Monday is Northern Hemisphere Hoodie-Hoo Day. It was dreamed up by a guy who thought people oppressed by winter should hasten its end by running into the streets shouting "Hoodie-Hoo!" That could be amusing, but the last time it snowed in downtown L.A. was in 1949. So we suggest you mark the holiday with 1991's "L.A. Story." Steve Martin, at right, plays a TV weatherman weary of climatic consistency. Dallas Raines (who to our knowledge has never ordered a half double decaffeinated half-caf, with a twist of lemon) can relate. "I hate to admit it," says the Channel 7 meteorologist of his job, "but it can be kind of boring."