1. Introduction

2. StormLab Interface

• The Radar Selection Tree
• The Product Buttons/Descriptions
• The Toolbar  

3. Customization

• Default Program Options
• Storm Cell Alarm Settings
• Color Table Editor

4. The Radar Display Window

• The Data Legend
• Keyboard Shortcuts
• Storm Cell Table & StormTracker Plus Pathcast

5. Auto-Download Engine

6. Image Save/Upload Utility

7. StormLab's GPS StormChaser (Professional)

8. Frequently Asked Questions

StormLab©  is the FIRST publicly available software to take advantage of the full National Weather Service Doppler radar imagery suite. StormLab© turns any internet connection into a unique and comprehensive display system for National Weather Service Doppler radars. With access to every WSR-88D radar in the entire US, you will have instant access to reflectivity, velocity, storm relative velocity, VAD Wind Profiles, precipitation estimates, storm cell data, and MUCH more. StormLab's© full-featured interface including looping, zooming, and overlays of cities, county names, highways, mesocyclones, tornado vortex signatures, and much more! Everything is customizable, right down to the color tables used to display the images. Use the auto-ingest engine to store radar data from interesting events while you're away, and then go back to view it at anytime! We guarantee this will blow away any radar software or internet viewer you've ever seen! Why settle for anything less than software written by meteorologists.

When a radar beam is sent out, reflectivity is simply the power returned back to the radar from hydrometeors (rain, snow, hail, bugs, birds, even vehicles on highways!) This is the image that you typically see on TV. Unlike conventional radars developed many decades ago, the Doppler Radar has the capability to provide much much more information. Do not be overwhelmed, but remember that this is not a radar tutorial on how to interpret the images available. Many of these products require countless hours of skilled training and experience to interpret, and therefore should NOT be used to second-guess warnings issued by your local National Weather Service - They are the experts! Remember that in addition to whirling around 360 degrees (a full circle) the radar also tilts upward to provide a 3-Dimensional slices through the atmosphere. Therefore, several cuts/slices/tilts of reflectivity and velocity products are available to the public. Additional products will likely be added over time.  For more information on interpreting radar imagery, you may find useful tips here:

Here is a brief description of each product:

Reflectivity - The amount of power returned back to the radar from airborne particles, insects   or other objects. Units are logarithmic (dBZ). Values can range from -28 to over 75, and different scales may be used depending on whether the radar is in clear air or precipitation/storm mode. Particular values do not necessarily correspond to different precipitation types (rain, sleet, snow, etc...) and many atmospheric conditions can provide a variety of phenomena to appear.

Composite (Reflectivity) - Same as above, except instead of viewing the reflectivity at one radar tilt, this image displays the MAXIMUM dBZ value at any elevation tilt for a given location. Basically, if you were standing 30 miles east of the radar, and above you, the radar sampled dBZ values of 5, 25, 30, 34, 52, 40, 37, and 22 at different heights...the image would display 52 dBZ for your location. Used to show the most intense storms and hail cores aloft. Used by radar operators as more of a "catch all" as it is the last product received per volume scan (one complete radar sweep of the atmosphere). This image is also accompanied for the Storm Cell Attributes Table. Click here for more info.

Velocity - Doppler radar can detect winds blowing toward or away from the radar, called Radial Velocity. NOTE: the radar can again only detect that portion of the wind which is blowing along the radar beam. For example, if you are looking south from the radar, and the wind was blowing from the west or east at even 80 mph, the radar would see 0 knots because the wind is blowing perpendicular to the beam. Also note that the radar beam extends higher and higher the farther you go from the radar. Novice users often mistake high winds aloft (fairly common) for strong winds at the surface. Velocity imagery can take years of experience to master and can fool even the most experienced.

SRM - Stands for "Storm Relative Map". Same as above except the motion of the storms (entered by the radar operator) is subtracted out. Therefore, the wind field relative to a storm of interest can be observed. This is used to detect storm scale rotation or other features which could signify the onset of very large hail, a downburst, or possibly a tornado. 

Precipitation - A great benefit of Doppler radar is its ability to estimate fallen precipitation, in order to fill in the holes left by observation networks, automated rain gages, and other sources of data. Measured in inches, Doppler Radar can estimate precipitation that has fallen over the past hour, three hours, and storm total. Note the beginning and ending times on the storm total imagery. The radar requires several hours of no precipitation before resetting, and areas that receive a lot of rainfall can have this image piling up for days if not weeks! Also note that precipitation can be severely overestimated due to storms which contain hail and the freezing level, as partially melted ice returns an extremely high reflectivity.

Layer Reflectivity Maximum - More of a use for pilots, this product is a coarse resolution image (4km) which provide the maximum reflectivity at different layers in the atmosphere: lower, middle and upper. 

VIL - Vertically Integrated Liquid. A coarse resolution image that is basically a measure of the total liquid in a vertical column, in units kilograms per square meter. Most used to identify storms with heavy rainfall or large hail. Can also be used in combination with other products to predict the onset of wind damage.

Echo Tops - Simply image depicting the estimate of storm cloud tops. Note that depending on the tilt of the radar beam and distance from the radar, these can be severely over or under-estimated on the order of 5-10,000 feet or more.

88D Text Message - In the event of a radar outage, software upgrade, or other significant mode change, the NWS in charge of that radar will send out a message explaining the problem or change. 

The toolbar provides quick access to StormLab's© most used features. Let's go through each one of these. Note that you can move your mouse over any toolbar item for a brief description of it's functionality.

	Loads the auto-archive dialog to view past radar events.
	Checks for new data for the active radar window.
	Loads the Save/Auto-Upload Utility to save/upload a screen shot of an active radar image or the entire StormLab window.
	Sends a hardcopy of the active radar window to the printer. (Black/white inverted to save ink)
	Used to step-through radar loops. First, back 1 frame, forward 1 frame, and most current.
	Toggles to loop for the active window on or off.
	Loads the image properties window. Click here for more info.
	Loads the loop properties window. Click here for more info.
	Loads the Auto-FTP Engine. Click here for more info.
	Loads the Storm Cell Attribute Alarm Settings. Click here for more info.
	Clears the active radar display.
	Toggles among active radar display windows.
	Tells StormLab© how many images to load into the radar loop. Click "Load Single Frame" if you would like to load the latest imager instead of a loop.

Also unique to StormLab© is access to the Storm Cell Information Table that accompanies the Composite Reflectivity Product.  The WSR-88D Doppler Radar includes a number of mathematical algorithms that take raw radar data and compute a "best guess" estimate for valuable storm information such as hail size, storm rotation, and tornado potential.

It is imperative to realize that this output is ONLY mathematical computations of raw reflectivity and velocity data, and should not be used to second-guess the National Weather Service warning forecaster.

In the Storm Cell Table example below, each storm cell on the radar screen (a customized overlay) is given a letter/number ID such as "V7". Simply use the up/down buttons on the options menu to change the color-coded thresholds for these tables, ranging from white (minor threat) to yellow (moderate threat) to red (major threat).

You can also configure an audio alarm to sound when any of these values enter the "red" zone. Note to avoid sounds going off every 20 seconds, an alarm will only be sounded if the previous scan for that radar site did NOT exceed the red threshold value.

Upon successfully loading a radar image or loop, you will see a window containing the radar loop, a legend and a status bar. The loop, speed, and other features can be controlled with the toolbar at the top, or by keyboard shortcuts listed below. 

• If you have Data Sampling turned on in the overlays, you can get read outs as you move your mouse over the radar image, including the value of the data, how far that point is from the radar, and the height at which the radar beam is intersecting that point (above ground level). All these are very useful in diagnosing the true intensity of a storm. 

• If you are displaying a composite reflectivity product and have checked the Storm Cell Overlay in the legends, you can see the storm cell IDs, any mesocyclones (yellow circles) detected by radar, any TVSs detected by radar (inverted red triangles), and the storm's projected path for each 15 minutes out through the next hour (white line with dots). All this data comes from the Storm Cell Information table that also loads with this product. Click here for more info. 

• Lastly, zooming is SIMPLE with StormLab. A left mouse click zooms in 200% at that point, a right click zooms out 200% at that point. You can zoom in up to 1600%! 

• With StormLab© Professional, surface observations (METARs) as well as tornado, severe thunderstorm, and flash flood warnings can also be plotted and sampled in real-time.

For those of you who prefer not to use that invention called a mouse, we have added some keyboard shortcuts for radar viewing:

If you click the floppy disk icon in the toolbar or "Save/Upload Utility" under the Plug-ins menu, you will be greeted with the above window. This utility is a rather nifty program that allows you to do screen captures of an active radar image or of the entire StormLab window (to compare images). You can then upload these images to your webserver. First, select the format that you would like to use. StormLab supports jpeg and png format. We really like png's small file sizes while maintaining an image quality far superior to .jpg Next, select the type of screen capture you'd like to do. Next, enter in a .jpg filename to store the image as on your hard drive (or use the browse button). If you do not specify a directory (e.g. radar.jpg), the program will default to the StormLab directory. If you would like to upload the image to your webserver, check the "Upload Image To Web Server" box and enter in the appropriate information. Click "GO!" and that's it!

The new and improved Save Utility now provides an "Auto Upload" feature. If you check this box, StormLab will automatically create screen captures for each radar loop you have loaded when new images are received, and then upload them to your server. A detailed explanation are provided on the utility interface. NOTE: These screen captures work just like any other Windows screen capture. StormLab MUST be on top in order to capture the StormLab imagery. We're sure you don't want to see email or other private information uploaded to your website for the world to see :)

Why do I receive an error about unzip32.dll when I first run the program?

• When StormLab first runs, it will attempt to automatically install the county and highway maps into their appropriate directories. For some reason your version of unzip32.dll is out of date. To fix this problem you can either delete unzip32.dll from C:\Windows\System or C:\WinNT\System32 and reinstall StormLab...or use a free software program like WinZip to manually unzip the basemaps.zip file into the "...\StormLab\Basemaps" subdirectory and the highways.zip file into the "...\StormLab\Highways" subdirectory.

How do I find the nearest radar site to my location?

• Under the File menu, click "Find Nearest Radar..."

When I load a radar image, it takes up only about 1/3rd of the black window that is supposed to hold it. I've also noticed that the buttons don't entirely fit inside the toolbar at the top of the main window.

• In rare cases, especially true on laptops, the computer comes incorrectly with the default setting for large screen fonts, which can make many programs appear goofy (even though this wasn't intended). To remedy this problem, right click on the Windows desktop and choose "Properties". When the Display Properties window pops up, click the Settings Tab. Now click the "Advanced..." button in the lower right. There should be a General tab. If it's not already selected, click it. Change the font size from large fonts to small fonts (normal size 96 dpi). Click OK and you are good to go.

NOTE: you can always adjust your Windows font size in the Display Properties window by clicking on the Appearance tab instead of Settings.

When I load a radar image, I receive a grey-ish screen with some of the overlays.

• Please make sure that your computer is running in 16-bit color more or higher. This will ensure that you have a sufficient color table to match the ones loaded on your radar screen.

When I load a radar image, I receive a black screen with no data.

• Chances are, you previously closed down StormLab incorrectly, leaving files that should have been deleted. Close that radar image and reload it. All should appear just normal the second go-around. The other possibility is that you do not have a basemap or highway map installed for that radar site. Please contact us if reloading the radar data doesn't fix the problem.

When looping radar imagery, it seems to take a lot of processing time between each image. Increasing the loop speed doesn't seem to help either.

• We continue to improve the processing speed of the software, and have had great success, even on a low end Pentium II with 64mb of RAM. However, since this program uses raw data to give you the most customization, the faster the computer you have, the better. Make sure that your computer is running in at least 16-bit color mode.

Why does the radar date/time stamp always seem a few minutes slow?

• First, make sure that your computer clock has been checked against the Naval Observatory. OK, now the time/date stamp used in StormLab is correctly attributed to the time/date when the radar began that volume scan. This way, you know when the data you're seeing actually occurred. After the scan is complete, the radar transmits the raw data in a priority order. Therefore, the time stamp on new incoming data may be 1 to 5 minutes old, but we assure you that you are receiving it within seconds of when it was transmitted. All products from that radar scan will have the same date/time stamp. Got it? Good!

What do POH (Probability of hail) and POSH (Probability of Severe Hail) represent?

• Doppler radar is capable of doing quite a bit of number crunching in addition to displaying the radar products. Supplied with the height of the freezing level and the -20C level, the radar can use the reflectivity data and other products to compute the chance that hail will fall within a given storm cell. The algorithms are rather rudimentary and should be taken with a grain of salt, however if you see 100% chance with a max hail size of 3.00" in the table...you better take cover! The probability of severe hail is the chance of hail >= 3/4 of an inch in diameter. The max hail size is the radar's estimate of the largest possible hail stone that could be contained within that thunderstorm cell. Note there are many factors that can greatly alter these values, and there are other techniques radar operators use to estimate hail. It is common for the radar to compute a chance of severe hail in the storm, and no severe thunderstorm warning is required. 

What is a MESO (Mesocyclone)?

• A storm-scale region of rotation, typically around 2-6 miles in diameter typically found in supercell thunderstorms. The circulation of a mesocyclone covers an area much larger than the tornado that may develop within it. Properly used, mesocyclone is a radar term; it is defined as a rotation signature appearing on Doppler radar that meets specific criteria for magnitude, vertical depth, and duration. Therefore, a mesocyclone should not be considered a visually-observable phenomenon (although visual evidence of rotation, such as curved inflow bands, may imply the presence of a mesocyclone). The algorithms used for computing mesocyclones are EXTREMELY sensitive, and the doppler radar may frequently trigger false mesocyclones along squall lines, fronts, and other boundaries that result in sharp wind shifts. Again, a mesocyclone indicated by radar does NOT necessarily indicate a severe thunderstorm, and radar operators will often look deeply into the velocity imagery to assess the significance of mesocyclones. Those persistent with time and location need to be watched closely.   

• Depending on the depth and strength of the mesocyclone, you may see the following abbreviations in the storm cell table: UNCO (uncorrelated shear...typically weak and insignificant), 3DCO (3D correlated shear...changes in wind speed/height are found vertically at two radar slices)...and MESO (Mesocyclone...deep rotation found vertically at 3 or more slices).

What is a TVS (Tornado Vortex Signature)? Why isn't there a tornado warning in effect for my county when I see one of these?

• Doppler radar signature in the radial velocity field indicating intense, concentrated rotation - more so than a mesocyclone. Like the mesocyclone, specific criteria involving strength, vertical depth, and time continuity must be met in order for a signature to become a TVS. Existence of a TVS strongly increases the probability of tornado occurrence, but does not guarantee it. A TVS is not a visually observable feature. In some instances, the TVS algorithm can also be triggered along squall lines, fronts, or even severe thunderstorms whose rotation is still well above the surface. Therefore, it is certainly possible to see a TVS on Doppler radar imagery without a tornado warning being issued. Those storms that have persistent TVSs associated with them for several radar scans need to be watched closely.