Mesoscale Discussion 0434
   NWS Storm Prediction Center Norman OK
   1215 PM CDT Tue Apr 27 2021

   Areas affected...portions of northeastern Colorado

   Concerning...Severe potential...Watch likely 

   Valid 271715Z - 271945Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Convective initiation is underway across portions of
   northeast Colorado. The threat for severe hail is expected to
   gradually increase through the afternoon and a Severe Thunderstorm
   Watch issuance is likely.

   DISCUSSION...Overcast skies are overspreading a post-cold frontal
   airmass across northeast Colorado, with surface temperatures varying
   in the lower 50s to near 60F, and with 40-50F dewpoints noted.
   Nonetheless, RAP forecast soundings suggest 100 mb deep rich
   low-level moisture is in place, and is being overspread by 8+ C/km
   mid-level lapse rates (evident via the 12Z DNR observed sounding).
   With continued diurnal heating and the approach of an embedded
   mid-level vort-max in New Mexico, an uptick in convective coverage
   and intensity is expected. Increasing mid-level wind speeds are
   fostering 50+ kts of effective bulk shear, suggesting that any
   storms that can mature may remain organized long enough to support
   the production of large hail. With modest low-level lapse rates in
   place, a couple damaging gusts also cannot be completely ruled out.
   As such, a Severe Thunderstorm Watch issuance is anticipated.

   ..Squitieri/Hart.. 04/27/2021

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...GLD...PUB...BOU...

   LAT...LON   38650418 38830453 39270469 39850482 40470499 40820490
               40910457 40980399 40940297 40680240 40200207 39710203
               39330215 39080231 38790269 38590304 38500363 38650418