Hurricane Advisories Hurricane advisories

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI JAN 27 2012

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
0315 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH EXTENDS FROM LOW PRES NEAR 07N73W 1005 MB TO
04N79W TO 06N82W TO 05N92W...WHERE IT TRANSITIONS TO ITCZ
AXIS... CONTINUING ON TO 05N104W TO 07.5N113W TO 05N140W.
SCATTERED MODERATE TO STRONG FROM 06.5N TO 12N BETWEEN 105W AND
113W. SCATTERED MODERATE ISOLATED STRONG WITHIN 60-120 NM EITHER
SIDE OF AXIS BETWEEN 114W AND 136W.

...DISCUSSION...
A BROADENING UPPER LEVEL TROUGH CONTINUES TO DOMINATE THE FAR NE
PORTIONS OF THE AREA...WITH TROUGH AXIS EXTENDING FROM THE
CENTRAL U.S. ALONG 91W/92W...S-SW ACROSS NW LOUISIANA AND
THROUGH SE TEXAS TO NEAR THE W COAST OF MEXICO NEAR 20N107W. AN
ELONGATED MIDDLE TO UPPER LEVEL CYCLONE CONTINUED ACROSS FAR W
PORTIONS OF THE AREA...CENTERED NEAR 23N140W...EXTENDING S THEN
S-SE TO NEAR 08N134W...AND REMAINS CUT OFF FROM THE MEAN UPPER
LEVEL FLOW. IN BETWEEN THESE TWO TROUGHS WAS A WEAKENING UPPER
LEVEL RIDGE CENTERED ON A MIDDLE LEVEL ANTICYCLONE NEAR 29N127W.
A VERY SHARP AND HIGH AMPLITUDE UPPER TROUGH ACROSS THE CENTRAL
PACIFIC IS FORECAST TO SHIFT E TOWARDS W PORTIONS OF THE AREA
FRI AND SAT AND WILL AID IN KICKING OUT THE CUT OFF LOW AND
REORGANIZING THE UPPER LEVEL FLOW ACROSS THE AREA THROUGH EARLY
NEXT WEEK.

THE SURFACE HIGH PRES RIDGE DOMINATING W PORTIONS OF THE AREA
THE PAST SEVERAL DAYS IS GRADUALLY WEAKENING...WITH A COLLAPSING
1029 MB HIGH CURRENTLY CENTERED NEAR 35N133W...WITH RIDGE
COVERING THE AREA N OF 15N W OF 108W. TRADEWINDS ACROSS THE
SOUTH THROUGH SOUTHEAST PERIPHERY OF THE RIDGE HAVE BEGUN TO
SHRINK IN AREAL COVERAGE...WITH NE TRADEWINDS AT 20 KT FROM 07N
TO 13N W OF 127W...AND NE TO E WINDS 20-25 KT N OF 20N W OF
132W. COMBINED SEAS ACROSS THIS AREA ARE RUNNING 8 TO 12 FT IN
MIXED NE WIND SWELL AND LONG PERIOD NW SWELL. N TO NE WINDS
PRESENTLY DOMINATE NE PORTIONS OF THE AREA TO 121W AT 20-25
KT...WHERE RECENT ALTIMETER MEASUREMENTS VERIFIED SEAS 9 TO 14
FT. THE FRESH TRADES N OF THE ITCZ CONTINUE TO GENERATE A
SIGNIFICANT CLUSTER OF SCATTERED MODERATE TO DEEP CONVECTION
MENTIONED ABOVE BETWEEN 114W AND 136W...WHICH IS BEING AIDED BY
A SHORT WAVE MOVING NE THROUGH THE BASE OF THE UPPER TROUGH
ALONG 140W. THIS PERSISTENT REGION OF DEEP CONVECTION OF THE
PAST SEVERAL DAYS HAS BEGUN TO CREATE IT'S OWN UPPER ANTICYCLONE
NEAR 06N119W. OTHERWISE...LARGE NWLY SWELLS PREVAIL ACROSS MUCH
OF THE AREA N OF 10N W OF 115W.

A STRONG COLD FRONT IS MOVING ACROSS THE CENTRAL GULF OF MEXICO
EARLY THIS EVENING...EXTENDING FROM THE FLORIDA PANHANDLE TO THE
CENTRAL BAY OF CAMPECHE. STRONG HIGH PRES BUILDING BEHIND THE
FRONT WILL TIGHTEN THE PRES GRADIENT OVER SOUTHERN MEXICO THIS
EVENING AND TONIGHT...AND RESULT IN GALE FORCE WINDS THROUGH THE
GULF OF TEHUANTEPEC DURING THE NEXT SEVERAL HOURS. THIS GALE
EVENT IS FORECAST TO BE SHORT LIVED...WITH WINDS BELOW GALE
FORCE EXPECTED BY FRI EVENING.

$$
STRIPLING