2018-04-28 Yellowstone Geysers-19 Published May 3, 2018 at 1600 × 1067 in 2018-04-28 Yellowstone Geysers-19 ← Previous / Next → Leah standing in front of the Grand Prismatic [hot] spring. It is a temperature of 147-188* F! Leah Sorensen in front of the Grand Prismatic [hot] spring. It is a temperature of 147-188* F!