Working as a ranger at Old Faithful was one of the thrills of my life. There’s no question that Old Faithful and the Upper Geyser Basin are icons of our National Park System. Working here gave me the opportunity to learn some of the individual personalities of the geysers.

One of my favorite shifts was called, Geyser Predict.  On that shift, we would be required to go out into the basin early, before the visitor center opened and predict when some of the more regular geysers where going to erupt.

Predicting geyser eruptions is not an exact science. Most predictions are based on when the previous eruption occurred. It’s statistics really. Some large geysers have equipment that measures the temperature in the run-off channels and by down loading that information, the rangers can see when the last eruption happened.

We would often get asked about how the weather affects geyser intervals. Does Old Faithful still erupt when it is -40 degrees outside? The answer is yes. The outside temperature doesn’t seem to have much effect on when a geyser will erupt.

But, some other aspects of weather may influence geyser activity. New studies by scientists at the U. S. Geological Survey seem to indicate that both long and short term wet and dry periods could influence geysers. The thinking is that geysers like Old faithful may have shorter intervals during wet periods. Aurum Geyser seems more active after a rain or hail storm.

Wind may also play a role for some geysers. It has long been thought that Daisy Geyser would have a longer interval on windy days. Beehive Geyser has a tendency to erupt early in the day; wind may also influence that trend. The direction of the wind seems to be an important factor.

If geysers interest you, check out the folks at the Geyser Observation and Study Association. They have many volunteers that work closely with the park’s rangers and geologists to help us keep statistics and understand these unique features. (www.gosa.org)

So, the next time you are fortunate enough to be waiting for a geyser to erupt, take notice of what else could be influencing that eruption. And remember, geysers are never late and geysers are never early and predictions are just predictions.