SLO County forecast for week of Sept. 20: Seasonal weather with better air quality
Unlike last week which saw heavy smoke and haze from the numerous wildfires burning across the state, this week is expected to see much better air quality as more seasonable weather returns.
The northwesterly winds will decrease, and the marine layer will redevelop along the coastline and deepen and move inland during the overnight hours on Sunday into Tuesday as a weak low-pressure system moves through the Central Coast.
This condition will produce night and morning mist and fog along with mild temperatures. Daytime high temperatures will range from the 60s along the coast, 70s for the coastal valleys (San Luis Obispo), and upper 80s in the inland valleys (Paso Robles).
Slight warming is then expected to follow over the latter half of the week, although only a couple of degrees difference is currently forecasted.
Attention then turns to the last weekend of the month, where long-range models hint at a breezy Santa Lucia (northeasterly) wind event next weekend into early the following week.
Details remain extremely unclear at this time; conditions will be monitored closely for any changes. Any offshore wind event will likely bring enhanced fire weather concerns.
Models favor above-average seasonal temperatures into early October following the potential wind event.
Surf report
Strong to gale-force (25 to 38 mph) northwesterly winds along the coastline will generate a 3- to 5-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- to 11-second period) today through Sunday.
A 3- to 4-foot northwesterly (295-degree, deep-water) swell (with an 8- to 11-second period) is expected to develop along our coastline on Monday.
Fresh to strong (19 to 31 mph) northwesterly winds along the coastline will generate a 3- to 5-foot northwesterly (305-degree, deep-water) sea and swell (with a 5- to 8-second period) on Tuesday through Wednesday.
A Gulf of Alaska storm will generate a 6- to 8-foot northwesterly (300-degree, deep-water) sea and swell (with a 6- to 18-second period) on Thursday, peaking at 8 to 10 feet (with a 7- to 17-second period Friday.
Arriving from the Southern Hemisphere: A 1- to 2-foot Southern Hemisphere (215-degree, deep-water) swell (with a 20- to 22-second period) will arrive along our coastline on Sunday, increasing to 1- to 3-feet (with an 18- to 20-second period) on Monday through Tuesday.
Seawater temperatures will range between 57 and 60 degrees through Friday.
This week’s temperatures
LOWS AND HIGHS, PASO ROBLES
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
51, 89 | 51, 88 | 51, 89 | 51, 93 | 52, 94 | 54, 90 | 51, 93 | 54, 98 |
LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
55, 79 | 54, 75 | 53, 77 | 54, 83 | 55, 83 | 57, 79 | 55, 78 | 58, 90 |
PG&E safety tip
We know losing power is an unwelcome disruption to your life, family and work, so we’ve created preparation tips to keep things as normal as possible during a Public Safety Power Shutoff (PSPS).
We’ll offer support like free Wi-Fi , device charging, bagged ice, ADA-accessible restrooms and hand-washing stations at Community Resource Centers in affected communities once the power has been turned off. For information, please visit www.pge.com
John Lindsey’s 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.
CORRECTION: Incorrect temperatures were input in the printed version of the weather report. It should say, “Daytime high temperatures will range from the 60s along the coast, 70s for the coastal valley (San Luis Obispo), and upper 80s in the inland valleys (Paso Robles).