Why June gloom besets San Diego

The Catalina Eddy, a meteorological condition responsible for days-long episodes of dreary, overcast weather over San Diego, is most likely to occur in May and June. This weather pattern, which intensifies our late-spring “June gloom,” happens when moist marine air, drawn inland from the area around Santa Catalina Island, condenses in the form of low clouds along the Southern California coastline. The summer-like episodes experienced along the coast in recent weeks should prove but an odd prelude to the usual cool, humid late-spring weather yet to come.

Residual Moisture in the Ground left over from the wet winter season has delayed, for perhaps a month, the inevitable springtime “brownout” of San Diego’s coastal vegetation. The wild oats and foxtails have mostly turned gold, but other varieties of wild grass such as rye remain green in some areas. Yellow waves of wild mustard continue to put on a good show here and there, especially on the steep slopes and road cuts overlooking several of the freeways.

Chamise and Buckwheat, two of the most common native flowering plants in San Diego County’s sage-scrub and chaparral plant communities, are in flower this month through June. Chamise, also known as greasewood, readily sprouts from root crowns after fire. Much of the area between the Laguna Mountains and El Cajon, swept by the mammoth Laguna Fire of 1970, is now smothered by chamise four–eight feet high and buckwheat two–three feet high. A few years hence, the even larger area burned in the 2003 Cedar blaze will again be covered by this dominant type of vegetation. The stems of both chamise and buckwheat are tipped by clusters of small white or cream-colored flowers, fading to russetbrown by July. Near the coast look for flat-top buckwheat, common on south-facing slopes. Here it shares space with other low-growing sage-scrub plants like black sage and California sagebrush.

Now comes the crescent Moon back to the evening sky, higher and bolder in the western twilight each evening. Watch it pair with Venus, then Mercury, then skip a beat, then Mars.

The above comes from the Outdoors listings in the Reader compiled by Jerry Schad, author of Afoot & Afield in San Diego County. Schad died in 2011. Planet information from SkyandTelescope.org.