Entries
Venus, Tides, and December Hikes
The Planet Venus blazes like a beacon high in the eastern sky during the early stages of morning twilight in late November through December. On very clear mornings, Venus can even be spotted with the naked eye following sunrise, assuming …
Tarantulas and Ice Crystals
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 …
Rainbow Season
"Rainbow Season" arrives with the first rains of the season. 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 …
Beaver Moon Tonight
November's Full Moon rises dramatically in the east at around 4:45 p.m., just after the time of sunset, on Sunday, November 21. Barring the incursion of overnight low clouds across the coastal strip, San Diegans can witness the same full …
Temperatures, Sunsets, and Fremont Cottonwoods
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 …
The Annual Leonid Meteor Shower
The Annual Leonid Meteor Shower, famous for its outbursts over the period 1998-2002, has now settled down to a modest display of only about 10-30 visible events per hour (as seen under clear, dark skies). This year the shower peaks …
Declining Temps, Santa Anas, and Acorn Dropping
Local 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°Fahrenheit, and daily minimum temperatures are plummeting …
Daylight Savings Time Arrives
Daylight Savings Time ends this Sunday morning, November 7 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 …
New Moon = Extreme Tides
Extreme Low and High Tides are taking place this weekend, in concert with the new moon. On Friday, November 5, the tide crests at +6.7 feet at 8:39 a.m., and then falls to a low of -1.1 feet at 3:28 …
The Taurid Meteor Shower and the Planet Venus
The Taurid Meteor Shower, featuring about 10-15 visible events per hour -- as seen under clear, dark skies -- peaks this year on the morning of Thursday, November 4. Best times for viewing are approximately 10pm to 3am. No moonlight …
Floss Silks, Black Oaks, and Autumn Leaves
The Floss Silk Tree, a conspicuous "autumn bloomer" here and there around San Diego, has been showing off its pinkish or purplish, hibiscus-like flowers for at least a month now. The broad, heavy trunks of this South American import, studded …
Blood Moon Tonight
The Full Moon rises majestically in the east at around 5:50pm on Friday, October 22, some 15 minutes before the time of sunset. If the skies are clear, this is a perfect time to take a late afternoon walk and …
The Orionid Meteor Shower
One of the year's five best annual showers, the Orionid Meteor Shower, peaks on the morning of Thursday, October 21. Unfortunately, the nearly full moon's glare will hamper observations of the meteors all night long. Despite the moon glare, and …
Ground Fog, Spider Webs, and Chinese Flame Trees
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 …
Low Tides, a Waxing Crescent Moon, and Jupiter's Satellites
October's Lowest Tides, coinciding with afternoon hours several days in a row, usher in several months of excellent tidepooling opportunities. A -0.6 foot tide occurs at 3:34pm on the Thursday, October 7. A -0.8 foot tide occurs at 4:20pm on …
Smog, Fall Migrant Birds, and Coastal Sage
The Smoggiest Days of the Year are most likely to occur during the next several weeks. Persistent temperature inversions (warmer air overlying cool marine air) are frequent this time of year. These inversions conspire with the mountainous topography of East …
The Santa Anas Come to San Diego
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 8:09pm local time on Wednesday, September 22 -- a good excuse to throw an impromptu evening party to celebrate the occasion. At equinox, the sun shines directly down somewhere on Earth's equator. At 8:09pm San Diego …
Jupiter at Opposition Today
Jupiter, the brilliant, star-like object glowing like a beacon in the eastern sky after nightfall, comes to "opposition" (180° away from the sun) on Monday, September 20. Rising at sunset and setting at sunrise, the giant planet is as close …
Sunsets and Thundershowers
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 …