Maryland, 1999

Damaging Winds and Heavy Rain in Maryland, September 29 to 30, 1999

September 29 to 30, 1999 · NWS LWX · 13 events in 8 counties and zones

An area of intense showers moved across much of Maryland from 10:00 PM EDT on the 29th through 2:00 AM EDT on the 30th, producing winds in excess of 55 MPH and very heavy downpours. Minor flooding was reported in a few locations, and high winds knocked numerous trees and power lines down.

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
$57,000
Crop damage
None recorded
Events
13

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS LWX wrote it up.

An area of intense showers moved across much of Maryland from 10:00 PM EDT on the 29th through 2:00 AM EDT on the 30th, producing winds in excess of 55 MPH and very heavy downpours. Minor flooding was reported in a few locations, and high winds knocked numerous trees and power lines down. In Washington County, high winds damaged 2 buildings on Willow Road in Hancock. Trees and power lines were downed from Clear Springs to Hagerstown. A wind gust of 51 MPH was recorded in Hagerstown at 11:53 PM EDT. Sharpsburg recorded 2.49 inches of rainfall. In Frederick County, rainfall amounts included 2.80 inches at Wolfsville, 2.5 inches at Thurmont, and 2.45 inches at Catoctin Mountain Park. Trees and power lines were downed in Libertytown, Urbana, Emmitsburg, Yellow Springs, Meyersville, Frederick, and Brunswick. 6000 county customers lost power as a direct result of the storm. Four roads were closed by fallen trees, and the MARC train was delayed by debris on the tracks in Brunswick. Trees and power lines were downed in Montgomery County, resulting in 6600 electrical outages. Trees blocked Route 108 at Brink Road in Damascus. Three trees were downed, loose items where thrown about, and leaves were plastered against one side of a home in Laytonsville. In Carroll County, winds gusted to 65 MPH in Westminster around 12:45 AM EDT. A wind gust of 53 MPH was recorded in Millers at around 1:00 AM EDT. A dozen large trees were downed in Tayneytown. Howard County reported downed trees and power outages near Route 32 and 39 in Columbia. In Prince George's County, 4200 customers lost power. Trees were downed in Mitchelsville around 1:00 AM EDT. Winds gusted to 43 MPH at Andrews Air Force Base at 1:03 AM EDT and 41 MPH at the University of Maryland in College Park. Oxon Hill reported 1.47 inches of rainfall. Anne Arundel County reported several downed trees in the northern half of the county. Winds gusted to 44 MPH at Baltimore/Washington International Airport (BWI) at 1:12 AM EDT. Annapolis reported 2.30 inches of rainfall and BWI received 1.16 inches. Over 60 trees and many power lines were downed in the city of Baltimore. 14,000 city customers lost power.

The radar

The Sterling radar (KLWX), 75 km away, was scanning. The volume nearest the first event began at 03:17 UTC.

Open the radar archive at this moment

Event by event

11 thunderstorm wind, 2 heavy rain. Local standard time, as filed.

Heavy Rain, Washington

When
September 29, 9:30 PM EST to 11:30 PM EST
Where
Washington County, Sharpsburg
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
39.604, -77.814 (the zone’s center; the record gives no point)

Over 2 inches in 2 hours

Heavy Rain, Frederick

When
September 29, 10:00 PM EST to 11:55 PM EST
Where
Frederick County, Countywide
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
39.472, -77.398 (the zone’s center; the record gives no point)

Over 2 inches in 2 hours

Thunderstorm Wind, Washington

When
September 29, 10:15 PM EST
Where
Washington County, Hancock
Property damage
$5,000
Reported by
FIRE DEPT/RESCUE SQUAD
Coordinates
39.700, -78.180

2 buildings damaged on Willow Road

Thunderstorm Wind, Washington

When
September 29, 10:35 PM EST to 10:50 PM EST
Where
Washington County, Clear Spg to Hagerstown
Property damage
$5,000
Reported by
NEWSPAPER
Coordinates
39.650, -77.930

Trees and power lines downed

Thunderstorm Wind, Frederick

When
September 29, 11:00 PM EST to 11:20 PM EST
Where
Frederick County, Countywide
Property damage
$10,000
Reported by
NEWSPAPER
Coordinates
39.470, -77.380

Numerous trees and power lines downed

Thunderstorm Wind, Montgomery

When
September 29, 11:30 PM EST
Where
Montgomery County, Laytonsville
Property damage
$500
Reported by
NEWSPAPER
Coordinates
39.220, -77.150

Tree downed

Thunderstorm Wind, Montgomery

When
September 29, 11:30 PM EST
Where
Montgomery County, Damascus
Property damage
$3,000
Reported by
TRAINED SPOTTER
Coordinates
39.280, -77.200

Several trees downed on Brink Road at Route 108

Thunderstorm Wind, Carroll

When
September 29, 11:45 PM EST
Where
Carroll County, Taneytown
Property damage
$3,000
Reported by
NEWSPAPER
Coordinates
39.670, -77.180

12 trees downed

Thunderstorm Wind, Carroll

When
September 29, 11:45 PM EST
Where
Carroll County, Westminster
Measured
52 kt (60 mph)
Reported by
TRAINED SPOTTER
Coordinates
39.580, -77.000

Estimated 60 MPH wind gust

Thunderstorm Wind, Prince George'S

When
September 30, 12:03 AM EST
Where
Prince George'S County, Mitchellville
Property damage
$2,000
Reported by
TRAINED SPOTTER
Coordinates
38.920, -76.750

4 feet diameter oak trees downed

Thunderstorm Wind, Howard

When
September 30, 12:05 AM EST
Where
Howard County, Columbia
Property damage
$3,000
Reported by
NEWSPAPER
Coordinates
39.230, -76.850

Power lines downed

Thunderstorm Wind, Baltimore City (C)

When
September 30, 12:25 AM EST
Where
Baltimore City (C) County, Baltimore
Property damage
$15,000
Reported by
NEWSPAPER
Coordinates
39.300, -76.620

60 trees downed

Thunderstorm Wind, Anne Arundel

When
September 30, 12:30 AM EST
Where
Anne Arundel County, North Portion
Property damage
$10,000
Reported by
TRAINED SPOTTER
Coordinates
39.130, -76.630

Several trees downed, concentrated in the Annapolis area

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.
Thunderstorm Wind
Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Maryland in 1999Every state in 1999This day in weather historyWarnings in Maryland, September 1999

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5718294, 5718296, 5718292, 5718293, 5718295, 5718297, 5718298, 5718299, 5718300, 5718301, 5718302, 5718303, 5716558.