Showalter Index Calculator

Tropical Storm Milton Strengthening in the Gulf of Mexico; Dangerous Heat in the Southwest

A late season heat wave will continue across portions of California into the Desert Southwest. Meanwhile, Tropical Storm Milton is strengthening in the southwest Gulf of Mexico. Milton is expected to become a major hurricane and bring significant impacts to Florida this upcoming week. 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 Milton Strengthening in the Gulf of Mexico; Dangerous Heat in the Southwest

Showalter Index

by Tim Brice and Todd Hall

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