000
AXPZ20 KNHC 042123
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON JUN 04 2012

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 
2100 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH IS ALONG 09N84W TO 10N95W. THE INTERTROPICAL 
CONVERGENCE ZONE AXIS EXTENDS FROM 10N100W TO 07N111W TO A 1010 
MB LOW NEAR 09N121W TO 06N126W TO 06N140W. SCATTERED MODERATE 
CONVECTION IS FROM 03N TO 05N BETWEEN 82W AND 88W...AND FROM 05N 
TO 13N BETWEEN 88W AND 93W. WIDELY SCATTERED MODERATE CONVECTION 
IS FROM 04N TO 08N BETWEEN 114W AND 118W.

...DISCUSSION...

WATER VAPOR IMAGERY INDICATES THE UPPER LEVEL PATTERN ACROSS THE 
PACIFIC IS CURRENTLY MARKED BY AN UPPER LEVEL ANTICYCLONIC 
CIRCULATION CENTERED OVER HONDURAS NEAR 15N87W...AN UPPER LEVEL 
TROUGH ALONG 104W N OF 10N...A RIDGE WITH AXIS ALONG 117W N OF 
10N...AND A CUT-OFF UPPER LEVEL LOW CENTERED JUST EAST OF THE 
HAWAIIAN ISLANDS NEAR 20N152W. THE UPPER LEVEL RIDGING OVER THE 
CENTRAL WATERS IS SLOWLY ERODING DUE TO A PROGRESSIVE NORTHERN 
STREAM UPPER LEVEL TROUGH ENCROACHING ON ITS NORTHERN PERIPHERY 
ENROUTE TOWARDS THE U.S. WEST COAST TONIGHT THROUGH EARLY 
TUESDAY. MIDDLE TO UPPER LEVEL ENERGY ASSOCIATED WITH THIS 
TROUGHING IS EXPECTED TO SLOWLY SLIP SOUTH OF 30N ON TUESDAY AND 
DISSIPATE THE RIDGING. FARTHER EAST...A 30-45 KT SOUTHWESTERLY 
UPPER LEVEL JET OVER SOUTHERN MEXICO IS SHEARING CONVECTION 
OCCURRING N OF 10N BETWEEN 94W AND 103W. THIS CONVECTION IS 
DESCRIBED IN THE MONSOON TROUGH/ITCZ SECTION ABOVE.  

AT THE SURFACE...A COLD FRONT ASSOCIATED WITH THE AFOREMENTIONED 
NORTHERN STREAM TROUGH ALOFT IS ANALYZED FROM 30N127W TO 26N140W 
IN THE NW WATERS. THIS FRONT IS USHERING FRESH N TO NE WINDS 
INTO THE FORECAST AREA ACCORDING TO A RECENT 04/1826 UTC ASCAT 
PASS. A 1029 MB SUBTROPICAL HIGH CURRENTLY RESIDES WELL NW OF 
THIS FRONT NEAR 35N146W. THE HIGH IS FORECAST TO SHIFT EAST- 
SOUTHEASTWARD BEHIND THE COLD FRONT OVER THE NEXT 24 HOURS. THE 
PRESSURE GRADIENT WILL STRENGTHEN OVER THE NORTHERN WATERS 
TUESDAY BETWEEN THE SUBTROPICAL RIDGE AND SURFACE TROUGHING OVER 
THE WESTERN CONUS AND NW MEXICO...WITH FRESH TO STRONG NW TO N 
WINDS EXPECTED OFF BAJA CALIFORNIA AND SEAS BUILDING TO 12 FT BY 
EARLY WEDNESDAY IN NW SWELL. THE PRESSURE GRADIENT WILL ALSO 
INCREASE NORTH OF THE ITCZ OVER THE WESTERN WATERS AND ALLOW 
FRESH NE TRADE WINDS TO RETURN BY TUESDAY FROM 09N TO 26N W OF 
128W.

A 1010 MB LOW IS EMBEDDED WITHIN THE ITCZ CENTERED NEAR 09N121W. 
EARLIER MORNING ASCAT PASSES SHOW 20 KT WINDS RESIDE WITHIN 150 
NM NW OF THE LOW CENTER AND EARLIER ALTIMETER DATA FROM JASON2 
AND JASON1 PASSES SHOW SEAS TO 8 FT NEAR THE LOW. THE LOW IS 
FORECAST TO CONTINUE MOVING WESTWARD AROUND 10 KT OVER THE NEXT 
FEW DAYS. AS THE SUBTROPICAL RIDGE BUILDS TO THE NORTH...THE 
AREA OF FRESH WINDS IN THE N SEMICIRCLE OF THE LOW IS EXPECTED 
TO EXPAND.

$$
HUFFMAN