Dangerous Heat in the Central and Eastern U.S.; Severe Thunderstorms in the Central U.S. and Northeast; Critical Fire Weather in the Four Corners

Dangerous, record-breaking heat will intensify across most of the central and eastern U.S this week. Heat indices will likely exceed 100 degrees. Severe thunderstorms are forecast from parts of the central High Plains into the Upper Midwest, and across parts of the Northeast. Critical fire weather conditions will continue across portions of the Four Corners and Great Basin. 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

Dangerous Heat in the Central and Eastern U.S.; Severe Thunderstorms in the Central U.S. and Northeast; Critical Fire Weather in the Four Corners

Convective Parameters - EHI