LWX Listing of Tornadoes by County

     The following is a working document. All tornado data contained is accurate to the best of our knowledge, but may be incomplete. We are attempting to pull tornado historical data together from various sources to build one single data base of all tornadoes ever recorded in the Baltimore-Washington Forecast Office's area of responsibility. The tornadoes are listed in chronological order by county and by state. The counties are listed in alphabetical order. Virginia is listed first, followed by our counties in Maryland, the District of Columbia, and West Virginia. West Virginia data is largely missing at this point.

Click here to go directly to tornado events in Virginia, West Virginia, DC, Maryland.

All Listings are Alphabetical by state. The Fujita Damage Scale (F-Scale) is used to determine the tornado strength based on observed damage.  It is used throughout this document. The damage scale increases in intensity from a weak F0 (40 to 70 mph wind) to a F5 (over 260 mph wind). Click here to reference the Fujita Damage Scale for wind values and other associated information.  Many of the missing figures such as damages that are unknown at this time are continuing to be researched and data is filled in as it becomes available. If you come across any historical information that could add to this document and help us in this process, please forward it to barbara.watson@noaa.gov

(click here)  To get a summary of statistics by county without the tornado event details .

Summary Map of Tornadoes by County (all historically recorded tornadoes thru 1/1/00)

This is a historical look at patterns in the data. Nothing scientifically prevents a voilent tornado from striking any area, however, influences on storms by the mountainous terrain, the Chesapeake Bay and Tidal Potomac River, and large metropolitan areas is significant and effects the overall tornado climatology of the region.

Region 0: Dans Mountain and the Allegany Front is categorized with Garrett County which has a higher risk of strong tornadoes and more deaths and injuries. Tornado outbreaks that effect Garrett County, MD and Somerset County, PA historically have moved into the Frostburg area with results far different than tornadoes experienced east of here.
Region 1: East of the Allegany Front/Dans Mountain to the Shenandoah Mountains (west of the Shenandoah Valley). It includes the Potomac Highlands, the Allegeny Highlands, Morgan County and the rest of Allegany County, MD.
Region 2: The Shenandoah Valley of Virginia, Jefferson and Berkeley WV, and Washington County, MD.
Region 3: The central piedmont region of Virginia, northern Virginia, DC, and central Maryland (Carroll, Howard, Montgomery, and Frederick)
Region 4: Harford, Baltimore, Anne Arundel, Prince Georges, Southern Maryland, Stafford, Spotsylvania and King George Counties in Virginia.

These regions are not perfect. It would be better to draw the line between region 3 and 4 in Maryland along I-95 between Baltimore and Washington, but I do not have the data catologed in a way to not divide the data along county lines. Numbers have been adjusted for tornadoes crossing over county lines.

Data collected through June 1, 2001:

# Counties	Region #	Total # Tornadoes	#F0/F1	#F2/F3	%	#F4	Deaths	Injuries	Damages
1	0	5	4	2	40	1	0	5	$   5.2 M
8	1	10	9	1	8	0	0	5	$   0.3 M
10	2	60	42	18	30	0	5	29	$   5.6 M
17	3	141	94	47	33	0	28	338	$ 35.6 M
10	4	149	111	37	25	1	49	213	$ 33.3 M

Note: 30 of the deaths in Region 4 happened on the Tidal Potomac in 1 tornado in 1818.

Maryland (LWX portion) Tornadoes by Month

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Total
Weak (F0/F1)	2	2	4	6	15	25	36	21	13	13	12	0	144
Strong (F2+)	0	0	1	4	11	7	16	7	5	5	5	0	62
Total	2	2	5	10	26	32	52	28	18	18	17	0	206
% Strong	0	0	20	40	42	22	31	25	28	29	29	0	30

Virginia (LWX portion) Tornadoes by Month

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Total
Weak (F0/F1)	0	3	2	10	4	16	23	4	8	8	2	0	80
Strong (F2+)	1	0	0	5	7	4	4	8	9	3	3	0	44
Total	1	3	2	15	11	20	27	12	17	11	5	0	124
% Strong	100	0	0	33	64	20	15	67	53	27	60	0	35

The map below looks at tornadoes recorded by the National Weather Service since 1950 by county.  It also takes into account actual location of tornadoes and an attempt to analyze the data such to give a sense of the density or distribution of tornadoes across the area and show the comparative tornado risks.

December 30, 2005