(Bloomberg) -- The historic drought stretching across California and the U.S. West will likely last through October, with only minor improvements expected in parts of Arizona and New Mexico.

Drought now covers almost 95% of 11 western states, including all of California, Nevada, Arizona, Utah, Oregon and Idaho, according to the U.S. Drought Monitor. Above-normal temperatures and a dearth of rainfall is expected from August to October, according to the National Oceanic and Atmospheric Administration’s monthly report.

Driven by record-high temperatures, drought has already cost more than $1 billion, according to the National Centers for Environmental Information. The parched landscape has created water shortages for farmers and communities, crimped hydroelectric generation and raised the risk of wildfires.

“Drought over the western U.S. is expected to mostly persist,” Dan Collins, a meteorologist with the Climate Prediction Center, said during a conference call with reporters Thursday.

The temperatures are setting more records from coast to coast, with the contiguous U.S. having its warmest June in the 127-year record. California, Nevada, Idaho, Utah and Arizona are also having record hot months. In the East, so did Massachusetts, New Hampshire and Rhode Island.Recent rains for the annual monsoon in Arizona and New Mexico have caused floods, but will help improve conditions, Collins said.

While the monsoon has sparked flash flood warnings across parts of Arizona, New Mexico and Utah Thursday, the rain isn’t expected to be above average or wash away drought concerns, he said.

©2021 Bloomberg L.P.