Hurricane Rina

[Somerset Squall]

Invest 96L in the western Caribbean has become the eighteenth tropical depression of the Atlantic season. Convection has persisted near the well defined LLC. Intensity is currently 30kts. Moderate shear should keep 18L in check over the next couple of days and only allow for slow intensification. Models favour a continued northerly motion followed by a split. Some models are going for a turn westwards into central America and others are favouring continued northerly motion into the southeast Gulf Of Mexico. 18L is worth watching because if the shear eases, the system could become stronger than the 50kts currently forecast by the NHC.

[Cookie]

[knocker]

Latest sat..

[Paranoid]

Been upgraded to TS Rina overnight, currently forecast to make it to Cat 1 just east of the Yucutan before heading into the GOM.

[Konstantinos]

Tropical Storm Rina is strengthening a bit over the western Caribbean Sea, centered at midday about 190 miles southwest of Grand Cayman Island. Rina may become a Category 1 hurricane by Tuesday Night. The storm is moving to the northwest, and a turn to the west-northwest is expected later today. The government of Honduras has discontinued the Tropical Storm Watch for that country. Interests in Belize, the east coast of the Yucatan Peninsula, and the adjacent islands should monitor the progress of Rina. For storm information specific to your area, please consult the products issued by your country's National Meteorological Service. Rina is not a threat to the United States at this time.

Source: NOAA NWS National Hurricane Center

[Gorky]

Already reached Hurricane strength as it appears to be rapidly intensifying. Now forecast to reach Major hurricane status as it approaches the Yucatan Peninsula.

[Somerset Squall]

Rina has just shown how the very high ocean heat content can win out over dry air. Excellent outflow has mixed out the dry air to the north of the hurricane, and an eye appears to be forming in the central dense overcast. Intensity has risen to 65kts. Rina has a much more symmetrical look this evening. Convection was previously lacking in the southern quadrant, but this is no longer a problem. Rina is over the warmest waters of the basin so the hurricane could rapidly intensify as it approaches the Yucatan Peninsula. Belize and adjacent countries should be very wary of Rina.

[Paranoid]

What's the shear forecast like for the region? Last i saw it was up to 60kts north of Cuba, which i imagine would shred any system regardless of organisation.

[summer blizzard]

Rina looking very good, a final offering from an interesting season.

[knocker]

HURRICANE RINA DISCUSSION NUMBER 6

NWS NATIONAL HURRICANE CENTER MIAMI FL AL182011

500 PM EDT MON OCT 24 2011

VISIBLE SATELLITE IMAGES SHOW SEVERAL BANDS OF DEEP CONVECTION

WRAPPING AROUND THE CENTER OF RINA AND A SMALL CENTRAL DENSE

OVERCAST FEATURE. THE HURRICANE HUNTER AIRCRAFT HAS NOT REPORTED

ANY STRONGER WINDS SINCE THEIR INITIAL PASS INTO THE CENTER JUST

BEFORE 1800 UTC...AND BASED ON THE EARLIER DATA THE INITIAL

INTENSITY WILL REMAIN 65 KT.

RINA WILL BE TRAVERSING VERY WARM WATER AND REMAIN IN A LOW SHEAR

ENVIRONMENT DURING THE NEXT COUPLE OF DAYS. THE ONLY NEGATIVE

FACTOR FOR INTENSIFICATION IS AN AREA OF DRY AIR TO THE NORTHWEST

OF THE CYCLONE. SO FAR...RINA HAS REMAINED WELL INSULATED FROM THE

DRY AIR AND THE OFFICIAL FORECAST ASSUMES THAT THE DRY AIR WILL NOT

REACH THE CORE DURING THE NEXT COUPLE OF DAYS. AFTER THAT...

SOUTHERLY SHEAR IS FORECAST TO INCREASE AND RINA IS ALSO EXPECTED

TO INTERACT WITH A FRONTAL BOUNDARY THAT MOVES INTO THE

SOUTHEASTERN GULF OF MEXICO NEAR THE END OF THE FORECAST PERIOD.

THE INTENSITY FORECAST IS VERY SIMILAR TO THE ONE ISSUED IN THE

SPECIAL ADVISORY AND IS NEAR THE GFDL AND HWRF GUIDANCE THROUGH 48

HOURS. AFTER THAT TIME...IT IS CLOSER TO A BLEND OF THE STATISTICAL

AND DYNAMICAL MODEL GUIDANCE. GIVEN THE RELATIVELY SMALL SIZE OF

THE HURRICANE...IT WOULD NOT BE SURPRISING TO SEE RAPID CHANGES

BOTH UP AND DOWN IN ITS INTENSITY.

THE AIRCRAFT FIXES SHOW THAT THE HURRICANE HAS SLOWED DOWN. A

BUILDING HIGH PRESSURE RIDGE OVER THE NORTHERN GULF OF MEXICO IS

EXPECTED TO STEER RINA WESTWARD DURING THE NEXT 24 TO 36 HOURS.

AS THE RIDGE SLIDES EASTWARD THE HURRICANE SHOULD TURN

NORTHWESTWARD...THEN NORTHWARD IN 2 TO 3 DAYS. AFTER THAT...THE

TRACK GUIDANCE BECOMES QUITE DIVERGENT WITH THE GFDL AND HWRF

TAKING THE CYCLONE NORTHEASTWARD...AND THE GFS SHOWING AN

EASTWARD OR EAST-SOUTHEASTWARD MOTION. FOR NOW...THE NHC FORECAST

REMAINS BETWEEN THESE TWO EXTREMES AND SHOWS A SLOW EAST-NORTHEAST

MOTION NEAR THE END OF THE PERIOD.

GIVEN THE EXTREMELY LARGE SPREAD IN THE GUIDANCE...AND THE POOR RUN

TO RUN CONSISTENCY...THERE IS MUCH LOWER THAN NORMAL CONFIDENCE IN

THE LONG-RANGE TRACK FORECAST OF RINA.

FORECAST POSITIONS AND MAX WINDS

INIT 24/2100Z 17.1N 83.1W 65 KT 75 MPH

12H 25/0600Z 17.2N 83.7W 75 KT 85 MPH

24H 25/1800Z 17.3N 84.4W 90 KT 105 MPH

36H 26/0600Z 17.6N 85.2W 100 KT 115 MPH

48H 26/1800Z 18.1N 86.0W 105 KT 120 MPH

72H 27/1800Z 19.8N 87.2W 95 KT 110 MPH

96H 28/1800Z 21.0N 87.0W 85 KT 100 MPH

120H 29/1800Z 21.5N 85.0W 75 KT 85 MPH

[Somerset Squall]

Rina looking very good, a final offering from an interesting season.

Mmmm, possibly, but watch 97L.

What's the shear forecast like for the region? Last i saw it was up to 60kts north of Cuba, which i imagine would shred any system regardless of organisation.

Shear is low in the region, and thus any dry air should not filter into the core and further intensification should take place. But as you say, shear is high north of Cuba and across the GOM, so Rina will be a goner if/when she ventures this far north.

[knocker]

[Somerset Squall]

Rina has maintained a solid CDO feature whilst intensifying. Intensity is now 85kts, making Rina a category 2 on the SS scale. Rina should become a major hurricane later tonight or tomorrow as it approaches the Yucatan Peninsula. Land interaction and increasing shear will induce a weakening trend beyond 36hrs as Rina curves northeastwards towards Cuba.

[Somerset Squall]

Rina's eye is now evident and clearing out. Intensity is now 90kts but I expect a faster rise in intensity soon. Rina may achieve cat 4.

[iand61]

We went on holiday to Playacar on the Yucatan in August.

One night we were talking about hurricanes in that area of the Carribean and the hotel staff i spoke to said that they had not had a direct hit for about 10 years. Looks like that run maybe just about to end.

[Konstantinos]

Hi all. I have a friend who lives in Cancun Mexico. She will send me photos and videos during Rina. When she sends me I will upload them here directly. I have the first two photos:

[knocker]

[Somerset Squall]

Rina peaked at 95kts yesterday but has since weakened considerably as it approaches the Yucatan coast thanks to increasing shear and dry air. Rina barely clings on to hurricane status this morning, with intensity now reduced to 65kts. Rina has a shrinking and increasingly rugged central dense overcast, and the eye has disappeared from satellite imagery. Further weakening should occur over the next day or two as shear continues to increase and Rina interacts with land. Rina will turn to the north over the next day or so but will then reverse course southwards as the storm becomes increasingly weak and shallow, and begins to be steered by northerly low level flow around the eastern side of a mid to low level ridge building over the Bay of Campeche.

[knocker]

SINCE THE VERTICAL SHEAR IS FORECAST TO GRADUALLY INCREASE...THE

MID-/UPPER-LEVEL CIRCULATION IS EXPECTED TO DECOUPLE FROM THE

LOW-LEVEL CIRCULATION AND LIFT OUT TO THE NORTHEAST WHILE THE

LOW-LEVEL CIRCULATION REMAINS BEHIND OVER THE NORTHWESTERN

CARIBBEAN SEA. THIS STRONG SHEAR PATTERN SHOULD CAUSE RINA TO

STEADILY WEAKEN THROUGHOUT THE FORECAST PERIOD...AND THE CYCLONE

COULD BECOME A TROPICAL DEPRESSION BY LATER TODAY OR EARLY

SATURDAY. RINA IS EXPECTED TO BECOME A REMNANT LOW OVER THE

NORTHWESTERN CARIBBEAN BY 48 HOURS...BUT WITH A SLIGHT CHANCE OF

REGENERATING INTO A TROPICAL CYCLONE IF IT DOES NOT GET ABSORBED

INTO THE BROAD LOW PRESSURE SYSTEM LOCATED EAST OF NICARAGUA.

[summer blizzard]

In the end an interesting but non-descript storm peaking as a strong category 2.

I was reading the observation of a guy from the USA who went chasing this (went when it was still forecast to hit as a major) and he did say that while weak (maximum sustained winds were 33KT with pressure of 996mb in the centre), much of the structure of the hurricane was still intact and that there was even a kind of eye feature in the centre as it stopped raining for 30 minutes (though clearly dying and not closed).