFFSHORE...SOUTHERLY FLOW WILL RETURN ACROSS THE SOUTHEAST INTO THE NEW WORK WEEK YIELDING INCREASED MOISTURE AND PRECIPITATION CHANCES ON MONDAY AS A WEAK SHORTWAVE SLIDES THROUGH THE TN VALLEY REGION. PRECIPITATION CHANCES WILL REMAIN ELEVATED THROUGH THE PERIOD AS MODELS CONTINUE TO PREVAIL BROAD WAA REGIME OVER THE SOUTHEAST LEADING TO UNSETTLED WEATHER HIGHLIGHTED BY POTENTIAL DIURNAL SHOWERS AND THUNDERSTORMS...ALONG WITH WEAK UPSLOPE INDUCED PRECIPITATION OVER THE HIGH TERRAIN. THAT SAID...CONFIDENCE REMAINS MODEST AT BEST REGARDING DIURNAL CHANCES AS MODELS INDICATE BROAD UPPER RIDGING WILL ESTABLISH ITSELF BY MIDWEEK EFFECTIVELY HELPING TO TAMP DOWN CONVECTION. LATE IN THE PERIOD BOTH THE GFS/ECMWF FAVOR POSSIBLE CAD EXTENSION FROM PARENT HIGH PRESSURE ATOP THE NORTHEAST AHEAD OF A DEVELOPING SYSTEM OVER THE ARKLATEX...ALL WARRANTING CONTINUED POPS DUE TO UNCERTAINTY OF ANY POSSIBLE UPGLIDE REGIME ESTABLISHMENT ALONG WITH ABOVE MENTIONED DIURNAL PRECIPITATION CHANCES. TEMPERATURES THROUGH THE PERIOD WILL GRADUALLY MODERATE AMONGST WAA REGIME LEADING TO ABOVE NORMAL TEMPERATURES BY MIDWEEK. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... AT KCLT...LOW VFR PREVAILS AT THE AIRPORT BUT WITH MVFR CIGS RIGHT ON THE DOORSTEP. MVFR MIGHT BE IN AND OUT FOR A COUPLE OF HOURS BUT DO EXPECT OVERALL MVFR CIGS TO PUSH IN AND REMAIN FOR SEVERAL HOURS. EXPECT VCSH TO DEVELOP JUST AFTER 00Z AND HAVE BROUGHT IN BRIEF LOW VFR CIGS AGAIN AT THAT TIME. MOISTURE CONTINUES TO SPREAD INTO THE AREA OVERNIGHT AS AN UPPER LEVEL DISTURBANCE CROSSES THE REGION AND WITH WEAK UPSLOPE FLOW...CIGS SHOULD DROP TO SOLIDLY MVFR AND LIKELY IFR JUST BEFORE SUNRISE...AROUND 10Z. EXPECT RAPID IMPROVEMENT AFTER 13Z OR SO TO VFR WITH JUST HIGH CLOUDS AROUND BY THE END OF THE PERIOD...BUT NOT ENOUGH LINES AVAILABLE TO DESCRIBE THIS IN THE TAF. ELSEWHERE...OVERALL SIMILAR IN GENERAL TRENDS TO CLT WITH VCSH AROUND THIS AFTERNOON AND ESPECIALLY EVENING...BUT WEAK INSTABILITY EXPECTED ACROSS UPSTATE SC WARRANTS VCTS AT AND AND MIGHT NEED TO CONSIDER THE SAME FOR GMU/GSP. UNCERTAINTY IN FORECAST AREAL COVERAGE OF RAINFALL AND CLOUD COVER THIS EVENING LEADS TO UNCERTAINTY IN OVERNIGHT CIGS ESPECIALLY AT AND...WHERE CIGS COULD DROP TO LIFR OR REMAIN LOW VFR. TOOK A COMPROMISE OF GUIDANCE WITH SOLID MVFR DEVELOPING BUT WILL NEED TO BE MONITORED AS CONFIDENCE IS LOW. EXPECT FASTER LIFTING/CLEARING AT AVL/HKY FRIDAY MORNING THAN OTHER SITES. OUTLOOK...A COLD FRONT WILL PUSH INTO THE AREA FRIDAY NIGHT INTO EARLY SATURDAY. CIG/VSBY RESTRICTIONS SEEM LIKELY AS THE FRONT PUSHES THROUGH AND AT LEAST SHRA IF NOT TSRA ESPECIALLY FOR THE MOUNTAIN TAFS. EVERYTHING SOLIDLY VFR BY 18Z SATURDAY AND REMAINING THERE THROUGH THE REST OF THE WEEKEND...UNTIL YET ANOTHER SYSTEM APPROACHES FOR MONDAY. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 87% HIGH 83% HIGH 96% HIGH 91% KGSP HIGH 93% MED 71% HIGH 83% HIGH 91% KAVL HIGH 93% HIGH 82% MED 74% HIGH 100% KHKY HIGH 93% HIGH 81% HIGH 94% HIGH 85% KGMU MED 71% MED 72% HIGH 84% HIGH 91% KAND MED 76% MED 71% MED 77% HIGH 96% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...CDG/RWH NEAR TERM...PM/TDP SHORT TERM...CDG LONG TERM...CDG AVIATION...TDP
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
325 PM MDT THU APR 2 2015 .SYNOPSIS... IT APPEARS THAT SPRING IS ON THE WAY...JUST A MONTH LATER THAN NORMAL. THE UPCOMING WEEK IS LOOKING VERY TYPICAL OF SPRING WEATHER AS STRONG DRY WEST FLOW ALOFT DOMINATES MUCH OF THE WEEK. ABOVE NORMAL TEMPERATURES AND BREEZY AFTERNOONS WILL CHARACTERIZE MUCH OF THIS PERIOD. THE ONE EXCEPTION WILL BE SATURDAY...WHEN A COOL FRONT MOVES IN FROM THE EAST AND GIVES THE BORDERLAND A SLIGHT CHANCE OF THUNDERSTORMS. OTHERWISE DRY WITH ABOVE NORMAL TEMPERATURES AND WINDY DAYS ON MONDAY AND TUESDAY. && .DISCUSSION... WELL BETTER LATE THAN NEVER...OUR MARCH WEATHER HAS BEGUN IN EARLY APRIL! STRONG ZONAL FLOW IS SET UP WITH THE MAIN STORM TRACK WELL TO OUR NORTH. WINDY DAY ACROSS THE CWA TODAY AS MODERATE MID LEVEL WINDS HAVE MIXED DOWN TO THE SURFACE. HRRR SHOWED NICE MESOSCALE LEE-SIDE TROUGH FORMING LATE THIS MORNING ALONG EASTERN SACS BUT LATER ABSORBED INTO SYNOPTIC SCALE. THOUGH WINDS WILL REMAIN GUSTY OVER THE SACS...THIS MOVEMENT NORTHEAST OF THE LEE SIDE TROUGH PROBABLY WILL KEEP WINDS JUST BELOW ADVISORY THERE. NONE THE LESS WILL LET THE ADVISORY EXPIRE THIS EVENING AS WINDS ARE PRETTY CLOSE. WINDS DROPPING OFF FRIDAY AS WEAK BACK DOOR FRONT MOVES INTO EASTERN NEW MEXICO AND DISRUPTS LEE SIDE TROUGHING. WIND SHIFT MAY ACTUALLY MOVE INTO CWA FRIDAY AFTERNOON BUT MAIN FRONT WITH COOLING WON`T MOVE IN TIL FRIDAY NIGHT. THIS WILL COOL SATURDAY DOWN TO NEAR NORMAL BUT ALSO BRING IN LOW LEVEL MOISTURE. MODELS MOVE FRONT OUT BETWEEN CONT DIVIDE AND ARIZONA BORDER SATURDAY AFTERNOON. NAM 12 SHOWS NICE CONVERGENCE ZONE IN THIS AREA WITH NARROW BAND OF MODERATE INSTABILITY. BELIEVE ISOLD MOUNTAIN THUNDERSTORMS WILL DEVELOP BY MID DAY. BY MID AFTERNOON SLIGHT CHANCE OF THUNDERSTORMS ALONG THIS CONVERGENCE ZONE FROM SILVER CITY TO HACHITA.. AREAS FURTHER EAST STABILIZED OUT POST FRONTALLY...BUT STORM MOTION MAY WELL PUSH THE CONVERGENCE LINE STORMS EASTWARD INTO THE RIO GRANDE VALLEY. UPPER TROUGH MOVES THROUGH SUNDAY MORNING WITH SURFACE WINDS TURNING BACK TO SOUTHWEST. THIS WILL QUICKLY FLUSH LOW LEVEL MOISTURE EAST OUT OF THE AREA. MONDAY/TUESDAY LOOK TO BE BREEZY TO WINDY AS DECENT LEE SIDE TROUGHING DEVELOPS WITH MODERATE MID LEVEL WINDS. NEXT PACIFIC LOW APPROACHES AREA ON WEDNESDAY. GOOD PATHCAST FOR THE STORM BUT TIMING IS A BIT OFF REACHING THE FOUR CORNERS AREA A LITTLE EARLY. STILL WINDY ON WEDNESDAY BUT THIS TIMING WOULD SUGGEST MISSING OUT ON STRONGER WINDS. FURTHER CARVING SOUTHWARD OF THE LOW ON THURSDAY WILL ALLOW ANOTHER BACK DOOR FRONT INTO THE AREA THURSDAY NIGHT. THIS COULD GIVE US A CHANCE OF RAIN FRIDAY BUT STILL BEYOND THE FORECAST PERIOD. && .AVIATION...VALID 03/00Z-04/00Z... VFR CONDITIONS THRU PERIOD WITH P6SM FEW-SCT250. STRONG SFC WINDS STARTING AT 00Z THRU 08Z. WINDS AT KELP WILL MEET AWW CRITERIA FROM 00Z-03Z EXPECT 25023G30KT WINDS. WIND SPEEDS WILL BEGIN TO DECREASE AFTR 03Z AND DROP BACK TO OR BELOW 12 KTS AFTER 09Z. && .FIRE WEATHER... WESTERLY FLOW ALOFT WITH STRONG SURFACE WINDS WILL CONTINUE INTO THE EARLY EVENING HOURS. A RED FLAG WARNING IS IN EFFECT UNTIL 9PM FOR ALL FIRE ZONES WHEN SURFACE WINDS WILL FALL BELOW CRITICAL LEVELS. FRIDAY WINDS WILL FURTHER DIMINISH AND SHIFT TO THE NORTH AS A COOL FRONT MOVES INTO THE BORDERLAND. HIGH TEMPS FRIDAY WILL REMAIN ABOVE NORMAL THEN DROP TO NEAR NORMAL VALUES ON SATURDAY BEHIND THE FRONT. SATURDAY WINDS WILL SHIFT EAST TRANSPORTING SOME GULF MOISTURE INTO THE AREA. THIS WILL RESULT IN INCREASED CHANCES FOR ISOLATED RAIN SHOWERS AND THUNDERSTORMS ACROSS MUCH OF THE AREA ESPECIALLY IN THE MOUNTAIN ZONES SATURDAY AND SATURDAY NIGHT. SUNDAY THROUGH THE MIDDLE OF NEXT WEEK...WEST TO SOUTHWEST FLOW RETURNS WITH DAYTIME TEMPS GETTING BACK ABOVE NORMAL AND BREEZY TO WINDY CONDITIONS WILL PREVAIL DURING THE AFTERNOONS. RH VALUES WILL REMAIN IN THE SINGLE DIGITS FRIDAY AND INCREASE ACROSS THE REGION SATURDAY. SATURDAY MIN RH VALUES WILL BE IN THE MID 20S TO UPPER 30S EXCEPT IN THE FAR WEST WHERE THEY WILL REMAIN IN THE TEENS. VENT RATES WILL BE FAIR TO GOOD ON FRIDAY AND POOR ON SATURDAY. && .PRELIMINARY POINT TEMPS/POPS... EL PASO 57 81 50 71 49 / 0 0 0 0 20 SIERRA BLANCA 52 78 44 67 42 / 0 0 0 0 10 LAS CRUCES 52 79 44 71 42 / 0 0 0 0 20 ALAMOGORDO 48 76 44 70 42 / 0 0 0 0 10 CLOUDCROFT 36 57 30 51 30 / 0 0 0 10 10 TRUTH OR CONSEQUENCES 44 74 44 69 42 / 0 0 0 0 20 SILVER CITY 40 70 42 67 40 / 0 0 0 0 20 DEMING 44 78 44 73 41 / 0 0 0 0 20 LORDSBURG 43 79 44 75 42 / 0 0 0 0 10 WEST EL PASO METRO 56 79 51 72 50 / 0 0 0 0 20 DELL CITY 49 80 44 67 40 / 0 0 0 10 10 FORT HANCOCK 53 83 50 71 46 / 0 0 0 0 10 LOMA LINDA 52 73 43 65 44 / 0 0 0 0 20 FABENS 53 82 48 71 46 / 0 0 0 0 20 SANTA TERESA 53 80 47 72 46 / 0 0 0 0 20 WHITE SANDS HQ 52 76 47 70 45 / 0 0 0 0 20 JORNADA RANGE 41 76 40 71 37 / 0 0 0 0 20 HATCH 46 77 44 72 40 / 0 0 0 0 20 COLUMBUS 49 78 48 73 45 / 0 0 0 0 20 OROGRANDE 51 77 47 68 44 / 0 0 0 0 20 MAYHILL 41 64 33 57 34 / 0 0 0 10 10 MESCALERO 37 65 33 59 33 / 0 0 0 10 10 TIMBERON 40 65 35 56 34 / 0 0 0 10 10 WINSTON 36 67 36 63 34 / 0 0 0 10 10 HILLSBORO 43 72 40 67 40 / 0 0 0 0 20 SPACEPORT 41 75 40 70 37 / 0 0 0 0 20 LAKE ROBERTS 36 69 37 64 33 / 0 0 0 10 20 HURLEY 41 72 41 67 39 / 0 0 0 0 20 CLIFF 36 76 37 74 36 / 0 0 0 0 20 MULE CREEK 32 74 34 72 31 / 0 0 0 0 0 FAYWOOD 42 72 42 67 40 / 0 0 0 10 20 ANIMAS 45 79 47 77 42 / 0 0 0 0 0 HACHITA 43 79 44 76 41 / 0 0 0 0 20 ANTELOPE WELLS 44 80 45 77 41 / 0 0 0 0 0 CLOVERDALE 44 76 45 76 40 / 0 0 0 0 0 && .EPZ WATCHES/WARNINGS/ADVISORIES... NM...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR NMZ110>113. WIND ADVISORY UNTIL 8 PM MDT THIS EVENING FOR NMZ414>416. TX...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR TXZ055-056. && $$ HEFNER/PAZOS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
340 PM MDT THU APR 2 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 310 PM MDT THU APR 2 2015 WEBCAMS CONTINUE TO SHOW SNOW HAVING TROUBLE STICKING TO THE ROADS...WHICH MAKES SENSE GIVEN THE WARM MARCH...THE CURRENT HIGH SUN ANGLE...AND SFC TEMPS GENERALLY AROUND FREEZING. DID HAVE A BAND OF HEAVIER SNOW AROUND MIDDAY THAT STRETCHED FROM WHITAKER TO GUN BARREL...PRODUCING 1-2 INCHES OF SNOW...BUT THAT HAS SINCE WEAKENED. RADAR IMAGERY INDICATES THAT SNOW IS BEGINNING TO LET UP ACROSS LARAMIE COUNTY AND EXPECT THIS TREND TO CONTINUE THROUGH THE EVENING. THE HRRR DOES SHOW THE HEAVIER PRECIP SHIFTING INTO THE SOUTHERN NEBRASKA PANHANDLE (MAINLY KIMBALL AND CHEYENNE COUNTIES) AND THAT AREA COULD PICK UP AN INCH OR SO THROUGH 03Z. KEPT THE WINTER WEATHER ADVISORY GOING FOR THE SOUTHERN LARAMIE RANGE THROUGH THE EVENING AS TEMPS ARE IN THE LOW 20S UP THERE...AND THIS ZONE WOULD HAVE THE BEST CHANCE OF ACCUMULATING SNOW ON INTERSTATE 80 AFTER SUNSET...EVEN THOUGH THE RATES WILL BE DECREASING. PROGRESSIVE SHORTWAVE RESPONSIBLE FOR TODAYS PRECIPITATION WILL MOVE QUICKLY INTO NEBRASKA TONIGHT WITH PRECIP LARGELY SHUTTING OFF AFTER 06Z. IT WILL A COLDER NIGHT WITH WIDESPREAD LOWS IN THE 20S. THE REMAINDER OF THE SHORT TERM WILL BE RATHER QUIET. HEIGHTS RISE SLIGHTLY ON FRIDAY...HOWEVER HIGHS WILL STRUGGLE TO GET OUT OF THE 40S OVER MOST OF THE AREA WITH 700MB TEMPS OF -10C. MORE SUBSTANTIAL WARMING WILL OCCUR ON SAT AS 700MB TEMPS RISE TO 2C. WILL HAVE TO WATCH OUT FOR CRITICAL FIRE WEATHER CONDITIONS ACROSS CONVERSE AND NIOBRARA COUNTIES ON SATURDAY AFTN. SOUNDINGS AT DGW SHOW 25-30 KTS AT THE TOP OF THE MIXED LAYER AND RH VALUES AROUND 15 PERCENT. WINDS WILL BE WEAKER AND RH VALUES WILL BE HIGHER FURTHER SOUTH...SO NO FIRE WEATHER CONCERNS ANTICIPATED OVER LARAMIE AND PLATTE COUNTIES. .LONG TERM...(SUNDAY THROUGH WEDNESDAY NIGHT) ISSUED AT 310 PM MDT THU APR 2 2015 MODELS CONTINUE TO SHOW ENERGETIC SOUTHWEST FLOW OVERHEAD FOR SUNDAY AND MONDAY AHEAD OF AN UPPER LOW MOVING INTO THE PAC NW. A SFC LOW PRESSURE TROUGH LOOKS TO REMAIN IN PLACE OVER THE ROCKIES THRU THIS TIME IN ADVANCE OF THE UPPER LOW...WITH GUSTY WEST-SOUTHWEST WINDS EXPECTED ALONG AND WEST OF THE LARAMIE RANGE BOTH SUNDAY AND MONDAY. ACROSS THE PLAINS...WINDS WILL BE MORE OF A EAST-SOUTHEAST FETCH ON SUNDAY LIKELY TURNING WESTERLY BY MONDAY AFTERNOON. MODELS RESOLVE A SORT OF SPLIT JET ORIENTATION WHICH WILL KEEP DEEPEST MOISTURE BOTH NORTH AND SOUTH OF THE CWA...AND CONDITIONS SHOULD REMAIN MOSTLY DRY AS A RESULT. A FEW SPRINKLES ARE POSSIBLE NEAR THE MOUNTAINS ON SUNDAY AS SHALLOW CONVECTION COULD DEVELOP WITHIN THE SFC WIND CONVERGENCE ZONE AND UPSLOPE FLOW. THIS CONVERGENCE BOUNDARY WILL SHIFT EAST ON MONDAY IN RESPONSE TO A STRONGER EMBEDDED MIDLEVEL SHORTWAVE TROUGH MOVING OVER THE ROCKIES IN THE AFTERNOON. WILL SEE SOUTHWESTERLY WINDS IN THE WAKE OF THE SFC TROUGH BECOME QUITE GUSTY AS THE GRADIENT STRENGTHENS AND H7 WINDS INCREASE TO AROUND 40KTS...WITH PERHAPS A FEW MORE LIGHT SHOWERS DEVELOPING ALONG THE SFC CONVERGENCE BOUNDARY AND OVER THE MOUNTAINS AS THE WAVE PASSES OVERHEAD. OVERALL LACK OF DEEP MOISTURE WILL KEEP CONVECTION AND QPF MINIMAL SO KEPT MAINLY SLIGHT CHANCE POPS FOR THIS SCENARIO. HEIGHTS ALOFT WILL THEN DECREASE THROUGH MIDWEEK AS THE UPPER LOW OPENS UP TO A TROUGH AND MOVES EASTWARD OVER THE ROCKIES. GFS IS GENERALLY STRONGER WITH THIS FEATURE THROUGH WEDNESDAY NIGHT WHILE THE ECMWF WEAKENS IT CONSIDERABLY WEDNESDAY AND WEDNESDAY NIGHT. WILL MAINTAIN THE TREND FOR INCREASING POPS TUESDAY THROUGH WEDNESDAY AS THE UPPER TROUGH APPROACHES FROM THE WEST AND SFC COLD FRONT DROPS SOUTH ACROSS THE FORECAST AREA...WITH A STEADY DECREASE WEDNESDAY NIGHT AS THE WAVE WEAKENS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1120 AM MDT THU APR 2 2015 LATEST HRRR GUIDANCE USED FOR THE 18Z TAFS. SHOWING ANOTHER BAND OF SNOW DEVELOPING EARLY THIS AFTERNOON AND PERSISTING THROUGH ROUGHLY 02-03Z THIS EVENING FOR KCYS...KLAR AND KRWL. SOUTHERN PANHANDLE COULD BE IMPACTED LATER THIS AFTERNOON INCLUDING THE AIRPORTS OF KBFF AND KSNY. SNOW THEN EXITS SOUTHEAST WITH VFR CONDITIONS RETURNING. && .FIRE WEATHER... ISSUED AT 310 PM MDT THU APR 2 2015 AFTER COOL AND MOIST CONDITIONS...TEMPERATURES WILL BEGIN TO MODERATE AS WE HEAD INTO THE WEEKEND. THE COMBINATION OF WARMER TEMPERATURES AND A DRY AIRMASS WILL CAUSE MINIMUM AFTERNOON HUMIDITY VALUES TO FALL TO 15-20 PERCENT ON SATURDAY AND SUNDAY. CRITICAL FIRE WEATHER CONDITIONS COULD BE POSSIBLE ACROSS CONVERSE AND NIOBRARA COUNTIES ON SATURDAY AFTERNOON AS WEST WINDS GUST TO 30 MPH AND RH VALUES FALL TO AROUND 15 PERCENT. THIS AREA HAS ALSO RECEIVED VERY LITTLE PRECIPITATION FROM THE CURRENT STORM SYSTEM. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR WYZ116. WINTER WEATHER ADVISORY UNTIL 3 AM MDT FRIDAY FOR WYZ114. NE...NONE. && $$ SHORT TERM...ZF LONG TERM...RJM AVIATION...GCC FIRE WEATHER...ZF
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1123 AM MDT THU APR 2 2015 .UPDATE... ISSUED AT 1040 AM MDT THU APR 2 2015 NO BIG CHANGES MADE TO THE FCST THROUGH THE AFTN. BAND OF PRECIP IS CURRENTLY MOVING OVER AREAS ALONG INTERSTATE 80 TO THE EAST OF THE LARAMIE RANGE. SNOW IS FALLING FROM THE SOUTHERN LARAMIE RANGE TO PINE BLUFFS WITH A MIX OF RAIN AND SNOW BEING REPORTED AT KIMBALL. WEBCAMS INDICATE THAT SNOW IS ACCUMULATING ON GRASSY SURFACES BUT NOT ON THE ROADS...EXCEPT FOR THE INTERSTATE 80 SUMMIT WHERE WE CURRENTLY HAVE AN ADVISORY IN EFFECT. IT IS STILL POSSIBLE THAT SNOW COULD ACCUMULATE BRIEFLY ON ROADS IN LARAMIE COUNTY THROUGH THE AFTERNOON...BUT IT WILL LIKELY HAVE TO BE A BAND OF HEAVIER SNOW. THE MODELS CONTINUE TO SHOW PRECIP TAPERING OFF ACROSS THE PLAINS AFTER 00Z. && .SHORT TERM...(TODAY THROUGH SATURDAY NIGHT) ISSUED AT 420 AM MDT THU APR 2 2015 MAIN FORECAST CHALLENGE IS THE SNOW ACCUMULATION FORECAST FOR TODAY. MODELS CONTINUE TO REMAIN FAIRLY CONSISTENT WITH THE PLACEMENT AND TIMING OF A CANADIAN COLD FRONT AND PACIFIC UPPER LEVEL ENERGY TODAY. THE MAIN UPPER LEVEL JET CORE WILL REMAIN WELL SOUTH OF THE AREA NEAR THE COLORADO AND NEW MEXICO BORDER... HOWEVER SOUTHEAST WYOMING WILL STILL BE IN THE LEFT EXIT REGION OF THE JET FOR MUCH OF TODAY. THIS AREA WILL ALSO BE INFLUENCED BY DIFLUENT/DIVERGENT FLOW ALOFT AND PVA AHEAD OF THE CENTER OF SHORTWAVE ENERGY MOVING EAST ACROSS COLORADO. THIS IS NOT THE MOST DYNAMIC SYSTEM BUT STRONGER THEN ANYTHING OVER THE PAST FEW WEEKS. THE UPPER LEVELS WILL INTERACT WITH MID LEVEL ISENTROPIC LIFT THIS AFTERNOON AND WITH THE CANADIAN COLD FRONT FOR A BRIEF PERIOD IN THE AFTERNOON. THE COMBINATION WILL MAKE FOR A PERIOD OF PRECIPITATION MAINLY OVER THE SOUTHERN HALF OF THE FORECAST AREA TODAY WITH THE MAIN PRECIPITATION ALONG THE INTERSTATE 80 CORRIDOR. MANY COMPETING FACTORS MAKE THE SNOW ACCUMULATION FORECAST TODAY MORE DIFFICULT THAT NORMAL. ACCUMULATIONS WILL LARGELY BE BASED ON NOT ONLY SURFACE TEMPERATURES BUT ALSO CRYSTAL TYPE AND OVERALL SNOWFALL RATES. IN GENERAL IT LOOKS LIKE SNOW RATES WILL BE ON THE LIGHTER SIDE...SUCH AT .1 TO .2 INCHES PER HOUR...WHICH WHEN OCCURRING WITH AN EARLY APRIL SUN ANGLE WILL TEND TO MELT... ESPECIALLY ON SURFACES SUCH AS ROADS. HOWEVER...WHEN THE COLD FRONT PUSHES THROUGH THE AREA EARLY THIS AFTERNOON...SNOW WILL INTENSITY WITH HIGHER RATES. SNOW WILL LIKELY BECOME HEAVY FOR A FEW HOURS FOLLOWING FROPA AT WHICH TIME SNOW RATES AROUND .5 INCHES OR MORE PER HOUR SHOULD OVERCOME MELTING. ITS AT THIS TIME ROADS COULD BECOME SLUSHY TO EVEN SNOW COVERED. GIVEN THE COOLER TEMPERATURES OVER THE SUMMIT...DECIDED TO ISSUE A WINTER WEATHER ADVISORY FOR ZONE 116...EVEN THROUGH SNOW ACCUMULATIONS WILL BE BELOW AMOUNTS TYPICALLY NEEDED FOR AN ADVISORY IN A MOUNTAIN ZONE. THE ADVISORY WAS ISSUED AS ROADS SHOULD BECOME SNOW COVERED THIS AFTERNOON AND POTENTIAL VERY ICY...MAKING FOR DIFFICULT TRAVEL THROUGH THAT AREA. AT LOWER ELEVATIONS NOT EXPECTING HEAVY SNOW TO LAST LONG ENOUGH TO CREATE MUCH IN THE WAY OF TRAVEL PROBLEMS THIS AFTERNOON BUT MAY HAVE SOME BLACK ICE CONCERNS THIS EVENING...FORTUNATELY SNOW WILL TAPER OFF THIS EVENING. OVERALL NOT EXPECTING MAJOR IMPACTS TO TRAVEL OUTSIDE OF THE MOUNTAINS...BUT CERTAINLY SOMETHING TO KEEP A CLOSE EYE ON THIS AFTERNOON. THE QUICK MOVING PACIFIC SYSTEM WILL PUSH INTO THE PLAINS THIS EVENING...WITH MOST SNOW ENDING EARLY EVENING AND LIMITING OVERALL IMPACTS. BELOW 5000 FEET...LITTLE TO NO SNOW ACCUMULATION IS EXPECTED. SOME LIGHT SNOW WILL LINGER INTO LATE TONIGHT ACROSS THE FAR WESTERN FORECAST AREA AND CAN NOT RULE OUT A FEW SNOW SHOWERS INTO FRIDAY MORNING...BUT BY FRIDAY AFTERNOON ALL SNOW WILL END WITH SKIES CLEARING OUT ACROSS THE FORECAST AREA. TEMPERATURES WILL BE ON THE COOL SIDE THROUGH FRIDAY BUT WILL BEGIN TO MODERATE GOING INTO THE WEEKEND. DRY SATURDAY WITH CLEAR TO PARTLY CLOUD SKIES BUT IT WILL BE A BIT WINDY OVER SOUTHEAST WYOMING DURING THE AFTERNOON. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 334 AM MDT THU APR 2 2015 A MILD AND WINDY START TO THE EXTENDED FORECAST PERIOD. SUBSIDENCE BENEATH BROAD UPPER-LEVEL RIDGING WILL KEEP ANY CHANCES FOR PRECIP AT BAY ON SUNDAY WHILE PROMOTING PLENTY OF SUNSHINE. EXCELLENT LLVL MIXING IS EXPECTED IN THE AFTN AND EARLY EVE AS INCREASING GRADIENTS ALLOW WINDS ALOFT TO INCREASE. GFS BUFKIT SOUNDINGS STILL SHOW NEAR DRY ADIABATIC LAPSE RATES TO AT LEAST 500 HPA WITH A SOLID CORE OF 40 TO 50 KT FLOW NOT FAR OFF THE SFC ABOVE KRWL. WITH UNIDIRECTIONAL SOUTHWEST FLOW THROUGH MUCH OF THE COLUMN...HIGH WIND HEADLINES CAN NOT BE ENTIRELY RULED OUT LATE IN THE WEEKEND. MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT WITH A TRANSITION TO A COOLER...WETTER...AND GENERALLY MORE ACTIVE WEATHER PATTERN INTO NEXT WEEK. THE GFS/ECMWF HAVE BOTH TRENDED A LITTLE FASTER WITH A PACIFIC SHORTWAVE STARTING TO MOVE INTO NORTHERN CAL ON MON MORNING. THIS ENERGY SHOULD EJECT NORTHEAST TOWARD THE NORTHERN PLAINS BY MON NIGHT...SO OUTSIDE OF THE MOUNTAINS WOULD EXPECT THE BETTER PCPN CHANCES TO BE GENERALLY TO OUR NORTH AND EAST. COLD FROPA OCCURS ON TUE WITH ECMWF H7 TEMPS AVERAGING AROUND -2 DEG C. WHILE MODELS DIFFER IN TIMING...THERE IS GOOD AGREEMENT IN LLVL UPSLOPE DEVELOPING BY LATE TUE WITH A DECENT QPF SIGNAL ALONG THE FRONT RANGE. MORE WIDESPREAD PCPN IS POSSIBLE MID TO LATE WEEK AS A FRAGMENTED WAVE SLIDES ACROSS THE ROCKIES. WE TRENDED COOLER IN ANTICIPATION OF UPSLOPE-DRIVEN CLOUDS AND PCPN ON TUE NIGHT-THU. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1120 AM MDT THU APR 2 2015 LATEST HRRR GUIDANCE USED FOR THE 18Z TAFS. SHOWING ANOTHER BAND OF SNOW DEVELOPING EARLY THIS AFTERNOON AND PERSISTING THROUGH ROUGHLY 02-03Z THIS EVENING FOR KCYS...KLAR AND KRWL. SOUTHERN PANHANDLE COULD BE IMPACTED LATER THIS AFTERNOON INCLUDING THE AIRPORTS OF KBFF AND KSNY. SNOW THEN EXITS SOUTHEAST WITH VFR CONDITIONS RETURNING. && .FIRE WEATHER... ISSUED AT 420 AM MDT THU APR 2 2015 WETTING PRECIPITATION WITH SNOW WILL OCCUR ALONG THE INTERSTATE 80 CORRIDOR AND ALONG AND WEST OF THE LARAMIE RANGE TODAY. LITTLE TO NO PRECIPITATION WILL OCCUR INTO EAST CENTRAL WYOMING AND THE NORTHERN NEBRASKA PANHANDLE. DRY AND COOL FRIDAY. BREEZY TO WINDY SATURDAY WITH NEAR CRITICAL FIRE CONDITIONS POSSIBLE INTO EAST CENTRAL WYOMING. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR WYZ116. WINTER WEATHER ADVISORY UNTIL 3 AM MDT FRIDAY FOR WYZ114. NE...NONE. && $$ UPDATE...ZF SHORT TERM...SML LONG TERM...CLH AVIATION...GCC FIRE WEATHER...SML