Happy Tuesday, Arlington! Here are five things you need to know today:

1. Weather: Expect plenty of sun today.High temperatures could reach 81 degrees with an overnight low of 64 degrees.

2. In case you missed it: Several Arlingtonians came out to donate blood Wednesday, hoping to meet the demands of a critically low blood shortage nationwide. The Red Cross has issued an appeal for blood donors this summer. In a statement, officials said the demand for blood produts remains steady, but donations this summer are the lowest in more than a decade. 

3. Right turn only: Starting today, July 15, the entry onto Massachusetts Avenue from Water Street and Peg Spengler Way at Robbins Library will be right turn only to improve safety around the library. Some parking will also be limited on Massachusetts Avenue by the library entrance. These changes will be part of a six-month trial period.

4. For the troops: Barrett & Company Real Estate is collecting donations of peanut butter, jelly and Marshmallow Fluff for Operation American Soldier. Small plastic jars can be dropped off at the Barrett & Company offices in Concord, Lincoln and Carlisle Centers.

5. This day in history: From History.com, "During a live television and radio broadcast, President Richard Nixon stuns the nation by announcing that he will visit communist China the following year. The statement marked a dramatic turning point in U.S.-China relations, as well as a major shift in American foreign policy."