Extremely Cold Nights Ahead

Home / Cold / Extremely Cold Nights Ahead

After a cold, snowy passed couple of days for a lot of locations, temperatures have not yet bottomed out yet, even after a good dumping of snow in the foothills, mountains, and locally in the valley.

Behind the storm system that dumped the low snow and lower elevation rain, even colder air lies behind it in the developing northerly flow.

4km NAM's forecast 850mb temperatures and 500mb heights, which give you a good idea of the northerly flow developing.

4km NAM’s forecast 850mb temperatures and 500mb heights, which give you a good idea of the northerly flow developing.

In most locations, winds will be quite weak, allowing strong radiational cooling to occur through the night and into the early morning. Locally though, northerly winds in the central and western side of the valley could locally keep temperatures a few degrees warmer than wind-sheltered locations. In the foothills and mountains, models indicate temperatures dipping into the teens, with single digits and negatives in the mountains and sierra. Teens and 20s are expected for much of the valley, with 20s and 30s all the way to the coast.

Any water on the ground will freeze rapidly tonight just a few hours after sunset, thus pockets of black ice in the foothills and mountains appear likely.

Overnight low temperature forecast for tonight/Sunday morning.

Overnight low temperature forecast for tonight/Sunday morning.

Nearly the same conditions are expected Sunday night and Monday morning, however some valley locations could be even colder due winds downsloping in the western slope of the sierra, transporting colder surface temperatures into the east side of the valley.

Cold overnight lows will continue into at least the middle of next week as the airmass slowly moderates as a strong ridge builds in.

At the moment next week appears dry, contradictory to what models indicated a few days ago. There are some long range indications of perhaps something getting in here for the following week, but that’s way to far out to put anything on, and for all we know models could trend wetter again for later this week.

Next update will come whenever we have potential for some more active weather.

Leave a Reply

%d bloggers like this: