They actually get more snow in March at these elevations, it doesn't melt until later in the spring... so while I agree a direct month comparison would be nice to see... this is still significant.

> The snow is melting so fast in the Sierra that, if it continues at its current rate, little would be left by early April. It’s unlikely to keep up this astounding pace, but there’s still high potential for the earliest melt-off on record in the state, according to Swain.

> “It feels like we skipped spring this year and dropped straight into a summer heatwave,” said Karla Nemeth, the DWR director, during Wednesday’s briefing. “What should be gradual snowmelt happened suddenly weeks ago.” This year’s was one of the quickest surveys they’d had, she added.

So the alarm here is the rate of melt, it should be sustained over a longer period. This is a problem because this is a natural "store" of water for downstream sources... if it's all released earlier it evaporates quicker and isn't replenished with more melt throughout the season.