It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Some features of ATS will be disabled while you continue to use an ad-blocker.
Category 3 will be 111-129 mph; it used to be 111-130.
Category 4 will be 130-156 mph; it used to be 131 to 155.
Category 5 will be 157 mph and higher. It used to be 156 and higher.
Category 1 and 2 systems will remain unchanged.
The new numbers will be used as of May 15.
"The change is a minor math thing between the knots and mph," said Dennis Feltgen, hurricane center spokesman. "It has no other impact on the scale."
Maybe it's a misprint, but how much would you bet that if there is a hurricane with 130mph winds that they'll say it's a Cat 3 instead of a Cat 4?
Normally, the National Hurricane Center computes storm strength in knots, widely used by boaters and pilots but not the general public.
To more accurately convert knots to miles per hour:
Hurricane - Category 3: Winds of 96 to 113 knots. Storm surge 9 to 12 feet above normal.
The National Hurricane Center (NHC) and Central Pacific Hurricane (CPHC) assign intensities of hurricanes in 5-knot (kt) increments. For advisory products, these intensities are converted to miles per hour (mph) and kilometers per hour (km/h), and then rounded to the nearest 5-mph or 5-km/h increments. Challenges occur when the current Category 4 intensity is 115 kt (132.3 mph). Although 115 kt is within the Category 4 range, the equivalent rounded wind speed in mph is 130 mph, which is in the Category 3 range. To classify the hurricane as a Category 4 in both sets of units (kt and mph), NHC and CPHC must incorrectly convert 115 kt to 135 mph in the advisory products. A similar issue occurs when the current Category 4 intensity of 135 kt is converted to km/h.