why wasnt 1998 very active compared to 1995

[year_2005]

It only had 14 storms (which is actually above average ) but looking at the warm ssts in the atlantic that year and the la nina, why wouldnt we have more? is it because there was still warm water in the far East pacific(by central america) and also north of the equator as the la nina gradually developed?

[KWT]

Probably left over from the strong El Nino of 1997/1998.

Also worth noting it started late as well not really picking up till mid August.

Finally if you have the time look up Accumlated cycle energy (ACE) and you'll find 1998 was actually what we call a hyperactive season, along with 1995 and 2004, 2005 as well as others.

[Ptarmigan]

I am thinking left over from the strong El Nino. When you look at ACE per storm on average, the 1998 average ACE was 13, while 1995 average ACE was 12. The most active season, 2005 had an average ACE was 9. 2004 had an average ACE was 16 (Nicole was a subtropical storm).

1995
228/19=12

1998
182/14=13

2004
225/14=16.07

2005
248/27=9.19

2008
145/16=9.06

[bvigal]

1998 not very active? Hmm, overall storm numbers may not be the best measuring stick, as KWT and Ptarmigan have pointed out using ACE. 2 storms in 1998 were historic. Mitch touched me in a very personal way, so it sticks in my mind quite clearly. Though by any measurement, it was a monster!

And, I'm sure Luis (cycloneye) will never forget GEORGES! I still lived on the mainland then, but at a conference chatted with a lady from Puerto Rico who told me Georges went E-W across the entire island, and left no leaves on the trees. Puerto Rico is not small... that is amazing!

There is some interesting history you might want to read. The following is from NHC's 1998 summary.

Hurricane Mitch
Mitch is responsible for over nine thousand deaths predominately from rain-induced flooding in portions of Central America, mainly in Honduras and Nicaragua. This makes Mitch one of the deadliest Atlantic tropical cyclones in history, ranking only below the 1780 "Great Hurricane" in the Lesser Antilles, and comparable to the Galveston hurricane of 1900, and Hurricane Fifi of 1974, which primarily affected Honduras.

The 905 mb minimum central pressure and estimated maximum sustained wind speed of 155 knots over the western Caribbean make Mitch the strongest October hurricane (records began in 1886). Mitch moved across the Yucatan Peninsula and southern Florida as a tropical storm.
...
The estimated death toll from Mitch currently stands at 9,086 . Fact Sheet #21 from the U.S. Agency for International Development (Table 6), as of December 1998, compiled the following death totals: Honduras, 5677; Nicaragua, 2,863; Guatemala, 258; El Salvador; 239; Mexico, 9 and 7 in Costa Rica. The death toll also includes 31 fatalities associated with the schooner Fantome. In addition, another 9191 persons were listed as missing .

Mitch also claimed two lives in Monroe County, Florida. Both deaths were drowning-related incidents resulting from a fishing boat capsizing.

It has been estimated that there was a 50 percent loss to Honduras' agricultural crops. At least 70,000 houses were damaged and more than 92 bridges were damaged or destroyed. There was severe damage to the infrastructure of Honduras and entire communities were isolated from outside assistance. To a lesser extent, damage was similar in Nicaragua, where a large mudslide inundated ten communities situated at the base of La Casitas Volcano. Guatemala and El Salvador also suffered from flash floods which destroyed thousands of homes, along with bridges and roads.

The Florida tornadoes injured 65 people and damaged or destroyed 645 homes.

Mitch special imagery from NOAA's OSE lab.
*note: Reliefweb fixed death toll at 10,530 with 10,721 missing. see http://www.hurricanemitch.com

Hurricane Georges
Georges (pronounced Zhorzh) was the second deadliest and second strongest hurricane within the Atlantic basin during the 1998 season. Its 17 day journey resulted in seven landfalls, extending from the northeastern Caribbean to the coast of Mississippi, and 602 fatalities -- mainly in the Dominican Republic and Haiti.
...
In Puerto Rico, there was considerable damage to homes throughout the island. A total of 72,605 homes were damaged, of which 28,005 are estimated to have been completely destroyed. During the hurricane, over 26,000 people were in shelters. In the Dominican Republic upwards of 185,000 were left homeless by Georges and 100,000 remained in shelters through mid-October as electricity and water service remain out in most of the country. Across Haiti, government officials stated that 167,332 had been left homeless by the hurricane.

The agricultural industry in Puerto Rico was hit hard by Georges with estimates of 95% of the plantain and banana crop destroyed along with 75% of the coffee crop.

[KWT]

Hurricane Georges was an amazing hurricane with regards to just how many landfalls the system made, if there is a system that really did rake the Caribbean, that one was it.

[Macrocane]

For me 1998 it's like 2004, the number of storms may not have been the highest on record but the storms were strong, longe-lived and had long tracks and that made them hyperactive seasons. To answer the question, I think that 1998 was not as active as 2005 because the SST were a little cooler and because the effects of the very strong 1997-98 El Niño inhibited development on the basin for the first 2 months, besides I believe that there are things that we still don't understand about the dynamic and thermodynamics of the atmosphere and some of those things make some seasons more active tan others even when they have similar characteristics.

[Ptarmigan]

I came up with a formula based on how many times a storm makes landfall and how many people died, which includes direct, indirect, and missing. I called it the Impact Score and I find it a good way to gauge how active the season really is based on impact.

The formula is:
Wind Speed in Knots Based On Impact/Landfall Sum of Square * Number of deaths and missing * 2^How Many Times The Storm Made Landfall * Peak Wind / 1000000

Example:
Hurricane Ike (2008)
(110^2 + 115^2 + 70^2 + 95^2) * 195 * 2^4 * 125 / 1000000 = 15307.5
Total Impact (Landfall or Not) Death Toll Landfall Point Peak Wind

It is still a work in progress and would like to include normalized damage figure.

Normalized Damage
http://www.nhc.noaa.gov/pdf/NormalizedHurricane2008.pdf

[bvigal]

Ptarmigan, that sounds like a great project! Since 1998 has been brought up, thinking of Mitch, it was the rainfall that caused the huge death toll. Perhaps you can add a variable for rainfall totals?

[Ptarmigan]

Ptarmigan, that sounds like a great project! Since 1998 has been brought up, thinking of Mitch, it was the rainfall that caused the huge death toll. Perhaps you can add a variable for rainfall totals?

I certainly would like to add that. However, some storms, especially from years ago do not have any rainfall total.