Hmm, I don't have any
experience in zone 3/4, but that sure sounds like it would be too early. Peas can't germinate when the soil is that cold and they can become vulnerable to a multitude of pests once they start to soak up water- especially rodents and birds. I would wait till the soil warms a bit or plant in trays under
lights.
Here in western Oregon, we've had extremely wet and cold weather for the past 2 months- lots of flooding in low-lying areas. I direct-seeded peas in my girlfriend's garden during a brief lull in the cold rain a month ago and it was a big mistake- too early. I planted my own peas (Sugar Magnolia) in trays under lights a few weeks ago because the rodent and bird pressure here is extreme and they completely wiped out my entire crop last year. I'm going to wait till the soil warms up, the sun comes out and the peas get about 2 feet tall before I transplant. I'm determined to get peas this year!