Update, Oct. 26, 3:30 p.m.: Final rainfall totals from the atmospheric river storm this weekend hit almost 9 inches in some parts of Berkeley — more than seven times above the annual October average for the city, according to the National Weather Service.
As of Tuesday, the highest rainfall total reported at an NWS station in Berkeley was 8.67 inches at a monitor in the hills at Lawrence Berkeley National Laboratory at the top of the hills. The totals were a little lower in the flats. A gauge near Ohlone Park got 7.95 inches and one near Strawberry Creek Park got 7.01 inches.
“The fact that [Berkeley] got 8.67 inches in just one storm, and the entire monthly average is 1.19 inches — it’s an impressive event,” NWS meteorologist Brooke Bingaman said, referencing a special NWS climate database that tracks historic rainfall.
In comparison, San Francisco typically receives 0.64 inches of rain in October, and received a downpour of 7.04 inches, 11 times higher than the monthly average, with this storm.
These values reflect totals from when the storm began in Berkeley on Saturday evening at about 8 p.m. through Monday.
On Monday, Berkeleyside reported incomplete 24-hour totals from Sunday afternoon to Monday afternoon, which came in at about 3 inches in the Berkeley flats, according to the National Weather Service. Totals between 5 to 7 inches were reported during that time period in the Berkeley Hills, according to monitors at the Berkeley Lab and Balance Hydrologics.
Original story, Oct. 25: Berkeley Hills resident Gaurav Kumar was observing the rain storm and taking in the view at the Berkeley Rose Garden on Sunday when rushing water in a small section of the park caught his eye.
He walked down to the spot where Codornices Creek bisects the park and managed to capture a stunning video of muddy waters surging into the air as the creek completed a small curve leading downhill.
“When I saw that from pretty far off, I was pretty surprised,” he said, explaining that the physics of the small area made the water burst forth with extra force. “It was definitely very captivating — and very stunning — and I enjoyed watching it.”
Gaurav Kumar @coffee_buff sent in this video from the Rose Garden: pic.twitter.com/rBTJzt4VkR— Supriya Yelimeli (@SupriyaYelimeli) October 25, 2021
Nearly 3 inches of rain poured down in Berkeley during the “atmospheric river” storm on Sunday, doubling averages for the month of October locally and breaking rainfall records throughout the Bay Area. In San Francisco, the National Weather Service recorded the fourth wettest day ever with 4 inches of rain (the record holder day was in 1927, with 5.4 inches).
There were numerous local impacts like power outages and infrastructure issues, as well as flooded apartments. In a 24-hour period, city staff responded to reports of flooding at 66 locations and received 44 reports of downed trees, limbs and debris. Homeless encampments throughout the city also asked for clothing and supply donations as the first large weather event of the winter set in. Residents at People’s Park are accepting donations through a payment app to purchase supplies, and residents at the “Here There” encampment on Adeline Street are asking for tarps, cardboard, blankets, tents and umbrellas.
Considering a longer timeframe, the storm was largely beneficial rain, according to NWS meteorologist Sean Miller. The powerful surging creek captured in the video at the Berkeley Rose Garden also didn’t cause damage.
The creek often overflows in the garden during heavy rains, and Parks Director Scott Ferris said this storm made for a “pretty amazing” display. Ferris said the rain and wind did not result in significant damage at the Rose Garden, or any other Berkeley parks.
“We had a few trees fall, but outside of that we’re in pretty good shape,” Ferris said.
Miller said the Bay Area doesn’t usually see this kind of rain until the peak of wet season in January, and it’s too early to predict themes or patterns in rainfall, but it was a positive event. Rainfall totals vary largely by terrain because cooler areas at higher elevations are able to “wring” out more moisture, he added, so significantly higher numbers were recorded in the Berkeley Hills.
“It was a strong event, and it was interesting to have this arrive this early in the season,” he said.
The rain is expected to allay concerns about wildfires through the end of this year, but Cal Fire is still assessing its data from the storm and determining what it means for a region, and state, that has suffered 10 years of inadequate rainfall. Cal Fire may reduce staff if the rain’s positive impacts are significant enough.
“The reality is — it’s going to take more than one rain storm to put us outside of peak conditions,” Cal Fire Batallion Chief Jon Heggie said, explaining that vegetation has to first absorb the rain that poured down on it to become less fire-prone. “In California, we never go out of fire season; we just go into different states of preparedness.”
Ultimately, the amount of moist vegetation will have to outweigh the accumulated dry vegetation in the state. Heggie said that would require between five to six years of sustained rainfall, but this weekend’s storm is still a positive event.
There were no major mudslides or mudflows reported in the lower elevation areas of Berkeley, but locations throughout the region that have burn scars are at risk when it rains, and Heggie said to be “uber-vigilant” if residents live near such locations.
The storm is over as of Monday and Miller said there are no significant weather conditions forecast for the coming weeks.