How reliable is Baltimore/Washington International Thurgood Marshall Airport?
Flights from BWI departed within 15 minutes of schedule in 73% of 562,922 flights in official BTS history — and weather is calmest in Aug. 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 BWI looks like
On-time departures
across 562,922 flights
Source: BTS Airport Operations · data through 2026-08-08. Role-specific BTS departure history; advisory context, not a guarantee for any flight.
Weather by month
When the weather works for you at Baltimore
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 · 95/100 favorability
Roughest month
Most disruptive — low visibility & fog, snow · 84/100 favorability
Connecting through BWI
How much layover you really need
Based on 67 sellable domestic itineraries seen through Google Flights. Median observed layover: 75 min.
Observed windows come from normalized SearchAPI / Google Flights itineraries. They are not official airport MCTs. We score every connecting itinerary against conservative connection floors.
The read on BWI
What the numbers say about flying through Baltimore/Washington International Thurgood Marshall Airport
Across official performance history, flights from Baltimore left within 15 minutes of schedule about 73% of the time over 562,922 flights. That's a middling record — neither a strength nor a red flag on its own. Pair it with a moderate cancellation rate of 1.7%. When a departure does run late, the typical delay is around 15 minutes.
On weather, Baltimore is an unusually calm-weather airport year-round. August is the calmest stretch for flying, scoring 95 out of 100 for favorable conditions, while January is the most disruptive at 84, driven mainly by low visibility & fog and snow. The year is relatively steady, so no single month stands out as one to avoid on weather alone.
If you're connecting through BWI, give yourself room. Real itineraries sold through BWI bottom out around 45 minutes for a domestic connection. Those are floors, not comfortable buffers — one inbound delay can erase them, so add margin when the connection matters.
None of this guarantees your specific flight — it’s the backdrop. To turn it into a booking, score real flights to Baltimore, 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 BWI
- How reliable is Baltimore/Washington International Thurgood Marshall Airport (BWI)?
- Flights from Baltimore left within 15 minutes of schedule roughly 73% of the time across 562,922 flights of official history — a middling record — neither a strength nor a red flag on its own. The cancellation rate runs about 1.7%. It's advisory context, not a guarantee for any single flight.
- What is the best month to fly from BWI for good weather?
- August has the calmest flying weather at Baltimore/Washington International Thurgood Marshall Airport. January is the most disruptive, mainly from low visibility & fog and snow.
- How much layover time do you need at BWI?
- Allow at least about 45 minutes for a domestic connection as a floor. These are minimums, not comfortable buffers — a single inbound delay can wipe them out, so add margin when you can.
Reliability guides
Planning a trip through Baltimore?
Score real flights to and from BWI on reliability, weather, and connection safety — not just price.