Region bracing for busy peak storm season

(CNS): Colorado State University hurricane researchers are still predicting a very active Atlantic hurricane season with a total of 23 named storms, down from 25 in their initial forecast. Four have already passed, which means we may see another 19 over the next three or four months. As TS Debby continued to deluge the southeast coast of the US, the experts are warning that another ten or more of those storms could reach hurricane strength, with at least four expected to become Category 3 or greater.

In a press release about the updated August forecast, the CSU storm experts said they had taken newly-available data into consideration as the peak of the season approaches. While there is uncertainty with all seasonal outlooks, the forecast team has higher confidence than normal that this season will be extremely busy.

They cited very warm sea surface temperatures in the tropical Atlantic as the primary factor pointing to an above-average season because warm ocean water serves as a fuel source. A warm Atlantic also leads to lower atmospheric pressure and a more unstable atmosphere. Both conditions favour hurricanes.

In addition, observed vertical wind shear during June and July was well below normal. Lower-than-normal shear during the early part of the hurricane season typically correlates with continued below-average shear during the peak of the season from August to October.

The experts explained that the potential transition to La Niña conditions in the next several weeks will weaken upper-level westerly winds across the Caribbean and the tropical Atlantic, favouring not just formation but intensification. Even if La Niña conditions are not met, the CSU team anticipates cool ENSO neutral conditions, which, when combined with the very warm Atlantic, would likely spell a well above-normal season.