000
AXPZ20 KNHC 272201
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC MON MAY 27 2013

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...SPECIAL FEATURE...

A 1008 MB LOW PRES EMBEDDED WITHIN THE MONSOON TROUGH IS LOCATED 
NEAR 14N96W...OR ABOUT 200 NM SSW OF THE GULF OF TEHUANTEPEC 
MOVING SLOWLY NW. THIS SYSTEM IS GRADUALLY BECOMING BETTER 
ORGANIZED AS OBSERVED ON SATELLITE IMAGERY FROM THROUGHOUT THE 
DAY. THE CYCLONIC IS READILY MORE NOTICEABLE ON VISIBLE 
IMAGERY. CONVECTION EXISTS IN CLUSTERS OF SCATTERED 
MODERATE/ISOLATED STRONG TYPE INTENSITY NOT AROUND THE IMMEDIATE 
CENTER...BUT FROM 12N TO 15N BETWEEN 94W AND 97W. THERE IS A 
HIGH PROBABILITY OF TROPICAL CYCLONE FORMATION WITH THIS SYSTEM 
DURING THE NEXT 48 HOURS AS IT MOVES IN NORTHWARD DIRECTION 
TOWARDS THE COAST OF SOUTHERN MEXICO. REGARDLESS OF 
DEVELOPMENT...HEAVY RAINS ARE LIKELY OVER PORTIONS OF SOUTHERN 
MEXICO AND WESTERN CENTRAL AMERICA THROUGH THE NEXT 48 HOURS DUE 
TO THE PERSISTENTLY STRONG ONSHORE FLOW MEETING THE ELEVATED 
TERRAIN. THESE RAINS COULD PRODUCE LIFE-THREATENING FLASH FLOODS 
AND MUD SLIDES. SEE LATEST TROPICAL WEATHER OUTLOOK FOR LATEST 
TROPICAL CYCLONE POTENTIAL ON THIS SYSTEM.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
MONSOON TROUGH AXIS EXTENDS FROM 09N79W TO 10N89W TO LOW PRES 
NEAR 14N96W 1007 MB TO 14N105W TO LOW PRES NEAR 11N114W 1009 MB 
TO 10N127W TO 08N137W THEN ITCZ AXIS TO 08N140W. SCATTERED 
STRONG CONVECTION IS WITHIN 90 NM OF AXIS BETWEEN 91W-94W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM N 
AND 60 NM S OF THE AXIS BETWEEN 97W-101W. SCATTERED MODERATE 
WITHIN CONVECTION IS 120 NM S OF AXIS BETWEEN 120W-124W...WITHIN 
75 NM N OF AXIS BETWEEN 124W-127W AND WITHIN 120 NM S OF AXIS 
BETWEEN 132W-136W. 

NUMEROUS MODERATE TO STRONG CONVECTION IS S OF AXIS WITHIN 90 NM 
OF LINE FROM 06N81W TO 07N85W TO 07N89W.

SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS S OF THE 
MONSOON TROUGH WITHIN 60 NM OF LINE 10N96W TO 10N99W.

...DISCUSSION...

ALOFT...AN UPPER TROUGH EXTENDS ACROSS THE NW PART OF THE AREA 
FROM SRN CALIFORNIA THROUGH 32N120W AND CONTINUES SW TO 28N134W 
WHERE IT BECOMES A SHEAR AXIS TO AN UPPER LOW W OF THE AREA AT 
19N148W. SWLY LOW AHEAD OF THE TROUGH CONTINUES TO ADVECT DEEP 
TROPICAL MOISTURE FROM THE CENTRAL PACIFIC NEWD TO ACROSS THE 
FAR WRN PORTIONS...THEN THINS OUT AS IT SPREADS NEWD ACROSS NRN 
BAJA CALIFORNIA AND ACROSS THE SW CONUS. TO THE SE OF THE 
TROUGH...BROAD ANTICYCLONIC FLOW COVERS THE AREA E TO INLAND 
CENTRAL MEXICO WITH ASSOCIATED PAIR OF ANTICYCLONES...ONE NEAR 
15N122W AND THE OTHER NEAR 19N109W. AN UPPER LEVEL TROUGH HAS 
JUST MOVED E OF MEXICO TO THE FAR WRN GULF OF MEXICO...WITH ITS 
BASE STRETCHING SWWD TO NEAR 15N97W. OVER THE ERN PORTION 
...ANOTHER ANTICYCLONE CENTERED JUST SW OF GUATEMALA COVERS SE 
MEXICO...NORTHERN CENTRAL AMERICA...AND THE AREA JUST NE OF THE 
SPECIAL FEATURE LOW. UPPER DIFFLUENCE ASSOCIATED WITH THIS RIDGE 
IS HELPING TO SUSTAIN INCREASING CLUSTERS OF MODERATE TO STRONG 
CONVECTION OVER PARTS OF SE MEXICO...NORTHERN CENTRAL AMERICA 
AND IN THE VICINITY OF THE SPECIAL FEATURE LOW.

FARTHER WEST...A 1009 MB LOW PRES IS ALSO EMBEDDED WITHIN THE 
MONSOON TROUGH NEAR 11N113W. SCATTERED STRONG CONVECTION IS 
WITHIN 150 NM OF THE LOW IN THE W QUADRANTS. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 150 NM OF THE LOW 
IN THE SW QUADRANT. THIS LOW HAS A LOW CHANCE OF DEVELOPING INTO 
A TROPICAL CYCLONE OVER THE NEXT 48 HOURS AS IT IS FORECAST TO 
REMAIN WEAK.
 
ELSEWHERE AT THE SURFACE...A 1030 MB HIGH PRES LOCATED NEAR 
32N139W EXTENDS A RIDGE SEWD ACROSS THE FORECAST WATERS TO 
26N122W AND TO NEAR 20N115W. ASCAT DATA FROM EARLIER TODAY 
CONFIRMED THAT FRESH TO STRONG TRADES EXISTS BETWEEN THE SRN 
PERIPHERY OF THE RIDGE AND THE ITCZ...COVERING THE AREA FROM 10N 
TO 20N W OF 124W. DUE TO A TIGHT PRES GRADIENT BETWEEN THE RIDGE 
AND LOWER PRES OVER NW MEXICO...WINDS HAVE INCREASED OVER THE NE 
PART OF THE FORECAST REGION N OF ABOUT 29N AND E OF 120W WITH 
SEAS TO 9 FT. EXPECT THESE WIND CONDITIONS TO PERSIST OVER THE 
NEXT 48 HOURS WITH SEAS BUILDING TO 10 FT.
 
LONG PERIOD CROSS EQUATORIAL SW SWELLS AT 14-16 SECONDS DOMINATE 
MOST OF THE FORECAST WATERS E OF 115W. THESE SWELLS ARE MERGING 
WITH NW SWELLS THAT COVER THE REMAINDER OF THE FORECAST WATERS. 
WAVEWATCH GUIDANCE SUGGESTS THAT THESE SWELLS WILL SLOWLY 
SUBSIDE ON TUE...EXCEPT FOR THE NE PORTION OF THE AREA WHERE A 
NEW SET OF NW SWELLS IS FORECAST TO IMPACT THAT REGION.  
 
$$ 
AGUIRRE