Alert archive / Pennsylvania / Flash Flood Watches in 2021
Flash Flood Watch 6, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood watch at Aug 17, 2021, 3:09 PM EDT for 5 counties in Pennsylvania. It took effect at Aug 18, 2021, 2:00 PM EDT. It was in force for 13 hr.
The area
The counties it named.
The facts
- Issued
- Aug 17, 2021, 3:09 PM EDT (19:09 UTC)
- In effect from
- Aug 18, 2021, 2:00 PM EDT
- Expired
- Aug 19, 2021, 2:50 AM EDT
- In force
- 13 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Flood severity
- None
Counties Berks County, PA, Carbon County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA
The radar
The Philadelphia radar (KDIX), 133 km from the middle of the area, began a volume at 19:10 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
Brookhaven, NY (KOKX), launched 12:00Z, 7.2 hours before the alert went out and 228 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
- 1036 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- -7 m²/s²
- 0-3 km storm-relative helicity
- 11 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
468 WGUS61 KPHI 171909 FFAPHI URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Mount Holly NJ 309 PM EDT Tue Aug 17 2021 PAZ054-055-060>062-180715- /O.NEW.KPHI.FF.A.0006.210818T1800Z-210819T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Carbon-Monroe-Berks-Lehigh-Northampton- Including the cities of Jim Thorpe, Allentown, Bethlehem, Stroudsburg, Reading, and Easton 309 PM EDT Tue Aug 17 2021 ...FLASH FLOOD WATCH IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING... The National Weather Service in Mount Holly has issued a * Flash Flood Watch for portions of east central Pennsylvania...and northeast Pennsylvania...including the following areas...in east central Pennsylvania...Berks, Lehigh, and Northampton. In northeast Pennsylvania...Carbon and Monroe. * From Wednesday afternoon through Thursday morning. * Heavy rainfall associated with the remnants of Tropical Storm Fred will move into the area Wednesday afternoon and evening. Forecast rainfall amounts of 1 to 3 inches are expected with locally higher amounts possible. $$ Staarmann
3 follow-up statements
599 WGUS61 KPHI 180645 FFAPHI Flood Watch National Weather Service Mount Holly NJ 245 AM EDT Wed Aug 18 2021 PAZ054-055-060>062-182015- /O.CON.KPHI.FF.A.0006.210818T1800Z-210819T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Carbon-Monroe-Berks-Lehigh-Northampton- Including the cities of Jim Thorpe, Allentown, Bethlehem, Stroudsburg, Reading, and Easton 245 AM EDT Wed Aug 18 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH THURSDAY MORNING... The Flash Flood Watch continues for * Portions of east central Pennsylvania...and northeast Pennsylvania...including the following areas...in east central Pennsylvania...Berks, Lehigh, and Northampton. In northeast Pennsylvania...Carbon and Monroe. * From 2 PM EDT this afternoon through Thursday morning. * Heavy rainfall associated with the remnants of Tropical Storm Fred will move into the area this afternoon and evening. Rainfall amounts of 1 to 3 inches are expected with locally higher amounts possible. This may lead to areas of flash flooding. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ JEO
457 WGUS61 KPHI 181957 FFAPHI Flood Watch National Weather Service Mount Holly NJ 357 PM EDT Wed Aug 18 2021 PAZ054-055-060>062-190800- /O.CON.KPHI.FF.A.0006.000000T0000Z-210819T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Carbon-Monroe-Berks-Lehigh-Northampton- Including the cities of Jim Thorpe, Allentown, Bethlehem, Stroudsburg, Reading, and Easton 357 PM EDT Wed Aug 18 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY MORNING... The Flash Flood Watch continues for * Portions of east central Pennsylvania...and northeast Pennsylvania...including the following areas...in east central Pennsylvania...Berks, Lehigh, and Northampton. In northeast Pennsylvania...Carbon and Monroe. * Through Thursday morning. * Heavy rainfall associated with the remnants of Tropical Storm Fred will move into the area this afternoon and evening. Rainfall amounts of 1 to 3 inches are expected with locally higher amounts possible. This may lead to areas of flash flooding. $$ Davis
001 WGUS61 KPHI 190650 FFAPHI Flood Watch National Weather Service Mount Holly NJ 250 AM EDT Thu Aug 19 2021 PAZ054-055-060>062-190800- /O.CAN.KPHI.FF.A.0006.000000T0000Z-210819T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Carbon-Monroe-Berks-Lehigh-Northampton- Including the cities of Jim Thorpe, Allentown, Bethlehem, Stroudsburg, Reading, and Easton 250 AM EDT Thu Aug 19 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for portions of east central Pennsylvania... and northeast Pennsylvania...including the following areas...in east central Pennsylvania...Berks, Lehigh, and Northampton. In northeast Pennsylvania...Carbon and Monroe has been cancelled. The Flood Watch is cancelled. Flooding is no longer expected to pose a threat. Please continue to heed remaining road closures. $$ SFJ
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.