Storm chances up for midweek; precipitation type still a pesky question Posted at 03:15 PM ET, 03/02/2013 Odds are increasing the Washington, D.C. area will see a period of precipitation Tuesday night into Wednesday or Wednesday night. And if the precipitation is heavy enough, then this looks to be our best chance of significant snow all winter long. That is still a big "if," however. So while our chance of at least 1 inch of snow is up from yesterday, it remains below 50/50 for the time being: Next chance of accumulating snow: Tuesday night-Wednesday night Chance of at least 1 inch: 40 percent (up from 30% yesterday) Keep reading for more details... Today's models continue to advertise the potential for a significant storm across the mid-Atlantic Tuesday night through Wednesday night, including in the Washington, D.C. metro area. Possible scenarios include: 40% chance: A minor to moderate storm producing ~1-4" of snow, likely mixed with rain and perhaps some sleet 35% chance: A storm that is mainly rain with little to no snow or sleet accumulation. 25% chance: A moderate to major storm producing ~4" or more of snow, possibly starting as or mixed with rain and/or sleet. After a few days of models flip-flopping between a storm that might track too far to our south for significant snow, to one that might ride up the coast and give the big cities along the I-95 corridor including D.C. a major winter storm, models now seem to be converging on a storm that will bring a period of precipitation to much of the mid-Atlantic but then head out to sea rather than up the coast. Last three runs of the GFS weather model have trended heavier precipitation north into the D.C. area (NOAA) While the odds of a major Nor'easter that would turn up the coast and wallop Philadelphia, New York and Boston are down, they are not completely out. Similarly, there's still a chance the storm slides mainly south of the D.C. area, but likewise those chances are decreasing. So with the overall trend pointing toward significant precipitation locally, the big question is whether it will be heavy enough to pull down cold air from the mid-levels of the atmosphere and support accumulating snow. If precipitation is too light, then temperatures here near the ground would probably stay above freezing, which combined with a strengthening March sun would limit the potential for snow and especially accumulating snow. Right now we're *leaning* toward at least some accumulating snow, especially for colder areas west of I-95, and the best chance we've had all winter of seeing more than 1 inch. Of course that's not saying much given the winter we've had, and it's not a terribly confident "lean," either. Here's what our winter weather expert Wes Junker had to say after reviewing the latest information: The range of possibilities seems to be narrowing as today's models are now predicting significant precipitation across the region. The most likely scenarios now are a more significant storm that produces some accumulating snow especially for folks west of I-95, or or storm that produces modest precipitation primarily in the form of rain. The models continue to vacillate between solutions that would bring the heaviest precipitation right through the area giving us a better chance for at least some accumulating snow, and those that would keep the heaviest precipitation just to our south likely meaning mostly rain. This is one of those cases where the precipitation gradient (how quickly it drops off from south to north) is greater than normal, so only slight shifts in the track of the storm's low-pressure center can make significant differences in the amount of precipitation we get.