Day 1 of Medford, OR (KMFR)

Partly to mostly cloudy skies early in the night, along with almost calm wind, will lead to some radiational cooling mitigated by the rather moist low-level air and some clouds, before it becomes completely cloudy later in the night, which will likely stop the cool down or slow it down a lot. KMFR tends to cool down a lot with good radiational cooling, so I expect some quick little dips possibly slightly below model guidance before becoming truly overcast after 06z, with the low possibly near the start (Tuesday 06z). Interestingly though, some models show it continuing to cool down after 06z tonight even with the clouds – perhaps the clouds are not particularly thick or break up at times?

 

The increasing clouds are associated with a storm approaching the Pacific Northwest that will move over the region tomorrow, but it is not particularly strong, and with the rain shadow effect from the Cascades to the west, only light rainfall amounts, if any, are expected in Medford. The cloudy sky will lead to only a slow warmup tomorrow at least through early afternoon, though a few breaks in the clouds later in the day could cause more of a warmup then. Even with the storm approaching, it is weakening and staying mainly to the northwest, with only weak pressure gradients in the area, leading to very little wind. Perhaps there could be a bit of westerly wind in the late afternoon with the sea breeze effect if there is enough sunshine and daytime heating.

 

Source: PivotalWeather