000
AXPZ20 KNHC 202204
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON JUN 20 2011

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.

...SPECIAL FEATURES...
TROPICAL STORM BEATRIZ IS CENTERED NEAR 17.0N 103.1W AT 20/2100 
UTC OR ABOUT 80 NM SW OF LAZARO CARDENAS MEXICO MOVING NNW OR 
330 DEG AT 07 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 989 MB. 
MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 KT. BASED 
ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2115 
UTC NUMEROUS MODERATE SCATTERED STRONG CONVECTION LIES WITHIN 90 
NM W SEMICIRCLE OF THE CENTER. BEATRIZ IS FORECAST TO BECOME A 
HURRICANE TONIGHT AS IT CONTINUES ON A NW TRACK PARALLELING THE 
MEXICAN COAST. SEE THE LATEST NHC FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS.
  
...ITCZ/MONSOON TROUGH...
MONSOON TROUGH FROM 10N85W TO SE OF TROPICAL STORM BEATRIZ AT 
14N100W THEN CONTINUES FROM 14N105W TO 06N125W. ITCZ EXTENDS 
FROM 06N140W. ASIDE FROM CONVECTION NOTED WITH TROPICAL STORM 
BEATRIZ...SCATTERED MODERATE ISOLATED STRONG WITHIN 120 NM N 
SIDE OF MONSOON TROUGH BETWEEN 95W TO 102W.

...DISCUSSION...
A LARGE AREA OF FRESH TO STRONG SW WINDS ARE NOTED IN ASCAT DATA 
CONVERGING INTO THE STORM...MAINLY N OF 08N BETWEEN 95W AND 
115W. SEAS ARE LIKELY REACHING UP TO 13 FT IN THE AREA OF THE 
FRESH TO STRONG SW FLOW...LARGELY IN SW SWELL WITH PERIODS UP TO 
10 SECONDS. THIS FLOW IS PUSHING TOWARD THE COASTLINE OF THE 
MEXICAN STATES OF OAXACA AND GUERRERO. MODERATE TO STRONG 
CONVECTION IS ALSO NOTED ALONG AND OFFSHORE OF THE COAST IN 
GUERRERO WHERE THE MOIST SW FLOW IS CONVERGING INTO THE COAST.

FURTHER SOUTH...SOUTHERLY CROSS-EQUATORIAL FLOW IS MOVING INTO 
THE AREA MAINLY SOUTH OF 05N W OF 110W. THE WAVEWATCH III AND 
ECWAVE MODELS WERE SLIGHTLY HIGH IN THEIR INITIALIZATIONS OF 
THIS SWELL COMPARED TO ALTIMETER DATA FROM EARLIER...BUT THE 
GENERAL FORECAST REMAINS THE SAME WITH SOUTHERLY FLOW OF 8 TO 9 
FT MOVING N OF THE EQUATOR AS FAR AS 10N BY LATE TUE.

FURTHER WEST...SURFACE HIGH PRES N OF THE AREA IS WEAKENING AS A 
COLD FRONT MOVES INTO THE NE PACIFIC. THIS IS RESULTING IN A 
FAIRLY WEAK PRES GRADIENT W OF 110W...EQUATING TO MODEST TRADE 
WIND FLOW. DEEP LAYER MOISTURE REMAINS LIMITED W OF 120W...AND 
NO SIGNIFICANT CONVECTION IS NOTED.

$$
CHRISTENSEN