Tropical Weather Discussion
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000
AXPZ20 KNHC 010927
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN MAY 01 2016

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0900 UTC.

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

A SURFACE TROUGH EXTENDS FROM 10N98W TO 08N110W TO 06N122W. THE
ITCZ AXIS STRETCHES FROM 05N126N TO BEYOND 03N140W. A SURFACE
TROUGH IS EMBEDDED WITHIN THE ITCZ/TROUGH AND EXTENDS ALONG 123W
FROM 04N TO 10N. SCATTERED MODERATE ISOLATED STRONG CONVECTION
IS NOTED FROM 04N TO 08N BETWEEN 83W AND 87W...FROM 07N TO 10N
BETWEEN 100W AND 105W...AND FROM 04N TO 10N BETWEEN 109W AND
117W.

...DISCUSSION...

HIGH PRES OF 1026 MB LOCATED NEAR 32N140W EXTENDS A RIDGE ACROSS
THE FORECAST WATERS COVERING MAINLY THE AREA N OF 15N W OF 110W.
THE TIGHT PRESSURE GRADIENT BETWEEN THE RIDGE AND LOW PRES OVER
THE SW U.S. IS CAUSING STRONG TO GALE FORCE NW WINDS JUST W OF
THE COAST OF CALIFORNIA. SEAS GENERATED BY THESE WINDS CONTINUE
TO IMPACT THE NE WATERS MAINLY N OF 26N E OF 125W TO THE COAST
OF BAJA CALIFORNIA. A RECENT ALTIMETER PASS SHOWED SEAS OF 10-11
FT NEAR 30N120W. THE PRESSURE GRADIENT WILL BEGIN TO RELAX LATER
TODAY AS THE HIGH PRES DISSIPATES AND A COLD FRONT APPROACHES
FROM THE WEST. THIS WILL ALLOW SEAS TO EVENTUALLY SUBSIDE TO 8
FT OR LESS WEST OF THE CALIFORNIA AND THE BAJA COAST BY MIDDAY
ON MONDAY.

THE PRES GRADIENT BETWEEN THE RIDGE AND LOWER PRES IN THE
VICINITY OF THE ITCZ IS RESULTING IN MODERATE TO FRESH NE-E
TRADES OVER THE WESTERN PORTION OF THE FORECAST REGION FROM 09N
TO 22N W OF 130W WITH SEAS OF 8-9 FT IN MIXED SWELL. ANOTHER
AREA OF 8-9 FT SEAS PRIMARILY IN SW SWELL IS SEEN FROM 13N TO
20N BETWEEN 108W AND 120W. SEAS ARE FORECAST TO SUBSIDE TO LESS
THAN 8 FT ACROSS THE ENTIRE BASIN BY EARLY MON MORNING.

A SURFACE TROUGH EXTENDS SOUTHWARD FROM A LOW PRESSURE OVER
WESTERN ARIZONA INTO THE NORTHERN GULF OF CALIFORNIA. THE TIGHT
GRADIENT BETWEEN HIGH PRESSURE OFFSHORE AND THE LOW AND TROUGH
IS RESULTING IN S-SW WINDS OF 20-25 KT ACROSS THE FAR NORTHERN
GULF OF CALIFORNIA AND S OF THE TROUGH. THESE WINDS ARE FORECAST
TO DIMINISH TO 20 KT OR LESS EARLY THIS AFTERNOON AS THE LOW
PRES WEAKENS.

A COLD FRONT IS EXPECTED TO REACH THE FAR NW CORNER OF THE AREA
ON MON...EXTENDING FROM 30N134W TO 27N140W ON MON NIGHT AND FROM
30N126W TO 26N130W TO 24N140W BY TUE NIGHT. THE FRONT IS
FORECAST TO DISSIPATE LATE ON WED. FRESH WINDS BEHIND THE FRONT
WILL BRING ANOTHER ROUND OF NW SWELL. EXPECT SEAS BUILDING TO 8-
9 FT IN THE WAKE OF THE FRONT. THIS NW SWELL EVENT WILL
PROPAGATE SE ACROSS THE NW WATERS THROUGH WED.

$$
GR


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