You have to feel for the folks in Sterling this morning. This is the kind of complex and difficult forecast that triggers migraines.

Cold air has been pushing into the region since we touched 50 degrees at The Sun yesterday afternoon. There's also warmer, wetter air moving up from the southwest, overriding the cold layer. It's colder still farther west, and at higher elevations. So what falls from the sky today depends entirely on where you are and how the cold air, warmer air, moisture and temperatures interact in three dimensions. It's no day for amateurs at Sterling.

UPDATE AT 4 P.M.: Temperature has reached 32 at The Sun, 33 at BWI. Here are some regional icing reports. Earlier post resumes below.

The steady temperature slide has gotten us to 36 degrees this morning here, and 34 at BWI. So far. That's why forecasters are still warning about the possibilities for sleet and freezing rain today north and west of Baltimore. That's before the colder air at the surface begins to erode and we go back to all rain late today. South and east of the city there's only rain in the forecast.

Eventually, the warmer air above the colder surface layer - and the rain it's dropping through that colder air - will overwhelm the cold and plain rain will prevail. And they expect plenty of it once it gets rolling.

Radar suggests there is lots more moisture to our south, and that's expected to move our way before this day is through. As much as an inch or two of rain is possible and the rain picks up later today and tonight. The rain will continue tomorrow, with another half- to three-quarters-of-an-inch in the cards.

Sunshine returns on Thursday and Friday, with colder, windier conditions. Another cold front (with showers) on Saturday will usher in even colder weather, with sunshine and highs only in the 30s Sunday and Monday.

No snow in sight for Baltimore. Total for the season so far (at BWI): 0.6 inch.