ZSE TCF

Dangerous Heat Continues Across the South; Severe Thunderstorms Possible From Central/Southern Plains to Ohio Valley

Heat Advisories and Excessive Heat Warnings are in effect through this weekend across the Southern U.S. Isolated severe thunderstorms with damaging winds and hail will be possible Sunday across portions of the southern U.S. into the Ohio Valley and central Appalachians, as well as across parts of the central and southern High Plains. Read More >

Traffic Flow Management Convective Forecast (TCF)

TCF Legend

TCF +4hr Forecast

TCF +6hr Forecast

TCF +8hr Forecast

Product Description:

The TCF is a high confidence graphical representation of forecasted convection meeting specific criteria of coverage, intensity, and echo top height. The TCF graphics are produced every 2 hours and valid at 4-, 6-, and 8-hours after issuance time.

Areas of convection in the TCF include any area of convective cells containing (at a minimum):

Composite radar reflectivity of at least 40 dBZ;

Echo tops at or above FL250;

Coverage (a and b) of at least 25% of the polygon area;

Forecaster confidence of at least 50% (High) that criteria (a, b, and c) will be met.

Lines of convection in the TCF include any lines of convective cells:

Composite radar reflectivity of at least 40 dBZ having a length of at least 100 nautical miles (NM); and

Having a linear coverage of 40% or greater; and

Having echo tops at or above FL250.

Forecaster confidence of at least 50% (High) that criteria (a, b, and c) will be met.

All four of the threshold criteria listed above for both areas and lines of convection are required for inclusion in the TCF. This is defined as the minimum TCF criteria.

The TCF domain is the Flight Information Regions (FIR) covering the 48 contiguous states and adjacent coastal waters. It also includes the Canadian airspace south of a line from Thunder Bay, Ontario to Quebec City, Quebec.