With a deep longwave trough shifting to the northwest this week, some disturbances (short waves) in the flow will allow a forced upward move (causing divergence) during the week’s severe weather conditions. this throughout the Great Plains. We can see that downstream of this trench we will also have warm air moving forward by mean southerly flow, so we know for sure there will be a lot of lift. On the surface we will see a low pressure forming over the Front Strip and with it pulling a dry line eastward, along and east of it which we will need to monitor! The question becomes, what about the extreme weather settings and parameters now?
We are looking at deep laminar shears (0-4km) of more than 25-30 knots, which determine the type of storm because it organizes convection and can allow alternating currents if we have enough CAPE.
As we see verbatim, the modeled CAPE will be more than enough with over 800 j/kg across the Delta, but more importantly over 1000 j/kg targeted from KS to OK and into TX.
At 850mb we see a low-level ray that pre-reacts to the developing surface low pressure and downstream of the trough, which happens to coincide nicely with the CAPE parameter space above due to humidity cause instability by providing rapid drift (increasing surface temperature), which will also play a role on Friday in relation to severe weather. In terms of humidity, the 2m dew points will increase in the 60s all the way south of NE, which is more than enough and sees a clear demarcation between low and high dew points that outlines the dry line from TX to KS.
When we put the components together, we’re looking at all serious hazards (lower tornado rates), with heavy hail possibly due to a generally favorable atmospheric setup. and we can see some sporadic convection forming ahead of the dry line tomorrow afternoon and evening across KS, east of OK, and near/around Dallas to the north. This also coincides with the SPC’s outlook revealing where they consider the greatest risk for strong to severe thunderstorms because they have the area mapped out as “slightly”.
Most of the possible hazards on setup would be heavy hail and gusty winds, especially with anything that becomes sporadic and crosses all limits in the afternoon. As of now, the convection looks likely to start in KS and then OK in the late afternoon. A bit more uncertainty exists north of TX as it seems more dependent on what shortwaves can do later in the afternoon/evening and along the dry line, but if anything is possible then we can also consider severe cells with inexcusable large hail and microbursts. This threat will move into tomorrow and will spread throughout the MS River Valley as Meghan will have a blog on those details tomorrow. Keep stable!
About the author
Hello! My name is Armando Salvadore and I am a Mississippi State graduate with a Bachelor of Professional Meteorology and an Activity Meteorologist working in the Private Sector. Stay tuned if you like technical, exotic, and general weather tweets! Also big on long-range forecasting as well! Twitter: @KaptMands