Summer is almost here. What kind of weather can SLO County expect?

As we head toward the summer solstice on Saturday, June 20, the Earth’s orbit will bring the North Pole to its most considerable exposure to the sun due to the 23 ½-degree tilt of the Earth on its axis.

This 23 ½-degree tilt not only drives the seasonal variations in the weather but also produces additional uneven heating of the Earth’s surface. The angle also causes differentials in pressure, which give rise to the winds and storms.

It may seem contradictory, but in the Northern Hemisphere, the earliest sunrise of the year occurs about two weeks before the first day of summer with the longest day and shortest night of the year.

Conversely, the latest sunrise occurs about two weeks after the summer solstice.

This discrepancy can be visualized by the “equation of time” graph on a sundial that looks like a lopsided infinity symbol turned 90 degrees upward.

This graph reconciles the difference between apparent solar time (sundial) and mean solar time (clock).

If you happen to be north of the Arctic Circle on June 20, the sun never sets but remains above the horizon.

Further south in Chicken, Alaska, the sun drops below the horizon near midnight and comes back up about 3 a.m. You will only see a few hours of twilight.

At our Central Coast latitude, the sun will rise at 5:49 a.m. and will set at 8:21 p.m. That gives us about 14 hours and 21 minutes of daylight, the longest day of the year.

If you travel south to the equator, you always have 12 hours of light and 12 hours of darkness, regardless of the time of the year.

The South Pole’s axis is tilted almost directly away from the sun in the Southern Hemisphere, which marks the first day of winter and perpetual darkness.

The word “solstice” means “the sun stands still” in Latin. The sun has been moving north each day, leading up to the summer solstice.

On June 20, the sun will appear to stand still. It will reach as far north as it will go.

The next day it will start its journey south until the first day of winter for the Northern Hemisphere in late December.

So, what is the weather outlook for summer?

Stronger than average northwesterly winds, less marine low clouds with mist and fog and cooler seawater temperatures along the immediate shoreline and above-average temperatures away from the coast are forecast throughout California in July, August, and September.

We are now passed the so-called “spring predictability barrier.”

You see, in spring, the El Niño Southern Oscillation (ENSO) is often in the transition from one phase to another.

For example, an El Niño condition could be decaying and passing through neutral condition to a La Niña phase, or vice versa. Overall, in spring, the models can show an enormous amount of variation.

This week, NOAA’s Climate Prediction Center continues to advertise that the infamous neutral condition — known as “El Nothing” or “El Nada” — will continue through the summer. Unfortunately, a few of the models are venturing into La Niña territory.

Sea surface temperatures (SST) in the central equatorial region of the Pacific Ocean called Niño 3.4 are the standard for classifying El Niño-warmer-than-normal sea surface temperatures (SST) and La Niña (cooler-than-normal SST) events.

Since 1950, NOAA has used SST to categorize by the amount temperatures deviate from the average, in other words, an anomaly.

Unfortunately, neutral and La Niña conditions typically produce lower-than-average winter rainfall during the year. However, there have been neutral and La Niña years that have produced well above average rainfall amounts.

PG&E fire safety tips

With the increased wildfire threat our state faces this year, PG&E is enhancing and expanding our efforts to reduce wildfire risks and keep our customers and communities safe. To lean how you can prepare, please visit www.pge.com.