Editor’s note: This is a rapidly developing situation and we’ll be updating this article continually, so for the original reporting scrolls down. Also larger graphics and PDFs may be placed at the bottom of the page to aid with initial load speed.
UPDATE 11/19/19 — Here is our latest:
PG&E rolls back scale of shut-offs; now only Hopland area will go dark
UPDATE 11:40 a.m. — We’re now getting some specifics about where the outages will likely hit on Wednesday morning: around Gualala and Hopland. This situation could change, both because weather is actually not up to humans nor totally predictable, and because, as we’ve seen now several times, PG&E does not communicate well and can be capricious.
As to the maps, here is a link to a PG&E page where they appear to have lots of maps in PDF form, though not labeled clearly.
Here’s what the County of Mendocino said in a press release issued minutes ago:
PG&E Public Safety Power Shutoff (PSPS) Scheduled for November 20, 2019 through November 21, 2019
Post Date: 11/18/2019 11:29 AM
The County of Mendocino has been notified by Pacific Gas and Electric (PG&E) that power may be turned off in our area due to high risk weather conditions on November 20, 2019. At this time approximately 3,000 Mendocino County customers are estimated to be effected in the following areas: McNab Ranch south through Hopland to the County line and the Gualala area along the coast approximately half way to Point Arena. Chief Executive Officer Carmel Angelo stated, “Like past events the information is very dynamic and can change minute by minute. Please be aware the County is dependent on PG&E to provide accurate, updated information that can be shared with the public. Mendocino County will continue to closely monitor the situation and share update as we receive them from PG&E.”
De-energization will be initiated by PG&E and is estimated to occur at 5:00am on November 20, 2019, prior to the start of the 8:00am wind event. PG&E estimates the wind event will last 24 hour, concluding on November 21, 2019, at 8:00am. Following the “all clear” on the morning of November 21, 2019, PG&E will begin power restoration. The County will release any updated information on the power outage and re-energization timelines as they become available.
For more information, please contact the Executive Office at 707-463-4441. For updated County information on the public safety power shut off, please visit www.mendocinocounty.org/psps or follow the County on Facebook at https://www.facebook.com/mendocinocounty and twitter https://twitter.com/countymendocino.County of Mendocino
UPDATE 9:55 a.m. — We have gotten confirmation for the first time that portions of Mendocino County will have their power cut. Supervisor Ted Williams of the Fifth District posted the following information on Facebook. Beginning at 4 a.m. Wednesday morning 3,076 customers in Mendocino County will have their power turned off. The wind is scheduled to blow through Wednesday night, and PG&E expects to call the “all clear” Thursday morning. The all clear is the signal that weather conditions have sufficiently abated to begin the process of turning the power back on — that process involves a manual check of every mile of power line and could last from a day to several days, but is likely to only take about a day. So some residents of Mendocino County can expect to be without power from Wednesday morning through Thursday evening or Friday.
Apparently all of the shut-offs in Mendo will happen in phase one of the PSPS. Here’s what Williams had to say:
PSPS Forecast (as of 9am Monday Nov 18)
Mendocino County is scheduled to be included in Time Period 1 with Colusa/Lake/Napa/Solano/Sonoma/Yolo.
Wednesday 4am – shut off
Wednesday 7am – wind event arrival
Thursday 8am – all clear
Some time after inspections – restoration
Only 70,391 customers are included in the Time Period 1 outage, including just 3,076 in Mendocino County. We’re awaiting maps and remain aware that PG&E stories change. South Coast should prepare to be included.
There is still considerable uncertainty regarding the strength, timing and humidity levels with this system.District 5 Supervisor Ted Williams
MENDOCINO Co., 11/18/19 — Pacific Gas & Electric has raised their rating for the “potential” for planned power outage from merely “elevated” to a “watch,” making it extremely likely that some part of the North Bay will have their power cut — though whether this will significantly affect Mendocino County remains unknown.
(See our previous article for a more detailed breakdown of the weather forecast)
They announced last night that they would likely be shutting off power to 250,000 customers in 19 counties, with conservative estimates placing the number of people at around 750,000. It should always be remembered that PG&E counts customers, which include businesses, schools, and households — not individual people — and that whole cities that run their own power grid, like Ukiah and Healdsburg, are counted as one customer.
Also unclear is whether this change in rating, which was made late last night, reflects a change in forecast, or if it is the result of increased confidence in the forecast, or increased confidence within PG&E’s management as to the decision they’ll take — the power utility’s decision making process remains fundamentally opaque, and we learned last month that the decision ultimately just comes down to three guys.
Indeed, while winds are expected to reach 30 mph in parts of Sonoma, Napa and Lake counties, and to gust above 45 mph in certain places farther east, Mendocino County will likely experience some relatively calm nights and days, with relatively higher humidity than in other areas.
Again, where exactly this “public safety power shut-off” (PSPS) will happen is unknown to the public, and potentially unknown to PG&E executives as of this moment, or as PG&E puts it: “PSPS decisions are made at more granular levels; thus, only a portion of a zone may experience a PSPS event.”
The key question seems to be whether the “wind event” becomes strong enough to require the de-energizing of only distribution lines, or of both high voltage transmission lines and distribution lines. An electrical grid is analogous to a road system, with narrow side streets and residential streets that carry little carry little traffic, and larger thoroughfares and freeways that carry lots of traffic. In the case of the gird, the lines that run directly to houses, schools and businesses are called “distribution lines,” and have a lower voltage. They are also usually lower to the ground, have weaker poles, and are more likely to come in contact with brush and tree limbs.
In contrast the high voltage “transmission lines” can be thought of as freeways. They lines are usually higher, with stronger poles and towers, and are less likely to be obstructed by vegetation.
Because the distribution lines are more likely to break, fall, or be struck by a tree — and because they can be shut off in a more localized fashion — there is a lower threshold for turning off these lines. However, if PG&E does turnoff the larger, and hardier, transmission lines, that can mean that tens of thousands of people downstream of that point, people who are not experiencing fire weather or extreme wind, can also lose power.
This, along with substantial damage to lines caused by the Kincade Fire and the wind event itself, is the situation that resulted in so much of Mendocino County losing power last time — even in places like Fort Bragg where the fire risk was minimal.
So this next shut-off could look like the last one, where the whole county goes dark, or it could look like one of the ones before that where only small portions of the county that are actually experiencing high winds have their power cut — we just don’t know right now.
Either way we’ll continue to update you as soon as new information comes in, so check back with The Mendocino Voice, and this article for the latest.
Here is PG&E’s forecast for Monday morning:
Monday, November 18, 2019
NOTE: This forecast is based on weather conditions and fuel moisture content only and does not include other criteria used to determine whether a PSPS may be necessary.
A strong north or northeast wind event is expected to develop late Tuesday into Thursday this week, generally affecting the northern half of the PG&E territory. There is still considerable uncertainty regarding the strength, timing and humidity levels with this system and some changes in the forecast are possible moving forward. Nonetheless, there is an increasing possibility that gusty winds will result in critical fire weather conditions. The National Weather Service (NWS) has issued Fire Weather Watches that will likely be upgraded soon to Red Flag Warnings for many areas across central and northern California due to the potential critical fire conditions. Northern Operations Predictive Services is forecasting a high risk event and increased potential for significant fires due to these dry and gusty winds. Please refer to weather.gov, https://gacc.nifc.gov/oncc/, or https://gacc.nifc.gov/oscc/ for the latest updates from federal forecast agencies. As a result of the potential critical fire weather conditions, Geographic Zones 2, 3, 4 and 5 are now under a PSPS Watch for Wednesday and Thursday. The PG&E Emergency Operations Center remains activated to monitor and prepare for the event.
Details: High pressure will hold over the PG&E territory today for continued dry weather and warmer than normal temperatures. Expect maximum temperatures away from the immediate coast to rise into the 70s to low 80s and that is 10 – 20 degrees above normal for mid-November. A low pressure system is then forecast to move southward through the territory tomorrow for cooler weather and a chance for showers along the North Coast and Sierra before moving into southern California mid-week. The storm is forecast to produce shower activity both days across the southern part of the state including possibly the southern areas of the territory, primarily Kern county. High pressure will build into Oregon over that time frame and gusty north or northeast winds are favored to develop across the northern half of the state on Tuesday evening and into Thursday. Strong wind gusts in excess of 50 mph are possible across the elevated terrain in the SF North Bay in addition to the northern Sierra foothills. Winds will not be as strong across the low elevation areas outside of the Sacramento and northern San Joaquin Valleys where gusts up to 40- 45 mph are possible during the day Wednesday. Winds are forecast to decrease by Thursday night with light winds expected for the rest of next week and next weekend. Most of northern and central California has not received any significant precipitation this fall and fire potential is well above normal as live fuel moisture remains below critical values for mid-November and dead fuel moisture is at historically low levels in many areas. The CDEC Northern Sierra 8 station index has only observed 0.3 inches of rain in Oct and Nov to start the water year. This a paltry 4% of normal. If no rain occurs in the northern Sierra for the remainder of November, it would be the driest start to the water year in 60 years and tied for 2nd driest in the past 100 years.
Please note: This forecast is published daily by an operational meteorologist from PG&E’s Meteorology and Analytics team. This forecast has been customized for PG&E utility operations and should not be used for any other purpose or by any other entity. This forecast only provides a broad overview for a potential Public Safety Power Shutoff (PSPS) event in the next 7 days as determined from an analysis of forecasted weather, the potential for wind-related damage, and fuel moisture content in dead and live vegetation. It is not a fire danger forecast. The forecast is broken down by broad PG&E Geographic Zones numbered 1 – 9; however, PSPS decisions are made at more granular levels; thus, only a portion of a zone may experience a PSPS event. While a PSPS event may not be expected for an area, due to the interconnectivity of the grid any location within PG&E territory may be subject to PSPS event.PG&E
Here’s yesterday’s report: