Page 1 of 2 12 LastLast
Results 1 to 15 of 19

Thread: Hurricane Dean and Bogus Reporting

  1. #1
    Principal Partner
    Join Date
    Dec 2004
    Location
    Annapolis, MD
    Posts
    1,294

    Hurricane Dean and Bogus Reporting

    I am having a very hard time reconciling the 160kt winds reported on the TV news and the actual bouy observations from NOAA. If I go here:

    http://www.ndbc.noaa.gov/station_page.php?station=42056

    I see the max gust at 2250 gmt as 58.3 kts, At that same time the weather channel is reporting the hurricane to be located just 1.7 miles from this buoy. I compared lat lon of the buoy with lat lon of the hurricane.

    I have done this several times for several hurricanes in several locations. Tried to substantiate these claims of 100-150 kt winds with actual observations from NOAA sites. I have never found one that was even close. I look at a 24 hour history of wind gusts and never see anything even approaching the numbers the guys on TV say. Any weather experts out there want to show me where I can see that it actually blew 150kts someplace in the Caribbean during this storm or any other?

    I'm not saying these storms are anything to mess with and don't want to trivialize their power but I feel like I am being fed a bunch of crap by the weather jocks looking to sensationalize story.

  2. #2
    Principal Partner Shadowfax's Avatar
    Join Date
    Mar 2005
    Location
    Rock Hall, MD Home, New Hope, PA
    Posts
    412
    Here, Here! I agree. The Weather Channel has been dying for a hurricane and now that they have one they are going nuts 150 mph winds would pick you up and set you down in the next county and these guys are standing on the beach with a camera crew. I think in this case they just can't get close enough to where the center of the storm is/was so they make due with what they can get standing in front of a hotel.

    I don't know about the sea buoys, but NOAA published the following, so there is wind out there somewhere.

    000
    WTNT44 KNHC 210900
    TCDAT4
    HURRICANE DEAN DISCUSSION NUMBER 33
    NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
    500 AM EDT TUE AUG 21 2007

    DEAN MADE LANDFALL ON THE EAST COAST OF THE YUCATAN PENINSULA NEAR
    THE CRUISE SHIP PORT OF COSTA MAYA AROUND 0830 UTC...AND THE EYE IS
    NOW JUST INLAND. OBSERVATIONS FROM AN AIR FORCE HURRICANE HUNTER
    PLANE INDICATE THAT THE HURRICANE WAS INTENSIFYING RIGHT UP TO
    LANDFALL. A PEAK FLIGHT-LEVEL WIND OF 165 KT WAS MEASURED JUST
    NORTH OF THE EYE. MAXIMUM SURFACE WINDS FROM THE SFMR WERE 124
    KT...BUT IT IS HIGHLY LIKELY THAT THE MAXIMUM SURFACE WIND SPEED
    WAS NOT REPORTED BY THE SFMR INSTRUMENT. A GPS DROPSONDE IN THE
    NORTHERN EYEWALL MEASURED A WIND SPEED OF 178 KT AVERAGED OVER THE
    LOWEST 150 METERS OF THE SOUNDING. BASED ON THE DROPSONDE AND THE
    FLIGHT-LEVEL WINDS...THE INTENSITY IS SET AT 145 KT. A DROPSONDE
    IN THE EYE MEASURED A CENTRAL PRESSURE OF 906 MB JUST PRIOR TO
    LANDFALL. SOME HISTORIC NOTES ARE IN ORDER HERE. THE 906 MB
    CENTRAL PRESSURE IS THE NINTH LOWEST ON RECORD FOR AN ATLANTIC
    BASIN HURRICANE...AND THE THIRD LOWEST AT LANDFALL BEHIND THE 1935
    LABOR DAY HURRICANE IN THE FLORIDA KEYS AND HURRICANE GILBERT OF
    1988 IN CANCUN MEXICO. DEAN IS ALSO THE FIRST CATEGORY FIVE
    HURRICANE TO MAKE LANDFALL IN THE ATLANTIC BASIN SINCE ANDREW OF
    1992.

    FORECAST POSITIONS AND MAX WINDS

    INITIAL 21/0900Z 18.7N 87.8W 145 KT
    12HR VT 21/1800Z 19.1N 90.4W 85 KT...INLAND
    24HR VT 22/0600Z 19.6N 93.9W 95 KT...OVER BAY OF CAMPECHE
    36HR VT 22/1800Z 20.1N 96.8W 105 KT...INLAND
    48HR VT 23/0600Z 20.5N 100.0W 25 KT...INLAND...DISSIPATING
    72HR VT 24/0600Z...DISSIPATED.

    I tend to believe these people over the Weather Channel, even if they can't seem to get the weekend weather right

    Paul Raywood
    s/v Shadowfax
    1988 E34 #257
    Rock Hall, Maryland, Home Port
    New Hope, Pennsylvania, Home

  3. #3
    Principal Partner
    Join Date
    Dec 2004
    Location
    Annapolis, MD
    Posts
    1,294

    I still dont get it

    Why whould the buoy I refereced in my first post not have recorded higher surface winds? The buoy only showed 58 kts and nothing higher over the past 24hours? I can see upper level winds say at the altitude a plane is flying at being 150kts but I have never seen a NOAA buoy record anything even close to that in all the hurricanes I have followed. I still want to see the site that actually observed and recorded 150kts.

  4. #4
    Principal Partner Shadowfax's Avatar
    Join Date
    Mar 2005
    Location
    Rock Hall, MD Home, New Hope, PA
    Posts
    412
    Ted,

    I don't propose that I'm any kind of weather expert, so this is just my read of the situation. I'm sure there is a closet weather man, if not a real one, on the list somewhere that can answerer our questions.

    It seems to me that the area where the highest winds are is a relativity small area compared to the total size of the storm and then the highest winds are found on an even smaller section of the north side of the eye wall. The farther away from the eye the lesser the winds and these storms are not really that large, maybe a couple to three hundred miles across before you lose the tropical winds designation, and moving 15 to 35 mph in a given heading. I don't know where the sea buoy in question is relative to the eye of the storm, but if it was one or two hundred miles away, this could account for the discrepancy. As we all know from sailing, the wind at the water surface is less then say 50 feet above the surface, this may also account for some of the difference, though I can't believe that much.

    I think the TV weather people all went to Cancun in hopes that they would witness another New Orleans and found that the eye of the storm was a couple of hundred miles away, so Cancun was only getting tropical storm winds, which is why I think they where not blown off the beach, but needed the drama to sell soap, so where quoting wind speeds found hundreds of miles away.

    Anyhow, that my read on it, flawed as it probably is.

    Paul Raywood
    s/v Shadowfax
    1988 E34 #257
    Rock Hall, Maryland, Home Port
    New Hope, Pennsylvania, Home

  5. #5
    Principal Partner
    Join Date
    Aug 2005
    Location
    Ellsworth, ME
    Posts
    769
    Well, the dropsondes are recording those super high wind speeds, so I'd believe them (I'm not sure NOAA has any reason to hype the hurricane).

    As for why the nav buoys don't match that recording? I don't know. Perhaps the wind exceeds the mechanical limits of those anemometers. I expect they might not be designed for the rare possibility that they would pass right through the eyewall of a cat 5 hurricane!

  6. #6
    Sustaining Partner
    Join Date
    Apr 2006
    Location
    Florida
    Posts
    212

    Wind Speeds

    It drives me to the point of not watching the news or the weather channel. They can't be happy reporting the facts but everything has to be so dramatic.

    In all of this hyped up, jacked up reporting from reporters on the scene, I noticed that in the background, the tiki huts were still standing, with their thatched roofs.

    One 'live' report from the Yucatan showed the damage to one poor family's house. There was a hole at one end of their thatched roof. Everything else was intact. It's hard to believe they experienced anything over about 50k with that minimal damage.



    In another live report, a van backed into the background. When asked about the van, the reporter said "oh, it's just another news service trying to get a satellite signal." Apparently there were several news services staying at that hotel. No doubt each had a crew of 5 or 10 plus equipment. They likely got rooms there because everyone else was required to evacuate. There's times you wish the winds were as high as reported.

    Capt Ron
    E-38 Kismet
    Auburndale, Florida
    Visit my web pages

  7. #7
    Contributing Partner
    Join Date
    Jun 2005
    Location
    Alameda CA
    Posts
    168

    Read #33

    Sorry, but they are giing you th facts...on a technical level. You afre looking at a hut still standing and saying they are lying??

    Anyway, read again NOAA #33 earlier in this thread. it freally tells the story. notice "aloft" and "at the surface, etc.

    Sorry I'm a little biased. I retired from all that wx business in 2000 after 43+ years.

  8. #8
    Principal Partner
    Join Date
    Dec 2004
    Location
    Annapolis, MD
    Posts
    1,294
    What is a dropsonde? What altitude is it recording windspeed at?

  9. #9
    Sustaining Member
    Join Date
    Nov 2003
    Location
    Hawthorn Woods Illinois
    Posts
    98

    From a meteorologist

    I posed the question asked here regarding the discrepancy between wind speeds being reported by TV weather guys and data we see on NOAA buoys to Tom Skilling, the WGN TV weather guru here in Chicago. Here is his explanation:

    Dear Gary,

    The handful of buoys available, wonderful and indispensible as they are as data collection devices for meteorologists, offer us only snapshots of weather often many miles and completely removed from the peak winds of a hurricane. A hurricane’s cloud shield can be deceptive, suggesting the storm’s wind field is larger than it actually is and that these winds somehow extend beyond their actual boundaries. The strongest winds of a hurricane are contained in a relatively compact “doughnut” of high winds surrounding the eye beneath the so-called eye wall. Unless this eyewall passes DIRECTLY over (or within 30-60 miles) of a NOAA buoy, the winds you see reported by the buoy will come nowhere near the peak wind speeds observed at the core of the storm.

    Hurricane hunter aircraft criss-cross hurricanes, often for 6-8 hours at a time, with onboard equipment which maps the wind field in detail and calculates its strength. Sensors on the aircraft and “dropsondes”---instrument payloads lauched from the aircraft which radio wind, temp, humidity and pressure info back to the plane as they descend to the oceans below----are the primary sources of wind information from hurricanes. There are also satellite borne sensors which induce and plot the storm’s wind field with great detail. In an area as large as the Caribbean, Gulf of Mexico and Atlantic, the chance one of the comparative handful of buoys will find itself in the core of the hurricane’s strongest winds, is more limited than you might think. That’s why the so-called “weather recon flights” and satellite observations are indispensable in understanding a given hurricane’s structure.

    Hope this helps! A great question---thanks for e-mailing us!



    Regards, Tom Skilling

  10. #10
    Contributing Partner Chris A.'s Avatar
    Join Date
    Oct 2005
    Location
    Portland, ME
    Posts
    125
    Cool post Gary- thanks for relaying that.
    Chris on Peregrine
    1987 E34 #247 Universal M25XP
    Portland, ME

  11. #11
    Senior Moderator Loren Beach's Avatar
    Join Date
    Dec 2000
    Location
    Portland, OR. Columbia River
    Posts
    7,743
    Blog Entries
    66

    Thumbs up

    Gary,
    My thanks, also.

    Loren

  12. #12
    Principal Partner
    Join Date
    Dec 2004
    Location
    Annapolis, MD
    Posts
    1,294
    Problem with the above analogy is that the eye of Dean passed with 1.7 NM of the buoy I was watching. I think the discrepany is due to wind readings being taken aloft and not at the surface. 150kt winds would pick up and toss small cars IMHO. I would like to know the altitudes at which these dropsondes are recording the 150kt wind speeds. It would not surprise me one bit to hear a hurricane had 150kt winds at several thousand feet, but I still want to see a surface recorded data point.

  13. #13
    Principal Partner
    Join Date
    Aug 2005
    Location
    Ellsworth, ME
    Posts
    769
    Quote Originally Posted by NOAA report above
    A PEAK FLIGHT-LEVEL WIND OF 165 KT WAS MEASURED JUST
    NORTH OF THE EYE. MAXIMUM SURFACE WINDS FROM THE SFMR WERE 124
    KT...BUT IT IS HIGHLY LIKELY THAT THE MAXIMUM SURFACE WIND SPEED
    WAS NOT REPORTED BY THE SFMR INSTRUMENT. A GPS DROPSONDE IN THE
    NORTHERN EYEWALL MEASURED A WIND SPEED OF 178 KT AVERAGED OVER THE
    LOWEST 150 METERS OF THE SOUNDING.
    This is saying that the average windspeed from 150 meters to 0 meters of altitude was 178 knots. The SFMR is a stepped frequency microwave radiometer carried aboard the Orion aircraft, and it (somehow) measures windspeeds at the surface. In this case 124 knots.

    It seems clear to me that the buoy report you're looking at is wrong. I can't say why it didn't give an accurate reading. But a number of other devices reported by NOAA showed wind speeds over 124 knots at the surface. I think it's much more likely that the buoy was wrong, and all the NHC-collected data is fairly accurate, don't you?

  14. #14
    Principal Partner
    Join Date
    Dec 2004
    Location
    Annapolis, MD
    Posts
    1,294
    Yes I agree it is likely that the buoy missed something. I have been trying for years to validate these other readings with actual buoy reports that were close enough during hurricanes nad not had any luck. Mostly done while watching them come up the chesapeake. ie Isabelle. Would 165kt winds not pick up and throw small cars though?

  15. #15
    Principal Partner Shadowfax's Avatar
    Join Date
    Mar 2005
    Location
    Rock Hall, MD Home, New Hope, PA
    Posts
    412
    Would 165kt winds not pick up and throw small cars though?[/QUOTE]

    Yes that is very close to what a tornado does, though a tornado 's winds are more circular, whereas a hurricane's winds tend to be more strait line.

    Paul Raywood
    s/v Shadowfax
    1988 E34 #257
    Rock Hall, Maryland, Home Port
    New Hope, Pennsylvania, Home

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •