Alert archive / Maryland / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 159, NWS Philadelphia/Mount Holly

August 11, 2017Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 11, 2017, 11:11 PM EDT for Talbot County, Maryland. It was in force for 49 min. 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 11, 2017, 11:11 PM EDT (03:11 UTC)
Expired: Aug 12, 2017, 12:00 AM EDT
In force: 49 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

County Talbot County, MD

The radar

The Dover AFB radar (KDOX), 70 km from the middle of the area, began a volume at 03:11 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 11, 11:59 PM EDT	TSTM WND DMG	1 W Trappe, MD	A TREE WAS TAKEN DOWN BY THUNDERSTORM WINDS ONTO WIRES.

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 00:00Z, 3.2 hours before the alert went out and 115 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: 50 J/kg
Mixed-layer CIN: -59 J/kg
Mixed-layer LCL: 692 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 68 m²/s²
0-3 km storm-relative helicity: 126 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

674 
WUUS51 KPHI 120311
SVRPHI
MDC041-120400-
/O.NEW.KPHI.SV.W.0159.170812T0311Z-170812T0400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1111 PM EDT FRI AUG 11 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Central Talbot County in eastern Maryland...

* Until midnight EDT

* At 1111 PM EDT, a severe thunderstorm was located near Tilghman
  Island, or 9 miles east of Breezy Point, moving northeast at 15
  mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* This severe thunderstorm will be near,
  Tilghman Island around 1125 PM EDT. 
  Talbot around 1140 PM EDT. 
  St. Michaels and Oxford around 1145 PM EDT. 
  Copperville around 1200 AM EDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3876 7633 3885 7627 3878 7621 3884 7617
      3857 7602 3863 7608 3864 7615 3868 7617
      3868 7621 3871 7624 3876 7622 3878 7630
      3867 7634 3874 7634 3876 7638
TIME...MOT...LOC 0311Z 245DEG 15KT 3867 7636 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

Robertson

1 follow-up statement

588 
WWUS51 KPHI 120339
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1139 PM EDT FRI AUG 11 2017

MDC041-120400-
/O.CON.KPHI.SV.W.0159.000000T0000Z-170812T0400Z/
Talbot MD-
1139 PM EDT FRI AUG 11 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT EDT
FOR SOUTH CENTRAL TALBOT COUNTY...

At 1139 PM EDT, a severe thunderstorm was located near Oxford, or 9
miles northwest of Cambridge, moving east at 20 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to trees and power lines. 

This severe storm will be near...
  Oxford around 1145 PM EDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3876 7623 3878 7621 3879 7621 3884 7617
      3857 7602 3863 7608 3864 7615 3868 7617
      3868 7621 3871 7624 3876 7622
TIME...MOT...LOC 0339Z 274DEG 17KT 3865 7621 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

Robertson

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 10:53 PM EDT	Special Weather Statement	PHI	Talbot	37 min
Aug 11, 11:16 PM EDT	Tornado Warning	PHI	Talbot	44 min
Aug 11, 11:31 PM EDT	Areal Flood Advisory	PHI	Caroline, Talbot	4 hr
Aug 11, 11:53 PM EDT	Tornado Warning	PHI	Talbot	37 min
Aug 12, 12:41 AM EDT	Special Weather Statement	PHI	Wicomico	34 min
Aug 12, 12:25 PM EDT	Areal Flood Advisory	PHI	Caroline	4 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2017 Every severe thunderstorm warning in 2017

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.