NOAA predicts higher than average number of tropical systems in 2020
With a little more than one week before the official start of hurricane season and days after the first named storm of the year, tropical experts with the National Hurricane Center are predicting above average activity this hurricane season. Their forecast calls for: 13-19 named storms, 6-10 hurricanes and 3-6 major hurricanes (category 3 strength or higher). The outlook predicts a 60% chance of an above-normal season, a 30% chance of a near-normal season and only a 10% chance of a below-normal season. NOAA provides these numbers with 70% confidence. NOAA will re-visit and update their seasonal outlook in August, as we enter the peak months of hurricane season. Annual averages are 12 named storms, 6 hurricanes and 3 major hurricanes. Earlier this year, another reputable research outfit at Colorado State University predicted 16 named storms and 8 hurricanes with 4 being considered major.
The team cited an absence of El Niño the potential for weak La Niña conditions by the middle of summer. Additionally, sea surface temperatures across the Atlantic Basin are slightly above average and are forecast to remain that way.
La Niña is a pattern, which favors much more activity in the Atlantic Basin during hurricane season. During La Niña, trade winds weaken over the Atlantic Ocean creating a supportive environment for tropical cyclone formation.
Warm sea surface temperatures enhance evaporation and cloud development. In the presence of favorable winds, heat energy from the oceans promotes tropical cyclone strengthening.
As defined by the National Oceanic and Atmospheric Administration (NOAA), El Niño and La Niña are the warm and cool phases of a recurring climate pattern across the tropical Pacific—the El Niño-Southern Oscillation, or “ENSO” for short. Keep in mind that El Niño and La Niña do not “cause” any one specific weather event; rather the two phases of ENSO influence change in global climate patterns that then increase the likelihood of specific weather events. Once again, ENSO is not “to blame” for any one storm system, temperature anomaly or hurricane. If La Niña does indeed develop, the Atlantic Basin faces an increased chance at above average tropical activity. Despite higher chances, it is much too early to determine where storms will develop or where they will go.
The National Hurricane Center and the WBRZ Weather Team remind that “it only takes one hurricane making landfall to make it an active season for you,” so prepare accordingly. For more on the season ahead and preparedness, visit wbrz.com/weather and click on the hurricane center.