Featured Research

from universities, journals, and other organizations

Scientists To Probe Giant Storm Clusters Across Mid-Western States

Date:
May 6, 2003
Source:
National Science Foundation
Summary:
From the air and the ground, scientists this spring and summer will examine some of the world's largest thunderstorm complexes, behemoths that can spread hurricane-force wind and torrential rain for hundreds of miles across the U.S. Midwest.

Arlington, Va. -- From the air and the ground, scientists this spring and summer will examine some of the world's largest thunderstorm complexes, behemoths that can spread hurricane-force wind and torrential rain for hundreds of miles across the U.S. Midwest. The study, scheduled from May 20 to July 6, should provide the clearest picture to date of how such storms wreak havoc and how forecasters can better predict trails of storm damage.

The Bow Echo and MCV Experiment (BAMEX) is organized by scientists Christopher Davis and Morris Weisman at the National Center for Atmospheric Research (NCAR) in Boulder, Colo. MCV stands for mesoscale convective vortex, a low-pressure center associated with large clusters of storms. The $4 million study is funded primarily by the National Science Foundation (NSF). Collaborators include the National Oceanic and Atmospheric Administration (NOAA), the Naval Research Laboratory, and a dozen colleges and universities (listed below).

The BAMEX study area encompasses most of the Midwest. Field operations, including three aircraft and a forecast center, are based at MidAmerica Airport, just east of St. Louis. Mobile weather labs will traverse the study area. Ron Przybylinski of NOAA's National Weather Service (NWS) office in St. Louis says forecasters in the region are eager to participate in BAMEX, which is the area's biggest thunderstorm-related study since the 1970s. "This is a once-in-a-lifetime experience. The more knowledge we have about the evolution of these systems, the better we can predict them."

Unlike many summer storms that develop and decay in an hour or two, mesoscale convective systems—which can produce bow echoes and MCVs—are often large, intense and long lasting. Typically, such a system develops in the warmth of the late afternoon and can last through the night. As it grows, a downdraft of high winds from rain-cooled air can push it into a bow-like configuration, seen as a bow echo on radar. Weak tornadoes may form along the bow or at either end, but the main threat is from straight-line winds that can gust to over 100 miles per hour.

While a typical tornadic thunderstorm might span 12 miles, the long-lived systems studied in BAMEX can stretch more than 90 miles in width and carve paths more than 500 miles long. Such storms can be terrifying, especially late at night when they are most likely to occur across much of the Midwest. On the night of July 26, 1990, a bow echo barreled through Kansas City packing winds of 74 mph. The storm ripped off roofs, downed trees and cut electric power to about 100,000 homes and businesses.

Between January 1995 and July 2000, high winds from U.S. mesoscale convective systems caused over $1.4 billion in damage, 72 deaths and over 1,000 injuries. BAMEX will study how these damaging winds unfold at night, when low-level air usually cools and stabilizes.

After a mesoscale convective system dissipates, its vortex may persist as a focus for new storms the next day, making the vortex a potential forecasting tool. Several days of storms can be triggered as an MCV makes its way across the central and eastern United States. "This characteristic of an MCV is most interesting, as it implies a greater degree of predictability in storm initiation than previously thought possible," says Steve Nelson, program director for mesoscale meteorology at NSF. Heavy rain is a particular threat with these multi-day episodes. One July 1977 MCV that formed in South Dakota ended up producing a catastrophic flood in Johnstown, Pa., killing 78 people.

Although researchers have made progress simulating mesoscale convective systems with computer models, there have been no large-scale experiments in recent years aimed at gathering data on these enormous complexes. According to Weisman, "We came to realize that we'd gone about as far as we could with the idealized simulations. We needed to get good data."

During BAMEX, three research aircraft will track developing bow echoes and MCVs as they move east across the Midwest from South Dakota, Nebraska, and Kansas to the Ohio Valley. Two of the aircraft have Doppler radar on board. A third will release dropsondes—instrument packages that sample the atmosphere and transmit weather data as they gently descend via parachute.

Ground-based crews will intercept the storms in mobile weather laboratories, deploying weather balloons and using atmospheric profilers and other instruments to sample the storm environment. "It's going to be unique in that we'll be all over the place and never know where we'll be the next night," says NCAR's Ned Chamberlain, who is overseeing the balloon launches. "We'll be driving hundreds of miles in a day." To capture the nighttime phase of the mesoscale systems, each day's activity could extend from four o’clock in the afternoon to two o’clock in the morning.

Forecasters from NWS offices throughout the Midwest will take turns sharing their expertise in St. Louis, examining computer models and diagnosing storm behavior. The data gleaned from BAMEX should enable forecasters to improve their warnings for the high winds produced by bow echoes and the heavy rains triggered by MCVs. The Joint Office for Science Support (JOSS)—part of the University Corporation for Atmospheric Research, which operates NCAR—has built a Web-based catalog to provide up-to-the-minute field data and serve as an archive for later use. JOSS is also teaming with NCAR and other participants to set up and staff the BAMEX operations center. The project will benefit greatly from the expertise of the NWS forecasters on hand, according to JOSS's James Moore. "We expect to take advantage of their local knowledge and appreciation for these strong mesoscale systems. They'll be a real asset," he said.


Story Source:

The above story is based on materials provided by National Science Foundation. Note: Materials may be edited for content and length.


Cite This Page:

National Science Foundation. "Scientists To Probe Giant Storm Clusters Across Mid-Western States." ScienceDaily. ScienceDaily, 6 May 2003. <www.sciencedaily.com/releases/2003/05/030506073152.htm>.
National Science Foundation. (2003, May 6). Scientists To Probe Giant Storm Clusters Across Mid-Western States. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2003/05/030506073152.htm
National Science Foundation. "Scientists To Probe Giant Storm Clusters Across Mid-Western States." ScienceDaily. www.sciencedaily.com/releases/2003/05/030506073152.htm (accessed July 29, 2014).

Share This




More Earth & Climate News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. 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