000
AXPZ20 KNHC 040935
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI FEB 04 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 
0900 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 05N77W TO 
03N98W TO 10N111W THEN RESUMES NEAR 07N116W TO 04N140W. 
SCATTERED MODERATE TO STRONG CONVECTION IS FROM 07N TO 10N 
BETWEEN 112W AND 120W. SCATTERED MODERATE CONVECTION IS FROM 07N 
TO 09N BETWEEN 120W AND 130W.

...DISCUSSION...

E OF 110W...STRONG COLD AIR ADVECTION ASSOCIATED WITH A STRONG 
AND DEEP UPPER TROUGH THAT EXTENDS FROM THE GREAT LAKES TO THE 
SOUTHERN ROCKIES CONTINUES OVER THE GULF OF CALIFORNIA AND 
ADJACENT PACIFIC WATERS OFF THE COAST OF THE BAJA CALIFORNIA 
PENINSULA AND W OF THE CENTRAL MEXICAN COAST FROM 20N TO 23N E 
OF 110W. THESE CONDITIONS ARE RESULTING IN STRONG TO NEAR GALE 
FORCE WINDS ACROSS THE ENTIRE GULF OF CALIFORNIA. A 0514 UTC 
ASCAT PASS INDICATED 20-30 KT WINDS W OF THE BAJA CALIFORNIA 
PENINSULA. THE TROUGH WILL WEAKEN AND SHIFT E THIS WEEKEND 
ALLOWING FOR WINDS TO DIMINISH TO LESS THAN 20 KT BY SAT EVENING.

W OF 110W...A REX BLOCK PATTERN CONTINUES TO SET UP ALOFT OFF 
THE U.S. WEST COAST. A STRONG AREA OF HIGH PRES NEAR 39N131W 
WILL REMAIN IN PLACE DURING THE NEXT 48 HOURS MAINTAINING FRESH 
TO STRONG TRADE WINDS GENERALLY FROM 09N TO 28N. THESE TRADES 
COMBINED WITH THE CONDITIONS DESCRIBED ABOVE OFF THE BAJA 
CALIFORNIA COAST ARE RESULTING IN SEAS UP TO 14 FT IN FRESH NE 
SWELL WHICH IS COMMINGLING WITH LONG PERIOD NW SWELL WITH PEAK 
WAVE PERIODS OF 15 TO 16 SECONDS. WINDS AND SEAS WILL DIMINISH 
AND SUBSIDE SLIGHTLY THROUGH THE NEXT 48 HOURS AS THE PRES 
GRADIENT BEGINS TO RELAX.

GAP WINDS...
A SURGE OF DENSE COLD AIR CONTINUES TO BE FUNNELED THROUGH THE 
CHIVELA PASS FROM THE W GULF OF MEXICO DOWNWIND THROUGH THE GULF 
OF TEHUANTEPEC. THIS AIRMASS HAS BEGUN TO MODIFY WITH AN EARLIER 
WINDSAT PASS INDICATING 30 KT WINDS AND THE GALE WARNING WAS 
ALLOWED TO EXPIRE AT 00 UTC. EXPECT NORTHERLY WINDS TO PERSIST 
IN THE 20 TO 30 KT RANGE TODAY THEN WILL INCREASE TO GALE FORCE 
FOR A BRIEF 12 HOURS FRI NIGHT CONTINUING INTO EARLY SAT 
MORNING. WINDS WILL THEN QUICKLY DIMINISH TO LESS THAN 20 KT BY 
SAT NIGHT.

FURTHER SOUTHEAST...FRESH TO STRONG TRADE WINDS OVER THE 
CARIBBEAN ALONG WITH NOCTURNAL DRAINAGE EFFECTS ARE SUPPORTING 
GAP WINDS OF 20 TO 25 KT THROUGH THE GULF OF PAPAGAYO WHICH WILL 
PERSIST DURING THE NEXT 48 HOURS. FRESH NE TRADES IN THE SW 
CARIBBEAN SEA ARE PUSHING ACROSS THE ISTHMUS OF PANAMA AND INTO 
THE GULF OF PANAMA WHICH WILL CONTINUE THROUGH THE NEXT 48 HOURS.

$$
LEWITSKY