000
AXPZ20 KNHC 211603
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE JUN 21 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.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...SPECIAL FEATURES...
HURRICANE BEATRIZ WAS CENTERED NEAR 19.6N 105.5W OR ABOUT 55 NM 
SSE OF CABO CORRIENTES MEXICO MOVING NW OR 310 DEG AT 12 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE HAS RISEN TO 981 MB...WITH 
THE MAXIMUM SUSTAINED WIND SPEED AT 70 KT WITH GUSTS TO 85 KT. 
CONVECTION HAS DIMINISHED CONSIDERABLY IN THE PAST 6 HOURS AS 
BEATRIZ HAS INTERACTED WITH THE MEXICAN COAST. NUMEROUS MODERATE 
ISOLATED STRONG CONVECTION IS CURRENTLY OBSERVED WITHIN 90 NM OF 
THE CENTER...WHILE SCATTERED TO LOCALLY NUMEROUS MODERATE TO 
STRONG CONVECTION WAS OCCURRING IN THE SWLY MONSOONAL FLOW FROM 
12N TO 18.5N BETWEEN 99W AND 110W. DUE TO INTERACTION WITH LAND 
OVERNIGHT...MAXIMUM SEAS HEIGHTS ARE ESTIMATED AT ONLY 19 FT. 
HEAVY RAINFALL AND THE POSSIBILITY OF FLASH FLOODS AND MUDSLIDES 
ARE LIKELY ALONG THE MEXICAN COAST BETWEEN 99W AND 106W. THE 
CYCLONE IS EXPECTED TO TURN MORE TOWARD THE WEST-NORTHWEST AND 
ACCELERATE SLIGHTLY DURING THE NEXT 24 HOURS...TAKING IT OVER 
COOLER SEA SURFACE WATERS BY TONIGHT. THIS WILL LIKELY LEAD TO A 
RAPID DECREASING TREND BY 36 HOURS. SEE THE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC 
FOR MORE DETAILS.
  
...ITCZ/MONSOON TROUGH...
MONSOON TROUGH EXTENDS FROM COSTA RICA NEAR 09N83W TO 12N92W... 
THEN CONTINUES ANEW FROM 14N110W TO 05.5N130W...WHERE IT 
TRANSITIONS TO ITCZ EXTENDING TO 05N135W TO BEYOND 06N140W. 
SCATTERED MODERATE TO STRONG CONVECTION NOTED WITHIN 90 NM N AND 
120 NM S OF AXIS BETWEEN 88W AND 92W. SCATTERED MODERATE 
CONVECTION NOTED WITHIN 120 NM S OF AXIS BETWEEN 110W AND 116W. 

...DISCUSSION...
AN UPPER CYCLONE IS LOCATED WELL W OF THE AREA WITH ITS ENVELOPE 
OF CYCLONIC FLOW EXTENDING E OVER THE DISCUSSION AREA RESULTING 
IN SOUTHERLY FLOW ALOFT TO THE N OF 15N AND W OF 130W. A DEEP 
LAYERED TROUGH ACROSS THE CENTRAL PLAINS EXTENDS S THROUGH TEXAS 
TO A MIDDLE LEVEL CYCLONE OVER N CENTRAL MEXICO NEAR 28N105W 
WITH A MID TO N UPPER TROUGH EXTENDING SW TO 24N114W. AN UPPER 
ANTICYLONE IS CENTERED AT 28N122W WITH A RIDGE EXTENDING N TO 
BEYOND 40N. SE OF THESE FEATURES NE TO E UPPER LEVEL FLOW 
PREVAILS ACROSS THE DEEP TROPICS...WITH THE PULSING DEEP 
CONVECTION OCCURRING NEAR BEATRIZ AND TO ITS SE INDUCING 
DIVERGENT UPPER LEVEL FLOW. 

ELSEWHERE AT THE LOW LEVELS...A BROAD RIDGE COVERS THE AREA N OF 
THE 14N TO THE W OF 118W. THE GRADIENT NE OF THE RIDGE IS 
MAINTAINING NORTHWESTERLY LOW LEVEL FLOW PULSING AT 15 TO 20 KT 
ALONG THE PACIFIC SIDE OF THE BAJA CALIFORNIA PENINSULA THIS 
MORNING...BUT THE GRADIENT IS EXPECTED TO RELAX LATER THIS 
AFTERNOON WITH WINDS DIMINISHING TO LESS THAN 20 KT. A NORTHERLY 
WIND SURGE OF 20 KT WILL DIP S OVER THE MARINE AREA TO THE N OF 
25N BETWEEN 125W AND 135W ON WED NIGHT ACCOMPANIED BY NORTHERLY 
SWELLS WHICH WILL DRIVE COMBINED SEAS UP TO 10 FT FRI ALONG 30N 
BETWEEN 120W AND 130W. 

LOW LEVEL SW MONSOONAL WINDS CONTINUE AROUND 20 KT S OF THE 
MONSOON TROUGH TO 08N BETWEEN 117W AND 100W. LONG PERIOD 
SOUTHERLY SWELLS ARE CONTRIBUTING TO 8 FT SEAS IN THE WATERS S 
OF 08N BETWEEN 117W AND 80W. THIS SW MONSOONAL FLOW IS FORECAST 
TO DIMINISH SOME OVER THE NEXT COUPLE DAYS...WHILE A NEW PULSE 
OF LONG PERIOD SW SWELL MOVES INTO THE AREA TONIGHT THROUGH THE 
REMAINDER OF THE WORK WEEK. 

$$
STRIPLING