How reliable is Antonio B. Won Pat International Airport?
Flights from GUM departed within 15 minutes of schedule in 90% of 4,456 flights in official BTS history — and weather is calmest in Jun. Here’s the full picture before you book.
Reliability score
on-time, cancellations & delays
Weather favorability
year-round climate
Origin-airport operations
What the departure punctuality at GUM looks like
On-time departures
across 4,456 flights
Source: BTS Airport Operations · data through 2026-06-25. Role-specific BTS departure history; advisory context, not a guarantee for any flight.
Advertisement
Weather by month
When the weather works for you at Hagåtña
A calm-weather score (0–100) for each month from decades of airport observations — how often conditions disrupt flying, not temperature. Higher is calmer.
Calmest month
Calmest flying weather of the year · 98/100 favorability
Roughest month
Most disruptive — low visibility & fog, thunderstorms · 93/100 favorability
The read on GUM
What the numbers say about flying through Antonio B. Won Pat International Airport
Across official performance history, flights from Hagåtña left within 15 minutes of schedule about 90% of the time over 4,456 flights. That's one of the more dependable operational records you'll see. Pair it with a moderate cancellation rate of 1.5%. When a departure does run late, the typical delay is around 2 minutes.
On weather, Hagåtña is an unusually calm-weather airport year-round. June is the calmest stretch for flying, scoring 98 out of 100 for favorable conditions, while October is the most disruptive at 93, driven mainly by low visibility & fog and thunderstorms. The year is relatively steady, so no single month stands out as one to avoid on weather alone.
None of this guarantees your specific flight — it’s the backdrop. To turn it into a booking, score real flights to Hagåtña, read how we weigh it all in how the PlaneSane Score works, and brush up with how to pick a reliable flight and avoiding weather delays.
Common questions about GUM
- How reliable is Antonio B. Won Pat International Airport (GUM)?
- Flights from Hagåtña left within 15 minutes of schedule roughly 90% of the time across 4,456 flights of official history — one of the more dependable operational records you'll see. The cancellation rate runs about 1.5%. It's advisory context, not a guarantee for any single flight.
- What is the best month to fly from GUM for good weather?
- June has the calmest flying weather at Antonio B. Won Pat International Airport. October is the most disruptive, mainly from low visibility & fog and thunderstorms.
Planning a trip through Hagåtña?
Score real flights to and from GUM on reliability, weather, and connection safety — not just price.