Idaho

OUR GEM: Drought and snowpack update for the Idaho Panhandle

Published

on



After a dry and mild fall, many were looking forward to an increase of moisture across North Idaho to lessen the drought impacts that have persisted for the last two years. Since last fall, the National Weather Service’s Climate Prediction Center has been advertising wetter-than-normal conditions for the winter season across the Inland NW with the arrival of La Niña.

Advertisement

The rounds of precipitation picked up in November and continued off and on through December and into early January. This precipitation has been beneficial and not excessive for this time of the year. With low soil moisture, much of the precipitation soaked into the thirsty ground and gave way to less runoff with only slight rises on area rivers and creeks. The snowpack got off to an early start at the higher elevations and soared above normal by late November which was a boon for area ski resorts during the holiday season. As temperatures remained mild, the higher elevations reaped the benefits of the snow, while lower elevations experienced more cold rain with sloppy snow that melted quickly. 

As of mid-January, the National Resources Conservation Service mountain snow water equivalent across the Idaho Panhandle ranged from 95% to 118% of normal, and these sites were primarily above 4,500 feet. Water year precipitation, which began Oct. 1, was roughly 80% to 90% of normal for the Panhandle mountains, while the lower elevations from Sandpoint to Coeur d’Alene and Moscow to Lewiston were already above normal for the water year precipitation. With the influx of precipitation, drought conditions have seen a gradual improvement since the start of the water year with Abnormally Dry to Moderate Drought remaining across the Idaho Panhandle in the U.S. Drought Monitor.

Now it appears we’ve moved into a January lull as the storm track shifted from the region and leaving dry and cold weather, although no need to sound the alarms yet. There are still several weeks of winter left and the long-range forecasts and outlooks lean toward more active, wet weather by early February accompanied by colder temperatures. This trend is favored to continue into March and should bode well for the return to snow for northern Idaho, especially the mountains. The median peak snowpack for the Idaho Panhandle is typically around April 1 before the runoff season kicks into gear. 

As for the spring runoff season, the Long Range Flood Outlook appears to mirror close to climatology. There is an elevated risk of higher flows on the mainstem rivers across the central Idaho Panhandle, including the Coeur d’Alene at Cataldo and the Palouse at Potlatch. This is dependent on how fast the snow melts and how wet the weather turns this spring. It’s slightly early yet the Northwest River Forecast Center’s Water Supply forecast is leaning toward below-normal values across the Idaho Panhandle, ranging from 70% to 90% of normal for the April to September 2025 period.

A La Niña Advisory is in effect, and this La Niña is anticipated to be short-lived and weak with conditions transitioning to ENSO-neutral during March-May 2025 (60% chance). The CPC Seasonal Outlook for March into May continues to lean toward wetter and cooler than normal conditions for northern Idaho as drought removal looks likely. Stay up to date on the latest weather forecasts and updates on the local NWS Spokane webpage at www.weather.gov/spokane.  

Advertisement

• • •

Robin Fox is a Service Hydrologist for the National Weather Service — Spokane.

The Our Gem Coeur d’Alene Lake Collaborative is a team of committed and passionate professionals working to preserve lake health and protect water quality by promoting community awareness of local water resources through education, outreach, and stewardship. Our Gem includes local experts from the University of Idaho — Idaho Water Resources Research Institute, Coeur d’Alene Tribe, Idaho Department of Environmental Quality, the Basin Environmental Improvement Project Commission, Kootenai Environmental Alliance. 



Source link

Advertisement

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Trending

Exit mobile version