Storm Prediction Center Mesoscale Discussion 1330

   Mesoscale Discussion 1330
   NWS Storm Prediction Center Norman OK
   1108 AM CDT Tue Jun 17 2025

   Areas affected...the Front Range of CO and far southeast WY

   Concerning...Severe potential...Watch likely 

   Valid 171608Z - 171815Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Initially isolated storms along I-70 in east-central
   Colorado will pose a risk for severe hail. More widespread storms
   are expected to form along the Front Range by early afternoon with a
   primary threat of large to very large hail. A watch issuance is
   likely, with some uncertainty on timing.

   DISCUSSION...Convection has formed early atop the pervasive stratus
   deck across east-central/southeast CO, with more pronounced
   insolation in a confined wedge to its north across northeast CO.
   While the boundary layer is cool and still somewhat stable, a risk
   for severe hail may develop with this localized area of storms given
   sufficient deep-layer shear. 

   The pervasive stratus is indicative of the seasonably moist air mass
   banked against the southern Rockies. Forecast soundings suggest only
   modest boundary-layer heating is needed for uncapped parcels, with
   most 12Z guidance indicative of scattered to widespread storms along
   the Front Range by early afternoon. With weak low-level shear,
   overall setup should be favorable for large to very large hail
   potential across the I-25 corridor. Very large hail appears more
   probable across the southern portion of the region where effective
   bulk shear should be maximized across the COS/PUB vicinity.

   ..Grams/Hart.. 06/17/2025

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

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

   LAT...LON   39430310 38730310 37550395 37760487 38340517 38870522
               39940524 40360532 40660536 41110529 41710484 41760447
               41670416 41030400 39430310 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN