Ground Delay Program: Evening Hotspots and Ground Stops

Published on Aug 19, 2025, 6:32 pm CDT

6 min read

Evening weather can flip U.S. flight operations from smooth to constrained in minutes. As storms pulse, the FAA's Air Traffic Control System Command Center, ATCSCC, adds or cancels initiatives that meter demand or pause traffic entirely. Expect rapid updates to routes and airport programs through the late evening on August 19, 2025, with advisories noting active reroutes and a continuing arrival metering program at Hartsfield-Jackson Atlanta International Airport, ATL. Here is how a ground delay program works, why a ground stop might appear, which airports tend to heat up by hour, and where to check before you leave.

Key Points

Why it matters: Late-day storms can trigger a ground delay program or ground stop with little notice.
Travel impact: Expect rolling reroutes and metering that shift connection times and gate pushes.
What's next: ATCSCC advisories update throughout the evening as weather moves and capacity changes.
Typical hotspots: New York area, Atlanta, Florida, Chicago, and Denver through the evening push.
Where to check: FAA NAS Status, OIS program tables, Advisories Database, and published reroutes.

Snapshot

A ground delay program, GDP, meters arrivals when projected demand exceeds an airport's acceptance rate, usually because of low ceilings, visibility, winds, or thunderstorms. The Command Center issues controlled departure slots, called EDCTs, to hold flights at origin until the arrival bank can be absorbed safely. A ground stop, GS, is more restrictive, pausing departures that meet specific criteria when immediate safety or capacity needs arise. On August 19, 2025, the FAA's operations plan highlights continued metering at Hartsfield-Jackson Atlanta International Airport, ATL, while listing potential initiatives for the New York terminals and Central Florida depending on storm evolution. ATCSCC also publishes route advisories and temporary closures to steer flows around convective weather. Always verify status before leaving for the airport.

Background

Traffic Flow Management uses layered tools to balance demand and capacity. GDPs manage arrival volume over a longer window, reducing airborne holding and smoothing banks. Ground stops address acute constraints such as rapidly building cells over final approach, runway closures, or unplanned outages. Severe Weather Avoidance Plan, SWAP, statements and collaborative tools like the Collaborative Trajectory Options Program, CTOP, support reroutes when sectors, oceanic tracks, or fixes are constrained. On a typical summer evening, pop-up cells can lower an Airport Acceptance Rate, AAR, by forcing single-runway operations or longer spacing on approach, which in turn triggers metering or a pause. Program status, reasons, and timing are published on the FAA's Operational Information System, OIS, and in ATCSCC advisories.

Latest Developments

ATCSCC updates GDPs, GS watches, and reroutes into the evening

The FAA's Current Operations Plan for August 19, 2025, notes an active ground delay program at Hartsfield-Jackson Atlanta International Airport, ATL, while watching possible GDP or GS actions for the New York terminals and Central Florida if storms persist. En-route constraints include thunderstorm impacts across multiple Air Route Traffic Control Centers and selected oceanic route closures as cells flare along the western Atlantic. ATCSCC has also published targeted reroutes to balance flows. For context on today's constraints and traveler takeaways, see our companion coverage, FAA Daily Air Traffic Report, August 19, 2025. Expect late-evening adjustments as lines pulse along approach corridors and as planners purge or extend programs to match capacity.

Hotspots by hour, Central Time

300 to 600 p.m. CT: New York area, John F. Kennedy International Airport, JFK, LaGuardia Airport, LGA, and Newark Liberty International Airport, EWR, often see wind-driven spacing, SWAP reroutes, or short GDPs when storms graze departure gates.
400 to 800 p.m. CT: Hartsfield-Jackson Atlanta International Airport, ATL, frequently meters arrivals as storms cross the terminal area, with knock-on impacts to Dallas Fort Worth International Airport, DFW, and Orlando International Airport, MCO, via reroute structures.
500 to 900 p.m. CT: Chicago O'Hare International Airport, ORD, and Denver International Airport, DEN, can shift to single-runway or de-rated operations in passing cells, prompting metering or brief stops. Timing varies by day, but these windows align with evening banks and storm climatology. Always treat them as risk ranges, not guarantees.

Where to check before you leave

Before you head to the airport, verify three things. First, review the NAS Status site for high-level flags and airport event cards. Second, open the OIS program tables to see active GDPs or GSes, including start times, scope, and reasons. Third, look at ATCSCC Advisories and Current Reroutes for SWAP statements, route closures, and EDCT implications. If your flight has an EDCT, plan to be at the gate early, since most operators target a narrow window around your slot. Pair those checks with your airline's app for push alerts on gate holds, rebooks, or connection protection.

Analysis

GDPs and GSes pop up because weather reshapes runway configurations, reduces usable airspace, or forces longer spacing on final. The moment an AAR drops below banked demand, planners choose the least disruptive tool that preserves safety. A GDP spreads pain predictably by holding departures at origin, which reduces airborne holding, keeps fuel burns reasonable, and protects arrival sequencing. A GS is reserved for sharper problems, such as cells parked on final, microbursts, sudden wind shifts, or runway closures, where demand must pause so crews can reset safely. Reroutes, via SWAP or CTOP, keep the system moving by diverting flows around constrained sectors or oceanic tracks, sometimes trading a modest mileage increase for schedule stability. For travelers, the practical implications are straightforward. If you see an EDCT in your airline app, your connection risk changes, and you should seek longer downline layovers on the same carrier. If a GS is in effect, expect holds at origin and possible misconnect protection from the airline once the stop lifts. Real-time checks help you decide whether to leave early, adjust ground transport, or request a protected connection.

Final Thoughts

Late-day storms and shifting winds will always make the evening push volatile. Understanding the difference between a ground stop and a ground delay program, and knowing the hotspots by hour, gives you an edge when weather threatens your plans. Build a little slack into connections, watch for EDCTs, and verify status on NAS Status, OIS, Advisories, and Current Reroutes before you roll to the airport. With that routine, you can travel smarter through the inevitable summer convective bumps and the next ground delay program.