12-hours ending at xxxx MST	Precipitation	Snowfall	Core	Snow Depth	Total SWE
Mon 3/17 0700	Trace	0.0	0.0	0.0	0.0
Mon 3/17 1800	0.39	0.0	0.0	0.0	0.0
Tues 3/18 0700	1.70	8.0	1.72	8	1.71
Tues 3/18 1900	1.60	10.0	1.63	17	2.94
Wed 3/19 0700	1.53	14.0	1.87	27	4.0
Weds 3/19 1900	.08	T	0.00	23	4.0
Thur 3/20 0700	0.00	0.00	0.00	21	3.9
Storm Total	5.30	32.0	--	--	--

 

Storm totals of water equivalent for comparison

8" standard rain gauge (the one we use as the "official") 5.30"

4" CoCo RaHS gauge 6.17" (it is normally slightly higher than the 8" gauge, since it is closer to the ground, experiences lower wind speeds, and does not absorb and evaporate as much as the dark metal SRG, but usually the difference is no more than a few hundredths. Most of this large discrepancy resulted from the fact that the small gauge totally cappedover Tuesday night, so the Wednes AM observation was very suspect. Were it not for that problem, it's total would have been 5.45" -- the type of difference we are accustomed to seeing between the 4" and 8" diameter gauges sitting side by side.

Sum of 12-hour core samples from snow board 5.22" This does not include the moisture that fell as rain on Monday. These reading compared very favorably with the Standard Rain Gauge measurements except for the 0700 observation WEds AM when the snow board was drifted over and appeared to have an unrealistically high core reading. The excess in the Weds AM core sample was likely very close to the amount of precipitation falling as rain prior to snow accumulation.

Core sample of total snow water equivalent on the ground -- reached a maximum of 4.00" both at 0700 and 1900 obs on Weds. This is lower than the others, and is expected to be lower, since it does not include the rain that fell and does not include any melt that is occurring from the bottom of the snowpack -- and it is melting slowly from below due to warm soils.

Total accumulation from the dual-traverse Universal weighing bucket precipitation gauge was exactly 6.00" Not sure why this is so much larger than the SRG. It usually compares very favorably with the manual Standard Rain Gauge a few feet away, but Scott found it completely crowned over with snow Weds AM at 0700. It is possible that the crowning, and the process by which it melted, retracted, and was loosened to fall into the bucket may have resulted in "over catch"

Fischer-Porter Recording gauge. This unattended gauge recorded a storm total of 5.2". The time distribution of snow water content matched the Standard gauge until the last 24 hours of the storm when snow was sticking to the top and sides of this tall gauge. It may have slightly poorer gauge catch efficiency due to it's height, but when it warmed up yesterday, and the snow from the top melted and fell in, it compared VERY favorably with the Standard Gauge.