Southwest Storm Brewing

Deborah in Phoenix writes:

My weather 'widget' says low 80's all week but takes a huge plunge Sunday--what's up Saturday night??????

The Web Site I usually look at is off-line at the moment, but this Web Site shows the situation well enough - a massive trough that develops off the San Diego coast and sweeps inland over the Southwest.

The modeled images represent the upper atmosphere (at the 500 mb level) every 3 hours. By sweeping downward, you can get almost an animated quality from the images. The big trough appears near the bottom as a massive yellow, red, and purple monster sweeping into Arizona.

Unfortunately we won't get much from it here in Sacramento (and it's been dry here lately), but Phoenix will see rain (and colder temperatures) for sure.