2014-09-17 FCST: AZ (Flooding)

[Warren Faidley]

Figured I'd start a thread concerning the potential of serious flooding here in Southern Arizona over the next 3-4 days. I've heard multiple chasers are heading this way to cover the event.

The GFS is still showing pockets of 3-5 inches of rain in the region. One of the biggest problems concerns rainfall in the mountains that can quickly flood low-lying areas with little or no warning. If you are chasing here, and don't have a lot of experience with desert flooding, it often develops like a dam burst and levels can rise at alarming rates. It's also quite easy to become trapped between two flooded roadways, so choose your routes carefully.

Another lessor concern is shear near the core, if it remains intact, we could see a brief spin-up in or to the east of the core. The core should show up on radar if it holds together.

It's a shame chasers and spotters cannot monitor emergency scanner frequencies anymore without advanced communication equipment. Scanners are life savers during floods, as I learned during the 1983 (massive) floods here in Arizona. Some websites offer scanner coverage for southeastern Arizona.

I'll be posting live updates on my Facebook page.

Stay safe!

Warren

 

[Warren Faidley]

Looks like this could be a major forecast bust for Tucson, which is a good thing. Trends in the IR, visible and water vapor satellite loops seem to suggest the serious impact from Odile may be lowering, or at least moving east of Tucson into the SE corner of the state and into SW New Mexico.

The most recent runs of the RAP and GFS support this, although a stay band or storm could still cause localized flooding.

I could be wrong of course so no one should let their guard down yet.

W.

Edit: The 18z NAM maintains the flood potential. We will see.

 

[Greg Campbell]

Given how the relatively narrow corridor of maximum precipitation has been wandering from model to model, run to run, I'm a little surprised that the local NWS office pushed the Panic Button as hard as they did. Of course the media has been doing what they do best, running scary stories and offering advice on where to buy sandbags and other end-of-the-world supplies.

Reporting 0.1" in eastern Tucson as of 6pm

Areas to the SE of town have received 2+ inches, with more on the way.

 

[Warren Faidley]

Yea, there was a lot riding on the system holding west on the left side of the ridge - and I also had a problem with the narrow precipitation forecast. It was hard call regardless and it could have been a total disaster. These tropical systems are always very difficult to forecast. Glad it worked out for Tucson, but I'm not sure about regions to the SE like Bisbee. They are surrounded by mountain streams and the town is a disaster waiting to happen when it floods.

Now we have Hurricane Polo, and it might take a more western route before turning east.

W.