Showalter Index Calculator

Fire Weather Conditions Persist in the Southern Plains; Heavy Rain and Mountain Snow in the Pacific Northwest

A Pacific system will continue to bring moderate to heavy low elevation rain from northern California to western Washington, and heavy snow to the Cascades and Intermountain West over the next several days. Elevated to critical fire weather conditions will persist across the southern Rockies and Southern Plains through Wednesday as gusty winds and dry conditions continue across the region. Read More >

Showalter Index

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What does my answer mean?

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.

Fire Weather Conditions Persist in the Southern Plains; Heavy Rain and Mountain Snow in the Pacific Northwest

Showalter Index

by Tim Brice and Todd Hall

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