Today 
Sun-loving tomatoes can suffer outdoors during spells of cold weather, with ideal temperatures from 18-24˚C and no lower than 13˚C. If it is too cold there might be poor pollination, curling of leaves and the fruits might be scarred, with holes.
Solution
Organic
Don't plant out tomatoes until temperatures in early summer have risen, especially at night. If in doubt, plant the tomatoes into generous-sized pots so the roots have plenty of room to grow and stand them outside on warm days, bringing them indoors when the temperatures drop. By late-June it's usually safe to leave them outside. Give them a sheltered, south-facing, sunny position. When temperatures dip again at the end of summer and early autumn, give tomato plants overnight protection with horticultural fleece, which should keep them safe until the first frosts.
