000
AXPZ20 KNHC 072145
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC FRI JUN 07 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS NW FROM THE COAST OF COLOMBIA AT
FROM 06N77W TO ACROSS W PANAMA THEN ALONG THE PACIFIC COAST 
OF COSTA RICA TO OVER THE PACIFIC AT 10N86W THEN W TO 
11.5N96W TO AN EMBEDDED 1009 MB LOW PRESSURE AT 11N104W... WITH 
THE MONSOON TROUGH CONTINUING W TO A SECOND LOW PRESSURE 1010 MB 
NEAR 10N120W...WITH THE MONSOON TROUGH EXTENDING SW OF THE LOW 
TO 09N123W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN 
ITCZ. THE ITCZ AXIS CONTINUES W TO BEYOND 08N140W. ISOLATED 
MODERATE TO STRONG CONVECTION IS NOTED FROM 05N TO THE COAST OF 
CENTRAL AMERICA TO THE E OF 97W...AND ALSO WITHIN 90 NM S OF THE 
ITCZ AXIS BETWEEN 138W AND 140W.

SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN
210 NM OVER THE S SEMICIRCLE OF THE LOW PRESSURE AT 11N104W...
AND ALSO WITHIN 150 NM OVER THE NW QUADRANT OF THE LOW. THIS 
LOW IS EXPECTED TO REMAIN WITHIN THE MONSOON TROUGH NEAR 
11.5N105W EARLY SAT...AND NEAR 13N107W EARLY SUN AS THE TROUGH
SHIFTS NORTHWARD. 
 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED OVER
THE W SEMICIRCLE OF THE LOW PRESSURE AT 10N120W...ROUGHLY WITHIN
120 NM EITHER SIDE OF A LINE FROM 08N124W TO 11N119W. GUIDANCE 
SUGGEST THIS LOW WILL LOSE IDENTITY ALONG THE MONSOON TROUGH AXIS 
IN A FEW HOURS. 

...DISCUSSION...                                                
A MID TO UPPER LEVEL TROUGH EXTENDS SW FROM AN UPPER CYCLONE
OVER SOUTHERN CALIFORNIA NEAR 33N121W THROUGH 31N134W TO 
ANOTHER UPPER CYCLONE CUTTING OFF N OF THE HAWAIIAN ISLANDS
AT 23N154W. AN UPPER CYCLONE CONTINUES OVER THE DEEP TROPICS 
AT 02N128W WITH AN UPPER RIDGE EXTENDING INTO THE AREA ALONG
04N140W TO 05N136W. THESE FEATURES COMBINE TO PRODUCE A SMALL
AREA OF UPPER DIFFLUENCE WHICH IS ENHANCING THE CONVECTION
ALONG THE ITCZ BETWEEN 137W-157W. AN UPPER ANTICYCLONE IS 
QUASI STATIONARY AT 23N117W...WITH AN UPPER RIDGE EXTENDING
E TO A SHARP CREST OVER COASTAL OLD MEXICO AT 18N101W. AN UPPER
RIDGE ALSO EXTENDS W TO A CREST AT 14N139W. WEAK UPPER DIFFLUENCE
ALONG THE SOUTHERN PERIPHERY OF THIS UPPER RIDGE IS IN PHASE WITH
THE MONSOON TROUGH AXIS AS IS LIKELY SUPPORTING THE CONVECTION
PREVIOUSLY DESCRIBED NEAR THE TWO EMBEDDED SURFACE LOWS.

AN UPPER TROUGH EXTENDS S ACROSS THE GULF OF MEXICO WITH
THE BASE OF TROUGH CONTINUING OVER THE ISTHMUS OF TEHUANTEPEC.
A BROAD UPPER RIDGE IS NOTED ACROSS THE TROPICAL PORTION OF THE
DISCUSSION AREA TO THE E OF 100W. A MOISTURE PLUME IS OBSERVED
UNDER THE RIDGE AND AHEAD OF THE UPPER TROUGH OVER CENTRAL 
AMERICA BETWEEN 93W-86W...AND EXTENDS NNE ACROSS THE NW 
CARIBBEAN FEEDING INTO THE CONVECTION OVER THE SE GULF OF
MEXICO APPROACHING THE SW COAST OF FLORIDA. 

$$
NELSON