Is the Marmot Chelsea warm enough for winter?

Yes for typical cold, wet city winters. The 700-fill down and waterproof shell handle damp cold well. In deep or prolonged freezing weather, the short length leaves your legs exposed.

Is it actually waterproof?

The softshell shell is described as waterproof, so it sheds rain and snow. Seams and the zip are the usual weak points in any softshell, so heavy downpours are still a test.

How does it compare with a long down parka?

It is lighter and easier to move in, and the down keeps warmth high for its weight. A long parka covers more of your legs and blocks more wind in extreme cold.

The coat itself. It is a single short down coat with a zip closure and softshell fabric.

Does it run true to size?

It is cut as a regular-length short coat meant to layer over a sweater. If you plan to wear bulky layers underneath, consider going up a size.

Can I machine wash it?

Down needs a gentle wash with a down-specific detergent and low-heat drying with dryer balls to restore loft. Follow the care label rather than regular laundry settings.