Summary. October 21, 2018
Light snow is going to return to the San Juan mountains of Colorado above 9500 feet this week (Tuesday) that spreads some moisture north later in the period. The East is going to see a good shot of of high elevation snow in the midweek timeframe. The Pacific Northwest gets “Wet” late this week with warm temperatures. The good news Is that the PNW seems to stay active with some cold air possible pushing south at some point in early November. The Rockies could see snowfall in early November in our extended forecast.
Short Term Forecast
Moderate moisture will be falling over the 4 corners this week. Light snow will be falling above 9500 feet in the high mountains of Southern Colorado on Tuesday under SE flow. Winds are not optimal for any of the ski areas but it’s possible that Wolf Creek nab 3-6 inches by late Tuesday. Some snow is going to push as far north as Summit County along the Continental Divide late Tuesday/Wednesday. My confidence is low for anything more than a light tease at the highest elevations.
Below: Early Wednesday morning – light or moderate in the San Juan’s (Winds are not optimal for ski areas). Image- WX Bell
Moisture and some cooler air will be moving into New England this week. Any snow that falls will be late Tuesday to Thursday AM. The Euro model is bullish for moderate or heavy snow for the northern interior of Maine (Sugarloaf may score), while the GFS pushes moisture further west over northern New Hampshire and the green mountains of Vermont. Areas from the White Mountains of New Hampshire, northern Vermont and north central Maine will likely see some light snowfall through Thursday morning. Current amounts for many northern ski areas should stay in the 2-4 inch range at the summits with less at the bases. Higher amounts might be found closer to the Canadian border.
The mid week pattern will shift an increasing onshore flow of moisture aimed at the Pacific Northwest and Canada.
Below: Moisture increasing in the PNW midweek with some snow likely over New England (WX BELL)
Several rounds of moisture will be overspreading the PNW mid to late this week. Warm air and southerly flow will keep any snow to the highest Cascade Mountains of northern Washington or in British Columbia. Primarily rain will be falling at most ski resorts of Washington. Some high elevation snow is likely late this week over Whistler with slightly cooler temps and higher elevations. Cooler air is likely to infiltrate these regions by the end of October bringing snow levels lower. Occasional moisture is likely during these time periods. Decent amounts of snowfall are possible at the summit of Whistler.
The long term ensembles are in agreement of a return of colder temperatures for much of the west at some point around Halloween. Colder air will push into the Pacific Northwest, Rockies and even the Sierra during the first part of November. Ensembles show hints of moisture bringing snowfall to much of the the West during the early November period. I am most bullish for the the Pacific Northwest and Rockies with some optimism for the Sierra by November 3rd. We will narrow in the models as we get closer (Low to moderate confidence on who gets the most snow. High confidence in some pattern changes but details remain unclear over 7 days out.
Below: Cooling for much of the west beginning October 31st. (WX Bell)
Below: Moisture is possible over much of the west in the early Nov. timeframe (WX Bell)