Extended range hurricane forecast for 2006

[ecopal]

http://hurricane.atmos.colostate.edu/Forecasts/2006/april2006/

EXTENDED RANGE FORECAST OF ATLANTIC SEASONAL HURRICANE ACTIVITY AND U.S. LANDFALL STRIKE PROBABILITY FOR 2006

We continue to foresee another very active Atlantic basin tropical cyclone season in 2006. *Landfall probabilities for the 2006 hurricane season are well above their long-period averages.
(as of 4 April 2006)

By Philip J. Klotzbach [1] and William M. Gray [2]
with special assistance from William Thorson [3]

*This forecast as well as past forecasts and verifications are available via the World Wide Web at
http://hurricane.atmos.colostate.edu/Forecasts

PROBABILITIES FOR AT LEAST ONE MAJOR (CATEGORY 3-4-5) HURRICANE LANDFALL ON EACH OF THE FOLLOWING COASTAL AREAS:

1) ***** Entire U.S. coastline - 81% (average for last century is 52%)

*2) ***** U.S. East Coast Including Peninsula Florida - 64% (average for last century is 31%)

*3) ***** Gulf Coast from the Florida Panhandle westward to Brownsville - 47% (average for last century is 30%)

4) ***** Above-average major hurricane landfall risk in the Caribbean


ABSTRACT
Information obtained through March 2006 continues to indicate that the 2006 Atlantic hurricane season will be much more active than the average 1950-2000 season. *We estimate that 2006 will have about 9 hurricanes (average is 5.9), 17 named storms (average is 9.6), 85 named storm days (average is 49.1), 45 hurricane days (average is 24.5), 5 intense (Category 3-4-5) hurricanes (average is 2.3) and 13 intense hurricane days (average is 5.0). *The probability of U.S. major hurricane landfall is estimated to be about 55 percent above the long-period average. *We expect Atlantic basin Net Tropical Cyclone (NTC) activity in 2006 to be about 195 percent of the long-term average.

Discussion
There is no physical basis for assuming that global hurricane intensity or frequency is necessarily related to global mean surface temperature changes of less than ? 0.5 oC. *As the ocean surface warms, so too does global upper air temperatures to maintain conditionally unstable lapse-rates and global rainfall rates at their required values. *Seasonal and monthly variations of sea surface temperature (SST) within individual storm basins show only very low correlations with monthly, seasonal, and yearly variations of hurricane activity. *Other factors such as tropospheric vertical wind shear, surface pressure, low level vorticity, mid-level moisture, etc. play more dominant roles in explaining hurricane variability than do surface temperatures. *

Although there has been a general global warming over the last 30 years and particularly over the last 10 years, the SST increases in the individual tropical cyclone basins have been smaller than the overall global warming (about half) and, according to the observations, have not brought about any significant increases in global major tropical cyclones except for the Atlantic which as has been discussed, has multi-decadal oscillations driven primarily by changes in Atlantic salinity. *** No credible observational evidence is available or likely will be available in the next few decades which will be able to directly associate global surface temperature change to changes in global hurricane frequency and intensity. *

*

Most Southeast coastal residents probably do not know how fortunate they had been in the prior 38-year period (1966-2003) leading up to 2004-2005 when there were only 17 major hurricanes (0.45/year) that crossed the U.S. coastline. *In the prior 40-year period of 1926-1965, there were 36 major hurricanes (0.90/year or twice as many) that made U.S. landfall. *It is understandable that coastal residents were not prepared for the great upsurge in landfalling major hurricanes in 2004-2005.

*

We should interpret the last two years of unusually large numbers of U.S. landfalling hurricanes as natural but very low probability years. ** During 1966-2003, U.S. hurricane landfall numbers were substantially below the long-term average. *In the last two seasons, they have been much above the long-term average. *Although the 2004 and 2005 hurricane seasons have had an unusually high number of major landfall events, the overall Atlantic basin hurricane activity has not been much more active than five of the recent hurricane seasons since 1995 (e.g., 1995-1996, 1998-1999, 2003). *What has made the 2004-2005 seasons so unusually destructive is the higher percent of major hurricanes which moved over the U.S. coastline. *These landfall events were not primarily a function of the overall Atlantic basin net major hurricane numbers, but rather of the favorable broad-scale Atlantic upper-air steering currents which were present the last two seasons. *It was these favorable Atlantic steering currents which caused so many of the major hurricanes which formed to come ashore. *

Please visit our website at http://www.e-transit.org/hurricane for landfall probabilities for 11 U.S. coastal regions, 55 subregions and 205 coastal and near-coastal counties from Brownsville ,Texas to Eastport ,Maine .





*Table 9: Estimated probability (expressed in percent) of one or more U.S. landfalling tropical storms (TS), category 1-2 hurricanes (HUR), category 3-4-5 hurricanes, and total hurricanes and named storms along the entire U.S. coastline, along the Gulf Coast (Regions 1-4), and along the Florida Peninsula and the East Coast (Regions 5-11) for 2006. *The long-term mean annual probability of one or more landfalling systems during the 20 th century is given in parentheses. *

*

Coastal
Region TS Category 1-2 Category 3-4-5 All Named Storms

Entire U.S.
(Regions 1-11) 91% (80%) 88% (68%) 81% (52%) 98% (84%) 99%(97%)

Gulf Coast
(Regions 1-4) 74% (59%) 61% (42%) 47% (30%) 79% (61%) 95% (83%)

Florida plus East Coast
(Regions 5-11) 64% (51%) 69% (45%) 64% (31%) 89% (62%) 96% (81%)

*
Even though we expect to see the current active period of Atlantic major hurricane activity to continue for another 15-20 years, it is statistically unlikely that the coming 2006 and 2007 hurricane seasons, or the seasons which follow, will have the number of major hurricane U.S. landfall events as we have seen in 2004-2005.

*

*

 

[KISH7374]

I had heard that the majority of the storms this year are going to hit the Carolinas and up north east.

 

[SlowMovin]

Dr. Gray is pretty good. I've been reading his forecasts for some time now.

A while back, I was getting tired of hearing people saying "they're predicting a bad hurricane year". I'd been hearing that every year since Andrew, and it rarely happened. So I decided to go back and run some statistical analyses on the predictions.

The only "expert" I could find who provided his past predictions was Dr. Gray. When I looked at them over time, I was surprised to find he was much more accurate than I'd expected. I don't know about the rest of "them", but this guy is good.

Here's one more quote from the forecast ecopal referenced...

It is rare to have two consecutive years with such a strong simultaneous combination of high amounts of major hurricane activity together with especially favorable steering flow currents. The historical records and the laws of statistics indicate that the probability of seeing another two consecutive hurricane season like 2004-2005 is very low.

Here's hoping he's right. But I'm still going to prepare, just in case.

 

[ecopal]

Dr. Gray is pretty good. I've been reading his forecasts for some time now.

A while back, I was getting tired of hearing people saying "they're predicting a bad hurricane year". I'd been hearing that every year since Andrew, and it rarely happened. So I decided to go back and run some statistical analyses on the predictions.

The only "expert" I could find who provided his past predictions was Dr. Gray. When I looked at them over time, I was surprised to find he was much more accurate than I'd expected. I don't know about the rest of "them", but this guy is good.

Here's one more quote from the forecast ecopal referenced...

Here's hoping he's right. But I'm still going to prepare, just in case.

Thanks for your interesting analysis about Dr. Gray's prediction record.

My interpretation of Dr. Gray's report is that this will be an above average hurricane year for all areas, but Southern florida and The East Coast are predicted to have about twice their normal risk of having a major hurricane this summer.

It is also interesting to note that the AccuWeather forecast of March 2006
http://wwwa.accuweather.com/promoti...=aw&page=nehurr
suggested that the highest risk for hurricanes this summer would be on the East Coast and Upper Texas coast.

I have done considerable preparation for a hurricane this year, but according to both these predictions there are other places that may have more reason to worry than we do.

 

[yippie]

Can't access the accuweather page. Error message says page cannot be found.

 

[ecopal]

This address does not work on some internet software. I will just post the article.

http://wwwa.accuweather.com/promotion.asp?dir=aw&page=nehurr

Threat of Major Hurricane Strike Grows for Northeast

AccuWeather.com Warns That "Weather Disaster of Historic Proportions" Could Strike as Early as This Year

(New York, NY - March 20, 2006) - The northeast U.S. coast could be the target of a major hurricane, perhaps as early as this season, according to research announced today by the AccuWeather.com Hurricane Center. In terms of number of storms, the 2006 hurricane season will again be more active than normal, but less active than last summer's historic storm season.

"The Northeast is staring down the barrel of a gun," said Joe Bastardi, Chief Forecaster of the AccuWeather.com Hurricane Center. "The Northeast coast is long overdue for a powerful hurricane, and with the weather patterns and hydrology we're seeing in the oceans, the likelihood of a major hurricane making landfall in the Northeast is not a question of if but when."

AccuWeather.com Hurricane Center research meteorologists have identified weather cycles that indicate which U.S. coastal areas are most susceptible to landfalls. "If you examine past weather cycles that have occurred in the Atlantic, you will see patterns of storms," added Ken Reeves, Expert Senior Meteorologist and Director of Forecasting Operations at AccuWeather.com. "Determination of where we are in the cycle has enabled AccuWeather.com meteorologists to accurately predict hurricane activity in Florida in 2004 and along the Gulf Coast last year. There are indications that the Northeast will experience a hurricane larger and more powerful than anything that region has seen in a long time."

The current cycle and above-normal water temperatures are reminiscent of the pattern that eventually produced the 1938 hurricane that struck Providence, R.I. That storm killed 600 people in New England and Long Island. The 1938 hurricane was the strongest tropical system to strike the northeastern U.S. in recorded history, with maximum gusts of 186 mph, a 15- to 20-foot storm surge and 25- to 50-foot waves that left much of Providence under 10-15 feet of water. Forecasters at AccuWeather.com say that patterns are similar to those of the 1930s, 40s and 50s when storms such as the 1938 hurricane, the 1944 Great Atlantic Hurricanes and the Trio of 1954--Carol, Edna and Hazel--battered the coast from the Carolinas to New England. The worry is that it will be sooner, rather than later, for this region to be blasted again.

Additionally, AccuWeather.com believes that the upper Texas coast is likely to be the target of higher than normal hurricane and tropical storm activity over the next 10 years. "Hurricane Rita was a warning shot," says AccuWeather.com's Bastardi, referring to the 2005 Category 5 storm that threatened the Houston area and made landfall near the Texas-Louisiana border last September. "The Texas coast is in for a long period of tropical activity, particularly the region from Corpus Christi to Sabine Pass at the Louisiana border."

According to AccuWeather.com, the 2006 tropical storm season will still be more active than normal, but less active than last year, with fewer storms than 2005's record 26 named storms and 14 hurricanes.

However, the threat of a devastating storm striking the most densely populated part of the United States is of serious concern, particularly coming so soon after Hurricane Katrina, one of the deadliest weather disasters in U.S. history.

The 1938 hurricane resulted in more than $306 million in damage which, when adjusted for inflation, would total nearly $6 billion today. Because coastal areas are much more developed and populous today, a similar storm would result in substantially higher damage despite government efforts to protect U.S. citizens and property.

By comparison, insurance claims resulting from damage due to Hurricane Katrina have been estimated at $23 billion, making it the costliest storm in U.S. history. The density and value of developed property in the northeastern U.S. means that the damage from a direct hit from a major storm similar to the 1938 hurricane might conceivably rival or surpass that of Hurricane Katrina.

Because a hurricane of this magnitude has not made landfall in the northeastern U.S. in nearly 60 years, few Americans are even aware that hurricanes can and do directly impact this part of the country. Because most hurricanes in the last 50 years have been a southern U.S. phenomenon, preparedness for a major hurricane along the Northeast coast is not as thorough. But the storm that struck Providence on Sept. 21, 1938, traveled northward along the Gulf Stream and first made landfall in Westhampton, Long Island before ripping a path across the island and continuing north to Rhode Island. That storm is still regarded as the greatest weather disaster in Long Island history. It altered the Long Island coastline, created the Shinnecock Inlet, and has since been known as "the Long Island Express." Many meteorologists believe that the next time a storm like "the Long Island Express" hits the Northeast coast, it could become the greatest natural disaster in U.S. history.