Wild Lilacs, Acacias, and Winter Constellations
Ceanothus, or wild lilac, a late winter or early spring blooming native plant, could blossom profusely this month or next. Heavy rains and protracted periods of abundant sunshine produce the most extravagant displays. Blue- and white-flowering varities of ceanothus are …
Waterfalls, Tree Aloes, and the Evening Star
San Diego County's Waterfalls could be at their very best during the next month or two, depending on how much rainfall arrives. Three of the most accessible are: Green Valley Falls at Cuyamaca Rancho State Park; the falls below the …
Lowest Temperatures, Latest Sunrise, Fullest Moon, Lowest Tide
Recent Chilly Days and Nights only confirm that San Diego's lowest temperatures (according to more than a century of weather records) tend to occur during the month of January. January's mean temperature at Lindbergh Field is about 55 degrees Fahrenheit. …
Rainfall, Gray Whales, Venus, and the Short-Lived Quadrantid Meteor Shower
Highest Monthly Rainfall totals in San Diego are most likely to occur in January and February (nearly two inches each on average) according to weather-service statistics. If low temperatures accompany the typical Pacific storms of this period, there's a chance …
The Fabled Green Flash, Liquidambar Trees, and Jupiter-Mercury-Venus and the Moon in the Southwestern Sky
Liquidambar Trees, or sweet gums, the colorfully deciduous trees gracing front yards, parks, and campuses throughout the San Diego area, have been putting on a good show for the past month. The maplelike leaves of most varieties have turned from …
Winter Solstice, Hiking to High Places, Ripening Palm Fruit
Winter Solstice, the moment when the sun reaches its southernmost point on the celestial sphere, occurs this year at 4:04 a.m., Sunday, December 21. This event signals the beginning of winter in the Northern Hemisphere and the beginning of summer …
Poinsettias, Exceptional Tides, the Moon of Longs Nights, and the Geminid Meteor Shower
Poinsettias, a favorite of backyard gardeners, are now exhibiting their scarlet, petal-like bracts, just in time for the holidays. The onset of 14-hour-long nights triggers their behavior: In San Diego this condition is met just before the date of winter …
Shorebird Watching, Earliest Sunset, Cross-Country Skiers, and Toyon
Shorebird-Watching enters its most agreeable season this month, with migrant and resident birds sharing common winter grounds. Egrets, herons, terns, and a variety of other species provide endless entertainment as they go about the business of fishing and feeding in …
Rainbow Season, Fremont Cottonwoods, Venus & Jupiter, the Moon's Chesire Cat Smile
"Rainbow season" arrives with the first rains of late fall. Scattered showers are best for rainbow watching: sunlight refracting and reflecting through the raindrops causes two bows to appear: an intense circular arc at 42˚, and a bigger, but weaker …
Atmosphereic Ice Crystals, Liquidambar Trees, and Sycamores
Atmospheric ice-crystal effects are often observed, starting about this time of year, because of the frequent appearance of high clouds made of tiny bits of ice. The most familiar of these optical effects is the 22˚-radius halo, or ring, around …
Temperature Inversions, Tides, Sunrise/Sunset, and the Leonid Meteor Shower
Low-lying temperature inversions commonly occur in San Diego as winter approaches. During the night and morning hours, a meterological condition often occurs in which the normal higher-you-go-the colder-it-gets trend is reversed. At such times cold marine air lies below a …
Santa Anas, Monarchs, and Acorns
Santa Ana winds in San Diego County often reach their greatest intensity during November, particularly at the mountain passes, where dry air from a high-pressure area over the interior deserts swoops coastward toward a low-pressure area offshore. The subsiding air …
A Waxing Moon for Halloween -- Just Before Daylight Savings Time Ends
Daylight Savings Time ends this Sunday morning, November 2 at 2 a.m. With the resumption of standard time, midday (the time when the sun reaches its maximum altitude in the south part of the sky) will again be close to …
Temps, Tarantulas, and Turning Leaves
Local air temperatures should be declining most rapidly during this time of year, according to more than a century of local meteorological records. With every successive week, daily maximum temperatures are declining by about 3/4°F, and daily minimum temperatures are …
Black Oaks, Floss Silks, and Orionid
The tawny hues of the black oak tree, the floss silk tree, and the Orionid meteor show
The tawny hues of the black oak tree are just beginning to highlight the slopes of San Diego County's higher mountains. Named for the dark coloring of its bark, especially when wet, the black oak (Quercus kelloggii) is the only …
October's Beach Sand, Low Tides, Full Moon, and Venus
As the beach-going season winds down, San Diego County's coastline is padded by what is likely the deepest and widest accumulations of sand we'll see this year. Many stretches of the coastline are vulnerable to powerful waves associated with winter …
Dense Ground Fogs, Spider Webs, Chinese Flame Trees, and a Thin Crescent Moon
Dense Ground Fogs, Spider Webs, Chinese Flame Trees, and a Thin Crescent Moon
Dense ground fogs are a trademark of the onset of autumn along San Diego's coastal strip. Fog materializes during the night and early morning hours when moist marine air that has settled in valleys and low areas is chilled below …
Return of the Santa Anas
Santa Anas, Hot and Smoggy Days, Zodiacal Light
Late September 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 percent of the …
Fall Officially Begins
Fall officially begins at 8:44 a.m. Pacific Daylight Time on Monday, September 22 -- a good excuse to throw a "thank-God-it's-Monday-morning" party to celebrate the occasion and kick off the work week. At equinox, the sun shines directly down somewhere …
Earlier Sunsets, Coastal Sage, and a Harvest Moon
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 …