A frost advisory was issued by the NWS San Francisco CA on Thursday at 2:57 a.m. The advisory is for North Bay Interior Valleys, East Bay Interior Valleys and Santa Clara Valley Including San Jose.

Temperatures in parts of the San Francisco Bay Area were expected to drop into the upper 20s to the middle 30s for the second morning in a row Tuesday, triggering a Freeze Warning and Frost Advisory.

The eventual U.S. departure further threatens the central goal of the agreement to avoid a rise in global temperatures of 1.5 degrees Celsius, a target that appears even more tenuous as last year was the planet's hottest on record.