Henry’s Fork, March 28th, 2023

Here are Dr. Rob Van Kirk’s Snow-Water Equivalent (SWE) report headlines for the Henry’s Fork drainage today, March 28th.

Headlines

• Mean temperature yesterday was 13 degrees F below average, extending what has been a very cold winter into spring. Precipitation was light yesterday, but after updating data, the water-year total is 112% of average, a little higher than I reported yesterday. Snow water equivalent (SWE) stayed at 119% of average for the date and 109% of the average seasonal peak.

There is no end to cold, wet weather in sight. The latest 7-day quantitative forecast is now calling for widespread precipitation exceeding 0.75 inch over even the driest parts of the watershed, with up to 3 inches of water equivalent at the highest elevations. Below-average temperatures are expected to continue well into the month of April, with high confidence in that outlook.

At an outflow of 250 cfs, Island Park Reservoir is 86% full, compared with 82% full on average. The three reservoirs in the Henry’s Fork watershed are 88% full, compared with 86% full on average.

Rob Van Kirk, Ph.D.

Senior Scientist

Henry’s Fork Foundation

P.O. Box 550

Ashton, ID 83420

208-881-3407 CELL