The Bay Area concluded its historically hot March with the arrival of April showers, marking the region's first measurable precipitation since March 2. This shift brought cooler temperatures after a month defined by an unusually strong high-pressure ridge.

Record-Breaking Warmth Defines March Weather

March Sets New Temperature Benchmark

The preceding month will be remembered for its intense warmth. According to the National Weather Service (NWS), the average high temperature for March reached 62.3 degrees, establishing it as the warmest March ever recorded in the Bay Area.

This average temperature would also rank as the second-hottest April and the third-hottest May if it had occurred during those months. This sustained warmth was attributed to a thicker-than-usual high-pressure ridge dominating the weather pattern.

April Arrives with Much-Needed Rainfall

Timing and Intensity of the Rain Systems

Light rain began falling late Monday and continued overnight into Tuesday as the first of two approaching weather systems moved in. NWS meteorologist Nicole Sarment noted that the rain would not be heavy, describing it as little more than a hard drizzle.

The majority of the precipitation is anticipated on Wednesday when the second system replaces the first as it moves south. Sarment detailed that this second system is a "true Gulf of Alaska low," bringing a trailing cold front that will lower temperatures and snow levels.

Regional Rainfall Totals Expected

The entire region is expected to see slightly heavier rain on Wednesday, though most areas will experience light accumulation. Higher amounts are projected for the Peninsula and the North Bay Coast, potentially receiving up to a half-inch of rain.

Elevations in the North Bay could see up to an inch of precipitation. Conversely, the South Bay and interior East Bay are forecast to receive approximately one-tenth of an inch. High temperatures are expected to remain in the low 60s during this period.

Quick Return to Warmer, Drier Conditions

The wet weather is expected to be brief. Meteorologist Sarment indicated that Thursday morning would present the final opportunity for rain.

Following that, conditions will rapidly warm and dry out heading into the weekend. An offshore flow is predicted to enhance the warming trend, though Sarment noted uncertainty regarding how long the high-pressure ridge will persist.

Winter Weather Advisory Issued for the Sierra Nevada

The pattern change is also set to bring snow to the Sierra Nevada mountains. A winter weather advisory is scheduled to take effect from 5 a.m. Wednesday until 8 a.m. Thursday.

Near the Sierra crest, including Donner Pass, 5 to 10 inches of snow accumulation is possible. Valleys in the area could see 1 to 4 inches of snow. Wind gusts are forecast to reach as high as 100 mph at the crest and 45 to 55 mph in the valleys.

Travel conditions are likely to be impacted, especially on Interstate 80 and state Highway 50. Motorists are advised to exercise caution and monitor conditions. Waves on Lake Tahoe are expected to range between 1 and 4 feet high.