The U.S. State Department issued a worldwide travel warning Friday morning for Americans, as a result of possible threats from Al Qaeda. It will also temporarily close multiple consulates and embassies in countries located in the Middle East and North Africa starting Sunday, August 4.

From the memo issued by the State Department:

The Department of State alerts U.S. citizens to the continued potential for terrorist attacks, particularly in the Middle East and North Africa, and possibly occurring in or emanating from the Arabian Peninsula. Current information suggests that al-Qaeda and affiliated organizations continue to plan terrorist attacks both in the region and beyond, and that they may focus efforts to conduct attacks in the period between now and the end of August.

The travel alert was global, but U.S. actions in response appear focused primarily on the regions in which the embassies and consulates are set to close. The threat, according to a source who spoke with NBC, seems to be coming from Al Qaeda's affiliate in Yemen, a country that intelligence agencies have been monitoring with increasing concern.

"This is a higher-than-normal threat stream," according to a source who spoke with CNN, while another said that there has been "more than the usual chatter" regarding possible terrorist operations.

Here are the consulates and embassies set to close on Sunday: Algiers, Algeria, Sana'a, Yemen; Tel Aviv, Israel; Riyadh, Saudi Arabia; Dhaka, Bangladesh; Kuwait City, Kuwait; Ankara, Turkey; Muscat, Oman; Doha, Qatar; Cairo, Egypt; Kabul, Afghanistan; Baghdad, Iraq; Amman, Jordan; Abu Dhabi, United Arab Emirates; Manama, Bahrain; Tripoli, Libya; Nouakchott, Mauritania; and Doha, Qatar.

The travel alert expires August 31.

[CNN, NBC, State Dept.]