Alert archive / Maryland / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 13, NWS Baltimore/Washington
NWS Baltimore/Washington issued this severe thunderstorm warning at Apr 11, 2021, 9:16 PM EDT for Cecil County, Harford County, Maryland. It was in force for 44 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
- Apr 11, 2021, 9:16 PM EDT (01:16 UTC)
- Expired
- Apr 11, 2021, 10:00 PM EDT
- In force
- 44 min
- Issued by
- NWS Baltimore/Washington
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Cecil County, MD, Harford County, MD
The radar
The Dover AFB radar (KDOX), 112 km from the middle of the area, began a volume at 01:16 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 00:00Z, 1.3 hours before the alert went out and 129 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
- 154 J/kg
- Mixed-layer CIN
- -40 J/kg
- Mixed-layer LCL
- 2014 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- 57 m²/s²
- 0-3 km storm-relative helicity
- 58 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
620
WUUS51 KLWX 120116
SVRLWX
MDC015-025-120200-
/O.NEW.KLWX.SV.W.0013.210412T0116Z-210412T0200Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Baltimore MD/Washington DC
916 PM EDT Sun Apr 11 2021
The National Weather Service in Sterling Virginia has issued a
* Severe Thunderstorm Warning for...
Northeastern Harford County in northern Maryland...
Northwestern Cecil County in northeastern Maryland...
* Until 1000 PM EDT.
* At 916 PM EDT, a severe thunderstorm was located near Conowingo, or
11 miles northwest of Havre De Grace, moving northeast at 15 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Damaging winds will cause some trees and large branches
to fall. This could injure those outdoors, as well as
damage homes and vehicles. Roadways may become blocked by
downed trees. Localized power outages are possible.
Unsecured light objects may become projectiles.
* Locations impacted include...
Rising Sun, Rock Springs, Octoraro, Richardsmere, Conowingo and
Darlington.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3954 7616 3969 7631 3972 7630 3972 7606
TIME...MOT...LOC 0116Z 209DEG 14KT 3968 7625
HAIL...1.00IN
WIND...60MPH
$$
BJL1 follow-up statement
268
WWUS51 KLWX 120140
SVSLWX
Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
940 PM EDT Sun Apr 11 2021
MDC015-025-120200-
/O.CON.KLWX.SV.W.0013.000000T0000Z-210412T0200Z/
Harford MD-Cecil MD-
940 PM EDT Sun Apr 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM EDT
FOR NORTHEASTERN HARFORD AND NORTHWESTERN CECIL COUNTIES...
At 940 PM EDT, a severe thunderstorm was located over Conowingo, or 9
miles north of Havre De Grace, moving northeast at 10 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Damaging winds will cause some trees and large branches to
fall. This could injure those outdoors, as well as damage
homes and vehicles. Roadways may become blocked by downed
trees. Localized power outages are possible. Unsecured
light objects may become projectiles.
Locations impacted include...
Rising Sun, Rock Springs, Octoraro, Richardsmere and Conowingo.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3961 7612 3963 7618 3969 7623 3971 7629
3972 7630 3972 7606
TIME...MOT...LOC 0140Z 230DEG 10KT 3968 7617
HAIL...1.00IN
WIND...60MPH
$$
BJLThe office that day
Everything else NWS Baltimore/Washington issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 11, 9:01 PM EDT | Severe Thunderstorm Warning | LWX | Cecil, Harford | 44 min |
| Apr 11, 10:03 PM EDT | Areal Flood Warning | LWX | Cecil, Harford | 2 hr |
| Apr 11, 10:18 PM EDT | Areal Flood Warning | LWX | Cecil, Harford | 2 hr |
Nearby
Severe Thunderstorm Warnings in Maryland, 2021Every severe thunderstorm warning in 2021
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.