Sun, Clouds and Fog. Photo Credits: Top Left: NPS photo; Top Right & Bottom: Jessica Weinberg, NPS.

While the term “climate” is used to describe long-term meteorological trends, “weather” occurs on a shorter time scale (from minutes to months). As anyone who has traveled from the east or south bay into the city on a summer day can attest, the weather in different parts of the San Francisco Bay Area can vary dramatically. In the summer, warm moist air traveling east collides with cold coastal waters along shore, cooling the air and condensing the moisture in it. This condensation creates the blankets of fog that this area is so well known for in the city, and along the headlands and outer coast. Within the Point Reyes peninsula, weather can vary greatly between both sides of the Inverness Ridge, with inland summer temperatures often 20 degrees warmer than those on the coast. The weather at Pinnacles National Park is a bit more typical of the Mediterranean climate of California, with cool wet winters and hot dry summers.