000
AXPZ20 KNHC 271604
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI AUG 27 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...SPECIAL FEATURES...

AT 27/1500 UTC...

HURRICANE FRANK IS CENTERED NEAR 18.8N 112.0W MOVING WNW OR 300 
DEG AT 5 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 987 MB. 
MAXIMUM SUSTAINED WINDS ARE 65 KT WITH GUSTS TO 80 KT. TROPICAL 
STORM FORCE WINDS EXTEND OUTWARD UP TO 70 NM FROM THE CENTER. 12 
FT SEAS EXTEND OUTWARD UP TO 240 NM SE OF THE CENTER. SEE LATEST 
NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/ WTPZ24 
KNHC FOR MORE DETAILS. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WITHIN 120 NM SEMICIRCLE.

...TROPICAL WAVES...

TROPICAL WAVE N OF 09N ALONG 89W MOVING W 10-15 KT. SCATTERED 
MODERATE CONVECTION SE OF THE COAST OF NICARAGUA AND EL SALVADOR 
ALONG THE WAVE AXIS BETWEEN 10N AND 13N.    

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 08N82W 
TO 08N104W...THEN RESUMES NEAR 14N113W TO 11N118W TO 12N129W TO 
09N140W. ISOLATED MODERATE CONVECTION WITHIN 90 NM S OF THE AXIS 
BETWEEN 82W AND 90W. 

...DISCUSSION...

ALOFT...A RIDGE EXTENDS WSW FROM NW MEXICO ACROSS THE CENTRAL 
GULF OF CALIFORNIA THROUGH AN ANTICYCLONE CENTERED NEAR 24N128W 
TO BEYOND 23N140W. UPPER LEVEL DIFFLUENCE FROM THE RIDGE IS 
ENHANCING DIURNAL CONVECTION NEAR THE GULF OF CALIFORNIA S OF 
29N. FRANK IS EMBEDDED IN A WEAK UPPER TROUGH THAT EXTENDS FROM 
FROM 24N108W TO 14N116W. INCREASING VERTICAL SHEAR AND COOLER 
SEA SURFACE TEMPERATURES ARE EXPECTED TO CAUSE FRANK TO WEAKEN 
AND LOSE ITS DEEP CONVECTION OVER THE NEXT TWO DAYS. WATER VAPOR 
IMAGERY SHOWS MODERATE SUBSIDENCE AND DRIER AIR ALOFT OVER A 
LARGE PORTION OF THE AREA NW OF A LINE FROM 28N111W TO 12N140W. 

SURFACE...A WEAK RIDGE EXTENDS SE FROM 30N140W TO NEAR 19N125W. 
LIES N OF 22N W OF 125W. NE WINDS WILL INCREASE TO 20 KT TONIGHT 
AND SAT AS PRES GRADIENT BUILDS OVER THE NW PART OF THE AREA. 
FRANK AND ITS ASSOCIATED WEATHER EFFECTS DOMINATE SYNOPTIC THE 
ENVIRONMENT FROM 13N TO 23N BETWEEN 108W AND 116W. SCATTEROMETER 
DATA SHOWS AREA OF S WINDS CONTRACTING S OF 8N TO E OF 105W... 
AND WEAK W WINDS N OF 8N E OF 104W. 

MARINE...OUTSIDE OF SWELLS GENERATED BY FRANK..ALTIMETRY SHOWS 8 
FT SEAS CONFINED TO A SMALLER AREA GENERALLY S OF 4N S OF THE 
HURRICANE. WW3 MODEL GUIDANCE SHOWS 8 TO 10 FT SEAS SPREADING S 
OF 32N BETWEEN 119W AND 130W TONIGHT THROUGH SAT NIGHT. A NEW 
ROUND OF CROSS-EQUATORIAL SWELL WILL BRING SEAS BACK TO 8 TO 9 
FT IN EASTERN AND CENTRAL WATERS S OF 7N BY SAT NIGHT.

$$
MUNDELL