NOAA Storm Prediction Center

Convective Outlooks

Convective Outlooks
The convective outlooks serve as guidance to the local NWS forecast offices and are used by emergency managers, private sector meteorologists, media, and other weather customers concerned with public safety. Three separate risk areas (slight, moderate, and high) are used to describe the expected coverage and intensity for the categorical severe weather threat on days 1-3 along with severe weather probabilities for the potential threat.

Day 1 Outlook Day 2 Outlook Day 3 Outlook Days 4-8 Outlook

Day 1 Outlook Convective Tornado
Hail Wind
Categorical Day1 1300Z Outlook
Images courtesy of the NWS Storm Prediction Center
 Forecast Discussion

ACUS01 KWNS 221224
SPC AC 221222

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0722 AM CDT Thu Apr 22 2021

Valid 221300Z - 231200Z


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

Two areas of more confident thunder potential are apparent, mainly
this afternoon into early evening. First, a shortwave impulse moving
southeast from British Columbia in conjunction with a steep low to
mid-level lapse rate environment will be supportive of isolated
thunderstorms across the northern Intermountain West. The other is
downstream of a positive-tilt upper trough over the Southwest.
Isolated thunderstorms are possible from northern AZ to CO. 

Less confident thunder potential is apparent over the southern
Sierra NV mountains and KS to the southern Great Plains. For the
latter region, a stout EML should largely inhibit thunderstorm
development until the D2 period. Highly elevated parcels with scant
buoyancy might support low-probability thunder along the edge of
this stout EML across the southern KS vicinity towards the end of
the period.

..Grams.. 04/22/2021