Hydrologic Outlook

Hydrologic Outlook
MTC001-007-013-031-043-049-057-059-262200-

Hydrologic Outlook
National Weather Service Great Falls MT
454 PM MDT Mon Aug 25 2025

...Widespread rainfall and embedded thunderstorms expected over
Southwest and portions of Central Montana Tuesday night through
Friday...

Monsoon moisture will slowly move northward and bring periods of
widespread rain and embedded thunderstorms to Southwest and portions
of Central Montana Tuesday night through Friday. Localized heavier
downpours in excess of a half inch per hour can be expected with the
heavier cells in addition to the general four day storm totals
between a quarter to an inch and a half. The most persistent and
heaviest rainfall is expected along and south of I90 on Wednesday
and Thursday.

Impacts will mostly be limited to sensitive burn scars or other
normally flood prone locations or areas of steep terrain and may
include instances of localized flooding, debris flows, and rock
slides.

Those considering any backcountry travel for Wednesday and Thursday
of this week should be prepared for periods of excessive rainfall,
muddy roads, and potential localized flooding.
$$

RG