After light showers Friday and Saturday and a steadier drizzling rain much of Sunday, we got heavy rain Monday morning. Just like the weather forecasters and their models predicted. But the summary of coming weather rarely does justice to the reality. In Monday’s case, a pounding early morning rain gave way to showers and then a long, windy break complete with a few flying patches of blue sky. We went out to the Albany Bulb–the old garbage dump of the little suburb just north of us that protrudes into the bay–and gave the dog a run. How was it out there? Blustery, windy enough that a little swell had come up on the Bay and waves were driving all the way up the pocket beach near the Golden Gate Fields racetrack. It started showering again pretty soon after we got back to the car. The next storm arrived, as predicted, early, early this morning, Tuesday. It was heralded by long, deep peals of thunder that at first only The Dog was hearing–he growled every time one sounded. Just before daybreak, the sky opened up for about four hours of thundering, pounding rain. Water shot down the gutters, and all day after and tonight, too, water seems to be flowing everywhere. We had some heavy showers through the day, and tonight the next storm is moving in. It’s supposed to be more intense than today’s. On my last walk with The Dog this morning, I could have sworn I heard a rumbling in the distance, something gathering itself to roll in across the coast; either that, or a string of diesel engines getting ready to roll up the Southern Pacific tracks just west of here.
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.
Chicago Weather Update: Midwinter Slop
Alley, Oakley Avenue between Greenleaf and Estes, Chicago.
Journal of No-Look Windshield Photography
The holiday-lit peristyle of Soldier Field, captured as I drove past during last night’s odd snow nonstorm (the nonslaught, which continues to nonrage this morning, consists of constant extremely light snow accumulating at the rate of “a few tenths of an inch per six hours,” according to the National Nonweather Service).
The Forecast, Chicago Style
As mentioned many times in the past, we here at Infospigot Information Industries are fond of reading the Area Forecast Discussion (AFD) published online by National Weather Service offices around the country. The AFD gives a broad-brush explanation for the upcoming forecast; they discuss the latest trends in the output from the numerous weather models they follow and give the rationale for why they believe it will be windy and cold but dry tomorrow and the next day instead of warm and rainy. It would not seem to be the kind of writing that has a lot of character to it. Most of the time it isn't. Every once in a while, though, some personality leaks through. In this morning's discussion of upcoming weather from the Chicago office, a forecaster mentions that the weather models show that storms next week will be warmer than expected. Thus the region can expect rain instead of snow. But what about white Christmas? Here's the forecaster's summary (with some of the arcane AFD abbreviations spelled out and the all-caps style left intact):
HEADING INTO EXTENDED RANGE…GUIDANCE HAS MADE A MAJOR SHIFT IN SCENARIO WITH MID WEEK WEATHER SYSTEM. GFS [GLOBAL FORECAST SYSTEM MODEL] NOW BRINGS DEEPENING LOW NORTHWARD ACROSS ILLINOIS WEDNESDAY NIGHT-THURSDAY SUGGESTING MAINLY A RAIN EVENT FOR MOST OF FORECAST AREA. 00Z [6 P.M. CST THURSDAY] EUROPEAN [MODEL] HAS COME IN FOLLOWING SUIT. THIS LOOKS LIKE A VERY SIMILAR SITUATION AS WHAT WE HAD THE FIRST WEEK OF THIS MONTH. THEREFORE…RATHER THAN RIDE COLDER SNOWY FORECAST INTO THE GROUND…HAVE BEGUN TO TREND AS WARM WITH THIS SYSTEM AS GRID TOLERANCE WILL ALLOW. HOPE NO ONE GOT THEIR KIDS SLEDS FOR CHRISTMAS UNLESS THEY CAN BE ADAPTED FOR USE IN MUD."
As I said, these folks can be a riot. (Picture above: the current GFS Model Forecast from Unisys Weather.)
Road Blog: Chicago Skyscape
At Western and Coyle avenues on the far North Side. It was warmer today — we were above the freezing mark — partly because we were under a blanket of overcast all day. Then, just as the sun set, the sky got some color. I went out around the corner from my sister's place to try to get a picture and had to go down Western a little way before I had a view past the street-front buildings to the west. Snow is in the forecast for tomorrow and the next day (Friday and Saturday), though it seems like sort of a non-storm event: continual light snow that may or may not wind up with a few inches on the ground. I'm supposed to fly back to San Francisco on Saturday, so I'm rooting for no big storm until I've escaped.
Dramatic Proof: It’s Cold
It was cold enough in the Bay Area Tuesday that we saw the rare phenomenon of visible midday respiration (translation: you could see your breath in broad daylight). After dark, the temperature fell into the 30s again here in Berkeley (into the lower 20s farther from the bay, and below zero up in the Sierra Nevada–but that’s not our neighborhood). Last night, we saw billowing clouds of Midwest-style breath steam just like the one captured above in a dramatic candid photograph.
Your Berkeley Weather Outlook: Nice; Really Nice
At the risk of unleashing a wavelet of hate mail, here’s a quick take on the Berkeley weather for this week. Meantime, the calendar says it’s November. Please remind me of this when next I snivel about the cold and rain. Of course, in the next 48 hours I’ll hear someone spoil the party by saying global warming is responsible for the continued warm, dry conditions.
Bay Area Storm Numbers
The storm came, and now it has gone, mostly. It was advertised as the marriage of a Gulf of Alaska storm and some typhoon remnants. Watching the rain pour down here, and seeing the totals mount on the National Weather Service statistics pages, I believe the typhoon part. It was the heaviest mid-October rain for most locations since 1962, when the World Series–Giants and Yankees, at the still-new Candlestick Park–was washed out by rain.
Some of the more amazing 24-hour totals, midnight Monday to midnight Tuesday: Mount Umunhum in the Santa Cruz Mountains, 13.07 inches. Ben Lomond, Santa Cruz Mountains: 10.58 inches. Mining Ridge, a remote recording station at an elevation of 4760 feet in the Santa Lucia range above Big Sur: 20 inches even. The totals of 5-plus inches at lowland locales in the central Bay Area seem semi-arid by comparison–even though they represent anywhere from 15 to 25 percent of what those locations get in an average rain year.
It’s not easy to get apples/apples numbers just casually browsing the Weather Service sites. But the service did publish a record report for 24-hour rainfall (the standard here is from 5 p.m. to 5 p.m., I think).
| Location | New Record | Old Record |
| Kentfield | 6.14 | 4.20, set in 1957 |
| Oakland Museum | 3.86 | 0.37, set in 1988 |
| Richmond | 3.38 | 2.47, set in 1962 |
| San Francisco Airport | 2.64 | 2.62, set in 1962 |
| San Francisco Downtown | 2.49* | 1.80, set in 1962 |
| Santa Rosa | 2.74 (tied) | 2.74, set in 1962 |
| King City | 1.65 | 0.30, set in 2007 |
| Monterey Climate Station | 2.66* | 1.14, set in 1962 |
| Salinas | 1.05 | 0.39, set in 1992 |
| Santa Cruz | 3.16* | 2.49, set in 1957 |
*New unofficial record for 24-hour rainfall in October.
For several days before yesterday’s storm, the Weather Service office in Monterey was highlighting some of the highest October rainfall totals for stations in its forecast area. Here they are:
| Location | One-Day Record | Two-Day Record |
| Santa Rosa | 4.67 (10/12/1962) | 7.41 (10/12-13/1962) |
| Napa | 4.66 (10/13/1962) | 9.32 (10/12-13/1962) |
| San Francisco Downtown | 2.29 (10/15/1969) | 3.72 (10/12-13/1962) |
| San Francisco Airport | 2.62 (10/13/1962) | 4.56 (10/12-13/1962) |
| Oakland Airport | 4.53 (10/13/1962) | 5.85 (10/12-13/1962) |
| Livermore | 2.17 (10/13/1962) | 3.45 (10/13-14/1962) |
| San Jose | 3.22 (10/13/1962) | 4.56 (10/12-13/1962) |
| Santa Cruz | 3.15 (10/20/1899) | 3.35 (10/20-21/1899) |
| Monterey | 1.80 (10/26/1907) | 2.09 (10/26-27/1907) |
| Salinas | 1.50 (10/30/1982) | 1.50 (10/30-31/1982) |
| King City | 1.88 (10/29/1996) | 2.18 (10/29-30/1996) |
Source: National Weather Service, Monterey, California
Morning Dew
Saturday evening, he had abundant low, thick clouds scudding in off the Bay. Not unusual. Less common: The air was warm and felt very wet. That gave way Sunday morning to very heavy dew. (The shorthand physical explanation: the air was near saturation with water and when the temperature fell to the “dew point” — in the mid-50s that night, I think — the water in the air was deposited on cars, lawns, and what have you.) On our way back from our usual Sunday morning walk down to the old Santa Fe right-of-way, Kate noticed a patch of grass in one yard on Rose Street, each stalk covered with beads of water. So–that’s where these pictures came from. (Click for larger versions.)