Snowmelt season

Fine weather snowmelt conditions. Stage = 50cm, Tw = 8C.

From the hydrograph below we can see that fine weather snowmelt conditions begin over the last few days of March and into April, as indicated by the daily fluctuations or sine wave pattern. This is characteristic of streamflow hydrographs in snowmelt regions. As warm sunny days continue, the daily fluctuations rise higher and higher as groundwater levels rise. On top of this we have the influence of rainfall events, most notably on 30 March (18mm) and 7 April (36mm). However, these events do not reach the high stage of over 1m that was recorded on 14 February this year due to rain-on-snow.

Larch lysimeter site after snow has completely melted

Cedar lysimeter site after snow has completely melted

Time-lapse cameras showed that the snowpack had completely melted by 27 March at the larch site, while it remained four days longer until 31 March at the cedar site.