Powder Forecast –Tuesday April 27th, 2021
Ted Schlaepfer CCM —- Mammoth Mountain WeatherGuy
Snowfall forecasts are valid at the Sesame snow course (Main Lodge) for the prior 24 hours as reported in the 6-7 AM morning snow report.
**Snowfall forecast confidence ranges from very low (1) to very high (5)
Wed 4/28 = 0 – 1”
Thu 4/29 = 0”
Fri 4/30 = 0”
Sat 5/1 = 0”
Sun 5/2 = 0”
Mon 5/3 = 0”
Tue 5/4 = 0”
Wed – Fri 5/5 – 5/7 = 0”
April Snowfall = 5.5”
April Forecast = 5 – 6”
Detailed 4-day Snowfall Forecast:
Wed 4/28 through Sat 5/1 – No snowfall expected all days
Short Term (Days 1 – 4):
The visible satellite image (below) this afternoon shows clear skies over the valley and clouds over the Sierra where showers are developing this afternoon, including Mammoth. The snow showers will end this evening and only a trace and no more than an inch of accumulation is expected.
High pressure will then build into the region tomorrow and peak on Friday (image below) resulting in fair and warmer weather. Spring conditions are expected across the entire mountain by Thursday with temps rising into the low 40s up top and upper 50s at Main. Continued fair and slightly cooler weather is forecast for Saturday, but still likely spring conditions.
Long Range (Days 5+):
The longer-range guidance is generally showing a typical spring pattern with no clear signs of any powder days.
A weather system will move east of the Sierra as a slider type storm on Sunday (image below) and into Monday resulting in slightly cooler weather and probably an increase in winds. Spring conditions will likely continue for most of the mountain except for possibly the top that might firm up a bit.
Weak high pressure will build in its wake into the middle part of next week (image below) before another weather system approaches California toward the end of next week.
The ECM has it farther south (image below) while the GFS ensemble mean (two images below) places it farther northward. Either way, neither solution would result in snowfall in Mammoth and likely just cooler temperatures and increased winds.
The fantasy range period has a long-wave trough across the Interior West and a blocking high pressure ridge off the West Coast (image below). That pattern would result in a passing inside slider type weather system every few days and a chance for only light snow showers.
Overall, the ensembles are not favoring any powder days in the foreseeable future with the GFS ensemble mean showing less than a quarter inch of liquid (image below) for the 15-day period.
Unless there is a storm on the horizon, I will only be doing my Powder Outlooks weekly now on Tuesdays until the end of the season. WG