000
AXPZ20 KNHC 040925
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1005 UTC SUN JAN 4 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC. 

...SPECIAL FEATURE...

GULF OF TEHUANTEPEC STORM WARNING...STRONG HIGH PRES BEHIND A 
COLD FRONT ACROSS THE SW GULF OF MEXICO WILL PLUNGE SOUTHWARD 
INTO SOUTHERN MEXICO THIS AFTERNOON. COLD DENSE AIR BEHIND THE 
FRONT WILL FUNNEL THROUGH THE CHIVELA PASS INTO THE GULF OF 
TEHUANTEPEC THIS EVENING AND INTENSIFY OVERNIGHT. GAP WINDS WILL 
RAPIDLY INCREASE TONIGHT. BOUNDARY LAYER MODEL GUIDANCE SHOWS 
HIGHEST WINDS PEAKING AT 45-50 KT LATER TONIGHT. MAX WINDS WILL 
CONTINUE DURING LATE NIGHT AND EARLY MORNING HOURS FOR SEVERAL 
DAYS...REMAINING STEADY GALE FORCE THROUGH AT LEAST THU. THIS 
LONG STRETCH OF VERY STRONG WINDS WILL PRODUCE UNUSUALLY LARGE 
AREA OF SEAS 12 FT OR GREATER MON THROUGH WED AIDED BY STRONG 
PAPAGAYO WIND EVENT MENTIONED BELOW. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
             
MONSOON TROUGH EXTENDS FROM 06N77W TO 06N91W. ITCZ EXTENDS FROM 
06N91W TO 07N118W...THEN RESUMES FROM 07N122W TO 07N140W. NO 
SIGNIFICANT CONVECTION.

...DISCUSSION...                                                 

989 MB LOW PRES NW OF THE AREA NEAR 35N150W EXTENDS A COLD FRONT 
SOUTHWARD TO 25N146W TO 15N145W. THE LOW WILL MOVE N AND BECOME 
OCCLUDED THE NEXT TWO DAYS. STRONG NEGATIVELY TILTED SHORT WAVE 
WILL REINFORCE THE DEEP LAYER TROUGH SUPPORTING THE FRONT. WINDS 
WILL INCREASE TO 30 KT IN NW WATERS N OF 20N W OF 135W TODAY AND 
REMAIN NEAR GALE FORCE AS THE OCCLUDING FRONT APPROACHES MON. NW 
SWELL WILL OUTRUN THE FRONT...WITH SEAS INCREASING TO 16 FT MON 
MORNING. WIDESPREAD SHOWERS...AND A FEW TSTMS...W OF 140W AHEAD 
OF THE FRONT WILL SWEEP INTO NW WATERS TODAY. 

A SUBTROPICAL RIDGE EXTENDS FROM 1026 MB HIGH PRES N OF THE AREA 
NEAR 39N126W TO THE SOUTHERN TIP OF THE BAJA CALIFORNIA 
PENINSULA. THE PRES GRADIENT BETWEEN THE RIDGE AND THE ITCZ IS 
SUPPORTING A LARGE AREA OF MODERATE TO FRESH TRADE WINDS W OF 
115W. THE SUBTROPICAL RIDGE SHOULD SHIFT SLIGHTLY E AS THE COLD 
FRONT IN THE CENTRAL PACIFIC MAKES ITS WAY EASTWARD. THIS WILL 
EXPAND THE AREA OF MODERATE TO FRESH TRADES EASTWARD AS WELL AS 
THE AREA OF 8-10 FT SEAS IN MIXED NW AND EASTERLY SWELL FOUND N 
OF THE ITCZ. 

SCATTEROMETER DATA SHOWS LARGE AREA OF FRESH TRADE WINDS FROM 
10N TO 23N W OF 115W. EXPECT LITTLE SIGNIFICANT CHANGE TO THE 
SYNOPTIC PATTERN IN THE DEEP TROPICS THE NEXT FEW DAYS...WITH 
MODERATE TO FRESH TRADES PRODUCING LARGE AREA OF 8-9 FT SEAS IN 
MIXED NW AND EASTERLY SWELL N OF CONVERGENCE ZONE W OF 115-120W. 

GAP WINDS...
                                                   
GULF OF PAPAGAYO...HIGH PRES N OF THE SW CARIBBEAN ALONG WITH 
LOCAL OVERNIGHT DRAINAGE EFFECTS WILL SUPPORT PULSES OF FRESH TO 
STRONG GAP WINDS WITH SEAS TO 10 FT THROUGH EARLY MON. THE GAP 
WIND EVENT WILL INTENSIFY MON MORNING AND CONTINUE THROUGH AT 
LEAST THU WITH MAX WINDS EACH MORNING IN EXCESS OF 30 KT. THIS 
WILL GENERATE AN AREA OF 8-12 FT SEAS WITH EACH STRONG PULSE TO 
SPREAD WEST AND COMBINE WITH HIGH SEAS GENERATED BY TEHUANTEPEC.

GULF OF CALIFORNIA...HIGH PRES WILL BUILD IN THE GREAT BASIN N 
OF THE AREA LATER TODAY. GRADIENT BETWEEN THE HIGH AND TROUGHING 
W OF SIERRA MADRE OCCIDENTAL WILL INDUCE 20-25 KT NW FLOW IN THE 
GULF OF CALIFORNIA N OF 25N THIS EVENING. WINDS AND SEAS WILL 
DIMINISH TO 20 KT OR LESS AND SEAS LESS THAN 8 FT MON MORNING. 

$$
MUNDELL