000
AXPZ20 KNHC 172149
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI AUG 17 2012
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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2145 UTC.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...MONSOON
TROUGH FROM 09N83W TO 10N92W THEN RESUMES FROM 15N96W TO LOW
PRES 1009 MB AT 10N101W TO 09N110W. AXIS RESUMES AGAIN FROM
14N121W TO BEYOND 10N140W. NUMEROUS MODERATE SCATTERED STRONG
CONVECTION WITHIN 150 NM S OF AXIS E OF 91W AND WITHIN 60 NM
BOTH SIDES OF AXIS FROM 94W TO 98W. SCATTERED MODERATE ISOLATED
STRONG CONVECTION WITHIN 120 NM S OF AXIS FROM 103W TO 130W.
...DISCUSSION...
BROAD MID TO UPPER LEVEL ANTICYCLONE OVER NORTHWESTERN MEXICO
ADVECTS ABUNDANT MOISTURE INTO E PAC JUST E OF 120W N OF 13N BUT
ALSO BRINGS MODERATE TO STRONG WIND SHEAR ALOFT OVER REMNANTS OF
HECTOR. SECOND MID TO UPPER LEVEL ANTICYCLONE...JUST OVER
TROPICAL STORM HELENE IN SW BAY OF CAMPECHE...CONTRIBUTES
SIMILAR ADVECTION OVER 1009 MB LOW PRES AT 10N101W. WEAK UPPER
LEVEL TROUGH FROM 19N105W TO 06N116W SPLIT ANTICYCLONES AND
ALLOWS DIVERGENT FLOW ALOFT TO ENHANCE SCATTERED MODERATE
CONVECTION OVER MONSOON TROUGH W OF 1009 MB LOW PRES. AIR MASS
REMAINS VERY DRY N OF MONSOON TROUGH W OF 120W AS SURFACE HIGH
PRES PROMOTES MODERATE SUBSIDENCE.
...ELSEWHERE AT THE LOWER LEVELS...
FRESH SW WINDS IN SE QUADRANT TO REMNANTS OF HECTOR FORCE
EXISTING 8-9 FT SWELLS UNTO SOUTHERN PORTIONS OF GULF OF
CALIFORNIA WITH POSSIBILITY OF FUNNELING GROWING WAVES FARTHER
UP NORTH. SCATTERED...BUT DIMINISHING...CONVECTION MAY PRODUCE
TEMPORARY DETERIORATION OF MARINE CONDITIONS. HEAVY RAINS STILL
PROBABLE...PARTICULARLY OVER HIGH TERRAIN IN SONORA AND BAJA
CALIFORNIA TONIGHT AND SAT.
LOW PRES 1009 MB AT 10N101W REMAINS UNDER OVERALL ADVERSE
ENVIRONMENT WITH MODERATE TO STRONG WIND SHEAR THAT PRECLUDES
DEVELOPMENT. GLOBAL MODEL SOLUTIONS WEAKEN W DRIFTING SYSTEM
ALTHOUGH KEEPS AREA PRESSURES LOWER THAN NORMAL.
CROSS EQUATORIAL LONG PERIOD S SWELL PROPAGATING ALONG PAC COAST
BRING SEAS TO 10 FT AS FAR N AS 18N IS EXPECTED TO SUBSIDE
TONIGHT AND SAT.
$$
WALLY BARNES