000
AXPZ20 KNHC 060920
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI JUN 06 2008

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 07N77W TO 10N90W TO 08N120W TO 
03N140W. SCATTERED MODERATE TO STRONG CONVECTION FROM 03N TO 11N 
BETWEEN 81W AND 88W. NUMEROUS MODERATE SCATTERED STRONG FROM 08N 
TO 12N BETWEEN 92W AND 111W.

...DISCUSSION...

A NEARLY ZONAL POLAR JET IS LOCATED WELL N OF THE AREA STREAMING 
ACROSS THE N PACIFIC INTO THE COAST OF OREGON THEN DIGGING INTO 
A SHARP SHORTWAVE TROUGH OVER THE CENTRAL UNITED STATES. A LARGE 
UPPER LEVEL CYCLONIC GYRE LIES W OF 125W WITH THE MAIN UPPER LOW 
CENTERED JUST N OF HAWAII NEAR 22N154W. NO FEATURE DOMINATES THE 
PATTERN OVER THE FAR EASTERN PACIFIC.

E OF 110W...
WATER VAPOR IMAGERY SHOWS THAT 110W SEPARATES DEEP MOISTURE NEAR 
MESOAMERICA FROM A MUCH DRIER AIR MASS FARTHER W. NO MAJOR 
SYNOPTIC FEATURES DOMINATE THE REGION BUT IN GENERAL BROAD 
MID/UPPER LEVEL RIDGING EXTENDS FROM THE SE U.S. INTO THE 
TROPICAL E PACIFIC. ON SMALLER SCALES...AN UPPER RIDGE AXIS LIES 
ACROSS CENTRAL MEXICO ALONG 23N WHILE A CYCLONIC SHEAR AXIS 
EXTENDS FROM THE WESTERN GULF OF MEXICO TO 18N110W WITH A SMALL 
ATTACHED UPPER LOW JUST INLAND FROM MANZANILLO. ANOTHER UPPER 
RIDGE EXTENDS FROM GUATEMALA TO 13N103W. FARTHER S...A 35 KT 
NORTHEASTERLY JET EXTENDS FROM PANAMA/COSTA RICA SW PAST THE 
GALAPAGOS. THE JET IS PRODUCING UPPER DIFFLUENCE NEAR ITS 
ENTRANCE WITH AN ENHANCEMENT OF DEEP CONVECTION ALONG THE ITCZ. 
A BROAD MONSOON GYRE CONTINUES OFF THE MEXICAN COAST WITH SW/W 
LOW-LEVEL WINDS OVER THE AREA AND NO WELL-DEFINED SURFACE LOW 
CENTER. HOWEVER...MODEL GUIDANCE IS SUGGESTING THAT A WEAK AREA 
OF LOW PRES MAY CONSOLIDATE WITHIN THE NEXT 24-48 HRS OFF THE 
COAST OF ACAPULCO. ASIDE FROM ITCZ CONVECTION...SCATTERED 
MODERATE/STRONG CONVECTION IS NEAR THE GULF OF TEHUANTEPEC FROM 
13N-17N BETWEEN 92W-98W.

W OF 110W...
A FAIRLY STRONG UPPER HIGH IS CENTERED JUST W OF CABO SAN LUCAS 
NEAR 23N113W AND IS PRODUCING MODERATE/STRONG SINKING N OF 15N E 
OF 130W. STRONG NORTHERLY LOW-LEVEL FLOW IS STREAMING DOWN THE 
CALIFORNIA COAST UNDERNEATH THE HIGH AND IS EXPECTED TO 
STRENGTHEN SLIGHTLY OVER THE NEXT 24 HRS...WITH 10-15 FT SWELLS 
MOVING S OF 30N EARLY SAT. FARTHER S...A MID-LEVEL TROUGH 
STRETCHES FROM 15N110W TO 3N125W AND IS ALSO PRODUCING MODERATE 
SUBSIDENCE BETWEEN 110W-130W. A LARGE CYCLONIC UPPER LEVEL 
CIRCULATION LIES W OF 125W WITH AN EMBEDDED TROUGH AXIS FROM 
23N140W TO 29N125W. THE SUBTROPICAL JET LIES S OF THE UPPER LOW 
OVER THE CENTRAL PACIFIC BUT THEN VIRTUALLY VANISHES ONCE IT 
CROSSES 140W...WITH A BAND OF HIGH LEVEL CLOUDS FROM 4N-14N W OF 
130W. THE ITCZ IS QUITE LINEAR AT THE MOMENT BUT ESSENTIALLY 
VOID OF DEEP CONVECTION DUE TO THE LACK OF DEEP TROPICAL 
MOISTURE AND SUBSIDENCE IN THE MID/UPPER LEVELS OF THE 
ATMOSPHERE.

$$
BERG