Severe Weather Risk Overnight

Forecast Discussion

…risk of strong and/or severe thunderstorms across central and south central Texas late tonight into early Wednesday morning…

…strongest storms will be capable of producing large hail, strong gusty winds, torrential downpours, and dangerous cloud to ground lightning…

…an isolated tornado cannot be ruled out, but does not appear to be likely at this time…

…overall, 0.50-1.50 inches of rain can be expected across the area…flooding threat appears to be low at this time given the progressive (fast-moving) nature of this storm system…

Severe Weather Threat

The Storm Prediction Center (SPC) has placed areas along and west of the I-35 corridor (including the Austin Metro Area) under a SLIGHT RISK for severe weather late this evening and overnight...MARGINAL RISK for areas south and east of Austin.

The greatest threat for severe weather and tornadoes will be across west Texas and especially northwest Texas from Abilene to Wichita Falls to Childress where they are under a MODERATE RISK for severe weather (red shaded region).

Understanding Severe Risk Categories 

…the slight risk outlook is considered a threat level 2 in the 5 threat severe weather outlook system.

1.      Marginal

2.      Slight

3.      Enhanced

4.      Moderate

5.      High

(See chart below for a more detailed understanding of each threat level)

Detailed Forecast Explanation

A potent upper level low pressure system and its attendant cold front will move from west to east across the area during the overnight hours tonight lifting the warm, muggy, and unstable air mass currently in place across the area. The lift associated with this low pressure system at the mid and upper levels of the atmosphere will work together with surface lift provided by an eastward moving cold front to produce a line of thunderstorms across west Texas that will march east towards central Texas late tonight/early Wednesday morning. Some of the embedded storms within this line of storms are expected to be severe as they move across the area late tonight (especially across the Hill Country).

Storm Timeline

10pm to Midnight | Storms approach the western Hill Country

Midnight to 2am | Storms moving through the Hill Country…approaching Travis, Hays, and Williamson Counties

2am to 5am | Storms moving through the I-35 corridor and counties just east of the I-35 corridor

5am to 7am | Storms moving through eastern areas of central Texas
After 7am | Storms exiting the area to the east as drier and more stable air infiltrates the region from the west…clearing skies expected midday Wednesday

Forecast Radar (2 a.m. Wednesday morning)