So far this year nearly 600 motor vehicles have been stolen in Lodi. The police say their research indicates that many vehicles are stolen when the weather cools and people warm up their cars before heading to work.
In fact last week when the temperature dipped, the thieves were ready according to police spokeswoman Jeanie Biskup.
"In one day we had three vehicles stolen due to warm-ups."
This week the police department launched a new program called "cat" for Combat Auto Theft.
Teams of volunteers drive through selected neighborhoods looking for unattended vehicles with the motor running.
"We have our police volunteers going up to the doors and asking people to come out and shut off their vehicles."
A spokesman for a national organization that monitors car thefts says everyone in Lodi has an interest in this issue because the number of stolen vehicles in a community affects insurance rates.
The central valley is considered a haven for thieves. In recent years Modesto and the Stockton-Lodi areas have been at the top of the list of cities with high rates of theft.