That depents on where she is going to... We have all the ranges here.
Last week while we were in short sleeves two hours drive car to the mountains they were getting pretty cold.
If she goes to the east or south coast is really mild weather. The north coast is a really raining place and cool...very beautiful too.
In the center of the peninsula is the tipycal continental weather. But for sure is not as cold as Chicago.
Keep in mind is the fall season and you never know.

Anna