Did Hurricane Wilma have 209 mph sustained winds?
At last week's 30th Conference on Hurricanes and Tropical Meteorology of the American Meteorological Society, Dr. Eric Uhlhorn of NOAA's Hurricane Research Division presented a poster that looked at the relationship between surface winds measured by the SFMR instrument and flight-level winds in two Category 5 storms. Hurricane Hunter flights done into Category 5 Supertyphoon Megi (17 October 2010) and Category 5 Hurricane Felix (03 September 2007) found that the surface winds measured by SFMR were greater than those measured at flight level (10,000 feet.) Usually, surface winds in a hurricane are 10 - 15% less than at 10,000 feet, but he showed that in super-intense Category 5 storms with small eyes, the dynamics of these situations may generate surface winds that are as strong or stronger than those found at 10,000 feet. He extrapolated this statistical relationship (using the inertial stability measured at flight level) to Hurricane Wilma of 2005, which was the strongest hurricane on record (882 mb), but was not observed by the SFMR. He estimated that the maximum wind averaged around the eyewall in Wilma at peak intensity could have been 209 mph, plus or minus 20 mph--so conceivably as high as 229 mph, with gusts to 270 mph. Yowza. That's well in excess of the 200 mph minimum wind speed a top end EF-5 tornado has. The Joplin, Missouri EF-5 tornado of May 22, 2011 had winds estimated at 225 - 250 mph. That tornado ripped pavement from the ground, leveled buildings to the concrete slabs they were built on, and killed 161 people. It's not a pretty thought to consider what Wilma would have done to Cancun, Key West, or Fort Myers had the hurricane hit with sustained winds of what the Joplin tornado had.
Figure 1. Hurricane Wilma's pinhole eye as seen at 8:22 a.m. CDT Wednesday, Oct. 19, 2005, by the crew aboard NASA's international space station as the complex flew 222 miles above the storm. At the time, Wilma was the strongest Atlantic hurricane in history, with a central pressure of 882 mb and sustained surface winds estimated at 185 mph. The storm was located in the Caribbean Sea, 340 miles southeast of Cozumel, Mexico. Image source: NASA's Space Photo Gallery.
Figure 2. Damage in Joplin, Missouri after the EF-5 tornado of May 22, 2011. Image credit: wunderphotographer thebige.
Official all-time strongest winds in an Atlantic hurricane: 190 mph
The official record for strongest winds in an Atlantic hurricane is 190 mph, for Hurricane Allen of 1980 as it was entering the Gulf of Mexico, and for Hurricane Camille of 1969, as it was making landfall in Pass Christian, Mississippi. In Dr. Bob Sheets' and Jack Williams' book, Hurricane Watch, they recount the Hurricane Hunters flight into Camile as the hurricane reached peak intensity: On Sunday afternoon, August 17, and Air Force C-130 piloted by Marvin Little penetrated Camille's eye and measured a pressure of 26.62 inches of mercury. "Just as we were nearing the eyewall cloud we suddenly broke into a clear area and could see the sea surface below," the copilot, Robert Lee Clark, wrote in 1982. "What a sight! Although everyone on the crew was experienced except me, no one had seen the wind whip the sea like that before...Instead of the green and white splotches normally found in a storm, the sea surface was in deep furrows running along the wind direction....The velocity was beyond the descriptions used in our training and far beyond anything we had ever seen." So, the 190 mph winds of Camille were an estimate that was off the scale from anything that had ever been observed in the past. The books that the Hurricane Hunters carried, filled with photos of the sea state at various wind speeds, only goes up to 150 mph (Figure 2). I still used this book to estimate surface winds when I flew with the Hurricane Hunters in the late 1980s, and the books are still carried on the planes today. In the two Category 5 hurricanes I flew into, Hugo and Gilbert, I never observed the furrowing effect referred to above. Gilbert had surface winds estimated at 175 mph based on what we measured at flight level, so I believe the 190 mph wind estimate in Camille may be reasonable.
Figure 3. Appearance of the sea surface in winds of 130 knots (150 mph). Image credit: Wind Estimations from Aerial Observations of Sea Conditions (1954), by Charlie Neumann.
Figure 4. Radar image of Hurricane Camille taken at 22:15 UTC August 17, 1969, a few hours before landfall in Mississippi. At the time, Camille had the highest sustained winds of any Atlantic hurricane in history--190 mph.
The infamous hurricane hunter flight into Wilma during its rapid intensification
While I was at last week's conference, I had a conversation with Rich Henning, a flight meteorologist for NOAA's Hurricane Hunters, who served for many years as a Air Reconnaissance Weather Officer (ARWO) for the Air Force Hurricane Hunters. Rich told me the story of the Air Force Hurricane Hunter mission into Hurricane Wilma in the early morning hours of October 19, 2005, as Wilma entered its explosive deepening phase. The previous airplane, which had departed Category 1 Wilma six hours previously, flew through Wilma at an altitude of 5,000 feet. They measured a central pressure of 954 mb when they departed the eye at 23:10 UTC. The crew of the new plane assumed that the hurricane, though intensifying, was probably not a major hurricane, and decided that they would also go in at 5,000 feet. Winds outside the eyewall were less than hurricane force, so this seemed like a reasonable assumption. Once the airplane hit the eyewall, they realized their mistake. Flight level winds quickly rose to 186 mph, far in excess of Category 5 strength, and severe turbulence rocked the aircraft. The aircraft was keeping a constant pressure altitude to maintain their height above the ocean during the penetration, but the area of low pressure at Wilma's center was so intense that the airplane descended at over 1,000 feet per minute during the penetration in order to maintain a constant pressure altitude. By they time they punched into the incredibly tiny 4-mile wide eye, which had a central pressure of just 901 mb at 04:32 UTC, the plane was at a dangerously low altitude of 1,500 feet--not a good idea in a Category 5 hurricane. The pilot ordered an immediate climb, and the plane exited the other side of Wilma's eyewall at an altitude of 10,000 feet. They maintained this altitude for the remainder of the flight. During their next pass through the eye at 06:11 UTC, the diameter of the eye had shrunk to an incredibly tiny two miles--the smallest hurricane eye ever measured. During their third and final pass through the eye at 0801 UTC, a dropsonde found a central pressure of 882 mb--the lowest pressure ever observed in an Atlantic hurricane. In the span of just 24 hours, Wilma had intensified from a 70 mph tropical storm to a 175 mph category 5 hurricane--an unprecedented event for an Atlantic hurricane. Since the pressure was still falling, it is likely that Wilma became even stronger after the mission departed.
I'll have a new post by Tuesday at the latest.
Jeff Masters
Reader Comments
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Hey, gamma. Looks like were are getting our old Spring rains back. We have overflows on our pool but the rain came down really heavy and it went over the top. I haven't seen that in years. I think they will have to cancel the Air Show today on the beach.
What...so we have Invest 92-L?!
However, while we are sometimes overly snappish about newbies, we are mostly pretty decent to pple coming in to ask questions or to bring info from their local area. We're mostly glad to have new blood, if it's not troll blood.... lol
And no, we don't drink blood....
Hi neighbor, they did cancel the Air Show for today.
we have overflow on our pool also but the ground is saturated and it came down so fast.
have not seen Spring rain like this in years.
the Euro/Nogaps/CMC has been showing this energy moving into the GOM..
Nogaps
CMC
I still don't see signs of the mid-upper trough dropping the surface pressures for tropical cyclone formation. I just checked and all surface pressures have been steady and are around 1017 mb in S FL. Winds are stiff in the easterly direction...so no signs of a surface spin at this time.
When is the last time we saw something like this?
OK, you all know the drill. If you want to see this image animated, shake your PC's or rock back and forth in your chair.
I see it too! I am watching to see if surface wind directions begin to respond. Back with Invest 90-L in February one could see multiple spins on Miami radar...but they were all mid-level and not at the surface.
Already 2.02 inches in Nassau this morning. It is getting annoying... I wanna go to the beach and play tennis, man. -_-
Nassau Weather Station
I really wouldn't be wishing for a hurricane at any time in Tampa. There's a lot more of Tampa to flood than there was the last time it got a direct hit.
It's only off by about 100 miles to the west compared to the 10 day forecast...10 days ago.
It sure is.
Isn't it hard running in the sand?
Just thought I would share.
The MDR should warm steadily as the NAO seems to be going negative
Good morning Nigel...did you see the disturbance in the Florida Straits?!
I messed up early this morning by calling it off for tropical development. Now I am planning to write a special update shortly to "eat some of my words."
Does anyone know if this is Invest 92-L? Someone had referred it to as an "invested trough" but I don't see it on the Navy NRL site...
But we shall see.
Link
very nice, especially the 4th one with the lightning
Yes i did...is it being watched for tropical developement
Those rain gauges don't always mean anything. A few years ago, Northeast Broward got over 8" of rain in a few hours and the rain gauge at the airport reported just over an inch. Some of these systems can drop heavy rain over very small areas and the gauges do not always get them. I have an 11" double cylinder rain gauge. It has over 5" now. (Of course my funnel is 4 feet wide.)
April 28, 2012
What's up Baha...how's the rain over there?
But who know's how long THAT'll last..... lol
April 28, 2012
You are so right.
Actually we are way behind on rain because of last year being so dry.
I really do hope we get some good soaking rains.
Around here there are Pecan and Pulp tree plantations that suffered so much.
Pecans were like gold.
I say let it rain {but not from any hurricaine Ivan please}
NATIONAL WEATHER SERVICE MIAMI FL
1021 AM EDT SUN APR 29 2012
.UPDATE...FORECAST OVER THE NEXT 24 HOURS JUST GETS MORE
CHALLENGING WITH MODEL CONSENSUS STILL NOT COMING INTO PLAY. THE
NAM AND GFS ARE NOW THE MOST AGGRESSIVE WITH WIND FIELDS AND
RAINFALL WHEREAS OVER THE PAST COUPLE OF DAYS IT HAD BEEN THE
ECMWF WITH THE NAM BEING AN OUTLIER. CONSIDERING THE RAIN IS
CURRENTLY ONGOING, CERTAINLY DO NOT PLAN TO CHANGE THAT PART OF
THE FORECAST AND WITH THE EASTERLY FLOW THIS FEED OF MOISTURE WILL
CONTINUE THROUGHOUT THE DAY. THIS ALSO IS INDICATIVE FROM THE WATER
VAPOR IMAGERY WHICH CLEARLY SHOWS A DEEP TROPICAL MOISTURE PLUME
EXTENDING NORTH FROM THE CARIBBEAN ON THE WEST SIDE OF A
SIGNIFICANT MID LEVEL TROUGH. THERE ALSO HAVE BEEN BANDS OF
EMBEDDED HEAVY SHRA MOVING ONSHORE OF THE SE CST SOUTH OF PALM
BEACH COUNTY. THERE HAS NOT BEEN ANY TRAINING OF ECHOS SETTING UP
THIS MORNING PER SE ALONG THE E CST BUT THE CONTINUATION OF THE
FEED OF MOISTURE STILL LIKELY WILL LEAD TO IMPRESSIVE RAINFALL
AMOUNTS OVER THE NEXT 24 TO 36 HOURS SO THE FLOOD WATCH WILL
REMAIN IN PLACE.
FOR THE WIND FIELDS, THESE HAVE BEEN VERIFYING OVER THE
ATLANTIC WATERS AND WHILE THERE IS NO INDICATION AS OF 14Z THAT A
SFC LOW HAS DEVELOPED OVER THE FL KEYS BOTH THE NAM AND GFS SHOW
THIS TO MATERIALIZE BY EARLY THIS AFTERNOON. AND WHILE THIS MAY OR
MAY NOT OCCUR, THE PRESSURE GRADIENT HAS BEEN ON THE INCREASE SO
WILL LEAVE THE SCA TO BEGIN OVER THE GULF WATERS AT 18Z.
Rain gauges are like real estate, location, location, location.
I expect we'll get some more rain this afternoon.
nic low overe ND
that is right, the airport probably reports the lowest rain fall in the entire county...
To me this should at least be tagged 92L
surface trough right now looks to have a low forming on it
OK,it's now clearing out in the central Caribbean
AND WHILE THERE IS NO INDICATION AS OF 14Z THAT A
SFC LOW HAS DEVELOPED OVER THE FL KEYS BOTH THE NAM AND GFS SHOW
THIS TO MATERIALIZE BY EARLY THIS AFTERNOON
Hmmmmm.... Surface low to form?
last few frames of the visible to me indicate one starting to form
Viewing: 751 - 801
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