BIRMINGHAM, Ala. (WBRC) - Colorado State University predicts a more active than usual 2021 Atlantic hurricane season. They predict 17 named storms, eight hurricanes, and four major hurricanes, meaning winds 115 mph or greater or Category 3 or higher. The forecast is above the 30-year average of 15 named storms, seven hurricanes, and three major hurricanes.
Hurricane season officially runs from June through November, but storms can occasionally develop outside of those months. They anticipate an above-average chance for major hurricanes making landfall along the U.S. coastline and in the Caribbean, but folks need to remember that all it takes is one hurricane making landfall to make it an active season for them. The prediction shouldn’t change how folks prepare each year. Each season can deliver many storms but have little impact, or deliver a few storms, and have a couple hit land with major impacts. It’s impossible to know for certain if a hurricane will hit land this season, but we need to prepare for that potential.
Remember, weak tropical storms can cause major issues, too, like flooding. El Niño/La Niña, the periodic warming/cooling of the equatorial eastern and central Pacific Ocean, can shift weather patterns over a period of months. Its status is always one factor considered in hurricane season forecasting. As of early spring, a La Niña was fading and a transition to neutral conditions is likely by the time hurricane season begins. Lack of El Niño will means less shear to rip apart tropical systems that try and form. The experts don’t expect that to be a suppressing factor in play this season. La Niña has the opposite effect, leading to less wind shear, rising motion and, often, very active seasons. Hurricane seasons can be active even if La Niña is absent, too. Water temperature is examined closely by meteorologists, which is the other factor considered when making a hurricane forecast.
Waters are already above normal and that will likely be the case going forward. An above-average number of tropical systems are more likely if temperatures in their main development region are warmer than average and there is little wind shear. Saharan Dust will need to be monitored to see if it might become a limiting factor, but it’s too early to know that.