Knowledge Base

March 2nd, 2025 -- 2 weeks before this significant tornado outbreak: StormNet forecasts are outputting extremely rare >20% tornado probabilities for parts of the deep south and southeast. 

For reference, the gold standard for severe weather prediction, the Storm Prediction Center (SPC), produces tornado forecasts only up to 2 days out, and severe storm forecasts to 8 days into the future. 

Based on our climatological analysis, probabilities only exceed these levels at this lead-time a few times per year. 

10 days out and StormNet's forecasts are still very high relative to climatology. Tornado probabilities now exceed 50% for parts of the deep south, an occurrence we see very rarely in our annual recurrence analysis. 

Annually, we'd expect to see probabilities this high less than 5 times per year at 240 hours of lead-time. 

Since this is 10 days out, there are still no SPC forecasts valid from this period. The local forecast discussions from the National Weather Service make no mention of possible severe weather in 10 days.

March 9th, 2025, one week before a deadly deep south tornado outbreak. The SPC, for the first time, outlines a risk area: they highlight a 15% 'Slight Risk' of severe thunderstorms for part of the deep south and southeast.

StormNet's 7 day forecast continues to hone in a similar part of the deep south, narrowing and refining with each forecast from 14 days out:

The SPC, at 5 days out, has now highlighted a 30% 'Enhanced' risk for severe thunderstorms across the deep south.

Their forecast describes "Portions of the Deep South into GA may see multiple rounds of severe convection with a mix of both supercell and QLCS storm modes potentially moving across the region, posing a concern for damaging tornadoes and swaths of severe winds."

The 5 day StormNet forecast continues to hone in on the specific region of south central Alabama and southern Mississippi. StormNet's tornado forecast was an exceptionally high 75%+, something we typically see around 0-2 times per year! These probabilities, at 5 days out, were only reached once in 2025. 

At 3 days before the outbreak, it was becoming clear that a destructive tornado outbreak would be likely. The SPC outlined a rare day 3 moderate risk of severe thunderstorms (no tornado-specific forecasts until 2 days prior). Stating in their forecast: "A severe weather outbreak is expected on Saturday from the central Gulf coast states/Deep South into the Ohio Valley. Significant tornadoes (focused across the South), swaths of damaging gusts, and hail are expected."

StormNet's tornado forecasts were similarly robust, with very high tornado probabilities focused on southern Mississippi into central Alabama. 

Probabilities this high, at this lead-time, only occurred once in 2025! This was a high confidence, high impact tornado outbreak. 

At 48 hours until the tornado outbreak onset, preparations were underway across the south for a destructive tornado outbreak. 

The SPC issued a moderate risk (level 4/5) for severe storms with a 15% chance of tornadoes in their day 2 outlook. They also issued a very rare day 2 high risk (level 5/5) for tornadoes in an amended day 2 outlook issued that afternoon. 

The 48-hour forecast from StormNet offered small adjustments from the previous days forecast, as StormNet was really honed in on the specific affected area for a few days (and several forecast cycles).