000
AXPZ20 KNHC 020218
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC THU JUL 02 2015

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM  
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0200 UTC. 
 
...TROPICAL WAVES...

TROPICAL WAVE FROM 08N TO 14N NEAR 98W/99W NEAR THE EASTERN END 
OF AN UPPER TROUGH EXTENDING EAST TO WEST ALONG 21N. NO 
SIGNIFICANT CONVECTION IS NOTED WITH THIS WAVE. 

TROPICAL WAVE FROM 08N TO 15N NEAR 106W/107W IS DISPLAYED 
RELATIVELY WELL IN THE LOWER TO MID LEVELS OF THE ATMOSPHERE 
BASED ON ANIMATED PRECIPITABLE WATER IMAGERY AND GOES DERIVED 
HIGH DENSITY WINDS...BUT SHOWS UP POORLY AT THE SURFACE BASED ON 
A PAIR OF RECENT SCATTEROMETER PASSES. NO SIGNIFICANT CONVECTION 
IS NOTED WITH THIS WAVE.

TROPICAL WAVE FROM 05N TO 14N ALONG 129W/130W IS EMBEDDED IN A 
LARGE AREA OF SHOWERS AND THUNDERSTORMS ALONG THE ITCZ RELATED 
TO UPPER LEVEL DIVERGENCE AND WEAK TRADE WIND CONVERGENCE. THE 
WAVE IS POORLY PRESENTED AT THE SURFACE AND LOWER LEVELS OF THE 
ATMOSPHERE. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

NO MONSOONAL CIRCULATION IS CURRENTLY EVIDENT. THE ITCZ EXTENDS 
FROM 07N95W TO 06N120W TO 09N130W TO BEYOND 10N140W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS NOTED WITHIN 180 NM N 
OF THE ITCZ AXIS...AND 270 NM S OF THE ITCZ AXIS BETWEEN 115W 
AND 135W.

...DISCUSSION...

N OF 15N E OF 120W...WEAK 1013 MB LOW PRES W OF THE AREA NEAR 
26N125W HAS INTERRUPTED THE SUBTROPICAL RIDGE OVER THE 
AREA...AND IS MAINTAINING A LIGHT PRESSURE PATTERN OVER THE 
REGION...AS NOTED IN RECENT SCATTEROMETER DATA...INCLUDING 
ANOMALOUS SE FLOW OFF THE BAJA CALIFORNIA COAST. THIS WAS 
CONFIRMED A SHIP OBSERVATION FROM EARLIER THIS MORNING. A PAIR 
OF EARLIER ALTIMETER PASSES INDICATED SEAS OF GENERALLY 3 TO 5 
FT OFF THE BAJA PENINSULA. THE SURFACE LOW IS RELATED TO AN 
UPPER LEVEL LOW IN THE SAME AREA WITH A SHARP UPPER TROUGH 
REACHING ACROSS THE SOUTHERN TIP OF THE BAJA PENINSULA TO CABO 
CORRIENTES. DRY SUBSIDENT FLOW WRAPPING INTO WEST AND SW SIDE OF 
THE UPPER LOW IS SUPPRESSING CONVECTION ACROSS THE REGION. 
FARTHER SOUTH...A PULSE OF STRONG GAP WINDS WILL OCCUR THROUGH 
THE GULF OF TEHUANTEPEC TONIGHT...BUT WILL END QUICKLY AND NOT 
RESULTS IN SEAS 8 FT OR HIGHER. LOOKING AHEAD...THE LOW WEST OF 
THE AREA WILL DRIFT FARTHER WEST ALLOWING THE SUBTROPICAL RIDGE 
TO BUILD NEAR 25N120W. A SURFACE TROUGH OVER NORTHERN BAJA 
CALIFORNIA NORTE RELATED TO AN UPPER IMPULSE N OF THE AREA WILL 
ALLOW STRONG WINDS OFF THE SOUTHERN COAST OF BAJA CALIFORNIA 
NORTE FRI NIGHT.

S OF 15N E OF 110W...AN EARLIER ASCAT PASS VERIFIED STRONG GAP 
WIND FLOW THROUGH THE GULF OF PAPAGAYO...RELATED TO STRONG TRADE 
WIND FLOW OVER THE SW CARIBBEAN. WIND CONVERGENCE ON THE LEADING 
EDGE OF THIS PLUME OF GAP WINDS WAS RESULTING IN A FEW SHOWERS 
AND THUNDERSTORMS ALONG A LINE FROM 07N85W TO 10N90W. AN EARLIER 
ALTIMETER PASS INDICATED SEAS TO 10 FT DOWNSTREAM OF THE 
PLUME...BUT THIS LIKELY MISSED THE AREA OF PEAK WAVE HEIGHTS 
WITHIN THE PLUME WHICH MAY HAVE BEEN IN EXCESS OF 11 FT. ANOTHER 
PULSE OF GAP WINDS THROUGH PAPAGAYO IS EXPECTED TONIGHT AS SHORT 
PERIOD SWELL FROM THE EARLIER PLUME PROPAGATES WEST AND 
SUBSIDES. SIMILARLY FRESH NORTHERLY GAP WIND FLOW WILL PERSIST 
INTO THE GULF OF PANAMA TONIGHT AND THU NIGHT. 

ELSEWHERE...AN UPPER LOW REMAINS CENTERED NEAR 27N125W MOVING 
WEST. DIVERGENCE ALOFT ON THE SOUTHERN PERIPHERY OF THE UPPER 
LOW AND ANTICYCLONIC FLOW ALOFT S OF 12N INTERACTING WITH WEAK 
TRADE WIND CONVERGENCE TO SUPPORT CLUSTERS OF SHOWERS AND 
THUNDERSTORMS ALONG THE ITCZ BETWEEN 115W AND 135W. AN AREA OF 
NE SWELL TO 8 FT IS NOTED ON AN EARLIER ALTIMETER FROM 10N TO 
15N W OF 136W. WINDS WERE 20 TO 25 KT EARLIER...RELATED TO A AN 
TROPICAL WAVE THAT MOVE THROUGH THE THE AREA YESTERDAY...BUT 
THESE WINDS APPEAR TO HAVE DIMINISHED AS NOTED IN A RECENT  
ASCAT PASS. THE SWELL IS EXPECTED TO SUBSIDE BELOW 8 FT 
ACCORDINGLY WITHIN THE NEXT 18 TO 24 HOURS. ONLY MODERATE TRADE 
WINDS ARE NOTED DUE TO A WEAKENED SUBTROPICAL RIDGE N OF THE 
AREA...DUE THE PRESENCE OF THE DEEP LAYER LOW. GLOBAL MODELS ARE 
COMING INTO BETTER AGREEMENT INDICATING THE DEVELOPMENT OF WEAK 
LOW PRES IN THE DEEP TROPICS FROM 10N TO 15N BETWEEN 130W AND 
135W STARTING THU NIGHT INTO FRI...SUPPORTING FRESH TO STRONG 
FLOW AND SEAS TO 8 FT BY LATE FRI NEAR THE LOW PRES. 
 
$$ 
CHRISTENSEN