Streamflow, Drought, and Water Supply Conditions
Water supply conditions as of 3/1/2019
From The montana water supply outlook report
Jefferson Basin: The snowpack is getting deep in the headwaters of the Jefferson! While out collecting snow course data this month it was difficult to make it across flat fields, much less up into the mountains to sample select snow courses dating back to the early 1960’s. What’s there at low elevation is pretty much bottomless due to the cold temperatures “rotting” the snow during the prolonged cold snaps this winter. Bloody Dick SNOTEL recorded the lowest density mid-winter snowpack it ever has just last week at 19%, while much of the state is around the 27% mark. Even if the cold temps have created a weak snowpack, it all melts the same come spring time, and there’s plenty of it. Snowfall was well above normal (>150%) to record setting across the basin during the month of February. SNOTEL sites in the Red Rock and Ruby River basins experienced their 1st or 2nd “snowiest” February on record, bringing some areas from well below normal on February 1st to near or above normal on March 1st. Not to be left out, the SNOTEL sites in the Tobacco Roots also experienced their 1st or 2nd snowiest February on record. While measurement locations in the Big Hole didn’t set records for the month, the above normal snowfall was enough to improve snowpack to near or above normal at most locations. It was quite the turnaround in southwest MT, where the ideal snow producing weather pattern occurred throughout the month. Streamflow forecasts issued on March 1st for the April 1st – July 31st period across the basin range from near average to above average depending on the sub-basin. With reservoir levels at 127% for this date, and favorable early season streamflow forecasts, the story for spring and summer is looking much rosier than on February 1st. March through May typically make up about 25% of the typical seasons snowfall, so the story isn’t over yet, but it’s not a horror novel anymore.
Big Hole Sub-basin Snowpack: 108% of normal (1981-2010 median)
Period of Record Monthly Climate Summary – Period of Record : 01/01/1923 to 06/09/2016
See details below from Western Regional Climate Center:
WISDOM, MONTANA (249067)
|Average Max. Temperature (F)||26.4||31.1||38.5||49.2||60.3||68.6||79.4||77.8||67.6||55.0||38.0||28.0||51.7|
|Average Min. Temperature (F)||1.2||3.3||10.8||21.2||28.7||36.1||38.2||34.7||27.8||21.3||12.3||3.6||19.9|
|Average Total Precipitation (in.)||0.70||0.52||0.74||0.95||1.64||1.96||1.09||1.03||0.99||0.83||0.76||0.77||11.97|
|Average Total SnowFall (in.)||11.8||8.3||8.6||4.5||2.5||0.5||0.0||0.0||0.5||1.9||7.8||10.8||57.0|
|Average Snow Depth (in.)||9||10||8||1||0||0||0||0||0||0||2||5||3|
Percent of possible observations for period of record.
Max. Temp.: 98.7% Min. Temp.: 98.6% Precipitation: 98.6% Snowfall: 76.4% Snow Depth: 50.3%
National Water Supply Reports
Nation-wide information for water supply and climate prediction & forecasts.
Montana Water Supply Reports & resources
Statewide information for water supply and drought conditions. Report breaks out conditions by major basins:
Water supply and drought condition information specific to the Upper Missouri Basin:
Water Monitoring Resources from the Montana Watershed Coordination Council
Past Streamflow & Snowpack Reports