Showalter Index Calculator

Tropical Depression in the Gulf; Severe Thunderstorms Monday

Tropical Depression Two is expected to gradually strengthen and could bring tropical storm conditions to the Florida Panhandle beginning late Monday. Areas of flash flooding will be possible through Thursday along the eastern and central Gulf Coast. Severe thunderstorms will develop and move along a cold front crossing the Upper Midwest Monday, and through the Ohio Valley/Mid-Atlantic on 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 Depression in the Gulf; Severe Thunderstorms Monday

Showalter Index

by Tim Brice and Todd Hall

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