Powder Forecast –Friday, January 31st, 2020
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)
Sat 2/1 =0”
Sun 2/2 =0”
Mon 2/3 = 1 – 3” (H20 = 0.20” – 0.30”)**4
Tue 2/4 = 0”
Wed 2/5 = 0”
Thu 2/6 = 0”
Fri 2/7 = 0”
Sat – Mon 2/8– 2/10 = 0 – 3”
January Snowfall = 13”
January Forecast = 13″
Detailed 4-day Snowfall Forecast:
Sat 2/1—No snowfall expected
Sun 2/2 — Dry and windy during the morning, then light snow during the afternoon and evening hours, tapering off overnight. Accumulations 1 – 3”, ~3” up top
Mon 2/3 and Tue 2/4—No snowfall expected both days
Short Term (Days 1 – 4):
Infrared satellite imagery (below) shows high pressure off the coast building into CA through tomorrow for continued fair and unseasonably warm weather. Temps Saturday could reach into the low to middle 40s up top, middle/upper 40s at McCoy and middle/upper 50s at Canyon for an early February thaw.
Models then move an upper-level trough through CA on Sunday and Mammoth early Monday (image below) for much colder weather, gusty winds, and some light snowfall Sunday afternoon and night.
The numerical guidance is only favoring light amounts of snowfall with both the GFS (image below) and ECM models showing under a quarter inch liquid. So it looks like only a couple inches of snowfall and it will be the dry/cold fluffy type. Likely not enough for powder conditions and a good set-up for dust on crust after the warmer weather.
The system will slowly move eastward through Tuesday for continued cold temperatures and gusty north/northeast winds. Temps should remain in the single digits and low teens Monday before warming up into the upper teens and 20s Tuesday.
Long Range (Days 5+):
The models (ECM below) then rebuild the ridge back into CA and Mammoth by the middle part of next week for a return of fair and warmer weather. Temperatures by Friday will warm to close to the current event for another brief thaw before colder weather develops over the following weekend.
The models are favoring another high latitude type upper-level trough to move southward into CA by around next Sunday (ECM image below). The GFS (two images below) is deeper than the latest ECM, but these types of systems usually lack a good moisture tap since they are coming from the North and neither model is showing large amounts.
The deeper GFS is showing an inch or two of snowfall more than the ECM model that is only showing a couple of inches of snowfall. The Canadian is also only showing light amounts and the ECM mean is very dry and not showing much at all. Forecast could change since it is 10 days out with the current thinking favoring only very light amounts and possibly dust on crust again.
The GFS (image below) does move another deeper trough southward into CA over the following week and this one does have a more over-water trajectory and a better chance for snowfall. However, the ensemble guidance favors a more inside slider trajectory and a drier outlook. Overall, the forecast for early February does look colder now, but not necessarily wetter and thus no clear signs of the next legit powder day. WG