Update: Significant snow likely Tues.-Wed.

By Dan Stillman

* Winter Storm Watch Tues.-Wed. for most of metro area (map) *

* Watch out for ice dams | E-mail this forecast to a friend *

* Measuring Snowmageddon's depth | NWS totals | CWG snow reports *

* Power outage maps for Dominion Electric | Pepco | BG&E *

* News, traffic & storm coverage: Local home page | Get There *

The snowy scene out there is stunning, but I know for a lot of people enough is enough. Like it or not, the reality is that the latest information this evening points to a moderate, if not major in some places, snowstorm Tuesday into Wednesday.

It's exciting news for snow fans who are no doubt giddy about the prospect of this winter becoming D.C.'s second snowiest on record (need only around 1 inch to surpass the current No. 2: 46.0" in 1995-96) or the snowiest on record (need about 9 inches to pass the current No. 1: 54.4" in 1898-99), but sobering for those still without power or still unable to get out of their neighborhood.

So, how much snow are we talking, and when?

The next storm: Precipitation, primarily snow as it looks now but maybe mixed with sleet at the start, is on track to arrive Tuesday afternoon or evening. Snow, or briefly a snow/sleet mix, may be on the light side at first before probably becoming moderate to heavy overnight into Wednesday.

At least 4 inches is looking like a decent bet, with 8 inches or more a possibility. Here are our accumulation probabilities, which are likely to change as the storm gets closer:

15%: Less than 2"

25%: 2-5"

35%: 5-8"

25%: 8"+

Before the storm: After a mostly clear and cold night tonight with lows in the mid-teens downtown, and low teens in the suburbs with some upper single digits in the coldest spots, temperatures struggle again tomorrow as they probably max out around 30-35. Cold again tomorrow night with lows mainly in the teens and clouds increasing overnight or toward morning. Under cloudy skies, Tuesday highs should make the low-to-mid 30s before precipitation arrives by afternoon or evening.

SchoolCast (Mon.) (D.C. schools, which earlier announced a 2-hour delay, now indicates they will close)

FedCast (Mon.)