Area Forecast Discussion
Issued by NWS State College, PA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KCTP 050904 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 504 AM EDT SAT SEP 5 2015 .SYNOPSIS... HIGH PRESSURE WILL ENSURE MAINLY DRY WEATHER FOR LABOR DAY WEEKEND WITH ABOVE NORMAL WARMTH AND JUST THE CHANCE OF AN AFTERNOON OR EVENING POP-UP SHOWER OR THUNDERSTORM. THE PATTERN WILL START TO CHANGE IN THE MIDDLE OF THE WEEK AS THE UPPER LEVEL FLOW FLATTENS OUT AND A COLD FRONT DROPS DOWN FROM THE NORTH. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SHOWERS HAVE BEEN PERSISTENT IN THE SRN TIER THROUGH THE NIGHT. THE WIND SHIFT/WEAK CONVERGENCE AND DEEP EASTERLY MOISTURE INFLUX ARE PROBABLY DRIVING THESE SHOWERS SINCE DIURNAL INSTABILITY HAS LONG SINCE DISAPPEARED. ONLY LIGHT SHOWERS /NO T/ LEFT IN THE SC MTNS. HRRR AND RAP MOVE THESE SLIGHTLY TO THE WEST BEFORE KILLING THEM OFF JUST AFTER SUNRISE. LOW CLOUDS HAVE OVERSPREAD/DEVELOPED OVER THE ENTIRE REGION EXCEPT FOR WARREN CO. A FEW PATCHES OF CLEAR EAST OF KIPT CAN BE IMAGINED WHEN PERUSING THE 11-3.9 MICRON IMAGERY THIS MORNING. OTHERWISE...IT IS CLOUDY. THESE CLOUDS COULD BE TOUGH TO MIX OUT - AT LEAST IN A RAPID FASHION - SINCE THEY ARE GENERALLY ABOVE 1KFT. THUS...WILL HANG ONTO SOME OF THESE CLOUDS INTO THE MID TO LATE MORNING. THE EAST WILL BE BREAKING OUT INTO THE SUN AND THE MIXING IN THE WEST COULD ALLOW A SHOWER OR TWO TO DEVELOP IN THE AFTN. HOWEVER...MOST OF THESE WILL REMAIN WEST OF THE CWA. ONLY THE NW IS WORTHY OF A CHC POP FOR LATE THIS AFTN/THIS EVENING AS A LAKE BREEZE MAY KICK OFF A FEW SHRA. THE CLOUDS WILL MAKE IT MORE DIFFICULT TO GET TO THE LOFTY MAXES WE HAVE EXPERIENCED RECENTLY - INCLUDING TIES OF THE RECORD HIGHS AT HARRISBURG...ALTOONA AND BRADFORD YESTERDAY. WILL GO FOR MAXES BASED ON AN EQUAL BLEND OF MOS GUIDANCE MINUS ONE OR TWO DEGS. THIS WILL RESULT IN ONLY A 10 DEGREE DIURNAL SWING AT MANY PLACES. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... THE UPPER LOW OVER THE UPPER GREAT LAKES WILL SLOLY FILL AND LOSE CHARACTER. THE SFC HIGH WILL STILL NOSE INTO THE STATE...BUT THE CENTER OF IT WILL SLIDE SOUTH INTO THE WESTERN ATLANTIC BY MONDAY. ANY SHOWERS THIS EVENING WILL LIKELY BE IN THE NW...BUT THE EXPECTED CELL MOTION SHOULD KEEP THEM EITHER OUT OF THE STATE TO THE NORTH OR MAKE THE FEW THAT DO POP UP GO SLOWLY TO THE NORTH AND OUT OF THE AREA EARLY THIS EVENING. THE LOW CLOUDS WILL PROBABLY TRY TO REDEVELOP IN THE ERN MTNS. OTHER AREAS MAY SEE THEM TRY TO FORM...BUT WILL KEEP IT GENERALLY P/C OVERNIGHT WITH THE CLEARING PERHAPS ALLOWING FOR SOME MORNING FOG ON SUNDAY. SUNDAY LOOKS TO BE DRIER AND SUNNIER...AND POPS ALMOST NON- EXISTENT. TEMPS WILL GET A FEW DEGS F WARMER VS SATURDAY. ONCE AGAIN...IT WILL BE THE FAR NW WHICH COULD SEE A POP UP SHOWER - PERHAPS AGAIN BEING GENERATED ALONG A LAKE BREEZE BOUNDARY. && .LONG TERM /MONDAY THROUGH FRIDAY/... THE HIGH PRESSURE WILL KEEP IT WARM AND MAINLY DRY INTO MONDAY. A WEAK COLD FRONT WILL SLIDE SLOWLY TO THE ESE FROM THE GREAT LAKES/MIDWEST STATES. THIS FEATURE COULD BRING SOME ISOLATED SHRA/TSRA TO OUR NW ZONES BEGINNING TUESDAY AFTERNOON AND EVENING. A SLOWLY AMPLIFYING BROAD TROUGH FROM THE NRN PLAINS THROUGH THE NE U.S. WEDNESDAY AFTERNOON INTO NEXT WEEKEND WILL PUSH A SECOND...STRONGER CFRONT EAST ACROSS THE COMMONWEALTH WEDNESDAY NIGHT AND THURSDAY. THIS PATTERN TRANSITION WILL BRING A FEW OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS...ALBEIT MAINLY OF THE SCATTERED AFTERNOON AND EVENING VARIETY. 12Z GEFS AND 12Z EC ARE IN GOOD AGREEMENT ON THE LOCATION OF THIS TROUGH AXIS /FROM LAKE SUPERIOR TO THE MID MISS VALLEY AT 00Z SAT/...THOUGH AS ONE WOULD EXPECT...THE ENSEMBLE MEAN DAMPENS OUT THE AMPLITUDE OF THE TROUGH COMPARED TO THE EC. DETAILS IN THE TIMING OF ANY SPECIFIC SHORTWAVES ROTATING THROUGH THIS AMPLIFYING TROUGH ARE SIMPLY TOO MUDDY AT THIS TIME RANGE. ONE THING MORE CERTAIN IN THIS MEDIUM RANGE FORECAST IS THE COOLING TEMPS FOR THE LATTER HALF OF THE WEEK AND NEXT WEEKEND...WHEN BOTH MAX AND MIN TEMPS COULD BE UP TO SEVERAL DEG F BELOW NORMAL /ESPECIALLY OVER THE NRN AND WESTERN MTNS OF THE STATE...WHERE MORE CLOUDS AND COOLER TEMPS ALOFT WILL BE FOUND/. && .AVIATION /09Z SATURDAY THROUGH WEDNESDAY/... 11.3.9U IMAGERY AT 09Z SHOWS STRATUS HAS BECOME WIDESPREAD ACROSS CENTRAL PA...THE RESULT OF MOIST SERLY FLOW AND OROGRAPHIC LIFTING. BLEND OF LATEST HRRR/SFC OBS SUGGEST IFR CIGS ARE LIKELY BTWN 09Z-13Z AT KBFD/KJST/KAOO AND POSSIBLE AT KUNV. LOWER ELEVATIONS FURTHER EAST SHOULD FARE BETTER WITH MVFR CIGS EXPECTED. WILL HAVE TO WATCH FOR POSSIBILITY OF FOG DEVELOPMENT AT KLNS ARND DAWN. SOME MDL DATA SUGGESTS SKIES WILL CLEAR ACROSS THAT PART OF THE STATE ARND 10Z...ALLOWING FOR DEVELOPMENT OF RADIATION FOG BTWN 10Z-13Z. DIURNAL HEATING/MIXING WILL CAUSE CIGS TO RISE BY LATE AM. MDL SOUNDINGS INDICATE MVFR CIGS MAY LINGER ACROSS THE CENTRAL MTNS UNTIL ARND NOON. HOWEVER...BY AFTN THERE IS A HIGH DEGREE OF CONFIDENCE IN WIDESPREAD VFR CONDS AND LIGHT WIND. MOSTLY CLEAR SKIES AND A LIGHT WIND WILL LIKELY RESULT IN PATCHY VALLEY FOG AGAIN EARLY SUNDAY MORNING. OUTLOOK... SUN-TUE...PATCHY FOG IN THE MORNING...OTHERWISE VFR. WED...ISOLD PM TSRA IMPACTS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO NEAR TERM...DANGELO SHORT TERM...DANGELO LONG TERM...LAMBERT AVIATION...FITZGERALD

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.