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: 1114 - 1064

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

NEW BLOG!!!!!
Member Since: Posts: Comments:
HERE Is a great LOOP I look at daily.....see the Second HIGH Moving EAST out of MEXICO....yes there will be a weakness in between the 2 highs....that is what the Cold front was to break down.....NOT much of a cold front cause it is flattening out across the ConUS! I may be wrong but this is why i am a idiot at this stuff compared to the professionals.

http://www.atmos.washington.edu/~ovens/loops/wxlo op.cgi?wv_east_enhanced+12


Member Since: Posts: Comments:
Quoting cchsweatherman:
Anyone know which model runs will have the G-IV plane data from overnight in them?
check new blog and I'll tell ya
Member Since: Posts: Comments:
NEW BLOG ENTRY
Member Since: Posts: Comments:
Anyone know which model runs will have the G-IV plane data from overnight in them?
Member Since: April 14, 2007 Posts: 8 Comments: 5169
1109. eddye
that is why i said florida needs to keep a good eye on this one
Member Since: Posts: Comments:






Above on Satellite is the developing Cold front trying to develop off the NOrthern Coast of California.....seems pretty weak to me....See the developing HIGH in MEXICO...
Member Since: Posts: Comments:
Reminding me a little of Mitch in 98. Moves west then stalls and meanders SW and South and hugs the northern coast of Hondurus/Nicaragua
Member Since: Posts: Comments:
Quoting TampaSpin:


Tracks seem to be shifting north now, not west.
Member Since: Posts: Comments:
1105. eddye
tampaspin that is why we are watching rita in florida because it can pose a threat to us
Member Since: Posts: Comments:
1104. eddye
watch out wilma part 2
Member Since: Posts: Comments:
Member Since: Posts: Comments:
To the tourists who say "I'm willing to chance it" and continue with their trip to the Yucatan - I notice virtually all the models include the Yucatan in their plans. I wonder if these will be the tourists on TV talking about their horrible experiences being "caught" in a hurricane, unable to fly out, with no power and blown out hotel windows. One of my relatives insisted on continuing a fishing trip to Cabo San Lucas when a hurricane was pending. He then whined for months about how the storm ruined his fun.
Member Since: Posts: Comments:
Quoting TampaSpin:
Rina is gonna go west onto the Yucatan....that is the reason for the loop with the models....she misses the trough....WATCH the models today all shift west...
That's not the reason for the loop. The reason they loop her is that they say she will get sheared to death and her weak circulation will no longer follow the mid level tropospheric flow. The NHC has been consistent in saying this.
Member Since: Posts: Comments:
Quoting RescueAFR:
Good morning everyone from south fla.. sorry if this is duplicate post.. wanted to share an update from SFWMD..
South Florida Water Management District
Tropical Conditions Report
8:54AM Tuesday, October 25, 2011 (eps)

Current Conditions:

LOCAL STORM/HURRICANE WATCHES/WARNINGS: None.
Tropical Storm Force or Greater Winds Within 48 Hours: No.


DISCUSSION:

At 8am, HURRICANE RINA was located near 17.4N 83.8W, or about 305 miles east-southeast of the Chetumal, Mexico, moving west-northwest near 3 mph with sustained winds up to 100 mph. Strengthening is forecast as Rina slowly moves generally westward and northwestward over the next couple of days. Beyond that, a turn more northward and then eastward with weakening is expected as a cold front pushes southward through Florida Saturday. This front decreases the potential of a threat to the District.

A low pressure area is generating disorganized showers and thunderstorms over the southcentral Caribbean. Development is not very likely as the system moves generally westward. This system is not a threat to the District.


funny NHC Miami think diffrently the SFWMD with 97L

AN AREA OF LOW PRESSURE OVER THE SOUTH-CENTRAL CARIBBEAN SEA IS
PRODUCING DISORGANIZED SHOWER AND THUNDERSTORM ACTIVITY. UPPER-
LEVEL WINDS ARE EXPECTED TO BECOME MORE FAVORABLE FOR SOME GRADUAL
DEVELOPMENT OF THIS SYSTEM OVER THE NEXT COUPLE OF DAYS AS IT MOVES
WEST-NORTHWESTWARD AT 15 TO 20 MPH. THIS SYSTEM HAS A MEDIUM
CHANCE...30 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS
. LOCALLY HEAVY RAINS ARE POSSIBLE OVER ARUBA...CURACAO
AND BONAIRE...THE NORTHWESTERN COAST OF VENEZUELA...AND THE
NORTHEASTERN COAST OF COLOMBIA TODAY. FOR ADDITIONAL INFORMATION...
PLEASE SEE INFORMATION FROM YOUR LOCAL WEATHER OFFICE.

Member Since: Posts: Comments:



ALL the BAM MODELS now it her over land by a great amount....
Member Since: Posts: Comments:
Rina is gonna go west onto the Yucatan....that is the reason for the loop with the models....she misses the trough....WATCH the models today all shift west...
Member Since: Posts: Comments:
Quoting BenBIogger:


Moisture from 97L might give Rina a boost later on.

I think its more the other way around moisture from Rena might boost 97L
Member Since: Posts: Comments:
1096. Skyepony (Mod)
Quoting BenBIogger:


Moisture from 97L might give Rina a boost later on.


Looking at comment 1078 you maybe right. 97L has excessive moisture to work with.
Member Since: Posts: Comments:
Pretty good shift with models overnite....taking Rina more WEST...


Member Since: Posts: Comments:
Good morning everyone from south fla.. sorry if this is duplicate post.. wanted to share an update from SFWMD..
South Florida Water Management District
Tropical Conditions Report
8:54AM Tuesday, October 25, 2011 (eps)

Current Conditions:

LOCAL STORM/HURRICANE WATCHES/WARNINGS: None.
Tropical Storm Force or Greater Winds Within 48 Hours: No.


DISCUSSION:

At 8am, HURRICANE RINA was located near 17.4N 83.8W, or about 305 miles east-southeast of the Chetumal, Mexico, moving west-northwest near 3 mph with sustained winds up to 100 mph. Strengthening is forecast as Rina slowly moves generally westward and northwestward over the next couple of days. Beyond that, a turn more northward and then eastward with weakening is expected as a cold front pushes southward through Florida Saturday. This front decreases the potential of a threat to the District.

A low pressure area is generating disorganized showers and thunderstorms over the southcentral Caribbean. Development is not very likely as the system moves generally westward. This system is not a threat to the District.
Member Since: Posts: Comments:
Quoting Skyepony:


That's referred to as a uniform CDO, not an eye..

Also read page 27-29 here..


Moisture from 97L might give Rina a boost later on.
Member Since: Posts: Comments:
I expect Rina to become a cinnamon roll in the coming days. Eventually dry air should get into her core. She is holding up nicely for now.
Member Since: Posts: Comments:
1090. Skyepony (Mod)
Quoting wunderkidcayman:

yes there is it just not cleared out yet started to but not fully cleared out its near 17.5N 83.8W


That's referred to as a uniform CDO, not an eye..

Also read page 27-29 here..
Member Since: Posts: Comments:
Eye wall is still open. Its 60-70% Closed. IMO
Member Since: Posts: Comments:
Quoting RitaEvac:
Miami (CNN) -- Worried travelers and those living on Mexico's Yucatan Peninsula were waiting and watching Hurricane Rina on Tuesday after the storm intensified to a Category 2 and appeared poised to make a near-direct hit on the resort town of Cancun later this week.

Rina's maximum sustained winds were near 100 mph Tuesday morning, according to the Miami-based National Hurricane Center. "Additional strengthening is forecast during the next day or so and Rina could become a major hurricane by tonight or early Wednesday," forecasters said.

Forecast models show Rina strengthening into a major, or Category 3, hurricane before approaching the Yucatan. The projected path shows Rina back at Category 2 intensity when it takes aim at Cancun on Thursday.

Those headed for Cancun posted on some online travel forums seeking advice.

"I don't mind staying in the hotel as long as they don't evacuate us" and the power stays on, one person, who is planning to travel to Cancun on Saturday, wrote on tripadvisor.com.

"So how bad does the weather need to get before they cancel a flight?" another person wrote on a Cancun forum. "We're wiling to chance it."

There was no information regarding flight cancellations as of Tuesday morning.

The developments came as the search continued for more than two dozen missing storm evacuees from Nicaragua.

A navy boat ferrying people between the Miskito Cays and Puerto Cabezas, on Nicaragua's eastern coast, was reported missing on Sunday, according to Vice Adm. Roger Gonzalez of the Nicaraguan navy. Twenty-seven people were on board, he said.

As of 8 a.m. ET, the center of Rina was about 215 miles (345 kilometers) southwest of Grand Cayman and about 305 miles (490 kilometers) east-southeast of Chetumal, Mexico. It was meandering west-northwest at near 3 mph (6 kph), but was expected to gradually turn northeast and speed up over the next two days, forecasters said. "On the forecast track, the center of Rina will approach the east coast of the Yucatan Peninsula by Thursday morning."

A hurricane watch was in effect for the east coast of the peninsula, from north of Punta Gruesa to Cancun. A tropical storm watch is in effect from Chetumal to Punta Gruesa. The watches mean that hurricane or tropical storm conditions are possible within 48 hours.

Tropical storm conditions, including winds of at least 39 mph, are possible in the watch areas by late Wednesday, the Hurricane Center said. Hurricane conditions, including winds of at least 74 mph, are possible by early Thursday.

"It is too early to speculate what, if any effects Rina will have on the U.S., but after the storm makes landfall in the Yucatan, the combination of land interaction and high shear that is forecast into the Gulf of Mexico is expected to weaken Rina as it begins to turn toward the northeast toward Cuba, or perhaps South Florida or the Bahamas," said CNN meteorologist Dave Hennen.

The storm is expected to dump a total of 2 to 4 inches of rain over the Cayman Islands


Dear Lord...deaths from Rina already? And she hasn't made landfall and is still getting stronger? Prayers for all those folks in Central America, Cancun, and all islands. Even though she may be little in size, looks like she is already packing a punch.
On another note, we are all concentrating so hard on Rina and 97L, has anyone besides myself checked on the big picture...aka the whole Atlantic? There is another wave out there that is looking kinda healthy (possible 98L??) and a BIG blog of convection just exited Africa (yep, I know that the SAL season is technically over, but the stuff just keeps on coming off the coast...thought the rainy season was supposed to be over). Just wondering if this crazy, weird season is ever going to end! LOL
Another CRAZY thought...December storm anyone????
Member Since: Posts: Comments:
looks like the spaghetti models are beginning to trend northward a little
Member Since: Posts: Comments:
With latest GFS model suggesting that Rina may be hung up near the Florida Keys next weekend wouldn't be surprised that South Florida maybe put into the cone of uncertainty at 11am advisory from NHC
Member Since: Posts: Comments:
Quoting kmanhurricaneman:
there is no eye as yet guys!!

yes there is it just not cleared out yet started to but not fully cleared out its near 17.5N 83.8W
Member Since: Posts: Comments:
there is no eye as yet guys!!
Member Since: Posts: Comments:
1083. hydrus
Quoting CaicosRetiredSailor:
Good morning C.R.S..It has been a while since I have seen you post..Do you depict an eye in that satellite pic? If there is one, clouds are doin a fine job covering it up..
Member Since: Posts: Comments:
oh crap yep sorry I meant 14N 68/69W
Member Since: Posts: Comments:
Miami (CNN) -- Worried travelers and those living on Mexico's Yucatan Peninsula were waiting and watching Hurricane Rina on Tuesday after the storm intensified to a Category 2 and appeared poised to make a near-direct hit on the resort town of Cancun later this week.

Rina's maximum sustained winds were near 100 mph Tuesday morning, according to the Miami-based National Hurricane Center. "Additional strengthening is forecast during the next day or so and Rina could become a major hurricane by tonight or early Wednesday," forecasters said.

Forecast models show Rina strengthening into a major, or Category 3, hurricane before approaching the Yucatan. The projected path shows Rina back at Category 2 intensity when it takes aim at Cancun on Thursday.

Those headed for Cancun posted on some online travel forums seeking advice.

"I don't mind staying in the hotel as long as they don't evacuate us" and the power stays on, one person, who is planning to travel to Cancun on Saturday, wrote on tripadvisor.com.

"So how bad does the weather need to get before they cancel a flight?" another person wrote on a Cancun forum. "We're wiling to chance it."

There was no information regarding flight cancellations as of Tuesday morning.

The developments came as the search continued for more than two dozen missing storm evacuees from Nicaragua.

A navy boat ferrying people between the Miskito Cays and Puerto Cabezas, on Nicaragua's eastern coast, was reported missing on Sunday, according to Vice Adm. Roger Gonzalez of the Nicaraguan navy. Twenty-seven people were on board, he said.

As of 8 a.m. ET, the center of Rina was about 215 miles (345 kilometers) southwest of Grand Cayman and about 305 miles (490 kilometers) east-southeast of Chetumal, Mexico. It was meandering west-northwest at near 3 mph (6 kph), but was expected to gradually turn northeast and speed up over the next two days, forecasters said. "On the forecast track, the center of Rina will approach the east coast of the Yucatan Peninsula by Thursday morning."

A hurricane watch was in effect for the east coast of the peninsula, from north of Punta Gruesa to Cancun. A tropical storm watch is in effect from Chetumal to Punta Gruesa. The watches mean that hurricane or tropical storm conditions are possible within 48 hours.

Tropical storm conditions, including winds of at least 39 mph, are possible in the watch areas by late Wednesday, the Hurricane Center said. Hurricane conditions, including winds of at least 74 mph, are possible by early Thursday.

"It is too early to speculate what, if any effects Rina will have on the U.S., but after the storm makes landfall in the Yucatan, the combination of land interaction and high shear that is forecast into the Gulf of Mexico is expected to weaken Rina as it begins to turn toward the northeast toward Cuba, or perhaps South Florida or the Bahamas," said CNN meteorologist Dave Hennen.

The storm is expected to dump a total of 2 to 4 inches of rain over the Cayman Islands
Member Since: Posts: Comments:
Member Since: Posts: Comments:
wonderkid:)
I think u mean 69W and not 78/79W for 97 invest
Member Since: Posts: Comments:
1078. hydrus
Quoting TropicTraveler:
Roatangardener reminds me to worry about those in harms way - as Rina gets larger and wobbles around its impact will be felt by a whole lot of folks. Stay safe. My friends say "Hide from the wind, run from the water."
This a rare situation. Here it is late October and the potential for two named systems in the Caribbean Sea simulaneously.
Member Since: Posts: Comments:
Quoting wunderkidcayman:
yes and by my calculation the COC is in the new blob of convection near 14N 78W/79W
you mean 14.0n and 68-69w
Member Since: Posts: Comments:
Quoting hydrus:
I still cannot see an eye structure on satellite. Looks rather intense though..

I see.......
An eye.
Member Since: Posts: Comments:
Quoting barotropic:


Yeah....Grow and Grow......cause all kinds of misery for people. Cant fricken wait!

LOL yeah I guess
Member Since: Posts: Comments:
yes and by my calculation the COC is in the new blob of convection near 14N 78W/79W
Member Since: Posts: Comments:
1072. hydrus
Quoting weatherman12345:
brings a ts to southfla. this should change the track quite a bit considering the nhc relies heavily on the gfs.
I think that Rina and 97L will at the very least will give The Keys and South Florida some gusty winds and a good soaking.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Roatangardener reminds me to worry about those in harms way - as Rina gets larger and wobbles around its impact will be felt by a whole lot of folks. Stay safe. My friends say "Hide from the wind, run from the water."
Member Since: Posts: Comments:
1069. hydrus
I still cannot see an eye structure on satellite. Looks rather intense though..
Member Since: Posts: Comments:
well cayman at least, it appears that organisation has began.
Member Since: Posts: Comments:
1066. eddye
watch out keys and south fl wilma part 2
Member Since: Posts: Comments:
Quoting kmanhurricaneman:
WE NEED TO PAY SPECIAL ATTENTION TO 97L

ya think
Member Since: Posts: Comments:
WE NEED TO PAY SPECIAL ATTENTION TO 97L
Member Since: Posts: Comments:

Viewing: 1114 - 1064

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.