Alert archive / Pennsylvania / Flash Flood Watches in 2021
Flash Flood Watch 9, NWS State College, PA
NWS State College, PA issued this flash flood watch at Sep 8, 2021, 6:21 PM EDT for Adams County, Lancaster County, York County, Pennsylvania. It took effect at Sep 8, 2021, 8:00 PM EDT. It was in force for 5 hr.
The area
The counties it named.
The facts
- Issued
- Sep 8, 2021, 6:21 PM EDT (22:21 UTC)
- In effect from
- Sep 8, 2021, 8:00 PM EDT
- Expired
- Sep 9, 2021, 1:00 AM EDT
- In force
- 5 hr
- Issued by
- NWS State College, PA
- Flood severity
- None
Counties Adams County, PA, Lancaster County, PA, York County, PA
The radar
The Sterling radar (KLWX), 126 km from the middle of the area, began a volume at 22:24 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 10.4 hours before the alert went out and 125 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
- 1137 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 127 m²/s²
- 0-3 km storm-relative helicity
- 137 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
533 WGUS61 KCTP 082221 FFACTP URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service State College PA 621 PM EDT Wed Sep 8 2021 PAZ064>066-090500- /O.NEW.KCTP.FF.A.0009.210909T0000Z-210909T0500Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Adams-York-Lancaster- Including the cities of Lancaster, Gettysburg, and York 621 PM EDT Wed Sep 8 2021 ...FLASH FLOOD WATCH IN EFFECT UNTIL 1 AM EDT THURSDAY... The National Weather Service in State College has issued a * Flash Flood Watch for a portion of central Pennsylvania, including the following areas, Adams, Lancaster and York. * Until 1 AM EDT Thursday. * A cold front moving into the area will likely produce heavy showers and thunderstorms this evening. Localized rain totals of over 2 inches are possible, which would cause flooding due to the already wet ground. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ KF
The office that day
Everything else NWS State College, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 8, 3:07 PM EDT | Special Weather Statement | CTP | Lycoming | 23 min |
| Sep 8, 3:12 PM EDT | Special Weather Statement | CTP | Centre | 33 min |
| Sep 8, 3:27 PM EDT | Severe Thunderstorm Warning | CTP | Lycoming, Sullivan | 33 min |
| Sep 8, 3:29 PM EDT | Special Weather Statement | CTP | Blair | 31 min |
| Sep 8, 3:59 PM EDT | Special Weather Statement | CTP | Huntingdon | 31 min |
| Sep 8, 4:29 PM EDT | Special Weather Statement | CTP | Mifflin | 46 min |
| Sep 8, 4:36 PM EDT | Severe Thunderstorm Warning | CTP | Juniata, Mifflin, Snyder | 39 min |
| Sep 8, 5:11 PM EDT | Severe Thunderstorm Warning | CTP | Juniata, Northumberland, Snyder | 49 min |
| Sep 8, 5:57 PM EDT | Severe Thunderstorm Warning | CTP | Columbia, Northumberland, Schuylkill | 37 min |
| Sep 8, 6:36 PM EDT | Special Weather Statement | CTP | Columbia | 39 min |
| Sep 8, 7:18 PM EDT | Special Weather Statement | CTP | Carbon | 27 min |
| Sep 8, 7:43 PM EDT | Special Weather Statement | CTP | Schuylkill | 17 min |
Nearby
Flash Flood Watches in Pennsylvania, 2021Every flash flood 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.