Lindbergh Field posted a record high temperature of 85 degrees Wednesday, breaking the March 4, 1968, mark of 83.
But a 50% chance of rain is expected to wash away the heat late today, National Weather Service forecasters said.
Heavy showers are expected to linger through Friday morning, bringing one or two inches of rain to the coast before the Pacific storm moves slowly eastward, making way for a sunny weekend, forecaster Wally Ciegel said.
Skies will remain mostly cloudy Friday throughout the county, with high temperatures along the coast ranging from 63 to 68 degrees. Beach highs will range from 60 to 65 degrees. Ocean water temperature will be near 57.
Inland valley highs will range from 70 to 76 today, decreasing slightly to 65 to 71 degrees Friday. A 40% chance of rain Friday is expected for the inland valleys.
Mountain skies also will sport clouds Friday, with a chance of showers. High temperatures will range from 46 to 54 degrees, with low temperatures registering from 34 to 42.