Tropical Weather Discussion
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000
AXPZ20 KNHC 030342
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE MAR 03 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 ITCZ EXTENDS FROM 04N86.5W TO 08N121W TO BEYOND 06N140W.
SCATTERED MODERATE CONVECTION NOTED WITHIN 90 NM EITHER SIDE OF
AXIS BETWEEN 86.5W AND 90W...AND WITHIN 60 NM EITHER SIDE OF
AXIS BETWEEN 125W AND 133W. SCATTERED MODERATE CONVECTION NOTED
WITHIN 180 NM EITHER SIDE OF TROUGH FROM 15N118W TO 18N117W TO
24N114W.

...DISCUSSION...

A DEEP LAYERED MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM
WEAKENING UPPER CYCLONE NEAR 35N122W TO 16N126W...WITH
REINFORCING ENERGY CONTINUING TO DIVE SOUTHWARD ACROSS THE W
SIDE OF THE TROUGH...MAINTAINING A MEAN POSITION OF THE BROADER
PERSISTENT TROUGH BETWEEN 117W AND 140W. THE UPPER TROUGH
SUPPORTS A COLD FRONT MOVING GRADUALLY SE ACROSS THE AREA FROM
30N112W TO 24N114W TO 20N120W. THE COLD FRONT EXTENDS ACROSS THE
CENTRAL GULF OF CALIFORNIA...WITH MODERATE S TO SW WINDS
OCCURRING N OF 25N AHEAD OF THE FRONT...AND SW TO W WINDS 15 TO
20 KT PREVAILING ACROSS PORTIONS N OF 30N. THE FRONT IS EXPECTED
TO CONTINUE SHIFTING GRADUALLY SE AND MOVE THROUGH THE FULL
LENGTH OF THE GULF OF CALIFORNIA BY WED BEFORE STALLING JUST SE
OF MAZATLAN. WINDS AND SEAS ON BOTH SIDES OF THE FRONT WILL
GRADUALLY DIMINISH OVERNIGHT. MEANWHILE...STRONG SW FLOW THROUGH
THE MIDDLE AND UPPER LEVELS OCCURRING SE OF THE TROUGH IS
DIRECTLY OVERHEAD OF THE SURFACE TROUGH MENTIONED ABOVE AND THE
COLD FRONT AND CONTINUES TO ENHANCE CONVECTION WITHIN 180 NM
EITHER SIDE OF THE TROUGH....WITH ASSOCIATED UPPER CLOUDS AND
LIGHT TO MODERATE RAIN SPREADING NE ACROSS THE S HALF OF THE
BAJA PENINSULA AND ACROSS NW MEXICO.

A 1034 MB HIGH BEHIND THE FRONT EXTENDS FROM THE NE PACIFIC NEAR
40N142W SOUTHWARD THEN SE ACROSS THE AREA TO NEAR 25N118W.
AFTERNOON SCATTEROMETER DATA SHOWED AN AREA OF FRESH TO STRONG
NE TRADEWINDS FROM 16N TO 22N W OF 133W...INDUCED BY THE PRES
GRADIENT BETWEEN THE HIGH AND THE ITCZ TO THE SOUTH. MODEL
GUIDANCE INDICATES THAT THIS REGION OF ENHANCED TRADES WILL
SHIFT W-SW BEYOND 140W THROUGH TUE.

GAP WIND FLOW DOMINATES THE FORECAST AREA E OF 120W...WITH ALL
THE TYPICAL GAP AREAS SEEING MODERATE TO FRESH FLOW SPILLING
ACROSS CENTRAL AMERICA INTO THE EASTERN PACIFIC FROM THE
CARIBBEAN. MOST OF THESE LOCATIONS WILL SEE PEAK WINDS DUE TO
NOCTURNAL DRAINAGE FLOW DURING LATE NIGHT AND EARLY MORNING
HOURS THROUGH EARLY WED.

GULF OF TEHUANTEPEC...FRESH TO STRONG NORTHERLY WINDS CURRENTLY
OBSERVED THROUGH AND DOWNSTREAM OF THE GULF WILL PULSE TO 30 KT
AGAIN TONIGHT...WITH SEAS TO 10-11 FT BY EARLY TUE
MORNING...THEN GRADUALLY DIMINISH TO LESS THAN 15 KT BY EARLY
WED. THE NEXT SIGNIFICANT GAP WIND EVENT HERE IS FORECAST TO
BEGIN LATE THU...AS A STRONG COLD FRONT MOVES ACROSS THE W GULF
OF MEXICO...AND WINDS QUICKLY INCREASE TO A STRONG GALE THU
NIGHT AND REACH NEAR STORM FORCE EARLY FRI.

THE GULF OF PAPAGAYO...FRESH TO STRONG NE WINDS WILL CONTINUE...
WITH NOCTURNAL PULSES REACHING 25-30 KT TONIGHT AND 20-25 KT TUE
NIGHT. FRESH NE WINDS ALSO LIKELY IN AND DOWNWIND OF THE GULF OF
FONSECA EACH NIGHT DURING THE NIGHT TIME MAX ACROSS PAPAGAYO.

THE GULF OF PANAMA...NORTHERLY WINDS 15-25 KT ARE EXPECTED TO
PREVAIL ACROSS THE GULF AND DOWNSTREAM TO NEAR 05N FOR THE NEXT
24-48 HOURS...WHERE SEAS WILL BUILD 8-9 FT THROUGH TUE NIGHT.

$$
STRIPLING


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