Severe Thunderstorm Warning 93, NWS State College, PA

Area Forecast Discussion
National Weather Service State College PA
1005 PM EDT THU AUG 25 2016

.SYNOPSIS...
Thunderstorms should diminish as they move to the east overnight,
but will still make much of the area wet. A seasonably warm and
humid late- summer weather pattern will continue across Central
Pennsylvania into next week.

&&

.NEAR TERM /UNTIL 8 AM FRIDAY MORNING/...
Tiny, discrete supercells have now merged into one big bow echo
which should be accellerating through the CWA shortly. An MCV
seems to be forming in the central part of the bow. Weakening is
still forecast, but some CAPE above 1000 Joules is still available
to the east of the bow. EHI just above 1 in the swrn part of the
CWA. The shear along the southern fringe of the bow might still
make some rotation in any cells which can form away from the bow
and also at the tail end of the bow - much like just happened
north of PIT. Will follow the HRRR timing as it seems to have a
really good handle on current development/convection. It develops
the cold pool (if 72/70 can be considered cold) and accellerates
the bow thru the central mtns.

Prev...
Current radar mosaic over the NW seems rather benign at this time.
However, there have been a few cells with 50kft+ tops and
persistent rotation. So far, those nastier cells have stayed away
from the CWA. Have refined the timing just slightly with this
update. But, the main shot of precip is associated with a short
wave trough that is moving through wrn NY and wrn PA. Dewpoints
ahead of the line/s of showers are still in the l70s, and
inflow/source dewpoints are in the m70s from SWrn PA. Thus, these
showers (and the few tsra) should continue for a little while, but
near-term models still indicate significant weakening/scattering
as it moves through the c mtns.

Prev...
HRRR runs show convection entering nw cwa this evening. A few of
these storms will be quite strong with frequent lightning...gusty
winds and brief heavy downpours accompanying them as the move east
and southeast. Convection will weaken after sunset with loss of
heating...somewhere close to Centre County and points north
south...likely not making it much further east. After convection
diminishes look for another warm and humid night.

&&

.SHORT TERM /8 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Ridging will bring warm temperatures aloft to limit threat of
convection. Slight less surface moisture will make things feel more
comfortable though temperatures will once again top out well
above average.

Sfc high will build over the region Friday night, resulting in a
fair and mild night. Will have to watch for the possibility of
patchy valley fog over the northern mtns late.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Medium range guidance is in good agreement in keeping an anomalous ridge
aloft in place over the region into the early days of next week.
This will assure we remain warmer than normal with daytime highs
in the mid to upper 80s, low to mid 90s over southeastern areas,
at least into Tuesday.

By mid week week, weak troughing rippling through southern Canada
and the Great Lakes is made to erode the northern portion of the
northeastern ridge a bit, but only to the extent that upper
heights and temperatures fall back closer to normal values.

The NAEFS and GEFS end up carving out a weak mean trough by the
end of the week, but once again heights and temps are forecast to
be near seasonal norms so it should remain quite pleasant with
the biggest chance being a break in the humidity.

Chances for rain will be generally limited to scattered diurnal convection
each day, but with warm air aloft the chances should remain small
in the absence of well defined forcing. There is a period later
Sunday into Monday morning as we come under the northern edge of
the subtropical ridge and a weak cold front approaches, which
could be the first hints at the development of a more significant
MCS upstream. But with such a strong ridge aloft it's hard to be
confident at this range.

Main item of difference is the tropical system the ECMWF blows
up over the southeastern Gulf of Mexico early next week that the
GFS doesn't do much with at all. Both model suites agree with
the northern stream trough mentioned above to be enough to keep
any possible tropical developments well south of the local area.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
VFR conditions continue this evening across Central Pennsylvania.
Broken convection in far northwest Pennsylvania and Southwest New
York slowly making progress towards KBFD. Included mention of
VCTS in KBFD from 01z to 03z.

Short range models continue and try and carry convection into
Central Pa this evening, with activity reaching a KIPT-KUNV-KJST
line between 03z and 05z. At this point, have held off mention of
SHRA/TSRA in any of the other TAF locations...because of lower
confidence /30 POPs/. Will continue to monitor evolution of
activity for possible inclusion in TAFs.

For Friday, some morning restrictions should give way to VFR
conditions.

Outlook...

Fri...Morning restrictions in fog and lower ceilings, then VFR.
Sat...Patchy morning fog...otherwise VFR.
Sun...Mainly VFR...but isolated TSRA western 1/3 airspace in the
afternoon.
Mon-Tue...Isolated/Scattered thunderstorms possible.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

SYNOPSIS...Ross
NEAR TERM...Ross/Dangelo
SHORT TERM...Ross
LONG TERM...La Corte
AVIATION...Jung

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
329 PM EDT THU AUG 25 2016

PAZ004>006-010-011-017-261930-
WARREN-MCKEAN-POTTER-ELK-CAMERON-CLEARFIELD-
329 PM EDT THU AUG 25 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SCATTERED SEVERE THUNDERSTORMS WITH DAMAGING WINDS 60 MPH OR
GREATER ARE POSSIBLE THIS EVENING. AN ISOLATED TORNADO IS ALSO
POSSIBLE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

PAZ012-018-019-024>028-033-034-037-041-042-045-046-049>053-261930-
NORTHERN CLINTON-NORTHERN CENTRE-SOUTHERN CENTRE-CAMBRIA-BLAIR-
HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET-BEDFORD-TIOGA-NORTHERN LYCOMING-
SULLIVAN-SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR-
NORTHUMBERLAND-COLUMBIA-
329 PM EDT THU AUG 25 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

ISOLATED SEVERE THUNDERSTORMS WITH STRONG WINDS AND HAIL ARE
POSSIBLE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

PAZ035-036-056>059-063>066-261930-
FULTON-FRANKLIN-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND-ADAMS-
YORK-LANCASTER-
329 PM EDT THU AUG 25 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ACTIVATION IS NOT ANTICIPATED.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
821 PM EDT THU AUG 25 2016

PAZ010-260115-
ELK PA-
821 PM EDT THU AUG 25 2016

...SPECIAL WEATHER STATEMENT...

AT 820 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR
MARIENVILLE...MOVING EAST AT 25 MPH.

WINDS IN EXCESS OF 30 MPH ARE POSSIBLE.

LOCATIONS IMPACTED INCLUDE...
JOHNSONBURG...RIDGWAY...PORTLAND MILLS AND BRANDY CAMP.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 10 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL INFORMATION
AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4142 7909 4143 7906 4145 7906 4145 7898
      4144 7898 4144 7896 4154 7896 4151 7861
      4126 7872 4136 7895 4137 7897 4135 7902
      4136 7904 4135 7910
TIME...MOT...LOC 0020Z 286DEG 28KT 4146 7922

MARTIN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
833 PM EDT THU AUG 25 2016

PAZ004-005-260130-
MCKEAN PA-WARREN PA-
833 PM EDT THU AUG 25 2016

...SPECIAL WEATHER STATEMENT...

AT 833 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR
ENTERPRISE...MOVING EAST AT 30 MPH.

WINDS IN EXCESS OF 30 MPH ARE POSSIBLE.

LOCATIONS IMPACTED INCLUDE...
SHEFFIELD...CHAPMAN STATE PARK...LUDLOW...GRAND VALLEY AND TIDIOUTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL INFORMATION
AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4177 7961 4177 7889 4162 7892 4163 7961
TIME...MOT...LOC 0033Z 272DEG 33KT 4165 7952

MARTIN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
846 PM EDT THU AUG 25 2016

PAZ005-006-260145-
MCKEAN PA-POTTER PA-
846 PM EDT THU AUG 25 2016

...SPECIAL WEATHER STATEMENT...

AT 846 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER
BRADFORD...MOVING SOUTHEAST AT 30 MPH.

WINDS IN EXCESS OF 30 MPH ARE POSSIBLE.

LOCATIONS IMPACTED INCLUDE...
BRADFORD...SMETHPORT...SHINGLEHOUSE...CORYVILLE...REW...
PORT ALLEGANY...LEWIS RUN...ELDRED...CERES...
UNIVERSITY OF PITTSBURGH - BRADFORD...ROULETTE AND CYCLONE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL INFORMATION
AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4200 7802 4173 7819 4189 7878 4200 7870
TIME...MOT...LOC 0046Z 290DEG 32KT 4195 7861

MARTIN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
909 PM EDT THU AUG 25 2016

PAZ010-017-260145-
CLEARFIELD PA-ELK PA-
909 PM EDT THU AUG 25 2016

...SPECIAL WEATHER STATEMENT...

AT 909 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR
PORTLAND MILLS...MOVING EAST AT 25 MPH.

WINDS IN EXCESS OF 30 MPH ARE POSSIBLE.

LOCATIONS IMPACTED INCLUDE...
PORTLAND MILLS...FORCE...PENFIELD...BRANDY CAMP...
PARKER DAM STATE PARK...BROCKPORT...S.B. ELLIOT STATE PARK...
WEEDVILLE...KERSEY AND TREASURE LAKE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL INFORMATION
AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4145 7898 4144 7898 4144 7896 4145 7896
      4137 7843 4110 7852 4119 7877 4120 7877
      4120 7871 4123 7871 4123 7874 4127 7874
      4136 7895 4137 7897 4135 7902
TIME...MOT...LOC 0109Z 288DEG 24KT 4135 7893

MARTIN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
941 PM EDT THU AUG 25 2016

PAZ006-260215-
POTTER PA-
941 PM EDT THU AUG 25 2016

...SPECIAL WEATHER STATEMENT...

AT 940 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR
SHINGLEHOUSE...MOVING EAST AT 30 MPH.

WINDS IN EXCESS OF 30 MPH ARE POSSIBLE.

LOCATIONS IMPACTED INCLUDE...
SHINGLEHOUSE...GENESEE...OSWAYO...ULYSSES AND HARRISON VALLEY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL INFORMATION
AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4200 7764 4176 7767 4185 7821 4191 7821
      4200 7819
TIME...MOT...LOC 0140Z 280DEG 24KT 4196 7810

MARTIN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1003 PM EDT THU AUG 25 2016

PAZ010-011-017-260300-
CLEARFIELD PA-CAMERON PA-ELK PA-
1003 PM EDT THU AUG 25 2016

...SPECIAL WEATHER STATEMENT...

AT 1001 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER
FORCE...MOVING EAST AT 30 MPH. OTHER STRONG STORMS EXTEND SOUTHWEST
FROM THIS STORM.

WINDS IN EXCESS OF 30 MPH ARE POSSIBLE.

LOCATIONS IMPACTED INCLUDE...
CLEARFIELD...ST. MARYS...DUBOIS...SANDY...STEVENSON DAM...
MEDIX RUN...PENFIELD...ROCKTON...LECONTES MILLS...
PARKER DAM STATE PARK...JEFFRIES...HICKS RUN...WOODLAND...
BENEZETTE...BROCKPORT...S.B. ELLIOT STATE PARK...FORCE...
PLYMPTONVILLE...HYDE AND CURWENSVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE STORMS MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4142 7799 4139 7799 4086 7839 4091 7881
      4114 7880 4120 7877 4120 7871 4123 7871
      4123 7874 4127 7874 4147 7856
TIME...MOT...LOC 0201Z 289DEG 34KT 4126 7850

MARTIN