000
AXPZ20 KNHC 130808
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC THU MAR 13 2014

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.                           

...SPECIAL FEATURES...

GULF OF TEHUANTEPEC GALE WARNING...A COLD FRONT IS MOVING 
THROUGH THE SW GULF OF MEXICO THIS MORNING. THE DENSER AIRMASS 
BEHIND THE FRONT WILL FUNNEL ACROSS THE ISTHMUS OF TEHUANTEPEC 
AND INTO THE GULF OF TEHUANTEPEC...DELIVERING NORTHERLY WINDS 
REACHING GALE FORCE STRENGTH WITH SEAS BUILDING AS HIGH AS 15 FT 
BY AFTERNOON. THE WINDS AND SEAS WILL GRADUALLY DIMINISH INTO 
FRI AS THE HIGH PRES BEHIND THE FRONT SHIFTS EASTWARD ACROSS THE 
NORTHERN GULF OF MEXICO. SHORT PERIOD 8 TO 10 FT NE SWELL 
GENERATED FROM THE GALES WILL COVER THE AREA FROM 08N TO 13N 
BETWEEN 95W AND 103W FRI...MIXING WITH LONGER PERIOD NW SWELL. 
THIS WILL DECAY BELOW 8 FT THROUGH FRI NIGHT. LOOKING 
AHEAD...GLOBAL MODELS INDICATE ANOTHER ROUND OF STRONG GAP WINDS 
IN TEHUANTEPEC MONDAY INTO TUESDAY OF NEXT WEEK.

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

A VERY WEAK MONSOON TROUGH EXTENDS FROM 06N85W TO 02N100W. 
SCATTEROMETER DATA AND BUOY OBSERVATIONS INDICATE WINDS ARE 
GENERALLY 5 KT OR LESS ALONG PORTIONS OF THE TROUGH AXIS. THE 
ITCZ EXTENDS FROM 02N105W TO 03N125W. SCATTERED AREAS OF 
MODERATE CONVECTION IS NOTED WITHIN 120 NM EITHER SIDE OF THE 
ALONG THE MONSOON TROUGH BETWEEN 85W AND 100W.

...DISCUSSION... 

IN ADDITION TO THE GALE FORCE GAP WINDS IN THE GULF OF 
TEHUANTEPEC...STRONG WINDS ARE EXPECTED IN THE GULF OF PAPAGAYO 
BY EARLY FRI MORNING. THE HIGH PRES BUILDING BEHIND THE FRONT 
WILL INCREASE THE TRADE WIND FLOW OVER THE SW CARIBBEAN. WITH 
ADDED OVERNIGHT DRAINAGE IMPACTS...THESE WINDS WILL FILTER INTO 
THE GULF OF PAPAGAYO TONIGHT AND AGAIN ON SATURDAY NIGHT WITH 
SEAS BRIEFLY BUILDING TO 8 FT DOWNSTREAM. SIMILARLY A PULSE OF 
FRESH TO STRONG GAP WINDS CAN BE EXPECTED IN THE GULF OF PANAMA 
SAT NIGHT PUSHING SOUTH OF THE AZUERO PENINSULA. 

SCATTERED SHOWERS REMAIN ACTIVE ALONG A VERY WEAK MONSOON TROUGH 
BETWEEN 85W AND 100W. DESPITE LOW LEVEL CONVERGENCE BEING VERY 
WEAK...THE UPPER DIVERGENCE ON THE SE EDGE OF A BROAD NEGATIVELY 
TILTED UPPER TROUGH EXTENDING FROM 20N110W TO 00N105W IS 
MAINTAINING THE SCATTERED CONVECTION. A FEW SHOWERS AND 
THUNDERSTORMS HAD BEEN BRIEFLY ACTIVE ALONG THE UPPER TROUGH 
AXIS NEAR 10N110W NEAR CLIPPERTON ISLAND...BUT THIS HAS SINCE 
DIMINISHED.

FARTHER WEST...A LARGE AREA OF SCATTERED SHOWERS AND A FEW 
THUNDERSTORMS REMAINS ACTIVE FROM 08N TO 16N W OF 135W. THIS IS 
ATTRIBUTABLE TO DIVERGENCE ALOFT ON THE SE SIDE OF A SHARP UPPER 
TROUGH EXTENDING FROM 30N135W TO 10N147W. 

GLOBAL MODELS REMAIN IN DECENT AGREEMENT SHOWING THE NORTHERN 
PORTION OF THE TROUGH MOVING EASTWARD INTO THE BAJA PENINSULA 
THROUGH SATURDAY...CUTTING OFF A WEAKENING UPPER LOW NEAR 
15N135W. THE UPPER LOW WILL KEEP WEATHER UNSETTLED OVER THE DEEP 
TROPICS W OF 130W INTO THIS WEEKEND.
 
A DEEP LAYER RIDGE WILL BUILD N OF 20N W OF 120W FRI AND SAT IN 
THE WAKE OF THE UPPER TROUGH. STRONGER SURFACE HIGH PRES N OF 
THE AREA WILL ALLOW INCREASED TRADE WIND FLOW FROM 07N TO 20N W 
OF 125W FRI AND SAT. 

LOOKING FURTHER AHEAD FOR THE GULF OF CALIFORNIA...THE DEEP 
LAYER RIDGE WILL BUILD OVER THE WESTERN STATES SATURDAY INTO 
SUNDAY...ALLOWING INCREASED NORTHERLY FLOW OVER THE GULF OF 
CALIFORNIA SUNDAY INTO MONDAY.

$$
CHRISTENSEN