Good News for South florida this Year?

[Vortex]

Expert I: More hurricanes this year; Expert II: Not for Florida

By Robert Nolin
Staff Writer
Posted June 1 2005


It's no joke. Hurricane season, which starts today, brings good news and bad news.

The bad news first: A Colorado scientist, with a respectable record of predicting the number of hurricanes each season, sees more storms on the horizon this year. Now the good news: A veteran meteorologist with the National Weather service, whose theory also holds water, says the number of hurricane landfalls is linked to how wet the season's May is, and the month just ended had plenty of rain, which means fewer storms striking Florida.



Either way, experts urge residents to be ready. As last season proved, when an unprecedented four hurricanes roared into the state, anything is possible, they say.

The prognostication was issued Tuesday by William Gray, an atmospheric scientist at Colorado State University. Gray, who has used past weather patterns to predict storm counts for more than 20 years, foresees 15 named storms over the six-month hurricane season. Of those, he expects eight to develop into hurricanes, and four to escalate into intense storms packing winds of 111 miles an hour or more. That's up from his earlier predictions for this year, and more storm activity than last year.

But as many forecasters say, it's not the number of storms that counts, it's where they strike.

Gray calculated the probability of a hurricane hitting the U.S. East Coast, including Florida, at 59 percent, up from the last century's average of 31 percent. The entire U.S. shoreline, including the Gulf of Mexico coast, has a 77 percent chance of a hurricane landfall.

"It looks like it's going to be an active season," Philip Klotzbach, Gray's research associate, said from his Fort Collins, Colo., office. "People should take the necessary precautions."

Klotzbach said this year is a continuation of a decades-long trend of above-average storm seasons that started in 1995. "These phases tend to last between 25 and 40 years," he said.

Weak winds failed to chill the Atlantic this winter, so the warmer water translates into more and fiercer hurricanes. "The warmer water gives them more fuel to develop into storms," Klotzbach said.

In their spring predictions last year, Gray and his colleagues forecast 14 named storms and eight hurricanes, three of them intense. They were close. The actual season saw 15 named storms, nine hurricanes -- four of which struck Florida -- and six intense storms.

The average season has 10 named storms, six hurricanes and two major hurricanes.

But if there's a bright side to the season, it comes from a rainy May. Jim Lushine, a senior meteorologist with the weather service office west of Miami, has studied 75 years of monthly rainfall statistics and found that the rainier the month of May, the fewer hurricanes hit Florida.

This year, May had sufficient rain to predict fewer hits. For Broward, Palm Beach and Miami-Dade counties, the average yearly rainfall is five inches. The month just past, thanks to some last-minute thunderstorms, saw 5.9 inches.

"As the raindrops fall, so do the chances of a South Florida hurricane," Lushine said. "We're about three times as wet this May as we were last year, and that's a nice feeling."

May's rains, Lushine found, indicate the power of the Bermuda High, a high-pressure area over the ocean that, depending on its strength, can push a hurricane toward or away from the state. A lot of rain means the system is weak; a dry May indicates the Bermuda High will be strong enough to push a hurricane toward South Florida.

For example, Lushine said, the second-driest May on record was in 1992 -- when Hurricane Andrew ravaged the state.

Lushine said he's so confident of the rainfall indicator that he's postponing a retirement in which he will live in Alaska part time. "I'll be here for what I think will be a real quiet season," he said. "I'm betting a few months of my retirement time on it."

Gray's prediction of eight hurricanes doesn't address where they may come ashore. Likewise, even the wettest May on record doesn't guarantee a storm won't hit. "There are always unprecedented things that happen," the forecaster said. "People need to prepare this year just like they did last year."

[Brent]

I'm curious... how was May of last year in terms of rainfall?

[gtalum]

"We're about three times as wet this May as we were last year..."

From the article.

[Vortex]

Some of Lushine's comments are just ridiculous in terms of placing so much weight on the Month of May and then were just under an inch of average rainfall given a "last minute thunderstorm" so now were safe here in Florida--PLEASE!



To paraphrase some of the Article:

But if there's a bright side to the season, it comes from a rainy May. Jim Lushine, a senior meteorologist with the weather service office west of Miami, has studied 75 years of monthly rainfall statistics and found that the rainier the month of May, the fewer hurricanes hit Florida.

This year, May had sufficient rain to predict fewer hits. For Broward, Palm Beach and Miami-Dade counties, the average yearly rainfall is five inches. The month just past, thanks to some last-minute thunderstorms, saw 5.9 inches.

"As the raindrops fall, so do the chances of a South Florida hurricane," Lushine said. "We're about three times as wet this May as we were last year, and that's a nice feeling."

May's rains, Lushine found, indicate the power of the Bermuda High, a high-pressure area over the ocean that, depending on its strength, can push a hurricane toward or away from the state. A lot of rain means the system is weak; a dry May indicates the Bermuda High will be strong enough to push a hurricane toward South Florida.

For example, Lushine said, the second-driest May on record was in 1992 -- when Hurricane Andrew ravaged the state.

Lushine said he's so confident of the rainfall indicator that he's postponing a retirement in which he will live in Alaska part time. "I'll be here for what I think will be a real quiet season," he said. "I'm betting a few months of my retirement time on it."

[Brent]

"We're about three times as wet this May as we were last year..."

From the article.

[boca]

If that's the case whose to say that S Fl will not get hit from the South given a weak Bermuda High.That statement was just wrong.

[Blown Away]

Except for Palm Beach, the rest of SFL was below average. I guess it depends on who's rainfall info is used.

http://www.sfwmd.gov/curre/rainmaps/monthly.html

[Trader Ron]

May was VERY dry in Naples. We had 1.46 inches. Half of that fell yesterday.

[sponger]

I don't know about the dry may but alot of fishes would not suprise me. The ITCZ will be farther north than usual allowing storms a chance to head north instead of riding the conveyor belt all the way across.

I agree that it is irresponsible to trumpet "you are safe" Anything goes when these spin up. I think all s2k members will be ready for the worst!

[drudd1]

Ditto that Ron, we were also very dry, with almost all of our monthly total falling here on May 31st.

[Scorpion]

What a load of BS. How can the fact that we got more rain in May make hurricanes turn north? I hear the theory was only correct about 60% of the time.

[SunnyThoughts]

Ron, that goes for those of us in and around the Pensacola area also...after the record setting month of april for rainfall..we had NO rain in May to speak of, until the last few days of the month.

[Air Force Met]

The atmosphere doesn't know whether it's raining on May 31st or June 1st. If the theory is somewhat true...then one might think they should look at the overall rainfall in May...not the last minute showers. If the overall pattern was dry...well...you get the idea.

[Scorpion]

I think the overrall pattern was dry, and most of the rain was big rain events at the beginning of the month and end. From about the 8th-28th or so it was mainly dry.

[StormChasr]

The wet/dry May theory is as valid as the Bermuda High speculations--let's see what actually happens.

[Wpwxguy]

I would have to agree with Air Force Met, the overall pattern for the month would need to be used. A deluge on the last day of the month, does'nt make for a wet May. It was still a very dry May, just caught up on the deficit a little on the last day of the month. Don't be lulled by this theory, it may hold water but one days worth of rain should not have any bearing. IMO

Bill

[sfwx]

http://www.orlandosentinel.com/news/yah ... -headlines

[feederband]

Wet May = Hurricane repellent.

[MWatkins]

I am not sure this is the best message to send to folks as the rest of NOAA and the NHC and others are working their rear-ends off to get the preparedness message out. Basically, what it amounts to, is "I'm not worried why should you be?"

This, unfortunately, is a problem at many levels.

1. 75 years of data is a small size. Too small to draw these comparisons for sure.

2. If we don't have a dynamical model that can predict the steering flow in 5 days time, how can one local forecaster do so 2.5 months in advance?

3. Most of the rainfall that put SFL above normal fell yesterday. So basically, this forecast of "Safeness" is based on one day of rain on the last day of the month? Wha?

4. SST's are well above normal and in fact are dang near the highest on record. These extreemes cannot be represented in the 75 year dataset since this is nearly the HOTTEST on record.

5. The atmosphere is notorious for behaving differently than it has in the past (for details see Dr Gray's elevated landfall and number of hurricane preditions and how much higher they are than the statistical average).

This, sadly, appears to me (complete with the goofy "acxiom") to be one man's effort to put himself above everyone else who is working so hard to get folks prepared. For balance, please note that I took a similar position in July of last season when he was touting "dry may is bad". Just because the outcome worked out in one season, doesn't make it a good prediction.

For another example, look up the words Isaac Cline, Galveston and Hurricane all together in google and see what one man's opinion can do based on some goofy local theory. Frustrating.

Oh yes and you bet your A%#*&^ I will bring this up tonight's show.

MW

[SouthernWx]

If I were a resident of the Florida peninsula, here's something I'd be watching much more closely than the amount of precip falling in the May rain bucket:

MAJOR LANDFALLING FLORIDA PENINSULA HURRICANES SINCE 1870:

Aug 1871
Oct 1873
Aug 1888
Sep 1896
Oct 1906
Oct 1909
Oct 1910
Sep 1919
Oct 1921
Sep 1926
Sep 1928
Sep 1929
Sep 1933
Sep 1935
Oct 1944
Sep 1945
Sep 1947
Sep 1948
Aug 1949
Sep 1950 "Easy"
Oct 1950 "King"
Sep 1960 "Donna"
Sep 1965 "Betsy" (LULL BEGAN)


Aug 1992 "Andrew"


Aug 2004 "Charley" (LULL ENDED)
Sep 2004 "Jeanne"

Between 1870 and 1965 (95 yrs), 23 major hurricanes impacted the Florida peninsula....an average of once every 4.1 years (and the 1846-1965 return period was a major impact once every 4.5 years).

UNTIL 2004, only ONE (1) major hurricanes impacted the Florida peninsula (Andrew) during the 1966-2003 period (38 yrs); an average return period of an astounding once every 38 years.

I can't say with certainty that a major hurricane will strike some portion of central or south Florida in 2004, but do have overwhelming confidence that many more intense hurricanes will impact this area during the next 40 year period of record than have occurred during the past forty. Nature ALWAYS balances out the scales....whether it's regarding temperature, precip, or hurricanes.

PW