642 FXUS61 KCTP 190324 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 1124 PM EDT MON MAR 18 2013 .SYNOPSIS... A COMPLEX STORM AND FRONTAL SYSTEM WILL TRACK ACROSS THE AREA TONIGHT. A SECONDARY LOW WILL DEVELOP SOUTHEAST OF THE STATE ACROSS THE DELMARVA REGION AND MOVE OFF THE COAST TUESDAY. A COLD NORTHWEST FLOW PATTERN WILL PERSIST THROUGH THE REMAINDER OF THIS WEEK. HIGH LATITUDE BLOCKING WILL KEEP AN UPPER TROUGH OVER THE EASTERN U.S. FOR THE FORESEEABLE FUTURE...WITH BELOW NORMAL TEMPERATURES LIKELY CONTINUING INTO THE END OF THE MONTH. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... RADAR AND SFC OBS INDICATE PRECIP HAS CHANGED FROM FROZEN TO LIQUID OVER ALL BUT THE NORTHEAST QUARTER OF THE STATE AT 02Z... ROUGHLY FROM IPT NORTH AND EAST. LITTLE ADDITIONAL SNOW IS EXPECTED EVEN IN THIS AREA...AS PUSH OF WARM AIR ALOFT WITH APPROACHING LL JET SHOULD CAUSE EVEN THE MTNS NE OF IPT TO CHANGEOVER BY ARND 03Z. FOR MOST OF CENTRAL PA...THE MAIN FCST ISSUE FOR THE REST OF THE NIGHT WILL BE RAIN VS FZRA. ALTHOUGH STRONGEST FGEN FORCING AND ASSOCIATED HEAVIEST PRECIP IS SHIFTING NORTH OF THE REGION AT 02Z...WAA AND A MOIST SERLY FLOW INTO THE APPALACHIANS WILL SUPPORT LIGHTER PRECIP OVERNIGHT. WHERE TEMPS REMAIN BLW 0C...A DECENT COATING OF ICE REMAIN POSSIBLE ACROSS THE HIGHER TERRAIN OF CENTRAL AND NORTH CENTRAL PA. 18Z MDL QPF SUGGESTS UP TO A QUARTER INCH OF ICE IS POSSIBLE OVR THE MTNS N OF I-80. ACROSS THE LOWER SUSQ VALLEY...TEMPS CURRENTLY ARND THE FREEZING MARK AND WARMING SFC TEMPS EXPECTED OVERNIGHT...SO AN EARLY CANCELLATION OF THE ADVISORY MAY BE POSSIBLE DOWN THERE. ELSEWHERE...LATEST HI-RES MDL DATA INDICATES AT LEAST POCKETS OF SUB-FREEZING AIR REMAIN OVR THE NORTH CENTRAL MTNS THRU EARLY TUE AM. ACROSS THE LAUREL HIGHLANDS COLD AIR IS EXPECTED TO BE SCOURED OUT ARND OR SHORTLY AFTER MIDNIGHT. HOWEVER...BASED ON CURRENT TEMPS...MAY NEED TO EXTEND THE WARNING THERE A BIT PAST MIDNIGHT. PASSAGE OF OCCLUSION LATE TONIGHT WILL BE ACCOMPANIED BY MARGINAL INSTABILITY AND STRONG LG SCALE FORCING AHEAD OF UPPER LVL SHORTWAVE...SO CAN/T RULE OUT A TSRA IN SOME PARTS OF SOUTHERN PA. BEHIND THE OCCLUSION IT WILL COOL ALOFT ONCE AGAIN AND ANY LIGHT LINGERING RAIN/FZRA COULD CHANGE BACK TO SNOW SHOWERS OVR NORTHERN AND WESTERN MTNS NR DAWN. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... THE COMPLEX SYSTEM WILL BE MOVING EAST OF THE AREA BY EARLY TUESDAY AND WILL TRANSITION INTO A NEW SECONDARY SURFACE LOW ALONG THE NJ COAST DURING THE DAY. THIS WILL USHER IN SOME BRIEF IMPROVEMENT FOR THE MIDDAY AND AFTERNOON HOURS OVER CENTRAL AND EASTERN AREAS. HOWEVER...STRONG AND DEEP COLD AIR ADVECTION WILL HELP TO MAINTAIN PLENTY OF CLOUDS ALONG WITH SCATTERED SNOW SHOWERS ACROSS THE HIGHER TERRAIN OF THE NORTH AND WEST THROUGHOUT THE DAY. MORE NOTABLE MAY BE THE INCREASING WESTERLY WIND...WHICH SHOULD GUST BETWEEN 25-35 MPH DURING THE AFTERNOON. HIGHS RANGING FROM THE L30S OVER THE NW...TO NEAR 50 IN THE SE WILL BE SOME 5 TO 15 DEG BELOW NORMAL FOR THE LAST DAYS IF THE ASTRONOMICAL WINTER. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... AGAIN TODAY...THE LONG TERM PERIOD LOOKS TO BE DOMINATED BY BROAD UPPER TROFFING OVER NORTHEASTERN NORTH AMERICA WITH FAST...GENERALLY ZONAL FLOW ACROSS THE SRN U.S. BELOW NORMAL TEMPERATURES ARE EXPECTED TO DOMINATE AS A RESULT. THE LONGWAVE PATTERN IS FORECAST TO REMAIN HIGHLY ENERGETIC...BUT AGAIN THROUGH THIS FORECAST PERIOD...NO SIGNIFICANT STORM DEVELOPMENT IS EXPECTED TO AFFECT THE NORTHEASTERN U.S. OUTSIDE OF THE CURRENT SYSTEM AFFECTING PA. WIDESPREAD SNOW SHOWERS ARE EXPECTED TUESDAY AS THE CURRENT STORM SYSTEM EXITS. SNOW/RAIN SHOWERS WILL BECOME MORE SCATTERED WEDNESDAY INTO THURSDAY...AFFECTING MOSTLY THE MAIN LAKE EFFECT REGIONS ON PERSISTING NWRLY FLOW. WIND FLOW IS FORECAST TO BECOME MORE NRLY BY FRI FURTHER REDUCING COVERAGE OF ANY LINGERING SHOWERS. THE NEXT POTENTIAL STORM SYSTEM IS A SOUTHERN STREAM WAVE IN THE GFS AND EC...MOVING ACROSS THE NORTHERN GULF COAST NEXT WEEKEND. TRACK OF THIS SYSTEM AT THIS SYSTEM WILL KEEP ANY SENSIBLE WEATHER AFFECTS FAR FROM PA. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... BEEN DOING UPDATES AS NEEDED THIS EVENING. SOME FREEZING RAIN AND SLEET ACROSS MUCH OF THE AREA...WHILE DRIZZLE AND FREEZING DRIZZLE ACROSS THE SOUTH AND EAST. EARLIER DISCUSSION BELOW. MIXED AREA OF SNOW STILL TO THE EAST...BUT THAT WILL BE EAST OF OUR AREA SHORTLY. RADAR SHOWS MORE PRECIPITATION TO THE WEST...BUT RADAR RETURNS AND OBS INDICATE THIS IS MORE OF A MIX OF SLEET...SNOW...AND FREEZING RAIN. THUS HAVE MIX IN MOST OF THE TAFS. FOR THE SE... JUST WENT WITH FOG BY LATE EVENING...AS PRECIPITATION MAY JUST CUT OFF BY THEN. HARD TO SEE THINGS WARMING UP MUCH OVERNIGHT...AS WINDS WEAKEN... AND COASTAL LOW TAKES OVER. THE COMPLEX LOW/FRONTAL SYSTEM IS EXPECTED TO SOLIDIFY INTO A SINGLE LOW OFF THE NJ COAST BY EARLY TUESDAY...WITH THE LOCAL AREA COMING UNDER THE INFLUENCE OF DEEP-COLD AND GUSTY NW FLOW. WESTERN TERMINALS WILL LIKELY REMAIN MVFR WITH SNOW SHOWERS...WHILE CENTRAL AND EASTERN AREAS WILL IMPROVE TO VFR. OUTLOOK... WED-SAT...GUSTY WEST TO NW FLOW. MVFR WITH OCNL -SHSN WEST. MAINLY VFR SE. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 8 AM EDT TUESDAY FOR PAZ005-006- 010>012-017>019-025-026-034-035-037-041-042-045-046. WINTER WEATHER ADVISORY UNTIL 8 AM EDT TUESDAY FOR PAZ004-027- 028-036-049>053-056>059-063>066. WINTER STORM WARNING UNTIL 5 AM EDT TUESDAY FOR PAZ024-033. && $$ SYNOPSIS...LA CORTE NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD/LA CORTE LONG TERM...CERU/GARTNER AVIATION...MARTIN