000
AXPZ20 KNHC 182127
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
2205 UTC MON MAY 18 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 
2115 UTC.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N104W TO 
05N112W TO 08N121W TO 04N140W. SCATTERED MODERATE CONVECTION IS 
FROM 01N TO 06N BETWEEN 121W AND 135W...AND FROM 09N TO 14N 
BETWEEN 117W AND 123W.

...DISCUSSION...                                                
A MIDDLE TO UPPER LEVEL LOW IS CENTERED WELL NORTH OF THE 
DISCUSSION AREA NEAR 47N151W WITH AXIS EXTENDING S-SE TO A BASE 
NEAR 36N144W. THIS TROUGHING SUPPORTS A WEAK COLD FRONT ENTERING 
THE AREA NEAR 32N129W TO 29N130W TO 25N140W WITH POSSIBLE 
ISOLATED SHOWERS OCCURRING WITHIN 60 NM EITHER SIDE. WHILE A 
SUBTLE WIND SHIFT IS PRESENT ON RECENT SCATTEROMETER DATA...SEAS 
TO THE NW OF THE FRONT REMAIN IN THE 5 TO 7 FT RANGE AND ARE 
EXPECTED TO CONTINUE SUBSIDING THROUGH TUESDAY.

OTHERWISE...THE REMAINDER OF THE NORTHERN WATERS N OF 15N ARE 
UNDER THE INFLUENCE OF A WEAK SURFACE RIDGE WITH AXIS EXTENDING 
FROM 28N127W SE TO 16N115W WITH GENERALLY MODERATE TO FRESH NE 
TRADES OCCURRING TO THE SOUTHWEST OF THE RIDGE AXIS. SEAS ACROSS 
THIS AREA ARE IN THE RANGE OF 5 TO 7 FT...GENERALLY HIGHER S OF 
20N. NEAR THE BAJA CALIFORNIA COAST...THE PRESSURE GRADIENT 
BETWEEN THE RIDGE AND LOWER PRESSURE ACROSS THE GULF OF 
CALIFORNIA AND NORTHWESTERN MEXICO IS GENERATING A MODERATE 
NORTHWESTERLY BREEZE ALONG MOST OF THE PACIFIC COASTAL WATERS OF 
THE BAJA CALIFORNIA PENINSULA. THE PRESSURE GRADIENT IS EXPECTED 
TO STRENGTHEN SLIGHTLY THIS EVENING AND AGAIN TUESDAY AFTERNOON 
AS THE AFOREMENTIONED UPPER LEVEL TROUGH MOVES OVER THE BAJA 
CALIFORNIA REGION. GIVEN THIS SYNOPTIC SETUP...NW WINDS ARE 
FORECAST TO BRIEFLY REACH 20-25 KT THIS EVENING N OF 25N WITHIN 
60 NM OF THE COAST OF BAJA CALIFORNIA...AND AGAIN TUESDAY 
EVENING WITH SEAS TO 8 FT.

WITHIN THE DEEP TROPICS...A FEW WEAK PERTURBATIONS ARE NOTED 
WITHIN THE ITCZ REGION W OF 105W...ONE AS A SURFACE TROUGH 
ANALYZED FROM 12N128W TO 05N130W. MOST CONVECTION WITH THIS 
FEATURE REMAINS EMBEDDED WITHIN THE ITCZ AXIS TO THE S OF 06N. 
THE OTHER WEAK AREA OF WESTWARD MOVING ENERGY IS NEAR 10N121W 
AND WILL LIKELY MERGE WITH THE WESTERN SURFACE TROUGH LATE 
TUESDAY INTO EARLY WEDNESDAY BETWEEN 130W AND 140W.

ACROSS THE EASTERN PORTION OF THE DEEP TROPICS...THE MONSOON 
TROUGH IS NOT EVIDENT WITH GENERALLY LIGHT TO GENTLE WINDS 
OCCURRING FROM THE EQUATOR TO 10N E OF 105W. AN EARLIER ASCAT 
PASS AROUND 18/1506 UTC INDICATED FRESH TO OCCASIONAL STRONG N 
TO NE WINDS THROUGH THE GULF OF PAPAGAYO...HOWEVER THIS PULSE 
HAS LIKELY WEAKENED WITH ANOTHER PULSE ANTICIPATED EARLY TUESDAY 
MORNING TO 25 KT AND SEAS TO 8 FT FROM 10N TO 11.5N E OF 88W. 
THE PULSE EARLY WEDNESDAY MORNING IS EXPECTED TO BE SLIGHTLY 
WEAKER AND REMAIN 20 KT OR LESS WITH SEAS LESS THAN 8 FT.

LOOKING AHEAD...ANOTHER STRONG SOUTHERN HEMISPHERIC SW SWELL 
WILL MOVE INTO THE REGIONAL WATERS LATE IN THE WEEK. SEAS WILL 
BUILD TO 8 FT AND GREATER ALONG THE EQUATORIAL WATERS BY THU 
MORNING. THIS PULSE OF LONG PERIOD SWELL IS EXPECTED TO REACH 
THE COASTLINES OF CENTRAL AMERICA BY LATE FRI...AND COULD BRING
ROUGH SEA STATE CONDITIONS TO THOSE AREAS.
 
$$
HUFFMAN