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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 061524
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC FRI MAR 06 2015

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 
1515 UTC. 

...SPECIAL FEATURE...

A STORM WARNING IS IN EFFECT FOR THE GULF OF TEHUANTEPEC.  
STRONG N-NE 30-45 KT GALE WINDS WITH SEAS OF 9-13 FT AT SUNRISE 
THIS MORNING IS EXPECTED TO STRENGTHEN TO A MINIMAL 40-50 KT 
STORM EVENT THIS EVENING...WITH SEAS BUILDING TO A MAXIMUM OF 
ABOUT 26 KT NEAR 13.5N96W LATE TONIGHT. THE GRADIENT SHOULD 
BEGIN TO RELAX LATE TONIGHT WITH THE NORTHERLY FLOW DIMINISHING 
TO A STRONG GALE AROUND SUNRISE ON SAT...THEN CONTINUE TO WEAKEN 
THROUGHOUT THE DAY SAT INTO SAT NIGHT WITH ONLY MINIMAL GALE 
CONDTIONS EXPECTED AT SUNRISE ON SUN...AND BELOW GALE FORCE 
WINDS BY SUN AFTERNOON. THE NEXT TEHUANTEPEC EVENT IS EXPECTED 
TO BEGIN WITH 20-25 KT NORTHERLY WINDS ON TUE NIGHT...GRADUALLY 
INCREASING TO A MINIMAL GALE ON WED EVENING THROUGH SUNRISE ON 
THU.      

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

A LOW LEVEL TROUGH EXTENDS SW FROM THE PACIFIC COAST OF COLOMBIA 
FROM 06N77W TO 02N81W. SCATTEROMETER WINDS INDICATE THAT THE 
ITCZ FORMS NEAR 04N85W AND CONTINUES W TO AN EMBEDDED LOW LEVEL 
TROUGH AT 05N104W. THE ITCZ CONTINUES SW FROM THE TROUGH TO 
03N115W...THEN TURNS NW TO 07N130W WHERE IT LOSES IDENTITY. 
OVERCAST LOW-MID LEVEL CLOUDS WITH EMBEDDED LIGHT SHOWERS IS 
OBSERVED S OF 06N E OF 84W TO THE COAST OF COLOMBIA IN 
ASSOCIATION WITH THE LOW LEVEL TROUGH. SIMILAR CONDITIONS ARE 
OBSERVED S OF 07N BETWEEN 100-110W ALONG THE ITCZ AND THE 
EMBEDDED TROUGH. SMALL CLUSTERS OF SCATTERED MODERATE CONVECTION 
HAVE BEEN FLARING INTERMITTENTLY ALONG THE ITCZ WITHIN 120 NM OF 
07N126W...AND ALSO WELL N OF THE ITCZ NEAR 11N120W.

SCATTEROMETER WINDS AND BUOYS INDICATE A SECOND ITCZ ALONG A LINE 
FROM 06S90W TO 06S95W TO 03.4S110W TO 03.4S120W TO BEYOND 
04S140W. 

...DISCUSSION... 

ALOFT...AN UPPER SHORT WAVE RIDGE EXTENDS FROM 10N144W TO A  
CREST AT 33N129W. TO THE W OF THIS RIDGE IS A DEEP LAYERED 
TROUGH NOTED W OF THE DISCUSSION AREA ROUGHLY TO THE N OF THE 
HAWAIIAN ISLANDS. TO THE E OF THE RIDGE IS AN UPPER CYCLONE AT 
30N117W WITH AN UPPER TROUGH EXTENDING SE TO A BASE AT 12N114W. 
AN UPPER ANTICYCLONE IS OVER THE DEEP TROPICS NEAR 10N94W. DENSE 
DEBRIS MOISTURE ORIGINATING FROM ITCZ CONVECTION OVER THE 
CENTRAL PACIFIC...AND JUST W OF THE DISCUSSION AREA NEAR 
11N145W...IS ADVECTED E INTO THE DISCUSSION UNDER THE UPPER 
RIDGE. SOME OF THIS MOISTURE MAY ROTATE CYCLONICALLY NE THROUGH 
THE UPPER TROUGH AND ACROSS THE BAJA CALIFORNIA PENINSULA 
TONIGHT. OTHERWISE...THE UPPER LEVELS APPEAR VERY DRY ACROSS THE 
TROPICS E OF 113W AND SUPPRESSING CONVECTION ALONG THE ITCZ. 

A SURFACE RIDGE EXTENDS FROM 32N124W TO 15N105W. THE TRADES SW 
OF THE RIDGE ARE AT 15-20 KT WITH COMBINED SEAS OF 7-9 FT IN 
MIXING NE TRADES...ALONG WITH LONG PERIOD S AND NW SWELL. THE 
GRADIENT IS EXPECTED TO INCREASE SW OF THE RIDGE OVER THE 
WEEKEND...WITH EMBEDDED PATCHES OF 20-25 KT WINDS AND SEAS 
BUILDING TO 10 FT. REINFORCING NE SWELL...ORIGINATING FROM A 
STORM EVENT IN THE GULF OF TEHUANTEPEC...WILL PROPAGATE WSW INTO 
THE TROPICAL WATERS TO THE S OF 13N...AND SPREAD W ACROSS THE 
WATERS BETWEEN 110-120W WELL INTO NEXT WEEK MIXING WITH THE NE 
TRADE WIND SWELL. 

GULF OF CALIFORNIA...NW 20-25 KT WINDS CURRENTLY OBSERVED TO THE 
N OF 28N ARE EXPECTED TO DIMINISH TO 10-15 KT THIS EVENING. 
COMBINED SEAS ESTIMATED TO 6 FT IN THE OPEN LONG FETCH WATERS 
SHOULD SUBSIDE TO 3-4 FT THIS EVENING.     

GULF OF PAPAGAYO AND FONSECA...NE 20-25 KT WINDS IN AND 
DOWNSTREAM OF THE GULF OF PAPAGAYO WILL INCREASE TO 20-30 KT 
DURING THE LATE NIGHT HOURS...AND SPREAD AS FAR SW AS 09N93W. 
THE ENHANCED NE WINDS WILL ALSO SPREAD N ALONG THE COAST OF 
NICARAGUA TO THE GULF OF FONSECA MAINLY DURING THE LATE NIGHT 
HOURS THROUGH SUN NIGHT. THE GRADIENT IS EXPECTED TO RELAX 
CONSIDERABLY ON MON...WITH ONLY A SMALL AREA OF 20-25 KT 
CONDITIONS ON MON NIGHT AND TUE NIGHT.

.GULF PANAMA...NORTHERLY 15-20 KT WINDS AT SUNRISE THIS MORNING 
ARE EXPECTED TO INCREASE TO 20-25 KT THIS EVENING...AND SPREAD 
AS FAR S AS 05N81W TONIGHT...AND AS FAR SW AS 03.5N82.5W ON SAT 
NIGHT WITH MAX SEAS OF 9 FT EACH NIGHT DOWNSTREAM OF THE GULF 
PANAMA. 

$$ 
NELSON