Breakdown: What is a “Convective Outlook” from the Storm Prediction Center and why do they matter?

Published: Dec. 29, 2021 at 11:16 AM CST
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MEMPHIS, Tenn. (WMC) - Severe weather is a common occurrence in the Mid-South, and when it comes to strong and severe storms, understanding what the colors and text means could better help you prepare for incoming severe weather.

When severe weather is on the way, the First Alert Weather Team will show you graphics from the Storm Prediction Center (SPC). Below is an EXAMPLE:

Example of a convective outlook from NOAA's Storm Prediction Center. 
Example of a convective outlook from NOAA's Storm Prediction Center. **NOT A CURRENT FORECAST**(WMC)

The SPC is located in Norman, Oklahoma and is part of the National Weather Service (NWS) and the National Centers for Environmental Prediction (NCEP).

The SPC is the trusted source for the prediction of tornadoes and other high-impact hazardous weather.

There are five risk categories: marginal, slight, enhanced, moderate, and high.

  • The SPC also issues General Thunderstorms. This is colored in a light green. This means that no severe storms are expected. Lightning and flooding threats will exist with all thunderstorms.
Understanding categories from The Storm Prediction Center
Understanding categories from The Storm Prediction Center(SPC)

1 - Marginal Risk: Isolated severe thunderstorms are possible.

A marginal risk for severe weather means that isolated severe thunderstorms are possible but are limited in coverage, intensity, or duration. Under a marginal risk, damaging winds and large hail are possible, but only in a few spots. An isolated tornado can also occur but the chance is very low. Our area commonly gets placed under this category during severe weather season.

2- Slight Risk: Scattered severe thunderstorms possible.

A slight risk for severe weather means that scattered severe storms are possible but typically are short-lived and not widespread. Intense severe thunderstorms are possible under this category but are isolated in nature. Damaging winds and large hail become scattered in this category with tornadoes still low in coverage . In some instances, damaging winds may eclipse 70 mph, and hail could be up to golf ball sized. In our area, these risks are commonly issued a couple times a month during severe weather season.

3- Enhanced Risk: Numerous severe thunderstorms possible.

An enhanced risk for severe weather means numerous severe storms are possible and are more persistent and widespread with a few instances of very intense storms. Under this risk, several spots will likely experience damaging winds and/or large hail. More significant winds and hail become a little more common. In these instances, a few tornadoes can be possible, possibly on the strong side. In our area, this risk is not that common and usually are issued on average once a year. Eastern portions of Virginia will see this risk a few times a year.

4 - Moderate Risk: Widespread severe thunderstorms likely.

A moderate risk for severe weather is significant. Widespread severe weather is likely. Storms can be long-lived and intense. This is when there is a greater chance to see damaging winds and large hail than not in a 25-mile radius. Intense supercells are likely or significant straight-line winds in storms develop. Tornado outbreaks can happen in this category. Moderate risks are only issued a handful of times a year for the entire country, and are rarely issued anywhere in Virginia.

5 - High Risk: Widespread severe thunderstorms expected.

A high risk for severe weather means widespread severe storms are expected. Storms can be very long-lived, widespread, and powerful. This is when you typically see major tornado outbreaks or derechos. High risks for severe weather are issued on a rare occasion. The last time our viewing area saw severe weather at this magnitude was when the 2012 derecho tore through the area.

While, of course, you don’t need to memorize these categories, it is important to stay weather aware as these convective outlooks are designed to give you a heads-up on areas of potential severe weather days in advance.

Ahead of incoming severe weather, make sure your weather radio is on, has fresh batteries, and the volume is up. Secure any loose or light outdoor items.

First Alert Weather Day preps
First Alert Weather Day preps(WMC)

And, be sure to download the WMC Action News 5 First Alert Weather app. You’ll have instant access to any watches or warnings that may be issued, live interactive radar, hour-by-hour forecast and special video updates from the First Alert Weather Team.

How to download the WMC First Alert Weather app
How to download the WMC First Alert Weather app

Also, be sure to follow WMC Action News 5 and the First Alert Weather Team on social media for additional updates:

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