Mesoscale Precipitation Discussion 0860
NWS Weather Prediction Center College Park MD
147 PM EDT Mon Jul 27 2026

Areas affected...Mountains of Colorado and North-central New
Mexico and Adj. Eastern Utah...

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

Valid 271745Z - 272345Z

SUMMARY...Enhanced moisture across the Colorado Rockies and
favorable upper-level forcing/outflow should allow for increased
coverage of thunderstorm activity this afternoon. Slow cell
motions and rates of 1"/hr may promote localized spots of 1-1.5"
totals and possible incidents of scattered localized flash
flooding.

DISCUSSION...GOES-E satellite animated imagery suite shows the
center of a compact shortwave over north-central CO at this time,
with an impressive downstream 50kt jet streak indicated by dense
mid to upper-level cloud shield (and embedded shallower convective
elements) across NE CO, SE WY into W NEB. The combined features
remain on the northern periphery of a strong synoptic ridge
centered along the SE CO/SW KS boarder; leaving another favorable
day for convective activity starting with normal mountain
circulation.

CIRA LPW and RAP analysis show 7-10C Tds and enhanced moisture
from the San Francisco Plateau across the central CO Rockies,
while surface Tds are in the upper 50s in lower elevations of SW
CO and even remain in the low 50s to mid-50s in the central
terrain, which combined with moderate moisture noted even in the
500-300mb resulting in TPW values over 1.25" in the Valleys and
even building into the North Park region later this afternoon,
nearing 1" values even to the highest peaks which is clearly well
above normal and near the highest percentiles of all-periods.
East of the Rockies, moisture flux still remains upsloping
building ever so slightly as a surface pressure trof remains in
solid positioning just south of the Lake/Palmer Divide into
West-central KS at this time. All in all, a very moist
environment in place suggests an increased potential in at least
coverage, even as far south as the Sangre de Cristo Range.

Currently full insolation in all but the northern Colorado Plains,
Wyoming and Far northwest CO will help to expand instability
fields across the region with RAP forecast of 750-1250 J/kg across
the northeast Rockies in 3-4 hours with most of the region above
500 J/kg even into the San Juan Range. Initial thunderstorm
activity will be driven by normal mountain circulation convergence
(as already noted along the Sangre de Cristo with LightningCast
already over 70% for CI in the next hour). Initial rates of
.5-.75" will translate toward .75-1"/hr with maybe a highly
isolated 1.25"/hr rate toward mid-afternoon, with best potential
near and downstream of the shortwave in the northern Colorado
Ranges given slightly better dynamics. Spots of 1-1.5", perhaps
locally as high as 2" are possible though 00z. Given rocky,
complex terrain and scattered older burn scars, scattered
incidents of flash flooding are considered possible through this
afternoon into evening.

Gallina

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

ATTN...RFC...FWR...KRF...STR...TUA...NWC...

LAT...LON 40960689 40950660 40840599 40310526 39470497
38650488 37970478 37330443 36650455 36030486
35540516 35570579 35560638 35570689 35950711
36510682 37070689 37200740 37260808 37560875
38030921 38580946 39000944 39460897 39740855
40130831 40620814 40920757