000
AXPZ20 KNHC 081006
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN JUN 08 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 
0915 UTC.

...TROPICAL WAVES...
TROPICAL WAVE THROUGH HONDURAS IS ALONG 86W S OF 17N MOVING W 
10 KT. WAVE IS MOSTLY INLAND OVER CENTRAL AMERICA AND REMAINS 
EMBEDDED WITHIN AN AREA OF DEEP LAYERED MOISTURE MASKING ANY 
SATELLITE SIGNATURE. THE POSITION IS BASED LARGELY ON CONTINUITY.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 07N87W TO 08N85W TO 13N98W TO 
06N140W. SCATTERED MODERATE CONVECTION WITHIN 60 NM OF AXIS E OF 
90W. SCATTERED MODERATE CONVECTION WITHIN 30 NM N OF AXIS 
BETWEEN 120W AND 125W.

...DISCUSSION...

E OF 110W...
MAIN ITEM OF INTEREST IS A DEVELOPING LOW PRESSURE AREA JUST 
WEST OF THE GULF OF TEHUANTEPEC NEAR 14N97W. THIS FEATURE 
DEMONSTRATES PERSISTENT CYCLONIC CURVATURE ON IR SATELLITE 
IMAGERY AND IS IN AN AREA OF GOOD DIVERGENCE ALOFT ON THE 
SOUTHERN PORTION OF AN UPPER ANTICYCLONE. THE CIRCULATION 
OBSERVED ON SATELLITE IMAGERY MAY BE AT THE MID LEVELS 
HOWEVER...SINCE SHIP OBSERVATIONS FROM 00Z AND 06Z SHOW 
SOUTHERLY FLOW TO THE WEST OF THE CIRCULATION. VISIBLE SATELLITE 
IMAGERY AND SCATTEROMETER PASSES MAY SHED LIGHT ON THIS. AT ANY 
RATE...THE SYSTEM REMAINS WEAK IN AN AREA OF MODERATE SHEAR. THE 
LOW IS INTERACTING WITH THE MEXICAN COAST...WHERE EVENING 
CONVECTION IS FLARING JUST OFFSHORE AROUND THE LOW CENTER. 
GLOBAL MODEL CONSENSUS SHOW A WEAK LOW FORMING TO THE WEST OF 
THIS POSITION SOUTH OF ACAPULCO THROUGH SUNDAY...BUT WITH A 
GENERAL NW DRIFT ALONG OR TOWARD LAND...LIKELY WEAKENING THE 
SYSTEM. THE APPROACHING WEAK TROPICAL WAVE FROM THE EAST MAY 
INTERACT WITH THE DEVELOPING LOW...ADDING TO CONVECTIVE 
POTENTIAL ALONG THE MEXICAN COAST AND JUST INLAND. THIS WILL BE 
LIMITED TO SOUTH OF 20N. MODELS INDICATE THE UPPER RIDGE WILL 
SHIFT NW AS AN UPPER TROUGH DIGS THROUGH THE ROCKIES. THIS WILL 
BRING DRIER AIR SOUTH INTO CENTRAL MEXICO THROUGH EARLY NEXT 
WEEK...LIMITING MUCH CONVECTIVE DEVELOPMENT TO THE NORTH. 
MEANWHILE...LONG PERIOD SW SWELL OF UP TO 7 FT WILL PUSH INTO 
SOUTHERN MEXICO AND CENTRAL AMERICA BY TUE THEN DECAY.

W OF 110W...
A TIGHT PRESSURE GRADIENT REMAINS IN PLACE BETWEEN A 1000 MB 
PRESSURE OVER SOUTHERN NEVADA AND A 1032 MB NEAR 38N136W. SHIPS  
OFF THE CALIFORNIA COAST WERE REPORTING 30 KT NLY FLOW...AND 20 
TO 25 KT GENERALLY S OF 30N...CORROBORATING ASCAT AND QUIKSCAT 
PASSES. SEAS HEIGHTS ARE PUSHING 12 TO 14 FT IN N SWELL. FURTHER 
SOUTH...LONG PERIOD SW CROSS-EQUATORIAL FLOW UP TO 8 FT IS 
EXPECTED S OF 10N. MEANWHILE AN UPPER LOW IS CENTERED NEAR 
22N135W...WEST OF AN UPPER ANTICYCLONE OVER MEXICO. THE 
RESULTANT SOUTHERLY FLOW ALOFT BETWEEN THE TWO SYSTEMS IS AIDING 
CONVECTION ALONG THE ITCZ AS NOTED ABOVE BETWEEN 120W AND 125W. 
OTHERWISE...DEEP LAYER MOISTURE REMAINS LIMITED AND CONVECTION 
SPARSE.

$$
CHRISTENSEN