Storm Prediction Center convective outlook changes

The Storm Prediction Center (SPC) day 1-3 convective outlooks have gotten a new look, effective October 22, 2014 at 1500 UTC (11 a.m. eastern). It is all in an effort to communicate the risks more effectively for severe weather events.

Here’s a preview…. NO MORE “SEE TEXT”!! (Now if we could just get rid of “slight.”)

They are expanding the current day 1-3 format from four to five categories.

SPC old Day 1-3 convective outlook. Courtesy: SPC/NOAA
SPC old Day 1-3 convective outlook. Courtesy: SPC/NOAA

Here is what the new outlook will look like for the same scenario.

SPC newDay 1-3 convective outlook. Courtesy: SPC/NOAA
SPC newDay 1-3 convective outlook. Courtesy: SPC/NOAA

As you can tell… it adds another layer to show where SPC meteorologists forecast where the biggest impacts will be located.

Categories (from SPC):

Old:

1. See Text
2. Slight (SLGT)
3. Moderate (MDT)
4. High (HIGH)

New:

1. Marginal (MRGL) – replaces the current SEE TEXT and now is described with Categorical line on the SPC Outlook.
2. Slight (SLGT)
3. Enhanced (ENH) – will replace upper-end SLGT risk probabilities, but is not a MDT risk
4. Moderate (MDT)
5. High (HIGH)

Here is what the April 27, 2011 severe weather outbreak would have looked like with the new categories.

April 27, 2011 severe weather outbreak with new categories. Courtesy: SPC/NOAA
April 27, 2011 severe weather outbreak with new categories. Courtesy: SPC/NOAA

As you can see… it will help define the greatest risk of severe weather more clearly. However, it’s only good if users (you/the public) know what it means…

It will be up to meteorologists at The National Weather Service, broadcasters, Emergency Managers, Social Media, etc. to communicate the risk in each specific area accurately and effectively.

There are a lot more details about the technical aspects of how each category is assigned (thresholds, etc). You can read more info directly from SPC, and I suggest you do so, by going here.

Current Day One Convective Outlook: 

Current SPC Day One Convective Outlook

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