000
AXPZ20 KNHC 231815 CCA
TWDEP 

TROPICAL WEATHER DISCUSSION...CORRECTED                        
NWS NATIONAL HURRICANE CENTER MIAMI FL
1750 UTC MON FEB 23 2015

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 
1730 UTC. 

...SPECIAL FEATURE... 

GULF OF TEHUANTEPEC GALE WARNING...STRONG HIGH PRES RIDGING SWD 
ACROSS SOUTHEASTERN MEXICO TO JUST N OF THE GULF IS PRODUCING N 
WINDS OF 20-25 KT WITHIN ABOUT 45 NM OF A LINE FROM 16N95W TO 
15N95W. THE PRES GRADIENT WILL CONTINUE TO TIGHTEN THROUGH THIS 
EVENING ALLOWING FOR THE WINDS TO INCREASE TO 30 KT...THEN WITH 
ASSISTANCE OF THE NOCTURNAL DRAINAGE FLOW FACTOR KICKING IN 
DURING THE OVERNIGHT HOURS THIS WILL HELP THE WINDS TO INCREASE 
TO MINIMAL GALE FORCE WITH SEAS BUILDING TO AROUND 12 FT. BY 12 
UTC TUE...THE N WINDS ARE EXPECTED TO BE IN THE 30-35 KT RANGE 
WITH SEAS TO 13 FT. WINDS ARE FORECAST TO DIMINISH TO JUST BELOW 
GALE FORCE BY LATE TUE AFTERNOON OR EARLY ON TUE EVENING...AND 
TO 20 KT OR LESS BY LATE TUE NIGHT AS THE PRES GRADIENT 
SLACKENS. 
                           
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

THE ITCZ EXTENDS FROM 06N90W TO 04N103W TO 03N112W TO 05N125W TO 
LOW PRES NEAR 08N134W 1007 MB TO BEYOND 06N140W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM OF THE ITCZ 
W OF 134W...AND ALSO FROM 02N TO 05N BETWEEN 77W AND 79W.   

...DISCUSSION... 

ALOFT...A VIGOROUS AND NARROW UPPER TROUGH EXTENDS FROM 32N138W 
TO AN ELONGATED UPPER LOW NEAR 15N139W. THE TROUGH CONTINUES SE 
TO NEAR 02N122W. TO THE E OF THE TROUGH...A BROAD UPPER LEVEL 
RIDGING DOMINATES THE AREA BETWEEN 119W-137W. A SMALL 
ANTICYCLONE IS AT 04N93W WITH A RIDGE AXIS EXTENDING N TO OVER 
SE MEXICO...AND NE OVER THE YUCATAN PENINSULA. THE RIDGE ALSO 
DOMINATES MOST OF CENTRAL AMERICA. AN INVERTED TROUGH IS NOTED 
OVER FAR WESTERN COLOMBIA. A SURFACE TROUGH REFLECTION OF THE 
UPPER TROUGH IS ANALYZED FROM A 1007 MB LOW ON THE ITCZ NEAR 
08N134W NNW TO 14N135W AND TO 20N134W. SATELLITE IMAGERY SHOWS 
VERY ACTIVE WEATHER IN THE FORM OF SCATTERED MODERATE/ISOLATED 
STRONG TSTM CLUSTERS TO THE E OF THE TROUGH FROM 10N TO 19N 
BETWEEN 121W AND 129W...AND S OF THE ITCZ TO 05N BETWEEN 126W 
AND 138W. THIS LARGE AREA OF CONVECTION IS PART OF EXTENSIVE 
DEEP ATMOSPHERIC MOISTURE AHEAD OF THE UPPER TROUGH WHERE AMPLE 
DIVERGENCE IS OCCURRING. MODERATE SUBSIDENCE IS NOTED W OF THE 
UPPER TROUGH MAINTAINING A RATHER STABLE ATMOSPHERE THERE WITH 
SCATTERED TO BROKEN STRATOCUMULUS CLOUDS MOVING SSW. ASCAT DATA 
FROM LAST NIGHT REVEALED NE TO E 20-25 KT WINDS WITHIN ABOUT 180 
NM EITHER SIDE OF THE TROUGH FROM 19N TO 22N. SEAS THERE ARE IN 
THE 7-9 FT RANGE. THE SURFACE TROUGH WILL SLOWLY MOVE WESTWARD 
OVER THE NEXT COUPLE OF DAYS IN TANDEM WITH THE UPPER LOW. THE 
PRES GRADIENT BETWEEN THE TROUGH AND A BUILDING RIDGE ACROSS THE 
N WATERS WILL TIGHTEN OVER THE NEXT 48 HOURS EXPANDING THE NE TO 
E 20-25 KT WINDS ON EITHER SIDE OF THE TROUGH WITH SEAS BUILDING 
TO 9-11 FT FT.

A SURFACE RIDGE EXTENDS FROM 32N135W SE TO NEAR 23N114W. A 
DISSIPATING COLD FRONT IS OVER THE NE PORTION OF THE AREA FROM 
NORTHERN BAJA CALIFORNIA SW TO NEAR 27N128W. AS THE PREVIOUSLY  
MENTIONED TROUGH MOVES WESTWARD...THE RIDGE WILL STRENGTHEN 
ALLOWING FOR NW WINDS ALONG THE BAJA CALIFORNIA PENINSULA TO 
INCREASE TO 15-20 KT WITH SEAS IN THE 5-7 FT RANGE.
 
GAP WINDS...                 
GULF OF CALIFORNIA...A TROUGH IS JUST INLAND THE MEXICAN COAST 
FROM 30N115W TO 22N106W WHILE A 1006 MB LOW IS OVER WESTERN 
NEVADA. THE PRES GRADIENT OVER THE FAR NORTHERN PART OF THE GULF 
HAS TIGHTEN OVER THE LAST 24 HOURS...AND HAS INITIATED SW WINDS 
OF 20-25 KT N OF 30N. THESE WINDS WILL BE SHORT-LIVED OVER THE 
FAR NORTHERN PART OF THE GULF AS THEY ARE FORECAST TO DIMINISH 
TO 20 KT OR LESS BY EARLY THIS EVENING...THEN DEVELOP AGAIN 
EARLY ON TUE. BY TUE EVENING...THE WINDS WILL BE CONFINED TO N 
OF 27N...THEN SHIFT SOUTHWARD FROM 26N-29N BY LATE TUE 
NIGHT...AND FROM 24N TO 27N BY EARLY ON WED WITH SEAS TO AROUND 
THE RANGE OF 6-7 FT.
 
GULF OF PAPAGAYO...NE WINDS OF 20-25 KT ARE OCCURRING THROUGH 
THE GULF AND WESTWARD TO NEAR 89W AS A TIGHT PRES GRADEINT FROM 
STRONG RIDGING OVER CENTRAL AMERICA CONTINUES IN PLAY. THESE 
WINDS ARE FORECAST TO DIMINISH TO 20 KT OR LESS BY EARLY THIS 
EVENING...THEN PULSE AGAIN TO 20-25 KT DURING THE OVERNIGHT 
HOURS AND INTO EARLY TUE MORNING WITH THE AID OF THE NOCTURNAL 
DRAINAGE FLOW. THESE WINDS WILL THEN DIMINISH TUE AFTERNOON. 

GULF OF PANAMA...N WINDS OF 20-25 KT THROUGH THE GULF OF PANAMA 
ARE FORECAST TO WEAKEN THIS AFTERNOON...THEN START UP AGAIN LATE 
TONIGHT INTO EARLY TUE BEFORE DIMINISHING ONCE AGAIN. THE SHORT 
OF THESE WINDS SHOULD ALLOW FOR SEAS THERE TO BRIEFLY BUILD TO 8 
FT EARLY TUE BEFORE SUBSIDING TO 5-6 FT TUE EVENING.

$$ 
AGUIRRE