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Question about Radar

With the standard NWS radars, 0.5, 1.5, 2.4, and 3.4* tilts, what is the standard height increase per mile for those?

Say I was 60 mi away from the radar at a 1.5* tilt, how high is radar looking?
 
The roughly-correct equation is

H = R(tan L) + (R*R)/17000

where
H = height above radar level in km
R = range from radar in km
L = Elevation angle

60 miles = 96.56 km so at 1.5 degrees the altitude is (96.56 * tan 1.5) + (96.56*96.56)/17000 = 3.08 km above radar level, or about 10,100 feet.

Hope that helps.
 
With the standard NWS radars, 0.5, 1.5, 2.4, and 3.4* tilts, what is the standard height increase per mile for those?

Just to point out, those tilts are the the tilts available on the NIDS feed. The NWS offices have many many more levels at their disposal, and Level II data provides many more, different levels... E.g. a quick look at my level II data shows 0.5, 0.8, 1.2, 1.7, 2.2, 3.0, 3.9, 5.1, 6.2, 7.8, 9.8, 12.3, 15.5, 19.3 degree tilts available (as viewed on "GRW88Level2" while the radar is operating in VCP12)... Of course this depends on the VCP that the radar is operating in.
 
You checked out GRWW88D level 3 Jeff? I see no reason to use any other radar service after using that. Live radar within several minutes, auto update, GIS support. yum!

Aaron
 
Here are the different tilt angles for the different VCP's, somebody correct me if this has change. I have notice small variations in terms of degrees in some of the tilt angles, that are listed in different literature.

I have notice when using Level 3 data, you will see a differece of 0.1 degree in the tilt angle, depending on source of your radar data, you are getting over the internet. Example of different tilt angles: 2.4 degrees for Weather Tap, 2.5 degrees for College of Du Page for base reflectivity, or storm relative velocity images.

Precipitation Mode Strategy:
Volume Coverage Pattern 11 (VCP 11) scans 14 elevation (tilt) angles in 5 minutes
Elevation (tilt) angles: 0.5, 1.45, 2.4, 3.35, 4.3, 5.25, 6.2, 7.5, 8.7, 10.0, 12.0, 14.0, 16.7, 19.5 degrees
Elevation (tilt) angles: 0.5, 1.50, 2.4, 3.40, 4.3, 5.30, 6.2, 7.5, 8.7, 10.0, 12.0, 14.0, 16.7, 19.5 degrees (from other sources)
Volume Coverage Pattern 12 (VCP 12) scans 14 elevation (tilt) angles in 4.1 minutes
Elevation (tilt) angles: 0.5, 0.8, 1.2, 1.7, 2.2, 3.0, 3.9, 5.1, 6.2, 7.8, 9.8, 12.3, 15.5, 19.3
Elevation (tilt) angles: 0.5, 0.9. 1.3, 1.8, 2.4. 3.2, oops lost my notes on the rest of the elevations, lol

Volume Coverage Pattern 21 (VCP 21) scans 9 elevation (tilt) angles in 6 minutes
Elevation (tilt) angles: 0.5, 1.45, 2.4, 3.35, 4.3, 6.0, 9.9, 14.6, 19.5 degrees
Elevation (tilt) angles: 0.5. 1.40, 2.4, 3.40, 4.3, 6.0, 9.9, 14.6, 19.5 degrees (from other sources)
Elevation (tilt) angles: 0.5, 1.50, 2.4, 3.50, 4.4, 6.0, 9.9, 14.6, 19.5 degrees (from other sources)

Clear Air Mode Strategy:
Volume Coverage Pattern 31 (VCP 31) scans 5 elevation (tilt) angles in 10 minutes
Elevation (tilt) angles: 0.5, 1.50, 2.5, 3.50, 4.5 degrees
Elevation (tilt) angles: 0.5, 1.45, 2.4, 3.35, 4.3 degrees (from other sources)

Volume Coverage Pattern 32 (VCP 32) scans 5 elevation (tilt) angles in 10 minutes
Elevation (tilt) angles: 0.50, 1.50, 2.50, 3.50, 4.50 degrees
Elevation (tilt) angles: 0.50, 1.45, 2.40, 3.35, 4.30 degrees (from other sources)

Mike
 
Paul Sirvatka and the College of DuPage have a great little tutorial on doppler radar and applications:
http://weather.cod.edu/sirvatka/es115/unit.../radarnotes.pdf

At the bottom of the page, there is a figure showing the elevation of a radar beam given an initial angle and distance from the radar.

Hope that helps. Remember to keep in mind any elevation difference between the radar location and the point at which you want to look.
 
Thanks, Aaron. That website seems to be just a users' forum to the radar itself, but I can probably find out from it how to access the actual radar.
 
You checked out GRWW88D level 3 Jeff? I see no reason to use any other radar service after using that. Live radar within several minutes, auto update, GIS support. yum!

Aaron

:shock: No, I hadn't seen the Level III program before now. I've used the LII program for the past couple of months ... But this LIII program -- WOW! Who needs Storm Lab, Weathertap, etc etc etc?! This program does it all, pretty much... All 4 NIDS tilts -- on bref, radial, SRM, VIL, echo tops, storm attributes table, county warnings, etc etc etc... and it's free!
 
level 2 linux apps

I was looking at this page https://www.radarservices.org/technical.php#NEXRAD regarding level2 data and it looks interesting.

I may go through with a plan of setting up my linux webserver to gather nexrad2 data and then deliver the images as gifs, jpegs or png os webpages.

I am new to meteorology and storm chasing but I have a lot of experience with linux/unix webservers and other internet technologies.


Is anyone on this list experienced in setting up weather tools on linux machines? Any advice on apps that I should set up? Is it worthwhile to set up your own tools vs collecting data from other websites, weather.cod.edu for example. Could this help me overcome some of the problems I now experience, such as forecast skewT images failing to render correctly on many browsers?

It would be silly to reinvent the wheel but if I could set up my webserver so that it gathered data specific to a site that I was chasing that day it could certainly make my WiFI stops a little more efficient. As of now a WiFI stop involves logging in to the service(sometimes a lengthy process), hitting the spc site for Mesoscale discussions and warnings, Checking radar data, checking stormtrack target area forum. Usually WiFI is pretty fast once I get logged on but I always feel like I would stay and gather more data if I had the time but time is usually in short supply.
Also it seems that once the tornado warning goes up it is usually 15 minutes behind real life. So if you are not in the target area already you had better be awful close. So it would be nice to have data good enough to predict the warning BEFORE they do.

The dream would be to have my webserver do some virtual chasing in my target area and call me on my cell phone when it detects a hook echo a tornado vortex signature or any other interesting data. Sort of a "virtual nowcaster" . I can hear the automated voice now, "this is your computer calling, " Just kidding... I think. A web page or some collection of data on the target above and beyond what I gather now might be nice.

It might also help me set up case studies so I can study a stored collection of the days events and try and figure out why things played out the way they did. Just seeing what is out there. What sort of Linux based weather apps do other storm chasers have set up?

Thanks,

Tom
 
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