Table of Contents for FAQs:

• Whats happened to the radar imagery in Version 2, NWS puts up a message saying "not available on this server"
• Is the Radar Imagery really Free?
• Other radar imagery is rectangular, yours is round, am I missing anything?
• Sometimes I see a message on the screen that says "no radar data available at this time" why ?
• What is the update frequency of the radar images?
• When does the Scan Zone Alert popup and warn me of a storm in my area ?
• How can I determine what color levels correspond to what storm intensities ?
• Why do I sometimes see what looks like a searchlight beam stuck on a radar image?
• Why do I sometimes see a solid circular pattern on the radar image?
• Why is there sometimes a lot of bright red and yellow radar echoes but no rain outside ?
• I notice the rotating beam on StormPredator is wider at the perimeter than at the center, does this have a purpose?
• Will SP run on....?
• Running SP on Macintosh
• I can't see the Exit button or SP fills the entire screen- do you have a solution?
• How do I put a custom basemap into StormPredator ?
• Storm Predator Website Help and Support

Click a topic above

What's happened to the radar imagery in Version 2, NWS puts up a message saying "not available on this server"

See the information on the NWS phasing old style radar imagery here

Is the Radar Imagery really Free?

Yes, absolutely. The NEXRAD radar network is owned by the Taxpayers of the USA, its data is public domain. There will never be a charge for accessing the radar images direct from the National Weather Service. The only exception may be that in the future, we may offer a subscription service for enhanced or custom radar imagery for a particular purpose, such as a custom private branded location. Or we may offer optional weather data, such as lightning strikes, where the data is gathered by a private company operating a nationwide network.

The basic NEXRAD radar imagery from the NWS will always be free, per the NWS policy. This is not to imply that the StormPredator program used to view them is free.

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Other radar imagery is rectangular, yours is round, am I missing anything?

No, even though it may "appear" that the round scan zone is "cutting off" the edges of a radar map...there is no radar imagery there at all, because the actual NEXRAD radar creates a round scan zone, not a rectangular one. For example, see the image below of Hurricane Isabel making landfall, which fills the entire circular scan zone of the Morehead City, NC NEXRAD image, but not the map corners.

Click to see the full size image and note that the cities of Danville and Georgetown have no precipitation showing, but you can be 100% certain that with a hurricane that close, they are getting heavy rain and wind, but the radar does not show it.

StormPredator makes use of this in its user interface to give you a radar display that truly representative of what is being seen by the radar. Square or rectangular radar images will have "dead zones" of background map at the corners with nothing plotted on them, which can give you a false sense of security for these areas by making you think there are no storms there, when in fact its simply not shown by the NEXRAD radar.

SP presents the traditional "radar scope" presentation that has been around since the inception of radar.

Version 3 supports a Square interface, use the hot key ALT-Q to toggle between square and round styles.

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Sometimes I see a message on the screen that says "no radar data available at this time" on a particular radar location, its been going on now for 24 hours or more, why can't you fix that?

That message screen comes from the National Weather Service, it’s the screen they put up when the radar is down for maintenance or there is some other problem that requires the radar image to be offline.  Like any system, they have scheduled maintenance and occasional failures. Since StormPredator obviously doesn't control the NWS radars around the USA, it's not something we can change.

What is the update frequency of the radar images ?

Image updates are based upon the operation mode of the radar at the time the image is generated. The WSR-88D NEXRAD Doppler radar is operated in one of two modes -- clear air mode or precipitation mode. Storm Predator checks for new images every minute, to ensure that your images are always updated. If it finds a new one, it automatically downloads it and displays it.

• In clear air mode, images are updated every 10 minutes.
• In precipitation mode, images are updated every five to six minutes.

When does the Scan Zone Alert popup and warn me of a storm in my area ?

This depends on several settings that you have to set correctly in the StormPredator Scan Zone. StormPredator Scan Zone settings are available by clicking the Scan Zone button in the left of the StormPredator main frame. To get an alert to popup and sound an alarm, four things have to be set and/or occur:

1. There must be an active Scan Zone defined on the map somewhere
2. You must have the Precipitation intensity slider set so that it will warn you for the type of storm you are concerned about
3. You must have the Sensitivity intensity slider set to a level that will trigger an alert.
4. There must be a sufficiently large and intense area of precipitation inside the Scan Zone that you defined on the map.

Generally, you can use the default StormPredator settings that are shipped with the program for the sliders and you'll get a popup alert on most types of storms. However, if you only want to trigger on very serious storms, or you want to detect when light precipitation enters your Storm Zone area, you may wish to changes the settings. If you are unsure, just set both sliders to the middle of their ranges.

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How can I determine what color levels correspond to what storm intensities ?

These colors correspond to storm intensity levels when the radar is operating in Precipitation Mode. Note that in StormPredator we image process the original NWS color levels as shown below to make the radar image easier to view and interpret. You can see the Color Key in StormPredator by pressing the ALT-K hotkey to display the current color scale and you can see where your Scan Zone Threshold settings are by press ALT-SPACE

The table below gives you an idea of what color processing we do in SP to make the image more viewable and what levels they correspond to.

NWS VIP COLORS	SP VIP COLORS		Precipitation Rate/type and Description
			75 DBZ Undetermined intense echoes or radar range folding
			70 DBZ 16"+ /hr Very heavy rain and hail; large hail possible.
			65 DBZ 8" to 16"/hr Very heavy rain; marble size to golf ball sized hail possible.
			60 DBZ 4" to 8"/hr Very heavy rain; marble size hail possible.
			55 DBZ 2" to 4"/hr Very heavy rain; pea to marble sized hail possible.
			50 DBZ 1" to 2"/hr Heavy rain; small granular or pea sized hail possible
			45 DBZ .50 to 1"/hr Heavy rain
			40 DBZ .50"/hr Moderate to Heavy rain
			35 DBZ .25"/hr moderate rain
			30 DBZ .10 to .175"/hr light to moderate rain
			25 DBZ .075" to .10"/hr light rain
			20 DBZ trace to .05"/hr light rain
			15 DBZ trace to .025"/hr
			10 DBZ .01" /hr to trace mist/ground clutter
			5 DBZ trace/mist/ground clutter
			0 DBZ no precipitation

Contours of echo reflectivity, also known as "VIP levels" (for Video Integrator and Processor), are plotted on the radar image as a color coded display. The colors within these contours provide an indication of the precipitation intensity and the size (or number of pixels of a certain color) depicts the areal extent of the detected precipitation. Sixteen VIP levels are related to the rainfall rate for the steady "stratiform" precipitation typical of winter time and for showery "convective" precipitation of the spring/summer/fall. Note that in very low levels, "ground clutter" (reflections off objects on the ground) may appear as precipitation to the radar at very low VIP levels.

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Why do I sometimes see what looks like a searchlight beam stuck on a radar image?

Nicknamed "death rays" by some meteorologists, these occur because the radar sometimes picks up a radar pulse from another radar, such as another NWS radar, or a ship or aircraft radar operating on the same frequency. The energy pulse from the other radar source just coincidentally lines up with the rotating sweep of the radar beam and fools the radar into thinking its seeing echoes from rain.

Just ignore these, they occur once and then disappear.

See example image at left.

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Why do I sometimes see a solid circular pattern on the radar image?

Nicknamed "nuclear explosions" by some meteorologists, these patterns occur when the radar operator places the WSR88D Doppler radar into a test or calibration mode. They are supposed to set the radar status to "offline" (in which case you'll see a message on the image saying so) but sometimes they don't, and you get the resulting circular test pattern sent to the radar distribution network.

These are rare, and usually are gone within the hour. Don't worry, the radar operators don't usually conduct these tests during storm activity.

See example image at left:

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Why is there sometimes a lot of bright red and yellow radar echoes but no rain outside ?

This is because the NWS NEXRAD radar is operating in CLEAR AIR MODE. In Clear air mode, the radar sensitivity is increased and it can detect dust, fog, temperature inversions and other atmospheric disturbances that are not precipitation related. This is sometimes called "ground clutter". While this may be useful for the trained meteorologist at times, for the most part its simply a distraction.

When the radar detects precipitation again, it automatically switches back to PRECIPITATION mode.  See the online help section on NWS radar information for more details.

NOTE: You can eliminate this problem by selecting the "always blank in clear air mode" in the DISPLAY OPTIONS section of StormPredator, and you'll not see any of these distractions. This feature is turned ON in SP by default when the program is first installed.

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I notice the rotating sweep on StormPredator is wider at the perimeter than at the center, does this have a purpose?

Yes, this is due to a phenomena of radar beams called "aspect ratio". Just like a flashlight or a lighthouse beam widens as it reaches further, so does a radar beam. This means that the radar has less resolution further away from the center. Thus you may also notice that areas or precipitation near the perimeter of the radar image appear "blocky" while the precipitation near the center appears as smaller pixels.

The StormPredator program takes this into account in the way it generates its moving sweep beam, making it wider near the perimeter and narrow at the source. You can control the beam "wideness" and the rotational speed in the Beam Control Dialog by pressing ALT-E or clicking on the button on the StormPredator main screen.

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Will Storm Predator run on?

• Windows 98SE and Windows ME? While Storm Predator will run, our opinion is that these Operating Systems are not reliable operating systems, and SP may or may not work on these operating systems because they can be so "fractured" with a variety of drivers, DLL's, and other software libraries of varying lineage. Our advice- if Storm Predator is important for you to run reliably, then use Windows 2000 or XP for trouble free operation. Windows 95 is not supported. Windows 98 original edition must be upgraded to Second Edition to run SP.
• Macintosh? Yes, when used with Microsoft Virtual PC for Macs
• Linux?  No version is currently planned for Linux
• WebTV? No. Never, ever, in a gazillion years!

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Running StormPredator on Macintosh

StormPredator can run on Macintosh when used with Microsoft Virtual PC for Macs
NOTE: either the Windows 2000 or the Windows XP emulator will work

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I can't see the Exit button or SP fills the entire screen

Sometimes at 800x600 screen size the Exit button is off the screen and covered by the Taskbar at the bottom of the screen- this happens on some video cards.

Solution: Try running at a larger screen size than 800x600 (like 1024x768) for some reason, many folks still cling to this old low resolution screen standard even if they can't fit all their programs on the screen

- or - set your Taskbar to "auto hide" Right click on the Taskbar, choose Properties, then Auto-Hide

FREE UTILITY:  If you want to quickly switch screen sizes you can also download and install
RapidRes, a free utility that can let you run StormPredator at 1024x768 and instantly switch back to 800x600 or 640x480 sizes.

Click to See More Info on RapidRes

download file: RapidResSetup.exe  310 kilobytes
                   (click to download)

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How do I put a custom basemap into StormPredator ?

You can create you own custom basemaps from StormPredator using most any Paint Program that can create PNG (Portable Network Graphic) files. Our personal preference is JASC Paint Shop Pro 7 or 8, for which we have a download link on the CD ROM menu. www.jasc.com A free 30 day trial is available, more than enough time for you to customize several maps.

You can create basemaps which are simply colored areas of land/water or you can do more elaborate schemes such as shading, drop shadows and terrain.

The trick to making it work and look right is to start with the ORIGINAL NOAA BASEMAP located in the StormPredator Installation folder which is typically

C:\Program Files\StormPredator\Images\basemaps\noaa

There you find over 600 basemaps which are installed from the CD ROM, four for each radar location.

NOTE: if you have the download version, these maps will only be present for the radar locations you have visited. SP download version extracts these maps "on the fly" when it first visits a radar site. If there is a lot of ground clutter present, then these maps may need additional cleaning up. Maps on the CD have already been cleaned of any ground clutter artifacts.

They are name coded like this:  kmaxsrbnoaa.png

This breaks down as follows:

There is a basemap for each radar product type, so for each radar location, a total of 4 maps exists. Unfortunately, we have to do it this way because the NWS did not provide for a standardizing map...each one is slightly different...meaning that to fully customize a radar location basemap, you'll have to do 4 maps.

The maps provided by the NWS are not perfect, and many contain missing pixels in state/county/water borders. Most of the work involved here is in fixing missing pixels in borders so that you can fill in land and water areas in different colors without getting a "leak" when attempting a flood fill.

Note that StormPredator offers a map customizing service. Contact us at support@strompredator.com or at 530-899-8434 for a quote. Prices start at $49.95 each

But for those that wish to do it yourselves, we have provided a single sample custom map for kamx short range base reflectivity mode  in the \CustomMaps\CustomizedKAMX\ folder on the StormPredator CD ROM so that you can see what results can be achieved with some simple modifications.

To see how the map looks in SP, simply copy it to your

C:\Program Files\StormPredator\Images\basemaps\custom folder and rename it kamxsrbcstm.png

And make sure you have selected Miami, FL in the Site Options and also Short Range, Base Reflectivity

Then choose "use custom 24 bit basemaps" in the SP "display options" and you'll see it load.

To see what it looks like now - a small sample image is show below, click for a larger image.

To customize a base map with a paint program:

1. Copy the 4 original noaa basemaps for the radar location you want to customize to a temporary work folder
2. Convert all 4 maps from 8  it to 24 bit color and save them
3. Use magnify tool to locate gaps on borders- usually the are a single pixel
4. Using the  line tool, set your draw color to white (255,255,255) and  turn off anti-aliasing
5. Use line tool to fix holes in state borders, extend borders to top and sides of screen of screen if need be. Don't worry if they don't match geographically, they can't be seen because they will be outside the SP scope ring
6. Choose a land color (122,82,18 is a good brown for land)
7. Start filling in land areas, test a step at a time with fills, use the Undo feature in the paint program if "leaks" occur, then fix the border, and try again until the fill works.
8. Fill in holes inside the map city labels, such as in "o" "a" "d" " etc...
9. Note for areas where lakes/rivers/oceans occur, fill them with blue, or a shade from top to bottom.
10. Save the completed image as a 24 bit PNG file to the C:\Program Files\StormPredator\Images\basemaps\custom folder and rename it so that it has "cstm" on the end rather than "noaa"

Some tricks to note:

To get drop shadows on city names- its important that the city name and color not change at all. To do this simply use the "select" tool to select the white letters of the city name, then apply the drop shadow effect- usually offset to the right and down 3 pixels with a 75% opacity and a slight blurring looks good. You can see this effect in the sample map kamxsrbcstm3.png we provided on the CD-ROM

To make shaded land and water- Set the foreground color to be a darker color than the one you have chosen for the background color, then choose the "fill color" to be a gradient, and the gradient type foreground-background. Then proceed to fill your land or water masses...you may have to seed several fill points to get all enclosed areas of the map, don't forget to fill inside city names too!

To add road symbols- from the "bonus artwork" section of the CD ROM, copy the symbol you need to the work folder, then using the text tool, put the road number into the symbol with white (255,255,255). Then change the background color surrounding the road symbol Reduce the road symbol to match the color of the earth tone you selected, and then reduce the size to match the scale you want. Copy and Paste on the map with the background earth tone color set to be "transparent" and it will blend in perfectly and be anti-aliased against the earth tone background.

There are many more ways to customize the basemaps- the key thing to remember is that the roads, county borders, state borders, and water boundaries must be kept exactly the same in the custom basemap as in the original NOAA maps.

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FAQs prepared by Anthony Watts, Meteorologist.
Copyright © 2003  IntelliWeather. All rights reserved.
Revised: July 09, 2006