Wow. What a challenge. That is why we always prep and paint any exterior trim before we deliver it to our window jobsites.

The wood must be dry before painting. No exceptions. If not, the moisture will push the paint film off before spring arrives. Please don't attempt to paint damp lumber.

Yes, there are 35 degree paints but, even those have limitations. Super Paint by SW and Duration are two that qualify. Read the label and abide by it or the paint will fail. Tip: Duration is self priming. If you can get one coat on now, and one in the spring, that may be sufficient to prevent problems over the winter.

If left uncovered, and it gets wet, the pine will probably expand with the moisture, and split open during the winter months. It may also warp badly enough that it will need replaced in spring.

Michael

Thanks, Michael. The trim had to be custom cut on site because it was going over an old sill that was level on top (not slanted). Unusual application. We could have had it wrapped but decided not to as we couldn't get vinyl or aluminum to match the trim color of the house.

Today we had torrents of rain so now it's really wet. I'll wait for it to dry thoroughly and then get one coat of one of those paints you mentioned on it. It's all ground level work, at least!

Thanks again.

Update--the carpenter couldn't put the final trim on until the end of January due to Home Depot ordering the wrong size back door twice!

Fortunately, the unpainted pine held up really well all winter. No splits, no warping. I just put the first coat of primer on and will caulk tomorrow. Woohoo!