Tag Archives: open cells

Open cells off the Washington coast

Excellent case of open cells of the Washington coast seen with WorldView, Turning to cumulonimbus onshore. April 1st 2015. It was the loudest thunder I ever heard in Seattle.

The image below shows a zoomed in portion, this time using the 3-6-7 MODIS channel blend (0.4,1.6,2.1 micron). Look carefully at the centers of the open cells. Quite a few have little patches of what I take to be evaporating precipitation/cloud. They actually show up slightly blue in the 3-6-7 blend.

WA_coast_open_cells_April1_2015_inset_367

Cold air outbreak over the North Atlantic (animation)

Here, we can see a cold air outbreak in this GOES-13 animation, using visible (day) and near-IR (night). This particular event shows offshore flow emerging from the NE US and Eastern Canada on the 6th March. The cold air floods over almost the entire North Atlantic region, eventually passing over the Azores (ARM ENA site, 39N, 28W) on the 8th March. The cold air outbreak is mared by open cellular convection in the low clouds. During the time that the cold air outbreak is over the Azores, the concentration of cloud condensation nuclei drops to lower than 50 /cm3, after the precipitation associated with the low clouds removes particles by coalescence scavenging. The event can also be seen on NASA Worldview.