How-To Guide for StormView Radar

Welcome to the all-new Interactive StormView Radar! This radar tool is optimized to help you track storms. Use the buttons and check box options to turn on and off the different features available to you, and be sure to try out our new features – distance, probe, and tracker!

For more help, click on the links to the left or check out this video tutorial.

Zoom In / Zoom Out

Click “Enable Zoom” button. Left click on map to zoom in. Continue clicking to zoom in further until a pre-defined maximum zoom is reached. Click “ZOOM OUT” to return to full view.


The Radar button, already selected, is the standard radar display with the various intensities of precipitation represented by different colors.

The intensity is measured in units called dBZ. The scale is on the bottom and ranges from light precipitation represented by greens to more intense precipitation represented by the reds and pinks. The most extreme precipitation intensity is white.


This button changes the radar imagery to detect winter participation like freezing rain, sleet and snow. The legend on the bottom indicates the winter precipitation type.

This highly advanced feature allows you to track winter storms and monitor the type of precipitation falling in a particular area.


The Rainfall button displays the total precipitation across the region. You will note the scale on the bottom changes to a color table representing amounts of rainfall from zero to over 11 inches.

Storm Track

This will overlay a storm track on every significant storm. The line extending from the storm points in the direction of motion, and the end of the line gives you an idea of where the storm will be in one hour. Thus, if a line passes over your hometown, you can expect the storm’s arrival within an hour.


The Hail button displays the results of an extremely sophisticated program that calculates the maximum potential size of hail stones in a given storm.

As you can see in the scale on the left-hand side of the radar window, a small white ball icon is plotted when the radar detects small hail. A slightly larger white ball indicates larger hail, with the maximum hail in inches inside the ball.


The Rotation button shows the location of mesocyclones, or deep rotation within a thunderstorm. Though not every mesocyclone will produce a tornado, research shows that about one in three will. But nearly every significant tornado is associated with a mesocyclone!

Also worthy of note is the fact that the long-lived mesocyclones are almost always associated with either hail or high winds.

Intense Rotation

A TVS, or Tornado Vortex Signature (indicated by the “Intense Rotation” icon), means the radar has found an unusually strong or even violent rotation within the lower-levels of a storm. A TVS is NOT a guarantee of a tornado touchdown, but the probability of one occurring has gone up significantly, especially if it follows a long-lived mesocylone.

When you hear a “Tornado has been indicated by Radar,” a TVS is often what is being seen. Also of note, sometimes bad radar data will trigger a TVS to be displayed, which in this case is an error.

Watches-Warnings-Advisories (WWA)

If you turn on Watches-Warnings-Advisories, many types of WWA’s issued by the National Weather Service will appear on the display. Clicking on the shaded WWA will open a new window with the full text of that particular alert.

Severe Warnings

If you turn on Severe Warnings, you will see any Severe Thunderstorm, Tornado, or Flash Flood Warnings issued by the National Weather Service.

You will notice that the severe weather areas are not just simply outlines of the warned counties. These warnings are plotted with precise latitude and longitude points that reveal which parts of the warned counties are expected to experience severe weather conditions.


Click this option to identify cities and major roads on the map.

Latest Temps

Click this option to plot the most recent temperatures from major reporting locations across the region.

Navigation Bar

Across the top of the radar display are a series of buttons with different regions named. Click any of these buttons for a “quick zoom” to that region on the map. “Regional” is the default, and furthest out, zoom level.


Click this button to activate the distance calculator. Then, simply click the starting point on the map, then drag your mouse in any direction for a real-time readout of the distance from the starting point. Click “Hide Distance” when finished.


Click this button to query the radar data for actual values (rainfall rates, precipitation type, or total precipitation depending on which mode you are displaying – radar, winterize, or rainfall, respectively). Probe works best when the radar animation is stopped. Click “Hide Probe” when finished.


The Tracker button can be very useful in predicting about when a storm will arrive at certain locations. Using a time-distance calculation, estimated times of arrival are plotted for storms you select.

First click the Tracker button. The radar loop will stop on the first image in the sequence and you will be asked to “Click on target’s initial position.” Click the leading edge of the cell of interest. A white + sign is plotted and the image changes to the last frame in the loop. You are asked to “Click on target’s final position.” Find the leading edge of the same storm and click it, then hold your mouse still. Another white + sign appears.

The display will tell you what direction and speed the storm is moving, as well as provide ETA’s for that storm if it continues at the same speed. You may also move the cursor around on the screen to other storms of interest for ETA’s from those storms (provided they are moving the same direction and speed). Click “Hide Tracker” when you are finished tracking the storms.