Hello Gordon, 

Thank you for reaching out to the EMG helpline. I'm sorry to hear about your trouble germinating carrot seeds. 

Seeds are typically viable for 2-5 years and germination temperatures are 45-85 degrees F. It sounds like you're OK with these two elements.

A key to carrot germination is keeping seeds moist until they have germinated (up to 3 weeks). It's possible that heavy rains could have impacted the seeds or they could have dried out between rains and watering. 

Carrots are also sensitive to compacted soil. They grow best on deep, loose, well-drained mineral or organic soils with good water-holding capacity and few physical obstructions, such as stones. Soils that crust easily after rain are unsuitable because seedlings will have trouble breaking through the surface. 

As for what to do now - If your soil condition is not compacted, you could try to plant a variety with a shorter maturity time now. It might also be possible to regularly water the seeds already planted in hopes of germination. 

I hope this information is helpful. Please feel to reach out if you have any additional comments or questions.