I think Wikipedia may have meant "West Coast", not "East Coast"
http://en.wikipedia.org/wiki/K...
"These climates have an average temperature above 10 °C (50 °F) in their warmest months, and a coldest month average below −3 °C (or 0 °C in some versions, as noted previously).
These usually occur in the interiors of continents, or on their east coasts, north of 40° North latitude.."
"Dsc, like Dsa and Dsb, is confined exclusively to highland locations near areas that have Mediterranean climates, and is the rarest of the three as a still higher altitude is needed to produce this climate"
s indicates dry summers (June, July and August in northern hemisphere?) (driest summer month less than 30 mm average precipitation and less than one-third wettest winter month precipitation)
a indicates warmest month average temperature above 22 °C (72 °F) with at least 4 months averaging above 10 °C (50 °F),
b indicates warmest month averaging below 22 °C, but with at least 4 months averaging above 10 °C,
while c means 3 or fewer months with mean temperatures above 10 °C.