The many Iowans who plan a car trip for the upcoming holiday weekend could find the weather causing headaches, depending on which direction you’ll be driving to Grandma’s house. Forecaster Brian Pierce inthe Quad-Cities office of the national weather service says the latest update this Monday is quite different from previous forecasts, and it’s still unclear what the weather pattern will be by the time millions hit the road in the middle of this week. There will be major storm systems affecting “part of the Midwest,” but newest projections show them pushing farther to the south and east. Pierce says earlier forecasts called for rain over most of the state changing to snow on Wednesday, a potential nightmare for road travelers. The update might be good news. It more or less depends on where you are — if you’re heading north or westward you’ll have a good change of clear conditions, if you head east or south you’re more likely to run into something. Pierce says there’s little doubt some kind of precipitation will cover part of the state within a day or two from now. It will probably start out as rain, and it all depends on when cold air comes in — he says it’ll mean some of the rain turns into snow. Icing in the falling temps could be the most dangerous outlook, but the meteorologist says there’s a good chance we’ll avoid that. He says the temperature of the ground and the roadway surfaces have still been fairly warm, though they’ve been solling over the past couple weeks. Any weather system that begins as rain and turns to snow is still likely to melt when it hits the road, though it could be a problem if the snow gets heavy. Travelers should check in for weather updates, tune in radIo reports on the roads, and on the web you can surf to: