March is a shoulder month in San Francisco, the turn from the wet winter toward the dry summer. It is the last month with dependable rain, averaging about 3.1 inches, but it is also when the weather starts turning warmer and clearer. Highs average 62°F, about four degrees warmer than January. The days are much longer, too, with sunset after 7:15 PM by the end of the month. March is when San Francisco stops feeling like winter and starts hinting at spring.
How Much Rain Does March Get?
March averages 3.15 inches of rain on about 10 rainy days, which makes it the fourth-wettest month after December (4.76 inches), January (4.40 inches) and February (4.37 inches). March storms also tend to be different from midwinter ones. The big atmospheric rivers of January and February start to taper off, and March storms are often shorter and lighter. A March storm might bring half an inch over a morning rather than 2 inches over two days.
March rain does not fall evenly through the month. Some Marches are wet from start to finish, while others get almost all their rain in the first two weeks and then turn dry and warm. March 2023 was an outlier, with atmospheric river storms continuing well into the month after a very wet winter. In some drought years, March brings less than an inch. Because it varies so much, check the forecast before a March trip rather than relying on averages.
What Are March Temperatures Like?
March highs average 62°F and lows 49°F, so nights are mild by national standards. The days are comfortable for walking, hiking and eating outdoors with a light jacket. The warmest March days can reach the upper 60s or even 70 degrees during brief warm spells, usually when high pressure builds and the wind turns offshore.
March also brings a stronger sun, which feels noticeably warmer than January sun even at the same temperature. Daylight saving time starts in the second week of March and adds an hour of evening light, which makes the month feel warmer than the numbers suggest. It is when many San Franciscans start eating dinner outside again.
Wildflowers and Green Hills
March is the peak month for green hills and early wildflowers in the Bay Area. Winter rains have soaked the ground, and the warming days drive fast growth, so hills that were golden brown all summer and fall turn vivid green. California poppies bloom at Lands End, on Mount Tamalpais and across the Marin Headlands. Lupine, buttercups and mustard add purple and yellow to the grassy slopes.
That makes March one of the best months for hiking in the Bay Area. The air is clear after the winter rains and the views are long. Trails are green and in good shape, and the cool air is comfortable for hard effort. The summer fog has not arrived yet, so coastal trails that will be gray and cold in June are often sunny and pleasant in March.
Fog and Wind in March
There is little fog in March, because the Central Valley has not started its summer heating and nothing is pulling marine air hard onshore. Marine layer fog can still form along the coast on some mornings, but it is usually thin and burns off quickly. The wind is moderate as well, usually a gentle 10 to 15 mph in the afternoon. The strong summer winds that blast through the Golden Gate at 25 to 30 mph are still a few months away. That is enough to justify a windbreaker but not enough to spoil time outdoors.
March sits in a sweet spot, with the wet season winding down, the fog season not yet started and the landscape at its most beautiful. It is not the warmest month, and you will probably get rained on at least once. Still, green hills, wildflowers, mild temperatures and clear air make it one of the most underrated months to visit. Bring a rain jacket and a camera, and expect both sunshine and showers on the same afternoon. For the drier, windier month that follows, see San Francisco weather in April.
