000
AXPZ20 KNHC 082209
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON FEB 08 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...
AXIS ANALYZED ALONG 04N77W TO 04N81W TO 07N88W TO 04N94W TO 
05N111W TO 07.5N123W TO 07N130W TO 09N135W TO 08N140W. SCATTERED 
MODERATE CONVECTION WAS OCCURRING WITHIN 120 NM N OF AXIS 
BETWEEN 118W AND 134W.

...DISCUSSION...
HIGH AMPLITUDE BLOCKING UPPER PATTERN EXTENDING FROM SRN 
HEMISPHERE ACROSS THE EQUATOR AND INTO S HALF OF AREA PAST TWO 
DAYS HAS BEGUN TO SHIFT S AND BACK INTO SRN HEMI...LEAVING BROAD 
WLYS ALOFT E OF 110W. A BROAD MIDDLE TO UPPER LEVEL TROUGH S OF 
21N BETWEEN ROUGHLY 130W AND 150W CONTINUES TO SHIFT VERY SLOWLY 
E TODAY...AND IS ALLOWING A MID LATITUDE MIDDLE TO UPPER LEVEL 
LOW NEAR 23N140W TO DIG SE INTO BACKSIDE OF BROAD LOWER LAT 
TROUGH. THESE FEATURES WILL GRADUALLY MERGE OVER THE NEXT 48 
HOURS AND DIG SE TO A POSITION FROM SRN CALIFORNIA TO 08N130W BY 
WED MORNING...WITH STRONG JET ENERGY FORECAST TO DIVE INTO 
BACKSIDE OF THIS TROUGH AND ROTATE THROUGH THE BASE AND THEN 
EXIT TO THE NE ACROSS THE N TWO-THIRDS OF MEXICO. THIS IS 
FORECAST TO INDUCE VERY ACTIVE CONVECTION ALONG THE ITCZ TO 
ABOUT 15N W OF 115W...AND ASSOCIATED LOW LEVEL REALIGNMENT OF 
THE EPAC SURFACE HIGH TO PRODUCE A VERY TIGHT PRESSURE GRADIENT 
N OF THE ITCZ LEADING TO 25-30 KT TRADES...WITH THE POTENTIAL 
FOR SMALL AREAS OF GALES. ADDITIONALLY...ABUNDANT TROPICAL 
MOISTURE WILL BE SHEARED AND TRANSPORTED ACROSS BAJA CALIFORNIA 
AND MEXICO AND COULD LEAD TO FLOOD PRODUCING RAINS LATE 
WEDNESDAY INTO THE WEEKEND...ESPECIALLY ALONG THE WRN SLOPES OF 
THE SIERRA MADRE OCCIDENTALES. 

AHEAD OF THIS EVOLVING UPPER TROUGH...A FLAT S/W UPPER RIDGE HAS 
CENTERED ALONG ABOUT 115W BETWEEN 13N AND 26N HAS PRODUCED A 
BROAD ZONE OF SWLY FLOW ALOFT TRANSPORTING HIGH CLOUDS ACROSS 
MEXICO AND INTO THE GULF OF MEXICO. CORE WIND SPEEDS AS 
ESTIMATED BY SATELLITE DERIVED WINDS WERE UP TO 120 KT. 
UNDERNEATH THIS WLY FLOW ALOFT E OF 110W WAS A MID LEVEL TUTT 
REFLECTION SNAKING FROM THE SE CARIBBEAN WWD AND INTO THE EPAC 
ALONG 90W...WHERE GENERALLY SUBSIDENCE PREVAILED N OF 10N E OF 
105W.  

ELSEWHERE AT THE SURFACE...
A TRIO OF SURFACE HIGHS ACROSS AND BEYOND THE NW PORTIONS OF THE 
AREA HAVE ALREADY INDUCED A TIGHT PRESSURE GRADIENT AND LARGE 
AREA OF FRESH NELY TRADES S OF 22-24N AND W OF 118-120W. EARLY 
AFTERNOON ASCAT PASSES VERIFIED THESE WINDS...WITH A BROAD AREA 
OF SOLID 25 KT NE WINDS DEPICTED BETWEEN THE ITCZ AND 18N W OF 
120W. THESE FRESH WINDS ARE QUICKLY BUILDING NELY WIND SWELL 
ACROSS THIS REGION THAT WILL SLOWLY SHIFT AND EXPAND E AND NE 
DURING THE NEXT 48 HOURS. OTHERWISE...SEAS ACROSS THE AREA 
WATERS ARE GENERALLY DOMINATED BY PULSE AFTER PULSE OF LONG 
PERIOD NW SWELL. MIXING OF THIS SWELL WITH THE NELY WIND SWELL 
WITHIN THE TRADES IS YIELDING SEAS UP TO 15 FT IN THIS REGION OF 
FRESH TRADES. ADDITIONALLY...LONG PERIOD S TO SW SWELL IS 
MOVING INTO W PORTIONS OF THE AREA TODAY. 

THE SURFACE HIGHS HAVE ALSO CREATED A MODEST PRESSURE GRADIENT 
ALONG THE COAST OF SRN CALIFORNIA EXTENDING S ALONG THE W COAST 
OF THE BAJA PENINSULA...PRODUCING NW WINDS AROUND 20 KT...AND 
SEAS 10 TO 12 FT IN NW SWELL.

GAP WINDS...
E WINDS NEAR 20 KT IN GULF OF PAPAGAYO SHOULD DIMINISH WITHIN 
NEXT 24 TO 30 HRS.

THE PRES GRADIENT IN SW CARIBBEAN WILL STRENGTHEN IN 48 HOURS 
ENHANCING NORTHERLY FLOW INTO GULF OF PANAMA WITH FRESH N BREEZE 
EXPECTED EARLY WED. 

A STRONG COLD FRONT WILL MOVE THROUGH THE GULF OF MEXICO AND BAY 
OF CAMPECHE LATE TUE AND TUE NIGHT WITH NORTHERLY WINDS CROSSING 
THROUGH THE CHIVELAS PASS AND THROUGH THE GULF OF TEHAUNTEPEC... 
INCREASING TO 25-30 KT LATE TUE NIGHT...POSSIBLY REACHING GALE 
FORCE BEYOND THIS FORECAST PERIOD. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
STRIPLING