Daytime snowfall, however light, seems to create utter panic in Washington -- a situation exacerbated by the number of people who drive rather than use public transportation, as well as by the longer drives created by ever-widening metropolitan sprawl.

Wednesday's brushing of snow, by all accounts, sparked an utterly inexcusable early exodus of many federal workers who ignored pleas by traffic officials that they wait until highway crews had time to lay down sand or salt.

One federal employe told me that so many spouses had called by midafternoon saying the snow was coming down heavily in Vienna, Gaithersburg and elsewhere that scores of his colleagues decided to hurry home. This employe, a subway user working flexitime, was virtually alone in the office two hours before the normal closing hour.

A lot of departing people, I'm told, said they didn't believe the conservative weather forecast and recalled such horrors as the traffic jam during a weather emergency in December when the rush hour lasted until after 8 p.m.

Three reasons the rush hour lasts so long during snow panics are that (1) early departures disrupt the normal and very sensitive pattern of traffic in the downtown area, (2) traffic signals aren't set and public transit isn't prepared for unsanctioned early departures and (3) snow clearance or sanding haven't been completed.

So, in situations such as on Wednesday, leaving for home early only makes the rush hour worse -- and diminishes government productivity.