Alert archive / Maryland / Special Weather Statements in 2017

Special Weather Statement, NWS Philadelphia/Mount Holly

August 12, 2017Wicomico County, Maryland

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 12, 2017, 12:41 AM EDT for Wicomico County, Maryland. It was in force for 34 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: Aug 12, 2017, 12:41 AM EDT (04:41 UTC)
Expired: Aug 12, 2017, 1:15 AM EDT
In force: 34 min
Issued by: NWS Philadelphia/Mount Holly

County Wicomico County, MD

The radar

The Dover AFB radar (KDOX), 32 km from the middle of the area, began a volume at 04:43 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, 4.7 hours before the alert went out and 83 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.

149 
WWUS81 KPHI 120441
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
1241 AM EDT SAT AUG 12 2017

DEZ003-MDZ020-120515-
Inland Sussex-Caroline-
1241 AM EDT SAT AUG 12 2017

...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN SUSSEX AND
SOUTHEASTERN CAROLINE COUNTIES...

At 1240 AM EDT, a strong thunderstorm was located near Hurlock,
moving east at 25 mph.

Wind gusts up to 40 mph are possible with this storm.

Heavy rainfall is also occurring with this storm...and may cause 
ponding on roadways and poor drainage areas. Do not drive your 
vehicle through flooded roadways.

Frequent lightning is occurring with this storm. Lightning can strike 
10 miles away from a thunderstorm. Seek a safe shelter inside a 
building or vehicle.

Locations impacted include...
Seaford, Laurel, Federalsburg, Bridgeville, Delmar, Agner, Sycamore,
Blades and Bethel.

LAT...LON 3846 7569 3864 7571 3869 7577 3868 7578
      3868 7580 3870 7580 3870 7586 3877 7586
      3877 7544 3845 7543
TIME...MOT...LOC 0440Z 271DEG 20KT 3862 7578 

$$

Robertson

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 11:05 PM EDT	Areal Flood Advisory	PHI	Sussex, Warren	5 hr
Aug 11, 10:49 PM EDT	Special Weather Statement	PHI	Berks, Lehigh, Northampton	41 min
Aug 12, 5:00 PM EDT	Special Weather Statement	PHI	Berks	60 min
Aug 12, 5:24 PM EDT	Severe Thunderstorm Warning	PHI	Berks	51 min
Aug 12, 5:39 PM EDT	Areal Flood Advisory	PHI	Berks	4 hr
Aug 12, 6:18 PM EDT	Special Weather Statement	PHI	Chester	27 min
Aug 12, 7:10 PM EDT	Special Weather Statement	PHI	Chester	50 min
Aug 11, 10:53 PM EDT	Special Weather Statement	PHI	Talbot	37 min
Aug 11, 11:11 PM EDT	Severe Thunderstorm Warning	PHI	Talbot	49 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, 12:25 PM EDT	Areal Flood Advisory	PHI	Caroline	4 hr
Aug 12, 1:26 AM EDT	Special Weather Statement	PHI	Sussex	34 min
Aug 12, 1:54 AM EDT	Special Weather Statement	PHI	Sussex	51 min
Aug 12, 2:03 AM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Aug 12, 5:25 AM EDT	Special Weather Statement	PHI	Sussex	50 min
Aug 12, 5:55 AM EDT	Areal Flood Advisory	PHI	Sussex	2 hr
Aug 12, 10:37 AM EDT	Areal Flood Advisory	PHI	Sussex	4 hr

Nearby

Special Weather Statements in Maryland, 2017 Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.