000
AXPZ20 KNHC 090337
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED MAR 09 2011

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0330 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 03N78W 
TO 05N94W TO 02N104W TO 05N114W TO 07N140W. SCATTERED MODERATE 
CONVECTION FROM 03N TO 06N BETWEEN 91W AND 98W.

...DISCUSSION...

AN AMPLIFIED UPPER PATTERN PERSISTS N OF 25N AS A VIGOROUS SHORT 
WAVE TROUGH DIGS INTO THE CENTRAL PLAINS AHEAD OF A RIDGE 
BUILDING ALONG 127W. AN ASSOCIATED 1027 MB SURFACE HIGH IS 
CENTERED NEAR 33N128W. EARLIER SHIP OBSERVATIONS AND 
SCATTEROMETER DATA SHOWED FRESH NW TO N FLOW OFF THE N AND 
CENTRAL COASTS OF BAJA CALIFORNIA AND THROUGH THE GULF OF 
CALIFORNIA BETWEEN THE SURFACE HIGH AND A LOW OVER NORTHERN 
MEXICO AND TEXAS. SCATTEROMETER DATA ALSO SHOWED FRESH NE TO E 
TRADE WIND FLOW S OF THE HIGH PRES. FURTHER W...A BROAD UPPER 
TROUGH OVER THE N CENTRAL PACIFIC N OF HAWAII IS MOVING EASTWARD 
THROUGH 155W. A PAIR OF SHORT WAVE UPPER TROUGHS SHOW UP IN 
WATER VAPOR IMAGERY FROM 27N130W TO SE OF HAWAII...AND ALONG 
125W S OF 20N. THESE UPPER TROUGHS ARE SUPPORTING WEAK SURFACE 
TROUGHS ALONG THE ITCZ...NEAR 133W AND 114W. SCATTEROMETER DATA 
ALSO SHOW AREAS OF 20 KT TRADES BETWEEN THE TROUGH NEAR 133W AND 
THE SURFACE HIGH PRES TO THE NORTH. INSTABILITY ASSOCIATED WITH 
THE UPPER TROUGH ALONG 125W IS ENHANCING SCATTERED SHOWERS NEAR 
THE SURFACE TROUGH ALONG 114W. 

LOOKING AHEAD THROUGH THU...A SERIES OF UPPER SHORT WAVE TROUGHS 
OVER THE N CENTRAL PACIFIC WILL SWING THROUGH THE NE 
PACIFIC...ERODING THE UPPER RIDGE AND ALLOWING THE WEAK UPPER 
SHORT WAVES FURTHER S TO DAMPEN OUT...CUTTING UPPER SUPPORT FROM 
THE WEAK SURFACE TROUGHS AND CONVECTION ALONG THE ITCZ. AN 
ATTENDANT WEAK COLD FRONT WILL MOVE EASTWARD TO THE NORTH OF 
HAWAII WILL MAKE SLOW PROGRESS THROUGH THE NW CORNER OF THE 
DISCUSSION AREA THROUGH LATE THU. THIS WILL ALSO PUSH THE 
SURFACE RIDGE FURTHER SOUTH...WITH THE TRADE WIND BELT SHIFTING 
S ACCORDINGLY AND BEING CONTAINED FROM 07N TO 20N W OF 120W. 
WINDS OFF THE BAJA COAST AND GULF OF CALIFORNIA ALSO DIMINISH 
LATE WED/EARLY THU AS THE SURFACE HIGH SHIFTS S...AND LOW PRES 
OVER NORTHERN MEXICO LIFTS TO THE NE. 

FURTHER EAST...BROAD UPPER RIDGING CENTERED OVER 03N105W WITH A 
RIDGE AXIS EXTENDING E ALONG 03N TO 80W. ASSOCIATED DIVERGENCE 
ALOFT IS ENHANCE SCATTERED SHOWERS ALONG THE ITCZ...EVEN THOUGH 
TOGA-TAO BUOYS AND UPPER SCATTEROMETER SHOW LOW LEVEL TRADE WIND 
CONVERGENCE REMAINS FAIRLY WEAK. LIGHT WINDS OVER THE GULF OF 
TEHUANTEPEC WILL YIELD TO NEAR GALE CONDITIONS BY EARLY THU 
MORNING AS A COLD FRONT PUSHES THROUGH THE SW GULF OF MEXICO. 
GALE CONDITIONS ARE EXPECTED BY THU AFTERNOON THROUGH THE GULF 
OF TEHUANTEPEC AND ADJACENT PACIFIC WATERS. 

$$
CHRISTENSEN