What are good varieties of tomatoes for the Pacific Northwest?
When growing warm crops that need a vast amount of sun and hot temps to produce well, such as tomatoes, corn, squash, cucumbers, the best thing you can do is to wait for the soil to warm. It matters little what the air temperature is — if the soil is too cool, they will not grow into robust, healthy plants.
You might hold off putting tomatoes and warm crop plants in the ground until early to mid-June this year. By then, the soil will have warmed enough that the crop will not stop growing in the night. I have learned that plants put in that late catch up and may surpass the ones that folks have struggled to keep warm with various contraptions and hard work.
As for varieties, I would suggest you pick a variety that is listed as ripening with fewer days. These are in most cases tomatoes that do not grow huge fruits.
It stands to reason that gigantic fruits such as the beefsteak type would take a very long time to grow into the large size, then go through the ripening process. Some summers they may not have time to ripen.