Showalter Index Calculator

Tropical Storm Bertha in the Gulf; Severe Weather in the East on Tuesday

Tropical Storm Bertha could bring tropical storm conditions to portions of the Florida Panhandle and Alabama coast through Wednesday, where a Tropical Storm Watch and Storm Surge Watch is in effect. Numerous severe thunderstorms with heavy rainfall are expected from the Ohio Valley into the Mid-Atlantic and Northeast Tuesday. Read More >

Showalter Index

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Showalter Index greater than 0: Stable, but weak convection possible for SI = 1-2 if strong lifting is present.
Showalter Index between 0 and -3: Moderately unstable.
Showalter Index between -4 and -6: Very Unstable.
Showalter Index between less than -6: Extremely Unstable.

Tropical Storm Bertha in the Gulf; Severe Weather in the East on Tuesday

Showalter Index

by Tim Brice and Todd Hall

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