Severe Weather and Tornadoes Tips

 

The season for severe thunderstorms begins in the spring and lasts through hurricane season.  Thunderstorms develop in warm moist air in advance of eastward-moving cold fronts.   Tornadoes in the winter and early spring are often associated with strong, frontal systems that form in the Central States and move east.   Tornadoes can form in hurricanes therefore the threat along the Virginia coast last until hurricane season ends the end of November. 

A tornado on the York River or the Chesapeake Bay is called a waterspout.  Sometimes they move on shore and cause damage and injuries.

Click to see waterspout off Florida Keys.  Photographed from aircraft

Photo Date:  September 10, 1969

Dr Joseph Golden, NOAA

NOAA CENTRAL LIBRARY, Historical National Weather Service Collection

TORNADO FACTS for EMERGENCY ACTIONS 

Tornadoes come in various shapes, sizes, and strength.

Weak tornadoes (winds less than 110 mph) represent 69% of all tornadoes and cause less than 5%of deaths. 

Strong tornadoes (winds 110 - 205 mph) represent 29% of all tornadoes and cause 30% of all tornado deaths.  

Violent Tornadoes (winds greater than 205 mph) represent 2% of all tornadoes and cause 70% of all tornado deaths.

No place is safe from tornadoes including areas near rivers, lakes, and mountains. Opening windows to equalize pressure and minimize damage has NO effect on a structure.  Instead go to an internal, first floor safe area in the structure or to basement.

Tornadoes occur at any time of the year.

Tornadoes typically occur in the southern states, March through May and in the northern states during the summer months.

The hours between 3 and 9 p.m. appears to be the peak time for tornadoes, but they can occur at any time during the day.

Usually tornadoes move from southwest to northeast at an average speed of 30 mph.  Yet, there can be variations in direction and speed.  Some have been identified with a forward motion of  70 mph.

Who's most at risk:

People in automobiles

Elderly, very young, and the physically or cognitively impaired.

People in mobile homes

People who may not understand the warning due to a language barrier.

LISTEN and LOOK

During periods of severe weather listen to a radio or even better use a NOAA weather radio for special weather messages.  Weather terms that everyone needs to be familiar with include:

 

Tornado Watch:  Tornadoes are possible in your area.  Remain alert for approaching storms.

 

Tornado Warning:  A tornado has been sighted or indicated by weather radar.  If a tornado warning is issued for your area and the sky becomes threatening, move to your pre-designated place of safety.

 

Severe Thunderstorm Watch:  Severe thunderstorms are possible in your area.

 

Severe Thunderstorm Warning:  Severe thunderstorms are occurring.

 

During periods of severe weather, mother nature can provide some of the following warning signals that life-threatening weather is approaching: 

 

Dark greenish sky

Wall cloud

Large hail

A loud roar, similar to a freight train.  

 

Often and especially in this part of the country, tornadoes develop without much warning.  It is important to monitor the weather and be observant for environmental signals of impending danger.  Don't second guess the weather, take cover to be safe. 

Safety Actions  

Pre-designate a safe area on the first floor or basement of your home.  First floor internal spaces away from windows and exterior doors, such as closets, bathrooms, or areas under a stairwell.  Get into the kneeling position  Cover the back of the head and neck.

If your in a bathroom, get into the tub and assume the same position.  If possible drag a mattress to cover yourself.

When caught in other buildings, get to the first floor and look for the nearest bathroom or go to basement.  Sometimes, safe areas are marked.  Stay away     from windows and external doors.

When you see those environmental warning signals and a funnel cloud, leave your car immediately and drop into a ditch away from traffic, if possible.  Don't try to outrun a tornado in a car.

A mobile home even when tied down should be abandoned for a close-by sturdy structure or a ditch.

Graphics and information in italics is quoted from the National Weather Service web site at www.nssl.noaa.gov/NWSTornado/   For more details on tornadoes please visit this site.

 

Other emergency preparedness information links

 

York County's Office of Emergency Management

 

LIGHTNING SAFETY

 

Virginia Department of Emergency Management 

 

Federal Emergency Management Agency

 

 

F &LS Home