Tornado Outbreak Likely: 5/16
NAM simulated radar forecast for
5 p.m. CDT
Convection this morning across the Texas panhandle into portions of Oklahoma and Kansas is ongoing and while this may have a small impact on the scope and severity of the impending event today, much of it should tend to weaken through early afternoon. A small portion of the storms may re-intensify, particularly across northwestern Oklahoma, early in the afternoon. While these storms may become severe and pose a marginal tornado risk, there is a heightened risk of tornadoes, some strong, by mid to late afternoon.
Computer model guidance aside, surface observations at 10 a.m. indicated varying amounts of cloud-cover over the Texas panhandle, to northwest Texas and much of western and central Oklahoma. Dew-points in the warm sector were largely in the mid-60s. Locally backed winds and residual outflow from the morning convection will likely locally enhance the tornado threat later on. With some clearing, pockets of moderate to strong instability should develop this afternoon and combine with strong winds aloft and impressive wind shear to produce an environment that one would expect in a tornado outbreak. Now, this is not a flawless tornado outbreak setup. Ongoing convection will influence and perhaps mitigate the threat a bit and there is also a concern of backing winds aloft (winds in the mid to upper levels a bit more southerly than westerly, or in other terms, veer-back-veer). These factors do not erase the tornado threat, but can limit it somewhat.
With all of that said, here is what I expect:
A few storms may locally become severe with a tornado or two across northwestern Oklahoma and possibly into south-central Kansas between noon and 2 p.m. At the same time, or shortly thereafter 1 to 3 p.m., convective initiation is likely along and just ahead of a dryline across the Texas/Oklahoma panhandles into southwestern Kansas. These storms should move into an increasingly unstable environment and rapidly become severe with numerous tornadoes. The storm mode north of the Oklahoma/Kansas border is a bit questionable, as it may be more messy there. Further south, there is a greater threat of discrete, intense supercells developing with tornadoes. The initial line of storms will then shift eastward through Oklahoma and Kansas, with the dryline storms moving into western Oklahoma, northwestern Texas and west-central Kansas by mid to late afternoon.
For the tornado threat, I think it will be maximized near the western panhandle of Texas into adjacent Oklahoma. Here, I would imagine at least one or two strong tornadoes will be reported. Locations in this general area include Childress, TX and Elk City, OK. As the storms continue eastward, there will probably be some storm mergers and an increasingly messy storm mode, but a few discrete supercells can persist toward the I-44 to I-35 corridor in central Oklahoma. Places like Wichita Falls and Oklahoma City may be on the eastern fringe of the greatest tornado threat. While this means tornadoes, possibly strong, are still possible there, the threat appears higher further west. The target time for that I-44 to I-35 corridor looks to be late afternoon, mainly after 5 p.m. and into the early evening hours.
There is less certainty on the tornado threat northward into Kansas and points north. Here, less instability is forecast and ongoing storms are another issue. With that said, I would still expect multiple tornadoes in Kansas, with the possibility of a tornado becoming strong, if it can stay isolated from other convection. A broader tornado threat also extends further north of Kansas, but there the threat is much less significant.
While it is great to look at computer forecast models to get an idea for what may happen, it is crucial to understand what is happening meteorologically. That goes for surface observations, radar and satellite imagery, as well as conditions in the mid and upper levels. Trends will be monitored through the day to see what happens.
