000
AXPZ20 KNHC 280329
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON MAY 28 2007

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.

...SPECIAL FEATURES...

TROPICAL DEPRESSION ONE-E AT 13.0N 111.7W AT 2100 UTC WITH PRES 
OF 1007 MB MOVING W OR 270 DEG AT 4 KT. NUMEROUS STRONG 
CONVECTION HAS FLARED 30 NM OVER E SEMICIRCLE AND WITHIN 90 NM 
OVER W SEMICIRCLE OF CENTER. FAVORABLE WATER TEMPERATURES AND 
THE LIGHT ENVIRONMENTAL SHEAR SUPPORT THE FORECAST FOR CONTINUED 
SLOW DEVELOPMENT TO A TROPICAL STORM. 

...ITCZ...

INTERTROPICAL CONVERGENCE ZONE AXIS 15N92W 7N117W 8N140W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 150 NM EITHER SIDE OF 
LINE 14N92W 10N100W 12N106W 8N117W...AND WITHIN 30 NM OF 7N139W.

...DISCUSSION...

A WELL DEFINED UPPER ANTICYCLONE IS ANCHORED NEAR 14.5N116W. ITS 
ENVELOPE OF ANTICYCLONIC FLOW DOMINATES MOST OF THE DISCUSSION 
AREA N OF THE ITCZ AND W OF 112W WITH THE RIDGE CRESTING ALONG 
POINTS 20N140W 30N125W 24N111W. AN UPPER TROUGH IS OBSERVED NW 
OF THE RIDGE ALONG 32N123W 27N136W 26N140W. UPPER MOISTURE IS
INDICATED NW OF THE TROUGH AND ALONG A PLUME WITHIN 75 NM EITHER 
SIDE OF LINE 17N140W 26N128W. THE RIDGE SUPPRESSES CONVECTION 
ALONG THE ITCZ BETWEEN 130W AND 139W BUT ENHANCES ITCZ 
CONVECTION BETWEEN 121W AND 103W. SOME OF THE RESULTANT DEBRIS 
MOISTURE IS ADVECTED S ACROSS THE EQUATOR BETWEEN 100W AND 122W.
SOME OF THE MOISTURE SPREADS N BUT EVAPORATES IN THE UPPER DRY 
AIR ALONG 13N.  

AN UPPER TROUGH EXTENDS S ACROSS OLD MEXICO AND OVER THE E PAC 
ALONG 24N99W 18N99W 14N198W. ANOTHER UPPER ANTICYCLONE IS NEAR 
12N105W WITH A RIDGE E TO NEAR 13N83W ENHANCING CONVECTION NEAR 
11N99W. THE MODELS ARE KEYING ON THIS CONVECTION AND DEVELOPING 
LOW PRES IN THIS AREA OVER THE NEXT 24 HOURS. 

AT THE SURFACE...
WEAK HIGH PRES CENTER 1025 MB AT 34N134W HAS RIDGE EXTENDING SE 
TO NEAR 23N111W. 

$$
NELSON