000
AXPZ20 KNHC 120309
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
0405 UTC WED FEB 12 2014

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0215 UTC.                              
  
...SPECIAL FEATURES...

GULF OF TEHUANTEPEC...A COLD FRONT OVER THE NW GULF OF MEXICO IS 
SPREADING HIGH PRESSURE SOUTHWARD IN ITS WAKE ALONG THE EASTERN 
SLOPES OF THE SIERRA MADRE ORIENTAL MOUNTAINS. THE FRONT WILL 
MOVE THROUGH CHIVELA PASS BY WED EVENING...SENDING NORTHERLY 
WINDS INTO THE GULF OF TEHUANTEPEC. WINDS WILL INCREASE TO GALE 
FORCE OVERNIGHT WED NIGHT. THE GALE WILL BE SHORT LIVED...WITH 
CONDITIONS EXPECTED TO DIMINISH TO 30 KT BY THU AFTERNOON AS THE 
COLD FRONT RACES EASTWARD OVER THE GULF OF MEXICO AND THE 
PRESSURE GRADIENT THROUGH CHIVELA PASS WEAKENS. THE GALE FORCE 
WINDS ARE EXPECTED TO PEAK AT 35 KT WITH SEAS TO 12 FT WED NIGHT 
INTO THU.
    

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

THE MONSOON TROUGH AXIS WAS ANALYZED FROM 04N77W TO 07N90W. THE 
ITCZ AXIS WAS ANALYZED FROM 07N90W TO 05N135W TO 06N140W. 
SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS NOTED 
WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 83W AND 89W. 
SCATTERED MODERATE CONVECTION WAS FOUND WITHIN 360 NM N AND 90 
NM S OF THE AXIS BETWEEN 118W AND 133W.
 

...DISCUSSION...

SOUTHWEST FLOW ON THE S SIDE OF AN UPPER LOW NEAR 17N130W IS 
TAPPING INTO DEEP LAYERED TROPICAL MOISTURE POOLED ALONG THE 
ITCZ W OF 120W AS SEEN IN PRECIPITABLE WATER IMAGERY. SCATTERED 
MODERATE CONVECTION IS NOTED WITHIN 360 NM N AND 90 NM S OF THE 
ITCZ AXIS BETWEEN 118W AND 133W. THIS CONVECTION IS BEING 
ENHANCED BY UPPER DIFFLUENCE ASSOCIATED WITH THE REAR RIGHT 
QUADRANT OF THE SOUTHWESTERLY UPPER JET. THE LOW IS FORECAST TO 
REMAIN QUASI-STATIONARY AS THE UPPER JET STRENGTHENS AND TURNS 
MORE SOUTHERLY. PRECIPITATION SHOULD CONTINUE NEAR THIS PORTION 
OF THE ITCZ OVER THE NEXT TWO DAYS AS A RESULT.

BROAD UPPER DIFFLUENCE IS ALSO ENHANCING THE SCATTERED MODERATE 
WITH ISOLATED STRONG CONVECTION NOTED WITHIN 120 NM EITHER SIDE 
OF THE MONSOON TROUGH AXIS BETWEEN 83W AND 89W. DIFFLUENCE HERE 
IS ATTRIBUTABLE TO AN UPPER RIDGE AXIS THAT SPANS FROM AN 
ANTICYCLONE OVER WESTERN COLOMBIA TO THE GALAPAGOS ISLANDS. THE 
RIDGE AXIS IS EXPECTED TO SHIFT NORTHWARD TO 07N OVER THE NEXT 
FEW DAYS. THIS SHOULD ALLOW THE BEST CHANCE OF PRECIPITATION TO 
SHIFT NORTHWARD AND CLOSER TO THE COAST.

THE 1024 MB SUBTROPICAL HIGH NEAR 32N129W EXTENDS A RIDGE AXIS 
INTO THE FORECAST AREA TO NEAR 17N110W. THE ASCAT-A PASS FROM 
1900 UTC SHOWS FRESH TO STRONG TRADE WINDS LIE OVER W 
WATERS...GENERALLY SPANNING THE AREA FROM 06N TO 23N W OF 123W. 
THE SOUTHEAST CORNER OF THIS AREA LIES WITHIN THE REGION OF 
CONVECTION NOTED NEAR THE ITCZ. A STRONG PRESSURE GRADIENT IS 
FOUND HERE BETWEEN THE SUBTROPICAL RIDGE AND ENHANCED LOW-LEVEL 
TROUGHING ALONG THE ITCZ ATTRIBUTABLE TO THE AFOREMENTIONED 
UPPER LOW. THE SUBTROPICAL HIGH HAS WEAKENED 4 MB IN THE LAST 6 
HOURS...AND WINDS ARE IN THE PROCESS OF DIMINISHING BELOW A 
STRONG BREEZE. THE HIGH IS FORECAST TO REMAIN QUASI-STATIONARY 
AS IT IS ENCROACHED UPON BY A COLD FRONT CURRENTLY FOUND TO ITS 
NW. THIS FRONT IS NOT EXPECTED TO MAKE IT INTO THE FORECAST 
AREA. 

GULF OF PAPAGAYO...FRESH TO STRONG NE WINDS THAT HAD PULSED IN 
THE MORNING HOURS THROUGH THE GULF OF PAPAGAYO WILL TAKE A BREAK 
OVER THE NEXT FEW DAYS AS THE PRESSURE GRADIENT RELAXES IN 
ADVANCE OF THE COLD FRONT EXPECTED TO BRING GALE FORCE WINDS TO 
THE GULF OF TEHUANTEPEC. WINDS ARE EXPECTED TO ONCE AGAIN BECOME 
A STRONG BREEZE IN THE EARLY MORNING HOURS FRI...JUST AFTER THE 
OFFICIAL FORECAST PERIOD...AS THE COLD FRONT STRETCHES SOUTHWARD 
THROUGH CENTRAL AMERICA.
 
$$
SCHAUER