Tropical Weather Discussion
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000
AXPZ20 KNHC 250302
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT APR 25 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0230 UTC.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 09N83W TO 06N96W. THE ITCZ
AXIS EXTENDS FROM 06N96W TO 07N108W THEN RESUMES FROM 06N127W TO
05N140W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS
FROM 02N TO 08N BETWEEN 82W AND 91W...FROM 03N TO 06N BETWEEN
93W AND 98W...AND ALSO WITHIN 120 NM EITHER SIDE OF THE AXIS W
OF 132W.

...DISCUSSION...

A MIDDLE TO UPPER LEVEL TROUGH DOMINATES THE NW AND N CENTRAL
WATERS EXTENDING FROM 32N109W THROUGH 20N115W TO 11N124W. WATER
VAPOR SATELLITE IMAGERY SHOWS MAINLY DRY AND STABLE AIR W OF THE
TROUGH AXIS. A LARGE AND EXPANSIVE UPPER LEVEL ANTICYCLONE IS
ANCHORED OVER THE NW CARIBBEAN SEA WITH ANTICYCLONIC FLOW ALOFT
AROUND IT ACROSS THE NE TROPICAL PACIFIC WATERS TO THE E OF THE
UPPER TROUGH. UPPER LEVEL SW FLOW IS TRANSPORTING DEEP TROPICAL
MOISTURE FROM THE ITCZ TO THE NE ACROSS N CENTRAL MEXICO AHEAD
OF THE UPPER TROUGH AND AROUND THE UPPER ANTICYCLONE.

AT THE SURFACE...A HIGH CENTER IS LOCATED NEAR 32N142W WITH A
RIDGE AXIS EXTENDING TO THE SE THROUGH 28N127W TO 16N107W. A
PAIR OF TROUGHS ARE EMBEDDED IN THE ITCZ ACROSS THE CENTRAL
WATERS. THE PRESSURE GRADIENT ACROSS THE W CENTRAL WATERS IS
TIGHT ENOUGH BETWEEN THESE FEATURES TO SUPPORT FRESH TO STRONG
NE-E TRADE WINDS WITH AN AREA OF SURROUNDING COMBINED SEAS OF 8-
11 FT. THESE CONDITIONS WILL PERSIST ACROSS THE SAME GENERAL
AREA THROUGH THE NEXT 48 HOURS OR SO.

FRESH TO STRONG NORTHERLY WINDS ARE OCCURRING JUST N OF THE
AREA AROUND AND OFFSHORE OF POINT CONCEPTION CALIFORNIA. THESE
WINDS ARE HELPING TO MAINTAIN NORTHERLY SWELL WHICH IS SEEPING
INTO THE N CENTRAL DISCUSSION WATERS. THIS SWELL WILL DECAY TO
LESS THAN 8 FT BY SAT MORNING. A NEW ROUND OF FRESH TO STRONG NW-
N WINDS WILL DEVELOP OFFSHORE OF SOUTHERN CALIFORNIA AND ALSO
OFFSHORE OF BAJA CALIFORNIA NORTE SUN WITH ASSOCIATED SEAS
BUILDING BACK TO 8-10 FT BY SUN EVENING.

GULF OF CALIFORNIA...TROUGHING EXTENDS FROM FAR NW MEXICO INTO
THE FAR NORTHERN GULF. SOUTHERLY FLOW IN THE GULF OF CALIFORNIA
HAS DIMINISHED SLIGHTLY TO 15-20 KT WHICH WILL PERSIST THROUGH
EARLY SAT. THE PRESSURE GRADIENT ACROSS THE REGION WILL THEN
TIGHTEN SAT AFTERNOON WITH A POCKET OF 20-30 KT SOUTHWESTERLY
WINDS FROM 29.5N TO 30.5N BY 00 UTC SUN INTO SAT EVENING.

GULF OF PAPAGAYO...GAP WINDS ARE FORECAST TO PULSE TO FRESH
LEVELS AGAIN LATE TONIGHT INTO EARLY SAT DURING PEAK NOCTURNAL
DRAINAGE FLOW.

GULF OF PANAMA...NORTHERLY WINDS WILL BRIEFLY INCREASE TO FRESH
LEVELS JUST SW OF THE IMMEDIATE GULF LATE TONIGHT THROUGH THE
MORNING SAT AS THE LOCAL PRESSURE GRADIENT BRIEFLY TIGHTENS.

$$
LEWITSKY



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