Project Stormfury - the ESSA/Navy hurricane research and modification program - will attempt to seed hurricanes massively and repeatedly, to learn whether the force of these storms can be diminished. The Project’s major goal this season is to repeat the eyewall-seeding experiments conducted in 1969, in the hope of confirming the results. Other experiments planned for the 1970 season include seeding of hurricane rain bands and rain sectors, and continuation of experiments on lines of tropical cumulus clouds not associated with hurricanes.
Project Stormfury’s 1970 season will open July 23 after a “dry-run” rehearsal by participating aircraft from the Research Flight Facility, the Navy, and the Air Force. Thereafter, Stormfury scientists, planes, and flight crews will be on 48-hour alert for hurricane seeding through October 31.
Experiments will be conducted on storms in the south-western Atlantic, the Caribbean, and t he Gulf of Mexico, when the probability is small - 10 percent or less - that the hurricane center will come within 50 miles of a populated area during the ensuing 24 hours. The 24-hour period gives Project aircraft ample time to measure the effects of seeding before they are obscured by the proximity to land.
In 1969, on August 18 and again on August 20, Hurricane Debbie was seeded five times during an eight-hour period. These were the first such experiments conducted since 1961 and 1963, and the first ever to seed a storm more than once per day. 
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