Archive for May, 2013

Smith’s Event Risk Grading Alert For 2013 Atlantic Hurricane Season

May 24, 2013

NOAA Predicts Extremely Active 2013 Atlantic Hurricane Season
Smith’s Research & Gradings – May 23, 2013: In its 2013 Atlantic hurricane season outlook issued today, NOAA’s Climate Prediction Center is forecasting an active or extremely active season this year.

For the six-month hurricane season, which begins June 1, NOAA’s Atlantic Hurricane Season Outlook says there is a 70 percent likelihood of 13 to 20 named storms (winds of 39 mph or higher), of which 7 to 11 could become hurricanes (winds of 74 mph or higher), including 3 to 6 major hurricanes (Category 3, 4 or 5; winds of 111 mph or higher).

These ranges are well above the seasonal average of 12 named storms, 6 hurricanes and 3 major hurricanes. This era of high storm activity began in 1995 and the cycles historically last 25-40 years. Meaning, this era could last until 2020 – 2035.

The message from Kathryn Sullivan, Ph.D. and NOAA’s acting administrator and from Joseph Nimmich, associate administrator for response and recovery at FEMA was “Preparedness.” Dr. Sullivan said, “The emphasis of the news is not about percentages and ranges. The important news is about preparedness. Make your plans. Now is the time to pay attention to preparedness.”

Three climate factors that strongly control Atlantic hurricane activity are expected to come together to produce an active or extremely active 2013 hurricane season. These are:

• A continuation of the atmospheric climate pattern, which includes a strong west African monsoon, that is responsible for the ongoing era of high activity for Atlantic hurricanes that began in 1995;

• Warmer-than-average water temperatures (8/10°F above average) in the tropical Atlantic Ocean and Caribbean Sea; and

• El Niño is not expected to develop and suppress hurricane formation.

Dr. Gerry Bell, Ph.D., lead hurricane season forecaster at NOAA’s Climate Prediction Center noted, “There are no mitigating factors that would suppress the 2013 hurricane activity. El Niño mitigates hurricane activity, but it will not be a factor this year.

Improvements to NOAA’s forecasting were critical to limiting the loss of life in Moore, Oklahoma, where residents were given a 15-minute warning time before the EF5 tornado struck. Dr. Sullivan noted that in 1990, the average warning time for a tornado was 5 minutes.

Dr. Louis Uccellini, director of NOAA’s National Weather Service announced a series of new super computer upgrades will be coming online in July/August, providing more detailed models and better forecasting. These upgrades are in addition to Doppler radar data which this year will be transmitted in real time from NOAA’s hurricane hunters – the planes that fly across the U.S. and around the world, providing airborne platforms essential to the gathering environmental and geographic data for scientific research.

Dr. Sullivan said with these improvements – forecast models, data gathering, communications about post-tropical cyclone activity, transmission of real time data from airplanes, and procedure improvements could further improve the Hurricane Weather Research and Forecasting (HWRF) model forecasts by 10 to 15 percent. The primary area of improvement will be to NOAA’s storm Intensity forecast. The inclusion of wind fields and the vertical distribution of winds will be predicted with more accuracy.

Other improvements such as storm surge mapping will be ready to operational next season.

While NOAA’s Atlantic hurricane season outlook provides the probability of severe events along the Atlantic and Gulf Coasts, the agency is not able to provide an outlook for specific areas. Dr. Sullivan said, “Weather risk exposure is high – extremely high. We cannot give you a specific location. This is your warning.”

There has not been a major landfall hurricane since 2005, and NOAA cannot predict when the next one will happen. Dr. Bell explained that there is a set of conditions that allow storms to form, and another that allow them to make landfall. An upper level trough has kept many storms out at sea. In 2003-2005, high pressure over the east, tended to keep storms further west. The pattern is linked to the jet stream.

In light of budget cuts and sequestration, NOAA has a plan in to Congress to decrease budget impacts, while still providing Americans the data coverage to keep them informed.

Contact: Pam Kilbourn
(571) 299-4954
pamkilbourn@smithsresearch.net

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