Showalter Index Calculator

Nor'Easter Continues to Bring Heavy Rain and Coastal Impacts; Nolo Continues to Impact Hawaii

The nor’easter will weaken tonight, easing beach conditions and coastal flooding, though locally heavy rain will continue in parts of the Mid-Atlantic and New England into Monday. Hurricane Nolo continues to bring strong winds and large waves to Hawaii. A multi-day rain event will return to the Four Corners region Monday and expand to the south-central U.S. by midweek. 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.

Nor'Easter Continues to Bring Heavy Rain and Coastal Impacts; Nolo Continues to Impact Hawaii

Showalter Index

by Tim Brice and Todd Hall

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