Powder Forecast – Tuesday, November 26th, 2024
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.
Sesame Snow Course
**Snowfall forecast confidence ranges from very low (1) to very high (5)
Wed 11/27 = 8 – 10” (H20 = 1.50” – 2.00”)**2
5-Day Storm Total at Main = 50”
Thu 11/28 = 0”
Fri 11/29 = 0”
Sat 11/30 = 0”
Sun 12/1 = 0”
Mon 12/2 = 0”
Tue 12/3 = 0”
Wed – Fri 12/4 – 12/6 = 0”
Detailed 4-day Snowfall Forecast:
Wed 11/27 through Sat 11/30 – No snowfall expected all days.
Forecast Summary:
Short Term (Days 1 – 4):
This afternoon, the current infrared satellite image (below) shows subtropical clouds and moisture still streaming into the Central and Southern Sierra, resulting in moderate to heavy snowfall in Mammoth today. Radar (two images below) just before noon today shows the last pulse of moisture moving onto the Central Coast and eventually Mammoth for more snowfall this afternoon before snowfall ends by this evening.
The latest guidance differs somewhat significantly in terms of how much more will fall today, with the ECM model (image below) drier at about 0.75” liquid versus the GFS (two images below) at around 1.25”.
Forecast leans towards the wetter GFS that verified better with the storm with over 3.5” liquid at Main since yesterday. Thus, another 8-10” of base-type snowfall should fall today on top of the 20”+ that already fell yesterday/last night at Main for a storm total since last Friday around 4 feet at Main with 5 plus feet up top. Let the good times roll.
The trough swings inland tomorrow (image below) and high pressure will build north and west of California through the end of the week (two images below) and into the weekend for a return of fair and dry weather. Temperatures will warm up a bit through Friday before cooling slightly over the weekend and remaining mostly seasonal.
Long Range (Days 5+):
The longer-range guidance favors dry weather continuing for the foreseeable future or longer. The best guess as to when there will be another powder day would be after mid-December and possibly not until Christmas week, as all the guidance is dry through December 10th.
Next week’s pattern (image below) will be characterized by a Rex block along the West Coast and a reasonably deep trough across the eastern United States. Temperatures should be primarily seasonable or slightly warmer than average under mostly sunny skies.
A full latitude blocking high pressure ridge is then forecast to set up along the West Coast in the 11-15 day pattern (image below) and continue a deep trough for the eastern U.S. That ridge would shunt any potential storm well north of California and continue to produce fair and dry weather for Mammoth. Temperatures will probably edge a bit warmer and into the slightly above-normal ranges.
The computer guidance for December has changed a bit from the last post. The ECM (image below) has been showing dry weather for the month, and now the Canadian model (two images below) also favors dry weather. Only the CFS is still showing mostly average precipitation (three images below), but has below normal for NorCal that makes it’s output suspicious.
The thinking about the return of snowfall has not changed much from the last posting. It probably won’t happen until the MJO gets into the eastern part of phase 6 or phase 7 after mid-month and if the signal remains active, as has been the case for the past two months.
In general, the MJO is more active and a contributing factor to the northern hemisphere teleconnection pattern during ENSO neutral years or when La Nina or El Nino is very weak, which is the case this year with a very weak La Nina or negative neutral ENSO likely this winter. WG
