Depends on your route. It can be 60 or a blizzard.
What do you want to see? Ocean? Mountains?
Small towns? Wine and Beer?

Really just want to get there in one piece. Driving up California coast for ocean. Live in VT so plenty of mountains here. Would like to stop in Ashland and possibly Portland . Thanks!

We make this trip most every winter, including on the 13th and 14th of this month.

We go up 101 to avoid the boring stretches of I-5 and the likely ice or snow on that route.

This year we stopped at Brookings (Best Western Beachfront, with ocean view) and Cannon Beach. From Cannon Beach, we drove to Seattle via Raymond WA and Olympia.

The drives were 379 miles/7 hours, 412/7 hours, and 200/4 hours. It is quite beautiful most of the way with the redwoods and great ocean views along many stretches from Eureka north.

HTtY

I would not plan a trip up I-5 in Feb until the very last minute to see what the weather is. Snow/ice/closed road are all distinct possibilities. And chains - which are not allowed on some rental cars. (or the weather could be fine - but you won't know until a few days ahead).

htty's suggestion to drive up 101 is the only one that makes sense if you don't have date wiggle room.

Are you coming back to SF sometime? If you have 3 days why not take the Amtrak Coast Starlight? It leaves Emeryville late evening. By dawn you will have a view of snow capped Mt. Shasta.
Get off the train in Eugene Oregon for 24 hours and then take the next Coast Starlight to Seattle or Portland if you want a rental car to drive to SEA.
If you must drive, go up US101 to Crescent City for the first day. The next day go at least as far as Reedsport Oregon.
If the weather is good go over Rt. 38 to get back to I-5. Otherwise continue up 101 to Astoria and then east on US 30 crossing the Columbia at Longview to get on I-5 to Seattle.

I would make a last minute decision on driving route (if you're not taking the train, which is an idea worth considering)...if the weather is winter-mild on the entire route, I would recommend I-5 because either way it's still a long drive - this route is faster and very scenic and there are many places along the way to take brief side-trips...for any route, make sure to daily check on road conditions through sites like CalTrans and the Oregon/Washington equivalents...have fun!

"Live in VT so plenty of mountains here."

Nothing in Vermont compares with the peaks of the Cascades or the massiveness of the Sierra Nevada. We even have peaks in the Coastal Range higher than any mountain in Vermont. Mt. Shasta and Mt. Rainier are both over 14,000 feet high. In February though, the weather can be dicey and sticking to the coast might make the most sense. But, if you want to visit Ashland, you need to go inland.

Take I-5 to Ashland, first day, spend the night, head over to the coast via 199, glimpse the redwoods, then head North.
Stay in the Yachats to Cannon Beach realm, then head North
to 26, over to Portland, and up to Seattle.

bbqboy has it exactly right. You will need to drive north of Ashland to Grants Pass to pick up 199, and you will be heading southwest when your goal is to the north...but it is far and away the best route to get to the coast and see redwoods.

To drive San Francisco-Grants Pass-Yachats (via 199)-Cannon Beach-Portland-Seattle is an indirect route between San Francisco to Seattle. If the OP gets as far as Grants Pass, she is not likely to find adverse driving conditions on I-5 driving north, but she might find ice or snow on Highway 199 (going south).

HTtY

going up I-5 will not be such a great idea (or even possible) if there's a storm like the one a few weeks ago.

That's why I suggested you need to wait to see what the weather is. And if it IS crappy, you need to drop Ashland from your wish list . . .

We are in Ashland tonight, having left Sacramento around noon. (Actually we're in Medford; hotels in Ashland are overpriced and generally mediocre, but we had dinner there tonight.) Frankly Ashland is a little depressing in midwinter, nothing like the charm of the summer/tourist/festival season.

I-5 was fine; reasonably fast. There was roadside snow in the Siskiyous but the temperature never got below freezing, but there was enough roadside snow that it could have gone differently.

Between SF and Seattle, I-5 is around three to four driving hours shorter (tops) compared to my usual route (several dozen reps over the years) which is 101 to Reedsport, OR, then Oregon 38 over to I-5 near Drain, then I-5 the rest of the way. In fact, traffic getting out of the Bay Area over to I-5 can be awful, partly neutralizing whatever time advantage exists, compared to blasting over the Golden Gate and up 101.

In my opinion, those extra hours are more than worth it, in fact in winter it's not only less boring but offers more interesting places for stops and stopovers. Depending on when you leave SF, the first night can easily be in Eureka (allowing time for visits to some of the redwood groves, e.g. the Avenue of the Giants) or if you want quaint (moreso than Ashland, actually) spend the night in Ferndale, CA, just south of Eureka.

With short daylight hours, the next night can easily be in Eugene, again with plenty of time for stops along the Oregon coast en route. OR 38 is a treasure - scenic, reasonably quick. Seattle is a 5-hour drive from Eugene the next day, badda bing.

I just watched the Medford weather forecast. Don't be too surprised when you see the 2" of snow on the road in the morning. They are also calling for some strong winds that can cause whiteout conditions. Stay safe Guardyloo.

Thanks, but it's mid-40s and raining. The only (minor) concern will be the hilly bits between Grants Pass and Roseburg, but we're making a late-ish start (only shooting for Portland tonight - more friends) so we'll probably miss anything nasty during the day.

Are you sure you weren't seeing the forecast for Medford, MA? Definitely a snowy yucky day over there.

I watch the weather on KDRV 12. I'm glad it didn't get below 32 in town. Where I'm at on the east side of the Cascades it is 27 and snowing.
Make a stop at Powell's book store if it is raining in Portland.

Thanks for all the advice. I think I will skip Ashland and go up the coast. Because of the extra driving time I think I will skip Portland as well. What is the best route to go from Santa Cruz to Seattle. I am thinking about skipping San Francisco as well. Thanks again!

Head northeast on Calif. Hwy 17 from Santa Cruz to the junction with I-280 north, follow I-280 into San Francisco, where it becomes 19th Avenue, then Park Presidio Drive (Calif. Hwy 1 all the way.) It joins with US 101 at the Golden Gate Bridge (no toll northbound). Stay on US 101 all the way to Reedsport, Oregon, then follow Oregon 38 east to I-5. Take I-5 through Portland (you can use the I-205 bypass if you want, it doesn't make much difference except in rush hours) and over the Columbia into Washington. Then follow I-5 all the way into Seattle.

California 17 is a rather twisty 4-lane road with a lot of traffic; you can avoid it by taking California Hwy 1 through Half Moon Bay and Pacifica, but you can't avoid passing through SF on surface streets (trafficky but usually quick - 20 min. or so will get you through the city.)

101 is mostly divided highway (maybe 50-75 miles not) from SF to Arcata (north of Eureka) then mainly 2-lane road to Crescent City, then 2 lanes throughout Oregon. In February traffic will be negligible, but be careful passing in Oregon - turn signal handles are unused appendages for many Oregon drivers.

With a morning start in Santa Cruz, I'd look at somewhere around either Eureka or Crescent City for the first night, then maybe Eugene for the second night, then Seattle. Don't skip the opportunity to visit some of the Redwood groves between around Leggett and Crescent City. They're remarkable even in the drippy February weather.

Good decision to skip Ashland. The most mountainous roads are immediately north and south of Ashland and these are really big mountain roads, not like anything in Vermont. When it gets icy, they can be quite dangerous. Unless you're familiar with those roads or familiar with the kind of driving necessary, it's a good decision to skip it altogether.

The best way to get from Santa Cruz north is the just get on Highway 1 and go north all the way. If you take 17, then 280, you'll end up on surface streets in San Francisco, but the better surface streets is the one route using Highway 1 (19th Avenue). It's almost a straight shot up north and I've timed the trip many times, probably takes about 20 minutes to go through San Francisco that way, so it's not bad at all. Besides which, the drive is easy.

Just look at Google maps and you'll see how straight north you'll be driving on Highway 1 through San Francisco. There will only a couple of adjustments. At one point, Highway 1 will start going inland and join with I-280, which is a freeway. Keep going on I-280 until you see the signs for "Highway 1, Golden Gate Bridge", the exit to the surface streets will be on the LEFT. Once you're on the surface streets, stay in the left two lanes as there will be a huge left turn coming up. Once you make that left turn, all three lanes are OK and it's a straight shot north. The only other part to look out for is at the Golden Gate Park where the road winds around a bit, but just stay on it. It's not that hard to get through the Park.

The rest of the way to Seattle, just follow the recommendations of the others. Good advice all around from the others.

Have a safe trip!

What you will see on 101 is well worth skipping Ashland and Portland, as you said you plan to do.

The route I outlined for you earlier is mostly through great scenery and, in Oregon, some delightful towns. The same cannot be said of I-5.

You can shave off an hour by going over to I-5 at Newport, but then you would miss some sights you would regret missing if you knew they were there.

HTtY

Both I-280 and SR 1 end up hitting 19th Avenue at Park Merced. No big.

I would modify gardyloo's suggested route only to recommend using 405 instead of 205. Much shorter and well-signed. 205 takes you well east of downtown Portland.