000 FXUS61 KCTP 121527 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 1127 AM EDT SUN OCT 12 2008 .SYNOPSIS... A LARGE AREA OF HIGH PRESSURE WILL HOLD IN PLACE FROM NEW ENGLAND TO THE MID ATLANTIC COAST THROUGH EARLY IN THE COMING WEEK... RESULTING IN WARM SUNNY DAYS AND COOL NIGHTS. A COLD FRONT WILL MOVE ACROSS THE AREA MID-WEEK...BRINGING A CHANCE OF SHOWERS. NEAR TO BELOW NORMAL TEMPERATURES AND FAIR WEATHER ARE FORECAST BY THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... RIVER VALLEY FOG HAS DISSIPATED AND WE`LL BE TREATED TO ANOTHER SUNNY...WARM AUTUMN DAY WITH LIGHT AND VARIABLE WINDS. HIGH TEMPERATURES IN THE MID TO UPPER 70S WILL BE AROUND 10-12F ABOVE NORMAL IN THE CENTRAL AND SOUTHERN VALLEYS...AND AS MUCH AS 15F ABOVE NORMAL ACROSS THE NRN AND WRN MTNS OF PENN. ENJOY! && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... WITH NO SIG CHANGE IN THE UPPER OR SFC PATTERN...EXPECT CONTINUED CLEAR SKIES AND LIGHT WINDS FOR MUCH OF TONIGHT...FOLLOWED BY A SUNNY DAY ON MONDAY. WILL LIKELY BE EMPHASIZING THE VALLEY FOG MORE WITH THIS AFTERNOON`S GRIDS/ZONE PACKAGE...AS SLIGHTLY HIGHER SFC DEWPOINTS WILL COMBINE WITH CLEAR SKIES AND LIGHT WINDS TO BRING RATHER EXTENSIVE (AND AT TIMES DENSE) VALLEY FOG FROM 10-13Z MONDAY. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... HIGH PRESSURE SURFACE AND ALOFT WILL CONTINUE ABOVE NORMAL TEMPERATURES EARLY THIS COMING WEEK. MODELS SUGGEST A CLD FRONT WILL PROGRESS THROUGH THE EXTREME NORTHEAST/NEW ENGLAND REGION MONDAY AND POSSIBLY INTO THE MID ATLC AS A WEAK BACKDOOR FNT...BEFORE RETREATING NEWD ON TUE. MAIN IMPACT LOCALLY WOULD BE ON TEMPS...BUT THE EC/GFS BOTH KEEP THE FNT WELL TO THE NORTH/EAST. THE HIGH AMPLITUDE H5 RIDGE AXIS SHOULD BEGIN TO FLATTEN INTO MID- WEEK AS SHORT WAVE ENERGY EJECTS FROM THE DEEP TROF OVR THE ROCKIES. HPC HAD NOTED SOME MAJOR DIFFS REGARDING THIS SYS APPROACHING THE UPR GRT LKS...AS WELL AS RESIDUAL ENERGY THAT MAY FOLLOW. HOWEVER...AT THIS TIME IT APPEARS THE OPERATIONAL GFS/EC ALONG WITH THE GEFS ARE BEGINNING TO CONVERGE ON A CONSENSUS SOLUTION INVOLVING TWO CLD FNTS. THE FIRST/TRAILING CLD FNT ASSOC WITH THE LEAD S/W WOULD WEAKEN AND BECOME Q-STNRY INVOF OF NRN PA TUE/TUE NGT. THE SECOND...STRONGER AND MORE PROGRESSIVE CLD FNT ASSOC WITH THE REMAINING/SHEARING ENERGY FROM THE ROCKIES TROF WOULD CROSS THE REGION ON THUR. USED A BLEND OF GMOS/HPC POPS TO ACCOUNT FOR TIMING/UNCERTAINTY. THE MEAN FLOW PATTERN ALOFT BRIEFLY TRANSITIONS TO ZONAL AS THE EARLY WEEK UPR RIDGE SINKS SWD INTO THE SRN U.S. MODELS AND ENSEMBLES ARE NOW FAVORING A COOLER REGIME FOR LATE IN THE WEEK AND INTO THE WEEKEND. CONSIDERABLE UNCERTAINTY/SPREAD IS NOTED IN THE GEFS CONCERNING THE DEPTH AND POSITION OF TROFING IN THE EAST...AND THIS IS EVIDENCED BY THE DIFFS IN THE OPERATIONAL GFS VS. THE EC. REGARDLESS...TEMPERATURES ARE FCST TO RETURN TO CLIMO VALUES AND POSSIBLY BLW NORMAL BY NEXT WEEKEND ESPECIALLY IF THE EURO SOLN VERIFIES. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... PATCHY MVFR AND LOCALIZED IFR CONDITIONS THIS MORNING IN FOG. VFR CONDITIONS EXPECTED BY 13-14Z IN ALL AREAS...WITH MAINLY CLEAR SKIES. EXPECT SOME PATCHY FOG FORMATION OVERNIGHT AGAIN TONIGHT...BUT MAYBE A BIT LESS WIDESPREAD...SO ATTM HAVE NOT INCLUDED IN MOST TAFS EXCEPT FOR IPT. VFR CIGS/VSBYS SHUD DOMINATE THE NEXT SEVERAL DAYS...HOWEVER MAY BE DEALING WITH AT LEAST PATCHY AM FOG. UPPER LEVEL RIDGE BEGINS TO RELAX MID-WEEK AND ALLOW A FRONTAL BOUNDARY TO SLIDE EAST TOWARDS CENTRAL PA. MOISTURE APPEARS TO BE STARVED FROM MID-WEEK SYSTEM...HOWEVER CAN/T RULE OUT A CHC FOR A PERIOD OF MVFR CIGS/VSBYS LATE TUE/WED BEFORE RETURNING TO SOLID VFR THUR/FRI. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...GARTNER NEAR TERM...LAMBERT SHORT TERM...LAMBERT/GARTNER LONG TERM...STEINBUGL AVIATION...JUNG/LAMBERT