AccuWeather.com

The WeatherMatrix Blog

3-D Radar, Wind Graphs from 80-MPH Phoenix Dust Storm

Jul 6, 2011; 2:31 PM ET

UPDATE 9 AM: The NWS report is now available. They pointed out that downsloping was a factor, and they got a look at the dust storm via images from their new dual-pol radar what?. In addition, one town got more rain in 9 minutes than 9 months with this system.

UPDATE 3 PM: The storms that were formed by this system turned into a rotating Mesoscale Convective Vortex (MCV) over southern California (see satellite photos below plus this one from AccuWeather.com). I'm not sure if the collision of the two outflow boundaries caused this, or just the strength of the first boundary and resulting storms. See high-res animation and still capture below. There is also another video of someone using a car-mounted camera to drive into the storm. The CIMSS blog has more information on the MCV and MODIS also captured this high-res image:

We have an excellent news story "Very Large and Historic Dust Storm' Sand Blasts Phoenix" detailing what happened last night in Arizona. This is the best video I've seen showing the approaching dust storm (or "haboob"):

The Phoenix Haboob of July 5th, 2011 from Mike Olbinski on Vimeo.

The dust was tossed into the atmosphere over 20,000 feet into the air, as shown by the 3-D radar I pulled from GRAnalyst - in fact this is a rare case where what you see on the radar (hi-res | static | cross-section) looks exactly like what you see in reality, because it is picking up the dust as it overtakes the city. The dust storm was caused by a thunderstorm "outflow boundary" (see more below).*

The two-panel radar loop below (hi-res) is zoomed out, showing default radar (reflectivity) on the left and wind speeds (velocity) on the right. You can see the outflow boundary early on, moving northwest, then meeting another weaker boundary, moving southeast, and finally overtaking Phoenix.

One amateur weather station measured an 81 mph gust... which, although the sustained winds were low, I think is plausible...

Especially considering an official station (Davis-Monthan Air Force Base) topped out at 77:

The following photos are from AccuWeather.com Facebook fans.

The storm left a trail of wind damage and power outages as it moved from southeast to northwest:

*The way outflow boundaries are caused is illustrated thusly: Basically, cold air crashes down out of dying thunderstorms, hits the ground, spreads out, picking up dust on its periphery. As you probably noticed above, two outflow boundaries came together near Phoenix, but I'll await the NWS's report as to whether or not the two intercepting had something to do with the extreme winds. Sometimes when outflow boundaries interact, nothing happens; sometimes storms are formed (as shown SW of Phoenix in the radar loop), and sometimes they dissipate each other.

Jesse Ferrell

The views expressed are those of the author and not necessarily those of AccuWeather, Inc. or AccuWeather.com

blogs Home >

Comments

Comments left here should adhere to the AccuWeather.com Community Guidelines. Profanity, personal attacks, and spam will not be tolerated.

J's Breaking Weather News

WeatherMatrix on Facebook

The J-Cams in HD

About The J-Cams

More Jesse Ferrell

A Record Early Hurricane Season?

May 23, 2012; 10:39 AM ET

Both the Atlantic and East Pacific tropical seasons got an early start; could Tropical Storm Bud become the earliest East Pacific major hurricane on record?

Eight Days and Weak: Blogitis, Silent Sirens, Other News

May 18, 2012; 12:50 PM ET

So I haven't blogged in over a week -- at least I had my nose in a book. Plus: What you missed it you're not following me on social media!

Strange Vertical Sunset Clouds in Pittsburgh

May 10, 2012; 12:37 PM ET

There were strange clouds sighted last night at sunset in Pittsburgh. The clouds looked like tornadoes, but I've had experience with these.

LRR and Tornado Eye: Interesting Weather Radar Images

May 8, 2012; 2:41 PM ET

I've got a story about a newly-discovered supercell thunderstorm component, and a radar image that may show the eye of a tornado.

500,000 Lightning Strikes Provide Awesome Photos

May 3, 2012; 12:59 PM ET

Already this week, over half a million lightning strikes have hit the Earth over the U.S., making for incredible lightning photographs across the nation.

Incredible Photos, Videos of a Tornado in France

Apr 30, 2012; 10:00 AM ET

Beautiful pictures of a tornado were captured in Southwest France Sunday. I show the photos and videos, as well as a radar image.

Maps: Tennessee MCS Shoves on through

Apr 26, 2012; 11:55 AM ET

A terrifying-looking Mesoscale Convective System moved through Kentucky and Tennessee and into North Carolina this morning, and I've captured its lifecycle on maps.

Which Storm Took Down Myer-Womble Observatory?

Apr 25, 2012; 12:41 PM ET

High winds at 14,000 feet took out the U.S.'s highest observatory this winter, but when did it happen? I investigate observations from nearby stations.

April Appalachian Snow Photos and Timelapse

Apr 23, 2012; 1:18 PM ET

The April Appalachian snow event is underway, and I've got photos and two awesome timelapse videos.

Models on Possible Bookend Northeast Snowstorm

Apr 20, 2012; 9:28 AM ET

The models are starting to agree on a possible "bookend" snowstorm in the Northeast in a few days, but first, the front with a possible squall line.

Behind the Scenes: NWS Spring Media Workshop

Apr 19, 2012; 1:37 PM ET

It was a pleasure to attend the NWS "Spring 2012 Media Workshop" today. We discussed River Forecasting / Drought Status, Forecasting PA Thunderstorms and Social Media.

Harrisburg, Columbia Flood Comparison Photos

Apr 17, 2012; 11:02 AM ET

The trick with getting flood photos to look impressive is to compare them to the same place when it's dry. Last week I revisited the 2011 Pennsylvania Flood areas to compare.

Don't Have A Cow: Simpsons Springfield Weather

Apr 11, 2012; 12:36 PM ET

The Simpsons live in Springfield, but what state? It would seem that Matt Groening has now set the record straight, but whither the weather featured in the show?

Pennsylvania Spring 2011 vs. Spring 2012, in Photos

Apr 11, 2012; 12:13 PM ET

Every spring, people say that flowers & trees are coming out earlier than last year. This year, they really are and I set out to prove it, by comparing photos I took in 2011 to 2012.

Before and After Images from Arlington Tornado

Apr 7, 2012; 7:51 AM ET

Our aerial comparison of the Texas tornado damage was interesting to see, but I zoomed in and got a street level view too.