Wilma on verge of Category 5 after historic pressure drop

Hurricane Wilma’s explosive intensification has continued in a very big way — dropping 69 millibars in 8 hours!!! — and she is now a Category 4 major hurricane with winds of 150 mph. According to the discussion:

AN AIR FORCE PLANE JUST MEASURED 162 KNOTS AT 850 MB AND A MINIMUM PRESSURE OF 901 MB IN A PINHOLE EYE. WILMA IS NOW A VERY STRONG CATEGORY FOUR HURRICANE AND COULD BECOME A CATEGORY FIVE TODAY.

That pressure of 901 millibars is ridiculously low — a millibar lower than Katrina’s lowest pressure, and just four millibars higher than Rita’s lowest pressure. Wilma is now the fifth most intense hurricane ever recorded in the Atlantic basin. Three of the six most intense Atlantic basin hurricanes in recorded history have occurred this year.

Given the incredibly low pressure, it seems almost certain that Wilma’s winds will “spin up” to Category Five strength over the next 6-12 hours.

Bryan Woods at The Storm Track writes: “I thought I had seen everything this hurricane season, but I was wrong. WOW! … Between 5pm EDT and 1pm EDT Wilma’s pressure dropped from 970 mb to 901 mb and her winds increased from 80 mph to 150 mph. This rate of strengthening in incredible. A strengthening of 69 mb in 8 hours is absolutely amazing.”

To give you some perspective: a drop of one millibar per hour is considered “rapid intensification.” Wilma has been averaging more than 8 millibars per hour!

He adds: “Wilma clearly has her sights set on passing through the Yucatan Gap and heading directly at Southern Florida. This is no longer a joking matter. We have yet another catastrophic hurricane at hand.”

I’m not sure it ever was a joking matter, but it certainly isn’t now.

P.S. This earlier post from Woods shows that the oceanic heat content diminishes north of the Florida Keys — so if Wilma follows the expected track, she’s unlikely to make landfall as a Cat. 5. But that’s no reason to rest easy. It doesn’t take a Cat. 5 to cause serious devastation. Witness the destroyed Mississippi coastline, where Katrina came ashore as a Category 3 or maybe even a strong Cat. 2!

Get ready, south Florida. Wilma’s big, she’s bad, and she’s coming.

P.P.S. Here’s the latest recon data. Look at line “F” for the maximum flight-level wind and line “H” for the minimum central pressure. At present, the most recent report (162 kt, 901 mb) is as of 04:32:40Z (see line “A”).

And here’s a look at the computer models.

3 Responses to “Wilma on verge of Category 5 after historic pressure drop”

  1. Chris James says:

    If Wilma makes Cat5, that would make THREE cat 5’s in one year, a record, and all within a two month timeframe.

    I’ve noticed that forcast tracks tend to “bend right”, so maybe, just maybe, Wilma will transit the Florida Straits instead of hitting S Florida directly. That’s about the best hope I can see.

  2. Brendan says:

    Just happened… thanks for the reminder, I will note that in my new post.

  3. […] The Atlantic has seen speedier bursts of intensification in recent years — Hurricane Wilma’s 8-hour, 69-millibar plunge in 2005 comes to mind — but still, going from a T.D. to a Cat. 5 in less than 48 hours is quite a […]