Climate and Weather

The climate of Pinnacles is typical of the Mediterranean climate of California, with cool wet winters and hot dry summers. Average rainfall is 16 inches per year, falling mostly from January through March. Winter climate is akin to the California deserts, with mild days and nights often dropping into the low 20s. Snow occurs in small amounts at higher elevations almost every year between mid-December and January. Summer temperatures of over 100°F are common, but coastal fog will often come into the valleys at night. Nighttime summer temperatures of 50°F are common, making for enormous daily temperature swings.

 

What's the difference between climate and weather?

Weather describes day-to-day conditions, short term variation in minutes to days. We think of weather as a combination of temperature, humidity, precipitation, cloudiness, visibility, and wind. We talk about changes in weather in terms of the near future: "How hot is it right now?" "What will it be like today?" and "Will we get a snowstorm this week?" 

Climate describes longer-term weather patterns. It is the weather of a place averaged over a period of time, often 30+ years. We talk about climate change in terms of years, decades, and centuries.

You can think of climate and weather in terms of your clothes closet. Each day you choose one outfit to wear, depending on the season and your mood. That's weather: the day to day thing we see. When you look at your wardrobe as a whole, that's climate. You might have a silly costume you wear for special occasions, but that's not representative of who you are all of the time. So although extreme weather events do affect the overall climate of a place, one or two extreme events do not describe the entire climate. Climate is the bigger picture that includes both normal patterns and how often more extreme events occur in both directions.

 

Wet and Dry Cycles

The great variability in seasonal precipitation is due to the east Pacific high. This dominant weather feature shifts northward in the summer to shunt storms far to the north. Occasionally this feature brings subtropical moisture into central California from southerly latitudes, producing one to five thundershowers per year in the Park. Mostly, however, the east Pacific high acts as a giant valve completely shutting off precipitation for long stretches of the year.

California is known for its long dry and wet cycles. Changes in the East Pacific high shift on approximately a six-year cycle. The result is persistent drought for five to eight years, followed by a wet period. Such cyclic variation is an important consideration in vegetation, wildlife, and water management.

Geographic Context

Although the park is only 40 miles from the Pacific Ocean, the Santa Lucia Mountains to the west modify the ocean influence before it reaches Pinnacles. While on the coast summer temperatures might be a fairly steady 60 degrees Fahrenheit, at Pinnacles the temperature can swing from 50 degrees at night to 100 degrees during the day. Similarly, without the ocean’s warming effect, winter temperatures at Pinnacles often drop below freezing while coastal temperatures remain moderate.