Alert archive / Maryland / Areal Flood Advisories in 2016

Areal Flood Advisory 21, NWS Philadelphia/Mount Holly

May 2, 2016Queen Anne's County, Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this areal flood advisory at May 2, 2016, 9:47 PM EDT for Queen Anne's County, Talbot County, Maryland. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: May 2, 2016, 9:47 PM EDT (01:47 UTC)
Expired: May 3, 2016, 1:45 AM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Queen Anne's County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 67 km from the middle of the area, began a volume at 01:48 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, 1.8 hours before the alert went out and 117 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: 851 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 1134 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 114 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

583 
WGUS81 KPHI 030147
FLSPHI

FLOOD ADVISORY
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
947 PM EDT MON MAY 2 2016

MDC035-041-030545-
/O.NEW.KPHI.FA.Y.0021.160503T0147Z-160503T0545Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
TALBOT MD-QUEEN ANNE'S MD-
947 PM EDT MON MAY 2 2016

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SMALL STREAM FLOOD ADVISORY FOR...
  TALBOT COUNTY IN EASTERN MARYLAND...
  SOUTHWESTERN QUEEN ANNE'S COUNTY IN NORTHEASTERN MARYLAND...

* UNTIL 145 AM EDT

* AT 946 PM EDT...DOPPLER RADAR INDICATED HEAVY RAIN DUE TO
  THUNDERSTORMS. THIS WILL CAUSE SMALL STREAM FLOODING IN THE
  ADVISORY AREA. UP TO TWO INCHES OF RAIN HAVE ALREADY FALLEN.
  ADDITIONAL HEAVY RAINFALL IS EXPECTED AS MORE RAIN MOVES ACROSS
  CHESAPEAKE BAY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...AS WELL AS FARM AND COUNTRY ROADS. DO NOT
ATTEMPT TO TRAVEL ACROSS FLOODED ROADS. FIND ALTERNATE ROUTES.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

&&

LAT...LON 3876 7633 3885 7627 3878 7621 3879 7619
      3889 7620 3889 7617 3887 7619 3888 7604
      3877 7597 3873 7601 3869 7598 3868 7620
      3876 7622 3872 7628 3871 7627 3872 7630
      3878 7629 3872 7633 3875 7637

$$

1 follow-up statement

889 
WGUS81 KPHI 030448
FLSPHI

FLOOD ADVISORY
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1248 AM EDT TUE MAY 3 2016

MDC035-041-030545-
/O.CON.KPHI.FA.Y.0021.000000T0000Z-160503T0545Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
TALBOT MD-QUEEN ANNE'S MD-
1248 AM EDT TUE MAY 3 2016

...THE SMALL STREAM FLOOD ADVISORY REMAINS IN EFFECT UNTIL 145 AM EDT
FOR TALBOT AND SOUTHWESTERN QUEEN ANNE'S COUNTIES...

AT 1244 AM EDT...DOPPLER RADAR AND AUTOMATED RAIN GAUGES INDICATED
THAT AROUND 2 TO 3 INCHES OF RAIN OCCURRED IN PORTIONS OF THE
ADVISORY AREA LATE MONDAY EVENING.  THE HEAVY RAINS HAVE SUBSIDED.
THERE MAY STILL BE SOME LEFTOVER FLOODING IN POOR DRAINAGE AREAS.  

MEANWHILE,  A FLASH FLOOD WARNING CONTINUES FROM EASTON MARYLAND
EASTWARD INTO SOUTHERN AND CENTRAL DELAWARE. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A FLOOD ADVISORY MEANS RIVER OR STREAM FLOWS ARE ELEVATED...OR PONDING
OF WATER IN URBAN OR OTHER AREAS IS OCCURRING OR IS IMMINENT.

&&

LAT...LON 3885 7627 3878 7621 3879 7619 3888 7620
      3889 7617 3887 7619 3884 7612 3872 7604
      3869 7606 3868 7620 3876 7622 3872 7630
      3878 7629 3876 7632 3872 7633 3873 7634
      3873 7635 3875 7635

$$

DRAG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 2, 8:37 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Queen Anne's, Talbot	68 min
May 2, 9:43 PM EDT	Special Weather Statement	PHI	Caroline, Queen Anne's	77 min
May 2, 10:15 PM EDT	Severe Thunderstorm Warning	PHI	Caroline	60 min
May 2, 10:22 PM EDT	Areal Flood Advisory	PHI	Caroline, Talbot	4 hr
May 2, 10:45 PM EDT	Flash Flood Warning	PHI	Caroline, Queen Anne's, Talbot	6 hr

Nearby

Areal Flood Advisories in Maryland, 2016 Every areal flood advisory in 2016

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.