The National Weather Service has issued a hazardous weather outlook for north and central Georgia, highlighting the potential for isolated thunderstorms, dangerously high heat index values, and an extended period of afternoon and evening storms throughout the upcoming week.

Bonus for the more weather-curious among you … To read an article about interpreting a weather news report with some of the typical terminology defined, follow this link.

What is in the statement?

The statement gives the following details:

This Hazardous Weather Outlook is for north and central Georgia.

.DAY ONE…Today and Tonight…

Isolated thunderstorms are expected this afternoon and evening. A
few storms may produce gusty winds, heavy rainfall, and frequent
lightning.

Heat index values will range from the upper 90s to just shy of
105 degrees across much of north and central Georgia this
afternoon and early evening.

.DAYS TWO THROUGH SEVEN…Monday through Saturday…

Scattered to numerous thunderstorms are expected Sunday through
Saturday, mainly in the afternoons and evenings. The potential for
organized or widespread severe weather is low, but a few storms
could produce localized damaging wind gusts, heavy rainfall, and
localized flash flooding each day.

Heat index values will range from 100 to 108 degrees across
portions of north and central Georgia on Monday and Tuesday.

What counties are affected?

The following counties are included in the hazardous weather outlook:

Baldwin, Banks, Barrow, Bartow, Bibb, Bleckley, Butts, Carroll, Catoosa, Chattahoochee, Chattooga, Cherokee, Clarke, Clayton, Cobb, Coweta, Crawford, Crisp, Dade, Dawson, DeKalb, Dodge, Dooly, Douglas, Emanuel, Fannin, Fayette, Floyd, Forsyth, Gilmer, Glascock, Gordon, Greene, Gwinnett, Hall, Hancock, Haralson, Harris, Heard, Henry, Houston, Jackson, Jasper, Jefferson, Johnson, Jones, Lamar, Laurens, Lumpkin, Macon, Madison, Marion, Meriwether, Monroe, Montgomery, Morgan, Murray, Muscogee, Newton, North Fulton, Oconee, Oglethorpe, Paulding, Peach, Pickens, Pike, Polk, Pulaski, Putnam, Rockdale, Schley, South Fulton, Spalding, Stewart, Sumter, Talbot, Taliaferro, Taylor, Telfair, Toombs, Towns, Treutlen, Troup, Twiggs, Union, Upson, Walker, Walton, Warren, Washington, Webster, Wheeler, White, Whitfield, Wilcox, Wilkes, Wilkinson

What is meant by “isolated” and “scattered”?

The NWS defines “isolated” as follows:

A National Weather Service convective precipitation descriptor for a 10 percent chance of measurable precipitation (0.01 inch). Isolated is used interchangeably with few.

“Scattered” has the following definition:

When used to describe precipitation (for example: “scattered showers”) – Area coverage of convective weather affecting 30 percent to 50 percent of a forecast zone(s).

Isolated thunderstorms and scattered thunderstorms are two terms used to describe different distributions of thunderstorm activity within a particular area. The main difference lies in the extent of coverage and how the thunderstorms are spatially distributed:

• Isolated Thunderstorms:
  • Relatively rare occurrences that happen sporadically and are generally confined to a limited area.
  • Characterized by being few and far between, with significant gaps between individual storm cells.
  • Typically cover less than 20% of the forecast area.
  • Can still be intense and may produce heavy rain, lightning, gusty winds, and possibly hail.
• Scattered Thunderstorms:
  • More widespread than isolated thunderstorms and cover a larger portion of the forecast area.
  • Numerous individual thunderstorms develop, but they are not continuous or widespread enough to be classified as a “line” or “cluster” of storms.
  • Generally cover between 30% to 50% of the forecast area.
  • Still leave considerable gaps between storm cells; not everyone will necessarily experience a thunderstorm.

In summary, isolated thunderstorms are fewer in number and more localized, while scattered thunderstorms are more widespread with numerous individual storms.

About the National Weather Service

The National Weather Service (NWS) is a part of the National Oceanic and Atmospheric Administration (NOAA). The NWS describes its role as follows:

“The National Weather Service (NWS) provides weather, water, and climate forecasts and warnings for the United States, its territories, adjacent waters and ocean areas, for the protection of life and property and the enhancement of the national economy.

These services include Forecasts and Observations, Warnings, Impact-based Decision Support Services, and Education in an effort to build a Weather-Ready Nation. The ultimate goal is to have a society that is prepared for and responds to weather, water and climate events.”