000
ATPQ40 PGUM 120246
SIMGUM

SATELLITE INTERPRETATION MESSAGE
NATIONAL WEATHER SERVICE TIYAN GU
100 PM CHST TUE MAR 12 2013

WESTERN NORTH PACIFIC BETWEEN EQUATOR AND 25N FROM 130E TO 180.

A SHEAR LINE STRETCHES SOUTHWESTWARD ACROSS THE MARIANA ISLANDS FROM 
18N150E TO JUST WEST OF YAP NEAR 10N137E. SOME LOW-LEVEL CLOUDS AND 
PATCHY SHOWERS ARE FOUND ALONG THE SHEAR LINE AND ESPECIALLY WITHIN 
A 100 MILE WIDE BAND IN THE VICINITY OF THE MARIANAS. 

TWO OTHER WEAK SHEAR LINES ARE IN THE REGION...ONE TO THE NORTHEAST 
OF LUZON FROM 22N136E TO WEST OF 22N130E AND THE SECOND IN THE 
VICINITY OF WAKE ISLAND FROM 14N180 TO 13N170E AND ENDING NEAR 
20N164E. BOTH OF THESE CONTAIN PATCHY LOW-LEVEL CLOUDS AND ISOLATED
SHOWERS WITHIN A 100 MILE WIND BAND.

FARTHER SOUTH...THE EQUATORIAL TROUGH REMAINS ALONG 2N FROM 130E TO 
155E BUT CURRENTLY CONTAINS VERY LITTLE ACTIVE WEATHER WITH IT. 
HOWEVER...CONVERGENCE IN THE TRADE-WIND FLOW NORTH OR THE TROUGH 
EXTENDS FROM 5N140E THROUGH 5N150E TO JUST SOUTH OF POHNPEI NEAR
5N157E AND IS HELPING TO SUPPORT SOME AREAS OF SCATTERED SHOWERS AND 
ISOLATED THUNDERSTORMS PRIMARILY BETWEEN 140E AND 150E...WHICH IS 
WEST OF CHUUK. EAST OF POHNPEI AND INTO THE MARSHALLS...TRADE-WIND 
CONVERGENCE IS AIDED BY A WEAK SURFACE TROUGH IN THE VICINITY OF 
KOSRAE CREATING A LARGER AREA OF SCATTERED SHOWERS AND ISOLATED 
THUNDERSTORMS BETWEEN 3N AND 8N FROM 158E TO 171E. FINALLY WEAKER 
SHOWERS EXISTS IN THE CONVERGING TRADES FROM 171E TO THE DATELINE 
OVER THE SAME NORTH/SOUTH EXPANSE.  

$$

EDSON