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Severe Thunderstorm Warning

Severe Thunderstorm Warning

Severe Thunderstorm Warning
National Weather Service Baltimore MD/Washington DC
443 PM EDT Wed Jul 17 2019

The National Weather Service in Sterling Virginia has issued a

* Severe Thunderstorm Warning for...
  Montgomery County in central Maryland...
  Southeastern Frederick County in north central Maryland...
  Eastern Loudoun County in northern Virginia...
  North central Fairfax County in northern Virginia...

* Until 530 PM EDT.

* At 442 PM EDT, a severe thunderstorm was located over Lansdowne,
  moving east at 35 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Damaging winds will cause some trees and large branches
           to fall. This could injure those outdoors, as well as
           damage homes and vehicles. Roadways may become blocked by
           downed trees. Localized power outages are possible.
           Unsecured light objects may become projectiles.

* Locations impacted include...
  Germantown, Rockville, Gaithersburg, Reston, Leesburg, Herndon,
  Damascus, Broadlands, Lansdowne, Lowes Island, Brambleton,
  Poolesville, Aspen Hill, Potomac, North Bethesda, Ashburn,
  Montgomery Village, Sterling, North Potomac and Redland.


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


LAT...LON 3895 7751 3919 7761 3939 7722 3903 7706
TIME...MOT...LOC 2042Z 252DEG 25KT 3911 7749




Hazardous Weather Outlook

Hazardous Weather Outlook
National Weather Service Baltimore MD/Washington DC
435 PM EDT Wed Jul 17 2019

Chesapeake Bay north of Pooles Island MD-
Chesapeake Bay from Pooles Island to Sandy Point MD-
Chesapeake Bay from Sandy Point to North Beach MD-
Chesapeake Bay from North Beach to Drum Point MD-
Chesapeake Bay from Drum Point MD to Smith Point VA-
Tidal Potomac from Key Bridge to Indian Head MD-
Tidal Potomac from Indian Head to Cobb Island MD-
Tidal Potomac from Cobb Island MD to Smith Point VA-
Patapsco River including Baltimore Harbor-
Chester River to Queenstown MD-Eastern Bay-
Choptank River to Cambridge MD and the Little Choptank River-
Patuxent River to Broomes Island MD-
Tangier Sound and the inland waters surrounding Bloodsworth
Island-District of Columbia-Southern Baltimore-Prince Georges-
Anne Arundel-Charles-St. Marys-Calvert-Southeast Harford-
Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-Spotsylvania-
King George-
435 PM EDT Wed Jul 17 2019

This Hazardous Weather Outlook is for the Maryland portion of the
Chesapeake Bay, Tidal Potomac River, and adjacent counties in
central Maryland and northern Virginia as well as the District of

.DAY ONE...Tonight

A Heat Advisory is in effect for the entire area from until 8 PM
this evening.

Thunderstorms will be capable of producing damaging wind gusts
late this afternoon and evening. The strongest storms are most
likely in the Washington Metropolitan area between 5 PM and 6 PM,
and the Baltimore Metro area between 5:30 PM and 7 PM. Localized
flooding is possible from heavy rain associated with thunderstorms
during this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Heat indices may approach 105 degrees Thursday afternoon.

Dangerous heat and humidity are likely Friday through Sunday
across the entire area. Heat indices of 110 to 115 degrees are
possible during the afternoon and evening hours each day, and heat
indices may hold in the 80s and 90s at night. If the prolonged
heat and humidity is realized, it will become a significant threat
to anyone exposed to the heat for an extended period of time.


Please report any wind damage to the National Weather Service.


Heat Advisory

National Weather Service Baltimore MD/Washington DC
1133 AM EDT Wed Jul 17 2019

District of Columbia-Southern Baltimore-Prince Georges-
Anne Arundel-Charles-St. Marys-Calvert-
Central and Southeast Montgomery-Central and Southeast Howard-
Southeast Harford-Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-Spotsylvania-
King George-
Including the cities of Washington, Baltimore, Bowie,
Suitland-Silver Hill, Clinton, College Park, Greenbelt, Laurel,
Camp Springs, Glen Burnie, Annapolis, Severn, South Gate,
Severna Park, Arnold, Odenton, St. Charles, Waldorf,
Lexington Park, California, Chesapeake Beach, Huntingtown,
Dunkirk, North Beach, Lusby, Prince Frederick, Bethesda,
Rockville, Gaithersburg, Silver Spring, Columbia, Ellicott City,
Aberdeen, Dale City, Manassas, Woodbridge, Lake Ridge, Montclair,
Reston, Herndon, Annandale, Centreville, Chantilly, McLean,
Franconia, Arlington, Alexandria, Falls Church, Falmouth,
Fredericksburg, and Dahlgren
1133 AM EDT Wed Jul 17 2019


* HEAT INDEX VALUES...Between 105 and 109 due to temperatures in
  the mid 90s, and dewpoints in the lower 70s.

* IMPACTS...The heat and humidity may cause heat stress during
  outdoor exertion or extended exposure.


A Heat Advisory means that a period of high temperatures is
expected. The combination of high temperatures and high humidity
will create a situation in which heat illnesses are possible.

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear light weight and loose fitting clothing when
possible and drink plenty of water.

To reduce risk during outdoor work, the Occupational Safety and
Health Administration recommends scheduling frequent rest breaks
in shaded or air conditioned environments. Anyone overcome by
heat should be moved to a cool and shaded location. Heat stroke
is an emergency - call 911.



U.S. Dept. of Commerce
NOAA National Weather Service
1325 East West Highway
Silver Spring, MD 20910
Page last modified: May 16, 2007
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