The Weather and You: Summer Delayed

The first half of June has been unseasonably cool and cloudy along the Coast and around or near the Bay. The persistent Marine Layer is not breaking up early but has remained until afternoon in many areas. Despite the fact that today's Summer Solstice is the longest of the year, afternoon high temperatures have suffered terribly for lack of sunshine. Maximum temperatures are running 5 to 20 degrees colder than normal, depending on how far inland you are.

The largest departures from seasonably normal temperatures are in the inland valleys, especially the Tri-Valley, including the Interstate 680 corridor from Concord to Livermore.  Leap over one more set of Coastal Hills at Altamont Pass, and the Central Valley is easily 15 to 20 degrees below average for this date. Usually, the onshore flow from the Pacific with the nightly influx of fog and low clouds oftentimes does not get past the 880 corridor and, if it does, only briefly and burns off by mid-morning.  By contrast, the coast has seen very little clearing during May and June, with many days not getting out of the 50s or low 60s. Morning and evening drizzle, along with a few scattered showers this past week, has kept the fire hazard low and, in some cases, has resulted in green vegetation in the hills lingering longer into June than it normally does.

I have been keeping weather records at my house at the north end of the I-680 corridor since 1988, and for the first half of this month, I have recorded only two days above 80, which is the first time this has ever happened I am sure this is true for some folks who also have weather stations. Current long-range forecast models show more of the same pattern next week with well below-normal highs, mostly in the 70s.