000
AXPZ20 KNHC 230907
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1005 UTC TUE APR 23 2013

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0730 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
THE MONSOON TROUGH AXIS WAS ANALYZED FROM 07N77W TO 06N100W TO 
08N111W TO 08N118W. THE ITCZ AXIS WAS ANALYZED FROM 08N118W TO 
06N140W. SCATTERED MODERATE TO STRONG CONVECTION WAS WITHIN 240 
NM N OF THE AXIS BETWEEN 110W AND 117W AND WITHIN 330 NM S OF 
THE AXIS TO 03N BETWEEN 104W AND 113W. SCATTERED MODERATE 
CONVECTION WAS WITHIN 210 NM S OF THE AXIS BETWEEN 91W AND 
95W...WITHIN 75 NM N AND 120 NM S OF THE AXIS BETWEEN 100W AND 
103W...AND WITHIN 75 NM N AND 180 NM S OF THE AXIS BETWEEN 134W 
AND 139W. 

...DISCUSSION...                                                 
AN UPPER RIDGE AXIS EXTENDS FROM COLOMBIA ALONG 08N AND IS 
DISRUPTED BY AN UPPER TROUGH NEAR 110W BEFORE CONTINUING FROM 
07N114W TO 03N140W. THIS RIDGE AXIS LIES IN CLOSE PROXIMITY TO 
THE MONSOON TROUGH/ITCZ AXIS. CONVECTION ALONG THE MONSOON 
TROUGH/ITCZ AXIS IS BEING ENHANCED AS LOW-LEVEL MOISTURE POOLED 
ALONG THAT AXIS IS LIFTED BY THE DIFFLUENCE ASSOCIATED WITH THE 
UPPER RIDGE. PRECIPITABLE WATER IMAGERY SHOWS VALUES IN THE 2.0-
2.5 INCH RANGE ALONG THE LENGTH OF THE MONSOON TROUGH/ITCZ. 
UPPER DIFFLUENCE IS MOST VIGOROUS TO THE W OF THE TROUGH WHERE 
SCATTERED MODERATE TO STRONG CONVECTION IS NOTED IN THE SECTION 
ABOVE. THE AFOREMENTIONED TROUGH AXIS SNAKES BETWEEN AN UPPER 
LOW NEAR 01S106W TO ANOTHER UPPER LOW NEAR 31N131W. THE NORTHERN 
LOW IS EXPECTED TO SHIFT 5-10 DEGREES FARTHER E-NE TOWARD 
SOUTHERN CALIFORNIA OVER THE NEXT 48 HOURS. THE SURFACE 
REFLECTION OF THIS LOW AND RESULTANT TROUGHING WILL WEAKEN THE 
SUBTROPICAL RIDGE OVER NE WATERS...KEEPING WINDS THERE LIGHT.

1038 MB HIGH PRES LIES WELL N OF THE AREA NEAR 49N134W AND 
EXTENDS A RIDGE AXIS THROUGH 29N140W TO 20N112W. GENTLE TO 
MODERATE NE TRADE WINDS LIE BETWEEN THE RIDGE AXIS AND THE ITCZ 
OVER WESTERN WATERS. WINDS ARE EXPECTED TO REMAIN BELOW 25 KT 
OVER THE ENTIRE FORECAST AREA THROUGH AT LEAST EARLY THU 
MORNING...BUT N WINDS WELL OFF THE CALIFORNIA COAST N OF THE 
AREA SHOULD BECOME STRONG ENOUGH TO PROPAGATE N SWELL WITH 8-9 
FT SEAS INTO WATERS N OF 28N BETWEEN 129W-139W LATE TUE NIGHT 
THROUGH EARLY THU MORNING. 

FIRES INLAND FROM SOUTHERN MEXICO INTO NW NICARAGUA ARE SENDING 
PATCHY SMOKE INTO OFFSHORE WATERS. THESE CONDITIONS WILL LIKELY 
CONTINUE OVER THE NEXT FEW DAYS.

$$
SCHAUER