Here comes our first round of Winter

TUCSON – While Winter is officially three weeks away, Mother Nature is sending a Winter-like blast of rain, snow and cold air to southern Arizona. 

A cold front will sweep through the State late tonight and into Friday morning bringing plenty of changes. Valley rain and mountain snow begins around 1 am and should finish up by midday Friday. 

Rainfall amounts will be light – generally around 0.25″ or less in most spots while above 7000′ the precipitation will be in the form of snow. 

While October was a wet month for Tucson, no rain has been picked up during the month of November. 

Much cooler air will filter in for Friday and the weekend with highs only in the upper 50s to lower 60s. Rain is in the forecast for Sunday as well. 

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A What Kind of Cloud?

A big shout out to Amie Montes who captured an interesting cloud photo taken today near Willcox.

Here is the photo, and at first glance it certainly looks like it could be a funnel cloud.

Beaver Tail Cloud

What do you see?

Okay here’s the scoop. Without seeing video we don’t know if the cloud is rotating.

Looking back at our Doppler radar from earlier today, there was no indication of rotation in any of our afternoon storms.

So the question is, what kind of cloud is this? The answer: a Beaver Tail Cloud.

Beaver Tail Clouds form in the boundaries between a thunderstorm’s updraft and downdraft.

In the storms downdraft, the heavier rain-cooled air descends and spreads out laterally.

At the same time, warm, moist air is being lifted.

As this warmer air becomes saturated it undergoes condensation and becomes visible in the shape of the ‘Beaver Tail’.

According to the American Meteorological Society, ‘the Beaver Tail shows that a supercell thunderstorm is getting its act together’

The Beaver Tail Cloud can become a much larger Shelf Cloud if there is enough low-level moisture.