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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 210231
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON APR 21 2014

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0215 UTC. 

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

AN ILL-DEFINED MONSOON TROUGH EXTENDS W FROM THE COAST OF 
COLOMBIA AT 04N77W TO 04.5N80W THEN TURNS NW TO 06N91W WHERE 
SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ AXIS. THE 
ITCZ AXIS CONTINUES W TO 06N107W THEN WSW TO 04.5N120W...THEN 
WNW TO BEYOND 07N140W.

SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED OVER AND  
TO THE S OF OF THE MONSOON TROUGH AND ITCZ WITHIN 180 NM EITHER 
SIDE OF A LINE FROM 03N86W TO 07N100W...AND ALONG THE WESTERN 
SEGMENT OF THE MONSOON TROUGH WITHIN 90 NM EITHER SIDE OF A LINE 
FROM 11N118W TO 06N133W TO 06N140W. SCATTERED MODERATE CONVECTION 
IS OBSERVED ALONG THE ITCZ WITHIN 120 NM OF 04N117W.  

...DISCUSSION...                                       

AN UPPER CYCLONE IS OVER THE OKLAHOMA PANHANDLE WITH A MID TO 
UPPER TROUGH EXTENDING SW ACROSS NORTHERN OLD MEXICO AND THE 
BAJA CALIFORNIA PENINSULA TO A BASE OVER THE TROPICAL EPAC NEAR 
10N126W. A 180 NM WIDE BAND OF UPPER DEBRIS MOISTURE CONTINUES E 
OF THIS TROUGH AXIS. THE MOISTURE ORIGINATES IN THE DEEP TROPICS 
NEAR 10N116W...AND SPREADS NE ACROSS THE PACIFIC COAST OF MEXICO 
AT 19N106W...THEN ACROSS THE CENTRAL GULF OF MEXICO. ANOTHER MID-
UPPER SHORTWAVE TROUGH IS APPROACHING THE FAR NW PORTION OF THE 
DISCUSSION AREA...AND IS PRECEDED BY A LARGE AREA OF UPPER 
MOISTURE OBSERVED TO THE N OF 28N AND W OF 126W...WITH THE 
EASTERN EDGE OF THIS MOISTURE THINNING AS IT SPREADS E ACROSS 
THE CALIFORNIA COAST NEAR 34N. OTHERWISE...DRY UPPER AIR IS 
NOTED ACROSS THE DISCUSSION AREA BETWEEN THESE UPPER TROUGHS... 
ROUGHLY WITHIN 540 NM EITHER SIDE OF A LINE FROM 30N108W TO 
18N131W.

AN UPPER ANTICYCLONE IS NOTED JUST W OF THE AREA AT 07N146W WITH 
A RIDGE EXTENDING E INTO THE DISCUSSION AND OVER THE WESTERN 
SEGMENT OF THE MONSOON TROUGH...AND ENHANCING THE PREVIOUSLY 
DESCRIBED CONVECTION ALONG THE ITCZ TO THE W OF 125W. AN ILL-
DEFINED LOW-MID LEVEL TROUGH IS NOTED FROM 19N109W TO 10N125W 
WITH CONVECTION FLARING SE OF THE TROUGH AS PREVIOUSLY 
MENTIONED. THE DEBRIS MOISTURE FROM THIS CONVECTION CONCENTRATES 
INTO THE TROPICAL PLUME ALSO ALREADY MENTIONED. JUST TO E IS 
ANOTHER UPPER ANTICYCLONE IS CENTERED AT 07N105W WITH AN UPPER 
RIDGE EXTENDING NE TO A CREST AT 14N96W. UPPER DIFFLUENCE 
ENHANCED SCATTERED MODERATE ISOLATED STRONG CONVECTION EARLIER 
ALONG THE TROUGH...BUT THE CONVECTION IS CURRENTLY ONLY ISOLATED 
AT BEST. 

A WEAK UPPER TROUGH EXTENDS SW FROM OVER HONDURAS TO A BASE OVER 
THE DEEP TROPICS AT 07N96W. THIS TROUGH EFFECTIVELY SEPARATES 
THE UPPER ANTICYCLONIC FLOW JUST DESCRIBED FROM THE FLOW 
ASSOCIATED WITH ANOTHER E TO W UPPER RIDGE EXTENDING W OFF THE 
COAST OF COLOMBIA ALONG 05N TO A CREST NEAR 05N92W. WEAK 
DIFFLUENCE ALONG THIS EASTERN RIDGE IS SUPPORTING THE PREVIOUSLY 
DESCRIBED CONVECTION ALONG THE MONSOON TROUGH AND ITCZ BETWEEN 
85-98W. DEBRIS MOISTURE FROM CONVECTION OVER PANAMA AND COSTA 
RICA IS STREAMING NE ACROSS THE SW AND CENTRAL CARIBBEAN.

A SURFACE RIDGE EXTENDS FROM 34N132W TO NEAR 14N102W. NE TRADES 
ARE ENHANCED TO 15-20 KT BETWEEN THE RIDGE AND 06N TO THE W OF 
115W...WITH SEAS OF 7-10 FT IN MIXED LONG PERIOD NW AND LONG 
PERIOD CROSS-EQUATORIAL S SWELL. THIS AREA OF ENHANCED SEAS WILL 
BE REINFORCED ON MON BY A NEW BATCH OF NW SWELL THAT HAS MOVED 
INTO THE DISCUSSION WATERS NW OF A LINE FROM 32N120W TO 21N140W. 
THE NW SWELL WILL CONTINUE TO PROPAGATE E REACHING THE NW COAST 
OF THE BAJA PENINSULA IN THE FORM OF COMBINED SEAS OF 6-9 FT ON 
MON...THEN GRADUALLY SUBSIDING ACROSS THE DISCUSSION WATERS N OF 
20N THROUGH TUE. THE PRESSURE GRADIENT WILL TIGHTEN ON TUE NIGHT 
WITH NW WINDS INCREASING TO 15-25 KT ACROSS THE WATERS N OF 25N 
E OF 122W TO BAJA PENINSULA ON WED. THESE WINDS WILL DIMINISH 
AND THE SEAS WILL SUBSIDE ON THU.  

$$
NELSON