Alert archive / Maryland / Tornado Watches in 2004
Tornado Watch 847
The Storm Prediction Center issued this tornado watch at Sep 28, 2004, 2:25 PM EDT for 5 states. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 28, 2004, 2:25 PM EDT (18:25 UTC)
- Expired
- Sep 28, 2004, 9:00 PM EDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
All 33 counties
Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Caroline County, MD, Cecil County, MD, City of Baltimore, MD, Harford County, MD, Howard County, MD, Kent County, MD, Prince George's County, MD, Queen Anne's County, MD, Talbot County, MD, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Ocean County, NJ, Salem County, NJ, Chester County, PA, Delaware County, PA, Philadelphia County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Manassas, VA, City of Manassas Park, VA, Fairfax County, VA, Prince William County, VA
Warnings issued inside it
18 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 28, 2:28 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore | 47 min |
| Sep 28, 2:36 PM EDT | Flash Flood Warning | PHI | Kent, New Castle | 3 hr |
| Sep 28, 3:14 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 46 min |
| Sep 28, 3:22 PM EDT | Flash Flood Warning | LWX | Fauquier, Prince William, City of Manassas, City of Manassas Park | 3 hr |
| Sep 28, 3:55 PM EDT | Flash Flood Warning | PHI | Chester, Delaware | 3 hr |
| Sep 28, 4:01 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 44 min |
| Sep 28, 4:11 PM EDT | Tornado Warning | PHI | New Castle | 34 min |
| Sep 28, 4:27 PM EDT | Flash Flood Warning | LWX | Baltimore, Carroll, Howard, City of Baltimore | 6 hr |
| Sep 28, 4:41 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 79 min |
| Sep 28, 4:44 PM EDT | Flash Flood Warning | LWX | Harford | 6 hr |
| Sep 28, 5:07 PM EDT | Flash Flood Warning | LWX | Fairfax, City of Fairfax | 4 hr |
| Sep 28, 5:11 PM EDT | Flash Flood Warning | PHI | Philadelphia | 3 hr |
| Sep 28, 5:30 PM EDT | Flash Flood Warning | PHI | Kent, New Castle, Sussex | 3 hr |
| Sep 28, 6:07 PM EDT | Flash Flood Warning | LWX | Fauquier, Prince William, City of Manassas, City of Manassas Park | 3 hr |
| Sep 28, 6:26 PM EDT | Flash Flood Warning | LWX | Anne Arundel, Prince George's | 3 hr |
| Sep 28, 6:38 PM EDT | Severe Thunderstorm Warning | PHI | Kent | 67 min |
| Sep 28, 6:47 PM EDT | Flash Flood Warning | PHI | Chester, Delaware | 3 hr |
| Sep 28, 8:05 PM EDT | Flash Flood Warning | PHI | New Castle | 6 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 6.4 hours before the alert went out and 34 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
- 95 J/kg
- Mixed-layer CIN
- -78 J/kg
- Mixed-layer LCL
- 631 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 109 m²/s²
- 0-3 km storm-relative helicity
- 172 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.4
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 281823
SEL7
SPC WW 281825
DCZ000-DEZ000-MDZ000-NJZ000-PAZ000-VAZ000-CWZ000-290100-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 847
NWS STORM PREDICTION CENTER NORMAN OK
225 PM EDT TUE SEP 28 2004
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
DISTRICT OF COLUMBIA
DELAWARE
EASTERN MARYLAND
SOUTHERN NEW JERSEY
SOUTHEAST PENNSYLVANIA
EXTREME NORTHERN VIRGINIA
COASTAL WATERS
EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 225 PM UNTIL 900
PM EDT.
TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE TORNADO WATCH AREA IS ALONG AND 70 STATUTE MILES EAST AND WEST
OF A LINE FROM 30 MILES SOUTHEAST OF WASHINGTON DISTRICT OF COLUM
TO 10 MILES WEST NORTHWEST OF LAKEHURST NEW JERSEY.
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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...CONTINUE...WW 846...
DISCUSSION...MOIST/UNSTABLE AIRMASS IS PRESENT FROM THE DC AREA
NORTHEASTWARD INTO SOUTHERN NJ. SCATTERED THUNDERSTORMS ARE
EXPECTED TO OVERSPREAD THIS REGION DURING THE AFTERNOON AS REMNANTS
OF JEANNE APPROACH FROM VA. FAVORABLE LOW LEVEL VERTICAL SHEAR
PROFILES ARE EXPECTED FOR A RISK OF ISOLATED TORNADOES.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 18035.
...HART
383,0775 400,0755 400,0731 383,0751SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 28, 8:56 AM EDT | Mesoscale Discussion | SPC | Sussex | 2 hr |
| Sep 28, 1:49 PM EDT | Mesoscale Discussion | SPC | Kent, New Castle, Sussex | 116 min |
| Sep 28, 4:36 PM EDT | Mesoscale Discussion | SPC | Kent, New Castle, Sussex | 114 min |
| Sep 28, 11:25 AM EDT | Tornado Watch | SPC | Calvert, Charles, Dorchester, Saint Mary's, Somerset, Wicomico and 1 more | 6 hr |
Nearby
Tornado Watches in Maryland, 2004Tornado Watches in New Jersey, 2004Tornado Watches in Virginia, 2004Every tornado watch in 2004
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.