A large area of high pressure over the west brought excessive heat and dry conditions to the region. Numerous record high temperatures were broken with 13 broken records on Sunday the 6th alone including records set that weekend for the month of September.
Every event with a place to put it; 8 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MTR wrote it up.
A large area of high pressure over the west brought excessive heat and dry conditions to the region. Numerous record high temperatures were broken with 13 broken records on Sunday the 6th alone including records set that weekend for the month of September. Temperatures over the long weekend breached 110 degrees across the interior with 90s along the coast to start the weekend and even reaching 100 degrees in San Francisco on Sunday. Once the ridge began to break down towards the end of the weekend, offshore winds increased flaring up some of the wildfires that were ignited during August's lightning storm. These winds also enabled smoke from various wildfires across the state to blanket much of the Bay Area. The skies were tinted orange and red with ash accumulating for many locations.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS San Francisco Bay Area, CA wrote its last area forecast discussion before the first event at Sep 6, 10:00 AM PST, 3 hours earlier.
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</html>The national radar mosaic for the moment the first event began.
6 excessive heat, 3 strong wind, 1 rip current, 1 dense smoke. Local standard time, as filed.
Downtown San Francisco reached 100 degrees on Sunday breaking a previous daily record of 92 degrees in 1904.
Two locations in the North Bay Valleys tied previous record high temperatures for the month of September. Kentfield with 108 degrees and Napa with 110 degrees.
Gilroy tied a previous record high for the month of September at 112 degrees.
The San Francisco Fire Department rescued four surfers caught in a rip current the evening of the 6th https://www.thesfnews.com/four-caught-in-rip-current-labor-day-weekend/66401.
The city of Richmond tied its all time record high temperature at 107 degrees.
The city of Napa broke its record high temperature for the month of September at 111 degrees.
The city of Santa Rosa tied its record high temperature for the month of September at 110 degrees.
Healdsburg Hills North mesonet (PG&E) measured gusts between 45 and 55 mph with a peak gust of 58 mph.
Diablo-Blackhawk mesonet (PG&E) station reported 35 to 45 mph gusts.
After a brief lull, the Healdsburg Hills North mesonet (PG&E) station recorded gusts 45 to 55 mph with a peak gust of 59 mph.
Smoke from multiple wildfires across the state of California produced red and orange skies over the San Francisco Bay area as ash fell across much of the region https://abc7news.com/smoke-in-the-air-today-why-is-sky-orange-bay-area-quality-california/6415624/.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2020Every state in 2020This day in weather historyWarnings in California, September 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 918113, 918114, 918115, 918127, 918116, 918117, 918118, 917319, 917321, 917320, 918119.