Millions of heat-battered Americans are eagerly awaiting a Canadian cold front expected to soon break the back of a record-setting heat wave blamed for at least 30 deaths and untold suffering across large swaths of the central and eastern United States.

There are reports of buckled highways, withered crops and power outages from Wisconsin and Kansas to the Atlantic coast. Authorities have issued a string of excessive heat warnings ahead of blistering temperatures smothering about half of the country. Ten deaths in Chicago alone have been tied to the unforgiving temperatures.

In Washington Saturday, temperatures pushed past 40 degrees Celsius, as many outlying residents remained without power more than a week after deadly summer storms battered the region. Utility companies still grappling with the disaster are urging consumers to conserve energy, as the ongoing heat strains power grids along much of the East Coast.

The National Weather Service says relief will likely be felt by Monday, as a cold wave begins pushing temperatures below seasonal averages in much of the Midwest and Mid-Atlantic states.

Forecasters say strong storms are expected to accompany the front, and may cause more problems in states still struggling to recover from last week's killer storms.

The sweltering weather, spawned by a stationary high pressure system, has broken nearly 5,000 daily heat records and more than 260 all-time heat records nationwide in the past 30 days.