Meteorology Monday - 01/16/2023

Today we will deal with the different types of fog.

Advection fog forms when warm moist air overrides a cool surface. This happens in the Midwest when there is snow on the ground and warm moist tropical air moves up from the south in the spring.

advection fog IL.jpg

It also happens along the coast of California, Oregon, and Washington when warm moist air from the Pacific Ocean overrides the cool coastal California current.

advection fog Hecita Lighthouse.jpg

Evaporation Fog forms when colder air overlies a warmer body of water. This is especially common during early fall when bodies of water still retain some of their summer heat and nighttime temperatures are much colder.

evaporation fog.jpg

Radiation fog forms when the temperature of the air drops below the dew point. Colder air sinks into low places because of its higher density and thus this fog tends to be prominent in low lying places.

radiation fog IL.jpg

Upslope fog forms when warm moist air rises up the side of a mountain. It cools as it rises and eventually reaches the dew point and forms fog.

upslope fog.jpg

Finally, there are fog bows which are the equivalent of rainbows, but because the droplets are so small, they don't show the colors of a true rainbow. This fog bow occurred on the slope of Haleakala on the island of Maui.

fog bow.jpg

You don't have to pile on with fog images. Please pile on with any cloud images you choose.
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Staff member
Doug, those are awesome! What a great topic for this week. Though I have very little fog images, so I have to really think when or where I had captured some fog.
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