- Joined
- Dec 10, 2023
Alright, here's the promised model breakdown and forecast.



There is currently an Enhanced (level 3/5) risk for parts of Illinois, Indiana and Missouri, with a Slight (level 2/5) risk extending southward into Kansas, Oklahoma, Arkansas and Texas. The main threat is several tornadoes (some strong) and hail in Illinois and parts of Missouri, as well as a lesser threat of the two localized around west Texas.
Personally, I'd be surprised if the Enhanced risk wasn't upgraded to a Moderate risk, considering the environment being forecasted (which I will get into now, focusing on Illinois and the surrounding area)


In Illinois and parts of Missouri and Indiana, an unusually volatile environment for March standards is being depicted by models, with surface CAPE values (which represent instability in the atmosphere) in the 3,000 to 4,000 J/kg range, which is extremely high for March, which usually sits around 1,500 to 2,000 J/kg in a higher-end severe weather setup around this time. Combined with strong wind shear (spin in the atmosphere) indicated by effective SRH values around 300 m²/s², any organized storm will have sufficient atmospheric conditions to produce a tornado, and any supercell that remains discrete enough will have the chance to produce a strong tornado, and a violent (EF4+) tornado cannot be ruled out in my opinion.


Regarding the formation of storms, there is very little capping for storms (indicated by surface-based CIN) and ample lift in the atmosphere (indicated by surface-based LI), meaning that any storm that does initiate should not have difficulty organizing itself. The only question in regards to this is the coverage of storms, the storm mode (whether it's individual supercells or a cluster of storms) and at what time they will initiate. Current models show that storm coverage is limited and convective initiation may occur only after 0000 UTC, but it's entirely possible that won't be the case, since CAMs are pretty inconsistent until the day of the event.
Once the new Day 2 outlook comes out, and models start to paint a clearer picture of what may occur, I will (probably) give another update.



There is currently an Enhanced (level 3/5) risk for parts of Illinois, Indiana and Missouri, with a Slight (level 2/5) risk extending southward into Kansas, Oklahoma, Arkansas and Texas. The main threat is several tornadoes (some strong) and hail in Illinois and parts of Missouri, as well as a lesser threat of the two localized around west Texas.
Personally, I'd be surprised if the Enhanced risk wasn't upgraded to a Moderate risk, considering the environment being forecasted (which I will get into now, focusing on Illinois and the surrounding area)


In Illinois and parts of Missouri and Indiana, an unusually volatile environment for March standards is being depicted by models, with surface CAPE values (which represent instability in the atmosphere) in the 3,000 to 4,000 J/kg range, which is extremely high for March, which usually sits around 1,500 to 2,000 J/kg in a higher-end severe weather setup around this time. Combined with strong wind shear (spin in the atmosphere) indicated by effective SRH values around 300 m²/s², any organized storm will have sufficient atmospheric conditions to produce a tornado, and any supercell that remains discrete enough will have the chance to produce a strong tornado, and a violent (EF4+) tornado cannot be ruled out in my opinion.


Regarding the formation of storms, there is very little capping for storms (indicated by surface-based CIN) and ample lift in the atmosphere (indicated by surface-based LI), meaning that any storm that does initiate should not have difficulty organizing itself. The only question in regards to this is the coverage of storms, the storm mode (whether it's individual supercells or a cluster of storms) and at what time they will initiate. Current models show that storm coverage is limited and convective initiation may occur only after 0000 UTC, but it's entirely possible that won't be the case, since CAMs are pretty inconsistent until the day of the event.
Once the new Day 2 outlook comes out, and models start to paint a clearer picture of what may occur, I will (probably) give another update.
