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.

SOUTHWEST · FLIGHT WN 3891 SCHEDULED · TYPICAL SCHEDULE

Thursday, October 1 Tomorrow

WN 3891 · STL → BOS

departs 9:55 AM CT · arrives 1:30 PM ET

Forecast issued Wed 1:00 PM ET · 22h before departure

WN 3891 isn’t flying STL → BOS on Thu, Oct 1

This listing came from a typical schedule. According to the FAA, WN 3891 flies these legs that day:

SLC → SJC · 11:00 AM · scheduled