Alert archive / Pennsylvania / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 266
The Storm Prediction Center issued this severe thunderstorm watch at Jun 13, 2021, 3:26 PM EDT for 26 counties in Pennsylvania. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 13, 2021, 3:26 PM EDT (19:26 UTC)
- Expired
- Jun 13, 2021, 10:00 PM EDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 55 kt
All 26 counties
Blair County, PA, Bradford County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Elk County, PA, Huntingdon County, PA, Juniata County, PA, Lackawanna County, PA, Luzerne County, PA, Lycoming County, PA, McKean County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Potter County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Warren County, PA, Wyoming County, PA
The radar
The State College radar (KCCX), 90 km from the middle of the area, began a volume at 19:26 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 5%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 13, 3:45 PM EDT | Severe Thunderstorm Warning | CTP | Lycoming, Tioga | 45 min |
| Jun 13, 3:55 PM EDT | Severe Thunderstorm Warning | BGM | Bradford | 35 min |
| Jun 13, 4:22 PM EDT | Severe Thunderstorm Warning | CTP | Lycoming, Union | 83 min |
| Jun 13, 5:16 PM EDT | Severe Thunderstorm Warning | CTP | Clinton | 55 min |
| Jun 13, 6:51 PM EDT | Severe Thunderstorm Warning | CTP | Centre, Clinton | 54 min |
| Jun 13, 6:58 PM EDT | Severe Thunderstorm Warning | CTP | McKean, Warren | 32 min |
| Jun 13, 7:26 PM EDT | Severe Thunderstorm Warning | CTP | McKean | 49 min |
| Jun 13, 7:53 PM EDT | Severe Thunderstorm Warning | CTP | Blair, Centre, Huntingdon | 43 min |
| Jun 13, 8:10 PM EDT | Severe Thunderstorm Warning | CTP | McKean | 35 min |
| Jun 13, 8:41 PM EDT | Severe Thunderstorm Warning | CTP | McKean, Potter | 64 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 7.4 hours before the alert went out and 242 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
- 664 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 54 m²/s²
- 0-3 km storm-relative helicity
- 56 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
131 WWUS20 KWNS 131923 SEL6 SPC WW 131923 PAZ000-140200- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 266 NWS Storm Prediction Center Norman OK 325 PM EDT Sun Jun 13 2021 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern and central Pennsylvania * Effective this Sunday afternoon and evening from 325 PM until 1000 PM EDT. * Primary threats include... Scattered damaging wind gusts to 65 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Initial cellular activity across north-central Pennsylvania, along with additional development spreading east from western Pennsylvania will pose a risk for scattered damaging winds and isolated severe hail through most of the evening. The severe thunderstorm watch area is approximately along and 55 statute miles north and south of a line from 5 miles east northeast of Wilkesbarre PA to 5 miles southwest of Dubois PA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 264...WW 265... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 30025. ...Grams
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 13, 12:13 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Bedford, Butler, Cambria and 8 more | 2 hr |
| Jun 13, 12:50 PM EDT | Severe Thunderstorm Watch | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 9 more | 7 hr |
| Jun 13, 2:38 PM EDT | Mesoscale Discussion | SPC | Blair, Bradford, Cambria, Cameron, Centre, Clearfield and 20 more | 2 hr |
| Jun 13, 3:26 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 10 more | 94 min |
| Jun 13, 4:56 PM EDT | Mesoscale Discussion | SPC | Blair, Bradford, Cambria, Cameron, Centre, Clarion and 25 more | 94 min |
| Jun 13, 7:21 PM EDT | Mesoscale Discussion | SPC | Blair, Bradford, Cambria, Cameron, Carbon, Centre and 20 more | 84 min |
Nearby
Severe Thunderstorm Watches in Pennsylvania, 2021Every severe thunderstorm watch in 2021
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.