Smoggy Days Ahead
The smoggiest days of the year are most likely to occur during the next two months. Persistent temperature inversions (warmer air overlying cool marine air) are frequent this time of year. These inversions conspire with the mountainous topography of East …
Escaping the Heat of the Santa Anas
Late September or Early October signals the beginning of Santa Ana winds, which may continue intermittently through the winter. Early Santa Anas are often responsible for coastal San Diego's hottest and driest days of the year. Records show that 62 …
Autumn Arrives
Fall Officially Begins at 2:19 p.m. Pacific Daylight Time on Tuesday, September 22 -- a good excuse to throw, a few hours later, an impromptu "equinox party" to celebrate the occasion. At equinox, the sun shines directly down somewhere on …
Zodiacal Light
The Zodiacal Light, which can appear as a diffuse, pillar-shaped glow in the eastern sky for up to an hour before dawn, will be quite conspicuous at dark locations this weekend (September 19-20) through next weekend (September 25-26). The subtle …
Crescent Moon and High Tide on Wednesday, September 16
The Highest Tide for September (a not-very-high +6.2 feet), is predicted for 8:10 p.m. on Wednesday, the 16th. The month's lowest tides (a not-very-low minus 0.6 feet) will occur on the mornings of the 16th and 17th at 2:04 a.m. …
Sunset in Rapid Decline
The time of sunset changes most rapidly this time of the year. This is mainly because the sun is swinging rapidly south along the ecliptic (its apparent path through the background stars). From the latitude of San Diego, the sun …
Fall Migrant Birds
Wood warblers and other fall migrants can be seen at Cabrillo National Monument and its vicinity on Point Loma, Torrey Pines State Reserve, and other parks and open spaces near the San Diego coast. Cooper's or marsh hawks and even …
Chaparral Activity
The chaparral, the tangled assortment of low-growing, drought-resistant, native shrubs covering much of San Diego County's lower mountain slopes, has managed to remain fairly attractive this summer. Unlike many of the scrubby natives near the coast, chaparral plants tend to …
East County Thundershowers Spur Vegetation
Summer thundershowers, having blessed the eastern margin of San Diego County with welcome, if spotty precipitation of late, have triggered a minor growth spurt among certain kinds of vegetation. In the desert, for example, the spidery ocotillo can grow an …
Shore Birds Arrive
Shore Birds migrating southward are beginning to arrive in San Diego County. Through fall and winter various ducks, sandpipers, and plovers will be spotted in increased numbers in the county's coastal wetlands. Best bird-watching spots include the Tijuana River estuary, …