Predictions are shown in Mountain Time.
Eruptions cannot be predicted with absolute certainty and estimates are derived from user reports.
GeyserPrediction
RiversideGeyserTimes 18:18 ± 25 minutes
RiversideNPS 18:20 ± 45 minutes
GrandNPS 19:45 ± 90 minutes
CastleNPS May 1 @ 08:45 ± 45 minutes
CastleGeyserTimes May 1 @ 10:01 ± 1 hour
DaisyGeyserTimes 19:04 ± 15 minutes
Old FaithfulGeyserTimes 19:47 ± 13 minutes
GrandGeyserTimes May 1 @ 02:15 ± 105 minutes

Predictions courtesy of:

GeyserTimes GeyserTimes
NPS National Park Service

(*) Prediction derived from double interval