The TOR:CON Index
from Dr. Greg Forbes' Facebook Page

Severe Weather Expert, Dr. Greg Forbes developed the TOR:CON index to estimate the risk of a tornado on a given day or night near your area.

The TOR:CON index ranges from 0 to 10. Multiply the value by 10 to get your percentage chance of a tornado within 50 miles of a location. For example, a TOR:CON index of 6 means there's a 60% chance of a tornado within 50 miles of any location in the indicated area.

Note: By definition, a severe thunderstorm contains one or more of the following: hail at least 1 inch in diameter, wind gusts 58 mph or higher, or a tornado.

TOR:CON Value Descriptions

8+
Very high probability of a tornado
High probability of a tornado
Moderate chance of a tornado nearby, but hail and/or high wind gusts possible
Low chance of a tornado, but hail and/or high wind gusts possible
Near-zero chance of a tornado or a severe thunderstorm

Sunday Jun / 24th Last Updated: 06/21/18 4:00:36 PM

Isolated severe thunderstorms in east WY, east CO, southwest KS, northwest OK, north TX panhandle

TORCON- 2 to 3

A chance of severe thunderstorms in south MO, south IL, south IN, KY, TN, north and central AR, extreme north MS and AL

TORCON - 2 or less

A trough of low pressure gives a chance of severe thunderstorms from the TX and OK panhandles to the High Plains, with enough low-level shear for a tornado but high cloud bases that hold down the threat

The approach of an upper trough may help trigger storms despite an initial cap

Unstable air along and south of a stationary front may give pop-up-type severe thunderstorms from the Ohio Valley to Tennessee Valley

Monday Jun / 25th Last Updated: 06/21/18 4:00:10 PM

Isolated severe thunderstorms in extreme southeast CO, southwest, central and northeast KS, southeast NE, southwest IA, northwest OK, northeast TX panhandle

TORCON- 2 to 3 IA, NE, MO and northeast KS areas

2 rest of area

A chance of severe thunderstorms in southeast NC, central and east SC, east-central GA

TORCON -2 or less

A trough of surface low pressure from northeast KS to the TX panhandle and forcing from an upper low over NE give a severe threat, with wind shear most favorable for a tornado near Kansas City

A weak trough of low pressure may form in SC and give a severe threat

Tuesday Jun / 26th Last Updated: 06/21/18 3:59:40 PM

Scattered severe thunderstorms in southeast MN, central and south WI, north and central IL, central and northeast MO, east-central KS

TORCON- 3 WI and north IL areas

2-3 east-central KS and west-central MO

2 rest of area

A chance of a severe thunderstorm in southeast KS, north-central and southwest OK, northwest TX near Childress

TORCON - less than 2

A chance of a severe thunderstorm in east SC, southeast GA, southeast NC

TORCON- 1

An upper trough from MN to the KS/MO border and a surface low near the IA/MN border give a severe threat on their east and south flanks, with low-level shear adequate for a tornado in WI and north IL

A weak trough of low pressure may give a localized severe thunderstorm along the Southeast Coast

Saturday Jun / 23rd Last Updated: 06/21/18 4:00:54 PM

Isolated severe thunderstorms in southeast and east-central OK, north AR, south MO, north-central TX

TORCON- 2 to 3 OK area

2 rest of area

A chance of severe thunderstorms in east OH, PA, southwest NY, north WV, MD, NJ, DE, DE, north and east VA, east NC

TORCON - 2 or less

A surface low continues to slide east into OH, PA, and west NY while the upper low shears apart toward New England, probably making the severe threat less than on previous days

A surface low in central TX with a trough to south MO may focus a severe thunderstorm threat

Upper forcing is weak but low-level shear is enough for a stray tornado

Discuss Torcon on Facebook