Alert archive / Maryland / Flash Flood Warnings in 2018

Flash Flood Warning 42, NWS Philadelphia/Mount Holly

July 25, 2018Caroline County, Queen Anne's County, Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 25, 2018, 6:00 PM EDT for Caroline County, Queen Anne's County, Talbot County, Maryland. It was in force for 3 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
Jul 25, 2018, 6:00 PM EDT (22:00 UTC)
Expired
Jul 25, 2018, 9:17 PM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

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

The radar

The Dover AFB radar (KDOX), 52 km from the middle of the area, began a volume at 22:07 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 106 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 2018-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 161 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 2018-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -41 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
161 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
730 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-41 m²/s²
0-3 km storm-relative helicity
-26 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

988 
WGUS51 KPHI 252200
FFWPHI
MDC011-035-041-260200-
/O.NEW.KPHI.FF.W.0042.180725T2200Z-180726T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
600 PM EDT WED JUL 25 2018

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Talbot County in eastern Maryland...
  South central Queen Anne's County in northeastern Maryland...
  Southwestern Caroline County in eastern Maryland...

* Until 1000 PM EDT.

* At 559 PM EDT, Doppler radar indicated heavy rain across the warned
  area. Up to two inches of rain have already fallen. Flash flooding
  is expected to begin shortly in the areas of heaviest rain.

* Some locations that could experience flooding include...
  Easton, Ridgely, Trappe, Preston, Queen Anne, Tanyard, Harmony,
  Starr, Skipton, Jumptown, Matthews, Choptank, Wye Mills, Hambleton,
  Griffin, Windyhill, Cordova, Queenstown and Hillsboro.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3861 7608 3863 7608 3863 7611 3898 7619
      3900 7617 3901 7618 3903 7589 3870 7583
      3870 7590 3869 7590 3866 7596 3862 7598
      3860 7605

$$

Robertson
2 follow-up statements
848 
WGUS71 KPHI 252253
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
653 PM EDT WED JUL 25 2018

MDC011-035-041-260200-
/O.CON.KPHI.FF.W.0042.000000T0000Z-180726T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Talbot MD-Queen Anne's MD-Caroline MD-
653 PM EDT WED JUL 25 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1000 PM EDT FOR
TALBOT...SOUTH CENTRAL QUEEN ANNE'S AND SOUTHWESTERN CAROLINE
COUNTIES...

At 652 PM EDT, Doppler radar indicated moderate to heavy rain across 
the warned area. Up to two inches of rain have already fallen with 
additional rainfall expected. While the rain rates have dropped off, 
this additional rainfall is expected to continue the threat for 
flash flooding.

Some locations that could experience flooding include...
Easton, Ridgely, Trappe, Preston, Queen Anne, Tanyard, Harmony,
Starr, Skipton, Jumptown, Matthews, Choptank, Wye Mills, Hambleton,
Griffin, Windyhill, Cordova, Queenstown and Hillsboro.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 3861 7608 3863 7608 3863 7611 3898 7619
      3900 7617 3901 7618 3903 7589 3870 7583
      3870 7590 3869 7590 3866 7596 3862 7598
      3860 7605

$$

Robertson
074 
WGUS71 KPHI 260117
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
917 PM EDT WED JUL 25 2018

MDC011-035-041-260126-
/O.CAN.KPHI.FF.W.0042.000000T0000Z-180726T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Talbot MD-Queen Anne's MD-Caroline MD-
917 PM EDT WED JUL 25 2018

...THE FLASH FLOOD WARNING FOR TALBOT...SOUTH CENTRAL QUEEN ANNE'S
AND SOUTHWESTERN CAROLINE COUNTIES IS CANCELLED...

The heavy rain has ended for now across the area, and flash flooding 
is no longer expected to pose a threat. However, additional heavy 
rain is possible during this evening and overnight.

LAT...LON 3861 7608 3863 7608 3863 7611 3898 7619
      3900 7617 3901 7618 3903 7589 3870 7583
      3870 7590 3869 7590 3866 7596 3862 7598
      3860 7605

$$

Robertson

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 25, 1:57 PM EDTSpecial Weather StatementPHICaroline33 min
Jul 25, 2:29 PM EDTSpecial Weather StatementPHICaroline46 min
Jul 25, 3:16 PM EDTAreal Flood AdvisoryPHICaroline, Cecil, Kent, Queen Anne's4 hr
Jul 25, 4:34 PM EDTAreal Flood AdvisoryPHICecil2 hr
Jul 25, 5:17 PM EDTAreal Flood AdvisoryPHICaroline, Kent, Queen Anne's, Talbot4 hr

Nearby

Flash Flood Warnings in Maryland, 2018Every flash flood warning in 2018

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.