Tornado Threat Forecast: May 9-15, 2017

A slow-but-steady mid-May tornado threat appears to be in the works, mostly favoring the normal May targets of the central and southern Plains.

1-3 Day

Tuesday – Central and southern High Plains

NUMBER OF TORNADOES EXPECTED: 5-12 – CONFIDENCE: Normal
Tornado Hot-spot: None

Pros: Good directional shear, decent/good speed shear, low to moderate instability
Cons: Somewhat-weak upper-level support, questionable storm coverage in the southern High Plains, storm mode may go more linear in the central High Plains as storms mature.

Wednesday – Central and southern Plains, southwestern Midwest

NUMBER OF TORNADOES EXPECTED: 5-12 – CONFIDENCE: Normal
Tornado Hot-spot: Central and southern Plains

Pros: Low to moderate instability, decent/good low-level directional shear in the Plains, decent/good speed shear, decent upper-level supports in the Plains.
Cons: Weak directional shear in the southwestern Midwest, mostly unidirectional winds in the mid-to-upper levels.

Thursday – Southeastern Plains, southern Midwest

NUMBER OF TORNADOES EXPECTED: 2-5 – CONFIDENCE: Normal
Tornado Hot-spot: None

Pros: Low to moderate instability, decent/good speed shear, decent upper-level support.
Cons: Poor/decent directional shear, unidirectional or backing winds in the mid-to-upper levels.

4-7 Day

Friday – Southern Appalachians, North Carolina

NUMBER OF TORNADOES EXPECTED: 0-3 – CONFIDENCE: High
Tornado Hot-spot: None

Pros: Low to moderate instability, decent speed shear.
Cons: Mostly unidirectional winds, weak/decent upper-level support.

Saturday

No tornadoes expected.

Sunday – Central and southern High Plains

NUMBER OF TORNADOES EXPECTED: 0-3 – CONFIDENCE: Normal
Tornado Hot-spot: None

Pros: Low to moderate instability, decent/good directional shear.
Cons: Weak/decent speed shear, unidirectional/backing upper-level shear, questionable storm coverage.

Monday – Central and southern Plains

NUMBER OF TORNADOES EXPECTED: 4-10 – CONFIDENCE: Low
Tornado Hot-spot: None

Pros: Moderate instability, decent/good low-level directional shear, decent/good speed shear.
Cons: Weak upper-level dynamics, unidirectional mid-to-upper level winds, questionable storm coverage.