127
AWUS01 KWNH 070404
FFGMPD
NDZ000-MTZ000-070900-

Mesoscale Precipitation Discussion 0346
NWS Weather Prediction Center College Park MD
1203 AM EDT Sun Jun 07 2026

Areas affected...Northeast MT...Far Northwest ND

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

Valid 070403Z - 070900Z

SUMMARY...Very heavy and locally training showers and
thunderstorms over the next few hours may pose a concern for at
least some isolated areas of flash flooding.

DISCUSSION...The latest GOES-W IR satellite imagery along with
radar data shows an axis of heavy showers and thunderstorms
generally growing upscale across northeast MT and far northwest
ND, The activity is focusing along a well-defined frontal zone as
a wave of low pressure ejects northeastward along it.

Strongly convergent flow into the front with the aid of a
nocturnally enhanced south-southeast low-level of 40 to 50+ kts
coupled with strong instability characterized by MLCAPE values
near 2500 J/kg will continue to support organized convection over
the next few hours. This will include some supercell thunderstorms
which with the instability is being supported by strong effective
bulk shear locally exceeding 50 kts.

The PWs are on the order of 1.0 to 1.25 inches, and locally as
high as about 2 standard deviations above normal with the aid of
the low-level jet. This enhanced moisture transport and organized
level of convection over the next few hours will support rainfall
rates of 1 to 2 inches/hour quite easily. Some cell-training
concerns already in place with the activity aligned nearly
parallel to the deeper layer steering flow, and this may foster
some localized rainfall totals of 2 to 4 inches.

Some isolated areas of flash flooding will be possible given these
rainfall totals.

Orrison

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

ATTN...WFO...BIS...GGW...

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

LAT...LON   49960200 49010217 47300465 46920595 47400641
            48600548 49070485 49890323