NWS Little Rock, AR - Text Viewer

ZCZC LITWRKPNS
TTAA00 KLIT 041200
ARZ003>008-012>017-021>025-030>034-037>047-052>057-062>069-042000-

Public Information Statement
National Weather Service Little Rock AR
600 AM CST Thu Mar 04 2021

...Todays Topic for Severe Weather Awareness Week is 
Severe Thunderstorms...

The National Weather Service, in cooperation with the Arkansas 
Department of Emergency Management, has proclaimed the week of 
February 28th through March 6th as Severe Weather Awareness Week 
in Arkansas.  

A different topic will be discussed each day, and todays topic is 
Severe Thunderstorms. 

At any given moment around the world, approximately 1800 
thunderstorms are occurring. Although thunderstorms are relatively 
small, when considered on a global scale of weather, all 
thunderstorms are dangerous. Lightning, flash floods, hail, 
straight-line winds, and tornadoes all result from thunderstorms. 

A thunderstorm is considered severe when it produces winds of at 
least 58 mph, hail at least 1 inch in diameter /the size of a 
quarter/, and/or a tornado. 

Hail forms in storm clouds where the air is subfreezing. Updrafts 
which feed storm clouds drive raindrops skyward, and liquid turns 
to ice. Quite often, hailstones will fall through the cloud, 
collect water, and updrafts will force them aloft. The stones 
refreeze and get larger. 

In 2020, there was huge hail on May 4th. Storms unleashed baseball 
to softball size hailstones at Fayetteville /Washington County/, 
Rogers /Benton County/, and Shady Grove /Washington County/! This 
broke windshields, and dented vehicles and metal roofs. Just 
southeast of Johnson /Washington County/, a five inch diameter 
hailstone was observed. This tied the state record for the largest 
hail on January 21st of 1999 and April 2nd of 2006.

Large hail, on average, causes over one billion dollars in damage 
/property and crops/ in the United States each year. Some injuries 
due to large hail occur in this country each year, but deaths from 
hail are relatively rare. Animals fare far worse than humans. 

When updrafts are overcome by rain and hail in storms, air from 
aloft can descend in a hurry. When these downdrafts hit the ground 
and spread out in all directions, damaging straight-line wind gusts 
sometimes result. 

In 2020, a bowing line of fast moving thunderstorms cut through 
central and southern Arkansas during the late afternoon and evening
of April 12th. There were widespread wind gusts of 60 to more than
80 mph. Numerous trees and power lines were downed, and there was
some structural damage. Power was knocked out to at least 
150,000 homes. Altogether, there were roughly three dozen 
instances of gusts of at least 75 mph during the year. 

Occasionally, thunderstorms spawn tornadoes. Most of these are 
produced in the spring and fall during the afternoon and evening. 
There are 33 tornadoes in a typical year. There were 45 tornadoes 
locally in 2020, and these resulted in no fatalities. 

Two other hazards associated with thunderstorms are lightning and 
flash floods. However, these are not considered severe. 

Whenever thunder is heard, there is lightning nearby. Lightning is 
deadly, especially in the summer when people are outdoors. 

Flash floods are another thunderstorm hazard. Vehicles driven into 
flooded areas result in the greatest number of flash flood deaths. 

Across the country, the top three deadliest thunderstorm hazards 
in the last 30 years years were flash floods, tornadoes, and 
lightning /in that order/. 

...Some Severe Weather Safety Rules...

Know the difference between a watch and a warning. The National 
Weather Service issues watches when conditions are favorable for 
the development of severe weather. Warnings are reserved for cases 
where severe weather is imminent or occurring. 

If a Severe Thunderstorm Warning or Tornado Warning is issued 
for your area, do not hesitate to find a place of safety. If a 
safe room is not available, the next best location is the lowest 
floor of a permanant structure in an interior room away from 
windows. Put as many walls between you and the outdoors as you 
can. 

Make sure that you have a source to receive the latest 
information, such as NOAA Weather Radio All Hazards, commercial 
radio, TV stations or cable TV. Other sources of warning 
information can include telephone notification services to 
which people subscribe, pagers and cell phones. 

&&

For a list of all the tornadoes and other significant weather 
events that occurred in 2020...

https://www.weather.gov/media/lzk/StormsOf2020.pdf

$$

46