000 FXUS61 KCTP 140141 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 941 PM EDT TUE MAY 13 2008 .SYNOPSIS... HIGH PRESSURE WILL SETTLE OVERHEAD THIS EVENING. A COLD FRONT WILL MOVE EAST ACROSS THE REGION WEDNESDAY NIGHT AND THURSDAY MORNING. A SERIES OF SYSTEMS WILL THEN CROSS THE REGION FROM WEST TO EAST LATE THIS WEEK AND INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... IR IMAGERY SUGGEST SCT CIRRUS WILL BEGIN SPILLING OVR UPPER LVL RIDGE INTO WESTERN PA LATE TONIGHT. MCLEAR SKIES AND CALM WIND SHOULD ALLOW TEMPS TO BECOME A BIT CHILLY FOR MAY STANDARDS. COLDEST LOCATIONS ACROSS THE N MTNS LIKELY TO DIP INTO THE M30S WITH PATCHY FROST. RETURN SW FLOW ON WEST SIDE OF SFC RIDGE WILL ALLOW WARMER AIR TO FLOW INTO THE REGION ON WED. MODEL 850 TEMPS NR 11C SUGGEST HIGHS WELL INTO THE 70S...DESPITE INCREASING HI CLDS. LATEST SREF AND OPER RUNS INDICATE SHWRS WITH APPROACHING COLD FRONT WILL ARRIVE TOWARD EVENING OVR THE NW MTNS. LATEST MODEL SOUNDINGS SUGGEST GUSTS BTWN 20-25KTS BY AFTN OVR THE NW MTNS...AS PRES GRAD TIGHTENS IN ADVANCE OF FRONT. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/... TIMING DIFFERENCES IN THE OPRNL GUIDANCE...SO WILL KEEP CLOSE TO SREF MEAN TIMING. SCT SHRA WILL MOST LIKELY HOLD OFF UNTIL EARLY EVENING IN THE WEST...AND UNTIL AFTER DARK FOR MOST OF THE REGION. AGAIN...COVERAGE LOOKS SPARSE/SCT FOR THE MOST PART. WILL GO WITH LIKELY POPS IN THE NRN MTNS AND LAURELS FOR THE EVENING...BUT LEAVE THEM CHC OR LESS ELSEWHERE. NOTHING SHOULD REACH THE LOWER SUSQ VALLEY BEFORE DAYBREAK THURS. PRECIP LOOKS REAL LIGHT...IF YOU GET ANYTHING AT ALL. THE FRONTAL BOUNDARY WILL START TO LAY OUT W-E ACROSS THE SOUTHERN TIER ON THURSDAY...WITH DRIER FLOW PUSHING IN FROM THE NORTH CLEARING THE NORTH OUT. WILL HOLD WITH LOW CHC POPS IN THE CENTRAL COS...ENDING FROM N-S THROUGH THE MORNING/EARLY AFTN...WITH ONLY SLIGHT CHCS IN THE SE IN THE AFTN. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... NOT MUCH CHANGE FROM YESTERDAY. DID UP POPS A LITTLE THU NIGHT...AS I HAD LEFT FAR NW PA DRY YESTERDAY. ALSO DID UP POPS ABOUT 10 TO 20 PERCENT ON FRIDAY...AS MODELS TRENDING FURTHER NORTH WITH THE NEXT SYSTEM. ALSO ADDED THUNDER...GIVEN HOW CLOSE LOW TRACKS...AND THE STRENGTH OF THE WARM ADVECTION. GFS BOMBS THE SYSTEM THIS WEEKEND...BUT THINK THIS IS OVERDONE... SO JUST EDGE POPS UP A LITTLE...AND LOWER TEMPS A LITTLE. GFS STILL HAS A SYSTEM MOVING IN FOR MONDAY...AND ANOTHER RIGHT BEHIND THIS...SO LEFT CHC POPS IN...AS GMOS SHOWED DECENT CHC YESTERDAY. WAS THINKING TUE WOULD BE DRY...BUT GMOS AND SOME OF THE MODELS HAVE SOME CHC...SO WENT A LITTLE LOWER THAN GMOS...30 AND 20 PERCENT...BUT DID NOT GO DRY. DID NOT DO MUCH WITH TEMPS DAY 6 AND 7...MAINLY GMOS. GFS WANTS TO DEEPEN SYSTEM NEXT TUESDAY TOO. BOTH SYSTEMS COULD DEEPEN...GIVEN THE PATTERN...AND FROM GRAD SCHOOL... WHEN THERE IS ENERGY IN THE SOUTHERN STREAM...ONE HAS A BETTER CHC TO DO THIS. ALSO MODELS REALLY WANT TO CRANK UP HUGE WEST COAST RIDGE. NOT MUCH CHANGE LIKELY UNTIL BLOCKING PATTERN GOES. PERHAPS MOTHER NATURE IS TRYING TO GO OPPOSITE LAST YEAR...AS SE AND MID ATLANTIC HAS BEEN STORMY LATELY. && .AVIATION /01Z WEDNESDAY THROUGH SUNDAY/... HIGH PRESSURE WILL SETTLE OVERHEAD THIS EVENING AND A WEAKENING COLD FRONT WILL PASS THROUGH FROM WEST TO EAST WED NIGHT AND THURS MORNING. THE LIGHT N/NW WINDS WILL GO CALM TONIGHT...AND INCREASE OUT OF THE SOUTH WED MORNING...AND MAY GUST UP TO 20 KTS WED AFTN. MUCH OF WED WILL BE DRY...BUT SCT SHOWERS WILL OCCUR OVER THE WESTERN LOCATIONS BY LATE WED AFTN AND SLIDE EAST WED EVENING/NIGHT. THE COVERAGE SHOULD REMAIN SCT FOR THE MOST PART. PRECIP WILL BE LIGHT AND CIGS HIGH AND ANY REDUCTIONS IN VSBYS/CIGS WILL BE BRIEF...AS IT MAY STAY VFR AT MANY TERMINALS. THURSDAY IS NOT LOOKING BAD AT THIS POINT...BUT MORE UNSETTLED WEATHER IS IN STORE FOR FRIDAY AND INTO THE WEEKEND. && .FIRE WEATHER... WHILE WED WILL FEATURE LOW RH VALUES AND AN INCREASING BREEZE... RH VALUES WILL STILL BE A LITTLE ABOVE 30 PERCENT...AND RECENT WET WEATHER SHOULD HELP FUEL MOISTURE LEVELS STAY UP HIGHER THAN WHAT WE HAD DURING OUR DRY SPELL BACK IN MID APRIL. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO NEAR TERM...FITZGERALD SHORT TERM...DANGELO LONG TERM...MARTIN AVIATION...DANGELO/GARTNER FIRE WEATHER...MARTIN/GARTNER