• This week's San Luis Obispo Tribune's Weather Watch Column “Powerful king tides are coming to Central Coast beaches. This is why." 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 Monday 11/23/20 ========== SEA/SWELL: A 6- to 8-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- to 15-second period) is forecast along our coastline this afternoon through tonight. A 5- to 7-foot northwesterly (300-degree, deep-water) swell (with an 8- to 14-second period) is forecast along our coastline on Tuesday into Wednesday morning. A 9- to 11-foot northwesterly (315-degree, deep-water) sea and swell (with a 7- to 20-second period) will arrive Wednesday afternoon, increasing to 11- to 13-feet (with a 16- to 18-second period) on Wednesday night through Thursday morning. This northwesterly sea and swell will decrease to 8 to 10 feet (with a 15- to 17-second period) on Thursday afternoon and night, further lowering to 6 to 8 feet by Friday morning. A 4- to 6-foot northwesterly (305-degree, deep-water) swell (with an 8- to 15-second period) is forecast along our coastline on Friday afternoon through next Monday. ATMOSPHERIC CONDITIONS: Last week saw rain, this week it will be dry with crisp autumn nights and mornings with mild afternoons. An upper-level trough of low-pressure will move through the Central Coast today. This system will produce strong to gale-force (25 to 38 mph) northwesterly winds, a few areas of marine low clouds along the northwesterly facing beaches and cooler temperatures, but no rain. Today's high temperatures will reach the mid-60s throughout the Central Coast. The Santa Lucia winds will return on Tuesday with clear skies as high pressure quickly rebuilds over Central California. A dry cold front will produce strong to gale-force (25 to 38 mph) northwesterly winds, variable low to mid-level clouds, increasing sea and swell, and cooler temperatures on Wednesday. Gusty Santa Lucia (northeasterly) winds will return on Thanksgiving Day through Sunday. These winds will produce mostly clear conditions with cold (subfreezing) mornings in the inland valleys and mild afternoons throughout San Luis Obispo and Santa Barbara counties as high pressure builds back in the wake of the departing low-pressure system. Initialized with multiple atmospheric and oceanic variables, the ensemble packages that typically produce a broad range of possible weather outcomes indicate dry conditions through the first week of December. 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 Inland Valleys, and medium (R2) to high (R3) levels in the Far Inland Areas today. The PG&E Fire Index Ratings will be at medium (R2) levels throughout our area; however, FIA 510 (Coastal Valley) will be at a high (R4) levels on Tuesday. The PG&E Fire Index Ratings will be at high (R3) levels throughout our area; however, FIA 510 (Coastal Valley) will be at a very high (R5) levels on Wednesday. DIABLO CANYON METEOROLOGICAL TOWER TEMPERATURE DATA: Yesterday's Today's Tomorrow's Min Max Min Max Min Max 52.0° 61.6° 53.0° 62.0° 54.0° 67.0° PG&E Weather Office in San Francisco predicted temperatures for San Luis Obispo County Inland Temperatures, Paso Robles Actual Predicted Sun Mon Tue Wed Thu Fri Sat Sun Mon 32 70 33 65 34 66 35 61 34 60 29 65 29 66 30 68 29 68 Coastal Valleys Temperatures, San Luis Obispo Sun Mon Tue Wed Thu Fri Sat Sun Mon 40 72 46 66 43 70 41 66 42 67 37 74 38 73 39 73 39 74 WINDS: Strong to gale-force (25 to 38 mph) northwesterly winds are forecast this afternoon, decreasing tonight. Moderate to fresh (13 to 24 mph) Santa Lucia (northeasterly) winds are forecast on Tuesday. Strong to gale-force (25 to 38 mph) northwesterly winds are forecast on Wednesday. The Santa Lucia winds will return on Thursday through Sunday. DIABLO CANYON METEOROLOGICAL TOWER WIND DATA: Today's Maximum Winds: Max peak winds: NE 31.0 mph @ 8:00 a.m. Max sustained wind: NE 23.0 mph @ 8:00 a.m. Monday's Maximum Winds: Max peak winds: NW 36.0 mph @ 4:30 p.m. Max sustained wind: NW 30.0 mph @ 4:30 p.m. SEAWATER TEMPERATURES: Seawater temperatures will range between 53 and 56 degrees through Sunday. OCEAN CURRENTS: A southerly (offshore) flowing current is expected to flow southward through Sunday. SEAWATER VISIBILITY: Seawater visibility was available today. ========================================================================== 24-Hour Ocean Condition Outlook for Monday 11/23 to Tuesday 11/24 SEA/SWELL: DIR. NW HT. 4-6 PER. 7-9 This morning Increasing to: DIR. NW HT. 6-8 PER. 5-15 This afternoon Remaining at: DIR. NW HT. 6-8 PER. 6-15 Tonight WINDS: DIR. NE SPEED 20-25 + 30 This morning Increasing to: DIR. NW SPEED 25-30 + 40 This afternoon Decreasing to: DIR. NW SPEED 15-20 Tonight ========================================================================== 48-Hour Ocean Condition Outlook for Tuesday 11/24 to Wednesday 11/25 SWELL: DIR. NW HT. 5-7 PER. 7-15 Tuesday morning Remaining at: DIR. NW HT. 5-7 PER. 8-14 Tuesday afternoon Remaining at: DIR. NW HT. 5-7 PER. 8-14 Tuesday night WINDS: DIR. NE SPEED 10-15 + 20 Tuesday morning Decreasing to: DIR. NW SPEED 10-15 Tuesday afternoon Decreasing to: DIR. NW SPEED 5-10 Tuesday night ========================================================================== Extended Ocean Condition Outlook: Strong to gale-force (25 to 38 mph) northwesterly winds are forecast on Wednesday. ========================================================================== The 24 - Hour Ocean Data from the Diablo Canyon Waverider Buoy: MONTH DAY TIME SIG.HEIGHT PERIOD SWELL DIRECTION SST 11 20 1100 5.9 11 279 54.1 11 21 0130 4.7 15 257 53.6 11 22 2200 5.5 8 282 53.8 11 23 0400 5.1 8 279 54.7 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 -------------------------------------------------------------------------- 11 20 1100 180 11 3 50 15 52 148 687 459 219 11 21 0130 142 7 2 64 152 66 260 217 279 229 11 22 2200 169 7 1 2 4 26 60 118 423 469 11 23 0400 143 7 1 3 8 13 58 58 326 376 Daily Swell Inspection Program for today: NAME DAY TIME HEIGHT PERIOD SST (PDT) (FEET) (SECONDS) (DEG. F) # 66 Ocean Station Papa 23 0430 20 13 50.0 # 06 SE Papa 23 0430 12 14 62.8 # 05 West Washington State 23 0420 12 12 55.9 # 59 California 23 0450 10 14 59.9 # 36 Grays Harbor 23 0400 8 13 50.5 # 44 Humboldt Bay Waverider 23 0408 9 13 51.8 # 94 Cape Mendocino 23 0432 9 14 51.6 # 29 Point Reyes Waverider 23 0403 8 15 54.5 # 42 San Francisco Sandbar 23 0430 5 14 54.3 # 15 Monterey Waverider Buoy 23 0400 5 14 53.6 # 28 Cape San Martin 23 0440 6 15 n/a # 76 DCPP Waverider 23 0400 5 8 54.7 # 22 Santa Lucia Escarpment 23 0400 8 7 56.8 # 11 Point Arguello 23 0440 7 7 56.1 # 63 Harvest Buoy 23 0430 9 8 55.9 # 19 San Nicolas Island 23 0430 9 8 59.2 # 20 Scripps 23 0422 3 7 60.6 # 10 Waimea Bay, Hawaii 23 0400 7 9 80.1 # 33 Pearl Harbor Entrance 23 0400 4 8 79.3 # 04 SE Hawaii 23 0400 10 10 79.0 Precipitation at the Diablo Canyon Ocean Lab: Saturday 1500 through Sunday 1500 0.00 inches Sunday 1500 through Monday 1500 0.00 inches Precipitation this rain season (July 1 - June 30): 0.62 inches Average season rainfall at DCPP to date: 1.50 inches Ocean Lab Barometer: 29.96 in/Hg or 1014.6 0.0 mb (steady) Today's Sunrise 6:46 AM Sunset 4:53 PM Tomorrow's Sunrise 6:47 AM Sunset 4:53 PM Tides: Low Tide High Tide AM PM AM PM 23 Monday 11:59 2.2 11:41 0.7 5:59 4.7 5:16 3.9 24 Tuesday ----- --- 12:50 1.6 6:31 4.9 6:22 3.8 25 Wednesday 12:20 1.0 1:31 1.1 6:58 5.1 7:18 3.8 26 Thursday 12:53 1.4 2:07 0.7 7:22 5.3 8:08 3.8 27 Friday 1:23 1.7 2:41 0.3 7:44 5.5 8:53 3.7 28 Saturday 1:50 2.0 3:13 0.0 8:07 5.6 9:36 3.7 29 Sunday 2:18 2.2 3:46 -0.3 8:32 5.7 10:20 3.7 30 Monday 2:46 2.4 4:21 -0.4 8:58 5.8 11:04 3.7 1 Tuesday 3:15 2.7 4:58 -0.5 9:27 5.8 11:52 3.6 2 Wednesday 3:47 2.9 5:38 -0.5 9:59 5.7 ----- --- 3 Thursday 4:24 3.0 6:22 -0.4 10:35 5.6 (12:46 3.6) 4 Friday 5:10 3.2 7:10 -0.3 11:16 5.3 (1:45 3.6) 5 Saturday 6:16 3.3 8:01 -0.2 2:46 3.7 12:07 5.0 6 Sunday 7:49 3.3 8:54 0.0 3:38 3.9 1:11 4.6 7 Monday 9:29 3.0 9:46 0.2 4:21 4.3 2:33 4.2 8 Tuesday 10:52 2.3 10:37 0.5 4:58 4.7 4:04 3.9 ======================================================================== This day in weather history 1943 - Northern New Hampshire was in the grips of a record snowstorm which left a total of 55 inches at Berlin, and 56 inches at Randolph. The 56 inch total at Randolph established a 24-hour snowfall record for the state. In Maine, Middle Dam received a record 35 inches of snow in 24 hours. (David Ludlum) 1988 - Low pressure crossing the Great Basin brought wintry weather to parts of the western U.S. Up to a foot of snow blanketed Yellowstone Park and winds gusted to 70 mph at Casper WY and reached 95 mph near Reno NV. Up to seven inches of rain was reported in the Grass Valley and Nevada City area of California. Paradise CA was soaked with 5.37 inches of rain in 24 hours. (The National Weather Summary) (Storm Data) 2014 - A strong 1,033 millibar transitory area of high pressure will move over the Great Basin today into Wednesday. This condition will produce fresh to strong (19- to 31-mph) Santa Lucia (offshore) winds during the night and morning hours into Wednesday morning. 2015 - On Saturday and Sunday, the Santa Lucia (northeasterly) winds helped to create near record-breaking high temperatures throughout the coastal regions of San Luis Obispo and northern Santa Barbara counties with plenty of mid- to high-80s temperature readings. 2017 - For the second day in a row, Paso Robles and San Luis Obispo broke heat records and Santa Maria tied a record. San Luis Obispo hit 91 degrees Wednesday, surpassing the old record of 87 degrees in 2002. The high in Paso Robles was 88 degrees, smashing the old record by nine degrees of 79 set in 2015. Santa Maria tied its 1933 record of 89 degrees. 2019 - Over the last 12-hours, a weak cold front has produced light rain showers throughout the Central Coast. So far, Cambria has seen the most with 0.51 of an inch of rain, while Los Osos has recorded 0.33 of an inch. Further south, Arroyo Grande has only seen a few hundreds of an inch of rain. ======================================================================== 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 PGEweather@pge.com. Any questions about this forecast, please E-mail John Lindsey at jcl5@pge.com