Atmospheric River Continues to Impact the Northwest U.S.; Gusty to High Winds in the Northeast U.S.

A strong atmospheric river will continue moderate to heavy rainfall with possible flooding, gusty to high winds, and mountain snows for parts of the Northwest U.S. into Thursday. Additional impacts are likely into Friday with a cold front. A fast-moving storm system will cross the Northeast U.S. Wednesday into Thursday with gusty to high winds and areas of rain and high elevation snow showers. Read More >

Automatically generated image showing areas of energy helicity index.


Hour - 1	Hour - 2	Hour -3

4 Panel Display | Animated Loop

EHI

The Energy Helicity Index (EHI) is a number which represents the combination of instability and storm relative helicity. Our calculation uses mixed layer CAPE (surface to 3000ft average parcel) and 0-3 km storm relative helicity. Values greater than 2 or 3 have been correlated to cyclonic supercells with increased tornadic potential. Negative values are indicative of an environment favorable for anti-cyclonic (left moving) supercells, but tornadoes associated with anti-cyclonic supercells are extremely rare.

Back to Convective Parameters Home

FWD RSS Feed

Atmospheric River Continues to Impact the Northwest U.S.; Gusty to High Winds in the Northeast U.S.

Convective Parameters - EHI