Tropical Cyclone Activity Report – Pacific / Indian Oceans

According to the CPHC, ANIMATION SHOWS THE LOW LEVEL CENTER LIKELY REMAINS JUST ALONG THE SOUTHERN EDGE OF DEEPEST CONVECTION…MAKING EARLIER FIX CONFIDENCE DEPENDENT ON A PINHOLE EYE FEATURE A GOOD BET.

IGNACIO DOES NOT HAVE THE SATELLITE PRESENTATION OF A HEALTHY TROPICAL SYSTEM. DEEP CONVECTION AND ALMOST ALL ASSOCIATED LAYERED CLOUDS HAVE BEEN DISPLACED NORTH AND NORTHEAST OF THE CENTER, BY SOUTHWEST WIND SHEAR RANGING FROM 11 TO 25 KNOTS.

THE NORTHWEST EDGE OF THE LAYERED CLOUD CANOPY IS BEGINNING TO MERGE WITH CLOUDS ASSOCIATED WITH A FRONTAL BOUNDARY. 

IGNACIO CONTINUES MOVING AT A STEADY RATE TOWARD THE NORTH NORTHWEST…OR 335 DEGREES AT 11 KNOTS. TRACK AND INTENSITY GUIDANCE REMAIN TIGHTLY CLUSTERED…AND FORECAST PHILOSOPHY HAS NOT CHANGED SINCE LAST EVENING.

THE FORECAST TRACK IS THEREFORE PRETTY MUCH UNCHANGED AS THIS SYSTEM MOVES INTO A WEAKNESS IN THE RIDGE TO ITS NORTH.

BETWEEN 36 AND 48 HOURS…WHATEVER IS LEFT OF THE CORE OF IGNACIO WILL BEGIN TO MERGE WITH THE COLD FRONT PRESSING IN FROM ITS WEST.

THE MID-LEVEL TROUGH SUPPORTING THE FRONT WILL THEN DRIVE IGNACIO FARTHER NORTHWARD AND STRENGTHENING WESTERLIES WILL CAUSE AN INCREASE IN FORWARD SPEED TOWARD THE NORTHEAST.

INSTEAD OF IMMEDIATELY DISSIPATING…IGNACIO WILL MAKE A COMPLETE TRANSITION TO AN EXTRATROPICAL STORM LOW AT 72 HOURS.

IGNACIO IS THEN FORECAST TO GRADUALLY WEAKEN AS IT RACES NORTHEASTWARD TOWARD THE MAINLAND…DISSIPATING BY DAY FIVE OVER BRITISH COLUMBIA. THE IGNACIO FORECAST TRACK…INTENSITY…AND WIND RADII FOR DAYS THREE AND FOUR…AND DISSIPATION ON DAY FIVE.

Maximum surface winds at the CPHC advisory #43 was 75 mph sustained winds

Hurricane 13E (Jimena) remains in the central Pacific…staying away from the Hawaiian Islands

This area is located about 650 miles east of Hilo, Hawaii…moving northwestward at about 5 mph.

According to the CPHC, JIMENA CONTINUES TO STRUGGLE IN AN INCREASINGLY HOSTILE ENVIRONMENT EARLY THIS MORNING. THERE IS NO EYE EVIDENT…AND DEEP CONVECTION IS CONFINED PRIMARILY IN A RELATIVELY SMALL AREA IN THE NORTHEASTERN SEMICIRCLE OF THE INNER CORE OF THE HURRICANE

. THE LATEST ESTIMATE OF ENVIRONMENTAL VERTICAL WIND SHEAR IN THE VICINITY OF JIMENA IS 16 KNOTS FROM 245 DEGREES AND 12 KNOTS FROM 285 DEGREES.

IN ADDITION TO WIND SHEAR BEING A LIKELY CULPRIT IN THE DEGRADATION OF JIMENA…WATER VAPOR IMAGERY STRONGLY SUGGESTS THAT VERY DRY AIR IS BEING ENTRAINED INTO THE SYSTEM. ALSO…EVEN THOUGH THE OUTFLOW ALOFT WAS RATHER IMPRESSIVE EARLIER TONIGHT…IT NOW APPEARS TO BE SHOWING SOME RESTRICTIONS IN THE WESTERN QUADRANT.

JIMENA REMAINS IN AN AREA OF WEAK STEERING…AND THE CURRENT MOTION IS 310/04 KNOTS. 

THIS WEAK STEERING WILL LIKELY CONTINUE THROUGH TONIGHT. FROM SATURDAY INTO SUNDAY…THE WEAK STEERING PATTERN WILL PERSIST AS A MID LEVEL RIDGE TO THE EAST BUILDS TO THE SOUTHEAST AND SOUTH OF JIMENA. THIS IS EXPECTED TO RESULT IN A SLIGHTLY FASTER MOTION TOWARD THE NORTH-NORTHWEST.

BY MONDAY AND TUESDAY…THE MID LEVEL RIDGING TO THE NORTH IS FORECAST TO STRENGTHEN…AND JIMENA WILL LIKELY TURN TOWARD THE WEST. THE LATEST FORECAST IS CLOSE TO THE PREVIOUS THROUGH 72 HOURS.

THE FORECAST TRACK IS NUDGED SLIGHTLY TO THE RIGHT COMPARED WITH THE PREVIOUS FORECAST ON DAYS 4 AND 5.  

NOTE THAT THE MODEL SPREAD IS FAIRLY SMALL THROUGH 72 HOURS…WITH A MUCH WIDER SPREAD ON DAYS 4 AND 5. THEREFORE…THERE REMAINS A GREAT DEAL OF UNCERTAINTY IN THE TRACK FORECAST AS THIS SYSTEM MOVES TO A POSITION NORTH-NORTHEAST OF THE MAIN HAWAIIAN ISLANDS.

THE LATEST INTENSITY FORECAST CONTINUES TO SHOW GRADUAL…BUT STEADY WEAKENING. THIS IS PRIMARILY DUE TO THE EFFECTS OF MODERATE WEST-SOUTHWEST TO WEST WIND SHEAR DURING THE NEXT 18-24 HOURS. BEYOND 24 HOURS…THE SHEAR STEADILY INCREASES…WHILE SEA SURFACE TEMPERATURES AND OCEAN HEAT CONTENT VALUES GRADUALLY DECREASE.

Maximum surface winds at the NHC advisory #36 was 85 mph sustained winds

Tropical Storm 14E (Kevin) remains active in the eastern Pacific…staying away from the Mexican coast 

This area is located about 360 miles west-southwest of the southern tip of Baja California…moving north at about 8 mph.

According to the NHC, Kevin’s cloud pattern consists of a large circular mass of very deep convection, with the low- to mid-level centers nearly co-located as of several hours. Since that time, satellite data indicate that the cyclone has begun the process of decoupling due to the 25 kt of south-southwesterly vertical wind shear affecting it. 

Even stronger shear associated with a potent mid- to upper-level trough to the northwest of Kevin should result in a complete separation of the cyclone’s low- to mid-level circulations within 24 hours, according to global models.

Substantially drier air behind the trough should also be entrained by the tropical cyclone, which should cause a collapse of deep convection during the next or so.

Global models depict Kevin becoming a remnant low in about 36 hours and show dissipation by 72 hours. The new intensity forecast shows faster weakening than the previous one, with remnant low status and dissipation also indicated sooner.

Based on fixes from a series of microwave passes overnight, this tropical cyclone has been moving a little east of due north, and the initial motion estimate is 010/07 knots.

Kevin should turn due north soon when the trough to its northwest sinks southward. As Kevin decouples during the next 24 hours, a deceleration is forecast by the model guidance. A bend in the track toward the northwest and west- northwest is also anticipated during this time, when Kevin meets the opposing flow around the low-level subtropical ridge over the eastern Pacific.

The new track forecast is on the right side of the guidance envelope at first, primarily due to the north-northeasterly motion overnight but is shifted a bit southward once Kevin becomes a remnant low.

Maximum surface winds at the NHC advisory #16 was 60 mph sustained winds