The San Joaquin Valley in California has been experiencing a warm winter so far this year. Chilling hours necessary for tree fruit production are the lowest they have been in more than ten years. Poor chilling during the fall and winter months tends to lead to poor fruit set and quality in the spring and summer. The University of California system measures the accumulated chill hours around the state. The season runs from November 1 to February 28. Hours are measured below 45 degrees to get the accumulated totals. The low hours accumulated so far are a concern to the tree fruit industry in California.