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Weather Software => GRLevel X Software => Topic started by: WeatherBeacon on May 26, 2008, 08:29:07 PM

Title: GRL3 Radar of Latest Tornadoes?
Post by: WeatherBeacon on May 26, 2008, 08:29:07 PM

Does anyone have any GRL images of the latest tornadoes to post? I'm still hoping to purchase GRL3, but for now I'd sure be interested in seeing your GRL3 images of the latest tornadoes! If you post any, please indicate which radar type you used.

Thanks!

Kevin...
Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: WeatherHost on May 27, 2008, 06:55:23 AM
What are you looking for specifically?  Any certain storm?  Are you looking to see the hooks?  Or the reflectivity couplets?

GR has a variety of products that display different images.  One of us should be able to pull down the archived L3 data and grab a screenshot or 10 if you want to see a specific storm.

Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: WeatherBeacon on May 27, 2008, 09:16:46 AM

What are you looking for specifically?  Any certain storm?

No particular storm, but I'm surprised that someone hasn't posted GRL images of the monster Colorado tornado. I would think that one would have a very distinctive signature.

Are you looking to see the hooks?  Or the reflectivity couplets?

Yes to both. I've used the 3 week trial offer of GRL3 twice--once last year and again last month. In April (into May) I used it to watch tornadic storms all around the country, trying to learn how to use and understand how to read the GRL3 images. I'd see images with the little TVS triangle and all, but I wanted to understand how to read the images myself. For example, where's the hook echo? I'd also see reds and greens side by side with a tornado icon near it, but I'd also see reds beside greens elsewhere with no tornado icon, which left me wondering, "What's the difference?" So I'm always left wondering, "How do you read these images? What are the meteorologists looking for?"

I figured many GRL3 users would have images of the latest tornadoes and might post some that show what one would look for in a radar to identify a tornado (other than the triangle icon).

Thanks!

Kevin...
Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: Mark / Ohio on May 27, 2008, 08:25:49 PM
Kevin,
I'm still working on figuring that one out myself.  When I get the chance I fire up my laptop and look at those big storms while watching the weather channel.  Then I compare what they are pointing at compared to what I see.  Also sometimes I think the warning circles tend not to fall exactly where the tornado is at since it can be moving very quickly.  When that happens the hook may be a number of miles N.E. of the rotation indicator.  Also I've been looking at "Echo Tops" and "Vertically Integrated Liquid" displays.  Sometimes those displays get pretty colorful out West compared to the lower level stuff we more commonly have here until the summer heat and humidity kicks in around July.

Edit added:  Reason I use my laptop is this old desktop that runs my weather data does not have a good enough video card to allow the smoothing feature to work on it.
Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: WeatherBeacon on May 27, 2008, 08:32:27 PM

Hi, Mark.

Kevin,
I'm still working on figuring that one out myself.

Okay. Glad I'm not alone. I'd like to learn how to read them.

When I get the chance I fire up my laptop and look at those big storms while watching the weather channel.  Then I compare what they are pointing at compared to what I see.

Right. I was watching some storms in our area that the local TV meteorologist said was showing rotation, and I couldn't see anything suspicious in GRL3.

Also sometimes I think the warning circles tend not to fall exactly where the tornado is at since it can be moving very quickly.  When that happens the hook may be a number of miles N.E. of the rotation indicator.

Yep. I wondered that, too.

Also I've been looking at "Echo Tops" and "Vertically Integrated Liquid" displays.  Sometimes those displays get pretty colorful out West compared to the lower level stuff we more commonly have here until the summer heat and humidity kicks in around July.

Okay. Thanks for the feedback, Mark!

Regards,

Kevin...
Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: Mark / Ohio on May 27, 2008, 09:02:44 PM
...

When I get the chance I fire up my laptop and look at those big storms while watching the weather channel.  Then I compare what they are pointing at compared to what I see.

Right. I was watching some storms in our area that the local TV meteorologist said was showing rotation, and I couldn't see anything suspicious in GRL3....

I've done that too.  Makes me wonder sometimes if the time lag to what they are showing is greater or less then what we see with GRL3. 

Another thing I started doing this year was listening to the ham operators reporting what they see on site compared to what I see on the radar.  They use 146.76 Mhz here for severe weather spotter reports.  There again there can be up to a 10 minute lag in the radar data sweep.  I think that is the minimum time it takes for Doppler to make a full data sweep.
Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: WeatherBeacon on May 27, 2008, 09:19:30 PM

....
There again there can be up to a 10 minute lag in the radar data sweep.  I think that is the minimum time it takes for Doppler to make a full data sweep.

I recall reading about that somewhere.

I really like GRL3 and have read great things about it on the forum. I hope to make that my next weather related purchase, and I would be very interested in learning how to read the various images.

Anyone else? Images of the recent storms?

Thanks.

Kevin...
Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: WeatherHost on May 28, 2008, 04:26:00 AM
A good clear hook echo or reflectivity couplet will jump right off the screen at you.  They are very easy to pick out.  The problem is, that not all of them are that clear, they can be buried in other data.  Also, the formulas used to identify mesocyclones and TVS indications are complex and can pick up false data.  The scans are completed in about 6 minutes (the time needed for the radome to complete a full scan of all tilts), then the data is processed and distributed, although I have seen some shorter intervals for some reason.

(http://www.grlevelx.com/owners/download/file.php?id=225&t=1)

(http://www.grlevelx.com/owners/download/file.php?id=217&t=1)

(http://www.grlevelx.com/owners/download/file.php?id=215&t=1)

(http://www.grlevelx.com/owners/download/file.php?id=213&t=1)

(http://www.grlevelx.com/owners/download/file.php?id=212&t=1)

(http://www.grlevelx.com/owners/download/file.php?id=222&t=1)

(http://www.grlevelx.com/owners/download/file.php?id=191&t=1)

These are all from recent storms.  They're all from GR2, but you'll see basically the same thing in GR3.  GR3 is more user friendly for general users, GR2 is more geared for advanced users.



---

Announcement that the Parkersburg, Iowa storm has been rated EF5:

http://www.crh.noaa.gov/crnews/display_story.php?wfo=dmx&storyid=14909&source=0

Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: anchorageweather on May 28, 2008, 08:59:08 PM
Yikes, what a monster!
Title: Re: GRL3 Radar of Latest Tornadoes?
Post by: WeatherBeacon on May 28, 2008, 11:13:06 PM

Yeah, those are some very telling images! Thanks.

Any others out there?

Kevin...