As I write this, more than 100 researchers from the United States, Italy, United Kingdom, Netherlands, Germany, Canada, and Australia, with a fleet of more than fifty Doppler radar equipped mobile laboratories are swarming the Great Plains in search of thunderstorms and tornadoes to try and give the world a better understanding about severe weather. These researchers in question, are drawn from more than a dozen universities, and several private and governmental organizations, with the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration taking the lead role in funding the whole project, which is known as the Verification of the Origins of Rotation in Tornadoes Experiment 2, or VORTEX2.
VORTEX2 is the sequel to the original VORTEX, which began in the 90’s and served as the inspiration to the film Twister. Due to the success of the original project, VORTEX2 is greatly expanded, and is the most ambitious tornado research project ever assembled. The project seeks to understand better how tornados form, how long they last, and what causes them to dissipate. To do this of course, requires throwing radar-equipped vehicles right into harms way, in the peak of tornado season, in the most tornado-heavy part of the United States. So from May 1 to June 15, crews will be swarming the Midwest in search of twisters. So far, they’ve found plenty.
I was lucky enough to catch up with Steven Cobb, the National Weather Service liaison to VORTEX2. Steven answered all my questions about the project, and I present them here to share with you:
Me: With all the information you gain about tornadoes and dangerous weather events, how would NWS and other organizations use this in their everyday work?
SC: The primary focus of the Vortex2 (V2) project is to better understand how and why tornadoes form and why certain thunderstorms produce tornadoes while other do not. The V2 teams are studying a certain variety of thunderstorms called Supercells, which are characterized by a rotating updraft that produces the majority of tornadoes. Better understanding of the parent thunderstorm and the environments they form in will also help us to better model and predict these extreme events. The NWS can then utilize this information to improve warning decisions and to increase the lead-time or notice to the public before a tornado develops.
For us in the NWS to improve our near term forecasts we also must improve the forecast models and the V2 project will help in that respect by taking detailed observations from near the ground to cloud base. These observations then can help us determine which weather parameters are most important in tornado formation and how we can better predict them. Another important technology is weather radar and a more complete understanding of tornadoes and the storms that produce them will also aid in designing future radar systems. Already an update is planned for the network of weather radars operated by the NWS, which will help refine estimates in precipitation rate and detection of large hail. Similarly, observations during VORTEX2 will help determine the best strategies for scanning thunderstorms.
Me: I read on the VORTEX2 site that the NWS claims a 70% false positive for tornado detection? Where does that number come from and how will VORTEX2 improve that number?
SC: The local NWS office may issue a tornado warning based solely on weather radar signatures commonly associated with storms that produce tornadoes or by actual reports of a funnel cloud by storm spotters. Occasionally the tornado warning is issued following a tornado report. If no tornado is observed during the valid time of a warning then that is considered a false alarm. There are many thunderstorms that have the potential to produce tornadoes and some even produce funnel clouds that descend from the base of the thunderstorm but the circulation never reaches the ground to form a tornado. In cases such as the latter two, a tornado warning would be considered a false alarm since no visible tornado or circulation (visible by dust or debris) reached the ground.
Me: Is it possible that amateur weather stations connected to the Internet could someday add to the better prediction of tornados? Is there any plan to use distributed computing in a manner similar to Stanford's Quake Catcher Network?
SC: There are currently plans to expand the existing network of official weather observations collected by the NWS but that is primarily by modernizing the existing 11,000 cooperative observer or volunteer weather stations. All of these stations are specially situated to provide the best measurements of near-ground conditions while not being influenced by unnatural sources such as buildings or other man-made objects. Many NWS offices also utilize the existing meso-networks operated by Universities and various state agencies across the United States as well as observing networks sponsored by local media outlets (frequently referred to as schoolnets). No matter what the source, a very thorough quality control is performed before the data is used as input in our computer model forecasts.
NWS forecasters have access to over a dozen computer models forecasts at different time and spatial resolutions including some forecast systems which in themselves may have dozens of individual computer model inputs. The goal of these computer forecasts is to give the forecaster the best possible idea about the environment in which thunderstorms may form. Again, the aim of VORTEX2 is to help us better understand the environment that tornadoes form in and improve the computer models we use to predict thunderstorm development. In the end we hope to better distinguish areas and times most favorable for supercell thunderstorms and eventual tornadoes.
We ask that you at home leave the tornado chasing to scientists, and if you haven’t already, we ask that you familiarize yourself with Dealing With A Tornado.
For those of you who want to get close to a tornado, we recommend visiting the VORTEX2 official site, or watching the Weather Channel’s “The Great Weather Hunt.” The Weather Channel crew is traveling with VORTEX2 researchers and has so far aired some amazing footage of tornadoes and thunderstorms. You can find more about the show at the Weather Channel’s mini-portal for the Great Weather Hunt.