Snow, sleet and freezing rain - all the ingredients for commuter misery - were expected here this morning as a vast storm system that had already ravaged much of the Mississippi Valley pushed northeastward toward Washington.

As of about 6 o'clock last night, an accumulation of about an inch of the hazardous mixture was anticipated today, according to National Weather Service forecaster George H. Schuelein.

While the combination of the three forms of precipation is more likely, Schielein said, a possible deviation in the predicted path of the storm could confine the precipitation to snow alone.

The amount of accumulation in that event could not be immediately predicted.

As it swept toward the northeast, the storm covered a broad area from west Texas to the southern Appalachians in a sheath of snow and ice, closing schools, factories and highways.

"We are pralyzed," said Memphis police Sgt. B. G. Wainscott.

In Huntsville, Ala., Stormie Hornbuckle of the sheriff's office told United Press International: ". . . If we had strawberry, we'd have popsicles all over this town; everything is covered with ice."

Under the weight of ice and snow, seven poultry houses, containing 100,000 chickens, were crushed in Hope, Ark. Other such cave-ins were predicted and one source said the situation "could create a disaster area."

"It seems like half of the motorists in the state have run off in a ditch," said a Tennessee highway patrol officer in Nashville.

Combining to produce the snow and ice are a huge air mass from the Gulf of Mexico, which contains the necessary moisture, and a broad blanket of Arctic air that invaded the nation earlier this week, and provides the required cold.

Streaming northward, the Gulf air is forced to rise above the low-lying cold air blanket, and its moisture is wrung out, as snow, ice or freezing rain.

The exact outcome depends in a sensitive way on local conditions. Currently, forecasters expect the warm air will furnish enough moistuorecasters expect the warm air will furnish enough moistuecipitation will be snow. High temperatures here today are expected to range from 32 to 36 degrees.