Alert archive / Delaware / Flash Flood Warnings in 2015

Flash Flood Warning 44, NWS Philadelphia/Mount Holly

August 5, 2015Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 5, 2015, 12:39 AM 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 5, 2015, 12:39 AM EDT (04:39 UTC)
Expired: Aug 5, 2015, 4:45 AM 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), 32 km from the middle of the area, began a volume at 04:38 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 00:00Z, 4.7 hours before the alert went out and 67 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 961 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 1098 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 75 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

806 
WGUS51 KPHI 050439
FFWPHI
DEC005-050845-
/O.NEW.KPHI.FF.W.0044.150805T0439Z-150805T0845Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1239 AM EDT WED AUG 5 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTH CENTRAL SUSSEX COUNTY IN SOUTHERN DELAWARE...

* UNTIL 445 AM EDT
    
* AT 1238 AM EDT...DOPPLER RADAR INDICATED A THUNDERSTORM PRODUCING 
  HEAVY RAIN ACROSS THE WARNED AREA. UP TO TWO TO THREE INCHES OF 
  RAIN HAVE ALREADY FALLEN. FLASH FLOODING IS EXPECTED TO BEGIN 
  SHORTLY.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  MILLSBORO.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO HIGHER GROUND NOW. ACT QUICKLY TO PROTECT YOUR LIFE.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING.

&&

LAT...LON 3848 7549 3860 7548 3863 7529 3849 7526

$$

ROBERTSON

1 follow-up statement

436 
WGUS71 KPHI 050637
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
237 AM EDT WED AUG 5 2015

DEC005-050646-
/O.CAN.KPHI.FF.W.0044.000000T0000Z-150805T0845Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX DE-
237 AM EDT WED AUG 5 2015

...THE FLASH FLOOD WARNING FOR SOUTH CENTRAL SUSSEX COUNTY IS
CANCELLED...

THE HEAVY RAIN HAS ENDED...AND FLOODING IS NO LONGER EXPECTED TO POSE
A THREAT.

LAT...LON 3848 7549 3860 7548 3863 7529 3849 7526

$$

ROBERTSON

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 4, 9:01 PM EDT	Special Weather Statement	PHI	New Castle	59 min
Aug 4, 10:24 PM EDT	Special Weather Statement	PHI	Sussex	51 min
Aug 4, 11:06 PM EDT	Special Weather Statement	PHI	Sussex	24 min
Aug 4, 11:18 PM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Aug 4, 11:28 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	32 min
Aug 4, 11:35 PM EDT	Flash Flood Warning	PHI	Sussex	4 hr
Aug 4, 11:43 PM EDT	Special Weather Statement	PHI	Sussex	47 min
Aug 5, 12:04 AM EDT	Special Weather Statement	PHI	Sussex	41 min
Aug 5, 12:52 AM EDT	Special Weather Statement	PHI	Sussex	23 min

Nearby

Flash Flood Warnings in Delaware, 2015 Every flash flood warning in 2015

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.