Tomorrow’s event, part two of the qualifying series for this August’s Paris-Brest-Paris exercise in transatlantic self-punishment, is a 300-kilometer ride. That’s 188 miles in universally recognized American distance units. We’ll start at the Golden Gate Bridge at 6 a.m., ride up through the interior valleys of Sonoma County to the town of Healdsburg, head out along the Russian River to the townlet of Jenner, then ride down the coast highway to Point Reyes Station, where we’ll swing inland to go back to the bridge (the foregoing provided for those who want to keep score at home). Based on past experience, this will be something I’ll be doing well into the evening.
The hard part is: rain. The sky is clear out there now. But for the past two or three days, the forecast has predicted rain and, for the return trip on the coast, headwinds. I’ve been meaning to write a little something on the blessing and curse of modern weather forecasting for the modern bicycle rider. By which I mean: The blessing is that the sort of forecasting that’s possible today, along with tools like Doppler radar and satellite water-vapor imagery, can give you a pretty clear idea of what you’re riding into and when; the curse is that you become the prisoner of a prospective and freely revised reality.
Weather forecasting is highly model driven, meaning that a bunch of unimaginably fast and powerful computers are applying sophisticated mathematical models to the wealth of weather data pouring in from all over the globe; when the machines finish their model-assisted number crunching, they spit out a picture of the way the world will look in 12 and 24 and 48 hours and so on. Then forecasters take these visions of the world as the models predict it and try to turn them into forecasts. Except: Sometimes the forecasters are confronted with two or three or six conflicting, or at least significantly varying, takes on what tomorrow and the day after and the day after that, ad infinitum, will look like. Then the humans have to do something that is a cross between highly educated guesswork and astrology: often, based on observations about which models have “verified” recently, they’ll make a prediction based on a compromise reading of models or just lean on the model that seems the most trustworthy in a given set of circumstances.
The curse, more specifically, is that we can all look at the developing forecasts, read the forecasters’ reasoning, even consult the raw data if we think we can handle that. Which means, in the end, we don’t get a minute’s rest thinking about whether it will rain, how much it will rain, how awful the headwinds will be out on the road. On balance, it seems like it would be simpler, and much more peaceful for the soul, to just look out the window before you get on your bike. But that would be much too simple and would fail to make the best use of our high-speed Net connections.
Time for bed now, right after I check the forecast and the radar again.
Technorati Tags: berkeley, cycling, randonneuring, san francisco, weather
Dude, great post. I came to it right after checking out the AccuWeather 6-10 day for Napa, hoping to get a sense of what Ma Nature will give us on Marathon Day eight days from now. I’ve been checking the forecast discussion at the NWS, too, of course — and was buoyed to see this morning’s note that the GFS keeps things dry “INTO THURSDAY MORNING BEFORE RIDGING BEGINS IN ERNEST AND WINDS TURN MORE TO THE NORTH AND DRYING TAKES PLACE.” Of course, there’s always another model… “WILL WAIT TO SEE THE 12Z EURO BEFORE COMMITTING TO HOW DRY AND HOW MUCH WARMING WE MAY SEE BY WEEKS END AND INTO NEXT WEEKEND.”
Well alright. Have a good ride and be safe.