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 031040 AFDCTP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 640 AM EDT SUN MAY 3 2015 .SYNOPSIS... HIGH PRESSURE OVER THE SOUTHERN APPALACHIANS WILL DRIFT EAST AND OFF THE CAROLINA COAST TONIGHT. A DEVELOPING SOUTHWESTERLY FLOW WILL LEAD TO WARMER TEMPERATURES THAT WILL CONTINUE THROUGH AT LEAST THE MIDDLE OF THE UPCOMING WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 11-3.9 IR SATL LOOP AND SFC OBS INDICATING JUST SOME PATCHES OF MID LEVEL AC CLOUDS ROAMING ABOUT THE AREA EARLY THIS MORNING. A RIDGE OF HIGH PRESSURE EXTENDING NORTH/SOUTH ACROSS THE SUSQ VALLEY WAS PROVIDING VERY LIGHT AND VARIABLE WIND...AND DRY DEWPOINTS LEADING TO STRONG RADIATIONAL COOLING OF THE AIR NEAR THE GROUND. MESO OBS SHOW TEMPS HAVE PLUMMETED WELL INTO THE 30S THROUGHOUT THE NORMALLY COLD VALLEYS UP NORTH. COUDERSPORT IN CENTRAL POTTER COUNTY TAKE THE PRIZE FOR THE ICE BOX SO FAR THIS MORNING WITH A TEMP OF 30F AT 0815Z. READINGS IN THE 40S TO LOWER 50S WERE COMMON THROUGHOUT MOST OF THE REST OF CENTRAL PENN AND THE SUSQ VALLEY. TEMPS WILL FALL ANOTHER 2 OR 3 DEG F OVER THE NEXT FEW HOURS WITH MINS AT SUNRISE VARYING FROM THE LOW-MID 30S ACROSS THE NW MTNS...TO 45-50F IN THE LOWER SUSQ VALLEY. THE COLDEST SPOTS IN THE NORTH SHOULD DIP TO ABOUT 28F WITH FROST. PATCHY FOG AND AREAS OF LOW CLOUDS ARE POSSIBLE FOR A FEW HOURS AROUND DAYBREAK ACROSS LANCASTER CO...WHERE MDLS POOL LL MOISTURE IN VICINITY OF OLD SFC TROF. FOR THE REST OF TODAY...NICE EARLY MAY WEATHER IS ON TAP. ASIDE FROM SOME PATCHY HIGH BASED CU OR ALTO CU...AND SOME THIN CIRRUS...CONDITIONS WILL BE MOSTLY SUNNY TO SUNNY. HIGH TEMPS THIS AFTERNOON WILL BE SIMILAR...IF NOT A DEG OR TWO F WARMER THAN SATURDAY...RANGING FROM AROUND 70 ACROSS THE NORTHERN MTNS...TO BETWEEN 74 AND 78F IN THE SOUTHERN VALLEYS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... DEEPENING...THOUGH STILL RELATIVELY WEAK SWRLY FLOW WILL LEAD TO JUST SOME PATCHY HIGH BASED STRATO CU AND ALTO CU CLOUDS WITH VERY LIGHT SFC WIND. TEMPS SHOULD BE ABOUT 5 DEG F MILDER EARLY MONDAY COMPARED TO SUNRISE SUNDAY. STILL...A FEW MID TO UPPER 30S SHOULD BE SCATTERED ABOUT THE COLD SPOTS OF THE NORTHERN MTNS. MONDAY WILL FEATURE MORNING SUNSHINE FOLLOWED BY SCT-BKN AFTERNOON CU. ANY CHC FOR SHRA/TSRA SHOULD BE ACROSS THE NW MTNS AND LIMITED TO LATE IN THE AFTERNOON AND EVENING AS A COLD FRONT SAGS SE FROM THE GLAKES. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... SHORTWAVES TRACKING EAST ACROSS SOUTHERN CANADA TO NORTH OF THE GREAT LAKES WILL HELP PUSH A BACKDOOR-STYLE SFC COLD FRONT INTO CENTRAL OR SRN PA BY EARLY TUESDAY. THE FRONT WILL WAVER NEAR OR MORE LIKELY JUST TO THE SOUTH OF THE MASON-DIXON LINE INTO THE MIDDLE OF THE UPCOMING WEEK...AND WILL SERVE AS A FOCUS FOR CLOUDS AND SHOWERS MAINLY ALONG AND NORTH OF THE BOUNDARY. THE LATEST ENSEMBLE DATA SHOWS ABOVE NORMAL PWS ALONG THE E-W FRONTAL ZONE WHICH IS USUALLY A GOOD INDICATOR OF AT LEAST CLIMO OR BETTER POPS BUT DUE TO THE N-S MDL QPF DIFFERENCES WILL UTILIZE A BLEND AND CAP POPS AROUND THE HIGH CHC LEVEL /40-50 PCT/ FOR DAYS 3-4. FROM THE MIDDLE TO LATER PART OF THE WEEK...THE GLOBAL NUMERICAL MODEL AND ENSEMBLE GUIDANCE SHOWS LOW PRESSURE MOVING EAST FROM THE NORTHERN HIGH PLAINS TO THE WESTERN GREAT LAKES/UPPER MIDWEST BY FRIDAY. THIS SHOULD ALLOW THE WRN PORTION OF THE E-W FRONTAL ZONE TO BE LIFT NWD THROUGH THE OH VLY WHILE THE ERN SEGMENT WEAKENS AND WAVERS JUST WEST/SOUTH OF THE PA AND OH/WV/MD BORDERS. IN GENERAL THE PCPN PATTERN SHOULD BE MORE SUMMER-LIKE WITH WEAK FORCING UNDER HIGH HEIGHTS ALOFT AND SCT DIURNAL SHOWER/ISOLD TSTM ACTIVITY NEAR THE BNDRY AND PERHAPS INITIATING OVER THE WRN HIGH TERRAIN. THEREFORE KEPT POPS IN THE SCHC TO LOW CHC RANGE WED-FRI WITH GRADUAL INCREASE INTO THE WEEKEND AS THE PLAINS FRONTAL SYSTEM APPROACHES. TEMPERATURES SHOULD AVG NEAR TO ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... NO BIG CHANGES NEEDED FOR THE 12Z TAF PACKAGE. ONLY A FEW MID LVL CLDS TO THE EAST. EXPECT VFR CONDITIONS TODAY...WITH RATHER LIGHT WINDS FOR THIS TIME OF YEAR. A TASTE OF FINE SPRING WEATHER. AN APPROACHING COLD FRONT MAY TRIGGER SOME SHOWERS ACROSS NORTH CENTRAL PA ON TUESDAY. THE FRONT WILL LIKELY SLOW AND CREATE LOW CIGS/SHOWERS AGAIN ON WED. THE FRONT MAY PUSH TO THE SOUTH ON THURS. OUTLOOK... TUE...VFR EARLY...THEN SHRA IN THE NORTH. WED-THU...MORE SHOWERS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...LAMBERT/STEINBUGL AVIATION...DANGELO/MARTIN

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