Sep 22, 2018 0600 UTC Day 1 Convective Outlook
Updated: Sat Sep 22 05:05:35 UTC 2018 (20180922 1200Z Day 1 shapefile | 20180922 1200Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20180922 1200 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Tornado Graphic
20180922 1200 UTC Day 1 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 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20180922 1200 UTC Day 1 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 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Large Hail Graphic
20180922 1200 UTC Day 1 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 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
   SPC AC 220505

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1205 AM CDT Sat Sep 22 2018

   Valid 221200Z - 231200Z

   ...NO SEVERE THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   The risk for severe thunderstorms appears negligible across the U.S.
   today through tonight.

   ...Discussion...
   A deep surface cyclone and associated vigorous short wave trough
   appear likely to progress east of Newfoundland and Labrador into the
   northwestern Atlantic during this period.  In their wake, broad
   troughing within the mid-latitude westerlies is forecast to linger
   across southeastern Canada, the Great Lakes and Northeast. 
   Upstream, models indicate that troughing will progress inland across
   the Pacific Northwest coast.  To the south of the mid-latitude
   westerlies, much of the southeastern U.S., and the northern Mexican
   Plateau and adjacent portions of the Southwest, may remain under the
   influence of modest subtropical ridging.  To the north of the ridge
   axis, one perturbation is expected to slowly continue shifting from
   the southern Plains into the lower Mississippi Valley, while a wave
   in the easterlies migrates from just west of the Florida peninsula
   toward the north central Gulf of Mexico.
     
   In lower levels, a cold front trailing from the cyclone appears
   likely to stall and begin to weaken across the southern Mid Atlantic
   Coast, southern Appalachians, Tennessee Valley and Ozark Plateau. 
   However, it is forecast to maintain a southeastward progression from
   the southern Plains into the Sabine Valley and Texas Gulf coast. 
   Seasonably high moisture content will remain confined to areas along
   and southeast of the front, with the front providing the primary
   general focus for thunderstorm development today through tonight. 
   With this mostly south of the stronger westerlies, in an environment
   characterized by relatively warm mid-levels and modest to weak
   lower/mid tropospheric lapse rates, the risk for storms capable of
   producing severe wind and/or hail still appears negligible at this
   time.

   ..Kerr/Squitieri.. 09/22/2018

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z