000
AXPZ20 KNHC 270905
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN FEB 27 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 
0700 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 06N77W 
TO 06N85W TO 02N94W THEN CONTINUES FROM 07N112W TO 04N127W TO 
05N140W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS 
WITHIN 90 NM N OF THE ITCZ AXIS E OF 79W.


...DISCUSSION...

A STRONG UPPER LEVEL CYCLONIC VORTEX IS CENTERED N OF THE AREA 
NEAR LAS VEGAS NEVADA WITH AN UPPER TROUGH REACHING FROM THIS 
VORTEX TO 25N119W. AN UPPER JET AXIS WITH CORE WIND SPEEDS OF 
120 TO 140 KT EXISTS WITHIN 600 NM E OF THE TROUGH. THE JET 
EXTENDS SOUTH AND WEST OF THE TROUGH AXIS INTO THE SE CORNER OF 
THE FORECAST AREA AND IS ADVECTING MOISTURE FROM THE DEEP 
TROPICS S OF THE BIG ISLAND OF HAWAII NORTHEASTWARD TO ACROSS 
THE BAJA CALIFORNIA PENINSULA. AN ATTENDANT SURFACE COLD FRONT 
REACHES FROM 32N113W TO 29N114W TO 24N120W TO 22N130W. THE 0540Z 
ASCAT PASS CAPTURED 20 TO 25 KT NORTHERLY WINDS W OF THE FRONT 
TO 130W. WINDS WILL DIMINISH TO LESS THAN 20 KT LATER TODAY AS 
THIS SOUTHEASTWARD MOVING FRONT DISSIPATES. NW SWELL ASSOCIATED 
WITH THE FRONT HAS PEAKED NEAR 15 FEET AND WILL GRADUALLY DECAY 
DURING THE NEXT 48 HOURS.

BROAD SURFACE RIDGING CAN BE FOUND S OF THE COLD FRONT TO 10N. 
THE PRES GRADIENT BETWEEN THIS RIDGING AND LOWER PRES ASSOCIATED 
WITH THE ITCZ IS PRODUCING AN AREA OF FRESH TRADE WINDS FROM 06N 
TO 18N W OF 125W. THESE TRADES WILL MIGRATE E OVER THE NEXT 48 
HOURS AS HIGH PRES BEHIND THE AFOREMENTIONED COLD FRONT IS 
FORCED EASTWARD BY ANOTHER COLD FRONT. THIS NEW COLD FRONT WILL 
APPROACH THE FAR NW PART OF THE FORECAST AREA BY THE END OF THE 
PERIOD...BUT THE PRES GRADIENT BETWEEN IT AND HIGH PRES TO ITS E 
WILL INCREASE SOUTHERLY WINDS TO 20 KT OVER NW WATERS BY MON 
MORNING AND WILL SLOWLY EXPAND AND INCREASE TO 25 KT BY THE END 
OF THE FORECAST PERIOD TUE MORNING.

BROAD DIFFLUENT FLOW ALOFT BETWEEN AN ANTICYCLONE OVER SOUTHERN 
MEXICO AND A WEAKENING UPPER LOW S OF THE EQUATOR NEAR 18S93W IS 
ENHANCING VERTICAL MOTION OVER THE FORECAST AREA NEAR THE COAST 
OF COLOMBIA AND ECUADOR. THIS VERTICAL LIFT HAS HELPED INDUCE 
CONVECTION ALONG THE FAR EASTERN EDGE OF THE ITCZ NEAR THE COAST 
AS DESCRIBED IN THE ITCZ SECTION ABOVE IN ADDITION TO THE 
SCATTERED MODERATE CONVECTION FOUND WITHIN 120 NM OF THE COAST 
FROM 01N TO 02N. THE ITCZ CONTINUES TO BE DISRUPTED BY THE DEEP 
LAYER TROUGHING S OF THE EQUATOR ASSOCIATED WITH THE WEAKENING 
UPPER LOW. A NEW UPPER LOW OVER SOUTH AMERICA WILL MIGRATE W ON 
MONDAY AND REINFORCE THE TROUGHING OVER THE SOUTH EASTERN 
PACIFIC...ALLOWING THE ITCZ TO REMAIN BROKEN OVER FORECAST 
WATERS.

GULF OF CALIFORNIA...THE COLD FRONT CURRENTLY OVER N WATERS HAS 
PUSHED INTO THE NORTHERN GULF AND INCREASED S TO SW WINDS TO 30 
KT N OF 29N. SOUTHERLY WINDS WILL DIMINISH TO LESS THAN 20 KT 
THIS AFTERNOON. NORTHERLY WINDS WILL INCREASE TO 20 KT IN THE 
SOUTHERN GULF OF CALIFORNIA ON MON AS A SURFACE TROUGH DEVELOPS 
OVER WESTERN MEXICO WHILE HIGH PRES RIDGING STRENGTHENS JUST W 
OF THE BAJA CALIFORNIA PENINSULA.

GULF OF PAPAGAYO...NE TO E WINDS WILL PULSE TO 20 KT IN THE 
OVERNIGHT HOURS WITH ENHANCED DRAINAGE FLOW OFF THE CENTRAL 
AMERICA LAND-MASS. THESE WINDS WILL GENERALLY PERSIST THROUGH 
TUE MORNING.

$$
SCHAUER/LEWITSKY