Monthly Archives: January 2018

Storm approaches: more snow or more rain?

Forecast for winter storm approaching California coast and heading to the Sierra. Click for full size.

A weather system is approaching the California Coast and the National Weather Service forecast isn’t sure how intense the snow will be around the Tahoe area.

The storm could be more intense to the south and pack less cold air resulting in less snow or rain rather than snow. Initial snow levels are expected to start at 8000 feet in the mountains and then drop to around Lake level. None of the forecasts call for snow in the Reno area.

Rain in the mountains pushed up Truckee River flows through Reno. Click for full size.

 

 

The storm last week pushed river flows up to around 900 cubic-feet-per-second in Reno on Saturday and pushed Tahoe’s water surface elevation up about 1.3 inches.†

 

 

† Truckee River flows peaked today at 900 CFS at Pyramid Lake due to the distance of more than 40 river miles the water must travel. We still have a long way to go to recover from the dismal dry December 2017 to “make up” for the deficit in long-term average river flows over the drought years from 2000 to 2016.

Truckee River flows at Pyramid Lake.

Dry winter forecast appears more likely

December 2017 offered little rain or snow for the Lake Tahoe and Sierra.  The high pressure which has dominated the eastern Pacific Ocean has recently weakened allowing some small storms in. Today, January 5, light rain is falling in Reno but overall precipitation is likely to be light through Saturday; temperatures should remain well above normal for this time of year. A slightly stronger storm is on tap for Monday through Tuesday.

Jan-Feb-Mar 2018 precipitation forecast

However, the National Weather Service Climate Center projects that January-February-March 2018 will more likely see dry conditions because models show a higher probability of conditions that steer storms away from coastal California and the Sierra. Predictions are worse for elsewhere in the southwest with very dry conditions expected to continue.

Just last January 5, the Truckee Meadows saw flood conditions throughout the valley as well as in the Sierra Nevada and California. Major rain and snow events sent people scrambling for sandbags after a long, persistent dry period lasting 5 years, but extending back 16 years with only 2 wet winters since 2000 in 2005 and 2011. Sadly, it doesn’t look as if 2018 is off to a very good start on the water front. The health of the river needs high flows to improve conditions, regenerate the riparian, riverside forest, and provide enough water to support trout and other fish adapted to a cold water environment like the Truckee River.

I took these photographs almost a year apart that show the Truckee River where Hunter Creek comes in from the south at Mayberry Park and Bridge. Quite a change in conditions!

Flood conditions at Mayberry Bridge January 4, 2017.

Truckee River at Mayberry Bridge January 2, 2018.

Peter Gleick, founder of the Pacific Institute, was quoted in a recent Reno-Gazette Journal article warning us that our water outlook throughout the west is becoming more precarious due to unaddressed climate change. “While it’s too early to know for sure if this will be a drought year, we had better start acting as though drought was going to be a normal, not abnormal, part of western water’s future.” (emphasis added) The article went on to say that even last year with an over 200% normal snowpack, the low elevation snowpack – below 8,000 feet in elevation – was as much as 40% below the average. “That is exactly what we expect from climate change,” Gleick is quoted as saying. “The snowlike will move up because it is warmer.”

Present conditions: Check out the NRCS’s snow water equivalent map as of January 4, 2018. No, it is not good (unless you live in Montana or Wyoming).

Snowtel sites percent of normal snow water equivalent