207
AWUS01 KWNH 282354
FFGMPD
COZ000-290300-

Mesoscale Precipitation Discussion 0510
NWS Weather Prediction Center College Park MD
753 PM EDT Fri Jun 28 2024

Areas affected...Northern Colorado

Concerning...Heavy rainfall...Flash flooding possible

Valid 282352Z - 290300Z

SUMMARY...Training storms may cause localized flash flooding in
the terrain across Northern Colorado into this evening.

DISCUSSION... Training storms have developed across northern
Colorado in response to a strong shortwave tracking across
Wyoming. Unidirectional westerly flow, the strong shortwave, the
right entrance region of the jet, and still above normal levels of
atmospheric moisture with PWATs between 3/4 and 1 inch all are
supporting the storms. While the heaviest rains have been
sporadic, this has likely been due to the interaction with the
terrain. Soil moisture levels have been similarly sporadic based
on NASA sport soil moisture imagery, but several spots where the
training storms have set up have seen heavy rain in recent days.
SPC Mesoanalysis shows SBCape values between 1,000 and 2,000 J/kg,
which will support the continuation of the storms. A front draped
to the north of the storms over far southern Wyoming is acting as
a very effective northern gradient for the convection, as there`s
a sharp gradient to the north of the front with much lower
atmospheric moisture and almost no instability. This front may be
helping to focus the convection across this corridor of northern
Colorado.

The storms are expected to continue for the next few hours, with
gradually decreasing strength and coverage over this region
following sunset, which should result in decreasing instability as
well as departing forcing. HRRR guidance shows the storms will
significantly diminish in coverage after 03Z/9pm MDT.

Flash flooding should remain widely scattered since the storm
coverage is also widely scattered, and is most likely in areas
where redeveloping and training cells result in multiple rounds of
heavy rain over flood sensitive areas.

Wegman

...Please see www.wpc.ncep.noaa.gov for graphic product...

ATTN...WFO...BOU...GJT...PUB...

ATTN...RFC...ABRFC...CBRFC...MBRFC...NWC...

LAT...LON   40830432 40330397 40160493 39720588 39000644
            38490796 38970838 39610858 40270855 40650752
            40820544