NOAA, the federal agency in charge of the National Weather Service, and forecasters at Colorado State University issued their final hurricane season forecasts this morning heading into the busiest stretch of the Atlantic hurricane season.
The updated forecasts continue to predict an active Atlantic hurricane season, with up to 20 named storms, eight hurricanes, and five Category 3 or stronger hurricanes.
The 30-year average is 14 named storms, seven hurricanes and three Category 3 or stronger hurricanes. So far, three named storms but no hurricanes have formed in the Atlantic, suggesting a very active few months still to go.
The updates to these hurricane season forecasts are lower than forecasts issued earlier this year but remain historically high and in line with August forecasts issued ahead of the busy 2021 Atlantic hurricane season. Hurricane season forecasts issued in August come just before the traditional ramp up in hurricane activity and generally show good skill.
The slight reduction in seasonal forecast numbers is largely due to tepid tropical Atlantic waters this July and a cooling of Atlantic waters north of the main tropical development region.
A cooling of this subtropical region often enhances the presence of disruptive systems from outside the tropics that can both increase hostile wind shear and inject dry air into the typically water-laden tropical atmosphere. While tropical Atlantic waters have cooled some in recent weeks, forecasters note the reduction in easterly trade winds expected this month should allow the Atlantic to warm again by late August.
Colorado State University was the first group to issue hurricane season forecasts beginning in 1984. The U.S. government began issuing regular hurricane season outlooks in 1998.
Seasonal hurricane forecasts cannot predict when or where a storm may strike. Some active hurricane seasons like 2010, which recorded 12 hurricanes, finish with few or no hurricane landfalls, while other typical seasons like 1985, which recorded seven hurricanes but six U.S. landfalls, see lots of hurricane strikes.
Even “down” seasons like 1992, which recorded significantly below average activity, can produce catastrophic storms like Hurricane Andrew.
Regardless of seasonal hurricane forecasts, it only takes one storm to make a bad hurricane season.
This week the tropics remain quiet, but have your hurricane plan and supplies ready, especially as we confront the busiest part of the Atlantic hurricane season.