Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015
Severe Thunderstorm Warning 172, NWS Pittsburgh, PA
NWS Pittsburgh, PA issued this severe thunderstorm warning at Sep 4, 2015, 6:16 PM EDT for Clarion County, Pennsylvania. It was in force for 14 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 4, 2015, 6:16 PM EDT (22:16 UTC)
- Expired
- Sep 4, 2015, 6:30 PM EDT
- In force
- 14 min
- Issued by
- NWS Pittsburgh, PA
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
County Clarion County, PA
The radar
The Pittsburgh radar (KPBZ), 99 km from the middle of the area, began a volume at 22:19 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Pittsburgh, PA (KAGC), launched 12:00Z, 10.3 hours before the alert went out and 104 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 36 J/kg
- Mixed-layer CIN
- -156 J/kg
- Mixed-layer LCL
- 1202 m above ground
- 0-6 km bulk shear
- 3 kt
- 0-1 km storm-relative helicity
- -15 m²/s²
- 0-3 km storm-relative helicity
- 18 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Pittsburgh, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 4, 2:43 PM EDT, 3 hours 33 minutes earlier.
Area forecast discussion, Sep 4, 2:43 PM EDT, 3 hours 33 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 243 PM EDT FRI SEP 4 2015 .SYNOPSIS... WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... SHORTWAVE/WEAKNESS IN THE UPPER RIDGE WILL MAINTAIN THE CHANCE FOR SHOWERS AND THUNDERSTORMS THROUGH THE EVENING. IN ADDITION...RESIDUAL OUTFLOW BOUNDARIES FROM THIS MORNINGS COMPLEX WILL ALSO BE A CONTRIBUTING FACTOR...AND A FEW STORMS HAVE ALREADY DEVELOPED IN THE HIGHER TERRAIN. WITH NO SHEAR/UPPER LEVEL FLOW...MOST OF THESE STORMS WILL BE RATHER SHORT LIVED. THUS...SLIGHT TO LOW CHANCE POPS WERE MAINTAINED THROUGH THE PERIOD WITH MOST OF THE CONVECTION EXPECTED TO DISSIPATE WITH THE LOSS OF HEATING AT NIGHTFALL. WHILE TEMPERATURES WILL BE CONTINGENT ON CLOUD COVER AND COVERAGE OF STORMS THIS AFTERNOON...GENERALLY STAYED WITH A PERSISTENCE FORECAST WITH TEMPERATURES REMAINING 5 TO 10 DEGREES ABOVE SEASONAL AVERAGES. && .SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/... H500 RIDGE WILL REESTABLISH ITSELF OVER THE WEEKEND AND CONTINUE TO KEEP MOST WEATHER SYSTEMS AT BAY. WEAK FLOW OUT OF THE EAST AND SOUTHEAST...AROUND A SURFACE HIGH TO OUR EAST...WILL BRING A SLIGHTLY DRIER AND MORE STABLE AIRMASS ON SATURDAY. WITH PWATS FALLING AND H500 TEMPERATURES RISING...EXPECTING LESS DIURNAL CONVECTIVE COVERAGE. LIMITING POPS TO SLIGHT CHANCE...WITH AREAS NORTH AND EAST OF PIT STAYING DRY. RIDGE REACHES ITS BEST STRENGTH ON SUNDAY WITH H500 HEIGHTS AROUND 590DM. THINK CAPPING WILL BE STRONG ENOUGH TO SUPPRESS CONVECTION AND WILL KEEP THE DRY FORECAST GOING. IF POPS NEED TO BE ADDED EVENTUALLY...IT WOULD BE ALONG THE RIDGES. THE RIDGE STARTS TO WEAKEN ON MONDAY AS A LARGE UPPER LOW ACROSS CANADA MOVES EASTWARD...CAUSING HEIGHTS DOWNSTREAM TO BEGIN TO FALL. STILL...THE LACK OF MOISTURE...CONTINUED CAPPING...AND PERSISTENT SPRAWLING SURFACE HIGH WILL KEEP POPS BELOW 15. ANY SIGNIFICANT PRECIPITATION CHANCE WILL WAIT UNTIL MIDWEEK. TEMPERATURES WERE BASED ON A BLEND OF 12Z BIAS-CORRECTED MOSGUIDE AND PREVIOUS NUMBERS...WITH CONTINUED VALUES OF AROUND 10 DEGREES ABOVE NORMAL. CL && .LONG TERM /TUESDAY THROUGH FRIDAY/... THE STRONG MID/UPPER RIDGE IS PROGGED TO REMAIN THROUGH EARLY NEXT WEEK...WITH CONTINUED WARM AND MUGGY CONDITIONS. RELIEF FROM THE QUITE WARM CONDITIONS MAY COME WITH COLD FRONT LATER WEDNESDAY INTO THURSDAY...AS WELL AS AN INCREASING CHANCE FOR THUNDERSTORMS. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... EXPECT PREVAILING VFR CONDITIONS FOR MUCH OF THE AFTERNOON AND EVENING WITH A SMALL CHANCE OF RESTRICTIONS IN ANY SHOWER OR THUNDERSTORM THAT PASSES DIRECTLY OVER A TAF SITE. WITH LIMITED CONFIDENCE IN ANY ONE SPECIFIC PORT BEING IMPACTED...OPTED TO LEAVE TS MENTION OUT FOR NOW. EXPECT ANOTHER ROUND OF FOG OVERNIGHT WITH PLENTY OF LOW LEVEL MOISTURE AND LITTLE MIXING. OUTLOOK...FRIDAY THROUGH TUESDAY... GENERAL VFR WITH BRIEF RESTRICTIONS IN EARLY MORNING FOG IS ANTICIPATED EACH DAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. &&
Hazardous weather outlook, Sep 4, 4:23 AM EDT, 13 hours 53 minutes before
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE PITTSBURGH PA 423 AM EDT FRI SEP 4 2015 MDZ001-OHZ039>041-048>050-057>059-068-069-PAZ007>009-013>016-020>023- 029-031-073>076-WVZ001>004-012-021>023-041-050830- GARRETT-TUSCARAWAS-CARROLL-COLUMBIANA-COSHOCTON-HARRISON- JEFFERSON OH-MUSKINGUM-GUERNSEY-BELMONT-NOBLE-MONROE-MERCER-VENANGO- FOREST-LAWRENCE-BUTLER-CLARION-JEFFERSON PA-BEAVER-ALLEGHENY- ARMSTRONG-INDIANA-WASHINGTON-GREENE-WESTMORELAND-WESTMORELAND RIDGES- FAYETTE-FAYETTE RIDGES-HANCOCK-BROOKE-OHIO-MARSHALL-WETZEL-MARION- MONONGALIA-PRESTON-TUCKER- 423 AM EDT FRI SEP 4 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN MARYLAND...EAST CENTRAL OHIO...NORTHWEST PENNSYLVANIA...SOUTHWEST PENNSYLVANIA...WEST CENTRAL PENNSYLVANIA...NORTHERN WEST VIRGINIA AND NORTHERN PANHANDLE OF WEST VIRGINIA. .DAY ONE...TODAY AND TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
In the hours before
Special weather statement, Sep 4, 5:21 PM EDT, 55 minutes before
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</html>Special weather statement, Sep 4, 5:51 PM EDT, 25 minutes before
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</html>Local storm report, Sep 4, 6:02 PM EDT, 14 minutes before
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</html>Special weather statement, Sep 4, 6:09 PM EDT, 7 minutes before
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</html>The office that day
Everything else NWS Pittsburgh, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 3, 8:21 PM EDT | Special Weather Statement | PBZ | Venango | 24 min |
| Sep 4, 3:43 PM EDT | Special Weather Statement | PBZ | Indiana | 32 min |
| Sep 4, 5:21 PM EDT | Special Weather Statement | PBZ | Westmoreland | 24 min |
| Sep 4, 5:26 PM EDT | Special Weather Statement | PBZ | Fayette | 19 min |
| Sep 4, 5:31 PM EDT | Special Weather Statement | PBZ | Armstrong | 14 min |
| Sep 4, 5:51 PM EDT | Special Weather Statement | PBZ | Clarion | 24 min |
| Sep 4, 6:09 PM EDT | Special Weather Statement | PBZ | Clarion | 36 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2015Every severe thunderstorm warning in 2015
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.