Hurricane Good News Bad News

First the bad news. Taiwan is going to get slammed with Typhoon Soudelor over the next day (landfall at about 8:00 AM local time). Soudelor was one of the strongest typhoons earlier during its development but weakened to a Category 1. However, very warm seas, lack of wind shear, and other factors may make Doudelor return to category 3 or even 4 strength before making landfall. Also, it is large.

The storm is likely to hit Taiwan in about the middle, which along the east coast is not heavily populated. But it will bring heavy rains, likely causing landslides and floods, to the mountainous middle of the island. On the other hand, the storm is moving quickly, so if it moves onto land and then moves through quickly, the total rain accumulation may be attenuated. After crossing Taiwan, the storm will hit mainland China.

Bob Henson at Weather Underground has a summary, but it is from yesterday.

Now the good news. NOAA has revised the estimate for the overall strength of the so far anemic Atlantic hurricane season, downgrading it a bit.

The NOAA Climate Prediction Center’s updated 2015 Atlantic Hurricane Season Outlook calls for a 90 percent chance of a below-normal hurricane season. A below-normal season is now even more likely than predicted in May, when the likelihood of a below-normal season was 70 percent.

This is largely due to increased vertical wind shear as a result of the strong El Niño we are experiencing. The agency is predicting between 6 and 10 named storms, with only 1-4 of them being hurricanes, with between zero and one being major hurricanes. So far the Atlantic has had three named storms, one of which managed to be hurricanes. A typical (average) season would have about 3 or 4 named storms (so this seems on track to be average) but by n ow on average one of the would be likely to be a hurricane. The El Niño related factors likely to attenuate a storm season are increasing and likely to maintain or increase over coming months.