Bring your slicker, Drew:
The forecast this Sunday is for temperatures in the mid-50s, a 70-percent chance of rain and 30-kph southwest winds.
Update [2006-3-31 17:40:34 by chris]: Like the Eurosport article cited by TC below, here's CyclingNews with some grim words for the peloton:
After several days of rain showers in Belgium, the famous Koppenberg, one of the 17 'walls' to ascend in Sunday's Ronde van Vlaanderen, has been reported to be unclimbable already. With local weather forecasts not seeing an end of the cool and damp conditions in Flanders at the moment, more rain showers are announced for the whole week-end, and temperatures will not rise above 13? on race day. Reconnoitring the route on Friday, Quick.Step's Filippo Pozzatto and Paolo Bettini, as well as FdJ's Philippe Gilbert got off their bikes when they arrived at the foot of the Koppenberg, which has a maximum gradient of 25 percent. The road being muddy, some cobbles loose, the pros complained about slipping rear wheels before stepping off their engines and being attended to by their service cars. But Belgian Sportwereld did report hard-headed tourists cycling up the Berg on Wednesday, calling Gilbert & Co. "cowards" for not doing it.