Ask a Canadian: There are two seasons in California: Green and Brown

People tend to imagine life in California as all surf, sand and sun, set against a backdrop of neverending blue skies and lush coastal mountains. They wouldn’t be wrong, but anyone who has lived here for a full calendar year knows that’s not entirely the case.

In my opinion, the Bay Area is best described as having two seasons: green and brown.

And I’m not that far off, according to the Great and Powerful Internet, which states the Bay Area has two very distinct wet and dry seasons, not unlike the Mediterranean.

The “green” season lasts for roughly six to seven months of the year, beginning in October and ending in April. This is when the Bay Area (and really the entire state of California) gets most of its annual precipitation (just over 80%). The amount can vary from mere millimetres to flooding of biblical proportions. When it comes to rainfall, it can be feast (more rain than the rivers, lakes, creeks and reservoirs can hold) or famine (drought).

The Santa Cruz and Diablo mountain ranges that run north-south, on either side of San Francisco Bay are verdant, in shades of chartreuse and emerald. It is stunning to behold. The rolling hills of the Diablo range to the east don’t have that many trees, but they are speckled with grazing cows and sheep. 

To the west of the Bay, the Santa Cruz mountains are dark and brooding with a heavy tree canopy of madrones, redwoods and other conifers. The marine layer that rolls over these mountains sometimes gets trapped as it moves eastward giving it the appearance of a rainforest. I always imagine scenes from Gorillas In The Mist when I see these mountains from afar.


The beauty of the topography changes, almost overnight, within mere weeks, if not days, when the rain stops in April. 

The lush grasses on these hills quickly turn an anemic shade of brownish-yellow and stays that way until the rains begin again in the Fall. Those hills are crispy and tinder-dry, causing a great deal of concern for first responders who have to deal with random brush fires and wildfires, often sparked by passing cars on the adjacent highways. 

This phenomenon has become more pronounced with climate change--hotter, drier summers, which make the possibility of devastating wildfires more daunting. Droughts are also a contributing factor, and sadly, normal for California--after all so much of the State is desert. But it has become more extreme with climate change. 

The Bay Area alone has numerous microclimates. That means if you live in Marin County to the north of San Francisco the weather might be overcast and misty for the day with the sun peaking out around three for a little late afternoon warmth, while your friend down in San Jose is sweltering in the “valley” part of Silicon Valley by 10 in the morning.

In fact when tourists come to San Francisco in the summer and pack nothing but shorts, tee shirts and sundresses, they are surprised when they have to go out and buy a whole new wardrobe that resembles their Fall ensemble.

Speaking of improper wardrobe choices, don't make that mistake when heading out to the coast. Having driven the short 45-minute drive from the valley, over the Santa Cruz mountains to enjoy the seaside, we now know to bring layers of clothing as the temperature drops by about 10 degrees (celsius) on the coast. The coast provides much needed relief from the dry heat of the valley, but tropical seaside it is not.

All that hot, dry air in the Valley sucks cooler, moist air from over the ocean through the Golden Gate and over San Francisco, generating intense fog and cool summer temperatures.  The fog is so well known in San Francisco it is now endearingly referred to as Karl the Fog and even has its own Instagram account (and published book!).

That fog starts out as something called the marine layer, which sits out over the Pacific Ocean. Not being a meteorologist or climatologist, my rudimentary understanding, based on what I’ve read, is that the cold ocean air and the warm sunshine meet and create a “cloud sandwich”. Meanwhile inland, the hot, dry air starts to suck that cloud sandwich over the Santa Cruz mountains and through the Strait and that’s how Karl the Fog makes its regular appearance in the summertime.

I have found September and October to be the real summer months in the Bay Area. As a Toronto expat, signs of Fall as I know it don’t start to appear until November when the leaves begin to turn colour and there is a noticeable chill in the air that demands a cozy sweater.

I admit, I miss the four seasons. But I also must admit, I don’t miss putting on my boots, down jacket, toque and gloves for the umpteenth time when February rolls around.

Dorin Greenwood is a Toronto native and Bay Area transplant. She likes to write about her experiences, both personal and professional--especially her love of baking. Feel free to get in touch with Dorin if you have story ideas or comments to share:

The views, thoughts and opinions expressed in this article are solely those of the author(s) and do not necessarily reflect the views, policies or positions of the Digital Moose Lounge.