Schedule: a typical summer Saturday (the flights of Jul 25, 2026), re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.

UNITED · FLIGHT UA 521 SCHEDULED · TYPICAL SCHEDULE

Saturday, October 3 Today

UA 521 · PWM → IAH

departs 3:30 PM ET · arrives 7:00 PM CT

Forecast issued Sat 2:00 AM ET · 14h before departure

Arrive at IAH more than 15 minutes late?

35% chance · ±2 pts +2 pts · 24h

HOW SURE WE ARE Good. The odds now lean mostly on firmed-up weather forecasts.

How late will it get to IAH?

On time or early
64%
15–30 min late
16%
30 min–1 hour late
9%
1–2 hours late
7%
Over 2 hours late
4%
Cancelled
1%

Gate arrival compared with the scheduled arrival. The ranges add up to 100%.

What’s moving the odds

↑ Cloud base down to 1,300 ft forecast at IAH that day

↑ Arrivals into IAH at that hour are often late

↑ Later flights pick up delays from earlier in the day

↓ Mostly benign weather forecast at PWM

↓ Other factors

Weather at each end

PWM (origin) Gusts12 kt Ceiling7,000 ft Visibility10+ mi Precipnone

IAH (destination) Gusts18 kt Ceiling1,300 ft Visibility9 mi Precip0.17 in

How this resolves

Yes if the gate arrival is more than 15 minutes after the scheduled arrival. Cancelled or diverted flights resolve N/A.

Every question here is display only — there is no betting or money involved. Gate times come from the airline; a cancellation resolves only the “Cancelled?” question, and a diversion voids the delay questions.

UA 521 · PWM → IAH

Odds over time

How late will it get to IAH?