Schedule: a typical Thursday (the flights of Jul 30, 2026, re-dated). Real flights replace these once the FAA publishes them, usually about a day ahead.
DELTA · FLIGHT DL 1399
SCHEDULED · TYPICAL SCHEDULE
Thursday, October 1
DL 1399 · BOS → MIA
departs 7:05 AM ET · arrives 10:35 AM ET
Forecast issued Tue 7:00 PM ET · 36h before departure
Watch this flight
Other days
Today 18%
Wed 9/30 18%
Thu 10/1
Fri 10/2 16%
Sat 10/3 11%
Sun 10/4 11%
Mon 10/5 11%
Odds over time
Arrive at MIA more than 15 minutes late?
15%
chance · ±1 pts
−1 pt · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
15%
Leave 15+ late
6%
Arrive 1h+ late
5%
Cancelled
2%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
10%
20%
30%
40%
2.8d
2d
Now
1d
12h
6h
Departs
Lands
Arrive at MIA more than 15 minutes late?
Calm-weather odds: 7% · changed −1 pt in 24h
−1 pt
15%
Yes 15%
No 85%
Leave BOS more than 15 minutes late?
Calm-weather odds: 5% · changed +1 pt in 24h
+1 pt
6%
Yes 6%
No 94%
Arrive at MIA more than an hour late?
Calm-weather odds: 2% · changed +1 pt in 24h
+1 pt
5%
Yes 5%
No 95%
Cancelled?
Calm-weather odds: <1% · changed −1 pt in 24h
−1 pt
2%
Yes 2%
No 98%
How late will it get to MIA?
On time or early
83%
15–30 min late
8%
30 min–1 hour late
3%
1–2 hours late
2%
Over 2 hours late
2%
Cancelled
2%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
Gusts to 26 kt, 0.8 in of rain, thunderstorms forecast at MIA that day
↑
This flight has been late 15% of the time recently
↑
BOS is prone to delays
↓
Early flights usually leave on time
↓
Visibility down to 1 mi forecast at BOS that day
Weather at each end
BOS (origin)
Gusts 16 kt Ceiling none (clear) Visibility 1 mi Precip none
MIA (destination)
Gusts 26 kt Ceiling 2,600 ft Visibility 5 mi Precip 0.75 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.