As ice and snow once again socks the Southeast and makes its way northward, thousands of flights are being canceled or delayed, leaving travelers around the country stranded and unsure of when they will be able to fly again.

According to the latest data from FlightAware.com, 3,259 flights had already been canceled at U.S. airports by 12:30 p.m. ET today, with 4,039 flights delayed.

The two airports most directly impacted by the weather are Hartsfield-Jackson in Atlanta — the world’s busiest airport in terms of passenger traffic and Delta’s largest hub airport — and Charlotte/Douglas in Charlotte, NC, the home hub for US Airways.

As of right now, 832 flights out of ATL had been canceled today, with 807 incoming flights called off. In Charlotte, 392 outbound flights have been canceled, along with 408 inbound flights.

So not surprisingly, Delta and US Airways are among the airlines with the most cancelations, with 1,199 and 216 flights canceled, respectively.

Passengers booked to travel to the Southeast, Mid-Atlantic or Northeast in the coming days should check with their carrier now to see what flights are being canceled and what, if any rescheduling relief is being offered to impacted customers.

Delta’s website says travel booked through Feb. 13 to these Southeast cities — Asheville, NC; Atlanta; Charlotte, NC; Greensboro, NC; Greenville, SC; Huntsville, AL; Norfolk, VA; Raleigh, NC — can be rescheduled without a change fee, so long as the rebooked flight departs no later than Feb. 17.

For travel scheduled on Delta to these Northeast cities on Feb. 13 or Feb. 14 — Allentown, PA; Baltimore; Bangor, ME; Boston; Harrisburg, PA; Hartford, CT; Manchester, NH; New York JFK; New York LaGuardia; Newark; Newburgh, NY; Philadelphia; Portland, ME; Providence, RI; Washington Dulles; Washington Reagan National; White Plains, NY — can rebook without a change fee if the rescheduled flight departs no later than Feb. 19.

US Airways is allowing passengers with travel booked in the coming days to reschedule, depending on the date of travel and the destination city.

US Airways passengers scheduled to fly to any of these Southeast airports — Birmingham, AL ; Huntsville, AL ; Atlanta, GA ; Augusta, GA ; Salisbury, MD ; Asheville, NC ; Charlotte, NC ; Fayetteville, NC ; Greensboro, NC ; Greenville, NC ; Jacksonville, NC ; New Bern, NC ; Raleigh/Durham, NC ; Wilmington, NC ; Charleston, SC ; Columbia, SC ; Florence, SC ; Greenville, SC ; Johnson City, TN ; Knoxville, TN ; Charlottesville, VA ; Lynchburg, VA ; Newport News, VA ; Norfolk, VA ; Richmond, VA ; Roanoke, VA — today or tomorrow (2/12) are being given the option of rescheduling their trip to Feb. 13,14,15,16 or 17. No change fee should apply if the destination city remains the same, but the airline isn’t offering a firm guarantee that you won’t have to pay any additional money.

For US Airways travelers heading to these Northeast cities — Hartford, CT ; New Haven, CT ; Washington, DC (Dulles Int’l Airport) ; Washington, DC (Reagan National) ; Bangor, ME ; Portland, ME ; Baltimore, MD ; Boston, MA ; Manchester, NH ; Newark, NJ ; Albany, NY ; Binghamton, NY ; Islip, NY ; New York, NY (JFK Airport) ; New York, NY (LaGuardia) ; White Plains, NY ; Allentown, PA ; Harrisburg, PA ; Philadelphia, PA ; Scranton, PA ; State College, PA ; Williamsport, PA ; Providence, RI — on Feb. 13 or Feb. 14, the airline is making the same vague no-change-fee offer to those willing to reschedule to Feb. 15,16,17,18 or 19.

Though American Airlines is now merged with US Airways, there is slightly different info on its website.

American is waiving change fee once (so don’t expect to make multiple revisions to your itinerary without being charged a fee for people heading to these Southeast cities through Feb. 13 — Asheville/Hendersonville, NC; Atlanta, GA; Augusta, GA; Birmingham, AL; Charlotte, NC; Charlottesville, VA; Columbia, SC; Fayetteville, NC; Florence, SC; Greensboro/Highpoint, NC; Greenville/Spartanburg, SC; Greenville, NC; Huntsville, AL; Jacksonville, NC; Knoxville, TN; Lynchburg, VA; New Bern, NC; Newport News, VA; Norfolk, VA; Raleigh / Durham, NC; Richmond, VA; Roanoke, VA; Salisbury, MD; Tri City, TN; Wilmington, NC.

The same policy applies to travel booked to these Northeast destinations on Feb. 13-14 — Albany, NY; Allentown / Bethlehem, PA; Baltimore, MD; Bangor, ME; Binghamton, NY; Boston; Harrisburg, PA; Hartford Springfield, CT; Islip, NY; Manchester, NH; Newark; New Haven, CT; New York LaGuardia; New York JFK; Philadelphia; Providence, RI; Portland, ME; Scranton/Wilkes Barre, PA; State College University Park, PA; Washington Dulles; Washington Reagan Nat’l; Westchester County, NY; Williamsport, PA.

Here is info from the Southwest website:
Cities eligible for flexible accommodations Wednesday, February 12:
Atlanta (ATL)
Birmingham (BHM)
Charlotte (CLT)
Greenville/Spartanburg (GSP)
Jackson (JAN)
Nashville (BNA)
Raleigh/Durham (RDU)

Cities eligible for flexible accommodations Wednesday February 12 and Thursday, February 13:
Baltimore (BWI)
Charleston (CHS)
Norfolk (ORF)
Richmond (RIC)
Washington Dulles (IAD)
Washington Reagan National (DCA)

Cities eligible for flexible accommodations Thursday, February 13 and Friday, February 14:
Albany (ALB)
Boston (BOS)
Hartford (BDL)
Long Island/Islip (ISP)
Manchester (MHT)
New York (LaGuardia) (LGA)
Newark (EWR)
Philadelphia (PHL)
Portland (PWM)
Providence (PVD)

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