Newark is in a thunderstorm ground stop with a GDP through midnight

The Northeast siege that fired at 8 AM is not clearing: Newark's morning ground stop held 725 flights with 145-minute average delays and converts to a ground delay program through midnight, Philadelphia opens a GDP at 2 PM averaging 141 minutes, the FAA's severe-weather avoidance plans put DC metro and Boston departures in the convective crosshairs this afternoon, Tropical Storm Bertha has strengthened to 60 mph with the warning expanded to the Terrebonne-Lafourche line, and American Airlines has a change-fee waiver covering nine East Coast airports through July 22.

Newark's ground stop is live and its GDP runs to midnight

Newark went through three ground stop iterations this morning as thunderstorms rebuilt over the terminal area. The first (FAA ADVZY 080, signed 9:52 AM ET) held 725 flights with average delays of 145 minutes and a maximum of 247, departing from Cleveland Center only, with the notation "NO ROUTE" meaning no available routing into the airport at all. The ground stop was re-issued twice (ADVZY 101 and 105, the latter signed 11:02 AM ET) with the departure scope expanded to the first tier of centers (Washington, New York, Cleveland, and Boston), and it converts to a ground delay program running from noon to midnight ET. The extension probability is MEDIUM. The cause is thunderstorms in the terminal area and along approach routes. This continues the disruption covered at the 8 AM window three hours ago, when LaGuardia and Newark first went into ground stops.

Philadelphia opens a ground delay program for this afternoon

Philadelphia opened a ground delay program (FAA ADVZY 103, signed 11:00 AM ET) for arrivals from 2 PM to midnight ET, with a maximum delay of 234 minutes and an average of 141 minutes. The program rate starts at 24 arrivals per hour. A separate arrival delay advisory (ADVZY 106, signed 11:06 AM ET) warns of up to 30 minutes of airborne holding into PHL from noon through midnight due to thunderstorms. This is the first Philadelphia ground delay program of this Northeast siege and marks the disruption spreading south from the New York metros.

The storm wave is rolling toward DC and Boston

The FAA issued severe-weather avoidance plan advisories for both Washington Center (ADVZY 100) and Boston Center (ADVZY 085) this morning, signaling the convective wave is moving from the New York metros toward the DC metros and Boston through the afternoon and evening. The Washington Center SWAP, signed at 10:20 AM ET, states that DC metro departures may experience delays due to weather, with isolated to scattered thunderstorms forecast across Virginia and the Delmarva through tonight, heaviest between 3 PM and 6 PM ET. The Boston Center SWAP, signed at 10:01 AM ET, forecasts thunderstorms across the Northeast from Washington Center through Boston Center, the New York metros, and across New York State, beginning at 11 AM ET and continuing past 11 PM. En route reroutes are already firing: a SERMN North reroute (ADVZY 107) forces New York departures to Midwest destinations onto alternate routing through 3 PM, and a Southeast to O'Hare reroute (ADVZY 077) does the same for Southeast-to-Chicago flights through 1 PM.

Tropical Storm Bertha strengthens to 60 mph

NHC Advisory #9 (10 AM CDT, 11 AM ET) found Bertha has strengthened to 60 mph sustained winds with a pressure of 995 mb, up from 50 mph at the 8 AM advisory. Air Force Hurricane Hunters detected the increase, and a NOAA buoy south-southeast of Pensacola reported 49 mph sustained winds with a 54 mph gust. Bertha is centered at 29.3N 86.3W, about 70 miles south-southwest of Panama City and 145 miles southeast of Mobile, moving north-northwest at 3 mph. The tropical storm warning was expanded westward to the Terrebonne/Lafourche Parish line in Louisiana, and the watch was extended westward to the Vermilion/Cameron Parish line. The storm surge watch was discontinued and replaced by a Coastal Flood Warning for southeastern Louisiana and Mississippi. Tropical storm conditions are expected along the northern Gulf coast by late today into Wednesday, with possible conditions in the Louisiana watch area by Wednesday. Bertha is forecast to move near or along the northern Gulf coast over the next several days, approaching southern Louisiana on Wednesday before weakening to a tropical depression on Thursday. No Gulf Coast airport ground stops have been issued yet. (ABC News, WAFB Baton Rouge)

Airline waivers: American covers nine East Coast airports

American Airlines has a change-fee waiver current as of July 21 covering nine East Coast airports: BWI, BOS, JFK, LGA, EWR, PHL, IAD, DCA, and HPN. Tickets must have been bought by July 19, travel is July 20 through 22, rebooking by July 22, and travel completed by July 24. Delta has a Northeast U.S. inclement weather advisory covering the same airport set (BOS, BWI, DCA, EWR, HPN, IAD, JFK, LGA, PHL), posted July 20. No Bertha-specific Gulf Coast waiver has been issued by any carrier yet. Based on the Tropical Storm Arthur playbook from June, American, Delta, Southwest, and United would be expected to issue Gulf Coast waivers covering Pensacola, Panama City, Mobile, Gulfport, and New Orleans once tropical storm conditions reach those airports late today or Wednesday.