An early snowstorm buried the Rockies' summer greenery under a foot and a half of snow yesterday, blocking roads and causing blackouts, while cities along the Eastern Seaboard baked in record heat.

At least two persons died as flash floods from as much as 10 inches of rain gushed neck deep across parts of southern Texas.

With the official end of summer still four days away, a fast-moving storm out of Canada spread heavy snow across much of Idaho and western Montana, where it was falling as fast as an inch an hour. With 17 inches on the ground in south-central Montana and 14 inches in the suburbs of Helena, the storm pushed eastward into the northern Plains and southward into Wyoming and Colorado.

Snow depths of 4 to 10 inches were reported in Billings, Lewistown, Dillon and Red Lodge, Mont.

"This is about two weeks early," said Jack Daseler, a meteorologist with the National Weather Service in Cheyenne, where record sub-freezing temperatures of 15 to 25 degrees were expected during the night. "Something like this the first of October is not outrageous, but summer isn't even over, yet."

Gardeners covered their plants, stores set up snow shovel displays and city street crews checked their snowplows in advance of the storm.

The 8 inches of snow on the ground in Billings by noon broke the 1962 record of 6.3 inches for all of September.

But the heat wave that produced the worst drought in the Midwest since the Dust Bowl days of the 1930s continued to make news in the East.

Temperatures reached 93 in New York City, 3 degrees hotter that the previous Sept. 19 record set in 1946. Records of 94 degrees in Baltimore and Wilmington, Del., 93 in Allentown, Pa., and 89 in Boston also were set.