Apart from mentioning that an attack could occur in or emanate from the Arabian Peninsula, which is home to one of the most active al Qaida branches, the U.S. government gave no details as to the nature of this particular threat, or specifics on when or where such an attack might take place.
"They may focus efforts to conduct attacks in the period between now and the end of August," the State Department's travel alert said.
One date in particular - this Sunday, Aug. 4 - was mentioned in the State Department warning. All embassies that would've been open that day were ordered to close Sunday and perhaps longer. The edict affects embassies in Muslim countries, where Sunday is a workday, and coincides with a special night in the Islamic holy month of Ramadan.
However, analysts who study militant groups said, there's too little public information to draw conclusions as to the reasons for such a widespread shutdown of diplomatic operations. Such precautionary measures have become increasingly common in the aftermath of the Sept. 11 attacks that killed Ambassador Chris Stevens and three other Americans at U.S. posts in the eastern Libyan city of Benghazi.
In addition, mass demonstrations have turned to riots at U.S. missions in North Africa, still an extremely unstable region after the mass Arab Spring revolts ushered in an era of lawlessness and vigilantism.
"They're trying to be more proactive after what happened last year with Benghazi and Tunis and Cairo," said Aaron Zelin, who researches militants for the Washington Institute for Near East Policy and blogs about them at Jihadology.net.
Apart from "jubilation" over recent prison breaks that freed dozens of hardened jihadists, analysts said, militant forums haven't indicated that any major operation was afoot. However, the experts noted, any significant operations would be plotted face-to-face or via trusted couriers, not spilling over into Internet forums.
A similar "worldwide caution" to travelers last February says "these attacks may employ a wide variety of tactics including suicide operations, assassinations, kidnappings, hijackings, and bombings."
August is a popular month for U.S. flights making international trips. From 2003-2012, August had the second most international passenger flights on U.S. carriers, after July. There were 781,420 -- 9.1 percent of all international flights during the decade, according to the Bureau of Transportation statistics.
Twenty-one U.S. embassies and consulates around the world will be closed on Sunday as a "precautionary step," State Department spokesperson Marie Harf announced at a briefing Thursday.
- U.S. Embassy Abu Dhabi, United Arab Emirates
- U.S. Embassy Algiers, Algeria
- U.S. Embassy Amman, Jordan
- U.S. Embassy Baghdad, Iraq
- U.S. Embassy Cairo, Egypt
- U.S. Consulate Dhahran, Saudi Arabia
- U.S. Embassy Djibouti, Djibouti
- U.S. Embassy Dhaka, Bangladesh
- U.S. Embassy Doha, Qatar
- U.S. Consulate Dubai, United Arab Emirates
- U.S. Consulate Erbil, Iraq
- U.S. Consulate Jeddah, Saudi Arabia
- U.S. Embassy Kabul, Afghanistan
- U.S. Embassy Khartoum, Sudan
- U.S. Embassy Kuwait City, Kuwait
- U.S. Embassy Manama, Bahrain
- U.S. Embassy Muscat, Oman
- U.S. Embassy Nouakchott, Mauritania
- U.S. Embassy Riyadh, Saudi Arabia
- U.S. Embassy Sana'a, Yemen
- U.S. Embassy Tripoli, Libya
US/ISRAEL is planning another false flag OP!