325
AWUS01 KWNH 190202
FFGMPD
WIZ000-MNZ000-IAZ000-NEZ000-SDZ000-190800-

Mesoscale Precipitation Discussion 0753
NWS Weather Prediction Center College Park MD
1000 PM EDT Fri Jul 18 2025

Areas affected...Upper Midwest

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

Valid 190200Z - 190800Z

SUMMARY...A well-organized convective complex is expected to
develop and drop generally down to the southeast overnight with
impacts to portions of northeast NE, eastern SD, southern MN and
northwest IA going through the overnight hours.

DISCUSSION...GOES-E WV imagery shows ejecting shortwave energy
across the northern Plains aiming for the Upper Midwest with a
favorable right-entrance region of the upper jet in place that
will facilitate strong upscale growth of an MCS overnight.

Multiple waves of low pressure traversing the region along a
frontal zone with be interacting with a moist and very unstable
airmass pooling north across the region. This will be facilitated
by an increasingly strong south-southwest low-level jet reaching
30 to 40+ kts between 03Z and 06Z, and this will favor organized
upscale growth of convection with assistance from strong effective
bulk shear approaching 50 kts. Already radar imagery is showing
shower and thunderstorm activity developing and expanding in
coverage across portions of central and southwest MN.

The latest RAP analysis shows MUCAPE values of 2000 to 3000 J/kg
across eastern SD, southwest MN and western IA, and the nose of
this instability will help yield a substantial area of elevated
convection over southern MN and eventually areas of northern IA
going through the overnight hours. However, warm sector convection
is expected ahead of the cold front farther back to the southwest
including areas of eastern SD down through northeast NE.

Rainfall rates with the stronger storms tonight as they organize
are expected to reach up to 2 inches/hour. There will be some
cell-merger and localized cell-training concerns that may help
support some storm totals of 3 to 5 inches.

Scattered areas of flash flooding will be possible going through
the overnight hours as this convective complex grows upscale and
drops gradually down to the southeast across the Upper Midwest.

Orrison

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

ATTN...WFO...ABR...ARX...DMX...FSD...LBF...MPX...OAX...

ATTN...RFC...KRF...MSR...NWC...

LAT...LON   45429375 44809248 43539256 42689406 42099645
            42149820 43039870 44019737 44999619