An experiment in northern Alaska has been carried out to evaluate the accuracy of snow water equivalent (SWE) estimations in tundra snowpack. In northern basins, water constrained in the snowpack contributes significantly to both the seasonal and annual water balance. It is critical to realize and address the problems of measuring and processing observational snow data so that this data can be used properly to advance understanding of changes in hydrological systems. A combination of well-developed depth hoar at the base of tundra snowpack and extensive surficial organic soils in permafrost regions can significantly affect snow water equivalent and snow depth sampling accuracy. Experiment in Alaska's Arctic suggest that end-of winter SWE can be overestimated from 4 to 20% depending on the sampling techniques applied. This error results from the fact that the depth of tundra snowpack is often overestimated. As observers probe the snow depth, it is difficult to recognize the snow-ground interface, and organic material is often incorporated into the snowpack depth estimate. This causes the average snow depth to be overestimated by 11 to 31%.