Stealth Drought Hits Sierra Nevada in 2020
Dry Spell Yet Ahead
But Previous Wet Years Have Allayed Concerns.
I just heard from my son that Bridger Bowl near Bozeman, Montana had 6 ft of snow since FEB 1 and 220 inches for the season.But here in SoCal we have had only trace amounts of rain in 2020 and Mammoth Mountain is high and dry for many weeks.But we have had two good wet years out of five so the recent dry spell has not raised concerns yet.
Here is a quick review of period history in 2020:
Rainfall amounts in Los Angeles were 6.28 in. through January thanks to a wet December but still 0.44 in below normal. 2017-2018 was second driest on record with only 3 in at LAX. Wet winters in 2018-2019 and and 2016-17 built up snowpack an field reservoirs.
Mammoth Mountain Season total is 138 in. and 168 in. at Summit mostly in Nov. and Dec 2019. Last season had a slow start but 207 inches in Feb 2018 for a 2018 total of 492 inches. Recent years of low snowfall were 262 inches in 2017-18 and 176 inches in 2014-2015. So we have time to exceed the recent seasonal lows with a wet March.
As expected northern resorts have had good ppt in 2020. Big Sky Resort in MT received 80 inches of snow in February and has a 102 in. base on the upper mountain.
And plenty of powder with no crowds at Snow Basin in Utah.
The Climate Outlook for the next 14 days remains cold and dry in the West and warm and wetter in the North and East. Neutral conditions are in effect i.e no El NIno nor La Nina. Techies might look at other conditions affecting weather such as the AO and MoJo which have a greater effect under ENSO neutral conditions. Seasonal drought is developing in NorCal and SouthWest.
Here are short term maps and outlook. from NOAA and NWS.
This LATimes article says there are long term drought concerns,