000
AXPZ20 KNHC 270331
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE MAY 27 2008

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...TROPICAL WAVES...

NONE.

...ITCZ...

INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 11N85W TO 06N106W 
TO 12N132W TO 09N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED WITHIN 180 NM EITHER SIDE OF LINE FROM 
06N80W TO 07N108W. 

...DISCUSSION...

AN UPPER SHORTWAVE TROUGH DOMINATES THE SUBTROPICAL PORTION N OF 
23N WITH MEAN AXIS ALONG 125W. A TROPICAL UPPER ANTICYCLONE IS 
NEAR 16N131W WITH A SHORTWAVE RIDGE EXTENDING NE TO A CREST NEAR 
19N121W BUT THIS RIDGE APPEARS TO BE ERODING AS THE UPPER TROUGH 
TO THE N DIGS FURTHER SE WITH TIME. A SECOND UPPER ANTICYCLONE 
IS NEAR 24N103W WITH A RIDGE EXTENDING SW TO A SHARP CREST NEAR 
17N111W. A UPPER TROUGH DOMINATES THE CARIBBEAN BETWEEN 90W AND 
70W. THE REMAINDER OF THE TROPICAL PAC TO THE S OF THIS 
CARIBBEAN TROUGH IS DOMINATED BY WEAK RIDGING FROM THE 
ANTICYCLONE NEAR 24N103W. 

UPPER DIFFLUENCE IS ENHANCING CONVECTION OVER THE AREA FROM 15N 
TO 5N BETWEEN 74W AND 108W. THE RESULTANT DEBRIS MOISTURE 
REMAINS S OF 16N AS THE DRY UPPER AIR ACCOMPANYING THE CARIBBEAN 
TROUGH SEEMS TO EVAPORATE THE MOISTURE. SOME OF THIS MOISTURE 
DOES SPREAD S OF THE EQ BETWEEN 77W AND 120W. SOME UPPER 
MOISTURE IS MOVING INTO THE NW PORTION TO THE N OF LINE TO THE N 
OF 26N W OF 123W WITH A NARROW PLUME CONTINUING E TO EXTREME SW 
CALIFORNIA. ELSEWHERE THE UPPER LEVELS APPEAR VERY DRY AND 
SUPPRESSES CONVECTION ALONG THE ITCZ BETWEEN 117W AND 148W.  

AT THE SURFACE A RIDGE EXTENDS INTO THE AREA FROM 32N142W TO 
16N120W. NORTHERLY SWELLS TO 9 FEET CONTINUE OVER THE AREA FROM 
10N TO 20N W OF 125W BUT ARE SUBSIDING AND SHOULD BE LESS THAN 8 
FEET BY EARLY WED. NW WINDS ALONG THE NORTHERN BAJA PENINSULA 
WILL SPREAD S ALONG THE ENTIRE PENINSULA BY THU WITH NW WINDS 
ALSO INCREASING TO 20 KT OVER THE SOUTHERN GULF OF CALIFORNIA 
THU.  

A LOW LEVEL TROUGH EXTENDS WNW FROM COSTA RICA TO NEAR 16N103W 
WITH SEVERAL CYCLONIC SWIRLS NOTED ALONG THE TROUGH AXIS. A 
SHIP REPORT FROM SHIP DDFD2 INDICATES THAT ONE CYCLONIC SWIRL 
NEAR 11N89W IS AT THE SURFACE WITH A PRESSURE OF ABOUT 1005 MB. 
ONLY A FEW CONVECTIVE CLUSTERS ARE CURRENTLY NOTED NEAR THE 
SWIRL. MODEL GUIDANCE CONTINUES TO SUGGEST THAT BROAD LOW 
PRESSURE SHOULD PERSIST IN THIS AREA FOR THE NEXT FEW DAYS AND 
THE UPPER PATTERN DESCRIBED ABOVE IS ALSO NOT EXPECTED TO CHANGE 
DURING THAT TIME. THEREFORE LITTLE MOVEMENT IS NOTED FOR THIS 
LOW PRESSURE ON THE MARINE TEXT AND GRAPHICAL PRODUCTS THROUGH 
72 HOURS. HOWEVER TO THE S OF THIS LOW PRESSURE AND THE TROUGH 
THE GRADIENT IS ALREADY AT 20 TO 25 KT AND THESE CONDITIONS 
EXPECTED TO PERSIST THROUGH 72 HOURS BUT SPREAD E TO ALONG 79W 
BY 48 HOURS. 

$$
NELSON