STATE AND LOCAL officials needn't wait for President Carter's announcement of his energy plan next week to establish a rational set of rules for handling gasoline shortages. They should do it now, before regions around the country wind up in chaos as a result of isolated and often contradictory local decisions. This time around, area governments should move quickly to collaborate on some reasonably uniform policies for gasoline allocations and sales.

Only consider what happened last time around very near to home, when five years ago motorists discovered that buying gasoline was truly a tricky, frustrating and haphazard mission. The temptation was to hoard, to scramble from station to station for a full tank at all times. Some stations were pumping all day in some areas while nearby there were stations not pumping at all. They also imposed their own varying limits on purchases, some in dollars and some in gallons. Lines were long at some pumps, nonexistent at others. Only belatedly did officials in the District, Maryland and some suburban Virginia governments try to coordinate their responses.

There is still the possibility that Virginia Gov. John N. Dalton, Maryland Gov. Harry R. Hughes, District Mayor Marion Barry or the various suburban leaders around the region could come up with 101 rules for gasoline sales, from never-on-Sunday to odd-numbered dates for odd-numbered plates. That kind of patchwork of plans, experiments, proposals, requests and voluntary initiatives is not the proper solution for any metropolitan region. Fortunately, the two governors and the mayor do seem to be working out some general agreement.

If the needs of Southside Virginia call for a different response from Northern Virginia, there can be adjustments. But specific agreements can and should be reached, for example, calling for staggered hours at stations throughout the region rather than evening sales in one state, midday closing in another and license-tag rules downtown. We also think the Sunday ban is a bad idea; for one thing, it invites motorists to fill up cans and carry them along in trunks or back seats -- which is plain dangerous. Whatever Mr. Carter's plans entail, each government in this region should join now in an area-wide, workable response.