Alert archive / Pennsylvania / Areal Flood Warnings in 2019

Areal Flood Warning 21, NWS Philadelphia/Mount Holly

June 10, 2019Chester County, Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood warning at Jun 10, 2019, 11:25 PM EDT for Chester County, Delaware County, Pennsylvania. It was in force for 112 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 10, 2019, 11:25 PM EDT (03:25 UTC)
Expired
Jun 11, 2019, 1:17 AM EDT
In force
112 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Chester County, PA, Delaware County, PA

The radar

The Philadelphia radar (KDIX), 90 km from the middle of the area, began a volume at 03:27 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 00:00Z, 3.4 hours before the alert went out and 203 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.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2019-06-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2019-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
671 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
72 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

352 
WGUS41 KPHI 110325
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
1125 PM EDT Mon Jun 10 2019

PAC029-045-110730-
/O.NEW.KPHI.FA.W.0021.190611T0325Z-190611T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-Delaware PA-
1125 PM EDT Mon Jun 10 2019

The National Weather Service in Mount Holly NJ has issued a

* Flood Warning for...
  Eastern Chester County in southeastern Pennsylvania...
  Central Delaware County in southeastern Pennsylvania...

* Until 330 AM EDT.

* At 1122 PM EDT, reporting gauges have indicated minor flooding is 
  occurring at Crum Creek near Newtown Square. Up to two inches of 
  rain have already fallen over the area with additional rainfall 
  possible over the next few hours.

* Flooding will remain over mainly rural areas of eastern Chester and
  central Delaware Counties.


LAT...LON 4003 7547 3997 7539 3996 7545 4001 7554

$$

NC
1 follow-up statement
344 
WGUS81 KPHI 110517
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
117 AM EDT Tue Jun 11 2019

PAC029-045-110524-
/O.CAN.KPHI.FA.W.0021.000000T0000Z-190611T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-Delaware PA-
117 AM EDT Tue Jun 11 2019

...THE FLOOD WARNING HAS BEEN CANCELLED FOR EASTERN CHESTER AND
CENTRAL DELAWARE COUNTIES...

The level of Crum's Creek has dropped down below flood stage over 
the past hour and thus the flood warning is cancelled.  

LAT...LON 4003 7547 3997 7539 3996 7545 4001 7554

$$

NC

Nearby

Areal Flood Warnings in Pennsylvania, 2019Every areal flood warning in 2019

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.