I'm waiting to see if this is really true. From what I"ve been reading NOAA is overestimating these things by the way they've changed measuring them from the way they used to. They now use airplane-based radar and drop sondes that rely on GPS to calculate wind speed. A GPS engineer commented that that small size of GPS unit would be subject to a lot of error due to turbulence and other things. Historically, hurricane strength (wind speed) was measured 10 meters above ground by anemometers, not thousands of feet in the air where wind speeds are higher using indirect methods.
Very true!
 
For example, here is a graph of when hurricane Maria passed over buoy 42060, which is a little less than half way between Dominca and Puerto Rico. Notice how the pressure drops dramatically then increases and the wind speed increases then decreases as the eye passes over. The max wind speed was about 80 knots (about 92 mph), which is only a cat 1 hurricane on the Saffir-Simpson scale.

plot_wind_pres.php


http://www.ndbc.noaa.gov/plot_wind_pres.php?station=42060&uom=E&time_diff=-4&time_label=AST
 
For example, here is a graph of when hurricane Maria passed over buoy 42060, which is a little less than half way between Dominca and Puerto Rico. Notice how the pressure drops dramatically then increases and the wind speed increases then decreases as the eye passes over. The max wind speed was about 80 knots (about 92 mph), which is only a cat 1 hurricane on the Saffir-Simpson scale.

plot_wind_pres.php


http://www.ndbc.noaa.gov/plot_wind_pres.php?station=42060&uom=E&time_diff=-4&time_label=AST

What part of the storm was sampled? When the planes do their runs, they report where in the storm the highest wind speeds were recorded. The northeast quadrant is typically the worst. On a northwest course, with the eye passing over the buoy, I would think the nortwest and southeast parts of the storm were the ones that passed over the buoy.

But of course, an airplane can't realistically sample wind speeds at ground level, where even things like waves will create a certain amount of turbulence and drag. The anemometer on buoy 42060 is only 4 meters above the water. (Supposedly, the Hurricane Hunter doing a recent sampling got a flight-level (about 10,000 ft) reading of 180 mph . . . just how to extrapolate that to surface-level winds is hotly debated.)
 
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What part of the storm was sampled? When the planes do their runs, they report where in the storm the highest wind speeds were recorded. The northeast quadrant is typically the worst. On a northwest course, with the eye passing over the buoy, I would think the nortwest and southeast parts of the storm were the ones that passed over the buoy.

But of course, an airplane can't realistically sample wind speeds at ground level, where even things like waves will create a certain amount of turbulence and drag. The anemometer on bouy 42060 is only 4 meters above the water.

They'll fly a couple of different directions through a hurricane, typically centered out from the eye, so they can get pressure, wind speed, temp etc from a number of different locations in the storm. I read this morning that Maria was actually so disorganized yesterday morning that they couldn't find her center of circulation, and had to hunt for it. Once they did, they did their flight path and found her to be a Cat 3 level, hense the sudden jump.

Obviously, these are examples... Not sure what storms these pics are from.
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