Alert archive / Pennsylvania / Mesoscale Discussions in 2012
Mesoscale Discussion 908
The Storm Prediction Center issued this mesoscale discussion at May 26, 2012, 1:17 PM EDT for 11 counties in New Jersey; 8 counties in New York; 16 counties in Pennsylvania. It was in force for 88 min.
The area
The outline as issued.
The facts
- Issued
- May 26, 2012, 1:17 PM EDT (17:17 UTC)
- Expired
- May 26, 2012, 2:45 PM EDT
- In force
- 88 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 35 counties
Bergen County, NJ, Essex County, NJ, Hudson County, NJ, Hunterdon County, NJ, Middlesex County, NJ, Morris County, NJ, Passaic County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Bronx County, NY, Kings County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Richmond County, NY, Rockland County, NY, Westchester County, NY, Berks County, PA, Bucks County, PA, Carbon County, PA, Columbia County, PA, Dauphin County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Monroe County, PA, Montgomery County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Pike County, PA, Schuylkill County, PA
The radar
The Philadelphia radar (KDIX), 116 km from the middle of the area, began a volume at 17:17 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 5.3 hours before the alert went out and 169 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
- 144 J/kg
- Mixed-layer CIN
- -138 J/kg
- Mixed-layer LCL
- 659 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- 42 m²/s²
- 0-3 km storm-relative helicity
- 105 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
348
ACUS11 KWNS 261717
SWOMCD
SPC MCD 261717
NYZ000-CTZ000-NJZ000-PAZ000-261845-
MESOSCALE DISCUSSION 0908
NWS STORM PREDICTION CENTER NORMAN OK
1217 PM CDT SAT MAY 26 2012
AREAS AFFECTED...PA...NY...NJ...CT
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 261717Z - 261845Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...ISOLATED TSTM DEVELOPMENT WAS UNDERWAY ALONG A COLD FRONT
SPREADING ACROSS NERN PA...SERN NY...AND SRN NEW ENGLAND. LATEST
OUTLOOK INCLUDES LOW PROBABILITY FORECAST FOR SOME HAIL/WIND EVENTS
AS THE FRONT MOVES ACROSS ERN PA/NRN NJ AND THE NYC AREA THROUGH THE
LATE AFTERNOON.
DISCUSSION...OVERALL STORM ORGANIZATION SHOULD BE LIMITED BY LACK OF
GREATER FLOW ACROSS THE REGION WITH UPSTREAM VWP DATA DEPICTING
DEEP-LAYER SHEAR AOB 10KT. HOWEVER...LIFT ALONG THE FRONT WAS MOVING
INTO A WARM AND UNCAPPED AIRMASS WHERE MLCAPE VALUES HAVE CLIMBED
INTO THE 1500-2000 J/KG RANGE. THESE FACTORS MAY OFFSET THE LACK OF
STRONGER SHEAR SO THAT ISOLATED CELLS COULD BRIEFLY ATTAIN SEVERE
POTENTIAL WITH DAMAGING WINDS AND HAIL NEAR 1 INCH. ATTM...SEVERE
STORM COVERAGE IS EXPECTED TO REMAIN TOO LIMITED FOR A WATCH.
..CARBIN.. 05/26/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OKX...ALY...PHI...BGM...CTP...
LAT...LON 41037331 40487415 39977593 40047651 40317689 40627706
40977688 41267598 41457484 41587389 41607360 41477301
41187294 41037331SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 26, 2:08 PM EDT | Mesoscale Discussion | SPC | 37 min | |
| May 26, 2:29 PM EDT | Severe Thunderstorm Watch | SPC | Greater Bridgeport Planning Region, Naugatuck Valley Planning Region | 6 hr |
| May 26, 6:04 PM EDT | Mesoscale Discussion | SPC | 56 min | |
| May 25, 9:18 PM EDT | Mesoscale Discussion | SPC | Cayuga, Franklin, Hamilton, Herkimer, Jefferson, Lewis and 5 more | 117 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2012Mesoscale Discussions in New Jersey, 2012Mesoscale Discussions in New York, 2012Every mesoscale discussion in 2012
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.