🌪️ Tornadoes, Downbursts, and Microbursts: What’s the Difference and How to Spot Them on Radar

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When severe weather strikes, tornadoes often get the most attention. But they are not the only dangerous wind threat. Downbursts and microbursts can cause similar damage, sometimes without warning and without any rotation. Understanding how these wind events form and how they appear on radar can help you stay safe and informed using IW Pro. Keep in mind that radar scans at an angle above ground, so what you see may be occurring hundreds or even thousands of metres up.

🌪️ Tornado

A tornado is a rotating column of air that connects a thunderstorm to the ground. Tornadoes form in environments with strong wind shear and are most commonly associated with supercell thunderstorms.

What to look for on radar:

  • Reflectivity: A hook echo is often present. This curved shape on the southern side of a storm shows rain wrapping around a strong updraft.

  • Velocity: Look for a tight couplet of red and green pixels close together. This pattern indicates strong rotation and is known as a velocity couplet.

Important note: Radar scans the atmosphere at an angle, so rotation shown on velocity data may be happening above the ground. While not every velocity couplet leads to a tornado, strong rotation near the surface is a serious warning sign.

📸 Example: EF-4 Tornado near Didsbury, Alberta (July 1, 2023)
This image shows a clear hook echo on reflectivity and a tight inbound/outbound velocity couplet. The tornado was confirmed by the Northern Tornadoes Project.
🔗 Read the full damage survey

Didsbury EF4 Tornado July 1 2023

💨 Downburst

A downburst occurs when a powerful column of air descends from a thunderstorm and hits the ground, spreading outward in all directions. These straight-line winds can cause widespread damage without any rotation.

What to look for on radar:

  • Reflectivity: Often shows a bow echo — a bulging line of storms where the wind is pushing outward.

  • Velocity: Displays a divergent wind pattern, with air moving away from a central point rather than rotating.

📸 Example: Downburst near Spencerville, Ontario (June 24, 2025)
Velocity radar shows two separate areas of outward-spreading wind with no rotation, consistent with a large downburst.

Two areas circled that show Classical signs of a Downburst

📸 Example: Downburst near South Branch, Ontario (June 24, 2025)
This storm produced a bow echo on reflectivity and strong divergence on velocity, with measured wind speeds over 100 km/h. There was no evidence of rotation. This is the stronger (the one on the left) of the two signatures in the above example.

Downburst Radar Signature near South Branch

🌬️ Microburst

A microburst is a smaller, more intense type of downburst, typically less than 4 kilometers wide. Microbursts can cause major damage in a small area and are especially hazardous to aircraft.

What to look for on radar:

  • Reflectivity: May not show much detail due to the small scale.

  • Velocity: Sometimes shows a very localized patch of diverging winds, but these events are often only confirmed after damage reports.

🛰️ Understanding Radar Velocity

Velocity radar shows the motion of air above the surface, not at ground level. Depending on how far you are from the radar site, the beam may be scanning thousands of metres up. This means:

  • Not all rotation seen on radar reaches the ground.

  • Not all high wind speeds aloft result in surface damage.

  • However, strong radar signals combined with other data can help identify real threats.

This is why it is important to interpret radar in context and watch for warning signs like wind divergence, rotation, or storm structure.

⚠️ Quick Comparison

cHart comparing Tornado DownBurst and MicroBurst

⚠️ Microbursts often leave little to no clear radar signature at the time of occurrence. Their small size and brief duration mean they are usually identified after damage reports or post-event analysis. Watch for strong divergence on velocity, but also consider surrounding conditions like collapsing storm cores.

📡 How IW Pro Radar Products Help Detect Tornadoes, Downbursts, and Microbursts

In addition to standard reflectivity and velocity products, IW Pro also offers advanced dual-polarization radar tools. These products provide more detail about what's happening inside a storm, including the type, shape, and motion of precipitation. While tornadoes often show clear signatures across several radar layers, microbursts and downbursts can be more subtle. The chart below explains what each radar product measures, how it helps identify different wind events, and when it’s most useful.

Description of different the Different products available in IW PRO

🌀 Tornado Clues (IW Pro):

  • Velocity: Tight couplet (red/green side by side)

  • Reflectivity: Hook echo

  • CC: Drop below ~0.85 = debris

  • ZDR: Low ZDR with low CC and high reflectivity = debris

  • KDP: High values = intense rain or hail core

💨 Downburst / Microburst Clues (IW Pro):

  • Velocity: Outward/divergent wind pattern near surface

  • Reflectivity: Strong core, sometimes collapsing

  • ZDR: Sudden changes can suggest melting hail or bursts of rain

  • KDP: Brief spike may suggest dense rain shaft

  • CC: Usually normal, but a sudden dip might appear if mixed particles (hail, rain) are ejected downward

⚠️ Microbursts often lack clear radar signatures, so the absence of rotation + burst pattern in velocity is often the main clue. Dual-pol products are supporting evidence, not primary tools here.

🎥 Learn More: Visual Explanations of Tornadoes, Downbursts, and Microbursts

For a deeper understanding of how these wind events form and how to identify them using radar these two short videos offer excellent animations, real-world examples, and clear radar visuals:

📺 Tornado vs. Downburst vs. Microburst
A clear side-by-side explanation with radar examples and damage comparisons
🔗 Watch on YouTube

📺 Microburst vs. Tornado: What's the Difference?
Highlights the key differences in structure, impact, and radar appearance
🔗 Watch on YouTube

These videos are a great supplement to the radar tools available in IW Pro and help you recognize what to look for before dangerous winds reach the ground.

🌦 Final Thoughts

Tornadoes, downbursts, and microbursts are all serious threats, but they behave differently and require different radar clues to detect. With IW Pro's full radar suite including velocity, reflectivity, and dual-pol products you have the tools to better understand what you're seeing on radar and stay ahead of severe weather.

If you found this helpful, share it with friends or family who follow storms or use IW Pro.

Introduction to Instant Weather Pro

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Welcome to Instant Weather Pro, our most powerful radar platform yet. It is built for those who want more control, more detail, and more precision when tracking the weather across Canada and the U.S.

Following our official partnership with the Northern Tornadoes Project at Western University, their team asked us to build a state-of-the-art radar suite to help track and validate tornadoes and hail across Canada. The result is a professional-grade radar system that is now available through IW Pro.

IW Pro is a next-generation radar platform offering the same high-resolution data trusted by meteorologists. Whether you're a storm spotter, first responder, outdoor event planner, farmer, or weather enthusiast, it delivers the tools you need in an intuitive, mobile-friendly interface. It also works seamlessly on desktop and laptop, allowing you to open multiple windows for side-by-side analysis or to track different storms simultaneously.

We are also planning to launch IW Pro as a subscription tier inside our popular Instant Weather app. All current subscribers will receive access to the app version as well as the website version at no additional cost.

Instant Weather Pro on iPad

🔍 What Makes IW Pro Different

Most weather apps use a "mosaic radar" view, which is a blended image from multiple radar stations. While that is great for getting a broad picture, it smooths out important details.

With Instant Weather Pro, you can:

- View individual radar stations directly and not just the combined mosaic.

- Choose from multiple radar products to get different types of data.

- Control the elevation angle (tilt) to see different slices of the atmosphere.

- Compare radar products using Dual Mode or Split Mode.

- Enjoy ad-free browsing with a faster and cleaner experience.

- Track weather using desktop, tablet, or mobile all through your browser.

🛰️ Compare Radar Products: Dual and Split Modes

Instant Weather Pro offers two powerful ways to compare radar products, helping it stand out from many other tools on the market.

🔄 Dual Mode (Side-by-Side)

Use Dual Mode to view two radar products at the same time, side by side.

- Great for tracking how features like wind rotation (Velocity) line up with precipitation patterns (Reflectivity).

- You can zoom and pan both views together to follow the storm from multiple perspectives.

Dual Mode on a laptop, showing Reflectivity (left) and Velocity (right) from the Didsbury, AB tornado (EF4) on July 1, 2023.

🧭 Split Mode (Swipe Slider)

Split Mode lets you compare two radar products in the same view using a draggable slider.

- Move the slider left or right to reveal one product on one side and the other on the opposite side.

- Unlike side-by-side views, everything stays perfectly aligned, making it easy to see exactly where features overlap.

- Ideal for quickly checking if a hook echo on Reflectivity lines up with rotation on Velocity.

Whether you prefer a side-by-side layout or a swipe-to-compare approach, IW Pro gives you the flexibility to analyze radar data your way.

Below is the Didsbury, AB tornado displayed in Split Mode. This iPhone-recorded video demonstrates how you can swipe between Reflectivity and Velocity radar products to observe how storm features align.

🛰️ Radar Products Available

IW Pro lets you switch between several advanced radar products, including:

- Reflectivity – See the intensity of precipitation.

- Velocity – Measure wind moving toward or away from the radar (great for spotting rotation).

- Correlation Coefficient, Differential Reflectivity, and Specific Differential Phase – Advanced tools used by weather experts to detect hail, debris, and rainfall structure.

Not sure which product to use? We'll explain each of these in upcoming posts to help you get the most out of them.

🕒 Access Past Radar with Historical Data

Missed a storm? No problem.

Instant Weather Pro gives you access to historical radar data, so you can revisit and review previous weather events which makes it ideal for storm analysis, research, or just satisfying your curiosity.

- Scroll through archived radar loops for past days.

- Analyze storms in detail using different radar products.

- Perfect for training, educational use, or verifying what happened.

This feature also helps us create clear blog visuals, even when the weather is quiet. Many of the radar examples in this blog were captured from past events.

💡 Customization at Your Fingertips

You can fine-tune your radar view by:

- Changing radar products with one click.

- Adjusting the elevation angle (tilt) for surface or higher-level scans.

- Choosing radar loop speed or stepping frame by frame.

- Switching color schemes (like green/red velocity view).

💰 Subscription and Access
IW Pro is currently available for $99.99/year through our website.

Please note: This is our current rate and is subject to change in the future.

What’s coming soon:

  • Monthly and app-based subscription options

  • Additional tiers to match your usage needs.

We recommend signing up on our website for the best value. App store purchases include additional platform fees.

🚀 Ready to Get Started?

Ready to explore advanced radar features? Subscribe to Instant Weather Pro today and take your virtual storm chasing to the next level.

And be sure to check back here on the blog as we’re building a growing library of helpful tips to make the most of your IW Pro experience!

Have questions or feature suggestions? Let us know as we're building IW Pro with your feedback in mind.

🛠️ IW Pro Settings Overview (last reviewed May 2025)

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To open the Settings menu, tap or click the three bars in the upper-left corner of the screen.
Here’s a description of each setting. Some have recommended values, but many can be toggled based on your needs. We often switch them on and off during active use.

IW Pro settings

🔧 Settings Breakdown

Layer Opacity
Adjusts the transparency of the radar layer on the map.

Live Mode
When enabled, IW Pro auto-loads new radar frames as they become available.

Velocity Color

  • Velocity 1: Red/blue (Environment Canada standard)

  • Velocity 2: Red/green (more common in U.S.-based radar apps)

NEW – Velocity & Measurement Format
Choose between mph/kph. This setting also determines the units for the measurement tool (mi or km).

Radar Placement Accuracy

  • Recommended: 11 for most devices

  • Use 8 for slower performance

Labels and Boundaries
Toggle on or off to show location names and boundaries.

Time Display
Choose between 12-hour or 24-hour time format.

Canadian Radar Noise Reduction

  • On: Reduces radar interference spikes (“laser beams”)

  • Off: Shows additional features like hail spikes and faint outflow boundaries

Hail Size Estimation
This feature may not be available in the current production version. It was visible in recent builds but has been temporarily removed as we rolled back to a previous version due to performance issues. It may return in a future update.

Lightning Data
Toggle on to view real-time lightning strike locations on the map.

Mosaic Radar Layer
Shows the combined radar mosaic when no specific radar station is selected.
Tip: We recommend also turning off radar icons when using this layer.

NEW – IW StormRisk (Beta)
Displays IW’s experimental storm risk overlay.
[See this blog post for more details.]

NEW – Thunderstorm Forecasts
Shows Environment Canada’s “Thunderstorm Outlooks.”
Choose a time period and opacity level.
[See this blog post for details.]

Alerts
Turn this on to display alerts on the map. You can customize which types of alerts to show:

  • ECCC Alerts (from Environment Canada)

  • IW Instant Updates (our own real-time updates)

  • U.S. Alerts (from U.S. National Weather Service)

    You can also choose which specific alert types appear:

  • Instant Updates

  • Warnings

  • Watches

  • Statements and Advisories

  • U.S. Alerts
    Note: You can mix and match alert types and sources based on your preferences.

💡 Tip

To quickly reload radar data, toggle between Single, Split, and Dual modes.

Environment Canada's "Thunderstorm Outlooks"

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Environment Canada's official "Thunderstorm Outlooks" have been integrated into Instant Weather PRO!

Day 1, Night 1, Day 2 and Day 3 are all be included with full details when you select the forecast on the map.

Screenshot of ECCC Thunderstorm Forecast

You can select a day or turn it off in rendering parameters. You can also specify the opacity.

Here are a couple more examples including a funnel cloud risk.

IW StormRisk storm track arrows and colour key

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The StormRisk storm track arrows have been added so that you can see the predicted direction of travel of the storm(s).

With the radar turned on:

Here are some examples of the colours of the outlines with the Total Severe Risk percentages. Note that the thickness of the outline also increases when the risk increases as well. You can see that in some of the examples where there is another outline present in the screenshots (24-48).

Note that the black colour for greater than 85% is a bug. You will not be able to see against the black map but it will show up well when radar is on.

IW StormRisk is live

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IW StormRisk is live for all IW Pro users and combined alert polygons are live in Canada as well!

To turn on IW StormRisk just click on the menu (three bars at the top left) and click to turn it on:

IW StormRisk only works as far north as 51N (basically just south of Calgary) but we have plans to extend it further north to 55N, which will include locations like Saskatoon and Edmonton.

The thickness of the outline is related to the risk level as well as the colour of the outline is related to the type of risks. Here are some examples:

Look for irregular shapes and click on them to see the IW StormRisk:

Mosaic Radar Layer

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You can now utilize the Mosaic Radar Layer to gain a comprehensive view of weather systems. This feature allows you to zoom in on specific storms of interest for a detailed analysis using IW Pro.

Turn it on in Rendering Parameters:

The Mosiac Radar Layer will be visible if no radar stations are selected. Below alerts and radar icons are turned off:

Below alerts are turned on:

Zoomed into a tornado warned storm:

Selected a radar station and Mosaic Radar Layer is turned off:

Note: The Mosaic Radar Layer is not automatically updated.