• This week's San Luis Obispo Tribune's Weather Watch Column “Do great white sharks benefit from climate change? Ask ‘mother of sharks’ scientist" www.sanluisobispo.com/news/weather/weather-watch/ • You can catch live weather forecasts weekday mornings from 6-9 a.m. on KVEC 920 AM on First Look with Andy Morris. • For weather updates, charts and photos, along with power outage information and other events you can follow me at: https://twitter.com/pge_john ========== PG&E DCPP Weather Forecast for Friday 10/15/21 ========== SEA/SWELL: Today's 4- to 6-foot northwesterly (290-degree, deep-water) swell (with an 8- to 14-second period) will lower to 3- to 5- feet with the same period on Saturday through Sunday. Gale-force northwesterly winds off the Central California coastline will generate a 5- to-7-foot northwesterly (310- degree, deep-water) sea and swell (with a 5- to 13-second period) on Monday, decreasing to 4- to 6-feet (with a 7- to 13-second period) on Tuesday through Thursday. Arriving from the Southern Hemisphere: Today's 1- to 2-foot Southern Hemisphere (210-degree, deep- water) swell (with a 14- to 16-period) will continue through Sunday. ATMOSPHERIC CONDITIONS A 584 dm upper-level high centered over Central California will produce moderate to fresh (13 to 24 mph with gusts to 30 mph) Santa Lucia (northeasterly) winds, clear skies and warm temperatures through Saturday morning. Today’s high temperature will reach the mid-80s in the inland valleys (Paso Robles) and the coastal valleys (San Luis Obispo). The beaches will range between the mid- to high-70s. Gentle to moderate southwesterly to northwesterly (onshore) winds will develop on Saturday afternoon through Sunday as high pressure over the Central California weakens. This condition will produce gentle to moderate (8 to 18 mph) southwesterly to northwesterly (onshore) winds on Saturday afternoon through Sunday which allow the marine layer to redevelop along the coastline with areas of fog and mist during the night and morning. A cold front will move southward along the California coastline and bring rain as far south as Monterey on Sunday. This front will wash out over the Central Coast Sunday night with pockets of drizzle. A pattern of fresh to strong (19 to 31 mph) northwesterly winds developing during the afternoon, decreasing during the night and morning is forecast on Monday through Thursday. Over this period, areas of fog and mist is expected during the night and morning, becoming mostly clear and sunny during the late morning and afternoon with mild temperatures. The longer-range models and charts are advertising unsettled weather developing along the Central Coast next weekend. WILDFIRE INDEX RATINGS: COASTAL: FIA 508 INLAND: FIA 497, 510, 575, 580, 582 and 590 The PG&E Fire Index Ratings will be at high (R3) levels along the Coastline and Coastal Valleys and very high (R4) levels in the Inland Valleys, and the Far Inland areas today. The PG&E Fire Index Ratings will be at high (R3) levels along the Coastline and very high (R4) levels in the Coastal and Inland Valleys, and the Far Inland areas on Saturday. The PG&E Fire Index Ratings will be at high (R3) levels along the Coastline and Coastal Valleys and very high (R4) levels in the Inland Valleys, and the Far Inland areas on Sunday. DIABLO CANYON METEOROLOGICAL TOWER TEMPERATURE DATA: Yesterday's Today's Tomorrow's Min Max Min Max Min Max 49.2° 73.2° 59.5° 75.0° 56.0° 74.0° PG&E Weather Office predicted temperatures for San Luis Obispo County Inland Temperatures, Paso Robles (Actual) Predicted (Thu) Fri Sat Sun Mon Tue Wed Thu (40 80) 42 86 42 89 43 77 44 73 39 73 41 76 44 81 Coastal Valleys Temperatures, San Luis Obispo (Thu) Fri Sat Sun Mon Tue Wed Thu (47 82) 51 87 47 85 48 71 47 70 43 69 45 72 48 77 WINDS: A pattern of moderate to fresh (13 to 24 mph with gusts to 30 mph) Santa Lucia (northeasterly) winds developing during the night and morning, shifting out of the northwest and decreasing during the afternoon will continue through Saturday morning. Gentle to moderate (8 to 18 mph) southwesterly to northwesterly (onshore) winds are forecast on Saturday through Sunday. A pattern of fresh to strong (19 to 31 mph) northwesterly winds developing during the afternoon, decreasing during the night and morning is forecast on Monday through Thursday. DIABLO CANYON METEOROLOGICAL TOWER WIND DATA: Today's Maximum Winds: Max peak winds: NE 23.0 mph @ 0:30 a.m. Max sustained wind: NE 17.0 mph @ 0:30 a.m. Yesterday's Maximum Winds: Max peak winds: NW 30.0 mph @ 2:30 p.m. Max sustained wind: NW 22.0 mph @ 2:30 p.m. SEAWATER TEMPERATURES: Seawater temperatures will range between 52 and 54 degrees through Tuesday. OCEAN CURRENTS: Today's southerly (offshore) flowing current will continue to flow southward through Tuesday. SEAWATER VISIBILITY: Seawater visibility was 9 and 11 feet at the Diablo Canyon Marina. ========================================================================== 24-Hour Ocean Condition Outlook for Friday 10/15 to Saturday 10/16 SWELL: DIR. NW HT. 4-6 PER. 8-14 This morning Remaining at: DIR. NW HT. 4-6 PER. 8-14 This afternoon Remaining at: DIR. NW HT. 4-6 PER. 8-14 Tonight (Combined with: DIR S HT. 1-2 PER. 14-16 All day) WINDS: DIR. NE SPEED 15-25 + 30 This morning Decreasing to: DIR. NW SPEED 15-20 This afternoon Decreasing to: DIR. NE SPEED 10-15 Tonight ========================================================================== 48-Hour Ocean Condition Outlook for Saturday 10/16 to Sunday 10/17 SWELL: DIR. NW HT. 3-5 PER. 8-14 Saturday morning Remaining at: DIR. NW HT. 3-5 PER. 8-14 Saturday afternoon Remaining at: DIR. NW HT. 3-5 PER. 8-14 Saturday night (Combined with: DIR S HT. 1-2 PER. 14-16 All day Saturday) WINDS: DIR. NE SPEED 15-25 + 30 Saturday morning Decreasing to: DIR. NW SPEED 15-20 Saturday afternoon Decreasing to: DIR. NE SPEED 10-15 Saturday night ========================================================================== Extended Ocean Condition Outlook: A pattern of fresh to strong (19 to 31 mph) northwesterly winds developing during the afternoon, decreasing during the night and morning is forecast on Monday through Thursday. ========================================================================== The 24 - Hour Ocean Data from the Diablo Canyon Waverider Buoy: MONTH DAY TIME SIG.HEIGHT PERIOD SWELL DIRECTION SST 10 07 1300 5.3 20 273 59.5 10 08 2000 5.7 7 291 60.1 10 09 0000 4.6 17 245 57.4 10 10 1930 5.4 8 277 59.4 10 11 1600 10.8 11 280 56.5 10 12 0430 9.2 12 275 53.4 10 13 0100 7.1 10 294 52.5 10 14 1700 7.2 10 287 54.9 10 15 0700 5.2 15 242 52.7 DCPP Ocean Lab Waverider Buoy Energy Spectral Analysis: Mo. daytime sig.ht. sig.per. energy (cm.sq.) (cm) (sec) 22+ 20 17 15 13 11 9 7 -------------------------------------------------------------------------- 10 07 1300 161 9 5 158 29 59 84 278 406 265 10 08 2000 174 7 2 6 62 125 43 88 227 577 10 09 0000 139 7 2 8 82 84 47 30 133 395 10 10 1930 164 7 3 42 19 26 37 94 436 444 10 11 1600 329 11 6 40 40 54 433 2288 1646 1150 10 12 0430 281 11 3 24 137 116 617 1320 1126 819 10 13 0100 215 9 3 24 88 243 334 564 785 428 10 14 1700 220 9 1 5 69 119 140 931 1258 352 10 15 0700 159 9 1 4 23 298 293 218 314 237 Daily Swell Inspection Program for today: NAME DAY TIME HEIGHT PERIOD SST (PDT) (FEET) (SECONDS) (DEG. F) # 66 Ocean Station Papa 15 0700 8 13 48.4 # 06 SE Papa 15 0750 9 14 n/a # 05 West Washington State 15 0750 11 15 57.9 # 59 California No Recent Report # 36 Grays Harbor 15 0700 9 12 54.9 # 44 Humboldt Bay Waverider 15 0708 10 13 52.0 # 94 Cape Mendocino 15 0710 8 9 50.9 # 29 Point Reyes Waverider 15 0700 9 13 52.3 # 42 San Francisco Sandbar 15 0730 6 13 57.0 # 15 Monterey Waverider Buoy 15 0730 9 14 57.7 # 57 Point Sur 15 0700 9 13 56.7 # 28 Cape San Martin 15 0750 8 13 57.9 # 76 DCPP Waverider 15 0730 5 15 52.7 # 22 Santa Lucia Escarpment 15 0700 9 13 57.2 # 11 Point Arguello 15 0750 9 14 n/a # 63 Harvest Buoy 15 0730 9 13 54.9 # 19 San Nicolas Island 15 0730 7 14 62.4 # 20 Scripps 15 0700 2 10 63.3 # 10 Waimea Bay, Hawaii 15 0731 5 10 78.3 # 33 Pearl Harbor Entrance 15 0700 4 8 79.2 # 04 SE Hawaii 15 0700 8 10 78.3 Precipitation at the Diablo Canyon Ocean Lab Wednesday 1500 through Thursday 1500 0.00 inches Thursday 1500 through Friday 1500 0.00 inches Precipitation this rain season (July 1 - June 30): 0.07 inches Average season rainfall at DCPP to date: 0.70 inches Ocean Lab Barometer: 1018.4 mb or 30.08 in/Hg 0.0 mb (steady) Today's Sunrise 7:10 AM Sunset 6:28 PM Tomorrow's Sunrise 7:10 AM Sunset 6:26 PM Tides: Low Tide High Tide AM PM AM PM 15 Friday 1:11 -0.2 1:25 2.3 8:05 4.6 7:06 5.1 16 Saturday 1:58 -0.1 2:17 1.8 8:37 4.9 8:04 5.1 17 Sunday 2:38 0.1 3:01 1.3 9:06 5.1 8:54 5.0 18 Monday 3:12 0.4 3:41 0.9 9:32 5.2 9:40 4.8 19 Tuesday 3:41 0.8 4:19 0.6 9:57 5.4 10:24 4.6 20 Wednesday 4:08 1.2 4:55 0.4 10:20 5.4 11:07 4.3 21 Thursday 4:34 1.7 5:31 0.2 10:42 5.5 11:51 4.1 22 Friday 4:58 2.1 6:09 0.2 11:05 5.4 ----- --- 23 Saturday 5:22 2.5 6:50 0.3 11:30 5.3 (12:40 3.8) 24 Sunday 5:46 2.8 7:37 0.4 11:57 5.2 (1:38 3.6) 25 Monday 6:12 3.2 8:32 0.5 2:54 3.5 12:29 4.9 26 Tuesday 6:44 3.4 9:38 0.6 4:43 3.5 1:12 4.7 27 Wednesday ---- --- 10:45 0.5 ---- --- 2:15 4.4 28 Thursday 10:39 3.5 11:44 0.5 6:57 3.8 3:43 4.3 29 Friday ----- --- 12:02 3.2 7:18 4.0 5:08 4.3 30 Saturday 12:31 0.4 12:56 2.6 7:38 4.3 6:18 4.4 31 Sunday 1:12 0.3 1:41 2.0 7:58 4.6 7:18 4.6 1 Monday 1:47 0.4 2:23 1.3 8:20 5.0 8:13 4.7 2 Tuesday 2:22 0.5 3:06 0.6 8:45 5.5 9:06 4.7 3 Wednesday 2:56 0.8 3:50 -0.1 9:13 5.9 10:00 4.6 4 Thursday 3:30 1.2 4:36 -0.7 9:45 6.3 10:55 4.5 5 Friday 4:06 1.6 5:25 -1.0 10:20 6.5 11:55 4.3 6 Saturday 4:45 2.0 6:18 -1.2 10:59 6.6 ----- --- Daylight Saving Time ends on Sunday, November 7, 2021, at 2:00 a.m. On Saturday night, clocks are set back one hour to “fall back.” 7 Sunday 4:28 2.5 6:15 -1.1 1:00 4.0 10:42 6.5 8 Monday 5:19 2.9 7:18 -0.9 1:14 3.9 11:33 6.1 9 Tuesday 6:27 3.2 8:26 -0.7 2:38 3.9 12:32 5.7 10 Wednesday 8:04 3.3 9:34 -0.4 3:58 4.0 1:47 5.1 11 Thursday 9:52 3.0 10:37 -0.2 5:00 4.3 3:14 4.7 12 Friday 11:18 2.5 11:31 0.1 5:47 4.6 4:39 4.5 ========================================================================= This day in weather history 2014 - Seawater temperatures ranged from 62 and 66 degrees along the Pecho Coast. 2016 - Since Friday night, orographic enhancement has produced much greater amounts of rain in the coastal hills than in other Central Coast locations. Dawn at the Walter Ranch in the hills above Cambria reported 1.80 inches or rain. Jeanette at San Luis Bay Estates above Avila Beach reported 0.83 of an inch. Warren had 0.92 of an inch, while Terry recorded 0.73 of an inch in the hills near Nipomo. Calvin from Adelaide reported 0.75 of an inch. Most other locations in the coastal and inland valleys have reported between 0.05 and 0.25 of an inch of rain. 2020 - Lompoc hit 100 degrees yesterday, breaking the old record of 96° recorded on October 14, 1961. The high temp of 102° at the Santa Maria Airport bested the old record set in 1961. Cal Poly hit 102 degrees, breaking its record of 101 back in 1961. The temperature in Los Osos dropped from 92 degrees at noon yesterday to 68 degrees in just one hour as the northwesterly (onshore) winds kicked in and brought cool and moist air from the Pacific to coastal regions. ======================================================================== This weather forecast is a service provided by Pacific Gas and Electric Company (PG&E) to our energy customers. The forecast is valid only for the Diablo Canyon Power Plant coastline area (approximately a one-half mile radius surrounding the plant). Some of the information in this forecast is provided by Pacific Weather Analysis, with their permission. Replication of this email must be in its entirety. You may view and copy material from this forecast, provided you retain all copyright, trademark, and other proprietary notices displayed on the materials. Use of these materials in publications, radio, television, other media presentations, or other websites is prohibited without PG&E's express written consent. PG&E is a subsidiary of PG&E Corporation, one of the largest natural gas and electric utilities in the United States, delivering some of the nation's cleanest energy to 15 million people in Northern and Central California. If you would like to subscribe or unsubscribe to this daily forecast, please send an email to mailto:PGEweather@pge.com. Any questions about this forecast, please E-mail John Lindsey at mailto:jcl5@pge.com