Crabgrass in Western WA. lawn - Help!!

So, we live on 11 acres, built our house here on a former hayfield 14 years ago. Finally, we put up decorative fencing to establish what was lawn and ornamental, and what was hayfield and pasture for our horses. After construction they just leveled the ground around the house, and left. Ambient grasses were pretty in the spring, and were good enough. But for the last 4 years or so, the crabgrass has slowly but surely edged out the desirable grasses. Time for the first seed, I assume, and for a pre-emergent crabgrass killer. But with our sometimes mild winters, we aren't assured a deep freeze. I read somewhere about using this crabgrass killer both in fall and spring, if you had mild winter, but of course, I can't find that info again. It's not on the bag according to region, and says put on in the spring.

Also, should I drag a rake through before mowing again, to get the runners up. It's Sept 1st, we just had a soaking rain last week, and I noticed the brown crabgrass is sprouting and turning green again.......drat!

Any help is most appreciated!

Check with your extension office and get it identified and find the best way to get rid of it.
WSU has information also.