SPC MD 1255
MD 1255 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR EAST-CENTRAL TO SOUTHEAST COLORADO



Mesoscale Discussion 1255
NWS Storm Prediction Center Norman OK
0140 PM CDT Mon Jun 22 2026

Areas affected...East-central to southeast Colorado

Concerning...Severe potential...Watch likely

Valid 221840Z - 222045Z

Probability of Watch Issuance...80 percent

SUMMARY...Thunderstorm development appears likely along the Front
Range from central to southern Colorado in the next 1-2 hours. Watch
issuance is likely as storms develop and spread east/southeast.

DISCUSSION...Latest GOES imagery depicts growing cumulus from the
Denver area southward along the Front Range and into the Raton Mesa
within a weak upslope flow regime. This comes as temperatures begin
to warm into the low to mid 80s, which latest CAM guidance suggests
is required to erode mixed-layer inhibition and support convective
initiation. Based on these satellite and temperature trends, deep
convective initiation appears probable within the next 1-2 hours.

Initially high-based convection will quickly spread east/southeast
given the 30-40 knot west/northwest flow regime aloft. Steady
intensification with eastward extent is expected as storms migrate
into the axis of rich low-level moisture (dewpoints in the upper 50s
to low 60s) in place along the eastern Plains. Additionally,
elongated hodographs featuring 40-50 knots of effective bulk shear
analyzed in recent mesoanalyses/forecast soundings (and confirmed by
regional VWPs) will promote splitting supercells capable of large to
very large hail (possibly as high as 2-3 inches) as well as strong
outflow winds. Watch issuance will be needed this afternoon as
initiation becomes more imminent and storms begin to mature.

..Moore/Hart.. 06/22/2026

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

ATTN...WFO...DDC...GLD...AMA...PUB...BOU...ABQ...

LAT...LON 36970280 37000336 37190395 37440450 37650481 37900503
38230522 38670542 39010540 39270522 39400488 39420443
39420397 39310341 39230321 38930273 38590235 38220211
37820201 37390201 37190207 37070217 36970280

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN


Read more
https://www.spc.noaa.gov/products/md/md1255.html