San Diego Weather
Chapter 1: Legendary San Diego Weather from our Ebook – Choosing where to retire… why not San Diego? Get your free copy of our latest ebook to complete reading all the chapters.
So we’ll start off with one of the most obvious concerns. The first benefit is saying goodbye to frigid, snow-filled winters… forever! And while we’re at it, let’s toss out even the unseasonable spring and fall weather and even blistering summers too. We could probably stop right there. But taking it a step further, San Diego has the best weather in the United States!
So wearing shorts and sandals all year round is no problem! And of course low humidity, no rain and lots of sun is enticing for almost anyone. That also means San Diego is practically mosquito-free! It might seem hard to back up claims saying San Diego has the “best weather,” but guess what… the statistics don’t lie.
A Mediterranean climate, with very little rain, storms or humidity… it’s completely different than places like Florida and other tropical climates (where the hurricanes, humidity and rains can keep you trapped indoors).
The weather is directly affected by the colder waters of the Pacific Ocean. The result is cooler summers and warmer winters vs. other areas of the same latitude (Louisiana, Alabama, Mississippi and Georgia).
It’s extremely rare to ever see temperatures below freezing, but at times temperatures do rise above 90° F.
In the eastern sections of San Diego, dry, easterly winds called “Santa Anas” can blow for several days at a time and temperatures climb into the 100’s. But overall there are very few days with weather this hot. These winds happen more in the fall season, and generally the hottest weather is in September and October. However, the high temps always seem to correspond to very low humidity (below 20%).
San Diego County
Over 4,200 square miles (roughly the size of Connecticut), it’s broken into regions: central, south, east, north central, north inland and north coastal counties.
San Diego County is cushioned between the Pacific Ocean on the west and the Colorado Desert (including the Palomar and Laguna Mountain ranges), on the east border. The desert portion covers roughly 1/3 of the county. It’s bordered to the south by Mexico, and to the north by Riverside and Orange Counties.
The area is known for wide ranging temperatures within short distances. Most of the coastal climates rarely fluctuate by 15°F between highs and lows, but as you move only a few miles east, inland areas can increase these ranges by 30°F or more.
THE 4 CLIMATE ZONES OF SAN DIEGO COUNTY – COASTAL, INLAND, MOUNTAIN & DESERT
The average monthly temperatures range from a low of 57.3°F (14.1°C) in January to a high of 72°F (22°C) in August. Late summer and early fall is the hottest time of year, where temperatures can rise above 90°F (32°C).
The all-time record high was 111°F (44°C) on Sept. 26th, 1963 and the all-time low of 25°F (-4°C) on Jan 7th, 1913.
San Diego Weather VS. National Averages
- San Diego averages only 21 days with some precipitation VS. the average of the rest of the U.S. with 110 days!
- San Diego averages 267 mostly sunny days VS. the rest of the nation, only 213 days.
- San Diego averages only 2.5 days above 90°F (32°C) VS. 37.9 days nationally.
- San Diego averages 0 days below 32°F (0°C) VS. 88 days nationwide.
- San Diego’s average low is 50°F (10°C) VS. 26.5°F (-3.1°C) nationwide.
- San Diego’s average high is 76°F (24°C) VS. 86.8°F (30.4°C) nationally.
Climate Zone and Weather Patterns
San Diego is located in a “Climate Zone 3” environment – a temperate weather classification. Compare this to the Climate Zone 1 of Florida, a tropical, humid environment with the most rain and highest temperatures.
Southern Oscillations influence San Diego weather patterns. El Niño brings more precipitation and humidity in the winter than the rest of the year. And the La Niña phase brings drier, cooler and less humid conditions in the summers.
Strong Winds and Tropical Storms Are Very Rare
The colder temperatures of the offshore currents protect San Diego from hurricanes and tropical storms. Most storms originate in the South Pacific Ocean and move northward towards San Diego. But they tend to dissipate as they reach the Baja California region of Mexico and rarely bring any rain to the area.
The last known hurricane to make landfall in San Diego was in the year 1858, and two smaller tropical storms were also recorded in 1939 and 1976. Compare this to other US cities of similar latitudes, like New Orleans, where hurricanes are a much more frequent.
Snow is Pretty Much Unheard Of
Snow has only been recorded 5 times in the past 125 years in the lowland communities of San Diego. In winter, light snow is a little more common in the mountains of east and north San Diego county (at elevations above 3,000 feet, or 910 meters).
Hail has also been recorded very rarely.
Source: National Weather Service – www.wrh.noaa.gov/sgx/climate/san-san.htm
Rainfall in San Diego
On average there are 41 days of measurable precipitation. The annual average of precipitation is less than 12 inches (300 mm), the lowest amount on the U.S. west coast. In general, most of the precipitation falls in the winter months. 85% of rainfall occurs from November to March, and the mountain areas can have thunderstorms more frequently.
San Diego averages 146 sunny days and 117 partly cloudy days per year… or 263 days with sunshine.
There’s virtually zero rain in the summer months, however occasional thunderstorms and humidity pop-up for a few days. The driest areas are the lower elevation areas like El Cajon and Poway, toward the east. The coastal cities are also very dry. The far inland areas have more rain, and the Laguna Mountain areas average more than 30 inches of rain per year.
An idea of historical rainfall patterns…
1941 – Wettest Year: 24.93 inches of rain (63.3 cm)
Wettest Month: 9.9 inches (23.1 cm) – January 1993
Wettest Day: 3.23 inches of rainfall in 24 hours (8.2 cm) – April 5, 1926 1953 – Driest Year: 3.23 inches of rain (8.2 cm)
May Gray, June Gloom
Most of the Pacific Coast, including San Diego, experiences nighttime and early morning cloudiness. It’s especially noticeable in the spring and summer. Low lying clouds, called the marine layer, form over the coast and extend inland over the coastal valleys and reaching the foothills.
Not to worry… San Diegans still enjoy beautiful, clear afternoons even after the cloudiest mornings. Most days, you can count on the cloudiness burning off by the late morning. This phenomenon is strongest in the months of May and June, and hence the expression “May Gray, June Gloom” is born.
Fog can be common along the coastline, especially in the fall and winter. But any fog decreases significantly as you move inland.
Beware, People Tend to Get a Little Spoiled Here
The annual range of temperatures, number of sunny days, with low humidity, low rainfall, and low frequency of storms… the facts speak for themselves.
The bottom line is… the weather is so nice you’ll hardly worry about what to wear before stepping outside. Not many places in the U.S. can claim that!
San Diegans might start to complain about temperatures lower than 65°F… and when that seems too cold you know you’ve got it good! Or when the A/C units turn on when temperatures get above 75°F, it a sign that you’re probably a little spoiled!