David Buckner Storm Chaser

WATCH LIKELY

Mesoscale Discussion 1089
NWS Storm Prediction Center Norman OK
1238 PM CDT Wed Jun 08 2022

Areas affected...The Ohio River Valley

Concerning...Severe potential...Tornado Watch likely

Valid 081738Z - 081945Z

Probability of Watch Issuance...80 percent

SUMMARY...The potential for severe weather, including a few
tornadoes, will increase in the coming hours for portions of the
Ohio River Valley. A watch will likely be needed to address this
potential.

DISCUSSION...Afternoon observations show a surface low gradually deepening as it translates east towards the OH River Valley region. Ahead of this low, a surface warm front is identified in both surface observations as well as GOES visible imagery in the form of a northward-advancing cumulus field. A diffuse, but discernible, cold front is also noted advancing eastward with the low. Although instability north of this boundary remains marginal, daytime heating (modulated to a degree by cloud cover) and northward advection of mid/upper 60s dewpoints have bolstered MLCAPE values to near 1000 J/kg. This instability is sufficient for deep convection (evidenced by a few ongoing thunderstorms along the front) despite some lingering inhibition. The northward advance of the warm front should allow favorable buoyancy to spread as far north as the lower half ofIN/OH by mid/late afternoon.

Aloft, a seasonally strong upper-jet is supporting 40-50 knots of effective bulk shear both along the warm front and across the warm sector to the south. Considerable veering in the lowest 2-3 km is noted in regional VWPs within the warm frontal zone with a nearly unidirectional flow field above this layer.

This hodograph structure will support the potential for supercells that may pose all hazards, especially along the surface warm front and near the surface low where low-level SRH will be maximized and storm residence time may be adequate to realize the favorable environment. Initially discrete storms appears likely with a gradual transition to clusters and/or a few line segments possible as storms interact along the boundary

Mesoscale Discussion 0851
NWS Storm Prediction Center Norman OK
1200 PM CDT Sat May 21 2022

Areas affected...Portions of far eastern IL into IN...western
OH...and far northern KY

Concerning...Severe potential...Severe Thunderstorm Watch likely

Valid 211700Z - 211900Z

Probability of Watch Issuance...80 percent

SUMMARY...Continuing to monitor a line of thunderstorms moving across Illinois for signs of increasing intensity and damaging wind potential. Watch issuance appears increasingly likely in the next couple of hours.

DISCUSSION...A cluster of thunderstorms is present over parts of southern/central IL at 17Z. This line has remained sub-severe so far, with wind gusts generally in the 35-45 kt range. Still, the airmass downstream into IN and northern KY continues to destabilize along and south of a front. MLCAPE of 1500-2500 J/kg has become common as temperatures warm into the 70s and 80s. Recent high-resolution guidance suggests that this ongoing cluster will intensify over the next couple of hours as it moves eastward across IN, northern KY, and eventually parts of western OH. Gradually strengthening southwesterly flow through mid levels is noted on recent VWPs from KVWX/KIND, which should aid in thunderstorm organization. Current expectations are for the cluster to pose a gradually increasing threat for scattered damaging winds as it encounters a more unstable airmass in IN and vicinity. Some hail may also occur with the strongest updrafts. Accordingly, Severe Thunderstorm Watch issuance appears likely in the next hour or two.

Dying storms slowly moving into Columbus OH May 14

A severe thunderstorm watch has been issued for portions of eastern Minnesota and northern/northwest Wisconsin until 5 PM CDT. A cluster of thunderstorms moving into the region this afternoon will be capable of damaging winds and large hail. For the latest warning information across the watch area go to:

www.weather.gov/mpx - Minneapolis, MN
www.weather.gov/dlh - Duluth, MN