Fine weather snowmelt

Stage = 55cm, Ta = 11C

Fine weather snowmelt conditions have continued for the past two weeks. Precipitation of just 3mm on April 15 and 6.5mm on April 21 was barely enough to disturb the daily snowmelt pattern which dominates the hydrograph shown below. However, the fluctuations in stage due to snowmelt are less than 10cm and decreasing in magnitude which indicates that the snowmelt season will soon be finished for this basin.

Snowmelt season

First discharge measurement of the spring season, stage = 55cm, Ta = 7C

Snowmelt season is in full swing as you can see from the hydrograph above. First the hydrograph shows some small peaks in late January, followed by a period of steady flow recession during which time temperatures were mostly freezing.

Rain-on-snow and melt events start suddenly at the end of February, and you can see that during the second half of March the peaks are rising steadily as the basin becomes more and more saturated with snowmelt water, and groundwater levels rise. There is a moderate size rain-on-snow peak of almost 1.0m stage on 31 March (41mm of rain during 30-31 March). Recent cooler temperatures and the disappearing snow cover have led to river levels dropping. However, the daily snowmelt pattern is still clearly visible over the last three days of record.

Larch lysimeter site

Cedar lysimeter site

Young cedar lysimeter site with trace of snow remaining