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
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 — Blog Index
What's up gamma...are you enjoying your weekend?
I know. I guess you saw the pictures I put here earlier and loaded 3 on my blog.
may need that rubber boat I have in backyard. LOL
yes they did.. made national news....
they got that much in 24 hours.. so far I've only got close to 6" in 24 hours..
We're also expecting above average rains over the next 7 days,with as much as 4-6 inches in some areas in Trinidad
You put Grothar on your list and not me? That's it, I'm retiring my Intellicast images!
I remembered it too, although I was in Melbourne at the time, but long time in South Florida.
What's up DDR? It's now clearing up in the central Caribbean after a period of wet and cloudy conditions
my veggie and herbs are a mess anyway, I have not tended them in months.. as you can see they have gone to seed and been overtaken by weeds...
soon I have to go out there and clean that mess up!
this flood should finish them off!
Excerpt:
AN UPPER LEVEL TROUGH EXTENDS OVER THE FAR WRN ATLC IS
SUPPORTING A MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION CENTERED
IN THE STRAITS OF FLORIDA NEAR 24N80W. WHILE MOST OF THE HEAVY
CONVECTION IS CURRENTLY OVER THE WRN ATLC AND THE FLORIDA
PENINSULA...DOPPLER RADAR IMAGERY INDICATES SOME SCATTERED
SHOWERS ENTERING THE EXTREME ERN GULF THROUGH THE S-WRN TIP
COAST OF THE FLORIDA PENINSULA AND THE FLORIDA KEYS. THE
REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF MOSTLY DRY AIR
AND SUBSIDENCE ALOFT AND SURFACE RIDGING ACROSS THE AREA. MARINE
OBSERVATIONS SHOW ESE WINDS IN THE RANGE OF 10 TO 20 KT...
INCREASING TO UP TO 25 KT NEAR THE COAST OF TEXAS. COMPUTER
MODELS SUGGESTS THAT ENERGY ASSOCIATED WITH THE UPPER LEVEL
TROUGHING WILL SLIDE WESTWARD ACROSS THE S-CENTRAL GULF.
ALTHOUGH MOST MODELS SUGGEST A SURFACE TROUGH MOVING ACROSS THE
S-CENTRAL GULF...THE GFS MODEL REMAINS THE MOST AGGRESSIVE IN
DEVELOPING A WEAK SURFACE LOW ACROSS WESTERN CUBA ON THE
SOUTHWESTERN PERIPHERY OF THE RIDGE THAT EVENTUALLY WEAKENS AND
DISSIPATES ACROSS THE NW GULF WATERS.
thanks much nrt
It was rather nice and unexpected, considering we supposedly had about a 10 to 20% chance of an isolated shower with no real accumulation expected lol. It seemed coverage was closer to 30 or 40% yesterday, localized places in Central Florida along the west coast got over an inch.
It will be interesting to see what happens the next few days considering yesterday we had more than expected. The problem is, although mean PWAT is only 1.25 today like yesterday, low level moisture can pool and build along sea breezes allowing deeper tropical moisture to get between 1.75 to 2 inches along the boundary.... I've seen before where only an isolated shower is supposed to pop but we end up getting decent thunderstorm buildup on the sea breeze. I'm not saying it happens all the time but I've seen it happen pretty often.
That being said it will be interesting to see if the forecast for us in Central Florida during the next week ends up being a bit of a dry bias. We shall see...
Sometimes the low level atmosphere can do things that the computer models don't see at all, and the low level atmosphere is a very important factor in Florida weather. That is much of why its hard to predict weather here.
As for South Florida, looks like the wet season is already getting started, which is normal. It typically begins in May for South Florida and takes a few weeks longer for us up here in Central Florida. Well, not always, but that is what is typical.
136 PM EDT SUN APR 29 2012
.NOW...THE AXIS OF THE INVERTED SURFACE TROUGH ACROSS THE BAHAMAS AND SOUTH FLORIDA IS SLOWLY MOVING WESTWARDS THIS AFTERNOON...KEEPING THE STEADY MODERATE TO HEAVY RAIN ACROSS FAR SOUTHERN FLORIDA AND THE KEYS.
SEVERAL CONVERGENT SHOWER BANDS HAVE DEVELOPED OVER THE LOCAL ATLANTIC ON THE NORTH SIDE OF THE TROUGH...AND THESE WILL CONTINUE TO MOVE INTO THE COAST SOUTH OF CAPE CANAVERAL THROUGH THE EARLY EVENING HOURS. BRISK EAST-NORTHEAST FLOW AROUND 15 TO 20 MPH WILL MEAN THAT THESE SHOWERS WILL BE ABLE TO HOLD TOGETHER LONG ENOUGH TO REACH INTO OKEECHOBEE AND SOUTHERN OSCEOLA COUNTIES. ADDITIONAL SHOWER AND POSSIBLY THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE...MAINLY OVER OKEECHOBEE AND OSCEOLA COUNTIES WHERE CLOUD COVER IS THINNER AND DAYTIME HEATING HAS BEEN BETTER.
BRIEF HEAVY DOWNPOURS ARE POSSIBLE WITH ANY ACTIVITY...AND OCCASIONAL LIGHTNING STRIKES WITH ANY THUNDERSTORM DEVELOPMENT.
&&
I wonder how long it has to potentially become one.
So all that moisture is headed to the upper Texas coast?
lol a few years back we had 15 inches in 4 hours here in Central and also South Pinellas. I don't know if you remember that but it was crazy, you could even small salt water in the air.
This shear map shows 45 kts of shear, not 20, besides your map showed 30 not 20.
LinkMelbourneRadar
LOL...So sorry Geoff...I was "lost in the moment" ..
Who could forget you?!?
Yeah it really is, I've seen a lot of crazy intense rain storms over the years living here, but that was one of the worst. The lightning was really intense and continuous as well, impressive wind gusts also.
What's up hydrus?
An early look at the SAL
IMO...if one goes strictly on how the models evolve the 200 mb upper-level winds...it only has today to do so (paragraph 4 of this discussion). However in that same paragraph...I noted the computer models haven't handled the upper wind evolution that well either....
So I am waiting for the surface obs in S FL to respond. If the wind directions/pressure measurements show a surface spin developing...then yeah we've got tropical cyclone formation. Otherwise we don't.
Not so sure...if the surface trough lives long enough to make it there...the upper trough that spawned it will have been long gone. The upper trough is crucial in creating upper divergence/lift for rainfall along the surface trough. By the time the surface trough makes it to Texas (if it does)...there will be a lot of shear and no upper divergence to help make it rain.
A non factor at the present time.
Thanks much Geo
Anyone else see the cirrculation?
NWS NATIONAL HURRICANE CENTER MIAMI FL
245 PM EDT SUN APR 29 2012
MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.
GULF OF MEXICO...
THERE IS STILL A CONSIDERABLE AMOUNT OF UNCERTAINTY IN THE
DETAILS OF THE EVOLUTION OF THE MID LEVEL LOW CURRENTLY NEAR THE
FLORIDA KEYS. SURFACE OBSERVATIONS REMAIN EASTERLY ON BOTH SIDE
OF THE FLORIDA STRAITS...WITH NO HINT OF A SURFACE LOW
DEVELOPING AT THIS TIME. THE ASCAT PASS FROM 1550 UTC SHOWED
E-NE WINDS TO 20 KT OFF THE COAST OF NAPLES FLORIDA...WELL N OF
FLORIDA BAY. THE 12Z GFS CARRIES 25 KT N-NE WINDS S OF NAPLES AT
1800 UTC TODAY. OBSERVATIONS DO NOT SUPPORT THESE WINDS WHICH
APPEARS TO BE A BI-PRODUCT OF CONTINUED CONVECTIVE FEEDBACK
ISSUES WITH THE GFS. HOWEVER...THE OBSERVATIONS THIS MORNING AND
AFTERNOON FAVOR A STRONGER SOLUTION THAN THE PREVIOUS PACKAGE.
ADJUSTMENTS WERE MADE TOWARD THE UKMET SOLUTION WHICH BRINGS THE
SYSTEM WESTWARD INTO THE GULF MORE SLOWLY THAN THE GFS AND WAITS
TO INCREASE WINDS TO 25 KT UNTIL LATE MON. THE TREND IN THE
MODELS HAS BEEN TOWARD MAINTAINING STRONGER RIDGING ALONG THE
NORTHERN GULF COASTAL PLAIN AND SOUTHERN PORTION OF THE CENTRAL
GULF COAST STATES...MAKING FOR A STRONGER PRES GRADIENT BETWEEN
THE SURFACE REFLECTION OF THIS SYSTEM AND THE RIDGE. THE 12Z
UKMET IS CONSISTENT WITH ITS 00Z RUN IN ENDING THE 20 KT WINDS
AND SEAS AT OR OVER 8 FT IN THE NE GULF AFTER 1800 UTC WED.
Something is changing.
New low forming?
Becoming more elongated?
That was something. There were places that got more than 16 inches though. I remember waking up during the night and I don't think I have ever seen rain like that before. In a two hour period it was like 7 inches. State Rd 84 was under water and we could not go from Dade to Broward County. The cows in Davie were up to their neck for days and many had to be put away. Our backyard had 10 feet of water and the front was covered right up to the door (about 4 feet).
Miami airport was under a couple feet of water. I have not seen anything like it since. With the exception of one in October in the early 90's. I don't remember the year.
BINGO! I see a very tight swirl just emerging just W of 20W...and just S of 25N. The very tight swirl is midway between the upper Keys and Cuba....
I am still watiting for proof in surface obs. Without the surface obs confirming/denying...we all know the National Hurricane Center isn't going to get excited....
Still, no hard feeling to PCola57
This system by florida should go NE right?
On the other hand, I would like to know and maybe others also want to know which one of you is a Certified Meteorologist or Meteorology Student.
i hope to be a meteorology student in a few years, so i can double major in that and Mathematics.
a low off the NC coast
the worst i remember were the floods in GA in 2009, We had TS FAY drop 10 inches one day, and 10-13 inches fell from leftover moisture on some other days, with lots of training thunderstorms.
The raindrops were huge and i remember it sounded like it was hailing sometimes.
We ended with 21.1 inches at my house, and every creek, depression, and even some flat places were flooded.
Good for you, I wish you success !
Viewing: 1001 - 1051
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 — Blog Index