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And be sure to leave some room in your suitcase for new items you will accumulate, such as souvenirs from your travels or coursework you want to keep.
Fall/Spring Clothes
The weather is similar to Cambridge, MA in September/May. England is generally rainy but lucky for you, Cambridge is the least rainy city. Expect to have sudden light rainfall but major showers are infrequent.
Temperature + rainfall averages: http://www.worldweatheronline.com/Cambridge-weather-averages/Cambridgeshire/GB.aspx
Winter Clothes
The winter weather in Cambridge, UK is similar to fall in Cambridge, MA: mild temperatures and occasionally damp and windy. Since colleges and academic departments are spread throughout the city, be prepared to spend a significant amount of time outside getting from one place to another. Some rooms, particularly, lecture halls aren't heated to the level you've grown accustomed to at MIT. Leave your biggest winter coat at home but pack lots of sweaters.
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