No matter where you're camping,
having the appropriate shelter during Winter months is crucial. I personally spent THREE YEARS camping in near freezing rain using the shelter I'm about to show you. It's much cheaper to build this then buy a tent, it's more comfortable, and it will last longer. More importantly, though, this shelter was designed for long duration camping in the rain.
Portland Oregon has the hardest and most challenging Winter months
for camping as it rains almost constantly and the temperature hangs right around 33 degrees; and believe me, 33 degrees and wet is by far worse than 15 degrees and dry.
To keep dry the shelter is built around a hammock, which keeps you up off the ground. Because I'm urban camping in the city park, my shelter is also made of camouflage, and I also designed it to quickly lay flat on the ground for additional stealth.