000
AXPZ20 KNHC 212201
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU JUN 21 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 
2100 UTC.

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

THE MONSOON TROUGH PASSES THROUGH 09N84W TO 06N89W TO 09N96W.
IT RESUMES FROM THE 1010 MB LOW PRESSURE CENTER THAT IS NEAR
19N108W TO 10N120W AND 05N130W. THE ITCZ CONTINUES FROM 05N130W 
TO 03N137W TO 03N140W. CONVECTIVE PRECIPITATION...SCATTERED 
STRONG FROM 17N TO 18N BETWEEN 102W AND 104W...SCATTERED 
MODERATE ISOLATED STRONG FROM 02N TO 09N BETWEEN 80W AND 
92W...FROM 07N TO 14N BETWEEN 99W AND 103W...AND WITHIN 120 NM 
ON EITHER SIDE OF THE LINE FROM 08N120W TO 06N130W TO 04N140W.

...DISCUSSION...
THE MONSOON TROUGH IS ANCHORED BY A PERSISTENT AREA OF LOW 
PRESSURE...1010 MB...NOW NEAR 19N109W. SATELLITE IMAGERY SHOWS
A LOW LEVEL CYCLONIC CIRCULATION BECOMING MORE DIFFUSE AS IT 
ENTRAINS DRIER AIR THAT IS TO THE SOUTH OF THE SOUTHERN TIP
OF BAJA CALIFORNIA. ASCAT DATA SHOW A BROAD AREA OF MODERATE 
WEST-TO-SOUTHWEST WINDS THAT ARE TO THE SOUTH OF THE MONSOON
TROUGH BETWEEN 100W AND 120W...AND GENERALLY LIGHT SOUTH-TO-
SOUTHWEST WINDS THAT ARE TO THE EAST OF 100W.

THE SURFACE WIND SPEEDS ARE LESS THAN 20 KT ACROSS THE EASTERN 
PACIFIC OCEAN...EXCEPT FOR A SMALL AREA OF NORTHWESTERLY WINDS
AROUND 20 KNOTS THAT ARE TO THE WEST OF THE BAJA PENINSULA...
AND A NARROW RIBBON OF 15-20 KNOT SOUTH-TO-SOUTHWEST WINDS THAT
ARE IN THE GULF OF CALIFORNIA. THE COMPARATIVELY LIGHTER WINDS
ARE DUE TO A WEAK SURFACE PRESSURE GRADIENT THAT COVERS THE
ENTIRE REGION. THE COMBINED SEA HEIGHTS GENERALLY RANGE FROM
5 TO 6 FEET ACROSS THE BASIN...EXCEPT FROM 15N TO 20N BETWEEN 
106W AND 110W...WHERE SEA HEIGHTS ARE REACHING 8 FEET. 
CROSS-EQUATORIAL SOUTHERLY SWELL TO 7 FT EXTENDS ACROSS
THE DEEP TROPICS BETWEEN 100W AND 125W.

GLOBAL FORECAST MODEL GUIDANCE INDICATES THAT THE 1010 MB LOW
PRESSURE CENTER THAT IS NEAR THE WEST COAST OF MEXICO WILL 
REMAIN NEARLY STATIONARY DURING THE NEXT 24 TO 48 HOURS...AND
IT WILL WEAKEN STEADILY. MONSOON WINDS FROM THE WEST-TO-SOUTHWEST
WILL CONTINUE TO THE SOUTH OF THE TROUGH TO THE EAST OF 120W.
THE MONSOON WINDS WILL BECOME WEAKER STEADILY DURING THE NEXT
2 TO 3 DAYS...WHILE NORTHEASTERLY TRADE WINDS THAT ARE TO THE 
WEST OF 120W WILL REMAIN WEAKER THAN USUAL. EXPECT MOSTLY BENIGN 
MARINE CONDITIONS ACROSS THE ENTIRE REGION...WITH THE HIGHEST
WINDS AND SEAS TO THE WEST OF NORTHERN BAJA CALIFORNIA NEAR THE
COAST TO THE NORTH OF 27N. BENIGN CONDITIONS ARE LIKELY TO 
CONTINUE EARLY NEXT WEEK...WITH NO TROPICAL CYCLONES EXPECTED
TO DEVELOP.

$$
MT