Hurricane Genevieve

[James M]

We now have yet another system in the East Pacific: TD Eight-E and it is expected to become Genevieve within 12 hours.

000

WTPZ43 KNHC 211458

TCDEP3

TROPICAL DEPRESSION EIGHT-E DISCUSSION NUMBER 1

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP082008

800 AM PDT MON JUL 21 2008

THE STRONG TROPICAL WAVE THAT THE NHC HAS BEEN WATCHING FOR SEVERAL

DAYS HAS FINALLY OBTAINED ENOUGH ORGANIZED CONVECTION AND LOW-LEVEL

CIRCULATION TO BECOME A TROPICAL DEPRESSION. THIS SAME SYSTEM

ALMOST BECAME A TROPICAL DEPRESSION BEFORE MOVING INTO CENTRAL

AMERICA A FEW DAYS AGO. THE LOW-LEVEL CENTER APPEARS TO BE ON THE

SOUTHEASTERN SIDE OF BANDED DEEP CONVECTION FEATURES. THE INITIAL

INTENSITY IS 30 KT IN LINE WITH QUIKSCAT ESTIMATES. A SLOW

INCREASE IN WINDS IS INDICATED DURING THE NEXT DAY OR SO DUE TO

MODERATE EASTERLY SHEAR. HOWEVER...THE SYSTEM COULD INTENSIFY A

LITTLE FASTER THEREAFTER AND HAS A GOOD CHANCE TO BECOME A

HURRICANE BEFORE MOVING OVER THE COOLER WATERS IN 4 DAYS OR SO.

THE OFFICIAL FORECAST IS A BLEND OF THE SHIPS/LGEM MODELS.

HWRF/GFDL DO NOT INTENSIFY THIS SYSTEM ON THEIR CURRENT INTEGRATION

BUT HAVE INTENSIFIED IT QUITE A BIT BEFOREHAND.

THE BEST ESTIMATE OF INITIAL MOTION IS 280/12. A WEST OR

WEST-NORTHWEST TRACK IS FORECAST FOR THE NEXT SEVERAL DAYS DUE TO

MID-TROPOSPHERIC RIDGING OVER MEXICO. FOR THE FIRST ADVISORY...

GUIDANCE IS IN GOOD AGREEMENT ON THIS WEST-NORTHWESTWARD TRACK.

THE SYSTEM COULD SLOW A LITTLE IN A COUPLE OF DAYS AS A WEAKNESS IN

THE RIDGE COULD AFFECT THE DEPRESSION. THE OFFICIAL FORECAST LIES

JUST TO THE NORTH OF THE DYNAMICAL MODEL CONSENSUS.

FORECASTER BLAKE

Edited July 21, 2008 by James M

[Somerset Squall]

Indeed, another system to continue the very active start to the East Pacific season. Deepest convection is currently displaced to the west of the centre due to moderate easterly shear over the system, but this is expected to ease. TD08E has a few days over very warm waters so once that shear eases expect some good strengthening- the NHC have the system reaching hurricane strength and the conditions certainly support the system becoming a hurricane (if it does it will be the fourth already!). Cooler waters will weaken the system beyond 96hrs as the system moves generally west-northwestward.

[Somerset Squall]

TD08E has been upgraded to Tropical Storm Genevieve, with an initial intensity of 35kts. Most of the deep convection still remains to the west of the centre but there is some good banding features associated with the storm. Genevieve is still expected to become a hurricane but how strong it gets is largely dependant on how much the shear eases.

[Paranoid]

000

WTPZ33 KNHC 212046

TCPEP3

BULLETIN

TROPICAL STORM GENEVIEVE ADVISORY NUMBER 2

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP082008

200 PM PDT MON JUL 21 2008

...THE SEVENTH TROPICAL STORM OF THE YEAR FORMS SOUTH OF MEXICO...

AT 200 PM PDT...2100Z...THE CENTER OF TROPICAL STORM GENEVIEVE WAS

LOCATED NEAR LATITUDE 13.9 NORTH...LONGITUDE 102.6 WEST OR ABOUT 275

MILES...440 KM...SOUTHWEST OF ACAPULCO MEXICO AND ABOUT 370 MILES...

595 KM...SOUTH-SOUTHEAST OF MANZANILLO MEXICO.

GENEVIEVE IS MOVING TOWARD THE WEST NEAR 17 MPH...28 KM/HR...AND

A MOTION TOWARD THE WEST OR WEST-NORTHWEST WITH A DECREASE IN

FORWARD SPEED IS EXPECTED DURING THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER

GUSTS. STEADY STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 50 MILES...85 KM

FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB...29.65 INCHES.

REPEATING THE 200 PM PDT POSITION...13.9 N...102.6 W. MOVEMENT

TOWARD...WEST NEAR 17 MPH. MAXIMUM SUSTAINED WINDS...40 MPH.

MINIMUM CENTRAL PRESSURE...1004 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT

800 PM PDT.

$$

FORECASTER BLAKE

[Cookie]

[Somerset Squall]

Genevieve is intensifying, and is now at 50kts. Track forecast has shifted southwards and as a consequence:

THE CYCLONE MAY MISS MOST OF THE WATERS COOLED BY ELIDA

AND FAUSTO.

so continued intensification is expected. Genevieve is expected to become a hurricane within 36hrs. After peaking, cooler waters and elevated shear will induce a weakening trend.

[Somerset Squall]

Genevieve is having trouble intensifying. It strengthened to 55kts last night but since has only remained at this intensity. Shear is preventing convection wrapping fully around the centre thus Genevieve's intensification trend, for now, has halted. It's central dense overcast feature isn't looking as impressive as yesterday and the time period for Genevieve to become a hurricane is closing in. The storm will remain over warm waters on the general west-northwest track for another good 48hrs but even stronger shear is poised to affect the system beyond 24hrs. Eventually, the waters will cool and shear will remain strong, and Genevieve is expected to be a weak tropical storm by the end of the forecast period (120hrs). The less Genevieve intensifies now, the less time those particularly unfavourable conditions will take to dissipate the storm.

[Somerset Squall]

Genevieve has weakened this afternoon, to 50kts. Continued shear is hampering development and the NHC say that Genevieve is moving over a cool eddy of water created by Fausto. It's touch and go whether Genevieve becomes a hurricane now, but intensification is expected in the near term as shear eases and Genevieve moves away from the eddy into warmer waters. Beyond 36hrs, shear increases again and sea temps shelve off, which will induce slow weakening.

[Cookie]

thanks for the updates

[Somerset Squall]

This morning, Genevieve moved over warmer waters, shear eased, and moisture remained plentiful. However, Genevieve still weakened, down to 45kts. Judging by satellite imagery, Genevieve may finally have responded to the more favourable conditions, with an eye developing in the central dense overcast. We'll have to wait and see what NHC says in the later update.

[Somerset Squall]

As I thought, Genevieve has finally responded to the more favourable conditions and has attained hurricane status, with an intensity of 65kts. There is scope for a little more intensification in the near term due to the the fact waters are warm and shear is low, however, beyond 24hrs the waters cool and easterly shear increases which will slowly weaken Hurricane Genevieve.

Interesting notes in the discussion for Genevieve:

GENEVIEVE IS UPGRADED TO A

HURRICANE WITH 65 KT WINDS...THE FOURTH OF THE EASTERN PACIFIC

HURRICANE SEASON. THIS FORMATION IS ABOUT TWO WEEKS AHEAD OF THE

MEAN FOURTH HURRICANE DATE OF 10 AUGUST IN THE EASTERN PACIFIC...

AND 2008 ALREADY HAS HAD AS MANY HURRICANES AS THE ENTIRE 2007

SEASON.

Shows how quiet 2007 was, and how active and above average 2008 has been for the East Pacific so far. Will the forecast for a slightly below average season go pear shaped?

Image showing the better looking Genevieve (oh err )

[Somerset Squall]

The last advisory has been issued for Genevieve as the circulation centre has been deviod of convection for 18hrs now. The remnant low will continue westwards over cool water and regeneration is not expected.

[Cookie]

thanks for all the updates as ever