000
AXPZ20 KNHC 051545
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT JUL 05 2008

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 
1515 UTC.

...SPECIAL FEATURE...

A 1007 MB LOW IS LOCATED NEAR 13N99W...OR ABOUT 230 NM SSE OF 
ACAPULCO MEXICO...MOVING WNW 5-10 KT. DEEP CONVECTION HAS 
INCREASED SUBSTANTIALLY OVER THE PAST 12 HRS OR SO MAINLY OVER 
THE WESTERN SEMICIRCLE WITH THE COLDEST CLOUD TOP TEMPERATURES 
AROUND -85C. NUMEROUS MODERATE/STRONG CONVECTION IS FROM 10N-16N 
BETWEEN 96W-104W. THE SYSTEM IS SLOWLY BECOMING MORE ORGANIZED 
DESPITE BEING IMPACTED BY 20-25 KT OF NE/EASTERLY SHEAR ON THE S 
SIDE OF AN UPPER HIGH OVER SW MEXICO. IN FACT...NEW BANDING IS 
STARTING TO FORM ON THE SE SIDE OF THE CENTER...MAKING THE 
SYSTEM A LITTLE BIT LESS ASYMMETRIC. THERE IS A ZONE OF LIGHTER 
SHEAR NEAR THE MEXICAN COAST...AND THE SYSTEM ONCE AGAIN HAS THE 
POSSIBILITY OF BECOMING A TROPICAL CYCLONE OVER THE NEXT 48 HRS 
AS IT MOVES SLOWLY NW JUST OFFSHORE SOUTHERN MEXICO.

...TROPICAL WAVES...

TROPICAL WAVE EXTENDS FROM GUATEMALA SWD TO 05N ALONG 90W MOVING 
W 10-15 KT. THE WAVE IS RATHER DISORGANIZED AND IS BEGINNING TO 
MOVE INTO THE CIRCULATION ASSOCIATED WITH THE LOW SSE OF 
ACAPULCO. SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 
09N-13N BETWEEN 88W-92W.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 06N77W TO 11N92W TO 12N110W TO 
12N124W TO 06N140W. SCATTERED MODERATE/STRONG CONVECTION FROM 
05N-12N BETWEEN 79W-91W. SCATTERED MODERATE/ISOLATED STRONG S OF 
AXIS TO 06N BETWEEN 94W-111W. ISOLATED MODERATE WITHIN 60 NM OF 
AXIS BETWEEN 116W-132W.

...DISCUSSION...

SUBTROPICS...
THERE IS NO SIGNIFICANT WEATHER ACROSS THE SUBTROPICAL PACIFIC 
AT THE MOMENT. A DECAYING UPPER LEVEL TROUGH AXIS EXTENDS FROM 
30N120W TO 28N132W TO 24N140W AND IS MOVING W AS AN UPPER HIGH 
BUILDS NEAR 27N125W. A WEAK UPPER LOW IS LOCATED ADJACENT TO 
BAJA CALIFORNIA NEAR 26N114W WITH A TROUGH EXTENDING TO 23N122W. 
DEEP MOISTURE IS QUITE LIMITED...EXCEPT E OF 120W IN THE 
VICINITY OF THE REMNANT LOW OF DOUGLAS...AND THE UPPER LEVEL 
FEATURES ARE PRODUCING MODERATE/STRONG SUBSIDENCE FROM BAJA 
CALIFORNIA WWD TO 140W. THE REMNANT LOW OF DOUGLAS IS CENTERED 
NEAR 20N114W...OR ABOUT 260 NM SW OF CABO SAN LUCAS MEXICO...AND 
IS MOVING W AT 5 KT WITH A PRESSURE OF 1007 MB. THE CIRCULATION 
HAS REMAINED INTACT WITH A SWIRL OF BROKEN/OVERCAST STRATUS AND 
EMBEDDED ISOLATED SHOWERS WITHIN 360 NM NW AND 150 NM SE 
SEMICIRCLES. THERE IS SOME DEEPER MOISTURE OVER MEXICO EXCEPT 
WHERE AN UPPER TROUGH OVER THE RIO GRANDE VALLEY IS DRAGGING 
DRIER AIR SWD OVER THE MEXICAN PLATEAU N OF 26N E OF 108W. 
OTHERWISE SPOTTY SHOWERS/TSTMS ARE LINGERING OVER THE SPINE OF 
THE SIERRA MADRE OCCIDENTALS.

TROPICS...
THE REMNANT LOW OF BORIS IS CENTERED NEAR 16N135W...OR ABOUT 
1100 NM ESE OF THE BIG ISLAND OF HAWAII...AND IS MOVING WSW AT 
10 KT WITH A PRESSURE OF 1008 MB. THE CIRCULATION CONSISTS 
MAINLY OF BROKEN STRATUS WITHIN 480 NM OF THE CENTER WITH 
EMBEDDED ISOLATED SHOWERS WITHIN 240 NM N QUADRANT. THE LOW IS 
EXPECTED TO MOVE W OF 140W BY LATE SUN NIGHT. IN THE UPPER 
LEVELS...AN UPPER HIGH IS CENTERED NEAR 09N141W WITH AN ADJACENT 
INVERTED TROUGH FROM 05N120W TO 17N130W. A 30-35 KT UPPER LEVEL 
EASTERLY JET LIES ROUGHLY ALONG 16N BETWEEN THIS TROUGH AND AN 
UPPER HIGH OVER MEXICO...AND HAPPENS TO BE PROVIDING UPPER 
DIFFLUENCE NEAR THE LOW SSE OF ACAPULCO. OTHERWISE...THE REST OF 
THE AREA E OF 110W IS UNDER NE/EASTERLY FLOW ALOFT WITH COPIOUS 
DEEP-LAYERED MOISTURE IN PLACE.

$$
BERG