• This Saturday, August 24, 2019, the County of San Luis Obispo Office of Emergency Services and Pacific Gas & Electric, will be conducting the Annual Early Warning System Siren Test. The sirens will be activated twice this Saturday, to test both the primary and back up activation points. During each of these siren tests, all 131 sirens will be activated simultaneously. The first test will be conducted at noon, with a second test following at 12:30 pm. During these tests, the sirens will sound for three minutes. Although the siren system is tested regularly throughout the year, this annual test is the only time all sirens are sounded simultaneously. No action is required on the part of the public during the tests. • 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 08/23/19 =========== SEA/SWELL: Today's 5- to 7-foot (310-degree, deep-water) swell (with an 8- to 13-second period) will decrease to 4- to 6-feet (with an 8- to 12-second period) on Saturday. This northwesterly swell will further decrease to 3 to 5 feet (with an 8- to 12-second period) on Sunday and will remain at this level through Tuesday. A 2- to 4-foot northwesterly (300-degree, deep-water) swell (with an 8- to 11-second period) is forecast along our coastline on Wednesday through next Friday. Arriving from the Southern Hemisphere: Today's 2- to 3-foot Southern Hemisphere (220-degree, deep- water) swell (with a 16- to 18-second period) will remain at this height, but with a gradually shorter period through Saturday. Note: Tropical Storm Ivo will hug the coast of Mexico and generate significant southerly swell along many Southern California beaches this weekend. However, it's waves will come from a direction of 160 degrees and is too southeast to have much of an impact along the Pecho Coast. ATMOSPHERIC CONDITIONS: Gentle to moderate (8 to 18 mph) south to northwesterly (onshore) winds, a persistent marine layer with fog and mist in the coastal regions and near seasonal temperatures are expected to continue through Sunday. Today's high temperatures will reach 80 degrees in Paso Robles, and 75 degrees in San Luis Obispo. The beaches will range between the mid to high 60s. Fresh to strong (19 to 31 mph) afternoon northwesterly winds on Monday should produce clearing along the coastline. Otherwise next week, moderate to fresh (13 to 24 mph) northwesterly (onshore) winds will compressed the marine layer and produce near seasonal temperatures through the first week of September. WILDFIRE INDEX RATINGS: The PG&E Fire Index Ratings will be at low (R1) to medium levels (R2) along the Coastline and Coastal Valleys and high (R3) to very high (R4) levels in the Inland valleys and Far Inland areas today. The PG&E Fire Index Ratings will be at low (R1) to medium levels (R2) along the Coastline and Coastal Valleys and high (R3) to very high (R4) levels in the Inland valleys and very high (R4) to extremely high (R5) in the Far Inland areas on Saturday. Yesterday's Today's Tomorrow's Min Max Min Max Min Max 57.1° 64.8° 56.4° 65.0° 56.0° 64.0° PG&E Weather Office in San Francisco predicted temperatures for San Luis Obispo County Inland Temperatures, Paso Robles Actual Predicted Thu Fri Sat Sun Mon Tue Wed Thu Fri 59 98 60 80 57 93 57 99 61 97 60 96 58 91 58 92 58 96 Coastal Valleys Temperatures, San Luis Obispo Thu Fri Sat Sun Mon Tue Wed Thu Fri 58 82 59 75 55 76 54 81 55 83 55 81 55 78 57 79 57 82 WINDS: Gentle to moderate (8 to 18 mph) variable winds are forecast through Sunday. Fresh to strong (19 to 31 mph) afternoon northwesterly winds are expected to develop Monday, decreasing to moderate to fresh (13 to 24 mph) levels on Tuesday through Wednesday. DIABLO CANYON METEOROLOGICAL TOWER WIND DATA: Last night's Maximum Winds: Max peak winds: NW 13.0 mph @ 3:30 p.m. Max sustained wind: NW 10.0 mph @ 3:30 p.m. Yesterday's Maximum Winds: Max peak winds: NW 42.0 mph @ 3:00 p.m. Max sustained wind: NW 35.0 mph @ 1:30 p.m. SEAWATER TEMPERATURES: Intake seawater temperatures will range between 56 and 59 degrees through tonight. Intake seawater temperatures will increase to 58 to 62 degrees Saturday through Sunday. OCEAN CURRENTS: Today's northerly (onshore) flowing current will continue through Sunday. SEAWATER VISIBILITY: Seawater visibility was 6 to 8 feet at the Diablo Canyon Marina. ========================================================================== 24-Hour Ocean Condition Outlook for Friday 08/23 to Saturday 08/24 SWELL: DIR. NW HT. 5-7 PER. 8-13 This morning Remaining at: DIR. NW HT. 5-7 PER. 8-13 This afternoon Remaining at: DIR. NW HT. 5-7 PER. 8-13 Tonight (Combined with: DIR. SW HT. 2-3 PER. 16-18 All day) WINDS: DIR. SE SPEED 5-10 This morning Increasing to: DIR. NW SPEED 10-15 This afternoon Decreasing to: DIR. SW SPEED 5-10 Tonight ========================================================================== 48-Hour Ocean Condition Outlook for Saturday 08/24 to Sunday 08/25 SWELL: DIR. NW HT. 4-6 PER. 8-12 Saturday morning Remaining at: DIR. NW HT. 4-6 PER. 8-12 Saturday afternoon Remaining at: DIR. NW HT. 4-6 PER. 8-12 Saturday night (Combined with: DIR. SW HT. 1-3 PER. 14-16 All day Saturday) WINDS: DIR. SE SPEED 5-10 Saturday morning Increasing to: DIR. NW SPEED 10-15 Saturday afternoon Decreasing to: DIR. SW SPEED 5-10 Saturday night ========================================================================== Extended Ocean Condition Outlook: Gentle to moderate (8 to 18 mph) variable winds are expected through Sunday. ========================================================================== The 24 - Hour Ocean Data from the Diablo Canyon Waverider Buoy: MONTH DAY TIME SIG.HEIGHT PERIOD SWELL DIRECTION SST 08 17 2202 5.2 9 297 58.6 08 18 1033 4.3 10 292 57.2 08 19 0933 2.6 14 248 60.1 08 20 2203 3.8 6 290 56.1 08 21 2303 6.0 8 286 57.7 08 22 0403 4.2 20 220 56.3 08 23 1003 6.8 9 285 59.0 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 --------------------------------------------------------------------------- 08 17 2203 159 9 1 2 11 49 88 292 584 354 08 18 1033 130 9 1 3 6 92 73 264 311 176 08 19 0933 78 4 0 2 6 26 39 41 90 86 08 20 2203 115 3 1 2 12 35 68 24 23 414 08 21 2303 183 7 7 19 8 56 143 42 361 939 08 22 0403 127 3 9 95 7 56 125 109 30 246 08 23 1003 211 9 3 33 62 35 63 164 1121 480 Daily Swell Inspection Program for today: NAME DAY TIME HEIGHT PERIOD SST (PST) (FEET) (SECONDS) (DEG. F) # 66 Ocean Station Papa 23 1003 12 9 58.1 # 05 West Washington State 23 1040 7 10 n/a # 02 West Oregon The buoy went adrift 02/09/19 # 06 SE Papa 23 1050 5 17 70.2 # 59 California 23 1000 7 8 70.2 # 44 Humboldt Bay Waverider 23 1000 8 9 55.4 # 29 Point Reyes Waverider 23 1033 9 9 58.5 # 42 San Francisco Sandbar 23 1000 5 17 60.2 # 15 Monterey Waverider Buoy 23 1003 7 9 58.6 # 28 Cape San Martin The buoy went adrift 04/04/19 # 76 DCPP Waverider 23 1003 7 9 59.0 # 22 Santa Lucia Escarpment 23 1003 8 10 63.0 # 11 Point Arguello 23 1050 7 9 59.7 # 63 Harvest Buoy 23 1050 8 9 60.8 # 19 San Nicolas Island 23 1033 6 17 63.9 # 20 Scripps 23 1022 2 9 66.9 # 33 Pearl Harbor Entrance 23 1000 3 13 82.6 # 04 SE Hawaii 23 1040 6 8 81.9 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): 0.01 inches Average season rainfall at DCPP to date: 0.15 inches Ocean Lab Barometer: 29.89 in/Hg or 1011.8 mb -0.9 mb (Falling) Today's Sunrise 6:29 AM Sunset 7:42 PM Tomorrow's Sunrise 6:30 AM Sunset 7:41 PM Tides: Low Tide High Tide AM PM AM PM 23 Friday 9:25 2.6 ----- --- 4:51 3.3 4:20 5.0 24 Saturday 10:33 2.8 (12:00 1.2) 6:38 3.3 5:19 5.2 25 Sunday 11:49 2.9 (1:02 0.7) 7:51 3.5 6:18 5.6 26 Monday 1:53 0.1 12:56 2.8 8:39 3.8 7:14 6.0 27 Tuesday 2:39 -0.4 1:54 2.5 9:18 4.1 8:06 6.4 28 Wednesday 3:22 -0.7 2:47 2.2 9:54 4.4 8:57 6.6 29 Thursday 4:03 -0.9 3:39 1.8 10:30 4.7 9:47 6.7 30 Friday 4:43 -0.9 4:30 1.4 11:07 4.9 10:38 6.5 31 Saturday 5:24 -0.6 5:24 1.2 11:45 5.2 11:30 6.1 1 Sunday 6:04 -0.2 6:21 1.0 12:24 5.4 ----- --- 2 Monday 6:45 0.4 7:23 0.9 12:25 5.5 1:07 5.5 3 Tuesday 7:28 1.1 8:32 0.9 1:27 4.8 1:53 5.5 ======================================================================== This day in weather history 1933 - The Chesapeake-Potomac hurricane moved over Norfolk VA and Washington D.C. A tide seven feet above normal flooded businesses in Norfolk, and damage in Maryland was estimated at seventeen million dollars. 2010 - The southwesterly (Avila Beach and Cayucos) facing beaches will warm to the high 80s into the low 90s. The coastal valleys (San Luis Obispo) will hit low to mid 90s, with the North County reaching the low 100s. To the east, California Valley is forecast to reach 108 degrees. Tuesday will be very similar to Monday with winds blowing from the north to northeast (offshore) in the morning. ======================================================================== 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