Anyone packing for a trip to Tel Aviv should take climate into consideration. Winters begin around the middle of November and end in April at the very latest. They are also far milder than those of much of Europe and the U.S. Even in the North of the country, winter rainfall occurs fewer than 70 days a year - less, the farther south one travels. On sunny winter days people go to the beach, and there are quite a number who swim all the year round. All in all, the climate is really quite fine. Even in winter it rarely rains for an entire day and there is always intermittent fine weather, with the sun shining more often than not - ideal conditions for walking about and exploring the city most of the time, or going for an excursion out of town. Nevertheless, when traveling to Israel in winter it would be advisable to take along rainwear and warm clothing. During the summer, temperatures will usually range between 280-400 C.
Other clothing tips: a practical head covering for touring under the sun and for visiting holy places. Modest clothing for the holy places, too; shorts and sleeveless dresses just won't do. For men, unless there's a business element to your trip, it's doubtful that you'll ever feel the need to wear a tie.
And don't worry that you'll overlook something. Israel has earned a reputation as one of the world's fasting developing fashion centers, and any item of dress you may need - or just want - is sure to be available at a decent price, and clothing in sizes that are the same as in Europe.