Tag: california weather

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Rain, 2014 Style

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There it is: what you might refer to idiomatically as the sum total of Berkeley rainfall — or at least the rainfall we have seen here in the North Berkeley flatlands — for the entire month of January so far. When the drizzle started coming down last Saturday, I grabbed the camera and ran out to take a picture. It was just enough to moisten the pavement or the bottom of a rain gauge or, as above, to bead up on windshields.

And from what the weather forecasters, the paragons of prognosticatory pessimism, are saying, this is the only rain we can expect to see through the end of the month. Which means we’re starting 2014 with the driest January on record. Here’s a brief synopsis of where the rain season stands from the National Weather Service’s Bay Area forecast discussion:

SAN FRANCISCO`S CURRENT WATER YEAR TOTAL IS 2.11" WHICH IS NOW THE
THE DRIEST WATER YEAR TOTAL TO DATE ON RECORD. THE OLD RECORD WAS
2.26" THROUGH JANUARY 15TH SET BACK IN 1917. SAN FRANCISCO IS
RUNNING AROUND 9" BEHIND AN AVERAGE YEAR. IF NO ADDITIONAL RAINFALL
IS RECORDED BY THE END OF THE MONTH, SAN FRANCISCO WILL BE 11.50"
BEHIND NORMAL.
SAN FRANCISCO AVERAGES AROUND 8 DAYS IN JANUARY WHERE MORE THAN A
TENTH OF AN INCH OF RAINFALL IS REPORTED. THIS YEAR WE HAVE HAD
ZERO DAYS SO FAR. IF THAT HOLDS, IT WILL MARK THE FIRST TIME IN SAN
FRANCISCO`S HISTORY THAT AT LEAST ONE DAY IN JANUARY DID NOT PICK
UP MORE THAN A TENTH OF AN INCH.

And that, friends, kinds of puts things in perspective. What we’re seeing now hasn’t been seen since 1849, the beginning of San Francisco’s rain record.

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California Water: Enough for Everyone Except You Fish

The results of the state Department of Water Resources monthly snowpack survey are in. On the surface, the news looks good. The snowpack is 115 percent of normal for the end of January, and nearly double the amount for a year ago, when we had gone through a very dry January. But the state water managers want to make sure we don’t think the glass is half-full:

“Today’s snow survey offers us some cautious optimism as we continue to play catch-up with our statewide water supplies,” said DWR chief deputy director Sue Sims. “We are still looking at the real possibility of a fourth dry year. Even if California is blessed with a healthy snowpack, we must learn to always conserve this finite resource so that we have enough water for homes, farms, and businesses in 2010 and in the future.”

True, true: Our water account has not been replenished to the point where we can start writing blank checks again. Maybe, given our growing population, we’ll never have that sense about water again. Losing that mindset, in fact, would be a good thing. To the degree that Chief Deputy Director Sims reminds us of that, I applaud her.

But it’s notable that she omits the California environment from her list of clients for the state’s precious water supplies. Maybe she’s not aware that the state is now populated by a host of endangered fish species, once-abundant populations that have been driven to the brink of extinction in large part because of the way we have managed water and aquatic ecosystems.

In reality, of course, Sims and everyone else in the state’s water bureaucracy know all about the fish issue–in fact, they can’t help but be preoccupied with it. So declining to mention the environment in a statement like this is really a kind of negative policy statement about who ought to get water and who will have to fight for it.

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California Water: Is the Drought Over?

Is California’s drought over? OK, let me take a step back. Yes, I realize one could debate whether the last three years in California actually constitute a drought. But that’s a discussion for another time. For now, I think everyone can agree that we’ve had lower-than-average precipitation for the past three years.

The only reason to ask the question is that, after the first half of the wet season delivered only spotty rain, we’ve had a pretty solid week of downpours. Water is sluicing into our reservoirs, and the hills are greening up. All of that is a sign of what we think winter should be here. ( My favorite water statistic of the week: when the storms were at their heaviest around Lake Shasta, California’s biggest reservoir, water was flowing into the lake at about 500,000 gallons per second. That’s 1.5 acre feet, or about enough for three “average” households for a year, every second.*)

Amazing numbers like that aside, the people who get paid to think about whether the drought is over say “not yet.” The San Jose Mercury News published a good summary of the situation a couple days ago: “It’s soaking. But the drought’s not over just yet.”

That story does contain one bit of typically odd California thinking about rain and water, though. It quotes a very knowledgeable local meteorologist, Jan Null, about where we stand in terms of normal rainfall. He says: “”We need February and March to be wetter than January to really end the drought. You have to look at the long game here. This is a great start, but we need to keep it going.”

The last sentence stopped me: “This is a great start, but we need to keep it going.”

Of course, Mr. Null recognizes better than most that the amount of rain we get and when we get it is out of anyone’s control. Still, “we’ve got to keep it going.” Maybe he’s a professional rainmaker.

Once you understand the importance of water in California, once you get how crucial the winter rains are, there’s a score-keeping aspect to weather-watching here. It becomes second nature to study the rain gauge and the seasonal precipitation table as an index of performance, a reflection on whether a great collective goal is being attained. Lots of rain means we’re doing well (and that we can put the complexities of water supply out of our minds). A dry spell means we’re failing (and that there will be hell to pay, or at least the strong possibility of stringent conservation measures).

But in reality, there’s no performance going on. The rain is the rain, and the climate is the climate. California’s rainfall is famously variable. Dry spells can be counted on, and the current run of dry years is the third we’ve had since I arrived in Berkeley in the ’70s. My first California winter, 1976-’77, was bone dry and was in fact the second year of the driest two-year period ever recorded here. A decade later, from roughly 1986 through 1992, we had another run of dry years. And if our winter rains were to stop now, we’d be in the fourth year of drier-than-normal years. In between these periods we’ve had average years and very wet years and years that didn’t quite hit the average. That might not be too different from anywhere else. The reason it’s a bigger deal here than it might be in, say, central Wisconsin, is that we have a six-month dry season, we need to store water to get through that, and we have 37 million people and millions and millions acres of farmland that need water whether it’s falling from the sky or not. Thus the need to believe we can wish the rain to keep going during the wet season and the tendency to feel disappointment when the winter turns into a string of dry, sunny days.

*500,000 gallons per second. Here’s the arithmetic: California Department of Water Resources figures (here: http://bit.ly/6HzIuu) show that in the hour between noon and 1 p.m. on Tuesday, January 19, the net inflow into the lake was 66,288 cubic feet per second. That’s the highest inflow figure for any single hour all week. One cubic foot equals 7.48 gallons. 66,288*7.48=495,834.24 gallons. One acre foot=325,851 gallons. And 495,834.24/325,851=1.52 acre feet. Per second. For the entire 24 hours of the 19th, Lake Shasta’s inflow averaged just over 1 acre foot a second.

Bonus feature! KQED’s latest California Reservoir Watch map, updated earlier today:


View KQED: California Reservoir Watch in a larger map

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A Fan’s Notes on Water Supply

When you first move to California from someplace where rain is just a normal part of life all year round, some of the information that shows up on the newspaper weather page seems a little odd. I'm thinking especially of the rainfall totals, calculated between July 1 and June 30, and of the reservoir and snow-depth reports. Yeah, it's vaguely comforting to know some big lake somewhere is nearly full of water, and it's troubling when it's not. The snow report makes sense when you, the auslander, learn that a lot of the water that will wind up in the reservoirs starts out as vast quantities of white stuff in the higher reaches of the Sierra Nevada. The snow and water tables in the paper generally include references  to the total for a year ago and to what's "normal" for the date. If you spend any time at all on the weather page, you develop a sort of rooting interest. Wet years with more than 100 percent of the expected rain and snow can make you feel like the home team is playoff bound. Dry years resemble those lost seasons when all the supposed stars flop and nothing quite goes right.

If the precipitation and snowfall reports are the daily standings of the water year, then meteorologists  serve as both play-by-play announcers and analysts. If you're a serious fan and want to go beyond the entertainment offered by most TV weather presenters or the few vague words that make up most newspaper and online forecasts, then you have to go to the meteorological analyses published online by government weather services. Even in that world, there are circles within circles: for the interested generalist, there's the Area Forecast Discussion posted several times daily by most National Weather Service offices (for example, here's the AFD from the Monterey, California office). Informing those discussions are weather models–vastly complex, supercomputed pictures of the weather many days into the future; the true weather fanatic learns at least the rudiments of the models, their individual peculiarities, and what they might mean in terms of observable local weather.

Me, I haven't pushed the geek level much. I'm pondering the meaning of terms like "500mb heights" and  "pressure surfaces" but don't employ them in polite company or even bar-room conversation. However, my interest is real. We're nearing a key date in our water year–the California Department of Water Resources will take its first formal snow measurements of the season in a couple of days. Fans will be watching closely because frankly our 2009-2010 water year hasn't gotten off to a great start; while most reservoirs are a little fuller than they were a year ago, most are also well under average levels.

Now, while I'm waiting for the pre-measurement festivities to begin, I'm consulting the oracles of the sport. Among my newer winter weather reading is the California-Nevada River Forecast Center's daily "Hydrometeorological Discussion." Issued at 9:30 a.m. every morning, it summarizes rainfall and snowfall for the last 24 hours, then reviews what the weather models are saying about incoming storms for the next three days. Whereas the Area Forecast Discussion focuses on conditions in the geographic districts they cover, the CNRFC discussion looks at conditions in watersheds and river drainages. If you live in California and you're preoccupied with  water supply, the rain falling in the mountains above Lakes Shasta and Oroville, the state's two biggest reservoirs, probably means a lot more than whatever happens to fall on your neighborhood–where there's no place to store all the water that's coming down.