Alert archive / Pennsylvania / Mesoscale Discussions in 2003
Mesoscale Discussion 2313
The Storm Prediction Center issued this mesoscale discussion at Aug 29, 2003, 4:51 PM EDT for 5 counties in Ohio; 18 counties in Pennsylvania. It was in force for 84 min.
The area
The outline as issued.
The facts
- Issued
- Aug 29, 2003, 4:51 PM EDT (20:51 UTC)
- Expired
- Aug 29, 2003, 6:15 PM EDT
- In force
- 84 min
- Issued by
- the Storm Prediction Center
All 23 counties
Carroll County, OH, Columbiana County, OH, Mahoning County, OH, Stark County, OH, Tuscarawas County, OH, Armstrong County, PA, Beaver County, PA, Butler County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Elk County, PA, Forest County, PA, Jefferson County, PA, Lawrence County, PA, Lycoming County, PA, McKean County, PA, Mercer County, PA, Potter County, PA, Tioga County, PA, Venango County, PA
The radar
The Pittsburgh radar (KPBZ), 72 km from the middle of the area, began a volume at 20:51 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 (KPIT), launched 12:00Z, 8.9 hours before the alert went out and 84 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
- 1227 J/kg
- Mixed-layer CIN
- -26 J/kg
- Mixed-layer LCL
- 756 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 52 m²/s²
- 0-3 km storm-relative helicity
- 53 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.4
The text
As transmitted, in the capitals the NWS used until 2016.
000 ACUS11 KWNS 292052 SWOMCD SPC MCD 292051 PAZ000-NYZ000-OHZ000-WVZ000-292215- MESOSCALE DISCUSSION 2313 NWS STORM PREDICTION CENTER NORMAN OK 0351 PM CDT FRI AUG 29 2003 AREAS AFFECTED...PORTIONS ERN OH...NWRN PA CONCERNING...SEVERE THUNDERSTORM WATCH 909... VALID 292051Z - 292215Z LINE OF STRONG-SEVERE TSTMS WILL MOVE EWD ACROSS NW PA...WHILE MORE WIDELY SCATTERED TSTMS MOVE EWD ACROSS OH PORTION WW...BEFORE SCHEDULED 23Z WW EXPIRATION. MAIN THREAT REMAINS DAMAGING WIND...WITH ISOLATED LARGE HAIL PSBL. VWP DATA AND MODIFIED RUC2 SOUNDINGS INDICATE SRN PERIPHERY OF BELT OF 30-40 KT MIDLEVEL FLOW WILL REMAIN OVER THIS REGION. THIS WILL CONTRIBUTE SUFFICIENT VERTICAL SHEAR TO SUPPORT DAMAGING CONVECTIVE GUSTS...IN NEARLY UNIDIRECTIONAL AMBIENT WIND PROFILE...PARTICULARLY FOR BOW/LEWP FORMATIONS THAT BECOME ORIENTED SIGNIFICANTLY PERPENDICULAR TO MEAN FLOW. AT SFC...SECONDARY ISALLOBARIC MIN....ANALYZED N-CENTRAL/NERN PA...MAY AID IN VERTICAL SHEAR OVER THAT REGION THROUGH ASSOCIATED MESO-BETA SCALE FLOW BACKING. UPPER 60S TO 70S F SFC DEW POINTS SHOULD CONTINUE TO CONTRIBUTE TO 1500-2000 J/KG MLCAPE. ..EDWARDS.. 08/29/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BGM...BUF...CTP...PBZ...CLE... 40338192 40758191 40988119 41368024 41567961 41907918 42187692 41037692 ACUS11 KWNS 292052 SWOMCD SPC MCD 292051 PAZ000-NYZ000-OHZ000-WVZ000-292215- MESOSCALE DISCUSSION 2313 NWS STORM PREDICTION CENTER NORMAN OK 0351 PM CDT FRI AUG 29 2003 AREAS AFFECTED...PORTIONS ERN OH...NWRN PA CONCERNING...SEVERE THUNDERSTORM WATCH 909... VALID 292051Z - 292215Z LINE OF STRONG-SEVERE TSTMS WILL MOVE EWD ACROSS NW PA...WHILE MORE WIDELY SCATTERED TSTMS MOVE EWD ACROSS OH PORTION WW...BEFORE SCHEDULED 23Z WW EXPIRATION. MAIN THREAT REMAINS DAMAGING WIND...WITH ISOLATED LARGE HAIL PSBL. VWP DATA AND MODIFIED RUC2 SOUNDINGS INDICATE SRN PERIPHERY OF BELT OF 30-40 KT MIDLEVEL FLOW WILL REMAIN OVER THIS REGION. THIS WILL CONTRIBUTE SUFFICIENT VERTICAL SHEAR TO SUPPORT DAMAGING CONVECTIVE GUSTS...IN NEARLY UNIDIRECTIONAL AMBIENT WIND PROFILE...PARTICULARLY FOR BOW/LEWP FORMATIONS THAT BECOME ORIENTED SIGNIFICANTLY PERPENDICULAR TO MEAN FLOW. AT SFC...SECONDARY ISALLOBARIC MIN....ANALYZED N-CENTRAL/NERN PA...MAY AID IN VERTICAL SHEAR OVER THAT REGION THROUGH ASSOCIATED MESO-BETA SCALE FLOW BACKING. UPPER 60S TO 70S F SFC DEW POINTS SHOULD CONTINUE TO CONTRIBUTE TO 1500-2000 J/KG MLCAPE. ..EDWARDS.. 08/29/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BGM...BUF...CTP...PBZ...CLE... 40338192 40758191 40988119 41368024 41567961 41907918 42187692 41037692
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 29, 4:31 AM EDT | Mesoscale Discussion | SPC | Williams | 119 min |
| Aug 29, 1:32 PM EDT | Mesoscale Discussion | SPC | Ashland, Ashtabula, Carroll, Champaign, Clark, Columbiana and 33 more | 2 hr |
| Aug 29, 2:05 PM EDT | Severe Thunderstorm Watch | SPC | Carroll, Columbiana, Geauga, Mahoning, Medina, Portage and 5 more | 5 hr |
| Aug 29, 2:59 PM EDT | Mesoscale Discussion | SPC | Adams, Bedford, Berks, Bucks, Carbon, Chester and 24 more | 3 hr |
| Aug 29, 3:50 PM EDT | Severe Thunderstorm Watch | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Lebanon and 3 more | 5 hr |
Nearby
Mesoscale Discussions in Pennsylvania, 2003Mesoscale Discussions in Ohio, 2003Every mesoscale discussion in 2003
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.