Alert archive / Maryland / Severe Thunderstorm Warnings in 2017
Severe Thunderstorm Warning 175, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 18, 2017, 7:53 PM EDT for 4 counties in Maryland; Kent County, Sussex County, Delaware. It was in force for 48 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 18, 2017, 7:53 PM EDT (23:53 UTC)
- Expired
- Aug 18, 2017, 8:41 PM EDT
- In force
- 48 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Kent County, DE, Sussex County, DE, Caroline County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD
The radar
The Dover AFB radar (KDOX), 46 km from the middle of the area, began a volume at 23:52 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.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Aug 18, 2:27 PM EDT | Severe Thunderstorm Watch | SPC | 9 hr |
The nearest sounding before it
Wallops Is Stn, VA (KWAL), launched 12:00Z, 11.9 hours before the alert went out and 107 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.
- Mixed-layer CAPE
- 582 J/kg
- Mixed-layer CIN
- -57 J/kg
- Mixed-layer LCL
- 808 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 105 m²/s²
- 0-3 km storm-relative helicity
- 112 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
805
WUUS51 KPHI 182353
SVRPHI
DEC001-005-MDC011-029-035-041-190100-
/O.NEW.KPHI.SV.W.0175.170818T2353Z-170819T0100Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
753 PM EDT FRI AUG 18 2017
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Sussex County in southern Delaware...
Southern Kent County in central Delaware...
Talbot County in eastern Maryland...
Southern Queen Anne's County in northeastern Maryland...
Caroline County in eastern Maryland...
Southwestern Kent County in northeastern Maryland...
* Until 900 PM EDT
* At 752 PM EDT, severe thunderstorms were located along a line
extending from near St. Michaels to near Big Stone Beach, moving
southeast at 15 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Minor damage to vehicles is possible. Expect damage to
trees and power lines.
* Locations impacted include...
Dover, Easton, Georgetown, Centerville, Talbot, Milford, Seaford,
Denton, Centreville, Millsboro, Laurel, Harrington, Camden, Lewes,
Federalsburg, Milton, Bridgeville, Greensboro, Oakland and Ridgely.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
In addition to large hail and damaging winds...frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember...if you can hear thunder...you are close
enough to be struck by lightning.
&&
LAT...LON 3846 7569 3864 7571 3871 7584 3857 7604
3876 7622 3871 7628 3878 7629 3876 7632
3870 7634 3871 7634 3896 7631 3884 7637
3885 7638 3904 7631 3897 7622 3907 7621
3912 7537 3893 7529 3872 7505 3859 7504
TIME...MOT...LOC 2352Z 311DEG 14KT 3876 7619 3896 7537
HAIL...1.00IN
WIND...60MPH
$$
SFJ2 follow-up statements
190
WWUS51 KPHI 190016
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
816 PM EDT FRI AUG 18 2017
MDC029-035-190025-
/O.CAN.KPHI.SV.W.0175.000000T0000Z-170819T0100Z/
Queen Anne's MD-Kent MD-
816 PM EDT FRI AUG 18 2017
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN QUEEN ANNE'S AND
SOUTHWESTERN KENT COUNTIES IS CANCELLED...
The storms which prompted the warning have moved out of these
counties. Therefore, the warning has been cancelled.
A severe thunderstorm watch remains in effect until 1100 PM EDT for
central and southern Delaware...and eastern and northeastern
Maryland.
LAT...LON 3864 7571 3869 7577 3871 7584 3868 7593
3857 7604 3876 7622 3871 7628 3878 7629
3874 7632 3871 7634 3872 7634 3884 7627
3881 7621 3878 7621 3886 7619 3906 7537
3893 7529 3872 7505 3860 7504 3846 7569
TIME...MOT...LOC 0015Z 311DEG 14KT 3870 7610 3890 7528
$$
DEC001-005-MDC011-041-190100-
/O.CON.KPHI.SV.W.0175.000000T0000Z-170819T0100Z/
Sussex DE-Kent DE-Talbot MD-Caroline MD-
816 PM EDT FRI AUG 18 2017
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR SUSSEX...SOUTHERN KENT...TALBOT AND CAROLINE COUNTIES...
At 815 PM EDT, severe thunderstorms were located along a line
extending from near Hambleton to 7 miles south of Big Stone Beach,
moving southeast at 15 mph.
HAZARD...60 mph wind gusts and nickel size hail.
SOURCE...Radar indicated.
IMPACT...Expect damage to trees and power lines.
Locations impacted include...
Easton, Georgetown, Talbot, Milford, Seaford, Denton, Millsboro,
Laurel, Harrington, Lewes, Federalsburg, Milton, Bridgeville, Trappe,
St. Michaels, Preston, Ellendale, Queen Anne, Henlopen Acres and
Smithville.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3864 7571 3869 7577 3871 7584 3868 7593
3857 7604 3876 7622 3871 7628 3878 7629
3874 7632 3871 7634 3872 7634 3884 7627
3881 7621 3878 7621 3886 7619 3906 7537
3893 7529 3872 7505 3860 7504 3846 7569
TIME...MOT...LOC 0015Z 311DEG 14KT 3870 7610 3890 7528
HAIL...0.88IN
WIND...60MPH
$$
SFJ957
WWUS51 KPHI 190041
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
841 PM EDT FRI AUG 18 2017
DEC001-005-MDC011-041-190050-
/O.CAN.KPHI.SV.W.0175.000000T0000Z-170819T0100Z/
Sussex DE-Kent DE-Talbot MD-Caroline MD-
841 PM EDT FRI AUG 18 2017
...THE SEVERE THUNDERSTORM WARNING FOR SUSSEX...SOUTHERN KENT...
TALBOT AND CAROLINE COUNTIES IS CANCELLED...
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore the warning has been cancelled. However gusty winds,
heavy rain, and frequent lightning are still possible with these
thunderstorms.
A severe thunderstorm watch remains in effect until 1100 PM EDT for
central and southern Delaware...and eastern and northeastern
Maryland.
LAT...LON 3864 7571 3869 7577 3871 7584 3868 7593
3857 7604 3876 7622 3871 7628 3878 7629
3874 7632 3871 7634 3872 7634 3884 7627
3881 7621 3878 7621 3886 7619 3906 7537
3893 7529 3872 7505 3860 7504 3846 7569
TIME...MOT...LOC 0039Z 311DEG 14KT 3864 7601 3884 7519
$$
SFJThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 3:39 AM EDT | Flash Flood Watch | PHI | Caroline, Cecil, Kent, Queen Anne's, Talbot | 18 hr |
| Aug 18, 4:29 PM EDT | Severe Thunderstorm Warning | PHI | Cecil | 61 min |
| Aug 18, 4:57 PM EDT | Areal Flood Advisory | PHI | Cecil | 3 hr |
| Aug 18, 5:03 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 42 min |
| Aug 18, 5:39 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent | 66 min |
| Aug 18, 6:10 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 65 min |
| Aug 18, 6:12 PM EDT | Areal Flood Advisory | PHI | Cecil, Kent, Queen Anne's | 3 hr |
| Aug 18, 7:07 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 53 min |
| Aug 18, 7:33 PM EDT | Areal Flood Advisory | PHI | Caroline, Talbot | 3 hr |
| Aug 18, 5:20 PM EDT | Areal Flood Advisory | PHI | New Castle | 3 hr |
| Aug 18, 6:20 PM EDT | Special Weather Statement | PHI | Sussex | 25 min |
| Aug 18, 6:38 PM EDT | Special Weather Statement | PHI | New Castle | 37 min |
| Aug 18, 6:48 PM EDT | Special Weather Statement | PHI | New Castle | 27 min |
Nearby
Severe Thunderstorm Warnings in Maryland, 2017Severe Thunderstorm Warnings in Delaware, 2017Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.