Area Forecast Discussion
Issued by NWS State College, PA

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 262202 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 602 PM EDT SAT JUL 26 2014 .SYNOPSIS... A SERIES OF DISTURBANCES WILL MOVE ACROSS THE FORECAST AREA THE SECOND HALF OF THIS WEEKEND AS A DEEP UPPER TROUGH DEVELOPS OVER THE NORTHEASTERN UNITED STATES. THERE WILL BE SEVERAL CHANCES FOR PRECIPITATION...INCLUDING STRONG TO POTENTIALLY SEVERE THUNDERSTORMS SUNDAY INTO SUNDAY NIGHT...BEFORE ANOTHER SHOT OF UNSEASONABLY COOL AIR MOVES IN AND REMAINS OVER THE REGION THROUGHOUT THE NEW WORK WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... ACROSS CENTRAL PA...A PRETTY QUIET AFTERNOON ONGOING WITH SCT FLAT CU AS RIDGE SLIDES BY ALOFT. BUT MOISTURE ADVECTING INTO THE OHIO VALLEY ALREADY SPARKING SOME CONVECTION AS IT NOSES TOWARD PA. DID BRING MENTION OF SCT SHOWERS TO NW LATE THIS AFTERNOON...WITH ANOTHER BATCH OF SHOWERS/SCT TSTMS POSS THIS EVE AS SHORTWAVE AND INCREASING MOISTURE BRING A NIGHTTIME SURGE IN INSTABILITY IN FROM THE WEST...WITH STRONGEST STORMS TO SW OF CWA. SHOWERS SHOULD DECREASE AS THEY PASS THE SPINE OF APPALACHIANS OVERNIGHT. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... SUNDAY SHAPING UP TO BE A POTENTIALLY BUSY DAY AS AN UNSEASONABLY STRONG UPPER LOW DROPS THROUGH THE LOWER LAKES AND TAKES AIM AT THE LOCAL AREA. SPC HAS OUTLOOKED REGION JUST TO OUR SW /INCLUDING PORTIONS OF OH-KY-WV/ WITH A MODERATE RISK WHICH LOOKS REASONABLE GIVEN THE STRENGTH OF THE APPROACHING DYNAMICS AND INSTABILITY. WE COULD BE VULNERABLE LOCALLY INTO THE EVENING GIVEN THE EXPECTED TIMING OF THE COLD FRONT ENTERING THE REGION AND THE AMOUNT OF UPSTREAM INSTABILITY/SHEAR THE SYSTEM WILL HAVE AVAILABLE. WHERE THE OHIO VALLEY DEVELOPMENTS TAKE PLACE TONIGHT WILL HAVE MUCH TO SAY ABOUT HOW FAR NORTH INTO CENTRAL PA THE STRONGEST STORMS WILL MANAGE TO MOVE. BUT THIS SYSTEM IS ROBUST ENOUGH THAT WE MAY INITIALLY SEE ONE WAVE OF STORMS DEVELOP ACROSS THE SOUTH DURING THE DAY...WITH A SECOND WAVE DEVELOPING FURTHER NORTH LATE IN THE AFTERNOON INTO THE EVENING. THE SOUTHERN STORMS LOOK TO HAVE THE HIGHEST POTENTIAL FOR LARGE HAIL/DAMAGING WINDS/EVEN AN ISO TORNADO...WITH NORTHERN STORMS MAINLY WIND PRODUCERS. FIRST HALF OF THE EVENING SHOULD STILL BE QUITE BUSY WITH ONGOING STORMS...WITH DECREASING ACTIVITY INTO THE OVERNIGHT BEHIND THE COLD FRONT. && .LONG TERM /MONDAY THROUGH SATURDAY/... RAINFALL WILL DIMINISH IN COVERAGE MONDAY AS THE FRONTAL BOUNDARY MOVES EAST OF THE AREA. LINGERING SHOWERS ARE MOST LIKELY OVER EASTERN PA WITH THE WESTERN CWA DRYING OUT. A DEEP TROUGH OVER THE EASTERN US WILL CONTINUE THROUGH THE UPCOMING WEEK...WITH THE AXIS WAFFLING EAST TO WEST AS INDIVIDUAL SHORT WAVES MOVE THROUGH. ONLY PAINTED ISOLATED SHOWERS IN THE LONG TERM AS SPECIFICS WILL DEPEND ON THE DAY TO DAY LOCATION OF RIPPLES MOVING THROUGH THE TROUGH. WE COULD SEE MORE SIGNIFICANT MOISTURE RETURN NEXT WEEKEND AS THE GFS/GEFS/ECMWF ALL HINT AT THE UPPER TROUGH RETROGRADING A BIT...PAVING THE WAY FOR A SOUTH TO SOUTHEAST FETCH OF ATLANTIC MOISTURE WORKING INTO THE NORTHEAST. 500MB HEIGHTS IN THE 3-4STD DEV BELOW NORMAL RANGE AND 850 TEMPS OF 1-3 STD DEV BELOW NORMAL POINT TO THE MOST CERTAIN PART OF THE FORECAST BEING SEVERAL DAYS OF TEMPERATURES AVERAGING WELL BELOW NORMAL. A SLOW MODERATION CAN BE EXPECTED BY LATE IN THE WEEK. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
VFR CONDITIONS WILL PREVAIL ACROSS THE REGION INTO THE EVENING HOURS AS WEAK RIDGE ALOFT SLIDES THROUGH. TROUGH OF LOW PRES APPROACHING FROM THE GRT LKS WILL LIKELY SPREAD SCT SHRA AND A FEW TSRA INTO CENTRAL PA OVERNIGHT. HOWEVER...MOST PLACES WILL NOT SEE SIG VSBY REDUCTIONS FROM THESE SHOWERS. THE BIGGER CONCERN IS THE POSSIBILITY OF LOW CIGS DEVELOPING TOWARD DAWN AT KBFD...THE RESULT OF LOW LVL MOISTURE ASCENDING THE HIGH TERRAIN OF NW PA. A BAND OF MODERATELY STRONG WINDS ALOFT COULD ALSO PRODUCE MARGINAL LLWS OVERNIGHT...MAINLY OVR THE NW MTNS. ANY EARLY LOW CIGS SHOULD MIX OUT OVR THE N MTNS ON SUNDAY...LEAVING WIDESPREAD VFR CONDS FOR THE REST OF THE DAY. MAIN AVIATION CONCERN WILL COME LATE SUNDAY AND SUNDAY NIGHT...AS A POTENT LOW PRES SYSTEM APPROACHES FROM THE GRT LKS. LATEST MDL DATA POINTS TOWARD THE POSSIBILITY OF SOME STRONG TSRA ACROSS SOUTHERN PA DURING THE LATE AFTN AND EVENING. FURTHER NORTH...THE THREAT OF STRONG WGUSTS IS LOWER. HOWEVER...VSBY REDUCTIONS STILL APPEAR LIKELY IN SHRA/TSRA SUNDAY NIGHT. OUTLOOK... MON...AM LOW CIG POSS W MTNS. TUE-THU...NO SIG WX EXPECTED.
-- End Changed Discussion --
&& .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RXR NEAR TERM...RXR SHORT TERM...RXR LONG TERM...LA CORTE/TYBURSKI AVIATION...FITZGERALD/RXR

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