Alert archive / Maryland / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 18, NWS Philadelphia/Mount Holly

March 1, 2017Kent County, New Castle County, Sussex County, Delaware; 4 counties in Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Mar 1, 2017, 2:09 PM EST for Kent County, New Castle County, Sussex County, Delaware; 4 counties in Maryland. It was in force for 51 min. 15 reports 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
Mar 1, 2017, 2:09 PM EST (19:09 UTC)
Expired
Mar 1, 2017, 3:00 PM EST
In force
51 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
70.0 mph

Counties Kent County, DE, New Castle 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), 51 km from the middle of the area, began a volume at 19:12 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

TimeReportWhereRemark
Mar 1, 2:17 PM ESTMARINE TSTM WIND 485 Ese Bay Ridge, MD
Mar 1, 2:24 PM ESTTSTM WND GST 55Tolchester Beach, MD
Mar 1, 2:30 PM ESTTSTM WND DMGChurch Hill, MDNUMEROUS TREES REPORTED DOWN WITH A SHED ROOF DAMAGED.
Mar 1, 2:32 PM ESTMARINE TSTM WIND 4415 Ese Galesville, MD
Mar 1, 2:32 PM ESTTSTM WND DMGRoyal Oak, MDTREE AND WIRES DOWN IN ROYAL OAK
Mar 1, 2:35 PM ESTTSTM WND DMGEaston, MDTREE DOWN IN EASTON
Mar 1, 2:38 PM ESTTSTM WND DMGBarclay, MDTRACTOR TRAILER TRUCK FLIPPED OVER ON ROUTE 313. SEVERAL SPEED LIMIT SIGNS BLOWN DOWN AS WELL.
Mar 1, 2:42 PM ESTTSTM WND DMGRidgely, MDTREE DOWN IN RIDGELY
Mar 1, 2:44 PM ESTTSTM WND DMGGreensboro, MDTREE DOWN IN GREENSBORO
Mar 1, 2:45 PM ESTTSTM WND DMGDenton, MDTREE DOWN IN DENTON
Mar 1, 2:48 PM ESTTSTM WND DMGPreston, MDTREE DOWN IN PRESTON
Mar 1, 2:53 PM ESTTSTM WND DMGDover, DETREES REPORTED DOWN ON SEVERAL ROADWAYS IN DOVER.
Mar 1, 2:55 PM ESTTSTM WND DMG1 W Melvins Crossroads, DETWO STEEL BUILDINGS AND A HOME WERE DAMAGED FROM THUNDERSTORM WIND GUSTS. SEVERAL IRRIGATION PIVOTS OVERTURNED AND NUMEROUS LARGE TREES DOWNED. TIME ESTIMATED FROM RADAR.
Mar 1, 2:55 PM ESTTSTM WND DMGFelton, DETREES DOWN ON A ROADWAY IN FELTON.
Mar 1, 2:57 PM ESTTSTM WND DMGHarrington, DETREES DOWN ON ROADWAYS IN HARRINGTON.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Mar 1, 1:13 PM ESTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 7.2 hours before the alert went out and 71 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-pSkew-T log-p diagram, Phillips Aaf/Abe, MD at 12:00Z on 2017-03-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 12:00Z on 2017-03-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 212 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
624 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
212 m²/s²
0-3 km storm-relative helicity
284 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

121 
WUUS51 KPHI 011909
SVRPHI
DEC001-003-005-MDC011-029-035-041-012000-
/O.NEW.KPHI.SV.W.0018.170301T1909Z-170301T2000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
209 PM EST WED MAR 1 2017

The National Weather Service in Mount Holly NJ  has issued a

* Severe Thunderstorm Warning for...
  Western Sussex County in southern Delaware...
  Southwestern New Castle County in northern Delaware...
  Kent County in central Delaware...
  Talbot County in eastern Maryland...
  Queen Anne's County in northeastern Maryland...
  Caroline County in eastern Maryland...
  Kent County in northeastern Maryland...

* Until 300 PM EST

* At 208 PM EST, severe thunderstorms were located along a line
  extending from near Millers Island to near Annapolis to near Deale
  to near Prince Frederick to Sheridan Point to near Saint Clements
  Bay, moving east at 65 mph.

  HAZARD...70 mph wind gusts and quarter size hail. 

  SOURCE...Trained weather spotters. 

  IMPACT...Hail damage to vehicles is expected. Expect considerable 
           tree damage. Wind damage is also likely to mobile homes, 
           roofs, and outbuildings. 

* Locations impacted include...
  Dover, Easton, Centerville, Talbot, Smyrna, Seaford, Chestertown,
  Denton, Centreville, Laurel, Harrington, Camden, Clayton,
  Federalsburg, Bridgeville, Greensboro, Oakland, Ridgely, Cheswold
  and Rock Hall.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a DANGEROUS SITUATION. These storms are producing widespread 
wind damage. SEEK SHELTER NOW inside a sturdy structure and stay 
away from windows! This severe thunderstorm may contain little or no 
lightning. Do not wait until you hear thunder before taking cover.

&&

LAT...LON 3846 7569 3869 7577 3868 7593 3857 7604
      3876 7622 3877 7632 3867 7634 3896 7631
      3884 7637 3892 7637 3904 7631 3901 7622
      3917 7628 3932 7618 3938 7552 3879 7545
      3845 7558
TIME...MOT...LOC 1908Z 279DEG 55KT 3920 7639 3894 7649 3877 7659 3858
7662 3845 7664 3829 7673

HAIL...1.00IN
WIND...70MPH
 
$$

33
3 follow-up statements
381 
WWUS51 KPHI 011935
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
235 PM EST WED MAR 1 2017

DEC001-003-005-MDC011-029-035-041-012000-
/O.CON.KPHI.SV.W.0018.000000T0000Z-170301T2000Z/
Sussex DE-New Castle DE-Kent DE-Talbot MD-Queen Anne's MD-
Caroline MD-Kent MD-
235 PM EST WED MAR 1 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EST
FOR WESTERN SUSSEX...SOUTHWESTERN NEW CASTLE...KENT...TALBOT...QUEEN
ANNE'S...CAROLINE AND NORTHEASTERN KENT COUNTIES...

At 234 PM EST, severe thunderstorms were located along a line
extending from near Massey to Wye Mills to near Oxford to 7 miles
northwest of Taylors Island, moving east at 60 mph.

HAZARD...70 mph wind gusts. 

SOURCE...Radar and trained spotter indicated. This line of storms 
         has a history of producing damaging winds in northern 
         Virginia and central and southern Maryland.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings. 

Locations impacted include...
Dover, Easton, Centerville, Talbot, Smyrna, Seaford, Chestertown,
Denton, Centreville, Laurel, Harrington, Camden, Clayton,
Federalsburg, Bridgeville, Greensboro, Oakland, Ridgely, Delmar and
Cheswold.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This severe thunderstorm may contain little or no lightning. Do not
wait until you hear thunder before taking cover.

&&

LAT...LON 3846 7569 3864 7571 3869 7577 3868 7593
      3857 7604 3877 7629 3878 7629 3869 7634
      3882 7631 3886 7626 3879 7620 3879 7619
      3891 7625 3891 7620 3895 7622 3933 7598
      3938 7553 3878 7545 3846 7557 3845 7558
TIME...MOT...LOC 1934Z 256DEG 54KT 3931 7589 3893 7608 3870 7625 3857
7637

HAIL...<.75IN
WIND...70MPH
 
$$

JRK
214 
WWUS51 KPHI 011950
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
250 PM EST WED MAR 1 2017

MDC029-035-011959-
/O.CAN.KPHI.SV.W.0018.000000T0000Z-170301T2000Z/
Queen Anne's MD-Kent MD-
250 PM EST WED MAR 1 2017

...THE SEVERE THUNDERSTORM WARNING FOR QUEEN ANNE'S AND NORTHEASTERN
KENT COUNTIES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until 700 PM EST for
central, northern and southern Delaware...and eastern Maryland.

LAT...LON 3847 7569 3864 7571 3869 7577 3871 7584
      3870 7590 3866 7596 3857 7604 3859 7606
      3861 7607 3907 7575 3936 7567 3938 7553
      3877 7545 3871 7548 3846 7565
TIME...MOT...LOC 1949Z 269DEG 61KT 3932 7561 3894 7576 3868 7596 3859
7603

$$

DEC001-003-005-MDC011-041-012000-
/O.CON.KPHI.SV.W.0018.000000T0000Z-170301T2000Z/
Sussex DE-New Castle DE-Kent DE-Talbot MD-Caroline MD-
250 PM EST WED MAR 1 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EST
FOR WESTERN SUSSEX...SOUTH CENTRAL NEW CASTLE...KENT...SOUTHEASTERN
TALBOT AND CAROLINE COUNTIES...

At 249 PM EST, severe thunderstorms were located along a line
extending from Smyrna to near Greensboro to Choptank to near
Cambridge, moving east at 70 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar and trained spotter indicated. This line of storms 
         has a history of producing damaging winds in northern 
         Virginia and central and southern Maryland.

IMPACT...Expect damage to roofs, siding, and trees. 

Locations impacted include...
Dover, Smyrna, Seaford, Denton, Laurel, Harrington, Camden, Clayton,
Federalsburg, Bridgeville, Greensboro, Cheswold, Preston, Woodside,
Viola, Hartly, Smithville, Rising Sun-Lebanon, Hazlettville and
Agner.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This severe thunderstorm may contain little or no lightning. Do not
wait until you hear thunder before taking cover.

&&

LAT...LON 3847 7569 3864 7571 3869 7577 3871 7584
      3870 7590 3866 7596 3857 7604 3859 7606
      3861 7607 3907 7575 3936 7567 3938 7553
      3877 7545 3871 7548 3846 7565
TIME...MOT...LOC 1949Z 269DEG 61KT 3932 7561 3894 7576 3868 7596 3859
7603

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

JRK
035 
WWUS51 KPHI 012000
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
300 PM EST WED MAR 1 2017

DEC001-003-005-MDC011-041-012009-
/O.EXP.KPHI.SV.W.0018.000000T0000Z-170301T2000Z/
Sussex DE-New Castle DE-Kent DE-Talbot MD-Caroline MD-
300 PM EST WED MAR 1 2017

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN SUSSEX...SOUTH CENTRAL
NEW CASTLE...KENT...SOUTHEASTERN TALBOT AND CAROLINE COUNTIES WILL
EXPIRE AT 300 PM EST...
    
The storms which prompted the warning have moved out of the area.
Therefore the warning will be allowed to expire.

A Severe Thunderstorm Warning still remains in effect for 
southeastern Caroline County in Maryland and Kent and Sussex 
Counties in Delaware until 345 PM.

A severe thunderstorm watch remains in effect until 700 PM EST for
central, northern and southern Delaware...and eastern Maryland.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

LAT...LON 3847 7569 3864 7571 3869 7577 3871 7584
      3870 7590 3866 7596 3857 7604 3859 7606
      3861 7607 3907 7575 3936 7567 3938 7553
      3877 7545 3871 7548 3846 7565
TIME...MOT...LOC 1959Z 279DEG 55KT 3930 7545 3892 7560 3866 7580 3857
7587

$$

JRK

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 1, 2:00 PM ESTSevere Thunderstorm WarningPHINew Castle45 min
Mar 1, 2:45 PM ESTSevere Thunderstorm WarningPHIKent, New Castle, Sussex60 min
Mar 1, 3:09 PM ESTWind AdvisoryPHIKent, New Castle, Sussex19 hr
Mar 1, 2:46 PM ESTSpecial Weather StatementPHICecil29 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.