Is it snowing now at DC?

To answer your immediate question, as of 11:19am on Tuesday, it is not snowing. We are expecting the snow to start gradually during the next few hours, becoming heavy by this evening, and continuing into Wednesday morning. Most areas will get from 10-20", and that is on top of the 24-30" we already have.

Most transportation will indeed by canceled, or heavily delayed. Amtrak has a pretty good record of keeping their tracks open during snowstorms. If you absolutely have to go tomorrow, it's worth checking to see what Amtrak is doing:
http://www.amtrak.com

At 1:41 pm, I looked outside my office window in Arlington, Virginia, and I'm just across the bridge from the Georgetown area of DC. It's not snowing yet, but as soon as it does, I'm heading home. We are supposed to get another walloping on top of the couple feet we've already got.

Right now, Metrorail is almost fully functional (except for a few stations at the eastern end of the Blue Line) and Metrobus is running limited service on Snow Emergency Routes, but as the weather deteriorates, that will change.

If you can postpone your trip, it might not be a bad idea.

*sigh*

I have the same dilemma, I'm flying into DC Thursday morning and am worried that the town will be shut down because of the snow. Some airlines are waiving the cancellation fees for flights into the DC area this week because of the storms so you may want to check into that.

They already have 31+ inches and they are suppose to get at least a foot+ in the next 24-36 hours

The worst of the snow will be overnight tonight. I would assume your transit will be canceled and be happily surprised if it isn't.

you might have some trouble getting into DC tommorow, they are saying could be another 20+ inchs, and the airport is barely operational after the last storm so i wish you good luck but i dont think you we be able to get there, they will probably close the airport, im in michigan and its just starting to snow here, so its like the whole eastern part of the country, good luck hope you get to where ur going..