000
AXPZ20 KNHC 271616
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED OCT 27 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...

AXIS CENTERED ALONG 9N85W TO 1009 MB LOW NEAR 10N93W TO 9N100W
TO 11N110W TO 1009 MB LOW NEAR 11N119W TO 8N130W TO 8N140W.
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 30 NM 
OF THE AXIS E OF 88W...BETWEEN 121W-123W AND WITHIN 120 NM N OF
THE AXIS BETWEEN 105W-108W.

...DISCUSSION...

THE UPPER PATTERNS REMAINS SOMEWHAT COMPLEX AS TWO UPPER LEVEL
CYCLONIC CIRCULATIONS NOTED NEAR 6N126W...AND OVER THE NW 
PORTION OF THE AREA MOVING NE NEAR 22N137W ARE CONNECTED BY A
SHARPENING TROUGH AXIS FROM THE NORTHERN MOST CIRCULATION TO
THE ONE NEAR 6N126W. A RATHER VIGOROUS DEEPENING UPPER TROUGH
IS PRESSING TOWARDS THE FAR NW CORNER OF THE AREA. THE TROUGH
WILL SWING SE AND E ACROSS THE FAR NORTHERN PORTION THU INTO
FRI NIGHT AS A STRONG UPPER LOW WELL N OF THE REGION NEAR
44N137W DIVES SEWD TO NEAR 25N126W BY FRI NIGHT...THEN TRACKS
EWD ACROSS THE WESTERN U.S. SAT. UPPER LEVEL MOISTURE IN THE FORM
OF SCATTERED TO BROKEN HIGH CLOUDS IS STREAMING NEWD INTO THE
NW AN N PORTION S OF THE AREA AHEAD OF THE UPPER TROUGH. SIMILAR
MOISTURE IS NOTED BETWEEN THE TWO UPPER LEVEL CYCLONIC 
CIRCULATIONS FROM 11N TO 15N W OF 133W...AND FROM 13N TO 25N 
BETWEEN 130W-134W.

OVER THE EASTERN PORTION OF THE AREA...BROAD ANTICYCLONIC ALOFT 
COVERS THE AREA N OF 10N BETWEEN 112W AND 131W WITH A SMALL 
ANTICYCLONE LOCATED NEAR 15N113W. SLIGHT CONFLUENT FLOW TO THE 
SE OF THE UPPER TROUGH IS HELPING TO SUSTAIN SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION TO NE OF A 1009 MB LOW NEAR 
11N119W FROM 12N TO 14N BETWEEN 117W AND 120W...AND ALSO 
SCATTERED MODERATE CONVECTION WITHIN 120 NM SW OF THE LOW. AN 
UPPER LEVEL ANTICYCLONE CENTERED E OF THE AREA JUST TO THE E OF 
BELIZE EXTENDS A RIDGE WESTWARD TO ACROSS SOUTHEASTERN MEXICO
AND TO NEAR 16N109W. TO THE S OF THE RIDGE...ITCZ CONVECTION
IS ACTIVE E OF ABOUT 92W. MODERATE UPPER LEVEL EASTERLY WINDS 
ARE NOTED IN SATELLITE-DERIVED DATA S OF THE RIDGE TO 2N AND 
E OF 95W. WATER VAPOR IMAGERY SHOWS ABUNDANT MODERATE SUBSIDING 
AND RESULTING DRY STABLE AIR TO S OF 30N AND E OF THE UPPER 
TROUGH...EXCEPT NEAR AND ALONG THE ITCZ WITH CONVECTION 
DESCRIBED ABOVE.

AT THE SURFACE...A STRONG PACIFIC COLD FRONT ASSOCIATED WITH THE 
DEEPENING UPPER TROUGH EXTENDS FROM 32N136W TO JUST W OF THE 
AREA NEAR 30N145W. THE FRONT WILL MOVE TO ALONG 32N131W TO 
27N136W TO 26N140W IN ABOUT 24 HOURS WITH NW TO N WINDS OF 20 KT 
BEHIND IT N OF 27N...AND FOLLOWED WITH A NEW TRAIN OF LARGE LONG 
PERIOD NW SWELLS...POSSIBLY REACHING UP TO 15 FT PER LATEST 
WAVEWATCH MODEL GUIDANCE IN 48 HOURS BEHIND IT N OF 26N. N OF 
29N WITHIN 120 NM E OF FRONT SW WINDS OF 20 KT WITH SEAS 8 TO 12 
FT IN NW SWELL BY 48 HOURS.

A COUPLE OF WEAK LOWS...ONE NEAR 10N92W 1009 MB AND THE OTHER ONE
NEAR 11N119W 1009 MB DO NOT SEEM THAT THEY WILL DEVELOP INTO 
TROPICAL ENTITIES OVER THE NEXT 48 HOURS DUE TO THE INHIBITING 
FACTORS OF DRY AIR ALOFT AS MENTIONED ABOVE...COOL SSTS AND 
SHEAR FROM OF UPPER LEVEL WESTERLIES. THE EASTERN ONE MOST LOW 
HELP TO FORCE FRESH SW MONSOONAL FLOW AGAINST COAST OF 
COLOMBIA...PANAMA AND COSTA RICA...BUT FLOW BECOMES MODERATE AS 
LOW PRES WEAKENS AND DRIFTS NW. THE LOW NEAR 11N119W IS FORECAST 
TO MOVE WNW NEAR 7 KT OVER THE NEXT 48 HOURS WITH WINDS OF 20 KT 
WITHIN 60-90 NM OF ITS CENTER...MAINLY IN THE SE AND NW BY 48 
HOURS.

GAP WINDS...
THE ONSET OF THE NEXT GALE EVENT THROUGH THE GULF OF TEHUANTEPEC
IS FORECAST TO BEGIN THU NIGHT AS HIGH PRES SURGES SE ACROSS THE 
INTERIOR OF MEXICO IN THE WAKE OF A GULF OF MEXICO COLD FRONT. 
GALE N WINDS OF 25 TO 35 KT SHOULD BEGIN WITHIN 90 NM FROM THE 
GULF COAST...EXPANDING TO WITHIN 30 NM OF A LINE FROM 16N95W TO 
14N96W BY 48 HOURS WITH SEAS BUILDING UP TO 13 FT.

$$
AGUIRRE