Alert archive / Pennsylvania / Mesoscale Discussions in 2023
Mesoscale Discussion 430
The Storm Prediction Center issued this mesoscale discussion at Apr 1, 2023, 2:02 PM EDT for 18 counties in New York; 36 counties in Pennsylvania. It was in force for 118 min.
The area
The outline as issued.
The facts
- Issued
- Apr 1, 2023, 2:02 PM EDT (18:02 UTC)
- Expired
- Apr 1, 2023, 4:00 PM EDT
- In force
- 118 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch likely
- Chance of a watch
- 95%
All 54 counties
Allegany County, NY, Broome County, NY, Cattaraugus County, NY, Cayuga County, NY, Chautauqua County, NY, Chemung County, NY, Cortland County, NY, Erie County, NY, Genesee County, NY, Livingston County, NY, Ontario County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Wyoming County, NY, Yates County, NY, Armstrong County, PA, Bedford County, PA, Blair County, PA, Bradford County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Elk County, PA, Fayette County, PA, Forest County, PA, Fulton County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Juniata County, PA, Lycoming County, PA, McKean County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Perry County, PA, Potter County, PA, Snyder County, PA, Somerset County, PA, Sullivan County, PA, Tioga County, PA, Union County, PA, Warren County, PA, Westmoreland County, PA, Wyoming County, PA
The radar
The State College radar (KCCX), 34 km from the middle of the area, began a volume at 18:03 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
Pittsburgh, PA (KPIT), launched 12:00Z, 6.0 hours before the alert went out and 181 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1502 m above ground
- 0-6 km bulk shear
- 104 kt
- 0-1 km storm-relative helicity
- -163 m²/s²
- 0-3 km storm-relative helicity
- -117 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
708
ACUS11 KWNS 011803
SWOMCD
SPC MCD 011802
NYZ000-PAZ000-012000-
Mesoscale Discussion 0430
NWS Storm Prediction Center Norman OK
0102 PM CDT Sat Apr 01 2023
Areas affected...parts of central Pennsylvania into New York
Concerning...Severe potential...Watch likely
Valid 011802Z - 012000Z
Probability of Watch Issuance...95 percent
SUMMARY...An arcing line of convection along the cold front is
likely to produce severe gusts over the next several hours. An
additional watch may be required soon.
DISCUSSION...A line of convection along the cold front will continue
to push east quickly across western NY and into central PA. This
line continues to produce wind gusts over 50 kt with damage reports.
Instability is currently maximized over western PA with MUCAPE
around 500 J/kg, and surface observations east of the existing watch
show quite a bit of mixing with dewpoints averaging the mid 30s F.
However, continued cooling aloft and mixing down of winds,
especially beneath the stronger reflectivities, will continue to
pose a severe wind threat downstream across NY and PA. The line will
gradually encounter better dewpoints as it crosses into eastern PA
and NY, and this may result in an even greater risk of severe
storms, to be addressed later today.
..Jewell/Guyer.. 04/01/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BGM...BUF...CTP...PBZ...CLE...
LAT...LON 39968002 40517970 41187950 42027963 42847931 43247662
42867598 42357576 41677583 40527654 39977755 39777881
39767968 39968002SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 1, 11:15 AM EDT | Mesoscale Discussion | SPC | Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 1 more | 3 hr |
| Apr 1, 11:59 AM EDT | Severe Thunderstorm Watch | SPC | Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 6 more | 5 hr |
| Apr 1, 2:27 PM EDT | Severe Thunderstorm Watch | SPC | Broome, Cayuga, Chemung, Chenango, Cortland, Delaware and 11 more | 5 hr |
| Apr 1, 4:37 PM EDT | Mesoscale Discussion | SPC | Bronx, Kings, New York, Orange, Queens, Richmond and 2 more | 113 min |
| Apr 1, 5:16 PM EDT | Severe Thunderstorm Watch | SPC | Albany, Bronx, Columbia, Dutchess, Fulton, Greene and 17 more | 3 hr |
| Apr 1, 5:30 PM EDT | Tornado Watch | SPC | Bucks, Chester, Delaware, Montgomery, Philadelphia | 5 hr |
| Apr 1, 6:55 PM EDT | Mesoscale Discussion | SPC | Delaware, Philadelphia | 95 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2023Mesoscale Discussions in New York, 2023Every mesoscale discussion in 2023
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.