Sep 27, 2023 1730 UTC Day 2 Convective Outlook
Updated: Wed Sep 27 17:29:54 UTC 2023 (20230927 1730Z Day 2 shapefile | 20230927 1730Z Day 2 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20230927 1730 UTC Day 2 Outlook Graphic
Day 2 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Tornado Graphic
20230927 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
20230927 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
No Risk Areas Forecast
Probabilistic Large Hail Graphic
20230927 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 271729

   Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1229 PM CDT Wed Sep 27 2023

   Valid 281200Z - 291200Z

   ...NO SEVERE THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   Severe thunderstorms appear unlikely on Thursday.

   ...Synopsis...
   Broad upper troughing is forecast to persist from the Pacific
   Northwest/Great Basin into the northern High Plains on Thursday,
   supported by a series of shortwave troughs moving through it base.
   Lead wave in this series will begin the period extended from
   southern Saskatchewan through central MT, before then progressing
   quickly eastward. Surface low will take a similar track to this
   shortwave, with an attendant cold front pushing eastward across the
   Dakotas. Low-level moisture will be limited ahead of this front,
   keeping thunderstorm chances low. Another shortwave trough is
   forecast to move into the northern/central High Plains late Thursday
   night/early Friday morning, resulting in a dynamically enhanced
   low-level jet from the southern High Plains through the central
   Plains. Isentropic ascent across the frontal zone will support
   isolated thunderstorms. Vertical shear and buoyancy will remain
   modest, limiting the overall severe potential.

   Westerly flow aloft is expected to persist south of the primary
   troughing as well, helping to support continued lee troughing across
   the High Plains. Strong boundary-layer mixing is anticipated east of
   the lee troughing, with the highest likelihood for isolated
   thunderstorm development across the southern High Plains.

   Across the eastern CONUS, a weakening upper low will likely begin
   the period over southern Lower MI before gradually drifting
   northeastward into southwestern Ontario. An associated surface low
   is forecast to drift eastward across the OH Valley. A weak boundary
   will extend southwestward/westward from this low, with showers and
   thunderstorms reinforcing this boundary throughout the morning. Weak
   convergence is possible along this boundary during the afternoon,
   with some chance for afternoon/evening thunderstorm development from
   central KY into southwest MO and western/middle TN. Modest buoyancy
   and weak shear should limit the overall severe threat.

   ..Mosier.. 09/27/2023

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