000
AXPZ20 KNHC 082125
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN MAY 08 2011

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 07N78W TO 
06N95W TO 08N107W TO 07N125W TO 05N140W. NUMEROUS MODERATE AND 
SCATTERED STRONG CONVECTION FROM 04N TO 09N E OF 85W. SCATTERED 
MODERATE CONVECTION WITHIN 120 NM S OF THE AXIS BETWEEN 87W AND 
91W. SCATTERED MODERATE TO STRONG CONVECTION WITHIN 180 NM S AND 
120 NM N OF THE AXIS BETWEEN 112W AND 119W. SCATTERED MODERATE 
TO STRONG CONVECTION WITHIN 120 NM EITHER SIDE OF THE AXIS 
BETWEEN 126W AND 133W.

...DISCUSSION...

AN UPPER LEVEL ANTICYCLONE WITH AN ASSOCIATED 1029 MB SURFACE 
HIGH REMAIN STACKED WELL NE OF HAWAII NEAR 36N147W...TO THE WEST 
OF A SHARP UPPER TROUGH AND AN ASSOCIATED COLD FRONT DIGGING 
THROUGH THE U.S. WEST COAST. THIS TROUGH ENTERS THE AREA NEAR 
32N119W AND REACHES SW TO A CUT OFF UPPER LEVEL LOW CENTERED 
NEAR 24N140W. TO THE SE OF THIS TROUGH AND LOW...W TO SW FLOW 
ALOFT DOMINATES THE MAJORITY OF THE FORECAST WATERS N OF 10N AND 
W OF 105W. THESE WINDS ARE TRANSPORTING ABUNDANT MID TO UPPER 
LEVEL MOISTURE INTO AND ACROSS N CENTRAL MEXICO. UPPER LEVEL 
DIVERGENCE BETWEEN AN UPPER LEVEL TROUGH THAT EXTENDS FROM 
10N108W TO 01N116W AND AN UPPER LEVEL ANTICYCLONE OVER THE SW 
CARIBBEAN IS ENHANCING MODERATE TO STRONG CONVECTION ALONG THE 
ITCZ AS DESCRIBED IN THE PRECEDING ITCZ SECTION.

SURFACE RIDGING STRETCHES FROM NEAR 31N140W TO 14N107W. SHIP 
OBSERVATIONS ALONG THE W COAST OF THE BAJA CALIFORNIA PENINSULA 
CONTINUE TO REPORT 20 KT NW WINDS WITH 8-9 FT SEAS...WHERE THE 
PRES GRADIENT IS THE TIGHTEST BETWEEN THE RIDGING AND TROUGHING 
NE OF THE AREA. THESE WINDS WILL PERSIST DURING THE NEXT FEW 
DAYS AS THE SENSIBLE WEATHER PATTERN CHANGES LITTLE. 20 KT NE-E 
TRADES WITH SEAS TO 8 FT EXIST IN THE W CENTRAL WATERS FROM 08N 
TO 16N W OF 125W. THESE WINDS WILL SHRINK IN COVERAGE BY 48 
HOURS AS THE PRES GRADIENT SLACKENS IN THE AREA.

CROSS-EQUATORIAL MIXED SE AND SW SWELL IS OVER THE FAR S CENTRAL 
WATERS WITH SEAS BUILDING TO 9 FT IN 24 HOURS THEN DECAYING BACK 
TO 8 FT BY 48 HOURS WHILE THE AREA OF HIGHEST SEAS SHIFTS MORE 
TO THE W.

ELSEWHERE AT THE SURFACE...SEVERAL TROUGHS ARE EMBEDDED WITHIN 
THE ITCZ. SCATTERED SHOWERS ARE OCCURRING NEAR THE TROUGHS. 
LATEST ASCAT PASSES INDICATE THAT WINDS APPEAR TO BE CAPPED AT 
10-15 KT IN THE VICINITY OF THESE FEATURES AND NO SIGNIFICANT 
DEVELOPMENT OF THEM ARE ANTICIPATED AS THEY MARCH OFF TO THE W 
DURING THE NEXT FEW DAYS.

GULF OF CALIFORNIA...
MODEL DIFFERENCES REMAIN REGARDING THE CHANCE FOR STRONGER WINDS 
IN THE NORTHERN GULF OF CALIFORNIA. THE 12Z GFS STILL INDICATES 
A BRIEF WINDOW OF 20-25 KT WINDS N OF 29N WITH THE 12Z ECMWF 
SHOWING A FEW 20 KT BARBS. MEANWHILE...ALL OTHER GLOBAL AND 
REGIONAL MODELS KEEP WINDS JUST LESS THAN 20 KT. AT THE VERY 
LEAST EXPECT A BRIEF PULSE OF 20 KT SW WINDS N OF 29N TONIGHT AS 
A TROUGH DIGS INTO THE SW U.S. ALTHOUGH WILL REFRAIN FROM 
MENTIONING THIS IN THE HIGH SEAS FORECAST GIVEN THE SMALL AREAL 
EXTENT AND BRIEF TIMING OF THE POTENTIAL ADVISORY EVENT.

GULF OF PAPAGAYO...
BRIEF OVERNIGHT AND EARLY MORNING 20 KT NE-E PULSES REMAIN 
LIKELY DURING THE NEXT 48 HOURS DURING PEAK DRAINAGE FLOW.

$$
LEWITSKY