Tropical Weather Discussion
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000
AXPZ20 KNHC 272158
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI FEB 27 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2145 UTC.

...SPECIAL FEATURES...

GULF OF TEHUANTEPEC...NORTHERLY 20-30 KT WINDS OBSERVED ACROSS
THE GULF OF TEHUANTEPEC WILL INCREASE TO MINIMAL GALE FORCE THIS
EVENING AND PERSIST THROUGH LATE TONIGHT...WITH SEAS BUILDING TO
A MAX OF 12 FT NEAR 14.5N95W. THE NORTHERLY WINDS WILL DIMINISH
BELOW GALE FORCE EARLY SAT...THEN ARE EXPECTED TO INCREASE TO
MINIMAL GALE FORCE AGAIN LATE SAT AND PERSIST THROUGH LATE SAT
NIGHT BEFORE DIMINISHING BELOW GALE FORCE BY EARLY SUN.
NORTHERLY SURGES ARE THEN EXPECTED TO CONTINUE TO 20-25 KT
THROUGH SUNRISE ON TUE.

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

A LOW LEVEL TROUGH EXTENDS W FROM THE PACIFIC COAST OF COLOMBIA
AT 04N77W TO 04N96W WHERE SCATTEROMETER WINDS INDICATE THAT THE
ITCZ FORMS AND THEN CONTINUES NW TO AN EMBEDDED TROUGH AT
08N117W THEN CONTINUES W TO BEYOND 08N140W. SCATTERED MODERATE
CONVECTION IS OBSERVED WITHIN 30 NM OF 06N83W...WITHIN 90 NM
EITHER SIDE OF A LINE FROM 04N78W TO 03N90W AND WITHIN 180 NM
EITHER SIDE OF A LINE FROM 06N117W TO 10N126W TO 08N140W.

...DISCUSSION...

A POSITIVE TILT UPPER TROUGH EXTENDS SW FROM OVER ARIZONA TO A
BASE OVER THE DEEP TROPICS AT 09N135W. AN UPPER RIDGE EXTENDS W
FROM THE SW CARIBBEAN OVER COLOMBIA ACROSS THE TROPICS TO A ILL-
DEFINED CREST NEAR 05N105W. UPPER DIFFLUENCE BETWEEN THE TROUGH
AND THE RIDGE IS ENHANCING THE ITCZ RELATED CONVECTION
PREVIOUSLY DESCRIBED. THE RESULTANT DEBRIS MOISTURE IS ADVECTED
NE CONCENTRATING INTO INTO A 500 NM WIDE PLUME THAT CONTINUES
ENE ACROSS CENTRAL MEXICO...THE GULF OF MEXICO AND ACROSS MOST
OF FLORIDA. DEBRIS MOISTURE FROM THE SMALL CLUSTERS OF
CONVECTION DESCRIBED ALONG THE EASTERN PORTION OF THE ITCZ
QUICKLY EVAPORATES IN THE DRY UPPER AIR DOMINATING THE TROPICS
TO THE E OF 106W.

A SURFACE RIDGE EXTENDS FROM 32N137W TO 20N110W. A BROAD MIX OF
SWELLS HAS RESULTED COMBINED SEAS OF 7-10 FT ACROSS THE PACIFIC
WATERS W OF 133W. THE SWELLS WILL GRADUALLY SUBSIDE BELOW 8 FT
TONIGHT. NORTHERLY WINDS TO THE NE OF THE RIDGE ARE CURRENTLY
SUBSIDING TO NW AT 10-15 KT...BUT THE ASSOCIATED NW SWELLS WILL
REACH THE PACIFIC COAST OF THE NORTHERN BAJA PENINSULA IN THE
FORM OF 5-8 FT SEAS. THESE SEAS ARE EXPECTED TO SUBSIDE TO 4-6
FT ON SAT. GUIDANCE INDICATES THAT A BATCH 20-25 KT NORTHERLY
WINDS...WITH 8-11 FT SEAS...WILL MOVE INTO THE NORTHERN WATERS
BETWEEN 125-135W ON SAT NIGHT...AND SHIFT SW TO ALONG 22N ON SUN
NIGHT.

GULF OF CALIFORNIA...S-SW 10-15 KT WINDS CURRENTLY OBSERVED
OVER THE NORTHERN GULF OF CALIFORNIA WILL INCREASE TO 20-25 KT
TONIGHT...AND CONTINUE THROUGH SAT NIGHT...THEN RELAX TO 10-15
KT AHEAD OF A WEAK TROUGH ARRIVING IN THE NORTHERN GULF ON MON
NIGHT. THE TROUGH WILL PASS THROUGH THE CENTRAL GULF OF
CALIFORNIA ON TUE WITH ONLY A 5-10 KT SW-W-NW WIND SHIFT.

GULF OF PAPAGAYO...NOCTURNAL 20-25 KT NE SURGES ARE EXPECTED TO
RESUME TONIGHT...WITH A SIGNIFICANT EVENT OCCURRING ON SUN AND
MON NIGHTS.

.GULF PANAMA...NORTHERLY 10-15 KT WINDS EXPECTED EACH NIGHT TILL
MON NIGHT WHEN GUIDANCE IS SUGGESTING AN INCREASE TO 20-25 KT.


$$
NELSON



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