Follow live updates as flight reductions begin today at 40 high-traffic airports in what officials have described as a "proactive" effort to alleviate pressure points.

As many as 1,800 flights could be affected on Friday alone, according to Cirium, an aviation-data provider. The final figure will depend on which airports are targeted. The FAA estimates that it handles an average of more than 44,000 flights a day.

Beginning next week, daytime rocket launches are all officially scrubbed thanks to the government shutdown.

American Airlines said that the 4% reduction will mean 220 canceled flights per day. The vast majority of impacted American Airlines flights are regional, and there’ll be no impact to international flights including Mexico, Canada and the Caribbean, CEO David Seymour said in a letter to employees. Further hub-to-hub routes impact will be minimized.

UPDATE: 3:40 p.m.: Austin-Bergstrom International Airport announced the FAA had lifted its ground delay as of 3:34 p.m. However, George Bush Intercontinental and Houston Hobby are both seeing ground delays of 46 minutes and 2 hours 46 minutes respectively, according to the FAA.

The federal government shutdown, now in its 38th day, prompted the Federal Aviation Administration to issue a temporary emergency order Thursday prohibiting commercial rocket launches from occurring during “peak hours” of air traffic.

Only two flights have been canceled so far at McGhee Tyson on Nov. 7. Knoxville, so far, has avoided the brunt of the government shutdown impacts on airports. Unlike other Tennessee airports, like Nashville International Airport, long security lines and delays have been minimal.

The Federal Aviation Administration (FAA) issued an emergency order restricting air carrier operations at 40 airports, which could impact travelers going to and from Erie International Airport. That list includes airports in Tampa,