000
AXPZ20 KNHC 230850
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED MAR 23 2011

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0800 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 08N85W 
TO 01N105W TO 05N127W TO 05N140W. SCATTERED MODERATE CONVECTION 
LIES WITHIN 90 NM EITHER SIDE OF THE ITCZ AXIS W OF 131W.

...DISCUSSION...

BROAD TROUGHING ALOFT WILL AMPLIFY THIS MORNING AND LINGER OVER 
N WATERS THROUGH THE END OF THE FORECAST PERIOD FRI MORNING. A 
COLD FRONT ASSOCIATED WITH THIS TROUGH LIES FROM 32N125W TO 
25N140W. THE ASCAT PASS FROM 0542 UTC SHOWS WINDS TO 20 KT LIE W 
OF THE FRONT AS WELL AS WITHIN 210 NM E OF THE FRONT N OF 28N. 
THIS FRONT WILL WEAKEN TODAY AS IT MOVES SOUTHEASTWARD AND 
DISSIPATE OVERNIGHT TONIGHT NEAR THE NORTHERN GULF OF 
CALIFORNIA. THE NEXT BATCH OF UPPER ENERGY TO REINFORCE THE 
BROAD TROUGH ALOFT WILL MOSTLY PASS N OF THE AREA...BUT THE 
SOUTHERN END OF ITS ASSOCIATED COLD FRONT WILL CLIP THE NORTHERN 
WATERS BY THE END OF THE PERIOD.

FRESH TRADE WINDS CURRENTLY LIE FROM 06N TO 21N W OF 130W AND 
FROM 10N TO 20N BETWEEN 120W AND 130W ACCORDING TO THAT 0542 UTC 
ASCAT PASS ALONG WITH THE 0320 UTC WINDSAT PASS. THIS AREA OF 
TRADES WILL SHIFT NORTHWESTWARD OVER THE NEXT 24 HOURS AS THE 
1021 MB HIGH PRES SYSTEM NEAR 27N126W DISSIPATES AND THE HIGH 
PRES SYSTEM NORTHWEST OF THE COLD FRONT CURRENTLY STRETCHED 
ACROSS N WATERS BECOMES THE DOMINANT HIGH CENTER. THE RIDGE 
EXTENDING EASTWARD FROM THIS SECOND HIGH CENTER WILL BE FORCED 
SOUTHWARD BY THE NEXT COLD FRONT EXPECTED TO APPROACH N WATERS 
AT THE END OF THE PERIOD...CAUSING THE TRADE WINDS TO AGAIN 
SHRINK SOUTHWARD BY EARLY FRI.

A STRENGTHENING PRES GRADIENT BETWEEN THE RIDGING OVER N WATERS 
AND TROUGHING OVER CENTRAL MEXICO IS CURRENTLY PRODUCING FRESH 
NW WINDS IN THE SOUTHERN GULF OF CALIFORNIA AS WELL AS ALONG THE 
W COAST OF BAJA CALIFORNIA N OF 28N. WINDS ALONG THE WESTERN 
BAJA PENINSULA WILL EXPAND SOUTHWARD AS THE COLD FRONT TO THE W 
DISSIPATES AND RIDGING IS ALLOWED TO BUILD OVER NE WATERS.

THE MOST SIGNIFICANT AREA OF DEEP CONVECTION OVER THE FORECAST 
REGION IS ALONG THE WESTERN EDGE OF THE ITCZ. THIS AREA OF 
CONVECTION IS DESCRIBED IN THE ITCZ SECTION. THE CONVECTION HERE 
IS BEING ENHANCED BY BROAD DIFFLUENCE ALOFT. PRECIPITABLE 
WATER IMAGERY SHOW THE HIGHEST AMOUNT OF AVAILABLE MOISTURE 
POOLED ALONG THE ITCZ JUST NE OF THE GALAPAGOS ISLANDS. THIS 
AREA IS MARKED BY SUBSIDENCE AND WESTERLY SHEAR ALOFT WHICH IS 
INHIBITING CONVECTION. 

GAP WINDS...
GULF OF CALIFORNIA...A STRONG PRES GRADIENT BETWEEN TROUGHING 
OVER CENTRAL MEXICO AND RIDGING OVER N WATERS WILL ALLOW 20 KT 
WINDS TO CONTINUE OVER THE SOUTHERN PORTION OF THE GULF OF 
CALIFORNIA TODAY...MIGRATE S TOWARD CABO CORRIENTES THU AND 
REMAIN THERE THROUGH FRI MORNING.

GULFS OF PAPAGAYO AND PANAMA...WINDS ARE EXPECTED TO REMAIN ABOVE
20 KT THROUGH THU AS THE PRES GRADIENT REMAINS STRONG BETWEEN 
HIGH PRES TO THE N OVER CENTRAL AMERICA AND LOWER PRES TO THE S 
ALONG THE COAST OF COLOMBIA. THESE WINDS WILL DIMINISH BELOW 
ADVISORY CRITERIA THU AFTERNOON AS THE PRES GRADIENT SLACKENS.

$$
SCHAUER