Rina rapidly intensifies into a hurricane

By: Dr. Jeff Masters , 7:59 PM GMT on October 24, 2011

Share this Blog
34
+

Rina is now a hurricane, just 21 hours after becoming a tropical depression. An Air Force Reserve hurricane hunter aircraft found winds of 75 mph--Category 1 hurricane strength--at 1:40 pm EDT in the north eyewall of Rina, using their SFMR surface wind instrument. Winds at flight level of 5,000 feet peaked at 78 mph, which typically translates to surface winds of 62 mph. On their second pass through the eye at 3:30 pm EDT, the winds were about 5 mph less, but the central pressure had fallen by two millibars, to 989 mb. Visible satellite loops show that Rina now has an eye, and the storm is steadily expanding in size and developing an impressive upper-level outflow channel to the north. Wind shear is a moderate 15 - 20 knots due to strong upper-level winds out of the southeast, and these winds are injecting dry air into Rina's southeast side, inhibiting heavy thunderstorm development there. Water temperatures are very warm, 29 - 30°C, and these warm waters extend to great depth.


Figure 1. Afternoon satellite image of Rina. An intense thunderstorm with a top that reaches into the stratosphere is visible on the southwest side of the eye. These "hot towers" are commonly seen in hurricanes undergoing rapid intensification.

Rina in historical context
Rina intensified into a hurricane just 21 hours after the first advisory was issued for it as a tropical depression. This is the second fastest such intensification since record keeping began in 1851. Hurricane Humberto of 2007 holds the Atlantic record for fastest intensification from first advisory issued to hurricane strength--18 hours. (Actually, Humberto did the feat in 14 1/4 hours, but this was rounded off to 18 hours in the final data base, which stores points every six hours). There have been six storms that accomplished the feat in 24 hours. Rina's formation brings this year's tally of hurricanes to six, which is average for an Atlantic hurricane season. The number of named storms this season is now seventeen, making it the 7th busiest Atlantic hurricane season since record keeping began in 1851. Only 2005, 1933, 1995, 1887, 2010, and 1969 had more named storms. However, 2011 has had an unusually low percentage of its named storms reach hurricane strength. Only 35% of this year's named storms have made it to hurricane strength, and normally 55 - 60% of all named storms intensify to hurricane strength in the Atlantic. The rare combination of near-record ocean temperatures but unusually dry, stable air over the Atlantic is no doubt at least partially responsible for this very unusual occurrence.


Figure 2. Microwave satellite image from 11:39 am EDT October 24, 2011, showing that Rina had a partially complete eyewall, which was open on the east side. Image credit: Navy Research Lab, Monterey.

Forecast for Rina
The hurricane hunters found an elliptical eyewall that had a gap in it during their 3:30 pm eye penetration. The aircraft measured a temperature difference of 6°C between the eye and the region outside the eye, which is difficult to get unless an eyewall is on its way to completion. Rina will need to complete its eyewall if it is to intensify into a major hurricane. Given the fact wind shear is not expected to increase until Wednesday, Rina has a 2-day period to close off an eyewall and intensify, and it will probably reach Category 3 or Category 4 strength by Wednesday. On Wednesday, Rina will encounter a dry airmass with high wind shear that lies over the extreme northwestern Caribbean. These conditions should weaken the hurricane, but Rina could still be a major hurricane if it makes landfall in the Yucatan Peninsula on Wednesday or Thursday.

A trough of low pressure is predicted to pass to the north of Rina late this week, and now that the hurricane is expected to be a Category 2 or stronger storm, the chances for Rina to make it farther north and affect the Florida Keys and Southwest Florida have increased. The latest 8 am EDT runs of the GFDL and HWRF models both predict that Rina will pass through the Yucatan Channel on Thursday and make landfall on Friday in the Florida Keys or extreme Southwest Florida, south of Naples. The NOGAPS and GFS models predict a weaker storm, and keep Rina trapped in the Caribbean. I think it is more likely that Rina will pass through the Keys. If Rina does make it to the Keys, it would likely be as a tropical storm, since wind shear, dry air, and possible land interaction with Western Cuba and Mexico would potentially knock down the storm's strength. Heavy rains from Rina should begin affecting Mexico's Yucatan Peninsula, northern Belize, and extreme Western Cuba on Wednesday. Rina's intensification into a hurricane over the Western Caribbean during the last half of October bring to mind Hurricane Wilma, which also performed such a feat in 2005. Wilma went on to become a Category 5 monster, the strongest Atlantic hurricane of all-time. I don't think Rina will be another Wilma, even though the ocean temperatures and total heat content are similar to what Wilma experienced. Wilma had nearly ideal upper-level atmospheric conditions with an anticyclone aloft and light wind shear, under 5 knots. Rina is experiencing 15 - 20 knots of wind shear and is also a smaller storm, and is thus more vulnerable to the effects of wind shear and dry air.

97L approaching ABC islands
A broad region of low pressure approaching the ABC islands of Aruba, Bonaire, and Curacao (Invest 97L), is moving west-northwest at 10 mph. Heavy thunderstorm activity has increased today, but the activity is not organized into spiral bands, as is apparent from Curacao radar. 97L is surrounded by a large region of dry air, and this dry air will retard development. 97L is under low wind shear less than 10 knots, and this shear is expected to remain low through Thursday. By the time 97L reaches the region between Jamaica and Nicaragua in the Central Caribbean on Thursday or Friday, the storm should find a moister environment, and could develop into a tropical depression. However, none of the reliable models are predicting that 97L will develop. NHC is giving 97L just a 10% chance of developing into a tropical depression by Wednesday. I put the odds higher, at 20%.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 514 - 464

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23Blog Index

Quoting Levi32:
In my opinion this is a great forecast, both track and intensity. She maxes just under Cat 3 and falls to a TS at Florida.

shows some interaction with the yucatan.. i agree with everything although a cat 1 isnt out of the relm of possibilities
Member Since: August 23, 2011 Posts: 0 Comments: 1724



NOt much warmer than where she is now.
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:

LOL! I get it!

Rina is going to be a force to recon with in the morning.

Rina: Recon, May the force be with you!!!!
Member Since: Posts: Comments:
Quoting WeatherNerdPR:

Covergae?


Coverage lol

Off for dinner
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:

I was talking in terms of winds.



oh lool
Member Since: Posts: Comments:
Both systems look healthy.


Member Since: April 24, 2011 Posts: 1 Comments: 601
Quoting Tazmanian:




yes there is the mb is down too 987mb from 989mb

I was talking in terms of winds.
Member Since: July 6, 2010 Posts: 113 Comments: 32039
In my opinion this is a great forecast, both track and intensity. She maxes right at the Cat 2/3 threshold and falls to a TS at Florida.

Member Since: Posts: Comments:
Quoting kmanislander:


Cold and expanding in aerial covergae. Probably the next leg up in the intensification process.


Covergae?
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:
According to ATCF, there is no change with Rina.

AL, 18, 2011102500, , BEST, 0, 172N, 832W, 65, 987, HU, 64, NEQ, 15, 10, 0, 15, 1012, 210, 10, 0, 0, L, 0, , 0, 0, RINA, D,




yes there is the mb is down too 987mb from 989mb
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Quoting Levi32:


Yes, Fairbanks.

So how much snow have you gotten? Or is it just cold dry weather?
Member Since: Posts: Comments:
Quoting ProgressivePulse:
Round she goes. Thought it would take longer personally. Rina is going to be a force to recon with in the morning.


LOL! I get it!

Rina is going to be a force to recon with in the morning.
Member Since: July 6, 2010 Posts: 113 Comments: 32039
Quoting Levi32:
Rina is generating the coldest cloud tops that we have seen in over 9 hours.



Cold and expanding in aerial coverage. Probably the next leg up in the intensification process.

Member Since: Posts: Comments:
Round she goes. Thought it would take longer personally. Rina is going to be a force to recon with in the morning.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
According to ATCF, there is no change with Rina.

AL, 18, 2011102500, , BEST, 0, 172N, 832W, 65, 987, HU, 64, NEQ, 15, 10, 0, 15, 1012, 210, 10, 0, 0, L, 0, , 0, 0, RINA, D,
Member Since: July 6, 2010 Posts: 113 Comments: 32039
Quoting Thunderpig75:


Lick em before you throw em so they stick.

LOL!
Member Since: Posts: Comments:
Quoting WoodyFL:


Could be an interesting week Levi. You are in Alaska, right?



Yes, Fairbanks.
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:

Thanks.

Does it have a good possibility of becoming a Category 3/4 storm like the Statistical models are saying?



P.S. I believe the NHC will be running models like the GFDL and HWRF again, because the site I got the image above from didn't have 97L up earlier today, with models and models tracks, etc.


Could be an interesting week Levi. You are in Alaska, right?

Member Since: April 24, 2011 Posts: 1 Comments: 601
Member Since: Posts: Comments:
Quoting Thunderpig75:


Lick em before you throw em so they stick.

LOL
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:

Is that a spiral band developing?


Yes it's had those for quite a while. This is the first large and distinguishing one though.
Member Since: Posts: Comments:
Quoting dolphingalrules:


but i make jello shots for the neighborhood on halloween,


Lick em before you throw em so they stick.
Member Since: Posts: Comments:
Can someone updated model tracks for Rina? (8 P.M. ones)
Member Since: June 21, 2010 Posts: 0 Comments: 528
Quoting TropicalAnalystwx13:

Thanks.

Does it have a good possibility of becoming a Category 3/4 storm like the Statistical models are saying?



P.S. I believe the NHC will be running models like the GFDL and HWRF again, because the site I got the image above from didn't have 97L up earlier today, with models and models tracks, etc.


I don't think anyone could make an educated guess about what category of hurricane 97L could become right now. We don't even know if it will develop. I would define its chances of developing as deceptively good, but nothing more than that can be confidently predicted right now.
Member Since: Posts: Comments:
Quoting Neapolitan:

ftp://ftp.tpc.ncep.noaa.gov/atcf/tcweb/

Thank you.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
The cloud tops have significantly cooled in the past three hours, with an outflow and presentation more characteristic of a Category Two Hurricane. Will have to wait for Atlantic sunlight to see if the hot towers have persisted.
Member Since: Posts: Comments:
Quoting Levi32:
Rina is generating the coldest cloud tops that we have seen in over 9 hours.


Is that a spiral band developing?
Member Since: July 6, 2010 Posts: 113 Comments: 32039
Quoting TropicalAnalystwx13:

LOL!


but i make jello shots for the neighborhood on halloween,
Member Since: August 18, 2009 Posts: 0 Comments: 192
Quoting Articuno:

Forgot, where do you get the HH info at?
I am new to this stuff.

ftp://ftp.tpc.ncep.noaa.gov/atcf/tcweb/
Member Since: Posts: Comments:
Rina is generating the coldest cloud tops that we have seen in over 9 hours.

Member Since: Posts: Comments:
Quoting shawn26:
When is the next HH scheduled?

1800Z, 0000Z, 0600Z, 1200Z.
Member Since: July 6, 2010 Posts: 113 Comments: 32039
Rina's looking good. Is it August or October? She won't pull a Wilma, will she? Sheer/dry air?
Member Since: Posts: Comments:
When is the next HH scheduled?
Member Since: Posts: Comments:
Quoting Neapolitan:
No change in wind or pressure for 97L; 0.2 degrees north and 1.5 degrees west of the previous fix:

AL, 97, 2011102500, , BEST, 0, 125N, 643W, 25, 1007, LO, 0, , 0, 0, 0, 0, 1010, 200, 100, 0, 0,

Forgot, where do you get the HH info at?
I am new to this stuff.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Quoting ClaySFL:


ROFL Interfering with what? You saw the others post about how they're getting annoyed. C'mon man, enough with the games.






no commets
Member Since: Posts: Comments:
Quoting Levi32:


It's on the table. Try not to be too excited about that.
ive got a stormchaser there and he really wants rina there because he hasnt chased a storm since wilma. plus florida could use some beneficial rain especially up in the panhandle
Member Since: August 23, 2011 Posts: 0 Comments: 1724
Quoting Levi32:


You mean the statistical guidance suggests that conditions ahead of it are favorable, and that's all they are telling you. I don't see the GFDL and HWRF or any other dynamic intensity models being run on it.

The statistical models are right that conditions ahead are favorable, and it should be watched, but as some have said, don't expect much until it's nearing Jamaica's longitude or farther west. It may find a sweet spot if we have a strong Hurricane Rina off the NE Yucatan in 3-4 days, similar to the chain formation that Cape Verde systems form, in which each system supports another.

Thanks.

Does it have a good possibility of becoming a Category 3/4 storm like the Statistical models are saying?



P.S. I believe the NHC will be running models like the GFDL and HWRF again, because the site I got the image above from didn't have 97L up earlier today, with models and models tracks, etc.
Member Since: July 6, 2010 Posts: 113 Comments: 32039
No change in wind or pressure for 97L; 0.2 degrees north and 1.5 degrees west of the previous fix:

AL, 97, 2011102500, , BEST, 0, 125N, 643W, 25, 1007, LO, 0, , 0, 0, 0, 0, 1010, 200, 100, 0, 0,
Member Since: Posts: Comments:
Quoting Tazmanian:




why not you mine your own BEE waxs and go about your own bloging


may be i sould poof you has well for interfearing


ROFL Interfering with what? You saw the others post about how they're getting annoyed. C'mon man, enough with the games.
Member Since: Posts: Comments:
Quoting wunderweatherman123:
levi what track will 97L mostly take? the bams show a dennis like track


I predict a more Nichole scenario. Due to this weekends front.
Member Since: Posts: Comments:
Quoting wunderweatherman123:
levi is a landfall in florida as a cat 1 still a possibility?


It's on the table. Try not to be too excited about that.
Member Since: Posts: Comments:
Quoting WoodyFL:


Just throw the candy at them as they blow by, they won't mind.


LOL!
Member Since: July 6, 2010 Posts: 113 Comments: 32039
Would not want to be on the Caymans right now.. Hope Rina heads North and gets outta your neighborhood soon!

Member Since: Posts: Comments:
be back later,
will pop in at 11 pm advisory to see what the NHC foresee's onto the situation
Member Since: Posts: Comments:
Quoting justcurious:
I have been shocked the last three times I have been on here. Yesterday shocked that there was a couple of invests, today shocked that we have a named storm, and now shocked that we have a hurricane.

Wonder if Rina will cancel the kiddies Halloween plans in sw florida? What say you, weather guru's?

Thanks


Just throw the candy at them as they blow by, they won't mind.

Member Since: April 24, 2011 Posts: 1 Comments: 601
Quoting Levi32:
Well with the upper winds looking like this in 72 hours, I would be worried about 97L too.

levi what track will 97L mostly take? the bams show a dennis like track
Member Since: August 23, 2011 Posts: 0 Comments: 1724
Quoting TropicalAnalystwx13:

Whats YOUR opinion on the Invest Levi, especially given that all the models bring it to hurricane status and further up to major hurricane status?


You mean the statistical guidance suggests that conditions ahead of it are favorable, and that's all they are telling you. I don't see the GFDL and HWRF or any other dynamic intensity models being run on it.

The statistical models are right that conditions ahead are favorable, and it should be watched, but as some have said, don't expect much until it's nearing Jamaica's longitude or farther west. It may find a sweet spot if we have a strong Hurricane Rina off the NE Yucatan in 3-4 days, similar to the chain formation that Cape Verde systems form, in which each system supports another.
Member Since: Posts: Comments:

Viewing: 514 - 464

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Mostly Cloudy
83 °F
Mostly Cloudy