Weather forecast for week of Dec. 20 — Chilly mornings, windy and dry until Christmas
Monday is the first day of winter as the hiemal solstice occurs at 2:02 a.m. PST. Unfortunately, it will not seem like the season as dry conditions will continue through Christmas. A once-in-a-lifetime event will happen on the first full night of winter (Monday night) with the conjunction of Jupiter and Saturn that will appear as a single “star”. The two planets will appear low in the southwest in the hour after sunset.
Strong to gale-force (25 to 38 mph) Santa Lucia (northeasterly) winds are forecast Sunday morning, decreasing to moderate to fresh (13 to 24 mph) levels on Sunday afternoon through Monday morning. These offshore winds will produce mostly clear and dry conditions with chilly mornings and mild afternoons. However, dense ground fog is expected to develop in the inland and a few of the coastal valleys during the late-night and morning. Tule fog will also develop across the San Joaquin Valley.
Gentle to moderate (8 to 18 mph) northwesterly winds are forecast on Monday afternoon through Tuesday morning. These onshore winds will allow the marine layer with areas of fog and mist to develop in the coastal regions by Tuesday morning.
Strong to gale-force (25 to 38 mph) northwesterly winds are expected Tuesday afternoon, decreasing and shifting out of the northeast by Tuesday night into Wednesday, producing mostly clear skies.
An upper-level low-pressure system is expected to develop about 400 miles to the southwest of Los Angeles on Thursday and remain nearly stationary through Christmas. This system will produce gentle southerly winds, partly cloudy skies, and marine stratus with areas of fog and mist. The cloudy conditions will result in milder overnight temperatures and cooler daytime highs.
The longer-range models hint at a possible pattern shift the week after Christmas with a chance for wet weather as the storm track could drop southward during the final week of the year.
Surf Report
Sunday’s 6- to 8-foot northwesterly (300-degree, deep-water) swell (with an 8- to 14-second period) will decrease to 5- to 7-feet along our coastline on Monday.
Increasing northwesterly winds off the California coastline will generate a 5- to 7-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- to 15-second period) on Tuesday through Wednesday, decreasing to 3 to 5 feet on Thursday through Friday. Another long-period northwesterly swell is expected to arrive on Christmas.
Seawater temperatures will range between 53 and 55 degrees through Saturday.
This week’s temperatures
LOWS AND HIGHS, PASO ROBLES
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
28, 67 | 28, 71 | 31, 65 | 31, 64 | 30, 65 | 29, 66 | 33, 65 | 37, 63 |
LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
41, 76 | 40, 74 | 41, 70 | 40, 67 | 36, 69 | 38, 69 | 42, 68 | 45, 65 |
PG&E safety tip
PG&E Safety Message: Driving in the fog can be hazardous. According to the California Highway Patrol, here are some tips for driving in foggy conditions: ▪ Drive with lights on low beam. High beams will reflect off the fog, creating a “white wall” effect. ▪ Reduce your speed,and watch your speedometer. Fog creates a visual illusion of slow motion when you might actually be speeding.
John Lindsey is PG&E’s Diablo Canyon marine meteorologist and a media relations representative. Email him at pgeweather@pge.com or follow him on Twitter @PGE_John.