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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

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