In Texas, June 1 marks the beginning of hurricane season, and this means residents along the Gulf Coast want to know what to expect from any storms that come barreling out of the Atlantic and Caribbean basins.
The 2016 hurricane season is certainly expected to be more lively than last year. It got off to an early start on January 6 when the first storm, Hurricane Alex, formed off the northern Cuba and wandered eastwards, hit the Azores Islands out by Portugal, and fell apart in the North Atlantic a week later. And most recently, sudden but short-lived Tropical Storm Bonnie drenched the Carolinas.
This year’s roundup of hurricane predictions from four different weather and climate institutions. Each of them makes clear the increased threat of severe storms compared to the last two years, but they also highlight the uncertainty in what the season holds, especially between August and October, considered the peak of any hurricane season.
Good Bye El Niño, and Hello La Niña!
Forecasters this year are split between calling 2016 a near-normal to average season or an active to moderately active season. The National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center, Colorado State University (CSU), the Weather Company (formerly Weather Services International), and Tropical Storm Risk (TSR), Department of Space and Climate Physics, University College London, all point to three specific factors that will enhance hurricane formation. However, they all indicate some degree on uncertainty in their predictions because these same factors are processes that will change over time.
1) How and When El Niño will Weaken
In general, an El Niño produces east-ward blowing wind shears off the Leeward Islands in the Caribbean Sea that stretch out to the hurricane Main Development Region (MDR) — just off the west African coast. Hurricanes prefer to form over warm water in quiet, calmly rising air so they can then grow into strong convection systems. However, wind shearing from an El Niño disrupts those air currents and makes it harder for storms to form. On the flip side, a La Niñas tends to have very little wind shearing, but forecasters can’t determine how fast the El Niño transitions to a La Niña and it’s not clear how strong it might be.
2) Sea Surface Temperatures (SST)
While warm water is in place off the coast of the eastern United States, colder water in the north Atlantic and off the coast of west Africa adjacent to the MDR could reduce chances for storm formation because cold water can’t provide very much heat energy to a hurricane. On the other hand, these temperatures could warm sharply as the summer wears on, but it’s difficult to predict this with any real accuracy.
3) The Atlantic Multi-decadal Oscillation (AMO).
The AMO is a climate pattern that lasts about 25 to 40 years, and it’s marked by SSTs in the north Atlantic and the MDR that are both warmer or cooler. During warmer SST periods, there is above-normal hurricane activity, but during cooler SST periods, the hurricane activity is generally below-normal . The question currently is whether the high-activity period that began in 1995 is ending, has ended, or is still going.
Breaking Down the Predictions and Forecasters
1) NOAA’s Climate Prediction Center
This prediction calls for a 45% chance of a near-normal season — but it also includes a 30% chance of an above-normal season and a 25% chance of a below-normal season. The outlook is complicated by ALL the uncertainty they see (which we mentioned earlier):
- The rate the current El Niño fades into a La Niña and the relative strength of both.
- The status of the AMO. Has a cooling phase begun or are we still in a warm AMO phase?
- Fluctuations in Atlantic SSTs. It is unclear if the observed SST changes over the past three years are indicate changes in the AMO or if they reflect short-term variables. Surface temperatures in the north Atlantic and in the MDR from January to April were cooler than average. However, last year’s SST in the MDR warmed as summer progressed to becoming the 5th highest on record — which is not consistent with a cooling phase.
Here is a forecast for an average season, but it’s based on that La Niña emerging in September. The CSU also believes the AMO has entered a cold phase and that cold water in the North Atlantic might interact with strong Atlantic high pressure circulations to drive ocean currents carrying cold water southward to the MDR.
3) The Weather Company
This forecast for an active season during the busy August to October months is based upon a belief that the cold waters will warm in the MDR and that the expected La Niña as predicted. They also foresee the United States experiencing its hottest summer since 2012, especially in northern states.
Forecasting a moderately active hurricane season, there is an expectation for warmer SSTs in the MDR during August and September, combined with fading winds shearing due to the emergence of that La Niña. How fast the La Niña emerges and how strong it might be serve as the biggest reasons for uncertainty with this prediction.
The CSU and NOAA’s National Hurricane Center will provide updates later in June, and the NOAA will also issue a further update in early August. If these predictions change substantially, we’ll update you at that time.
Texas has already endured a soggy and dangerous spring with continued rainstorms. The threat of an active hurricane season further escalates the threat of inland flooding in the event a storm system sets a course for Texas. Be watchful and get prepared!
Get ready for any storm that might visit Texas by heading over to the Light Lab’s Weather Prep Center for tips on how to prepare for the big storms, what to do when the lights go out, and more. You can also keep informed about storm-related emergencies and news by following First Choice Power on Twitter and our Facebook page.