Alert archive / Maryland / Severe Thunderstorm Watches in 2000

Severe Thunderstorm Watch 459

June 15, 20004 states

The Storm Prediction Center issued this severe thunderstorm watch at Jun 15, 2000, 7:45 PM EDT for 4 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jun 15, 2000, 7:45 PM EDT (23:45 UTC)
Expired: Jun 16, 2000, 1:00 AM EDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 41 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, MD, Dorchester County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Saint Mary's County, MD, Talbot County, MD, Wicomico County, MD, Worcester County, MD, Atlantic County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Manassas, VA, City of Manassas Park, VA, Fairfax County, VA, King George County, VA, Prince William County, VA, Spotsylvania County, VA, Stafford County, VA, Westmoreland County, VA

The radar

The Sterling radar (KLWX), 87 km from the middle of the area, began a volume at 23:45 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.

Warnings issued inside it

4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jun 15, 8:26 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel	49 min
Jun 15, 8:37 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Queen Anne's	38 min
Jun 15, 8:37 PM EDT	Severe Thunderstorm Warning	PHI	Talbot	38 min
Jun 15, 10:29 PM EDT	Severe Thunderstorm Warning	AKQ	Essex, King and Queen, Middlesex, Westmoreland	31 min

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 11.8 hours before the alert went out and 79 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: 59 J/kg
Mixed-layer CIN: -184 J/kg
Mixed-layer LCL: 598 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 91 m²/s²
0-3 km storm-relative helicity: 103 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

615 
WWUS9 KMKC 152333
SEL9  
MKC WW 152333
DCZ000-DEZ000-MDZ000-NJZ000-VAZ000-160500-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 459
STORM PREDICTION CENTER NORMAN OK
733 PM EDT THU JUN 15 2000

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   DISTRICT OF COLUMBIA
   DELAWARE                           
   CENTRAL AND EASTERN MARYLAND                           
   SOUTHERN NEW JERSEY                         
   NORTHERN AND EASTERN VIRGINIA                           

EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 745 PM UNTIL
100 AM EDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 75 STATUTE MILES
EAST AND WEST OF A LINE FROM 20 MILES SOUTHWEST OF PATUXENT RIVER
MARYLAND TO 10 MILES NORTH OF WILMINGTON DELAWARE.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...THIS SEVERE THUNDERSTORM WATCH REPLACES
SEVERE THUNDERSTORM WATCH NUMBER 456.  WATCH NUMBER 456 WILL NOT BE
IN EFFECT AFTER 745 PM EDT.  CONTINUE...WW 457...WW 458...

DISCUSSION...CONVECTIVE SYSTEM NOW APPROACHING THE DC/BALTIMORE
AREA HAS A LONG HISTORY...EXTENDING BACK TO NERN KY EARLIER TODAY. 
THIS...COUPLED WITH MODERATE WSW SHEAR PRESENT ACROSS REGION...
SUGGESTS THAT SYSTEM WILL REMAIN STRONG AS IT CONTINUES EWD ALONG
NRN FRINGE OF SURFACE-BASED INSTABILITY AXIS ACROSS MD/VA THROUGH
THE EVENING.   

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM
MOTION VECTOR 25030.

...CORFIDI

394,0741 380,0751 380,0780 394,0770

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 15, 12:30 PM EDT	Severe Thunderstorm Watch	SPC	Allegany, Garrett	6 hr
Jun 15, 2:15 PM EDT	Severe Thunderstorm Watch	SPC	Baltimore, Carroll, Frederick, Howard, Montgomery, Prince George's and 2 more	6 hr
Jun 15, 6:00 PM EDT	Severe Thunderstorm Watch	SPC	Charles	5 hr
Jun 15, 1:30 PM EDT	Severe Thunderstorm Watch	SPC	Alleghany, Amherst, Augusta, Bath, Bedford, Bland and 40 more	6 hr

Nearby

Severe Thunderstorm Watches in Maryland, 2000 Severe Thunderstorm Watches in Virginia, 2000 Severe Thunderstorm Watches in New Jersey, 2000 Every severe thunderstorm watch in 2000

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.