The hurricane season is officially over, so it's time for the annual Hurricane Season Summary. I sent out about 80 updates to my 27-member mailing list over the past 6 months (wow, that's a lot!); now it's time for the final one. I'm going to format the summary in the same fashion as I did last year, so it might even look a bit familiar if you were a subscriber last year. I will keep the same basic outline: the Saffir-Simpson Scale, Lifetimes and Intensities, Climatology, and Landfall. As usual, my data and typing could contain errors, so if you see a mistake, please point it out to me.
Saffir-Simpson Scale of Tropical Cyclone Intensity
------------------- ---------- ------------------
depression 23- 39 N/A
tropical storm 40- 73 N/A
1 74- 95 > 980
2 96-110 965-979
3 111-130 945-964
4 131-155 920-944
5 >156 < 919
1. Lifetimes and Intensities
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NAME DATES OF MAX WIND MIN PRES
ACTIVITY (mph) (mb)
-------- --------------- ------------ -------------
ARLENE 11 JUN - 18 JUN 60 1000
TD2 03 JUL - 03 JUL 35 1004
BRET 18 AUG - 23 AUG 140 945
CINDY 19 AUG - 31 AUG 140 944
DENNIS 24 AUG - 05 SEP 105 962
EMILY 24 AUG - 28 AUG 65 1004
TD7 05 SEP - 07 SEP 35 1005
FLOYD 07 SEP - 17 SEP 155 921
GERT 11 SEP - 23 SEP 150 930
HARVEY 19 SEP - 22 SEP 60 995
TD11 04 OCT - 06 OCT 35 1002
TD12 06 OCT - 08 OCT 35 1007
IRENE 13 OCT - 19 OCT 105 958
JOSE 17 OCT - 25 OCT 100 977
KATRINA 28 OCT - 01 NOV 40 999
LENNY 13 NOV - 21 NOV 155 929
2. Climatology and Statistics
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The average annual number of tropical disturbances (over the past 53 years) is:
9.9 named storms
5.9 hurricanes
2.5 major hurricanes
This year, the numbers were well above that average (which has recently been the trend, except 1997)
12 named storms (14 in 1998)
8 hurricanes (10 in 1998)
5 major hurricanes (3 in 1998)
Interestingly, all 5 major hurricanes were CAT4's. There were no storms that peaked at CAT3, and none reached CAT5. It is quite rare to have 4 CAT4's in one season... the most recent year I could find that came close was 1995 with 3 of them: Felix, Luis, and Opal. You have to go back a long way before 1995 to find another comparable year (1961 had 2 CAT4's and 2 CAT5's).
There were a total of 77 named storm days (days during which a named storm was present). 43 of those days were "hurricane days", and 15 of those days were "intense hurricane days". This is 193% of the climatological mean, i.e., this season was about twice as active as the "normal" season. The average numbers are 46.9 named storm days, 23.7 hurricane days, and 4.7 intense hurricane days.
Here is a summary of highlights (VERY brief):
Arlene never made it to hurricane status, but started the season off very early, the afternoon of June 11.
Bret formed in the southern Bay of Campeche and eventually reached CAT4 before making landfall on an unpopulated region of Texas' south coast. His persistent northward motion was missed by the models that all took him westward into Mexico near Tampico.
Cindy never got close to land, but is worth mentioning because she formed so far east (19.4W). Only a handfull of storms have ever formed east of 20W.
Dennis formed just east of the Bahamas, approached the US, then headed out to sea... but not too far. He lingered off the coast of Cape Hatteras, NC for almost a week before moving westward again and making landfall just north of Cape Lookout, NC.
Floyd was tied for the most powerful storm of the year. He formed in the central Atlantic in the first week of September. Winds reached 155mph as he passed over the Bahamas, then continued his journey making US landfall as a CAT2 on Cape Fear, NC. Floyd caused incredible flooding in many of the eastern states, especially NC.
Harvey and Irene were both fairly weak storms (Harvey never even reached hurricane status), and both made landfall on the western side of the southern Florida peninsula, in the Everglades. Both storms were also forecast by models to hit the Tampa region... both stayed further south.
Jose formed very far south (10N) in the third week of October. He peaked at CAT2 intensity just as he passed over the northern Leeward Islands.
Lenny was tied with Floyd for the most powerful hurricane of the year. He formed in the western Caribbean Sea, then moved EASTWARD across the Caribbean, strengthening to a CAT4 storm with 155mph winds. He stalled over the northern Leeward Islands for 2 days, causing immense destruction. Models were initially reluctant to even make him a hurricane. That changed quickly. Lenny was the first storm of such intensity to move eastward across the Caribbean. Also, he was only the 5th major November hurricane since records began in 1886.
From Aug24 to Aug28, there were three named storms in the Atlantic, Cindy, Emily, and Dennis. Not too outstanding, but it was the most active time frame of the season (last year, there were 4 active hurricanes at the same time). Other multi-storm periods this year were: 1) Floyd and Gert were both active between 11Sep and 17Sep; 2) Gert and Harvey were both active between 19Sep and 22Sep; 3) Jose and Irene were both active between 17Oct and 19Oct. Basically, the point is that the season came in bursts of activity.
3. Landfall
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There were 10 landfalling storms this year... only 5 of which made landfall on the US. Compare this to last year, when 7 of 14 named storms made landfall, and all 7 landfalls were on the US (at some point).
The first column is the storm name, second column is the date of landfall, third column is the approximate local time of landfall, fourth column is max winds (mph) at landfall, and the fifth column is the nearest location to landfall.
TD2 7/3 0000 35 Nautla, Mexico
BRET 8/22 1800 125 Padre Island, TX
DENNIS 9/4 1700 70 Cedar Island, NC
TD7 9/6 1000 35 just N of Cuidad Madero, Mexico
FLOYD 9/14 1700 140 Great Abaco Island, Bahamas
9/16 0300 110 Cape Fear, NC
HARVEY 9/21 1700 50 Chokoloskee, FL (Everglades)
IRENE 10/14 0900 75 Cape Sable, FL (Everglades)
JOSE 10/20 1200 100 Antigua
10/21 0800 75 US Virgin Islands
KATRINA 10/29 0800 40 Puerto Cabezas, Nicaragua
10/31 0100 30 Xkalak, Mexico
LENNY 11/18 1300 135 Anguilla, St.Maarten, St.Bartelemy
11/19 2300 70 Antigua
Thanks to everyone who read the updates, to those who provided the list with weather conditions/updates when the storms hit land, and to those who provided me with feedback about the updates. I also want to thank fellow CSU-ite Eric Blake for proofreading this message and supplying me with the climatological "storm days" data used in Section 2.
One more hurricane season left in the millenium. Until then, stay safe and have a great winter and spring. Hurricane Season 2000 begins June 1, the first name in the lineup is Alberto.
Please visit my tropical Atlantic headquarters.
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