000
AXPZ20 KNHC 031539
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                        
1605 UTC FRI MAY 03 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1400 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...             
THE MONSOON TROUGH AXIS WAS ANALYZED FROM 09N78W TO 09N100W TO 
08N109W TO 08N116W. THE ITCZ AXIS WAS ANALYZED FROM 08N116W TO 
04N140W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS  
WITHIN 150 NM EITHER SIDE OF THE AXIS BETWEEN 98W AND 128W. 
SCATTERED MODERATE CONVECTION WAS WITHIN 390 NM N OF THE AXIS 
BETWEEN 128W AND 136W AS WELL AS WITHIN 210 NM S AND 90 NM N OF 
THE AXIS BETWEEN 80W AND 85W. 

...DISCUSSION...                                             
GULF OF TEHUANTEPEC...WINDS IN THE GULF OF TEHUANTEPEC ARE 
PICKING UP THIS MORNING. SMOKE FROM INLAND FIRES IS BEING PUSHED 
SOUTHWARD INTO THE GULF ACCORDING TO THE LATEST VISIBLE 
SATELLITE IMAGERY. THERE HAVE BEEN NO WIND OBSERVATIONS IN THE 
GULF THIS MORNING...BUT WINDS AT SALINA CRUZ HAVE GONE FROM N-NE 
AT 15 KT AT 1200 UTC TO DUE N AT 30 KT BY 1500 UTC. THE LATEST 
FORECAST GUIDANCE SHOWS 25-30 KT WINDS IN THE GULF BY 1200 UTC. 
WINDS ARE EXPECTED TO PICK UP TO GALE FORCE THIS AFTERNOON AS 
THE COLD FRONT IN THE GULF OF MEXICO MAKES ITS WAY THROUGH 
CHIVELA PASS AND HIGH PRESSURE BUILDS BEHIND IT IN NE MEXICO. 
GALE CONDITIONS ARE FORECAST TO DIMINISH BY SUNRISE SAT WHEN THE 
HIGH PRESSURE RAPIDLY WEAKENS AS A NEW FRONT MOVES INTO THE 
NORTHERN GULF OF MEXICO. BY SUN MORNING...WIND AND SEAS WILL 
DROP BELOW ADVISORY CONDITONS...WITH WINDS 20 KT OR LESS AND 
SEAS LESS THAN 8 FT NEAR THE GULF OF TEHUANTEPEC.

ELSEWHERE...A FLAT AND WEAK SUBTROPICAL SURFACE RIDGE OVER THE 
FORECAST AREA WILL WEAKEN FURTHER AS LOW PRESSURE DEVELOPS ALONG 
THE CALIFORNIA COAST AND EATS INTO THE EASTERN EDGE OF THE 
RIDGE. WINDS AND SEAS OVER THE REMAINDER OF THE FORECAST AREA 
WILL REMAIN BELOW ADVISORY CONDITIONS THROUGH AT LEAST SUN 
MORNING.

SOUTHWESTERLY FLOW ON THE SE SIDE OF A STRONG UPPER LOW NEAR 
27N137W IS DIRECTING MID-TO UPPER-LEVEL TROPICAL MOISTURE TOWARD 
BAJA CALIFORNIA. ISOLATED TO SCATTERED CIRRUS CAN BE FOUND N OF 
22N E OF 135W INTO THE GULF OF CALIFORNIA AS A RESULT.

AN UPPER RIDGE AXIS STRETCHES FROM COLOMBIA THROUGH NORTHERN 
PANAMA TO 10N111W WHERE IT IS DISRUPTED BY A TROUGH AXIS BEFORE 
CONTINUING ON FROM 10N117W TO 04N130W. PRIMARILY DIVERGENT FLOW 
ALONG THE RIDGE AXIS IS ENHANCING THE SCATTERED MODERATE WITH 
ISOLATED STRONG CONVECTION NEAR THE MONSOON TROUGH/ITCZ AXIS 
DESCRIBED IN THE SECTION ABOVE W OF 98W. DIFFLUENT FLOW ALOFT 
NEAR THE GULF OF FONSECA BETWEEN 5 KT SOUTHWESTERLY WINDS JUST N 
OF THE AFOREMENTIONED RIDGE AXIS AND 40-60 KT ALONG 17N ON THE 
SOUTHERN SIDE OF A ZONAL UPPER JET IS ENHANCING 
CONVECTION...WITH SCATTERED MODERATE CONVECTION FOUND WITHIN 60 
NM OF COAST BETWEEN 86W AND 90W. THESE CONDITIONS ARE EXPECTED 
TO CHANGE LITTLE OVER THE NEXT DAY OR SO.

$$
SCHAUER