000
AXPZ20 KNHC 151002
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC THU MAR 15 2012

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 03N91W TO 
02N103W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 60 NM 
N OF THE AXIS BETWEEN 88W-92W...AND ALSO WITHIN 120 NM N OF THE 
AXIS BETWEEN 92W-99W.

...DISCUSSION...

AN UPPER LEVEL TROUGH AXIS EXTENDS FROM SRN CALIFORNIA SW INTO 
THE DISCUSSION AREA THROUGH 32N119W...TO A SMALL CYCLONIC
CIRCULATION AT 29N121W AND CONTINUES TO 25N130W TO SW OF THE 
AREA AT 21N140W. A QUITE ACTIVE JET STREAM BRANCH EXTENDS INTO
THE AREA THROUGH 18N140W...AND REACHES NEWD TO 22N125W TO 
25N119W AND TO ACROSS CENTRAL BAJA CALIFORNIA AND OVER TO NRN 
MEXICO. THIS JET CONTINUES TO ADVECT TROPICAL MOISTURE IN THE 
FORM OF BROKEN TO SCATTERED UPPER LEVEL CLOUDS NEWD TO OVER
CENTRAL AND SRN BAJA CALIFORNIA AND NRN MEXICO. POSSIBLE 
ISOLATED SHOWERS ARE WITHIN 450 NM SE OF THE JET.

THE UPPER LOW WILL QUICKLY LIFT NE AND BECOME ABSORBED INTO THE 
TROUGH ACROSS NRN BAJA CALIFORNIA LATER TODAY. THE TROUGH WILL 
SHEAR OUT NE TO SW THROUGH SAT IN RESPONSE TO A DEEPENING UPPER 
LEVEL TROUGH THAT SWINGS SEWD OVER THE NE PACIFIC AREA AND 
TOWARDS THE U.S. W COAST WHILE UPPER LEVEL RIDGING JUST W OF THE 
AREA AMPLIFIES NWD AND SHIFTS EWD. THIS WILL ALLOW FOR AN UPPER 
LEVEL IMPULSE DROPPING SWD WELL W OF THE TROUGH NEAR 20N147W TO 
PROVIDE THE IMPETUS THAT THEN DEVELOPS AN UPPER LEVEL LOW ON THE 
FAR SW PART OF THE TROUGH NEAR 11.5N139W LATE ON FRI. THIS UPPER 
LEVEL LOW WILL THEN ALSO LIFT NE AND BECOME ABSORBED BY THE 
AFOREMENTIONED TROUGH AS THE TROUGH BECOMES IN PHASE WITH THE 
SECONDARY DEEPENING UPPER TROUGH OVER THE FAR NE PORTION AND N 
OF THE AREA ON SAT. 

A WEAKENING SURFACE TROUGH ASSOCIATED WITH THE UPPER LEVEL 
TROUGH IS ANALYZED FROM 32N131W TO 28N140W AT 0600 UTC. TO ITS 
E...A STRONGER HIGH OF 1023 MB IS CENTERED AT 29N123W WITH A 
RIDGE EXTENDING SEWD TO NEAR 18N112W. HIGH PRES COVERS THE 
AREA N OF 14N W OF 109W. THE HIGH IS FORECAST TO SHIFT SW
AND STRENGTHEN DURING THE NEXT 24 HRS WITH THE TROUGH 
DISSIPATING. THE HIGH THEN BECOMES REPLACED BY STRONGER EWD 
BUILDING CENTRAL PACIFIC RIDGE THROUGH SAT. THE PRES GRADIENT 
BETWEEN THE HIGH AND LOW PRES OVER THE FAR SRN PORTION IS 
ALLOWING FOR AND AN AREA OF NE 20 KT TRADE WINDS TO EXIST FROM 
07N TO 18N W OF 114W. THESE TRADES WILL SOLIDIFY SOME W OF 130W 
WITHIN THE NEXT 36-48 HRS AS THE STRONGER RIDGE BUILDS INTO THE 
AREA. THE PRES GRADIENT BETWEEN THE 1023 MB HIGH AND LOW PRES
WITH TROUGHING OVER NW MEXICO IS PRODUCING NW 20 KT WINDS OVER
THE FAR EASTERN PORTION OF THE AREA N OF 25N WITHIN 90 NM OF
THE BAJA CALIFORNIA PENINSULA COAST. THESE WINDS WILL EXPAND W
TO WITHIN 120 NM W OF BAJA CALIFORNIA PENINSULA TONIGHT AND 
CONTINUE INTO FRI NIGHT. IN ADDITION...NW 20 KT WINDS ARE 
FORECAST TO MATERIALIZE THROUGH THE GULF OF CALIFORNIA IN ABOUT
18 HRS FROM 23N TO 26...CONTINUE WITH LITTLE CHANGE THROUGH 24 HRS
THEN DIMINISH IN 48 HRS. A STRONG COLD FRONT WILL PASS JUST TO 
THE OF THE AREA LATE ON FRI AS IT WILL BE DRIVEN BY THE 
DEEPENING UPPER TROUGH THAT MOVES TOWARDS THE U.S. W COAST AT 
THAT TIME PER NCEP MODEL CONSENSUS AS HPC SHORT RANGE FORECAST 
FOLLOWED SUITE.

THE TOTAL PRECIPITABLE WATER (TPW) IMAGERY FROM CIMSS INDICATES
THAT A LOW LEVEL TROUGH MOVING W AT ABOUT 18 KT IS ALONG 125W
S OF 1ON. SCATTERED SHOWERS AND TSTMS ARE WITHIN 120 NM ON EITHER
SIDE OF THE TROUGH FROM 04N TO 07N. A SIMILAR TROUGH...NOTED
AS RATHER ILL-DEFINED...IS ALONG 134W S OF 10N. ONLY ISOLATED 
SHOWERS ARE WITHIN 120 NM OF THE TROUGH FROM 06N-10N.

GAP WINDS... 
THE GULF OF TEHUANTEPEC...N-NE WINDS OF 20-30 KT THROUGH THE
CHIVELA PASS AND INTO THE GULF ARE FORECAST TO DIMINISH TO
20-25 KT IN 24 HRS...AND TO 20 KT BY 48 HRS AS THE PRES GRADIENT
OVER SE MEXICO SLACKENS.

THE GULF OF PAPAGAYO...FRESH TRADES ACROSS THE CARIBBEAN SEA 
CONTINUE TO FUEL NE 20 TO 25 KT GAP WINDS ACROSS CENTRAL AMERICA 
AND THROUGH THE GULF AS REVEALED BY ASCAT AND OSCAT DATA FROM 
LATE LAST NIGHT. THESE WINDS REACH DOWNSTREAM FROM THE GULF TO 
AS FAR W AS 107W WITH SEAS TO 9 FT. LITTLE CHANGE IS EXPECTED 
WITH THESE WINDS DURING THE NEXT 48 HRS.

THE GULF OF PANAMA...TRADES IN THE SW CARIBBEAN SEA WILL 
CONTINUE TO SUPPORT PULSES OF 20 KT N WINDS ACROSS THE ISTHMUS 
OF PANAMA INTO THE GULF OF PANAMA ANS S TO 05N. THE ASCAT PASS 
FROM JUST PAST 0200 UTC LAST NIGHT INDICATED SOME OF THESE 
WINDS. SEAS IN THE GULF ARE EXPECTED TO REMAIN LESS THAN 8 FT. 
THESE WINDS ARE FORECAST TO DIMINISH SHORTLY AFTER FRI NIGHT.

$$
AGUIRRE