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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
224 PM EDT TUE SEP 1 2015

.SYNOPSIS...
HOT AND HUMID WEATHER WILL CONTINUE THE RECENT SUMMER ENCORE IN
CENTRAL PENNSYLVANIA AS THE CALENDER FLIPS TO SEPTEMBER 2015. THE
PRECIPITATION PATTERN SHOULD BE A MAINLY DRY ONE WITH VERY
ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH THE END OF THE
WEEK.

&&

.NEAR TERM /UNTIL 9 PM THIS EVENING/...
CU ALREADY SHOWING SIGNS OF THINNING AS WE MIX DEEPER AND
INCORPORATE DRIER AIR ALOFT UNDER THE SUPPRESSIVE UPPER RIDGING.
SEE NO REASON TO ADD TO POPS FOR THE NEAR TERM...AS VERY MESO GUID
SHOWS TOTAL LOSS OF INSTABILITY AND ALMOST ALL CLOUDS BEFORE
SUNSET. 

&&

.SHORT TERM /9 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
RIDGING STAYS IN PLACE OVERNIGHT AND WEDNESDAY. MINS TONIGHT
WILL INCORPORATE A HEALTHY DOSE OF PERSISTENCE. EXPECT THEM TO BE
WITHIN A DEG OR TWO OF TUES AM MINS. THE FOG WILL ALSO BE PRESENT
IN THE VALLEYS...BUT THE WIDESPREAD STRATUS IN THE NORTH IS NOT AS
LIKELY TO RECUR. THERE IS A TINY DEPRESSION IN THE OTHERWISE
MASSIVE UPPER LEVEL RIDGE. THE DEPRESSION IS CURRENTLY ASSOCD
WITH A CLUSTER OF STORMS OVER CENTRAL IN. THIS DEPRESSION SHOULD
MOVE EASTWARD THRU THE UPPER OHIO VALLEY AND INTO THE MID ATLANTIC.

BUT THAT FEATURE MAKES ONLY A SMALL DIP IN MID-LVL TEMPS AND TINY
DECREASE IN STABILITY ON WED. THIS MAY BE ENOUGH TO ALLOW SCT
SHRA/TSRA TO DEVELOP IN THE AFTN OVER THE HIGHER TERRAIN...MAINLY
THE LAURELS AND NRN MTNS. THE 30-40 POPS IN THE MTNS WILL PROBABLY
BE THE HIGHEST POPS WE DRAW FOR QUITE A FEW DAYS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
AN ANOMALOUS UPPER LEVEL RIDGE IS FORECAST TO DOMINATE THE LARGE
SCALE PATTERN OVER THE NORTHEASTERN CONUS INTO EARLY NEXT
WEEK...WITH HIGH PRESSURE TAKING CONTROL AT THE SFC. THIS PATTERN
SHOULD SUPPORT ABOVE-NORMAL TEMPERATURES AND VERY LIMITED TO
NO RAINFALL ACROSS CENTRAL PA THROUGH THE LABOR DAY WEEKEND.

THE GFS REMAINS MORE BULLISH VS. THE ECMWF WITH CONVECTION ON
FRIDAY. HIGH PRESSURE INITIALLY CENTERED OVER QUEBEC WILL DROP SWD
OVER THE WEEKEND AND BRING SLIGHTLY COOLER AND DRIER/LESS HUMID AIR
INTO THE REGION. NO RISK OF RAIN AGAIN UNTIL PROBABLY NEXT
TUESDAY AS A COLD FRONT APPROACHES FROM THE GREAT LAKES/OH VLY.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
CU FLAT AND SHOULD BE DISSIPATING SHORTLY - MOST LIKELY BEFORE
SUNSET. FOG IS ALMOST A GIVEN IN THE VALLEYS ONCE AGAIN IN THE
LATE NIGHT/EARLY MORNING. WILL HIT IT HARDEST AT KBFD AND
KIPT...EXPECTING IFR FOR A FEW HRS. OTHERIWSE MVFR FOG/HAZE IS ALL
THAT IS EXPECTED THROUGH 16Z-18Z. A SMALL CHC OF A SHRA EXISTS
OVER THE MTNS ON WED AFTN AS A VERY WEAK DEPRESSION IN THE MASSIVE
UPPER RIDGE SLIDES ACROSS THE UPPER OH VALEY AND MID- ATLANTIC
STATES. HAVE NOT MENTIONED AT THIS RANGE. OTHERWISE...HIGH
PRESSURE IS IN CONTROL THROUGH THE NEXT 5+ DAYS. MORE CLEAR NIGHTS
WITH AM VALLEY FOG AND MOSTLY SUNNY DAYS ARE EXPECTED FOR THE NEXT
FEW DAYS.

OUTLOOK...

THU-SUN...PATCHY AM FOG POSS...MAINLY KIPT/KBFD. OTHERWISE VFR.

&&

.CLIMATE...
PRELIMINARY DATA INDICATES HARRISBURG AND WILLIAMSPORT RECORDED
NEAR-NORMAL TEMPERATURES AND PRECIPITATION FOR THE MONTH OF
AUGUST. MORE DETAILS CAN BE FOUND IN THE MONTHLY CLIMATE
SUMMARIES. SEASONAL SUMMARIES WILL BE AVAILABLE THIS EVENING. 

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...DANGELO
CLIMATE...

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