000
AXPZ20 KNHC 211517
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU JUN 21 2007

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.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 94W FROM 4N TO 15N MOVING W 10 KT. AN AREA 
OF CONVECTION HAS DEVELOPED IN THE GULF OF TEHUANTEPEC REGION.  
THIS CONVECTION MAY BE ASSOCIATED WITH THE WAVE AN FLOW THROUGH 
THE ISTHMUS OF TEHUANTEPEC. A SMALL AREA OF ENHANCED CONVECTION 
IS LOCATED IN THE ITCZ REGION. SATELLITE IMAGERY PRESENTS NO 
CLEAR CIRCULATION.

TROPICAL WAVE ALONG 106W FROM 5N TO 16N MOVING W 10 KT. 
THE WAVE AXIS LIES W OF A LARGE CLUSTER OF DEEP CONVECTION IN 
THE ITCZ REGION. THE CONVECTION EXTENDS 360 NM EAST OF THE WAVE 
AXIS. THE CONVECTION SHOWS SLIGHT SIGNS OF ORGANIZATION BUT 
BEING WITHIN THE ITCZ THIS FEATURE MAY NOT PERSIST AS AN 
ORGANIZED CIRCULATION.

TROPICAL WAVE ALONG 125W FROM 4N TO 15N MOVING W 10 KT.
THERE IS NO ASSOCIATED CONVECTION AND NO ORGANIZATION TO THE 
CLOUD PATTERN.

TROPICAL WAVE ALONG 138W FROM 3N TO 13N MOVING W 10 KT. THE WAVE 
IS ASSOCIATED WITH A CLUSTER OF CONVECTION WITHIN THE ITCZ BUT 
OTHERWISE HAS NO NOTICEABLE SIGNATURE.

..ITCZ...

ITCZ AXIS IS CENTERED ALONG THE LINE...6N77W 7N105W 8N115W 
7N140W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM OF THE 
POINT 9N86.4W. SCATTERED MODERATE WITH ISOLATED STRONG 
CONVECTION IS WITHIN 75 NM OF THE POINT 7.7N102.6W.

OTHER SIGNIFICANT CONVECTION...SCATTERED MODERATE TO STRONG 
CONVECTION IS WITHIN 75 NM OF THE POINT 14.9N97.1W. SCATTERED 
MODERATE TO STRONG CONVECTION IS WITHIN 60 NM OF THE POINT 
15.5N99.4W.

...DISCUSSION...

MIDDLE AND UPPER LEVEL TROUGH IS WEST OF A LINE THROUGH 32N130W 
TO A MID LEVEL WEAK CYCLONIC CIRCULATION CENTER NEAR 17N132W AND 
TO 10N140W.  THE AREA IS CLOUD FREE AND DRY IN THE MIDDLE AND 
UPPER LEVELS WITH ONLY A SMALL AREA OF BROKEN UPPER CLOUDS TO 
THE EAST AND NORTH OF THE WEAK CIRCULATION CENTER. 

A SHORTWAVE MIDDLE AND UPPER FEATURE IS OVER WESTERN MEXICO. AN 
ASSOCIATED CYCLONIC CIRCULATION CENTER IS NEAR 25N109W WITH A 
WAVE AXIS TO 24N105W 20N105W. CLOUDINESS AND SHOWERS AND 
THUNDERSTORMS ARE ASSOCIATED WITH THIS SYSTEM INLAND OVER THE 
MOUNTAINS REGIONS.

ANOTHER TROUGH AFFECTS THE AREA AND EXTENDS FROM THE YUCATAN 
PENINSULA ACROSS GUATEMALA AND SOUTHERN MEXICO AND OVER THE 
PACIFIC NORTH OF THE ITCZ FROM 90W TO 100W.  A COUPLE OF AREAS 
OF ENHANCED CONVECTION ARE NEAR THE PERIPHERY OF THIS SYSTEM 
INCLUDING THE AREA NEAR THE GULF OF TEHUANTEPEC.

REMAINDER OF THE AREA IS COVERED BY ANTICYCLONIC FLOW. AN AREA 
OF VERY DRY AND CLOUD FREE AIR IS NORTH OF 15N BETWEEN THE 
TROUGH OVER WESTERN MEXICO AND THE CLOUDS ASSOCIATED WITH THE 
WEAK CYCLONIC CIRCULATION WHICH ARE OBSERVED TO BE WEST OF ABOUT 
128W.

UPPER LEVEL MOISTURE WITH EMBEDDED AREAS OF MULTI LEVEL 
CLOUDINESS ARE NORTH OF THE ITCZ EAST OF A LINE 20N105W TO 
15N115W TO THE ITCZ NEAR 120W. 

OVERCAST STRATOCUMULUS ARE OBSERVED NORTHWEST OF A LINE 30N115W 
20N120W 13N140W. BROKEN STRATOCUMULUS ARE ELSEWHERE WEST OF 110W 
NORTH OF 10N.

WEAK SURFACE RIDGE IS NORTH OF 15N WEST OF 110W. ELSEWHERE BROAD 
SURFACE TROUGH IS ANALYZED.

$$
LL