Powder Forecast — Tuesday April 18th, 2017
Ted Schlaepfer CCM —- Mammoth Mountain WeatherGuy
Dry weather returns Wednesday and continues rest of the week with warmer temps by Friday and spring conditions everywhere on the mountain this weekend. Colder and windy weather with a chance for light snow is then expected by Tuesday next week with a slight chance for light snow at times end of next week and again beginning of May. Generally seasonable weather with just a slight chance for an infrequent spring storm is then expected through mid-May or longer with spring conditions on the mountain.
Next update Saturday 4/22
Snowfall forecast are for the Sesame snow course (Main Lodge)
**Snowfall forecast confidence ranges from very low (1) to very high (5)
Actual Monday/Tuesday = 10.5” (H20 = 2.00”)
Wed 4/19 = ~8” (H20 = ~1.20”) **5
Thu 4/20 = 0”
Fri 4/21 = 0”
Sat 4/22 = 0”
Sun 4/23 = 0”
Mon 4/24 = 0”
Tue 4/25 = 0 – 3”
Wed – Fri 4/26 – 28 = 0 – 3”
April Snowfall = 61”
April Forecast = 70 – 75”
Seasonal Snowfall = 612”
Seasonal Forecast = 625 – 640”
Detailed 5-day Snowfall Forecast:
Wed 4/19 through Sat 4/22 — No snowfall expected all days.
Satellite imagery (below) shows the back end of a moist cold front now moving through the Mammoth area and snowfall will taper off this evening. The front ended up being a lot more productive on the precipitation side, but unfortunately, snow levels stayed higher than forecast and did not come down as fast as expected.
Nonetheless, Main lodge picked up close to 20” with Canyon lodge receiving a lot less and mostly rain for the bulk of the event. I measured a solid 2 feet at the top of Blue Ox run early this afternoon so there is probably two and a half feet or more up top. The snow is very heavy thick Sierra cement and the wind increased this afternoon so the snow up top may be wind affected along with the colder temps behind the front.
It will be bluebird morning Wednesday for the powder up top with spring conditions likely returning for the lower part of the mountain by the afternoon with winter up top. The next front and upper level low pressure system pictured in the satellite image above will move to the north of Mammoth early Thursday resulting in just an increase in NW winds. Temps will warm up by the afternoon with spring everywhere but the top where there could be some wind buff.
High pressure will continue to build over CA Friday and Saturday for fair and warmer weather. Spring conditions are expected everywhere on the mountain by Friday afternoon. The latest ECM model (image below) now moves a trough north of Mammoth on Sunday and Canyon closing day which would mean just slightly cooler temps and breezy conditions for the pond skim.
The longer range ECM model (image below) is bringing a stronger upper level low to the coast around next Tuesday with a fairly strong front moving through NorCal. It clips Mammoth with moderate snowfall early Tuesday adding up to almost half an inch liquid or a solid 3” snow. The GFS and Canadian models are not as strong and a bit farther east with the low pressure system. Right now it doesn’t look like enough for powder conditions, but there is a chance if it digs farther southward before it moves east.
The ECM develops a deep upper level trough across the intermountain West late next week with short waves moving through Mammoth as slider type storms middle and late next week for periods of light snowfall. The GFS is farther east with the trough and has the ridge off the coast nudged closer to CA for fair and typical spring weather.
The current forecast for next week is a blend of the models which is similar to the ECM ensemble mean. It has small amounts next week starting Tuesday and not enough each day for powder conditions, but dust on crust. These nuisance lows are typical during spring when everyone wants spring turns but these lows produce firm snow and windy conditions.
The GFS ensemble mean has a weak trough along the coast to start May (image below) which would represent another chance for light snowfall, but it is really too far out to know for sure how it will play out. The climate models are generally favoring normal to slightly below normal precipitation through mid-May under a progressive pattern of lows moving into the PacNW.
Overall, I am not expecting any big storms moving forward with just a chance for occasional weak storm and windy conditions, starting Tuesday next week. The snowpack has now reached an apex and now spring has arrived. WG