It should be documented as a cat 4 based on the officially analyzed maximum sustained winds in the last NHC advisory just before landfall. I believe that is how they are rated regardless of any actual measured surface winds on land. There has been much discussion today on various groups as to what goes on with overland wind speeds in landfalling hurricanes.
Check these articles:
Hurricane Winds at Landfall: A Measurement Challenge
For a variety of reasons, land-based observations seldom live up to a hurricane’s Saffir-Simpson ranking at landfall.
www.wunderground.com
Just now had a chance to read the first article. I find this subject quite interesting and always wondered why we never seem to get land observations that confirm the NHC forecast.
I’m not sure what to make of this quote from the first article:
“(Josh) Wurman’s sense is that few if any people—even right on the coast—will experience sustained winds on par with the NHC ratings for a landfalling hurricane. “Even if the open ocean values are correct, they are extremely non-representative,” he added. Wurman uses this rough analog: if a midlatitude winter storm producing 120-mph winds atop Mount Washington were heading toward Boston, the local forecast probably won’t leave Bostonians thinking they might experience the same wind. “NHC should make clear what scientists and engineers know is true—that max gusts over land will be near or below their open-ocean sustained-wind estimates.” “
The analogy implies that it’s an issue of height where the wind speed is measured. But my understanding is that NHC accounts for that, don’t they apply mathematical formulas to derive surface winds from higher-level flight readings and satellite measurements?
The concluding quote from Marty Bell seems to contradict Wurman anyway:
“When the over-water storm estimate and inland observing environments are reconciled, we find that the differences are not as great as they initially appear. This has important ramifications [for] public safety, the insurance industry and others since there is a widely-held belief that the NHC often over-estimates storm intensity by a category or more.”
I guess the “reconciliation” involves accounting for friction over land, but if so then shouldn’t this effect be made part of NHC’s wind speed estimates for forecasting purposes?
So I’m left without much clarity, except to realize that it remains a mystery at best, perhaps it can even be called a controversy?
