Project TWISTEX 2007

TWISTEX or Tactical Weather Instrumented Sampling in/near Tornadoes EXperiment is a collaboration between Tim Samaras, WindLogics (Bruce Lee and Cathy Finley), Iowa State University, and each of their respective partners in funding. This project will be running full-time from roughly May 1 though June 30, a crew of approximately 7 people in 4 vehicles.

TWISTEX is a field research study to collect data that pertains to tornadoes, hail and lightning. Tornado data will be gathered by in-situ probes that are to be placed in the path of the tornado in hopes of the tornado traveling over them. These probes gather temperature, humidity, wind speed/direction and visualization at rates of 10 samples per second. Three of the vehicles are also equipped with mobile mesonets, which will be used for hopeful measurement of the RFD and combined with probe data for a complete thermodynamic mapping of near storm environment. Successful measurement of the RFD and near-storm environment along with in-situ data of a tornado simultaneously has never been done.
The project will also be collecting large hail (>2") and its' impact on selected targets, along with terminal velocity of these hailstones. One vehicle is 'hardened' to survive large hail impacts while this study is conducted.
Lightning is another part of this study, where extremely high speed cameras will be in use to measure specific durations that it takes for things such as the stepped leader/return stroke and its' attachment.

The project has nearly completed its' first month of activities, with the month of June and its' respective crew getting prepared. I was selected as one of the ISU students to be a part of this project and will be active for this entire month in all of the TWISTEX activities. As some may have noticed on previous posts, near the end of them have had a 'TWISTEX Update'. These updates will now become the main focus of the blog over the next month. Those still interested in the general forecast posts for Iowa, they will still be posted when I am not out in the field. Blog posts from now on will contain my current location, TWISTEX forecast, followed by any updates from previous days and its' activities. If it is an 'off' day, the general forecast for Iowa will likely follow that information.

I encourage you to continue reading my blog for information, posting comments is encouraged as well! When possible I will have nearly 'live' updates on the blog, along with updated radar views on my Iowa Chaser website. This is a very unique opportunity that I hope to share with you for your enjoyment as well... Thanks!

TWISTEX Update: Closed low over the northern plains is producing severe weather but tornadic threat is only marginal, thus no deployment is planned. The closed low will become swept up into the flow by the June 3/4, aiding in deamplifying the trough in the east. Northwest flow looks to remain over the plains states until mid-week next week when at least zonal flow will take over. Some models indicating a strong wave moving over the plains by next Wednesday/Thursday providing a severe weather risk for the plains. The GFS is flip flopping on this solution, ECMWF indicating strong trough in the west for late week next week keeping the severe threat going. The JMA model has northwest flow in tact as far as next Tuesday, but does show a wave coming onto the coast at that time as well (collaborating with other models). The GEM in the same boat as the JMA, with northwest flow shown on Tuesday, but strong wave on the coast by that time as well. Reason to believe the next strong risk for severe weather (w/ favorable tornadic parameters) will be mid to late week next week (June 5-9). Deployment for TWISTEX is probable for June 5th as of current forecasts, more details as event nears.