We brought raincoats and sweatshirts and the weather has been mostly in the 60s and gorgeous. We haven't worn any of the winter clothing we brought with us and I'm so glad I packed lightweight clothing for everyone because that's all we're wearing. The sweatshirts have been good for an extra layer in the early mornings and at night. The forecast for next week is much cooler and rainy though, so make sure to check before you pack.
It depends where you will be. Jerusalem and the North are chilly and you need a coat. You might consider a thinsulate packable jacket that covers lower temperatures with a heavy sweater underneath. Women in Jerusalem wear scarves and boots in the winter (not snow boots). When it's raining and blustery, the cold can be chilling. Layers make a lot of sense because in midday, the sun can come out and you'll be warm. Tel Aviv can be in the 50s or 60s and sometimes even higher. Points South like the Dead Sea or Eilat can be warmer still. Check weather.com for more information. This week looks a little warmer than usual with Jerusalem in the high 50s and 60s and Tel Aviv in the 70s. Looks like temps will come down later this week and there will be rain.