An Enhanced Risk of severe thunderstorms exists today from southeastern Oklahoma to southern Missouri. Tornadoes, large to very large hail, and strong to locally severe wind gusts are possible.

Location

  • Southeastern Oklahoma
  • Arkansas
  • Southern Missouri
  • Potentially extending into portions of:
    • Northeastern Texas
    • Eastern Oklahoma
    • Mississippi Valley
    • Tennessee Valley
    • Ohio Valley

Threats

  • Tornadoes
  • Large to very large hail
  • Strong to locally severe wind gusts

Timing

  • This afternoon into the evening

Discussion

  • Storm Drivers
    • A cutoff upper-level low over the Southwest U.S. and a separate shortwave impulse over the Central Great Plains will interact to create favorable conditions for storms.
    • Strong heating near a slow-moving boundary (either dryline or cold front) will increase instability, fueling storm development.
    • Wind shear increases through the day, with small hodographs initially as storms fire.
  • Storm Evolution
    • Isolated supercells are likely initially, capable of producing all severe hazards, including very large hail.
    • Storms may form before the noon hour today.
    • Storms are expected to become more widespread in the late afternoon/early evening, forming into clusters.
    • While the tornado risk may increase initially, the overall severe threat will likely trend downward overnight, with embedded supercells and localized bows posing sporadic risks.

Uncertainties

  • Ohio Valley: Pre-existing storms this morning could affect how severe the afternoon storms become in areas like Indiana and Ohio. This introduces uncertainty into the forecast for that region.
Storms look to begin before noon with large hail the initial threat.
As the afternoon wears on, a risk of giant hail and tornadoes will increase. Storms will also become more widespread and numerous.
Towards evening, a mixed mode of storms will exist. This will include bow echos with damaging straight line winds and supercells with giant hail. Tornadoes will also be possible.
Initial hodographs will be small today, but any dominant supercell would have a chance to produce tornadoes at the outset of the event.
Shear increases through the afternoon, but weak low-level flow even into the last afternoon may keep the tornado risk at low. Still, given the amount of storms it is likely a couple produce tornadoes across Eastern Oklahoma.
The tornado risk will likely peak in the hours around sunset, especially with any mature supercells that can maintain clean inflow across Arkansas.