Tropical Storm Kristy

[summer blizzard]

Yet another storm has formed in the East Pacific and is expected to reach Hurricane status within 48 hours.

ZCZC MIATCDEP2 ALL

TTAA00 KNHC DDHHMM

TROPICAL STORM KRISTY DISCUSSION NUMBER 2

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP122006

200 AM PDT WED AUG 30 2006

INFRARED SATELLITE IMAGERY INDICATES THAT TD-12E HAS BECOME BETTER

ORGANIZED AS A LARGE BURST OF DEEP CONVECTION HAS INCREASED AND

EXPANDED OVER THE LOW-LEVEL CENTER. SATELLITE INTENSITY ESTIMATES

ARE T2.5/35 KT FROM BOTH TAFB AND SAB...SO THE DEPRESSION HAS BEEN

UPGRADED TO TROPICAL STORM KRISTY.

THE INITIAL MOTION ESTIMATE IS AN UNCERTAIN 305/6...BASED ON A BLEND

OF INFRARED SATELLITE FIX POSITIONS AND EARLIER QUIKSCAT WIND DATA.

KRISTY IS EXPECTED TO MOVE GENERALLY WEST-NORTHWESTWARD AT A SLOWER

THAN AVERAGE FORWARD SPEED OF 6-8 KT AROUND THE SOUTHERN PERIPHERY

OF THE SUBTROPICAL RIDGE AND TOWARD A BROAD WEAKNESS IN THE RIDGE

AXIS SITUATED BETWEEN 120-130W LONGITUDE. THE MID-LEVEL TROUGH

CREATING THE WEAKNESS IN THE RIDGE IS FORECAST TO SLOWLY LIFT OUT

TO THE NORTHEAST AND GRADUALLY ALLOW THE RIDGE TO BUILD WESTWARD TO

THE NORTH OF KRISTY. THE OFFICIAL FORECAST TRACK IS A LITTLE TO THE

LEFT OF THE PREVIOUS TRACK AND IS SIMILAR TO...BUT NORTH OF...THE

NHC MODEL CONSENSUS.

KRISTY IS FORECAST TO REMAIN OVER 28-29C SSTS AND IN A VERY LOW

VERTICAL SHEAR ENVIRONMENT OF LESS THAN 5 KT FOR THE NEXT 48

HOURS...SO AT LEAST STEADY STRENGTHENING SEEMS REASONABLE. GIVEN

THAT KRISTY IS A SMALL AND TIGHT CIRCULATION...IT IS POSSIBLE THAT

THE CYCLONE COULD INTENSIFY FASTER THAN THE CURRENT OFFICIAL

FORECAST IS INDICATING AND BECOME A HURRICANE IN 24 HOURS OR SO.

FORECAST POSITIONS AND MAX WINDS

INITIAL 30/0900Z 16.5N 114.7W 35 KT

12HR VT 30/1800Z 17.0N 115.4W 40 KT

24HR VT 31/0600Z 17.6N 116.4W 45 KT

36HR VT 31/1800Z 18.2N 117.6W 55 KT

48HR VT 01/0600Z 18.7N 118.8W 65 KT

72HR VT 02/0600Z 19.5N 121.0W 55 KT

96HR VT 03/0600Z 20.0N 123.5W 45 KT

120HR VT 04/0600Z 20.0N 126.0W 40 KT

$$

FORECASTER STEWART

NNNN

http://www.nrlmry.navy.mil/htdocs_dyn/tc_p...1145W.100pc.jpg

Well defined circulation, great banding, great outflow, expect this system to become a hurricane within 24 hours.

[parmenides3]

Everyone's been looking in the wrong place!

On a more serious note, is it possible that the reason that we are onto E-Pac system no. 12, and meanwhile the Caribbean/Gulf is relatively benign, has to do with the extra 'lift' in convection/moisture content caused by crossing the Isthmus? Or are they completely unconnected?

P

[summer blizzard]

I think that the main reason for the way the two hurricane seasons have gone is El Nino, El Nino causes the sub-Tropical Jet Stream to be more active in the Atlantic, and as a result upper lows have effectively built a barrier west of 80W, any storm that gets past gets sheared, while in the Pacific, this has led to a combination of very hot water and an unstable environment, effectively doing what the Atantic 2005 hurricane season did.

[Somerset Squall]

Just when the NHC thought Kristy was dissapating, she has restrengthened yet again to a tropical storm. This storm has survived amazing amounts of shear and was forecasted to dissapate two days ago! Amazing storm, if not in intensity, in it's fighting power.

Seems NHC are equally baffled:

000

WTPZ42 KNHC 051430

TCDEP2

TROPICAL STORM KRISTY DISCUSSION NUMBER 27

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP122006

800 AM PDT TUE SEP 05 2006

JUST WHEN WE THINK THAT KRISTY IS DONE FOR... A STRONG BURST OF

CONVECTION NEAR THE CENTER HAS PERSISTED FOR THE LAST SEVERAL

HOURS. DVORAK T-NUMBERS NOW SUPPORT TROPICAL STORM STRENGTH... AND

KRISTY HAS BEEN UPGRADED TO BE A TROPICAL STORM... AGAIN. THE

SYSTEM APPEARS TO HAVE SURVIVED THE STRONG EASTERLY SHEAR...

RELAXING SOMEWHAT DUE TO AN INVERTED UPPER-LEVEL TROUGH TO THE

EAST... BUT THE OVERALL ENVIRONMENT AROUND THE STORM IS PRETTY

MARGINAL FOR ANY SIGNIFICANT STRENGTHENING. A STABLE STRATOCUMULUS

CLOUD LAYER IS TRYING TO WRAP INTO THE STORM'S CIRCULATION AND

SHIPS DIAGNOSES RATHER DRY CONDITIONS IN THE MIDDLE TO UPPER LEVELS

BEYOND 48 HOURS. HOWEVER... SSTS STAY NEAR OR ABOVE 26C FOR THE

PERIOD... AND SHEAR SHOULD REMAIN LIGHT FOR AT LEAST THE NEXT FEW

DAYS. THEREFORE... KRISTY ISN'T EXPECT TO FLOURISH BUT...

UNFORTUNATELY... DISSIPATION IS NO LONGER ANTICIPATED. GLOBAL

MODELS GENERALLY HOLD ON TO THE SYSTEM THROUGHOUT 5 DAYS... AND SO

DOES THE OFFICIAL FORECAST.

THE CYCLONE CONTINUES TO ACCELERATE TOWARD THE WEST... 275/7. A

DEVELOPING RIDGE TO THE NORTH SHOULD PUSH KRISTY WEST TO

WEST-NORTHWESTWARD AT A FASTER RATE FOR THE FIRST 24-36 HOURS.

THEREAFTER... THE RIDGE COULD STRENGTHEN A LITTLE... CAUSING THE

STORM TO FOLLOW A WESTWARD COURSE FOR THE REMAINDER OF THE

FORECAST. THE OFFICIAL FORECAST IS A LITTLE FARTHER NORTH THAN

PREVIOUS.. BUT NOT AS FAR TO THE NORTH AS THE MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 05/1500Z 16.4N 121.5W 35 KT

12HR VT 06/0000Z 16.7N 123.0W 35 KT

24HR VT 06/1200Z 17.1N 125.1W 35 KT

36HR VT 07/0000Z 17.5N 127.0W 35 KT

48HR VT 07/1200Z 17.5N 128.5W 35 KT

72HR VT 08/1200Z 17.5N 131.5W 35 KT

96HR VT 09/1200Z 17.5N 134.5W 35 KT

120HR VT 10/1200Z 17.5N 137.5W 35 KT

$$

FORECASTER BLAKE/STEWART