Last weekend, areas just outside of Boston received as much as a foot of snow. Since then, temperatures have remained below freezing, allowing plowed snow to accumulate in snowbanks and along roadsides. This week, much of that snow should melt. This afternoon and tonight Cambridge will experience one more snowstorm — the same one that has already caused thundersnow and ice throughout the Midwest. However, tomorrow the temperatures will rise into the 40s and remain above freezing for the rest of the week, with rain showers on Wednesday afternoon and Friday.