Alert archive / Delaware / Flash Flood Warnings in 2013

Flash Flood Warning 49, NWS Philadelphia/Mount Holly

August 1, 2013Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 1, 2013, 5:58 PM EDT for Sussex County, Delaware. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 1, 2013, 5:58 PM EDT (21:58 UTC)
Expired
Aug 1, 2013, 10:00 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 39 km from the middle of the area, began a volume at 22:00 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

Wallops Is Stn, VA (KWAL), launched 12:00Z, 10.0 hours before the alert went out and 70 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, Wallops Is Stn, VA at 12:00Z on 2013-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 23 joules per kilogram.LCLLFCEL10008507005003002001001 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, Wallops Is Stn, VA at 12:00Z on 2013-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 square meters per square second.19395878Sfc1 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
23 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
972 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
167 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

354 
WGUS51 KPHI 012158
FFWPHI
DEC005-020200-
/O.NEW.KPHI.FF.W.0049.130801T2158Z-130802T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
558 PM EDT THU AUG 1 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN SUSSEX COUNTY...

* UNTIL 1000 PM EDT...

* AT 551 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM OVER SOUTHEASTERN SUSSEX
  COUNTY.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO RURAL AREAS
  OF SOUTHEASTERN SUSSEX COUNTY.

OBSERVED RAINFALL OF OVER THREE AND A HALF INCHES HAS BEEN REPORTED 
FROM DEOS OBSERVATION SITES IN BETHANY BEACH AND SELBYVILLE

ADDITIONAL RAINFALL AMOUNTS OF ONE TO THREE INCHES ARE POSSIBLE IN 
THE WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. NEVER ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR IN AN
AUTOMOBILE. TURN AROUND DON'T DROWN!

&&

LAT...LON 3855 7537 3862 7515 3864 7506 3859 7505
      3845 7504 3845 7505 3845 7536

$$

FORECASTER:
SZATKOWSKI
1 follow-up statement
141 
WGUS71 KPHI 020000
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
800 PM EDT THU AUG 1 2013

DEC005-020008-
/O.CAN.KPHI.FF.W.0049.000000T0000Z-130802T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX DE-
800 PM EDT THU AUG 1 2013

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHEASTERN SUSSEX
COUNTY...

THE WATERS FROM THE EARLIER HEAVY RAINS ARE RECEDING AND FLOOD WATERS
NO LONGER POSE A THREAT TO LIFE OR PROPERTY. THEREFORE...THE FLASH
FLOOD WARNING HAS BEEN CANCELLED.

WATER IS RECEDING...BUT JUST SOME MINOR FLOODING PROBLEMS MAY
CONTINUE FOR AN HOUR OR TWO.

LAT...LON 3855 7537 3862 7515 3864 7506 3859 7505
      3845 7504 3845 7505 3845 7536

$$

FORECASTER:
SZATKOWSKI

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 1, 3:42 AM EDTFlash Flood WatchPHINew Castle14 hr
Aug 1, 10:50 AM EDTAreal Flood AdvisoryPHINew Castle3 hr
Aug 1, 11:57 AM EDTRiver Flood WarningPHINew Castle3 hr
Aug 1, 12:17 PM EDTSpecial Weather StatementPHIKent43 min
Aug 1, 12:48 PM EDTAreal Flood AdvisoryPHIKent, Sussex3 hr
Aug 1, 12:50 PM EDTSevere Thunderstorm WarningPHISussex40 min
Aug 1, 1:12 PM EDTSevere Thunderstorm WarningPHISussex48 min
Aug 1, 2:35 PM EDTAreal Flood AdvisoryPHISussex3 hr
Aug 1, 2:57 PM EDTFlash Flood WarningPHISussex3 hr

Nearby

Flash Flood Warnings in Delaware, 2013Every flash flood warning in 2013

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.