60. 



20.0 - 



RETURN PERIOD IN YEARS 

 5 10 20 40 60 



100 



^ 0.0 



.0 50.0 80.0 90.0 95.0 98.0 99.0 



CUnULflTIVE PROBABILITY SCALE 

 EXTREMAL TYPE I 



Figure CI 7. Gulf of Alaska, 30-hr averages 



99.9 



CIO 



