Hydrologic Outlook issued May 14 at 2:17PM CDT by NWS Bismarck ND

ESFBIS

A substantial series of rainfall events will be spreading across
North Dakota through the remainder of the week. Here is a table of
select cities and probabilities for select amounts of precipitation.

Table 1. Probability of rainfall amounts through May 16th.

Probability Probability Probability
City of 2 inches of 3 inches of 4 inches
———————————————————-
Crosby 76 51 28
Williston 68 36 9
Bottineau 70 33 4
Minot 97 90 69
Garrison 89 72 47
Washburn 88 70 43
Dickinson 77 51 21
Bowman 50 19 4
Bismarck 78 46 11
Linton 64 28 6
Jamestown 23 3 0
Rugby 74 34 3

As shown in the above probabilities, the axis for higher rainfall
amounts generally follows U.S. Highway 83 from Bismarck up through
Minot. Since the highest likelihood for training thunderstorms is
limited to the southern half of the state, this suggests the higher
probability for localized minor flooding would be from McLean county
and south through Mercer, Oliver, Morton, Grant, Sioux, Emmons,
Burleigh and Sheridan counties.

In general, rivers and streams west of the Missouri River (Cedar
Creek, Cannonball, Heart, and Knife) will receive the highest
rainfall totals in the lower portion of their respective watersheds.
This will help minimize the risk of any forecast location from
exceeding its flood stage. However, a few watersheds will bear the
brunt of the heaviest rainfall over their entirety. These include,
but are not limited to, Sweet Briar, Square Butte and Otter creeks
in Morton County along with Beaver Creek in Emmons county, Apple
Creek in Burleigh County, and Painted Woods Creek in McLean County.
People along these and other smaller streams should be wary of the
potential for rising water over the remainder of the week.

Farther north, Minot and most of the Souris River Basin will also
receive significant rainfall over the coming days. However, due to
the very limited risk of training thunderstorms in the northern
portion of the state, the creeks and coulees will experience rising
water levels, but the rainfall will be spread out over a long enough
duration to minimize runoff given the abnormally dry soils.

In short, while there is always at least some risk of problematic
high water with systems that produce as much rain as in the current
forecast, the finer details suggest that wet period will be much
more beneficial than a risk. Nonetheless, the expected totals and
the possibility of training thunderstorms will bear keeping an eye
on the water for those who live near small streams across a good
portion of North Dakota.