The National Weather Service says another winter storm is heading toward northwestern Oklahoma and could eventually make its way into northwestern Arkansas.
   The weather service in Norman has issued a Winter Storm Watch for Sunday night through Monday night for the northern tier of counties in Oklahoma. The weather service in Tulsa says the storm could continue through northeastern Oklahoma and into northwestern Arkansas late Monday and early Tuesday.
   The weather service says six to 10 inches of snow and blizzard-like conditions are possible in northwestern Oklahoma while up to four inches of snow is possible in northeastern Oklahoma -- extending into northwestern Arkansas.
   The latest storm comes on the heels of a storm that brought snow, sleet and icy conditions to the two states last week.