Area Forecast Discussion
Issued by NWS State College, PA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
000
FXUS61 KCTP 170339
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1139 PM EDT TUE SEP 16 2014

.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE MIDWEST TONIGHT. A STRING OF
MOSTLY SUNNY DAYS AND CHILLY NIGHTS WILL FOLLOW FOR THE REST OF
THE WEEK. TEMPERATURES WILL BE SLIGHTLY BELOW NORMAL ALL WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
DIURNAL CUMULUS DISSIPATED EARLIER THIS EVENING...BUT H5 SHEAR
AXIS CENTERED FROM WEST TO EAST ACROSS CENTRAL PA IS MAINTAINING
SCT TO LOCALLY BKN STRATUS FROM EAST CENTRAL OHIO THROUGH MIDDLE
SUSQ RIVER VALLEY...AND EXPECT THIS TO PERSIST FOR SEVERAL MORE
HOURS.

IR IMAGERY SHOWS BEST ADVECTION OF LAKE MOISTURE INTO THE
FINGERLAKES REGION AT THIS HOUR...BUT SOME OF THIS MAY MAKE A RUN
INTO THE NORTHWEST MOUNTAINS OVERNIGHT...PERHAPS KEEPING SCT
COVERAGE OF CLOUDS IN THE NORTHWEST. ELSEWHERE...LOWERING
DEWPOINTS...FAVORABLE RADIATIONAL COOLING...AND CALM WIND WILL
ALLOW FOR EFFICIENT TEMPERATURE FALLS THROUGHOUT.

PREVIOUS CONSENSUS MAINTAINED FOR ONLY A MENTION PATCHY FROST IN
THE NORTHERN MOUNTAINS TONIGHT/WED AM DUE TO CLOUD UNCERTAINTY.
RIVER VALLEY FOG WILL ALSO FORM...ALSO WORKING AGAINST A
WIDESPREAD FROST.

MINS STILL EXPECTED TO RANGE FROM THE MID TO UPPER 30S NORTH TO
THE LOWER TO MIDDLE 40S SOUTHEAST.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
HIGH PRESSURE PRETTY MUCH OVERHEAD ON WED. DIURNAL CU ARE EXPECTED
AFTER THE MORNING VALLEY FOG LIFTS AND COOL AIR ALOFT LEADS TO
SOME LIMITED INSTABILITY. ON THE WHOLE...A REALLY NICE DAY. TEMPS
SHOULD GET BACK INTO THE LOWER 60S ON THE HIGHEST OF ELEVATIONS OF
THE NW AND MID 70S IN THE LOWEST/URBAN LOCATIONS IN THE SE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
UPPER TROUGH SHARPENS OVER QUEBEC WED NIGHT/THU AS A SHORTWAVE
SLIDES THROUGH...PUSHING A WEAK FRONTAL BOUNDARY SOUTH TOWARD PA
ON THU. THIS FRONT WILL CONTINUE TO WEAKEN AS IT EDGES
SOUTHWARD...BUT ANOTHER SHORTWAVE WILL SLIDE OVERHEAD FROM THE
MIDWEST ON THU. THIS WILL BRING AN INCREASE IN MID LEVEL
INSTABILITY AND THUS A MORE ROBUST CLOUD FIELD ALONG WITH JUST A
CHANCE FOR A SPRINKLE. NORTHERN PA WILL GET A REINFORCING SHOT OF
COOLER AIR...KEEPING HIGHS IN THE UPPER 50S TO LOWER 60S.

BROAD RIDGE OVER CENTRAL U.S. FLATTENS AS IT WORKS EAST...WITH A
STRENGTHENING BUBBLE OF SURFACE HIGH PRESSURE BUILDING ACROSS THE
GREAT LAKES INTO A 1030MB HIGH OVER NEW ENGLAND BY FRI...BRINGING
A PERIOD OF QUIET WEATHER AND UNSEASONABLY COOL TEMPERATURES.
MORNING LOWS IN THE 30S WILL LIKELY SPREAD ACROSS MUCH OF CWA
NORTH OF I-80 THU NIGHT/EARLY FRIDAY AND INTO TYPICALLY COLD RURAL
LOCATIONS OF SCENT PENN...AND WILL HAVE TO KEEP AN EYE ON FOR
POTENTIAL FROST/FREEZE IMPACTS. THE HIGH TEMPS FRI WILL BE MAINLY
IN THE 60S AS NW FLOW CONTINUES.

RETURN FLOW BEGINS FRI NIGHT...TAKING A LITTLE OF THE BITE OUT OF
OVERNIGHT LOWS IN THE WEST WITH READINGS 5-8F WARMER. DRIER AIR
AND DECOUPLED LOW LEVELS WILL KEEP THE EAST COOLER...BUT STILL NOT
QUITE AS CHILLY AS THU NIGHT. THE RETURN FLOW WILL BEGIN A
WARMING TREND FOR THE WEEKEND. TEMPS SAT WILL BE 5-8F WARMER THAN
FRI...AND SUNDAY WILL BE EVEN A FEW DEGREES WARMER WITH HIGHS
APPROACHING 80F IN THE SE. LOWS WILL BE NOTICEABLY MILDER AS WELL
AS LOW LEVEL MOISTURE INCREASES IN STRENGTHENING SW FLOW.

HEADING INTO SUNDAY...MODELS STILL AGREE UPON A DEEPENING LOW
CENTERED WELL TO OUR NORTH AS A TROUGH AXIS ROTATES THROUGH THE
GREAT LAKES. THIS WILL BRING PLENTY OF CLOUDS AND A CHANCE FOR
SHOWERS...AND EVEN THOUGH GFS/ECMWF SETTLING IN ON
TIMING...STRENGTH OF SYSTEM STILL BEING DEBATED WITH GFS BRINGING
A MORE ROBUST SHOT OF PRECIP FOR LATER SUN/SUN NIGHT.

TROUGH SETTLES IN OVER PA FOR EARLY NEXT WEEK...WITH NW/N LOW
LEVEL FLOW BRINGING COOLER AND DRIER AIR INTO THE REGION. THERE
WILL LIKELY BE ENOUGH MID LEVEL INSTABILITY ON MONDAY TO LIMIT SUN
ACROSS NORTHERN AND CENTRAL MTNS...AND EVEN POTENTIALLY KICK OFF A
FEW LIGHT SHOWERS. TUE LOOKS CHILLIER AND DRY.

&&

.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRESSURE CENTERED OVER THE MIDWEST WILL DRIFT INTO THE REGION
TONIGHT. THE MCLEAR SKY AND NEARLY CALM WIND WILL PROMOTE LATE
NIGHT VALLEY FOG IN THE 07Z-13Z TIME FRAME. EXPECT AT LEAST A
BRIEF PERIOD OF IFR/LIFR VSBYS AT MOST CENTRAL PA AIRFIELDS.
LIKELY EXCEPTIONS WILL BE KJST AND KMDT...WHERE CLIMATOLOGY INDICATES
RADIATION FOG IS LESS LIKELY.

ANY FOG SHOULD BURN OFF BTWN 13Z-14Z. HIGH PRES AND ASSOC DRY AIR
MASS OVER THE REGION WILL TRANSLATE TO A NEAR CERTAINTY OF VFR
CONDS AND LIGHT WINDS FOR THE REST OF THE DAY.

OUTLOOK...
THU-FRI...PATCHY AM FOG POSSIBLE...MAINLY NORTH.
SAT-SUN...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD



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