Alert archive / Maryland / Special Weather Statements in 2017

Special Weather Statement, NWS Philadelphia/Mount Holly

July 23, 2017Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this special weather statement at Jul 23, 2017, 5:47 PM EDT for Cecil County, Maryland. It was in force for 28 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: Jul 23, 2017, 5:47 PM EDT (21:47 UTC)
Expired: Jul 23, 2017, 6:15 PM EDT
In force: 28 min
Issued by: NWS Philadelphia/Mount Holly

County Cecil County, MD

The radar

The Dover AFB radar (KDOX), 93 km from the middle of the area, began a volume at 21:50 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.8 hours before the alert went out and 137 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: 186 J/kg
Mixed-layer CIN: -43 J/kg
Mixed-layer LCL: 983 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 31 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

966 
WWUS81 KPHI 232147
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
547 PM EDT SUN JUL 23 2017

MDZ008-232215-
Cecil-
547 PM EDT SUN JUL 23 2017

...A STRONG THUNDERSTORM WILL AFFECT EASTERN CECIL COUNTY...

At 546 PM EDT, a strong thunderstorm was located near Charlestown, or
near Havre De Grace, moving east at 15 mph.

Locations impacted include...
Elkton, North East, Charlestown, Cherry Hill, Cayots, Bay View,
Hollywood Beach, Woodlawn, Perryville and Chesapeake City.

These storms will contain gusty winds up to 40 mph, torrential 
downpours and occasional cloud to ground lightning.  

Locally heavy rainfall will lead to ponding of water on roadways and 
poor visibility at times this afternoon. Poor drainage flooding 
could also develop. 

Lightning can strike 10 miles away from a thunderstorm. Seek a safe 
shelter inside a building or vehicle.

LAT...LON 3964 7608 3967 7585 3943 7578 3941 7602
      3943 7599 3946 7601 3952 7598 3955 7603
      3955 7608 3959 7611
TIME...MOT...LOC 2146Z 261DEG 12KT 3951 7602 

$$

JRK

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 22, 8:05 PM EDT	Special Weather Statement	PHI	Ocean	25 min
Jul 22, 10:52 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	4 hr
Jul 23, 12:01 AM EDT	Coastal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Cumberland, Middlesex, Monmouth and 1 more	25 hr
Jul 23, 3:16 PM EDT	Flash Flood Watch	PHI	Burlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 6 more	15 hr
Jul 23, 3:43 PM EDT	Special Marine Warning	PHI		92 min
Jul 23, 4:29 PM EDT	Severe Thunderstorm Warning	PHI	Cape May, Cumberland	26 min
Jul 23, 4:39 PM EDT	Areal Flood Advisory	PHI	Cape May, Cumberland, Salem	4 hr
Jul 23, 4:40 PM EDT	Special Marine Warning	PHI		65 min
Jul 23, 4:26 PM EDT	Areal Flood Advisory	PHI	Chester	3 hr
Jul 23, 4:48 PM EDT	Areal Flood Advisory	PHI	Chester, Delaware	4 hr
Jul 23, 5:22 PM EDT	Special Weather Statement	PHI	Delaware	23 min
Jul 23, 6:08 PM EDT	Special Weather Statement	PHI	Delaware	37 min
Jul 23, 6:53 PM EDT	Flash Flood Warning	PHI	Chester, Delaware	14 hr
Jul 23, 7:20 PM EDT	Flash Flood Warning	PHI	Berks, Chester, Montgomery	6 hr
Jul 23, 7:41 PM EDT	Flash Flood Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	6 hr
Jul 22, 10:18 PM EDT	Special Weather Statement	PHI	Caroline, Talbot	72 min
Jul 22, 11:26 PM EDT	Areal Flood Advisory	PHI	Caroline, Queen Anne's, Talbot	4 hr
Jul 23, 2:38 PM EDT	Special Weather Statement	PHI	Caroline, Kent, Queen Anne's, Talbot	67 min
Jul 23, 2:47 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Queen Anne's, Talbot	43 min
Jul 23, 2:53 PM EDT	Special Weather Statement	PHI	Cecil	52 min
Jul 23, 3:27 PM EDT	Special Weather Statement	PHI	Cecil	33 min
Jul 23, 3:31 PM EDT	Special Weather Statement	PHI	Dorchester	44 min
Jul 23, 3:53 PM EDT	Areal Flood Advisory	PHI	Cecil, Kent	4 hr
Jul 23, 5:40 PM EDT	Areal Flood Advisory	PHI	Cecil	4 hr
Jul 23, 6:22 PM EDT	Special Weather Statement	PHI	Cecil	38 min
Jul 23, 6:26 PM EDT	Flash Flood Warning	PHI	Cecil	4 hr
Jul 22, 11:11 PM EDT	Special Weather Statement	PHI	Sussex	64 min
Jul 23, 4:15 PM EDT	Special Weather Statement	PHI	New Castle	30 min
Jul 23, 4:21 PM EDT	Areal Flood Advisory	PHI	Kent	3 hr
Jul 23, 4:44 PM EDT	Special Weather Statement	PHI	New Castle	16 min

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.