5104 Caroline Houston, Texas 77004 Phone: 713-529-3076 Fax: 713-528-3538 E-mail: wrc@wxresearch.org

 

Press Release

For Immediate Release

November 30, 2004

November 30th marks the end of the 2004 Atlantic Hurricane Season

Weather Research Center’s 2004 OCSI’s Atlantic Hurricane Season

Forecast Verifies

Houston – According to meteorologist Jill F. Hasling of Weather Research Center [WRC®], the 2004 Atlantic Hurricane Season will be remembered for many years to come. The coast with the highest risk of experiencing a land falling tropical storm or hurricane in the 2004 hurricane season was the west coast of Florida with a 70% chance based on the Orbital Cyclone Strike Index [OCSI]. This prediction verified with the landfall of Tropical Storm Bonnie on August 12th, Hurricane Charley on August 13th, and Hurricane Ivan on September 16th. Each day during the month of September there was an active storm somewhere in the Atlantic.

The table below gives the probability of landfall for a tropical storm or hurricane on different coast lines of the United States was forecast for the 2004 Atlantic Hurricane Season based on the OCSI, the probability based on climatology and the name of the storms which made landfall on the section of the coast line which experienced a storm.

2004 OCSI FORECAST FOR THE ATLANTIC

COAST OCSI CLIMATOLOGY 2004 LANDFALLS

Mexico 50% 40%

Texas 60% 51% Ivan

Louisiana to Alabama 40% 59% Ivan, Matthew West Florida 70% 71% Bonnie, Charley,

Frances and Ivan

East Florida 30% 41% Frances, Jeanne

Georgia to N. Carolina 40% 56% Alex, Gaston

East Coast of US 20% 36% Gaston

Gulf Oil Blocks 70% 88% Bonnie

The 2004 Atlantic Hurricane Season began slowly with the first tropical depression forming on the 31st of July. The slow start was no indication of what was in store for the remainder of the season. There were 14 named cyclones with 8 intensifying into hurricanes and 1 sub-tropical storm Nicole. Seven Category 3 or stronger hurricanes formed in Atlantic Basin this season: Alex, Charley, Danielle, Frances, Ivan, Jeanne, and Karl. Karl was the only major hurricane that did not make landfall along the United States coast. Nine storms made landfall along the United States with five of these storms [Bonnie, Charley, Frances, Jeanne and Ivan] making landfall in Florida. The last time at least 9 cyclones made landfall on the United States coast was 1916.

The first tropical depression of the season formed on July 31st and intensified into Tropical Storm Alex on the morning of August 1st. Alex strengthened into the first hurricane of the season on August 3rd . Seven more tropical cyclones formed in August for a total of eight named tropical cyclones in August. This is a new record for August surpassing the seven named storms in August of 1933 and 1995.

With Tropical Storm Bonnie making landfall near Apalachicola on the Florida Peninsula on August 12th, the un-relenting storm strikes began on Florida. Bonnie was the first of five named storms to make landfall along the Florida coast, four of which were hurricanes. Hurricane Charley in mid-August caused extensive damage to Florida. Charley is now the second costliest tropical cyclone in U.S. history behind Hurricane Andrew in 1992, with estimated total damage near 15 billion dollars. Charley was followed by Frances then Ivan and then Jeanne.

There was a 60% chance this year of the first storm forming after August 1st. This verified when Alex formed from the first tropical depression on August 1st. The other years with the first forming after August 1st in this OCSI phase were 1875, 1897, 1941, 1952, 1962 and 1984.

Each year WRC meteorologists make secondary predictions so this model can be compared with other seasonal predictions. This year the OCSI predicted that there would be at least 7 named storms with 4 of these storms intensifying into hurricanes. Other parameters for the season are given in the following table.

SECONDARY PREDICTIONS: OBSERVED

Number of Storms : 7 13

Number of Hurricanes: 4 8

Number of Hurricane Days: 16 45

Number of Storm Days: 55 60

US Landfalls: 3 9

Cat 3 or Higher Storms: 60% Charley, Frances,

Ivan, Jeanne and Karl

The OCSI is composed of 11 phases which are 9 to 11 years in duration. 2004 was Phase 9 of the OCSI and the years that were used to make the forecast were: 1875, 1886, 1897, 1909, 1921, 1931, 1941, 1952, 1962, 1972, 1984, and 1994. 1909 is another year in this phase of the OCSI and also experienced a very busy season for Florida with 4 storms making landfall. Other active years for the Florida coast in Phase 9 are 1886 when 3 hurricanes make landfall on the west coast of Florida and a 4th hurricane moved just offshore the southeast coast of Florida.

OCSI has been used by Weather Research Center since 1985 to make an outlook for the section of the US coast which has the highest risk of storm landfall. Further research indicates that WRC’s OCSI secondary prediction elements verify better over the past twenty years than Colorado State University’s Atlantic Seasonal Hurricane Activity predictions. WRC’s secondary prediction elements consist of the number of named storms in the Atlantic Basin, number of hurricanes in the Atlantic Basin, number of hurricane days and the number of storm days.

The OCSI indicates that it will be a very busy year in 2005 for the Texas coast and the west coast of Florida which both have a 70% chance of experiencing land falls of a tropical storm or hurricane. Ms. Hasling as a result of new research anticipate a new forecast index in addition to the OCSI. This index will be added to the WRC methodology by the start of the 2005 Atlantic Hurricane Season.

All of WRC's projections including past predictions can be found on the Internet, http://www.wxresearch.com/outlook .

Ms. Hasling and Dr. Freeman are both Fellows and Certified Consulting Meteorologists from the American Meteorological Society as well as members of the NCIM.

 

-30-