As we head into August, we are nearing the middle of the Atlantic hurricane season.
The official start is June 1 and ends November 30 although tropical systems can develop at just about any time of the year.
The National Oceanic and Atmospheric Administration’s Climate Prediction Center is forecasting a near-normal Atlantic hurricane season is most likely in 2019. An average hurricane season produces 12 named storms, of which six become hurricanes, including three major ones.
For 2019, NOAA is predicting nine to 15 named storms (winds of 63 kilometres per hour or higher).
Four to eight could become hurricanes (winds of 119 km/h or higher), including two to four major hurricanes (category 3, 4 or 5; with winds of 179 km/h or higher).
NOAA provides these ranges with 70 percent confidence. So far this year two named storms have developed in the Atlantic.
This outlook reflects competing climate factors.
Over the past few months, El Nino conditions have developed in the Pacific Ocean, meaning sea-surface temperatures in the eastern tropics are warmer than normal.
In general, El Nino conditions tend to suppress Atlantic hurricane formation, as a result of increases in upper-level winds that tear apart developing storms.
Countering El Nino is the expected combination of warmer-than-average sea surface temperatures in the tropical Atlantic Ocean and Caribbean Sea, and an enhanced west African monsoon, both of which favour increased hurricane activity.
This year, NOAA’s National Weather Service (NWS) is upgrading its Global Forecast System. This marks the first major upgrade in almost 40 years and will improve tropical cyclone track and intensity forecasts.
“NOAA is driving towards a community-based development programme for future weather and climate modelling to deliver the very best forecasts,” said Neil Jacobs, acting NOAA administrator.
Also this year, NOAA’s fleet of Earth-observing satellites includes three new operational next-generation satellites. The unique, valuable data from these satellites is fed into the hurricane forecast models to help forecasters make critical decisions days in advance, and to prepare communities that may be affected by impending storms.
For the 2019 season, NOAA’s Hurricane Hunter aircraft will collect higher-resolution data from upgraded onboard radar systems. These enhanced observations will be transmitted in near-real time to hurricane specialists at the National Hurricane Center, the Central Pacific Hurricane Center, and forecasters at NWS Weather Forecast Offices.
As the Atlantic hurricane season progresses, NOAA’s Climate Prediction Center will publish an update to the 2019 Atlantic seasonal outlook next month, just before the historical peak of the season.
Despite 2019 being forecast as an “average season”, hurricane preparedness remains critical, just as it is every year.