Hawaii

Hawaii was the location of a relay station for the Snowcap space tracking station. It was known to be in active operation during at least the month of December 1986. (DW: The Tenth Planet)

In December 1999, snow was reported as falling in Hawaii (DW: Doctor Who) as the result of The Master's opening of the Eye of Harmony. (EDA: Unnatural History)

Behind the scenes

 * It's unclear that Hawaii has ever been referred to as a state in Doctor Who fiction, though it's unlikely that a local American news broadcast, like the one seen on KKBE, would be referring to Hawaii unless it were a state, thus allowing them easy access to weather reports and video footage.
 * The reference to snow in Hawaii being unusual is somewhat difficult to parse, as there's almost always snow on the Big Island of Hawaii, year round.