Area Forecast Discussion
Issued by NWS State College, PA

Current Version | Previous Version | Graphics & Text | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KCTP 251801 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 201 PM EDT SAT APR 25 2015 .SYNOPSIS... HIGH PRESSURE TO OUR NORTH WILL KEEP MAINLY DRY CONDITIONS IN PLACE TODAY. LOW PRESSURE MOVING FROM THE MID MISSISSIPPI TO THE CAROLINA COAST WILL BRING THE RISK OF LIGHT RAIN ACROSS SOUTHERN PENNSYLVANIA OVERNIGHT. PERSISTENT UPPER LEVEL TROUGH OVER THE NORTHEASTERN UNITED STATES WILL FAVOR UNSEASONABLY COOL TEMPERATURES THROUGH THE END OF THE MONTH. && .NEAR TERM /THROUGH TONIGHT/... 2 PM UPDATE... DEFORMATION CLOUDS CONTINUE TO STREAK ESE COVERING ABOUT THE SWRN HALF OF THE REGION. REGIONAL RADAR SHOWS AN ELONGATED AREA OF RAIN FROM NRN ILLINOIS ALL THE WAY TO THE MID ATL COAST. THE AREA IS TRANSLATING SLOWLY NORTHEAST WHILE MOVING GENERALLY OFF TO THE EAST. THE STRONG UPPER LOW OVER NEW ENGLAND MAY ACTUALLY WORK OUT TO BE OUR FRIEND...AT LEAST FRIENDLY IN THE RESPECT THAT THE STRONG NW FLOW AROUND THE BACK SIDE OF THE LOW LOOKS LIKE IT WILL WORK TO SQUEEZE THE STORM SYSTEM OVER THE MIDWEST OFF MAINLY SOUTH OF PA. MY FAR SRN ZONES ALONG THE MD BORDER WILL BE THE MOST LIKELY TO SEE PRECIP FROM LATER TODAY INTO SUNDAY MORNING...BUT THE CHANCES FOR RAIN WILL DROP OFF QUICKLY THE FURTHER NORTH ONE GETS IN THE FORECAST AREA. LATEST RUNS OF OUR HIGH RES SHORT RANGE MODELS ALL AGREE WITH THE RAIN REACHING SOMERSET AND BEDFORD COUNTIES AROUND SUNSET...BEFORE SETTLING OFF TO THE SE AGAIN AND BEING SOUTH OF THE REGION BY MIDNIGHT. THE SREF AND GEFS TAKE AN AREA OF LIGHT RAIN A LITTLE FURTHER NORTH...BOTH A LITTLE WETTER/MORE PESSIMISTIC THAN THEIR OPERATIONAL COUNTERPARTS. WITH THE PRECIP TRACKING THROUGH MY SRN ZONES LATE...MODELS DO AGREE THAT JUST ENOUGH COLD AIR COULD BE IN PLACE AFTER MIDNIGHT THAT SOME WET SNOW WOULD BE A POSSIBILITY. BOTH THE SREF AND GEFS THREATS OUTPUT SHOW AS MUCH AS A 30% PROB OF RAIN MIXING WITH SNOW. ACTUAL AMOUNTS ARE NOT EXPECTED TO BE MUCH MORE THAN A COATING...IF THAT MUCH. LOWS FROM THE MID 20S NORTH TO MID 30S SOUTH WILL BE SOME 5-10 DEG BELOW NORMAL. && .SHORT TERM /SUNDAY/... WHILE THE MAIN WAVE OF LOW PRESSURE CURRENTLY OVER THE MIDWEST GETS PINCHED OFF TO OUR SOUTH...UPPER TROUGHING AROUND THE STRONG LOW OVER THE NEW ENGLAND COASTAL WATERS WILL FEED ANY NUMBER OF WEAK SHORTWAVES DOWN AROUND THE ITS BACK SIDE INTO THE REGION FROM THE NORTH. DEEP LAYER MOISTURE WILL BE SPARSE...BUT THE COLD AIR ALOFT AND STRONG APRIL SUN COULD CONSPIRE TO POP OFF SOME LOW TOPPED SHOWERS. THE OPERATIONAL GFS AND ECMWF SHOW SOME LIGHT QPF FOR THE AFTERNOON OVER THE NORTHERN TIER...WHILE THE GEFS AND SREF IMPLY SHOWERS WILL BE A VERY LOW PROBABILITY OCCURRENCE. AT THIS POINT I WILL DOWNPLAY THE CHANCES. IT LOOKS TO REMAIN ON THE UNSEASONABLY CHILLY SIDE DESPITE WHAT SHOULD WORK OUT TO BE A MIX OF SUN AND CLOUDS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... EARLY NEXT WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...THIS LOW FINALLY LIFTS OUT FOR GOOD. BUT DIGGING TROUGH FROM UPPER MIDWEST WILL EXTEND INTO THE SOUTHEAST U.S. BY LATE WEEK...COMBINED WITH A SOUTHERN STREAM SHORTWAVE LIFTING OUT OF THE S PLAINS TOWARD THE E COAST WILL BRING POSSIBILITY OF A DEVELOPING STORM SLIDING NORTHEASTWARD OFF THE EASTERN SEABOARD. TRACK/STRENGTH STILL QUITE UNCERTAIN...BUT AT THIS TIME LOOKS LIKE WE/LL BE BETWEEN THAT LOW PRESSURE AREA AND A HIGH OVER OHIO VALLEY...LIKELY KEEPING CLOUDS AND SCT SHOWERS AROUND AS TEMPS COOL BACK DOWN A BIT. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... WIDESPREAD VFR IS BEING OBSERVED OVER THE FLYING AREA AS MID AND HIGH CLOUDINESS SPREAD ESE FROM A STORM SYSTEM IN THE MIDWEST. LATEST GUIDANCE SUGGESTS JOHNSTOWN/ALTOONA STAND THE BEST CHANCE OF A BRIEF PERIOD OF REDUCED CONDITIONS FROM LATE AFTERNOON THROUGH EARLY TONIGHT AS THE RAIN FROM THE MIDWEST SYSTEM SLIDES OFF TO THE EAST AND CLIPS THE SOUTHERN TIER OF THE FLYING AREA. A LARGE UPPER LEVEL LOW OVER NEW ENGLAND WILL DOMINATE THE REGIONAL WEATHER PATTERN INTO NEXT WEEK WITH SEVERAL SMALL SCALE DISTURBANCES ROTATING AROUND THE WESTERN PERIPHERY OF THE CIRCULATION CENTER. THE PATTERN FAVORS MAINLY VFR CONDITIONS FOR MOST OF THE REGION BUT WITH PASSING RAIN OR EVEN SNOW SHOWERS POSSIBLY CAUSING MVFR OVER THE NORTH AND WEST FOR MONDAY. OUTLOOK... MON...VFR...AREAS OF MVFR WITH RAIN OR SNOW SHOWERS. TUE...IMPROVING CONDITIONS. WED-THU...NO SIG WX. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...ROSS/LA CORTE LONG TERM...LAMBERT/RXR AVIATION...LA CORTE

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