RANT: Storm Classification, Media Hype

After re-reading my own blog entry on the lameness of Tropical Storm Beryl, I feel I must rant. I don't rant often on my blog. In fact this is probably the first time. I've created this little header to warn you of future rants, so you're not caught off-guard:

This is something I've always said: The strength and potential damage from Tropical Storms (and Hurricanes) are often over-hyped by the media, including AccuWeather and the National Weather Service.

This is done, of course, because it's better safe than sorry, especially when a recent study showed that 1/4 of the people will ignore the warnings anyway. So I'm neither making excuses nor saying that it shouldn't be done. But you, the Netizens, need to be aware of this.

I've watched many a tropical system come on shore since the Internet era allowed for real-time observation. Almost never can you find an observation that is even close to the supposed strength of the storm. I don't have time right now to do the research to give you specific numbers, but here are a few examples. Fran in 1996 was supposedly a 113 knot storm, but the best surface ob was 79 knots sustained, and that was with instrumentation 50 feet above the standard height. Take Charley in 2004, supposedly 130 knots and landfall, but 78 was the highest recorded. Both Jeanne and Ivan in 2004 were supposedly 105-knot storms but neither could achieve above 79 knots. All data was obtained from NHC histories.

Why is this?

SPARSENESS OF OBSERVATION STATIONS: The first thing you'll probably say is "Well Duh, how far apart are the (working) weather stations?" NHC has admitted this is a problem before (see their "Charlie" analysis where they say "As usual, there were no official surface anemometer measurements of wind speeds even approaching the intensity estimate near the landfall location.") The problem is aggravated by stations that are knocked out by the storm (and they admit "failures remain a chronic problem in landfalling hurricanes.") And then there are the stations that weren't working in the first place (as happened with Beryl). I will admit that these are part of the problem in documenting storm strength, but they have become less problematic since the advent of amateur and private weather station networks in the 2002-2004 period. For example, I count at least 60 stations southeast of Boston that were in the path of Beryl. And there are places (mostly on the Southeast and Gulf coasts) where there are no weather stations. But that doesn't explain that time and time again, we can't find observations worthy of the supposed strength of the storm.

RECON INACCURACY: I don't want to bust on the Hurricane Recon Guys because you don't see me flying into a storm. But I just can't believe in the formulas (and manual finagling) that the NHC uses to compute surface winds from them. Although they occasionally take other observational data into account, it seems like recon data is what they use most of the time to assign a storm a Saffir-Simpson classification. If you think of how small a plane's path is compared to a hurricane, and how complex of a weather system it is on a mesoscale level, it just doesn't make sense. Someone else who doesn't believe the recon hype is Joe Bastardi, who issued this diatribe which includes a new way for calculating the Saffir-Simpson scale of a hurricane based on recon data. During Beryl it caused his estimate of winds to be both above, and below, the NHC fixes.

STORM STRUCTURE: People say that the worst part of a storm (in the western Atlantic) is generally the RFQ (Right-Front Quadrant, when looking in the direction the storm is moving). The theory is that you add the forward motion of the storm to the sustained wind speed in that area (in the Left Front Quadrant the wind is going opposite of the forward motion and in the Lower Front Quadrant the winds don't have the "fetch"). This is obviously more pronounced for hurricanes which are moving faster. Although this is what I was taught in college, meteorologists argue about whether the RFQ really makes a lot of difference in the overall wind speeds. The winds certainly seemed to be stronger in the RFQ for Beryl, as analyzed by RadarPlus (which uses the WRF model analysis).

ALSO IN THIS CORNER... There's one thing for sure about the RFQ: Damage is much worse because the winds are coming onshore in the RFQ, assuming a perpendicular hit, causing great storm surge. For a storm moving westward onto the East Coast, this perpendicular problem is not always encountered directly (because it depends on the angle of the storm and the coastline). There are a couple of important exceptions, one being the south-facing beaches of Brunswick County, North Carolina, which I have blogged about before (see illustration at right). Compare the light Bertha damage (talked about below) to the heavy Hugo damage detailed in this blog entry, and remember Oak Island's location: HUGO - 150 MILES AWAY (IN THE RFQ), BERTHA 20 MILES AWAY (NON-RFQ). Imagine the damage Hugo would have caused had it hit as close as Bertha.

FRICTION, BABY! As soon as the outer edge of a hurricane or tropical storm encounters the coastline, friction starts to disrupt the high winds. It would seem reasonable then, that any approaching high winds would get lowered at the coastline and the highest gusts would never make it to the coastline, let alone past there. If your weather station was not on the coastline, sticking out into the RFQ (see above), you'd never get those maximum winds.

A WORD ABOUT THE LACK OF DAMAGE AT COASTAL AREAS: When I visited Oak Island, NC after Hurricane Bertha, I was amazed at the lack of damage. A Category 2 hurricane had struck just 20 miles away yet only a few shingles were lost; an occasional light pole was down. You can see the photos I took here, and that's after driving around the island trying to find damage photos, and the telephone pole shot was "first row" I think. Sure there's some minor damage, but the houses and trees are, for the most part, still standing.

It's important to remember that coastal vegetation and houses are built to withstand hurricanes, especially if the humans there have taken adequate preparations such as boarding up windows and the area is NOT in the RFQ (see above). The trees and scrub bushes on Oak Island constantly battle wind from the shore, so they aren't going to be knocked down by a 75, or probably even 100 mph wind. I even considered staying on the island to meet Bertha or Fran in 1996, because it would take a Cat 5 storm to really inundate or blow away everything on the island. (I decided not to based on the fact that the stranding of me on the island for days afterward without food, water or sunblock would do more damage to me than the storm).

Am I crazy here or are you with me? Send me an email and let me know. Maybe I'm just talking out my blowhole and I've been out of meteorological school too long. If I've missed something scientific, I apologize.

*See "Beryl Wrapup: A Quiet, Lame Storm". AP PHOTO: Kyla Koumarianos, 1, hands her mom a shell she found on Chatham Beach near Chatham Light in Chatham, Mass., Thursday,, July 20, 2006. A tropical storm warning flag flies above them as tropical storm Beryl is expected to pass by the area sometime on Friday. (AP Photo/Stephan Savoia)

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