000
AXPZ20 KNHC 190218
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                      
0405 UTC TUE APR 19 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0215 UTC.     
  
...INTERTROPICAL CONVERGENCE ZONE...

A PERSISTENT SURFACE LOW OVER NW COLOMBIA TRAILS A SURFACE
TROUGH SW ALONG 06N78W TO 05N88W. A FEW SHOWERS CONTINUE TO
FLARE INTERMITTENTLY ALONG THE TROUGH. 

SCATTEROMETER WINDS INDICATE AN ITCZ FORMS AT 06N90W AND WIGGLES
WSW TO 04N110W...THEN TURNS NW TO 10N124W...THEN TURNS ABRUPTLY
SW THROUGH AN EMBEDDED 1009 MB LOW PRESSURE AT 05N130W WITH THE
ITCZ THEN CONTINUING SW TO BEYOND 04N140W. SCATTERED MODERATE
ISOLATED STRONG CONVECTION IS NOTED WITHIN 150 NM OF LINES FROM
05N88W TO 09N95W AND FROM 07N111W TO 11N116W. SIMILAR CONVECTION
IS OBSERVED WITHIN 90 NM OF LINE FROM 11N124W TO 08N133W. 

...DISCUSSION...
  
N OF 15N E OF 120W... 

A WEAK SURFACE RIDGE EXTENDS FROM NEAR 23N120W TO BEYOND
15N107W. A SURFACE HIGH WILL DEVELOP INTERMITTENTLY ALONG THE
RIDGE NEAR 23N OVER THE NEXT DAY OR SO. SEVERAL WEAK TROUGHS
WILL SWEEP E ACROSS THE WATERS N OF THE RIDGE ON WED AND THU AND
LOSE IDENTITY OVER THE NORTHERN BAJA PENINSULA. THE GRADIENT
WILL TIGHTEN EARLY FRI SUPPORTING STRONG SOUTHERLY FLOW N OF
29.5N AND CONTINUE THROUGH FRI NIGHT. GUIDANCE SUGGESTS STRONG
NORTHERLY DRAINAGE FLOW ACROSS THE GULF OF TEHUANTEPEC ON FRI
NIGHT. 
  
S OF 15N E OF 110W...

NOCTURNAL PULSES OF STRONG ENE WINDS ARE EXPECTED ACROSS...AND
JUST DOWNSTREAM OF THE GULF OF PAPAGAYO LATE TONIGHT...AND AGAIN
LATE WED NIGHT. FRESH N WINDS EXPECTED ACROSS AND DOWNSTREAM OF
THE GULF OF PANAMA EACH NIGHT THROUGH WED NIGHT.
 
LONG PERIOD CROSS-EQUATORIAL SOUTHERLY SWELL IN THE FORM OF 7-8
FT SEAS WILL SPREAD N ACROSS THE EQUATOR BETWEEN 100-110W LATE 
WED THROUGH LATE THU.
 
ELSEWHERE FROM THE EQUATOR TO 32N E OF 140W...

A COLD FRONT EXTENDS FROM 32N129W TO 25N133W THEN IS STALLING TO
NEAR 21N140W. STRONG WESTERLY WINDS ARE NOTED FROM 29-32N W OF
132W WITH LARGE NW SWELL DRIVING SEAS HEIGHTS UP TO 16 FT. THESE
POST-FRONTAL WINDS WILL QUICKLY DIMINISH TO 20 KT OR LESS ON
TUE. ENHANCED SEAS OF 8 FT OR GREATER WILL SPREAD S ACROSS THE
WATERS N OF 19N ON TUE...AND THEN SUBSIDE BELOW 8 FT ON WED. A
SECONDARY COLD FRONT IS ALREADY EVIDENT...BUT IS EXPECTED TO BE
ACCOMPANIED BY ONLY A 10-15 KT WIND SHIFT AS IT REACHES FROM
32N129W TO 28N139W LATE TUE...AND FROM 32N127W TO 26N136W LATE
WED. 

ALTHOUGH NE TRADES ARE EXPECTED TO REMAIN IN THE 15-20 KT RANGE
ACROSS THE TROPICS...EXPECT COMBINED SEAS TO BUILD TO 7-8 FT
NEAR 12N122W BRIEFLY ON TUE.
   
$$
NELSON