Spring Runoff Update for Star Valley

Spring Runoff Update for Star Valley

At the end of April after a record setting winter there was considerable concern that the Spring Runoff would result in flooding across Star Valley. Follows is the blog on the record Winter Snowfall.

Summary Of Star Valley Record Snowfall-Winter 2022-2023


While the runoff has resulted in low land flooding along the Salt River,  a warmer and drier than normal May appears to have blunted what could have been a major flooding event.  Following are the images of both the temperature and precipitation  departure  from average for Wyoming.


All of Wyoming has experienced near or above normal temperaures in May.

All but the eastern border region of Wyoming has had a drier than normal month of May.


Examining the SNOTEL sites shows the very favorable melt off pattern which has apparently  averted what could have been a major flooding event.


The Willow Creek SNOTEL shows that by late April the snowpack had quickly started the melting process.  In fact the Snow Water Equivalent  by the last week of May has decreased below the same date in 2022, which was a low snow pack year(even though May 2022 was unusually snowy and cool).  As of later part of April the snow pack was near the records level of Spring 2011 which had  a particularly high runoff and flooding.  However, the pattern change latter part of April has quickly accelerated the snow melt.


The Salt River Summit SNOTEL meltoff to zero has occured during May after reaching near record levels by the end of April.


As of Memorial Day it appears that the Salt and Grey Rivers could have reached their peak.  That could locally change in the next week or so if heavy showers occur.


Following are river stages on the Salt near Etna and the Greys near Alpine.



The Snake River reservoirs appear to be in excellent condition.  Palisades Reservoir is above 80%  and on its way to filling during the month of June.