Showalter Index Calculator

Fire Weather Concerns in the Intermountain West into the Plains

Anomalously warm, dry and breezy conditions will bring elevated to critical fire weather conditions across portions of the Intermountain West into the Plains though early this week. Another elevated risk is possible across the central Appalachians. A rapid warm-up is in the forecast beginning Monday across the central and eastern U.S.. 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.

Fire Weather Concerns in the Intermountain West into the Plains

Showalter Index

by Tim Brice and Todd Hall

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