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Western Caribbean disturbance generating heavy rains

By: Dr. Jeff Masters, 2:38 PM GMT on November 01, 2006

An area of disturbed weather in the Western Caribbean is associated with a tropical disturbance (93L). This disturbance has not gotten better organized over the past day, but has some potential for development over the next two days. The system does not have a well-defined surface circulation, but there is a sharp shift in wind direction along a line running from the western tip of Cuba down to the coast of Honduras, roughly along 85W longitude. QuikSCAT satellite-measured winds from 6:33pm EST last night were in the 20-30 mph range. This morning's QuikSCAT pass missed 93L, and we will have to wait until about 8:30pm EST tonight for the next pass to arrive. 93L will be near buoy 42056 at 20N 85W today. Winds at the buoy have been less than 15 mph the past two days. Wind shear increases from about 5 knots near the coast of Honduras to about 30 knots near Cuba. It is possible a well-defined surface circulation could develop along this wind shift line over the next day or two, but it is unlikely we'll see a tropical depression form. If a depression were to form, it would most likely affect Honduras, Belize, and Mexico's Yucatan, since wind shear is too high to the north. The disturbance should bring heavy rains to Belize, Honduras, and Mexico's Yucatan Peninsula Wednesday through Friday. At this time, it does not appear that 93L will affect South Florida, although moisture from the surface trough of low pressure 93L is embedded in will increase the chance of rain through Friday. Wind shear is expected to stay above 40 knots over the Gulf of Mexico, Florida, and the Bahamas over the next seven days, which will protect those regions from any tropical storms.


Figure 1. Preliminary models tracks for the Western Caribbean disturbance.

Typhoon Cimaron
Typhoon Cimaron has re-intensified to a major Category 3 storm, but its days of glory are numbered. The same trough of low pressure that is currently acting to steer the storm northwards towards Hong Kong is also expected to bring high wind shear over the storm beginning Thursday, and there is a good chance that Cimaron will get torn apart before it reaches China. Cimaron killed 19 people in the Philippines when it hit the mountainous northern portion of Luzon Island on Sunday. The storm injured 58 others, left 15 people missing, and damaged more than 5,000 homes.


Figure 2. Rainfall estimated by NASA's TRMM satellite for Typhoon Cimaron yesterday.

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

Posted By: MichaelSTL at 4:45 AM GMT on November 02, 2006.
How bad was it in Springfield?

It was nasty.....lots of wind and lightning, not much rain though. I was glad to be seeing it mostly in my rear-view mirror. Gotta say though, I just love driving through the Ozarks.....we used to go there a lot when we were kids.
Well Laura you sound like the type who likes too kick back and relax.
Wheres the chips and salsa I've gotta get this Hurricane Party started!

Sprocket....nice links. I've been in plenty of weather out there that would easily qualify as a 'cane down here. We used to go out to the Hoh rainforest for a storm watching weekend. Amazing....out there it's just another winter storm.....tough folks in the Pac NW!!!
LOVE to kick back, relax and watch a good storm blow through. Chipsl salsa.....some good blackstrap Rum and I'm good to go!!!
and MichaelSTL's 7:04 PM PST post is interesting too.

Has a graphic that projects it to become tropical!
It's not tropical, just another wild winter storm.
Where I live, it came though looking like a fog bank when the rain started, with visibility limited to less than 50 feet or so and horizontal rain (the wind picked up well before it even got here). When it was over, there were about a million leaves scattered all over the place (like in the fall, but the leaves were green); for the next few weeks, large piles of trees were a common sight along the street.
Come too Washington!
... eventually symetric warm-core.
Look at this 91C has a fully developed Eye wall!
My nephew, who lives in S'field sent me pics a couple of days after that storm....STL really got nailed. I had planned to go up to Jeff City for a few days of horseback riding with friends, but it was SO hot and all that damage just sent me back towards the gulf. Must say, we had a pretty nice summer down here this year.....much needed after all of last year's devastation. I'll get back up there though....lots of friends in your neck of the woods.
I can't drive on those straight flat roads without getting Highway Hypnosis!
Exratropical cyclone, that's all it is.
Wishcaster - I was out in May for a visit...the weather was fabulous. I make it out there a couple of times a year. Will actually be back again in December and again next may. Will spend a couple of months there next summer working with patients at Fred-Hutch cancer center in Seattle.
Are you a doctor?
STL large piles of everyting are STILL a common sight in New Orleans! Pretty sad state of affairs there still. Depressing really. Glad to be out of there.

Wish, baby...down here when you get that highway hypnosis, you're supposed to pull over and throw a line in the water!!!
Hurricane Rosa 91C should be!
it has 990 mb!! Thats the lowest ive ever seen
for a Invest idk what the NHC thats obviouslt a Hurricane Rosa!
LowerCal, the graph shows that it is already warm-core (the C marks the current phase). It looks like it, too. By the way, Vince actually looked just like 91C when it was still labeled as an invest:



This explains why "cold water" storms can develop; it depends on the temperature of the upper atmospshere (vertical axis), not just the SSTs (horizontal axis):

I am a PhD.....anthropology. I teach yoga classes to cancer patients here in Jacksonville and we're doing a test program with Fred-Hutch next year.
Of course Mike ... it's just one of those "entertaining" model runs.
This storm also comes in mind
Cybr....a perfect storm??
It is not entirely a model forecast; only the forecast part from C to Z is forecast; everything from the start to current is analyzed; in other words, they analyzed it as being warm-core.
the perfact storm happended 15 years ago
yesterday!
It's midnight......I'm about to turn into a pumpkin.....again! Nice being back in the US and even nicer being back on the blog. Thanks for the chat y'all.....I'll catch up with you again tomorrow and see what's up then. G'nite all....sweet dreams.
Thanks Michael. I always wondered why they included the "C", lol.

And of course that second part makes sense ... it just needs to be "colder enough" aloft.
The area marked "Hypercanes" on the graph I posted is just the area where models freak out (intensity increases exponentially with warmer SSTs and colder upper atmospheric temperatures until a point is reached where models can't calculate meaninful values). Also, in some cases, storms can actually exceed the maximum intensity that might be expected; for example, Gordon was stronger than what the maximum intensity charts indicated to be the maximum intensity in the area it was in. In other cases, storms may dissipate or fail to develop due to an unfavorable thermodynamic profile (a cap or unusually warm temperatures aloft) in the atmosphere, even when the water is warm.
That 130 m/s converts to about 290 mph!

...in other words, they analyzed it as being warm-core.
MargieKieper did some blogs on the NHC's apparent hesitancy about calling a system subtropical.
Apparently this is an example.
I am not sure what typical values for the upper atmospheric temperature are (the article says at 200 mb), but this CloudSat has the temperatures marked on it (bottom):


Click to enlarge

In this case, it appears to be around -55*C.

SSTs in the same area are around 27*C. Based on this, the maximum wind speed is around 70 m/s or 157 mph, which is what the maximum potential intensity map indicates (based on the same formula shown on the chart I posted earlier):



Pressure calculations are a little different; storms with the same wind speed can have vastly different pressures (such as Andrew at 175 mph and 922 mb and Katrina at 175 mph and 902 mb, or better, Wilma at 155 mph and 892 mb).
Fascinating and enlightening as always Michael. Thank you.

Fortunately Cimaron isn't hitting that maximum potential intensity now.
That storm is currently not strong enough to be labelled a "Kyrant".

Kyrants are winter storms that resemble Hurricanes. They can survive in places where Hurricanes cannot because they use the immediate environment for fuelling. What you are looking at isn't a "hypercane", it is a Polar Storm almost at Kyrant strength. The March 93 Superstorm was a Kyrant. Kyrants follow a category system very similar to the Hurricane Saffir-simpson scale. In Oceania (New Zealand and Australia) Kyrants and Polar storms are named in the ABC order (exactly the same way as Pacific and Atlantic Hurricanes are named). Kyrants however generally don't become as powerful as Hurricanes and it very rare that a Kyrant will reach Category 4 or even 5.
Good morning everyone. It has been a good yr. Lots of action no damage. Have a nice day.
Cyclone....it is not considered a freak wave. This scenario occurs in the far North Atlantic sometimes also when a storm is moving along at a speed that allows the waves trapped within to become enhanced and very large.
I think they call it a trapped fetch or something.
Thanks for that article. Interesting.
NWS is forecasting some sloppy conditions but there will be some waves to surf this weekend!


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL

MARINE...WILL BE STARTING A SMALL CRAFT ADVISORY AT 06Z TONIGHT
WITH POST-FRONTAL WIND SURGE. CONFIDENCE IS HIGH THAT WINDS WILL
FREQUENTLY GUST ABOVE 34 KT FRI AFT AND WILL BE ISSUING A GALE
WARNING. LATEST WAVE WATCH SUGGESTS SEAS MAY EXCEED 12-14 FTFRI-SAT...THOUGH HIGHER SEAS ARE CERTAINLY POSSIBLE IN THE GULF
STREAM. RELENTLESS NORTHEAST FLOW WILL LIKELY PRODUCE EXTREMELY
ROUGH SURF AND AREAS OF BEACH EROSION INTO EARLY NEXT WEEK.
LATEST WAVE WATCH SUGGESTS SEAS MAY EXCEED 12-14 FTFRI-SAT

is this on our lovely shores?....cus if so....there's gonna be an old man out on jensen bech this weekend..come on..grab your baggies and your boards..now..if i just had a woody
Don't be discussing your woody on here!
re: "Don't be discussing your woody on here!"


or lack thereof......good morning all, some more good rain headed our way, jo
oops...that didn't look right...looks funny..but not right..LOL
some more good rain headed our way, jo

Morning Jo. Probably be a rainy day today for sure.
nws 5 am ".DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.
WINDS WILL STRENGTHEN FRIDAY...RESULTING IN WINDY CONDITIONS OVER
LAND AREAS. FURTHER DETERIORATION IN CONDITIONS OVER THE COASTAL
WATERS WILL OCCUR...WITH FREQUENT WIND GUSTS TO GALE FORCE EXPECTED
FRIDAY AFTERNOON THROUGH EVENING AND SEAS BUILDING UP TO 15 FEET
OFFSHORE FRIDAY NIGHT. ONLY A SLIGHT ABATEMENT IN WINDS IS
EXPECTED ON SATURDAY. DANGEROUS BOATING CONDITIONS AND SMALL CRAFT
ADVISORIES ARE EXPECTED TO CONTINUE THROUGH EARLY NEXT WEEK.

THE INCREASING WINDS AND BUILDING SEAS WILL BE FURTHER AGGRAVATED BY
ASTRONOMICAL HIGH TIDE OCCURRING THIS WEEKEND...WITH THE POTENTIAL
FOR ROUGH SURF AND BEACH EROSION. HIGH SURF ADVISORIES MAY BECOME
NECESSARY BY FRIDAY."


jo
Windy and damp Jo:


...THE BIGGER STORY WILL BE THE BREEZY/WINDY CONDITIONS.
NORTHEASTERLY WINDS WILL LIKELY REACH 20 MPH (SUSTAINED) ALONG THE
COAST...WITH GUSTS AS HIGH AS 25-30 MPH.

Just a little moisture:




Randrewl, that's not fair, you get rain and I get fog so bad they have warnings out!
Just kidding, know you need the rain as bad as we do. But the drive home this morning was hair raising.
Break out the umbrella's. How about that GFDL for accuracy.
I read there was some terrible fog this morning. Where are you Stormy?
Anyone have a good pic of 91C - particularly anything showing location and direction?
East side of Tampa
For anyone who is interested, The NASA's Earth Observatory put out a great articule called "Hurricane's: The Greatest Storms on Earth" Nov 1, 2006 by Steve Graham and Holli Riebeek.
mornin everybody! :)






is it over yet????
good morning all

looks like 93L is just sitting and spinning. This is the time of yr when a system in that area can come up to the ENE or NE and there is a front making its way in that direction.
The direction of the upper level cloud flow is often a good indicator of the direction of steering winds once a system starts to move. This one will likely do one of 3 things, go ashore near to its current location, move off to the NE or ENE or simply sit and spin itself out.
Anything I missed ? LOL
veracruz has west winds, and Coatzacoalcos has north winds at the surface......
it does look stationary atm.....
thelmores

where are those two cities ?
Corozal in extreme N Belize has NNE winds. Every where else in Belize says " calm " with a pressure of 29.85 and falling
Link
thelmores
Veracruz Mexico has W winds.
Are you saying that is an indicator that the front is on the way E towards 93L ?
GFDL had the track, and said sit and spin itself out at that time so that is what I tend think also. GFDL has performed remarkably this year.
563. MTJax
Stick with CLP5 early. NW, then N, use GFS ensemble for the later days with this moving NE to E