Alert archive / Maryland / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 107, NWS Philadelphia/Mount Holly

September 12, 2013Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 12, 2013, 6:21 PM EDT for Talbot County, Maryland. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 12, 2013, 6:21 PM EDT (22:21 UTC)
Expired
Sep 12, 2013, 7:00 PM EDT
In force
39 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

County Talbot County, MD

The radar

The Dover AFB radar (KDOX), 64 km from the middle of the area, began a volume at 22:24 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Sep 12, 2:50 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.4 hours before the alert went out and 80 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, Phillips Aaf/Abe, MD at 12:00Z on 2013-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1009 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, Phillips Aaf/Abe, MD at 12:00Z on 2013-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 square meters per square second.1939Sfc1 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
1009 J/kg
Mixed-layer CIN
-79 J/kg
Mixed-layer LCL
970 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
39 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.

604 
WUUS51 KPHI 122221
SVRPHI
MDC041-122300-
/O.NEW.KPHI.SV.W.0107.130912T2221Z-130912T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
621 PM EDT THU SEP 12 2013

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  TALBOT COUNTY IN EASTERN MARYLAND...

* UNTIL 700 PM EDT

* AT 620 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM. THE STORM WAS NEAR ST. MICHAELS...MOVING EAST
  AT 20 MPH. THIS STORM IS CAPABLE OF PRODUCING ONE INCH DIAMETER
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. 

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  COPPERVILLE AROUND 630 PM EDT...
  HAMBLETON AND TRAPPE AROUND 640 PM EDT...
  EASTON AROUND 645 PM EDT...
  SKIPTON AROUND 650 PM EDT...
  WINDYHILL AROUND 655 PM EDT...
  CORDOVA AROUND 700 PM EDT...

LAT...LON 3882 7632 3884 7625 3881 7621 3885 7620
      3892 7599 3878 7596 3873 7601 3867 7594
      3865 7595 3864 7618 3866 7617 3868 7623
      3873 7626 3870 7627 3872 7632 3879 7634
TIME...MOT...LOC 2221Z 259DEG 17KT 3874 7620

$$

FORECASTER: AMC
1 follow-up statement
595 
WWUS51 KPHI 122257
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
657 PM EDT THU SEP 12 2013

MDC041-122305-
/O.EXP.KPHI.SV.W.0107.000000T0000Z-130912T2300Z/
TALBOT MD-
657 PM EDT THU SEP 12 2013

...THE SEVERE THUNDERSTORM WARNING FOR TALBOT COUNTY WILL EXPIRE AT
700 PM EDT...

THE SEVERE THUNDERSTORM WARNING WILL BE ALLOWED TO EXPIRE.

ALTHOUGH NOT LIKELY TO BE SEVERE...SHOWERS AND THUNDERSTORMS WILL 
CONTINUE OVER THE AREA FOR A WHILE LONGER. RESIDENTS SHOULD EXERCISE 
APPROPRIATE CAUTION.

LAT...LON 3882 7632 3884 7625 3881 7621 3885 7620
      3892 7599 3878 7596 3873 7601 3867 7594
      3865 7595 3864 7618 3866 7617 3868 7623
      3873 7626 3870 7627 3872 7632 3879 7634
TIME...MOT...LOC 2255Z 259DEG 17KT 3877 7600

$$

FORECASTER: AMC

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 12, 2:21 PM EDTSpecial Weather StatementPHIKent, Queen Anne's54 min
Sep 12, 5:58 PM EDTSpecial Weather StatementPHIQueen Anne's, Talbot62 min
Sep 12, 6:40 PM EDTSpecial Weather StatementPHICaroline65 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2013Every severe thunderstorm 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.