000
AXPZ20 KNHC 070920
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON APR 07 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 
0845 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N78W 3N88W THEN CONTINUES ALONG 
10N97W 3N124W 5N140W. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION FROM 5N-7N E OF 79W ALONG THE COLOMBIAN COAST. 
SCATTERED SHOWERS/TSTMS FROM 6N-10N BETWEEN 83W-86W. SCATTERED 
MODERATE WITHIN 60 NM OF AXIS BETWEEN 112W-118W. NUMEROUS 
MODERATE/STRONG FROM 3N-7N W OF 136W.

...DISCUSSION...

W OF 110W...
A NEARLY STATIONARY CUT-OFF MID/UPPER LEVEL LOW IS CENTERED NE 
OF THE HAWAIIAN ISLANDS...BUT W OF THE DISCUSSION AREA...NEAR 
25N146W WITH A BROAD PLUME OF TROPICAL MOISTURE EXTENDING FROM 
THE CENTRAL PACIFIC TROPICS NE TOWARDS THE BAJA PENINSULA. THE 
SUBTROPICAL JET CURVES AROUND THE UNDERSIDE OF THE LOW FROM 
23N140W TO JUST OFF THE CALIFORNIA COAST WHERE IT MERGES WITH 
THE POLAR JET. WIDESPREAD HIGH CLOUDINESS EXTENDS DOWNSTREAM OF 
THE UPPER LOW COVERING MUCH OF THE AREA N OF 12N W OF 120W. 
FARTHER S...A WELL-DEFINED SURFACE TROUGH HAS MOVED W OF THE 
AREA ALONG 143W S OF 9N AND IS UNDER THE INFLUENCE OF STRONG 
WESTERLY SHEAR. A SHARP UPPER TROUGH LIES NEAR THE AREA FROM 
13N140W TO THE EQUATOR AT 130W AND IS PRODUCING STRONG UPPER 
DIFFLUENCE AND A SUBSEQUENT ENHANCEMENT OF DEEP CONVECTION E OF 
THE SURFACE TROUGH AXIS AND ALONG THE ITCZ. ELSEWHERE...AN UPPER 
RIDGE AXIS ALONG 15N E OF 125W IS PRODUCING WIDESPREAD 
SUBSIDENCE S OF 20N E OF 125W.

E OF 110W...
A STRONG MID/UPPER LEVEL RIDGE AXIS LIES ALONG 15N AND IS 
BOUNDED BY STRONG WESTERLY FLOW WHICH EXTENDS ACROSS BAJA 
CALIFORNIA AND MUCH OF MAINLAND MEXICO. A SHORTWAVE TROUGH IS 
EMBEDDED WITHIN THE WESTERLY FLOW ENTERING THE GULF OF 
MEXICO...AND STRONG UPPER CONFLUENCE IS PRODUCING WIDESPREAD 
SUBSIDENCE OVER MEXICO AND THE BULK OF THE PACIFIC WATERS E OF 
110W. AN UPPER LEVEL CYCLONIC SHEAR AXIS EXTENDS FROM 5N110W TO 
8N100W TO 9N90W SEPARATING EASTERLY FLOW TO THE N WITH WESTERLY 
FLOW NEAR THE EQUATOR. THE ITCZ IS POORLY-DEFINED E OF 98W AND 
MUCH OF THAT AREA IS DOMINATED BY LIGHT NORTHERLY LOW-LEVEL FLOW 
WHICH CROSSES THE EQUATOR IN THE VICINITY OF THE GALAPAGOS 
ISLANDS.
  
$$
BERG