This past week, hurricane forecasters at Colorado State University released their preliminary forecast for the number of tropical storms and hurricanes expected to form in the Atlantic basin this season. They predict a total of 13 tropical storms will form, of which six will become hurricanes. A tropical storm becomes a hurricane when its sustained winds reach 74 mph. A typical year averages about 14 tropical storms, with seven spinning into hurricanes, based on weather records that date from 1991 to 2020. The forecasters relate the lower numbers to the growing El Nino, which can cause a strong jet stream aloft that disrupts the development of storms. However, they also point out that warmer than average ocean temperatures could provide extra fuel to tropical waves, so there is more uncertainty than usual.
For a refresher on the “cone of uncertainty” used by the National Hurricane Center in their forecasts and some updated information on the cone size, check out this blog post from tropical specialist Brian McNoldy.
