Good radiational cooling led to a low of 29F this morning. Strangely, despite mostly sunny skies, temperatures have lagged behind modeled, perhaps due to the lack of wind and downsloping wind to help vertically mix the column and remove the shallow but very strong nocturnal temperature inversion, especially with the weaker sun angle of October. It will not cool down nearly as much tonight with a bit more wind and a lot more mostly mid-level cloudiness ahead of a cold front. The low will likely occur at the end of the period (Thursday 06z) after the cold front passes and with clear skies, though there may be a bit too much wind for ideal radiational cooling, similar to Sunday night. However, the wind at the end could be near the threshold for radiational cooling, and a few dips are possible; perhaps not a good time to stray from models too much. Temperatures will slowly rise tomorrow as cold advection behind the cold front and solar heating compete. Unlike today, the cold advection will lead to much more mixing of stronger winds aloft down to the surface, with winds also being closer to parallel to the valley oriented west-northwest to east-southeast. The cold daytime model bias will also likely re-appear, like previous days, with no trouble mixing. Note how the MOS, based on statistics, is much higher than the other models! Actually, I think the forecast from 3 days ago is a good analog to today's forecast.
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