Alert archive / Delaware / Flash Flood Warnings in 2010
Flash Flood Warning 13, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 17, 2010, 2:36 PM EDT for Sussex County, Delaware. It was in force for 2 hr. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Aug 17, 2010, 2:36 PM EDT (18:36 UTC)
- Expired
- Aug 17, 2010, 4:40 PM EDT
- In force
- 2 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), 40 km from the middle of the area, began a volume at 18:36 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 17, 4:30 PM EDT | HEAVY RAIN 4 | Bethany Beach, DE | BOTH KDIX AND KDOX RADAR ESTIMATED STORM TOTALS AROUND 4 INCHES CENTERED IN AND NEAR BETHANY BEACH. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Wallops Is Stn, VA (KWAL), launched 12:00Z, 6.6 hours before the alert went out and 73 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
- 494 J/kg
- Mixed-layer CIN
- -70 J/kg
- Mixed-layer LCL
- 1086 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 36 m²/s²
- 0-3 km storm-relative helicity
- 36 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
The text
As transmitted, in the capitals the NWS used until 2016.
057
WGUS51 KPHI 171836
FFWPHI
DEC005-172130-
/O.NEW.KPHI.FF.W.0013.100817T1836Z-100817T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
236 PM EDT TUE AUG 17 2010
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* FLASH FLOOD WARNING FOR...
SOUTHEASTERN SUSSEX COUNTY IN SOUTHERN DELAWARE...
* UNTIL 530 PM EDT
* AT 230 PM EDT...HEAVY RAIN FOR PERSISTENT THUNDERSTORMS
CONTINUE TO FALL OVER SOUTHEASTERN SUSSEX COUNTY. DOPPLER
RADAR HAS ESTIMATED OVER TWO INCHES OF RAIN HAS FALLEN OVER THE
AREA AND ANOTHER ONE TO TWO INCHES OF RAIN ARE LIKELY BETWEEN
230 PM AND 330 PM. IN ADDITION WE ARE NEAR THE HIGH TIDE CYCLE.
* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO DAGSBORO
AND MILLVILLE
PRECAUTIONARY/PREPAREDNESS ACTIONS...
EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.
FLOODING IS IMMINENT. MOST FLOOD RELATED DEATHS OCCUR IN
AUTOMOBILES. DO NOT ATTEMPT TO CROSS WATER COVERED
BRIDGES...DIPS...OR LOW WATER CROSSINGS. NEVER TRY TO CROSS A
FLOWING STREAM...EVEN A SMALL ONE...ON FOOT. TO ESCAPE RISING WATER
MOVE UP TO HIGHER GROUND.
&&
LAT...LON 3845 7528 3859 7527 3860 7518 3861 7517
3860 7515 3860 7511 3859 7509 3860 7508
3862 7508 3862 7505 3847 7503 3844 7505
$$
TFG2 follow-up statements
365
WGUS71 KPHI 171934
FFSPHI
FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
334 PM EDT TUE AUG 17 2010
DEC005-172130-
/O.CON.KPHI.FF.W.0013.000000T0000Z-100817T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX DE-
334 PM EDT TUE AUG 17 2010
...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM EDT FOR
SOUTHEASTERN SUSSEX COUNTY...
AT 330 PM EDT...THUNDERSTORMS THAT PRODUCED THE FLASH FLOODING RAINS
HAVE MOVED OFFSHORE. THERE ARE NO ADDITIONAL THUNDERSTORMS UPWIND
AT THIS TIME AND FLOODING CONDITIONS SHOULD START IMPROVING IN THE
AREA. DOPPLER RADAR STORM TOTAL ESTIMATES REACHED NEARLY 4 INCHES
JUST TO THE NORTHWEST OF FENWICK ISLAND.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.
&&
LAT...LON 3845 7521 3854 7515 3857 7513 3857 7511
3858 7510 3858 7509 3859 7508 3859 7507
3860 7506 3860 7505 3847 7503 3844 7505
$$
TFG497
WGUS71 KPHI 172040
FFSPHI
FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
440 PM EDT TUE AUG 17 2010
DEC005-172049-
/O.CAN.KPHI.FF.W.0013.000000T0000Z-100817T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUSSEX DE-
440 PM EDT TUE AUG 17 2010
...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHEASTERN SUSSEX
COUNTY...
NO ONGOING FLOODING IS OCCURRING IN THE AREA AND THERE ARE CURRENTLY
NO THUNDERSTORMS UPSTREAM THAT ARE EXPECTED TO BRING HEAVY RAIN DURING
THE NEXT HOUR.
LAT...LON 3845 7521 3854 7515 3857 7513 3857 7511
3858 7510 3858 7509 3859 7508 3859 7507
3860 7506 3860 7505 3847 7503 3844 7505
$$
TFGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 16, 9:52 PM EDT | Special Weather Statement | PHI | New Castle | 113 min |
| Aug 17, 1:23 PM EDT | Special Weather Statement | PHI | Sussex | 82 min |
| Aug 17, 2:21 PM EDT | Areal Flood Advisory | PHI | Sussex | 114 min |
| Aug 17, 3:21 PM EDT | Special Weather Statement | PHI | Sussex | 54 min |
| Aug 17, 4:23 PM EDT | Special Weather Statement | PHI | Sussex | 112 min |
Nearby
Flash Flood Warnings in Delaware, 2010Every flash flood warning in 2010
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.