000
AXPZ20 KNHC 082146
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE MAR 08 2011

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2130 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 05N84W 
TO 06N88W TO 02N102W TO 05N113W TO 04N120W TO 06N140W. SCATTERED 
MODERATE CONVECTION FROM 03N TO 05N BETWEEN 90W AND 95W. 
SCATTERED MODERATE CONVECTION WITHIN 120 NM N OF AXIS BETWEEN 
112W AND 117W.

...DISCUSSION...

AN AMPLIFIED UPPER PATTERN PERSISTS N OF 25N AS A VIGOROUS SHORT 
WAVE TROUGH DIGS THROUGH ROCKIES INTO THE CENTRAL PLAINS AHEAD 
OF A RIDGE BUILDING ALONG 130W. AN ASSOCIATED 1028 MB SURFACE 
HIGH IS CENTERED NEAR 32N131W. SHIP OBSERVATIONS AND 
SCATTEROMETER DATA SHOW 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 TROUGH OVER NORTHERN MEXICO. 
SCATTEROMETER DATA ALSO SHOW 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. SHIP AND SCATTEROMETER DATA 
ALSO SHOW FRESH GAP FLOW THROUGH PAPAGAYO. THIS FLOW WILL 
DIMINISH BY MIDDAY WED. GLOBAL MODELS DO NOT SHOW ANY FURTHER 
PAPAGAYO PULSES UNTIL THU NIGHT/EARLY FRI MORNING. 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 POSSIBLE BY THU AFTERNOON THROUGH 
THE GULF OF TEHUANTEPEC AND ADJACENT PACIFIC WATERS. 

$$
CHRISTENSEN