Oct 21, 2021 1730 UTC Day 2 Convective Outlook
Updated: Thu Oct 21 17:18:33 UTC 2021 (20211021 1730Z Day 2 shapefile | 20211021 1730Z Day 2 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20211021 1730 UTC Day 2 Outlook Graphic
Day 2 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 17,026 1,428,843 Greenville, NC...Jacksonville, NC...Rocky Mount, NC...Wilson, NC...Goldsboro, NC...
Probabilistic Tornado Graphic
20211021 1730 UTC Day 2 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Day 2 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20211021 1730 UTC Day 2 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Day 2 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 17,094 1,449,277 Greenville, NC...Jacksonville, NC...Rocky Mount, NC...Wilson, NC...Goldsboro, NC...
Probabilistic Large Hail Graphic
20211021 1730 UTC Day 2 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Day 2 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
   SPC AC 211718

   Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1218 PM CDT Thu Oct 21 2021

   Valid 221200Z - 231200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN
   NORTH CAROLINA...

   ...SUMMARY...
   A few storms might produce locally strong to damaging wind gusts
   over a portion of eastern North Carolina during the afternoon. Some
   risk for marginally severe hail will exist late Friday night with
   any storms developing across northeast Oklahoma and southern Kansas.

   ...NC...

   Weak short-wave trough currently located over the central High
   Plains is forecast to dig southeast into the TN Valley by the start
   of the day2 period. This feature will then eject into the middle
   Atlantic as a speed max translates across the southern Appalachians
   into southeast VA during the afternoon. Resultant surface pressure
   rises across the TN/OH Valley region will force a cold front east of
   the higher terrain to a position from southeast VA-central Carolinas
   after 18z. This boundary will serve to focus convection, especially
   as boundary-layer heating contributes to destabilization. Forecast
   wind profiles suggest some organization is possible, though
   low-level shear will remain somewhat weak. Have expanded low severe
   probabilities to include a bit more of eastern NC as forecast models
   suggest convection will easily develop ahead of this disturbance by
   peak heating. Locally damaging winds are the primary risk.

   ...OK/KS...

   Surface anticyclone will shift downstream into the TN Valley by the
   end of the day2 period. Lee cyclone will establish itself over the
   high Plains of southwest KS during the latter half of the period and
   this will encourage low-level moisture to advance north across TX
   into eastern KS as the LLJ strengthens across this region. While
   strong boundary-layer heating is expected across the High Plains,
   surface-based convection will likely struggle to initiate due to the
   expected presence of some CINH. However, elevated thunderstorms
   should develop during the overnight period within the warm advection
   zone over northeast OK/southeast KS. Forecast soundings suggest
   modest MUCAPE such that a few robust updrafts may be possible. At
   this time it appears marginally severe hail would be the primary
   risk.

   ..Darrow.. 10/21/2021

   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z