000
AXPZ20 KNHC 150324
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON NOV 15 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...ITCZ...
AXIS ANALYZED ALONG 09N84W TO 06N95W TO LOW PRES 1011 MB NEAR 
11N111W TO 09N120W TO 10N130W TO 07N140W. SCATTERED MODERATE 
CONVECTION WITHIN 120 NM EITHER SIDE OF AXIS BETWEEN 128W AND 
134W.

...DISCUSSION...
UPPER LEVEL PATTERN ACROSS THE DISCUSSION AREA CHARACTERIZED BY 
OMEGA BLOCK CENTERED ON A LARGE DEEP LAYERED RIDGE OVER THE NE 
PACIFIC WITH AN EXPANSIVE UPPER ANTICYCLONE NEAR 39N136W. A 
SHEARING MID TO UPPER LEVEL TROUGH EXTENDED FROM A BROAD UPPER 
CYCLONE OVER THE NRN U.S. CUTTING SW ACROSS ERN NEW MEXICO TO A 
SHEARED UPPER LEVEL CYCLONIC CIRCULATION NEAR 28N109W THEN 
CONTINUES WSW ACROSS BAJA CALIFORNIA AND CONTINUES AS A SHEAR 
AXIS THROUGH 24N130W TO 25N140W.  

ANOTHER UPPER LEVEL ANTICYCLONE WAS CENTERED OVER NICARAGUA AND 
HONDURAS WITH AN ASSOCIATED RIDGE AXIS EXTENDING NW ALONG THE 
COAST OF MEXICO NEAR 20N115W. UPPER LEVEL FLOW WAS TURNING TO 
THE W AND SW BETWEEN THE RIDGE AND TROUGH NOTED ABOVE GENERALLY
BETWEEN 90W AND 120W. A BROAD MID TO UPPER LEVEL CYCLONE WAS 
CENTERED NEAR 05N125W WITH THE CIRCULATION SPANNING BOTH SIDES 
OF THE EQUATOR. AN UPPER LEVEL DEFORMATION ZONE TO THE NW OF 
THIS FEATURE WAS AIDING IN SUSTAINING DEEP CONVECTION IN THE 
VICINITY OF A SURFACE TROUGH ALONG 130W. DEEP CONVECTION IN THE 
VICINITY OF A SURFACE LOW NEAR 11N111W WAS DUE IN PART TO 
DIVERGENT FLOW ALOFT TO THE NE OF THE UPPER CYCLONE NOTED ABOVE.

SIGNIFICANT UPPER LEVEL SHORT WAVE ENERGY IS FORECAST BY ALL THE 
GLOBAL MODELS TO MOVE OVER THE TOP OF THE UPPER RIDGE AND BEGIN 
TO FLATTEN AND WEAKEN THIS STRONG RIDGE BY 48 TO 72 
HOURS...DEPENDING ON THE MODEL SOLUTIONS. THIS WILL BRING ABOUT 
A SIGNIFICANT PATTERN CHANGE BY THE END OF THE WEEK. 

CURRENTLY...SPRAWLING 1040 MB HIGH PRES WAS CENTERED UNDER THE 
UPPER RIDGE NEAR 41N140W WITH THE ASSOCIATED RIDGE AXIS 
EXTENDING WELL INTO THE DISCUSSION AREA TO NEAR 18N110W. THE 
STRONG PRES GRADIENT CREATED BETWEEN THIS LARGE HIGH AND LOWER 
PRESSURES ACROSS THE TROPICS WAS MAINTAINING FRESH NE TRADES OF 
20-25 KT GENERALLY N OF 11N AND W OF 125W...WITH N TO NE WINDS 
OF 30 KT INDICATED BY A 1520 UTC WINDSAT PASS ALONG 30N BETWEEN
128W AND 132W. NE WIND SWELL ACROSS THIS AREA WAS MIXING WITH 
LONG PERIOD NW SWELL TO PRODUCE SEAS OF 8 TO 12 FT...AND 13 TO 
14 FT IN THE AREA OF 30 KT WINDS. THIS SURFACE HIGH IS ALSO 
FORECAST TO WEAKEN...FLATTEN...AND SHIFT SLOWLY W DURING THE 
NEXT FEW DAYS...ALLOWING THE GRADIENT INDUCED TRADEWINDS TO 
DIMINISH CONSIDERABLY. 

A MONSOONAL CIRCULATION HAS AGAIN EVOLVED DURING THE PAST FEW 
DAYS ACROSS THE SW CARIBBEAN AND FAR TROPICAL EPAC...WITH SW 
WINDS OF 20 KT OCCURRING N OF 03N AND E OF 86W THIS MORNING. 
THIS FLOW IS EXPECTED TO PREVAIL THROUGH 24 HOURS AND THEN SHIFT 
E OF 82W BY 48 HOURS. THIS FLOW WAS FEEDING INTO AN AREA OF LOW 
PRES OVER THE SW CARIBBEAN WHICH NOW HAS A LOW POTENTIAL FOR 
TROPICAL CYCLONE FORMATION OVER THE NEXT 48 HOURS. 

$$
COBB