The 2024-25 water year that began Oct. 1 started on a positive note in Utah’s valleys and mountains — and the region surrounding Moab had a particularly good month, according to Jordan Clayton of the Natural Resources Conservation Service’s Utah office.
In the valleys
“Precipitation was 125% of normal for the month of October, driven up by impressive totals in the Uinta Basin and in southeastern Utah,” wrote Clayton in his monthly report.
Statewide soil moisture at Utah’s SCAN sites ended the month below normal at 35% of saturation, roughly the same as last year at this time, wrote Clayton.
“The statewide value glosses over important geographic differences, however,” he said. “Soils are particularly dry in the northern and western regions of the state, as well as the St. George area.
“Conversely, soil moisture levels in the Uinta Basin bounced dramatically from record-dry in early October to around the bottom 30th percentile following the mid-October storms,” he continued. “Soil temperatures are much colder than normal for this time of year in the St. George region, and cool but closer to normal elsewhere.”
In the mountains
While Utah’s mountains received more precipitation than its valleys for the month of October (2.1″ versus 1.0″), when compared to the typical amount that Utah receives for the month, the mountain areas had a lower percent of normal precipitation than the state’s valley locations (90% versus 125% of median), wrote Clayton. He cautioned that we shouldn’t put too much stock in early snowpack.
“Some of that precipitation was snow, and while we’re always excited for the snowpack season (the mountains look lovely!) we opted to not include snowpack percent of normal values in this report since the normals for this time of year are so minimal that any accumulation amount relative to those small numbers tends to blow up the percentages and isn’t meaningful,” he wrote.
“We also want to caution Utahns to remember that last winter’s snowpack started slow but ended above normal and many other recent years have started strong but then flatlined in January with the presence of blocking atmospheric high pressure systems,” he continued. “Long story short: we welcome the snow but will wait to get too excited about it until much later in the season.”
Utah’s statewide soil moisture levels are hovering close to the bottom 10th percentile of observations, which is unfortunate and may impact runoff efficiency this coming snowmelt season, he said. “If we examine the soil moisture story by depth, the surficial and middle portions of the soil column (2″ and 8″ depths) improved markedly from the mid-October precipitation events. Deeper portions of the soil column (20″ depth) have retained below normal soil moisture levels and are less likely to make significant gains before this winter sets in.”
Reservoirs
Utah’s statewide reservoir storage is at 71% of capacity, which is 3% lower than last year’s Nov. 1 value. Water Availability Indices (WAIs) for Utah basins combine current reservoir conditions with observed streamflow for each region. WAIs are in the top 20th percentile for three of Utah’s 18 major basins (Ogden, Price, and Joe’s Valley) and well below normal for the Blacks Fork, Smiths Fork, Lower Sevier, and Virgin River watersheds.
The Water Availability Index percentile is 74% for Moab.
