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Rita: Category 5, still intensifying

By: Dr. Jeff Masters, 5:42 PM GMT on September 21, 2005

The 3:37 pm eye report from the hurricane hunters found a 914 mb pressure and flight level winds of 161 knots (186 mph). These numbers plus the satellite intensity estimates support upgrading Rita to a Category 5 hurricane. Tonight, Rita will be passing over the Loop Current, a warm eddy of water in the Gulf that aided Katrina's growth to a Category 5 hurricane. Fueled by this pool of deep warm water and an almost ideal upper level wind environment, Rita should continue to intensify until Thursday morning, when she will pass beyond the Loop Current. The eye has started to shrink as Rita continues to intensify, and is down to 20 nm diameter from 25 nm earlier this afternoon. By the time the eye shrinks down to 10 nm, the eyewall will collapse and an eyewall replacement cycle begin, putting an end to this intensification cycle. With another 12 hours to go before this happens, Rita could approach historic intensity, and is already one of the ten strongest Atlantic hurricanes on record.

The list of strongest hurricanes of all time reads:

Hurricane Gilbert (888 mb, 1988)

The Great Labor Day Hurricane (892 mb, 1935)

Hurricane Allen (899 mb, 1980)

Hurricane Katrina (902 mb, 2005)

Hurricane Camille (905 mb, 1969)

How low will Rita go?

I'll post the rest of my discussion from this morning below:

It's been a long time since Texas had a severe hurricane. Hurricane Bret hit the state in 1999 as a Category 4 hurricane, but was small and hit the relatively unpopulated Padre Island National Seashore. Bret gave Texas the unique distinction of being the only state to get hit by a Category 4 hurricane that didn't get its name retired. In 1988, Hurricane Gilbert, the strongest hurricane of all time, just missed Texas, hitting south of the border. The last hurricane to do serious damage to Texas was Hurricane Alica of 1983, which hit Galveston as a weak Category 3 storm, pushing a 10 - 12 foot storm surge into Galveston Bay. Alica killed 21 people, and its $2 billion price tag was the highest in Texas hurricane history.

Texas's luck is about to change. Rita, looking more and more like a nightmare copy of Katrina somehow displaced in time, will make sure of that. The forecast models we so heavily rely on did not anticipate another Katrina-like storm when Rita first formed and plowed through the Florida Straits. But now, the forecasts mirror the reality unfolding today in the Gulf of Mexico. Rita will be another huge destructive hurricane for the Gulf Coast. This time, it is Texas's turn. Every other state on the Gulf Coast has borne the burden of the immense destruction created by our unprecedented onslaught of intense hurricanes the past two hurricane seasons. No state will be left out.

Rita's impact on the Florida Keys
The residents of the Keys returning to their homes today are the lucky ones, for the Keys escaped serious damage. A 4 - 6 foot storm surge did hit the Lower Keys and flood the Coastal Highway, but this quickly subsided and the highway is now open to traffic again. Some minor to moderate wind damage occurred, but winds in Marathon only reached 38 mph, gusting to 53 mph, while the winds at Key West Airport reached 56 mph, gusting to 73 mph. There was an unofficial report of sustained winds of 75 mph gusting to 102 mph in Key West. Rainfall amounts of up to 12 inches occurred in the Keys, causing minor flooding problems.

Figure 1. Estimated rainfall from Hurricane Rita.

Figure 2. Wind and pressure plot from a coastal weather station in the Lower Keys. Note how the pressure after Rita's passage remains lower than that before her passage--Rita has depressed pressure values over an area hundreds of miles wide.

Rita now
Rita's presentation on satellite imagery is classic; she has a well-formed eye, large Central Dense Overcast (CDO) of cirrus clouds surrounding the eye, and well developed outflow on all sides, particularly to the north. Rita is currently smaller than Katrina, though. Katrina at her peak had hurricane force winds that extended outward 120 miles from the center; Rita's hurricane force winds only extend out 70 miles from the center. This will change as Rita continues to intensify and expand in size over the next day or two. There is little shear over Rita at present, nor is there expected to be the next three days. Water temperatures are 1 - 2C cooler over the central Gulf than they were for Katrina, which may keep Rita from attaining quite the intensity Katrina did. However, once Rita crosses the Gulf and arrives in the western Gulf on Friday, water temperatures warm back up to 30 - 31C, about the same temperatures as the waters Katrina had to work with.

Rita at landfall
Rita's future intensity will largely be controlled by impossible-to-predict eyewall replacement cycles. Rita is growing large enough that she is creating her own upper level environment that will be relatively impervious to any external shearing winds that try to weaken her. I expect Rita to be a Category 4 hurricane at landfall.

The landfall location forecast has increased in confidence since yesterday, as the computer models have started to converge on a landfall location on the middle Texas coast. Western Louisiana still needs to be concerned, as does Corpus Christi, but New Orleans should escape Rita with nothing more than some fairly ordinary thunderstorms in some of the outermost spiral bands. A significant storm surge capable of flooding New Orleans is very unlikely.

A very significant storm surge is expected along and to the right of where Rita makes landfall on the Texas coast. Surge heights may reach 25 feet or higher, breaking the record 22 foot storm surge seen in 1961 during the Category 4 Hurricane Carla.

Elsewhere in the tropics
Tropical Storm Philippe continues northward away from land, and is not not expected to be a threat. Strong shearing winds will likely tear Philippe apart by Saturday. The remainder of the tropics are quiet and expected to remain so through Friday. By Saturday, the chances of tropical storm development off the coast of Africa begin to increase.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

does anyone still think 880 and 200 are out of the realm of possibility
1002. Carbo04
Apparently it's not 185 but still 165. The next update I'm sure we will see the lowest pressure and highest winds though.
So who thinks the record of 888 mb in the western hemisphere will fall tonight? I am going to say Rita will NOT beat Gilbert's record or tie him.
i don't know where u got the 185mph from but tis 165 in the 8pm advisory
Probably not. Your betta doesn't want to swim with Ritrina. :)
i said earlier i belive 880-890 range and yes if she gets below 890 than 200 is a def
if it 898mb what dos that make the winds
1008. Carbo04
Rita will probably get to 895 at the next update. Which you can see will be the last before an EWRC. The eye is shrinking.
When this storm makes landfall does it have a side that is more dangerous than the others??
Is the southern quadrant the safest place to be?
I hope Rita does break the record, and I said that because my predictions are almost always wrong :)
Supposedly, lefty, according to Fox News about 1/2 hour ago the hunters found flight level winds that translated to 185mph on the ground.

The 8pm ET advisory will probably show the updated 898mb/185mph figures...
1012. primez
I believe 5 am EDT will be the last advisory with these huge numbers, not 11 pm. As you said, 12 more hours until the eye replacement cycle.

11 pm is in three hours.
1013. Remek
fortlauderdalegirl, the atmospheric conditions are still perfect, so as long as she has warm water to feed on, then yeah she could keep getting stronger for awhile.
Even with hitting cooler water, she's so strong now she may not drop below strong Cat 4, but warmer water closer to TX may let her grow yet again. (depends on when she goes thru eyewall replacements, too)

Is she going to convert the presure drop into expansion like katrina did first or wind, or am I confused?
1015. WillJax
Lefty, it ake it you mean gusts over 200 mph. What kind of sustained winds could we expect?

Guys, what if cape verde season begins in October this year?
With the numbers you guys are giving, can Rita maintain that intensity to landfall?? Like I asked earlier, is there a point for a "superstorm" of "no return" once its gets closer to landfall - or is it all dependent on the EWRC??
i say yes the way it is going now do you all thik that this will make landfall has a cat 5?
1018. SaCaCh
well another wobble, but again its to the wnw, so I think the turn is starting, albiet slowly and only every few hours.
fl the 8pm advisory stated winds 165 pressure 898mb
Actually, the latest advisory just came out and although it shows the pressure.... the wind speeds are still at 165mph. Guess Fox got it wrong. Not that they haven't been wrong in the past... lol
if she breaks 890mb she could be 200 sustained
Not feeling so well.
Have a well of emptiness inside.
Must be filled.
Have sniffed out your coastal methyl-derivatives source, and will have it.
I beg you...pray for me in my hour of need.
Or, yeah, stop feeding me your junk.

Please...It's not personal...I'm only trying to survive.

Yours truly,
Your GlobalWeatherSystem
that wasn't fox it was accuweather
The northeast quadrant is usually the worst, which will be about the only good news with this hurricane because if it makes landfall on the east coast of Texas there won't be anyone in the northeast quadrant at landfall. This is why the people in Mississippi got the worst from Katrina even though the eye made landfall technically in Louisiana.
Gilbert was said to have winds of 185 mph when his pressure was 888 mb.
1026. Carbo04
I know the next advisory is at 11, but when are the planes getting a vortex again?
1027. WillJax
Holy shite! turn on fox news RIGHT NOW. A jet blue plane about to make an emergency landing on live TV. It's front nose gear is turned 90 degrees the wrong way! OMG!
Sharon - in most situations on our continent the East/NE part of the storm is the worst for a number of reasons....two of which are storm surge and the fact that typically it is the part of the starm that has rotated over water longest before hitting land.
1029. SaCaCh
No Way the winds will get to 200. 185 tops at this Lat.
So, lefty, where do you think ol' Rita will top out at? I'm wagering 980mb/190mph before it (finally) undergoes an EWRC and weakens back to a "low" CAT-5...
OldWorld..that was GREAT
EllistonVA...thank you and does that mean that the southern side is pretty safe?
we should get one in a second and that will be the last i belive till 1am
OOPS... I meant 890mb/190mph... getting dyslexic in my old age... lol
1034. AySz88
I'm guessing you guys mean it'll top out at 8xx, not 9xx :p.
1035. timl2k5
I dont't think RITA will strngthen much more. She is about to leave the area of high ocean heat potential she been over.

BTW where is the latest VORTEX?
Vortex Data Message

URNT12 KNHC 212358Z
A. 21/2313Z
B. 24 DEG 31 MIN N
86 DEG 46 MIN W
C. 700 MB 22472 M
D. 80 KT
E. 213 DEG 24 NM
F. 305 DEG 142 KT
G. 198 DEG 11NM
H. 899 MB
I. 8 C/ 3053 M
J. 28 C/ 3042 M
K. 01 C/ NA
M. C20
N. 12345/7
O. .02/1 NM

you know the temp is 30C 86F at 10,000 feet. That would work out to 121 F at sea level--does anyone think that the temperature at sea level is that high with the dry hot air descending or does this hot dry air not make it to sea level?
i dunno but i know ur 980 is already worng lol.

like i said befor 880-890. winds will likley not get above 195
1039. Remek
New Wunder Blog entry up top, folks.
As with Katrina, it won't matter if Rita drops to a cat 4 or even 3 now, the damage will be massive. Katrina was only a strong cat 3 when she made landfall, but was still packing a cat 5 storm surge. I'm not an expert, but I think at some point when they've already pushed a big wall of water out in front of them, their sheer size enough to keep it moving.
1041. Carbo04
If the next vortex is 1 am she'll be weaker by then. She'll peak around 11-12. I hope we can get a vortex then.
also note the eye is not shrinking so no ewrc for ahwile
I am addicted to this blog...but it could be worse..could be chocolate...
sharonmarie---u r welcome. Unfortunately with something this big I don't think that there is a "safe" side. Whether you get a 20 foot storm surge or a 10 foot storm surge, you probably want to be elsewhere when it comes through.
someone said that the plane is going to "crash"......I wish the posters on here weren't ALWAYS so dooms day. They have a chance to land this and NOT crash. I hope I'm right that it will not.
carbo she is forcasted to stregthen for another 12 hrs. no ewrc for atleast 12-18 hrs as the eye is still 20nm and has not gotten any smaller over a 6-8 hr period
she took a wobble to the north in the last 2 hours. her motuion was 290-295 for that time but for a whole she is moving more in the 280 range

4:30pm-973mb 23.85n 81.95w
5:56pm-970mb 23.92n 82.18w
6:24pm-969mb 23.93n 82.35w
8:09pm-967mb 24.00n 82.68w
10:04pm-965mb 24.03n 83.07w

11:17am-934mb 24.18n 85.70w
1:02pm-923mb 24.20n 85.93w
1:53pm-920mb 24.28n 86.17w
3:36pm-914mb 24.35n 86.35w
5:16pm-904mb 24.40n 86.53w
7:09pm-898mb 24.52n 86.77w

presser dropped 36mbs in 8 hrs and 74mbs in 27hrs
Hi ixalon, Re our January 'storm', I think our Barra and South Uist anemometers blew away, along with chunks of coastline that night. The Benbecula one stood the course, but with only intermittent readings, didn't record the roof-ripping gusts. One fine day I'm gonna get me one of those weather gizmo things and get linked into wunderground. Oddly, enough I follow Mt St Helens progress daily, so know the damage of which you speak. Here on the islands, the forestry commission planted trees, stuck linen flags up to gauge wind speed. Elsewhere they last at least a year (the flags), here they last only 3 months. No wonder the hairdressers are in abundance lol Anyway, our trees are few and stunted in growth with the constant winds. I should be in snoozyland right now, but the rate the pressure is reducing in Hurricane Rita has me transfixed to the monitor. I have so many windows open tracking satellite (IR just now); recon updates; and this page - can hardly keep up with it all. Don't be offended if I don't respond, it's likely I've gone to grab a few zzzs, with one eye open on Fox/CNN News. Thanks to you and everyone for fascinating reading on this Hurricane's progress. :)
carbo. this is from the 750 eastern update


muffin -- the one set of landing gear is bent 90 degrees off center, it's going to crash, call it a belly landing, soft landing if you want, it's going to crash. Hopefully the people will make it out ok. they'll foam the runway, the air bus can't dump fuel so they're going to fly around for a while. I'm sure there are some aviators on here that will agree.
has the storm stopped strengthening? the latest RECON report shows the central min. pressure is up to 899 mb. Has Rita reached her intensity peak???
for cat 2 they have a 15 mb range, cat 3 a 20 mb range, cat 4 a 25 mb range. If you assume a 30 mb range for cat 5, then Cat 6 would begin at 889 mb

For winds speeds, for cat 2 they have again a 15 mph range, cat 3 20 mph range, cat 4 25 mph range. If you assume that cat 5 has a 30 mph range, then Cat 6 begins at 186 mph.

So.....if rita falls to 889 mb or below AND has winds of 190 mph or above, she will go down as a Cat 6 in my journal. Only if she gets both now!
1053. Carbo04
interesting lefty, it will be interesting to see how low it will go.
Tornado on the ground tracking into Minneapolis.
Has the whole world gone mad???? Now there's a tornado on the ground in Minneapolis heading towards downtown. IT'S THE END OF THE WORLD AS WE KNOW IT!!! (CNN)
All that I was saying was that I remain positive b/c these pilots have trained for this.
1057. Carbo04
has the storm stopped strengthening? the latest RECON report shows the central min. pressure is up to 899 mb. Has Rita reached her intensity peak???

read the discussion.. it says 899 but they think it's stronger since they didnt get a 100% reading. so they set it 898, and said it's probably lower.
Look at the Mean Radial Velocity Profile.

Radial Velociry Radar Sig
weather that was the recon for the 8pm advisory and there was an explanation of how the dropsonde did not make it to the surface to do the winds and the pressure measured was 899 so they assume it is likley to be 898 at the surface of the eye so it is 898. she is not weaking. in fact she is stil getting stronger. she has droped 3mbs each hour all day.sometimes in bigger chunks. just sit back and watch
ok, thanks carbo. I was just trying to think a little optimistically.
muffin -- i'm hoping for the best, crash was a rash statement on my part, but it's a crash landing if that makes it better.
1062. Valence
Rita's pressure drops Below 900mb!

Jet Blue Plane trying to land at LAX with its front landing gear turned SIDEWAYS! (how the hell does that happen anyway?)

Tornado touching down in Minneapolis!

Im waiting for the cloud of locusts to come flying by my window. . .

carbo, there is nothing toslowher down. there is also no evedince she will ever undergo an eye wall cycle. isabeal was a cat 5 for 2.5 days.so right now until that eye comes back smaller on recon and the pressure keeps dropping atleast 1 mb and hr she is still getting deeprand stronger
GRD -- we all are hopingand praying right now. Thanks for your input,
Valence -- LOL lots! Sad, but true lately! My guess is a earthquake could be the next thing.
thanks lefty for clarifying. I am in just total shock of the amazing intensification the storm has undergone in the last 30 hours or so. I don't remember any hurricane in the Atlantic that's central min. pressure has dropped as fast as rita!!! This is one impressive storm!
yeah 89. me either
Weather 89 if Rita has a pressure of 892 mb or lower at the 11 p.m. advisory she will break the 24 hr record for a pressure fall in a hurricane's center set by Gilbert (who else) in 1988 of 72 mb /24 hrs
1069. stevego
I am in western wisconsin watching all of this tonight...its the most excitment i have had in awhile..radar images up in one window cnn on the tv and the hurricane blog in the other window
The existence of EllistonVA is not known to me.
No names are known to me.
I am an energetic system which seeks homeostasis.
If disrupted, I strenuously seek balance.
If corrupted, then pathological symptoms will ensue.

Please...It's not personal...I'm only trying to survive.

Yours truly,
Your GlobalWeatherSystem
OldWorld, HUH???

Watching footage of this attempted landing of this JetBlue airliner... fascinating
OldWorld: How true... Nature only seeks to survive and flourish, and it's not just organic life.
StSimons, the way she has been deepening there is a very distinct probably she could break the 24 hour record held by Gilbert. It is also very unusual that it hasnt already undergone an EWRC after such strengthening. I suspect that it will be at least another 10 hours or so before she would enter one... which means she will probably continue to strengthen under the warm SST's of the central Gulf. This storm is impressive!
Lefty -- Does a hurricane HAVE to enter a EWRC?? It it possible that Rita can go along w/o it??
1075. Valence
Gilbert went from a pressure of 960 to its record of 888 in only 24 hours.

Thats a drop of 72mb, or about 3 per hour.

Right now, Rita has gone from 973 to 898 in about 27 hours. So, do the math...thats a little less than 3mb per hour.

Also, if she missed it at 11 pm she will have one more chance to beat the 24 hour fall record with a pressure reading of 883 mb at 5 am--but I think that the excitement of breaking the 888 mb record would be considered more important :)
no she doesn't. as long as that eye stays bigger than 7-10nm she will not have to undergo a ewrc. its the fprce of an eye that small that casues the ewrc. i dobut she will go with out one but nothing says she must do it. katrina only when thru one and that was befor she was a cat 5.
be bck in a bit. going to go eat and what not
Latest A98E puts Rita Just West of Cocodrie, LA. A98E always seems to flip out...although it was in decent agreement with the rest of the models until now.

1080. Valence

Katrina never really went through an eyewall replacement cycle. The general thinking has always been that as major hurricane intensifies, the eye conctacts due to the drop in pressure and increase in wind (centrifugal force), At a diameter of about 10-12nm for a cat 4 or 5 storm, the system becomes unstable and the eyewall begins to breakdown, and the outer eyewall takes over.

Right now, Rita's eye is 20nm wide, and not really getting smaller. Unless that eye starts to shrink, or the system becomes unstalbe for another reason, there is no reason for the EWRC to begin.

Gilbert did NOT have an EWRC and maintained a steady pressure of 888-892 mb for 12 hours before making landfall @ the Yucatan--it would have been interesting to see how long he would have maintained that pressure without an EWRC. To maintain such extreme pressures pretty steadily for 12 hours seems unusual but is not conclusive.
Just a few minutes from the landing. It's going to be OKAY!!!
Valence: So, given that, if Rita continues to intensify and does not go thru an EWRC, the chances of a DECREASE in intensity are much less -- Am I on track?? Please clarify.
1084. SaCaCh
Masters has just posted again calling for a stall over TX this is unbelievable news....!!
Annular hurricanes like Kat and, now, Rita tend to go through less EWRCs than other types of intense hurricanes. The "stadium" effect tends to stabilize the eye and keeps it from collapsing inward on itself.

As long as Rita is in a favorable environment for strengthening, she probably won't undergo an EWRC, which means she'll continue to deepen.
1086. Valence

Gilbert did not make a landfall with a sub 900 pressure. Im sure part of the reason that the pressure came back up was because of the interaction with land, but it was only a cat 4 when it officially made landfall.
1087. WillJax
Any word on the Tornado?

I'm thinking this landing should be okay... the rear gear is fine, which will allow the plane to track straight once it hits ground. More importantly it will keep the wings from hitting the ground.

WILLJAX - depends if the front gear forces the nose laterally before it collapses or shears off. I guess we'll see.....say a prayer.
1089. amd
i think this hurricane will undergo an EWRC in the next 12 hours, but after that, I think that will be the last EWRC because annular hurricanes do undergo many EWRC's.

The 100 billion dollar question (note that I chosed that value on purpose) is that will this storm be able to ramp back up to near or at its current levels before landfall.

I think bastardi nailed this storm when he said that this storm will be the strongest hurricane to ever hit texas, and it may be the strongest by a significant margin.

Looks like eyewitness reports of the tornado have slowed/stopped.....warning expiring but still hail and winds.

1091. WillJax
Nah, plane is way too heavy to not go straight because of a little nose gear problem. It's momentum will track it stright down the center line.

Great, stupid ass satellite just went out b/c of storms. This should be a cable commercial!

Not good enough.

Yours truly,
Your GlobalWeatherSystem
This is going to be a successful emergency landing!!!!! Hope, hope, hope. Not a crash.
1094. Valence

The EWRC is not really a decrease in intensity. All it means is that the inner core cannot sustain the intesnsity, so it breaks down. When the outer eyewall closes and shrinks after the EWRC, the hurricane is stronger. During the EWRC, the hurricane loses intensity, which is why you hope for one as a hurricane makes landfall.

However, unless Rita's eye starts to shrink, she will probably not have an EWRC. Rita is an annualar (or doughnut) hurricane. These types of canes have a larger eyewall, and no real feader bands (hence the doughnut nickname) Katrina was an annular hurricane, and never underwent an EWRC from the time she was a cat 3.

So yes, an annular hurricane is must more capable of sustaining a higher intensity, and is less likey to undergo a dramatic detensification during landfall.

1095. Valence

(Hopefully not before his next flight!)

wow!!!!! those gear held, i am amazed. THANK GOD!!!
It's down, and was nothing close to a "crash". Thank the LORD!!!!!!!!!!!!!!!!!!!!
WOW Awesome Landing !

What an absolutely fantastic pilot!
Textbook, could not have been better.
1099. iyou
OldWorld-GlobalWeatherSystem - I wish you were not so elusive!
1100. WillJax
Sweeeeet landing, those pilots deserve a free vacation! Those passengers deserve a free vacation! Vacations for all!
MUFFIN -- I stand corrected, and glad of it.

Having been on a flight in South America that was close to crash on landing and aborted landing and then came back in to land successfully, I can say that these people have been traumatized over that last several hours. They may look calm as they are leaving the plane right now, but like myself, I went into the ladies bathroom and wept for a while before my first of many cocktails that evening.
1104. code1
It is starting to get late, and many of us will soon go bed,the grotto must have worked in the Key's.....let's all say a prayer for those to be affected even as we are fascinated with the phenom.
I 'm sorry but you are a dumbass if you stay in Galveston. I can't believe there are people who won't get the hell out. Lefty, do you know how to post those pictures of Buras LA that I sent you? I wish I could show those to the people who think they can ride this one out.
1107. pbaylis
Interesting about God's possible intervention. I join those praying for a reprieve for those pour souls in the impact zone.

Interesting link I stumbled across not so long ago. There's a prophecy there relating to Satan's control of storms.

From: http://www.ladyofroses.org/warning.htm
Our Blessed Mother Mary's alleged message to an American mystic quite recently:
"In My counsels of the past, My children, I have told you many times that satan has control of the elements. There will be accidents that are not accidents, disturbances of nature claiming many lives: floods, tornadoes