000
AXPZ20 KNHC 192113
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                        
2205 UTC TUE MAR 19 2013

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 
2030 UTC.

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

MONSOON TROUGH AXIS EXTENDS FROM 08N84W TO 06N90W. ITCZ AXIS 
CONTINUES FROM 06N90W TO 05N103W TO 02N120W TO 03N140W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FROM 04N TO 06N 
BETWEEN 83W AND 95W...AND FROM 02N TO 04N BETWEEN 127W AND 133W. 
ISOLATED MODERATE CONVECTION IS FROM 02N TO 07N BETWEEN 106W AND 
110W. 

...DISCUSSION...                                                

A LONG WAVE TROUGH EXTENDS FROM WELL NE OF THE REGION SWWD 
THROUGH NE MEXICO TO A DEVELOPING UPPER LOW AT 15N116W THEN 
CONTINUES SE TO NEAR 03N110W. UPPER DIVERGENCE E OF THE TROUGH 
IS ENHANCING CONVECTION ASSOCIATED WITH THE ITCZ AS DESCRIBED 
ABOVE. TO THE W OF THE TROUGH...HIGHLY AMPLIFIED UPPER RIDGING 
DOMINATES THE WEST PORTION OF THE FORECAST AREA. THE TROUGH IS 
FORECAST TO LIFT NE THROUGH THU LEAVING BEHIND THE UPPER LOW... 
WHICH WILL MOVE ESE. ANOTHER RIDGE IS NOTED IS OF 95W.

AT THE SURFACE...A 1022 MB HIGH CENTER IS N OF THE AREA AT 
32N125W WITH A RIDGE SE TO NEAR 19N110W. HIGH PRES COVERS THE 
AREA N OF 18N. THE WEAKER PRES GRADIENT ON THE SOUTHERN 
PERIPHERY OF THIS RIDGE IS ONLY ALLOWING FOR WEAK NE TRADE WINDS 
OF ABOUT 15-20 KT TO PERSIST ACROSS THE CENTRAL AND WESTERN 
PORTIONS OF THE DISCUSSION AREA. A COLD FRONT HAS REACHED THE 
FAR NW CORNER OF THE AREA AND NOW EXTENDS FROM 30N138W TO 
27N140W. THE FRONT IS FORECAST TO DISSIPATE OVER THE NW WATERS 
BY WED. WINDS OF 20 KT OR LESS AND SEAS TO AROUND 8 FT ARE 
NOTED IN THE WAKE OF THE FRONT. 

SEAS OF 8 FT DUE TO PRIMARILY A SW SWELL COMPONENT ARE CONFINED 
03N TO 10N BETWEEN 114W AND 128W. THE AREA OF SWELLS AND NE 15-
20 KT TRADE WINDS IS FORECAST TO MOVE WWD OVER THE NEXT 48 HRS 
AS THE HIGH CENTER N OF THE AREA SHIFTS SW. THIS SYSTEM WILL BE  
REPLACED BY A BIT STRONGER HIGH PRES LATE WED INTO THU...WITH 
THE NEW RIDGE MAINLY DOMINATING THE WATERS N OF 10N W OF 115W BY 
THU.  

$$
GR