As promised, we're back to discuss the latest weather forecast (it's improving!) and provide some more specific delay estimates (they're shrinking!). For those who want to read our initial outlook, they can do so here: there's some commentary on NYC airspace conflicts, the expired slot usage waiver and queueing as it applies to air traffic. Somehow the New York Jets (the football team) even snuck their way into the first look.
High pressure builds in tonight and dominates for Thursday and Friday. We've linked to the same explainer on large scale weather patterns from the National Weather Service (tl;dr high pressure generally promotes fair weather while clouds and precipitation are associated with low pressure). The low pressure system we mentioned yesterday figures to be pushed far enough offshore that any rain will be confined to eastern Long Island; the NYC metro area is only liable to see an increase in cloud cover late Thursday afternoon. Fortunately, while clouds may thicken, they are not forecast to lower meaningfully and airport capacity should not be impacted.
With that said, we'll go ahead and revise our expected arrival rates upwards (and also plug our explainer on airport capacity). We think LGA will be able to deliver a 40 arrival rate and anticipate an arrival rate of at least 48 at JFK, though wouldn't be surprised to see 58. For those who read the first look, you may recall we did not highlight any demand overages at LGA or JFK - so while an increase in expected capacity is intrinsically a welcomed development, we weren't previously worried about delays at either airport. EWR is a more interesting case, where the improving weather forecast should at least yield a 40 arrival rate (up from a floor of 38 yesterday). To unlock their optimal arrival rate of 48, however, requires the availability of Runway 11/29: this is a dangerous wager. On account of its relatively short length, a conflict with Teterboro Airport (TEB) and dependencies on wind direction, Runway 11/29 is only used about 14% of the time (though a concerted effort is underway to increase its usage).
What does that mean for potential delays? If EWR is able to use Runway 11/29 and delivers a 48 rate, we don't expect any air traffic delays. If, however, 11/29 is unavailable and the arrival rate is set to 40, demand overages exist later in the day on both Thursday and Friday. The good news is the resulting delays are modeled to remain under 20 minutes on Thursday.
Local Hour (EWR) | Sched. Arrivals | Avg. Delay (mins) | Max. Delay (mins) |
4 p.m. Thu | 43 | 7 | 14 |
5 p.m. Thu | 40 | 6 | 14 |
6 p.m. Thu | 27 | 4 | 11 |
7 p.m. Thu | 44 | 7 | 17 |
8 p.m. Thu | 44 | 12 | 17 |
9 p.m. Thu | 29 | 4 | 17 |
We'd bet this level of delay falls short of requiring the type of initiative (e.g. ground stop or ground delay program) that appears on the FAA's handy status dashboard. Instead, we anticipate most of these delays will be absorbed in the air: don't be surprised if the last half hour or so that you're in-flight seems circuitous. A reasonable worst case scenario would be a short-lived ground stop, which keeps arrivals on the ground at their origin station, in the 7 p.m. hour.
Friday has the benefit of back-to-back hours during the early evening with excess supply, affording the airport a better opportunity to catch up. This longer recovery period serves to mitigate delays slightly relative to Thursday.
Local Hour (EWR) | Sched. Arrivals | Avg. Delay (mins) | Max. Delay (mins) |
4 p.m. Fri | 43 | 9 | 14 |
5 p.m. Fri | 36 | 5 | 13 |
6 p.m. Fri | 25 | 4 | 9 |
7 p.m. Fri | 45 | 6 | 14 |
8 p.m. Fri | 40 | 6 | 10 |
9 p.m. Fri | 22 | 1 | 8 |
So - that brings us to the same question as yesterday. Where does that leave marathon runners (and supporters) flying in on Thursday or Friday? Our answer from yesterday is largely intact. If you're flying into JFK or LGA, we don't foresee air traffic delays (of course, aircraft servicing, airline staffing, network effects, etc. can - and will - produce some delays). If you're arriving into EWR later in the day, you'd be well served to expect a delay of around 15 minutes. We think adjusting exceptions is all that's called for in this case, but that's easy for us to say - we don't need to worry about a tapering schedule. If you're anxious about these minor delays, airlines are thankfully offering increased booking flexibility. Specifically, change fees have been eliminated for most tickets, though a fare difference may apply. There's also been improvements to standby and same-day confirmed change policies; we've linked to respective policies for Alaska, American, Delta, JetBlue, Southwest and United.
How about the weather on Marathon day? We're happy to report the forecast remains dry for Sunday, as low pressure again tracks offshore. Good luck runners!