The Internet is a cool place. You can find all sorts of information out there. I was looking for a live web cam of the Snoqualmie falls for today (no such luck, although I did find this great video from November 2008 which is probably representative for what is going on right now: [linky]) but I did find the river flow information.
Here is the link for the entire Snohomish River Basin (which includes the Snoqualmie River Basin) - http://www.nwd-wc.usace.army.mil/nws/hh/basins/snoh.html
But the interesting graph is this one. --> click on it.
The data is quite striking.
January 6 - 10:00am the flow over the falls amounted to approximately 800 cubic feet per second.
January 7 - 8:00am the flow over the falls amounted to approximately 14,717 cubic feet per second. That is an eighteen fold increase.
There is the distinct possibility of record flooding occuring in Western Washington over the next 24 hours. Floods suck.