000
AXPZ20 KNHC 161519
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC FRI JAN 16 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC. 

...SPECIAL FEATURES...                                       

GULF OF TEHUANTEPEC GALE WARNING...STRONG NORTHERLY FLOW  
BETWEEN A COLD FRONT APPROACHING THE YUCATAN PENINSULA IN THE 
GULF OF MEXICO TO THE N AND STRONG RIDGING ALONG THE EASTERN 
MEXICAN COAST CONTINUES TO FUNNEL THROUGH THE ISTHMUS OF 
TEHUANTEPEC AND ACROSS THE GULF OF TEHUANTEPEC. WINDS ARE
30 TO 40 KT IN THE GULF OF TEHUANTEPEC EARLY THIS MORNING...BUT 
WILL DIMINISH TO 30-35 KT BY THE EARLY AFTERNOON HOURS. 
THEREAFTER...THE RIDGING ACROSS THE WESTERN GULF OF MEXICO 
BEGINS TO WEAKEN AND WINDS WILL DIMINISH BELOW GALE FORCE JUST 
AFTER SUNRISE SAT...WITH A SMALL POCKET OF FRESH TO STRONG 
NORTHERLY WINDS THEN PERSISTING IN THE IMMEDIATE GULF OF 
TEHUANTEPEC THROUGH SUN MORNING. THE LATEST TAFB-NWPS MODEL 
GUIDANCE INDICATES SEAS UP TO 17 FT WHILE THE LATEST MWW3 SHOWS 
SEAS UP TO 15 FT. SEAS WILL SUBSIDE TO 8-12 FT OVERNIGHT TONIGHT 
INTO EARLY SAT...THEN TO 8-10 FT OVERNIGHT SAT INTO EARLY SUN. 
THE NEXT ROUND OF GALE FORCE WINDS START SUN EVENING INTO MON 
MORNING.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           

THE MONSOON TROUGH AXIS EXTENDS FROM 06N77W TO 05N84W TO  
06N92W. THE ITCZ AXIS EXTENDS FROM 06N92W TO 05N101W TO 09N115W 
THEN RESUMES FROM 08N120W TO 06N140W. SCATTERED MODERATE AND  
ISOLATED STRONG CONVECTION IS FROM 02N TO 08N E OF 80W. 
SCATTERED MODERATE CONVECTION IS FROM 04N TO 06N BETWEEN 80W  
AND 84W...FROM 01N TO 03N BETWEEN 81W AND 83W...AND FROM 07N TO 
09N BETWEEN 116W AND 119W.
 
...DISCUSSION...                                                 

THE SUBTROPICAL RIDGE EXTENDS FROM A 1025 MB HIGH NEAR 32N129W 
SE TO 24N113W AND ALSO SW FROM THE HIGH TO NEAR 26N140W. LOW 
PRESSURE HAS DEVELOPED NEAR 16N118W AT 1008 MB AND IS MOVING TO 
THE NW AROUND 10 KT. THIS LOW IS ASSOCIATED WITH MIDDLE TO UPPER 
LEVEL ENERGY NOTED ON WATER VAPOR IMAGERY WITHIN A BROAD DEEP 
LAYERED TROUGH BETWEEN 108W AND 128W. THIS TROUGHING ALOFT HAS 
CUT OFF A DEEP LAYER LOW NEAR 16N124W WHICH WILL DRIFT E-SE 
THROUGH EARLY NEXT WEEK. THE PRESSURE GRADIENT BETWEEN THE 
SURFACE LOW AND THE FAIRLY STATIONARY SUBTROPICAL RIDGE TO THE N 
WILL BE STRONG ENOUGH TO SUPPORT 20-30 KT WINDS ON THE NORTHERN 
PERIPHERY OF THE LOW CENTER BUILDING SEAS UP TO 12 FT.

A SURROUNDING AREA OF PRIMARILY NW SWELL AT 8-11 FT COVERS THE 
WATERS FROM 12N TO 24N W OF 120W AND FROM 14N TO 20N W OF 114W 
WHICH WILL DECAY SLIGHTLY AND BECOME CONFINED TO THE WATERS W OF 
120W-125W BY SUN MORNING.

GULF OF PAPAGAYO...SHARP AND STRONG RIDGING ACROSS CENTRAL 
AMERICA IS SUPPORTING FRESH TO STRONG NE-E WINDS IN AND DOWNWIND 
OF PAPAGAYO BUILDING SEAS UP TO 8-9 FT. WINDS WILL CONTINUE TO 
PULSE TO 20-25 KT DURING THE NIGHT AND EARLY MORNING HOURS 
THROUGH 48 HOURS...BRIEFLY INCREASING TO 30 KT DURING THE PERIOD 
OF MAXIMUM NOCTURNAL DRAINAGE FLOW JUST BEFORE SUNRISE...WITH   
A BRIEF LULL OF WINDS DIMINISHING TO 20 KT OR LESS DURING THE 
AFTERNOON HOURS.

GULF OF PANAMA...FRESH TO LOCALLY STRONG NORTHERLY WINDS ARE 
PRESENT IN THE WESTERN GULF OF PANAMA AND S OF THE AZUERO 
PENINSULA DUE TO A TIGHT PRESSURE GRADIENT ACROSS THE AREA. 
WINDS WILL DIMINISH BY EARLY THIS AFTERNOON AS THE GRADIENT 
TEMPORARILY SLACKENS...THEN WILL RETURN THIS EVENING INTO EARLY 
SAT BEFORE DIMINISHING AGAIN. SEAS OF 4-6 FT WILL BUILD TO 5-7 
FT THIS EVENING INTO EARLY SAT.
 
GULF OF CALIFORNIA...A SLOW MOVING POSITIVELY TILTED UPPER LEVEL 
TROUGH WILL MOVE EASTWARD THROUGH THE SW UNITED STATES. AT    
THE SURFACE...THE PRESSURE GRADIENT WILL BUILD BETWEEN LEE SIDE 
TROUGHING ALONG THE W SLOPES OF THE SIERRA MADRE OCCIDENTAL AND 
INCREASED RIDGING OVER THE GREAT BASIN IN THE WAKE OF THE UPPER 
TROUGH. FRESH TO STRONG NW-N WINDS IN THE GULF N OF 29.5N WILL 
DIMINISH THIS AFTERNOON AS THE UPPER TROUGH LIFTS OUT FROM THE 
AREA WITH THE PRESSURE GRADIENT AT THE SURFACE LOOSENING.

$$
LEWITSKY