Featured Research

from universities, journals, and other organizations

Summer Thunderstorms May Become More Predictable

Date:
June 27, 2002
Source:
National Center For Atmospheric Research (NCAR)
Summary:
Meteorologists have long known that summer thunderstorms and heavy rains are difficult to predict. They pop up quickly and disappear within a few short hours. But after looking at large numbers of radar images over four years, scientists at the National Center for Atmospheric Research (NCAR) have discovered a systematic pattern of rainfall across the continent, day after day. That knowledge should make the rainiest summer thunderstorms more predictable.

BOULDER -- Meteorologists have long known that summer thunderstorms and heavy rains are difficult to predict. They pop up quickly and disappear within a few short hours. But after looking at large numbers of radar images over four years, scientists at the National Center for Atmospheric Research (NCAR) have discovered a systematic pattern of rainfall across the continent, day after day. That knowledge should make the rainiest summer thunderstorms more predictable.

The analysis of 50,000 summertime radar images showed that the movement of blocks of enhanced rainfall from west to east, from the Rockies toward the Appalachians, is an identifiable pattern, even when traditional weather maps show none of the typical weather patterns, such as fronts or low pressure systems.

These eastward-moving blocks of enhanced thunderstorm activity still have individual storms popping up quickly and disappearing in a few hours, but it appears that the older storms give birth to new storms as the activity moves across the country. Thus, there is a much greater chance that a particular location will feel the effects of a thunderstorm when one of the activity areas is passing by, rather than either before or after it.

"Heavy rain from thunderstorms is hard to predict because these storms are mostly local, don't last very long, and exhibit chaotic behavior in their evolution," said Richard Carbone, lead author of a paper appearing in the July 1 issue of the American Meteorological Society's Journal of Atmospheric Science. "But our work shows some clusters of storms actually spawn new clusters of storms. If we can follow this pattern, we may be able to greatly improve our predictions of where the new storms will develop."

A senior scientist at NCAR, Carbone and his colleagues applied sophisticated computer processing techniques to vast quantities of data containing radar imagery of summer thunderstorms between 1997 and 2000. By compiling the images they found a distinct pattern of old storms generating new storms downstream.

"We can track the signal associated with afternoon thunderstorms in the west to new thunderstorms across the country more than 500 miles on a typical midsummer day" added Carbone. "Some of these storms or 'episodes' last up to two days and 1,500 miles, even though ordinary thunderstorms last about an hour and organized groups of thunderstorms three to ten hours. You could say, for example, that yesterday's storms in Colorado have a lot to do with the likelihood of storms in Chicago today--and watch out on the East Coast tomorrow!"

Mountains and storm-created "waviness" in the atmosphere are mostly responsible for starting weather systems on their way across the country. But what links some of the thunderstorms together is still a mystery, said Carbone.

"We haven't discovered the 'silver bullet' yet--what ties these sequences of storms together--but we've got some ideas," said Carbone. Ongoing research by Carbone and his collaborators includes looking more deeply into how these episodes of enhanced thunderstorm activity form and what controls the speed at which they propagate across the central United States. If the underlying mechanisms can be brought to light, that information can be used to improve forecasts of thunderstorm activity in the summer months.

Carbone's thunderstorm research was funded primarily by the U.S. Weather Research Program.

NCAR (http://www.ncar.ucar.edu) is a national research laboratory managed by a consortium of 66 universities offering Ph.D.s in the atmospheric and related sciences. NCAR's primary sponsor is the National Science Foundation. The AMS (http://www.ametsoc.org/ams) is the nation's leading professional society for scientists in the atmospheric and related sciences.


Story Source:

The above story is based on materials provided by National Center For Atmospheric Research (NCAR). Note: Materials may be edited for content and length.


Cite This Page:

National Center For Atmospheric Research (NCAR). "Summer Thunderstorms May Become More Predictable." ScienceDaily. ScienceDaily, 27 June 2002. <www.sciencedaily.com/releases/2002/06/020627002855.htm>.
National Center For Atmospheric Research (NCAR). (2002, June 27). Summer Thunderstorms May Become More Predictable. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2002/06/020627002855.htm
National Center For Atmospheric Research (NCAR). "Summer Thunderstorms May Become More Predictable." ScienceDaily. www.sciencedaily.com/releases/2002/06/020627002855.htm (accessed September 17, 2014).

Share This



More Earth & Climate News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Researchers Explore Shipwrecks Off Calif. Coast

Researchers Explore Shipwrecks Off Calif. Coast

AP (Sep. 16, 2014) Federal researchers are exploring more than a dozen underwater sites where they believe ships sank in the treacherous waters west of San Francisco in the decades following the Gold Rush. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Isolated N. Korea Asks For International Help With Volcano

Isolated N. Korea Asks For International Help With Volcano

Newsy (Sep. 16, 2014) Mount Paektu volcano in North Korea is showing signs of life and there's not much known about it. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins