Question about Hurricane David

[EDR1222]

I was reading some information on David from 1979. I noticed where, according to information it was a category 5 before coming ashore on the Dominican Republic. If this is true, does the storm hold any records for the intensity it attained in that particular region?

I know some of the stronger Cat-5's have occured a little further west of where David was such as Mitch, Allen, Gilbert, and Ivan. Of course the Labor Day Storm, Camille, and Andrew were also in different areas of the basin.

Just wondering if anyone had any thoughts or information on this.

Comments also welcome

Thanks,

Ed

[Derek Ortt]

Allen and Ivan had a lower pressure than David in that region (David had a 924, while Allen and Ivan were at 911)

I am suspicious of the cat 5 rating of David. Intensities of the major hurricanes seem to have been overstated during that time period

[EDR1222]

Yeah I was wondering about that too Derrick.

Thanks for the info

[recmod]

I don't know why some sites list David as a Cat 5. I have every advisory on that storm and never did the winds get above 150mph. If it was upgraded to a Cat 5, this was another one of those "after-the-fact" deals.

--Lou

[Derek Ortt]

I believe David's peak wind speed was 150KT, not m.p.h. (though 150 m.p.h. seems more reasonable).

Most of the old information is based upon knots, not m.p.h.

[recmod]

Sorry Derek, but I have all the printed advisories from David and they use mph, not knots for the wind speed. During 1979, I was doing a college thesis and, being a meteorology major, used the current hurricane season for my project. I worked with the weather service and got hard copies of all the advisories for every storm that year. David never exceeded 150 mph in any advisory. The storm reached that windspeed twice; first as it approached the Windward/Leeward Islands and again just before making landfall in Hispaniola. The hurricane weakened slightly over the Eastern Caribbean to 140 mph.

--Lou

[Derek Ortt]

The advisory information then may have been revised during the best track, which typically happens (such as Ivan's landfall being lowered from 130 m.p.h. to 120 m.p.h.)

[HUC]

Where i can obtain the advisories on David1979,that caused a lot of damages here in the central carribean Thank's

[Alacane]

Hi Recmod, do you have those advisories posted on a website somewhere? Living in Mobile, I would like to see the advisories on Frederic. Thanks.

[EDR1222]

This information is from hurricanetrack.com. If you hover over the locations prior to landfall in the Dominican Republic, the reports say it was a category 5.

http://www.hurricanetrack.com/JavaHist/

Ed

[EDR1222]

Just pull up 1979 then select David.

Ed

[Anonymous]

David was 150 mph/924 mb. Somebody once typed 150 KT instead of MPH< and messed things up.

[Scorpion]

You sure? I always heard he was a Cat 5.

[Anonymous]

The Report from the NHC said David hit the DR at 125 kt...or 145 mph, after peaking at 150 mph/924 mb. They also mention how "David was the strongest storm to hit this area since 1930..." and the 1930 storm was 150 mph.

[Derek Ortt]

ftp://ftp.nhc.noaa.gov/pub/storm_archiv ... elim03.gif

its 150KT for the Carib, not 150 m.p.h.

However, they used the FL winds as equal to the surface winds. 135-140KT seems more realistic than 150KT

[EDR1222]

Seems like according to the report of 150 knots at flight level that 135 to 140 knots is just about right. Sounds like David might could have been a borderline 4-5 for part of his life.

Thanks for all the input on this everyone.


Ed

[recmod]

I am not trying to be argumentative or dispute the data that others have presented regarding Hurricane David....but, I KNOW that David was never upgraded to a Cat 5 hurricane while it was an active storm. It is possible that some NHC official decided in post-storm re-analysis (ala Andrew) that David deserved Cat 5 status. The storm, during all the officially issued NHC advisories, was NEVER listed as having winds any higher than 150 MPH. The data as is listed today on such sites as Unisys is not accurate for Hurricane David.
The Unisys advisory archive for David shows other inconsistencies from the official advisories. Unisys shows David downgraded to a 70mph tropical storm after exiting Hispaniola. The storm was never lowered below 75mph and was never downgraded in an official advisory. Was this not done for the sake of consistency and the fear that downgrading the storm would lower the public interest, creating a potentially dangerous situation since the storm was forecast to re-intensify??? I don't know.

In addition to this, the Unisys site does not show the correct amount of re-intensification that occured over the Bahamas. According to Unisys, David only reintensified to 100mph...but the official advisories brought David up to 110mph, before a weakening trend set in prior to the Florida landfall (down to 90mph)

I don't know much about the Unisys site. What is the source of their data that they present in their archives??

At the risk of starting another debate, I see that they (Unisys) also have Hugo listed as a Cat 5 hurricane. This is another storm that was never given a Cat 5 designation during its active lifetime. Was there a Post-storm analysis done here also??

I began tracking hurricanes in 1977, keeping records of every advisory issued by the NHC. The ONLY hurricanes since 1977 that ever reached Cat 5 status were:

1977: Anita
1980: Allen
1988: Gilbert
1992: Andrew (upgraded 10 years later)
1998: Mitch
2003: Isabel
2004: Ivan

It's interesting to note that Unisys also lists Andrew as a Cat 5 hurricane...but not at the same point in its track as the NHC. The hurricane was officially upgraded to a Cat 5 storm after studies showed that Andrew strengthened just before landfall in south Florida. Unisys shows Andrew reaching 170 mph a full 12-14 hours earlier, when the storm was centered at 25.4N, 75.8W.


It almost seems that there is a recurring tendency to over-state historical hurricane's intensities. These storms were bad enough without having to over-dramatize for the sake of sensationalism.

Any comments??

--Lou

[Derek Ortt]

The Unisys site shows <b>BEST TRACK</b> information, not advisory information. Advisory information is considered to be an unofficial estimate and cannot be used in any scientific publication.

As for the weakening before FL, there was not any. What happened was and the NHC explains what happened in their tropical cyclone report was that the recon made a big mistake in reporting a 965mb pressure (like that bogus Frances pressure of 951mb 6 hours before landfall).

As for Hugo, it is very well documented that the first recon aircraft did find a category 5 hurricane, and this took the recon by surprise, nearly killing many HRD scientists on board as a cat 3 storm was anticipated.

The unisys data is correct regarding best track intensity. The advisories are merely estimates and should be ignored when there is contradiction regarding the Best Track and changes are typically made after the season when a thorough analysis of all of the data can be performed

[Derek Ortt]

also regarding Andrew, peak winds have officially been set to 175 m.p.h. when it was just east of the Bahamas, in accordance to flight level winds of about 170KT. Also, winds at Louisiana landfall were lowered from 105KT to 100KT

[*StOrmsPr*]

1979 David
150kt prios to landfall 924mb
ftp://ftp.nhc.noaa.gov/pub/storm_archives/atlantic/prelimat/atl1979/david/prelim03.gif


1989 Hugo
140kt 918mb east of leeward islands

ftp://ftp.nhc.noaa.gov/pub/storm_archiv ... elim02.gif