Montana · river
Sun River at Simms
USGS monitoring location. Launch access and paddling suitability have not been verified.
Weather comparison · not a safety rating
Favorable weather
Weather score out of 100
Weather only. This is a monitoring station, not a verified launch. Access, hazards and suitable flow are unknown.
Weather observation: Tue, 29 Sep 2026 04:15:00 GMT.
River observation: Tue, 29 Sep 2026 03:30:00 GMT.
Page checked: Tue, 29 Sep 2026 04:23:21 GMT. Readings older than one hour are not used for the current score.
Wind
7 mph
gusting to 15 mph
Air temp
52°F
0% chance of rain
River flow
364 cfs
very high for this date
Weather outlook
Sunday · 100
Mon
74
72°
Tue
40
71°
Wed
61
66°
Thu
95
58°
Fri
58
66°
Sat
83
63°
Sun
100
63°
Best
Compares forecast wind, air temperature and rain. Does not assess river flow, swell, currents, water temperature or launch access. All times are local to this location.
Wind, next 12 hours
mph| Hour | Wind (mph) | Gusts (mph) |
|---|---|---|
| 10p | 7 | 15 |
| 11p | 7 | 14 |
| 12a | 6 | 14 |
| 1a | 5 | 15 |
| 2a | 7 | 15 |
| 3a | 2 | 11 |
| 4a | 6 | 17 |
| 5a | 9 | 21 |
| 6a | 12 | 22 |
| 7a | 12 | 22 |
| 8a | 12 | 20 |
| 9a | 14 | 22 |
Is this flow normal for September 29?
Today's 364 cfs is 172% above the median for this date — which counts as very high water here.
The median flow on this date is 134 cfs, across 59 years of USGS record at this gauge. Whether that is runnable depends on the stretch — this is context, not a recommendation.
Why this score
- Wind — 7 mph — light wind at the forecast location±0
- Cold — 52°F air temperature — cool weather; water temperature is not measured-12
We don't have launch notes for this one
This page is built from the USGS gauge at this location, and uses available public readings. We haven't verified where to put in, what the hazards are, or whether this stretch is legal or sensible to paddle. We'd rather say that than invent it. The links below are where to find out.
We also don't have a verified safe-flow range here, so the Paddle Score reflects weather only. Judge the flow number against local knowledge, not against our score.
Do your own homework
We show you live conditions. For local knowledge — where to put in, what the hazards are, whether it's worth the drive — here's where paddlers actually talk about this water. We don't vet these sources; check the dates and judge for yourself.
- Paddler discussion on Reddit
Trip reports and local warnings, straight from the source
- Search American Whitewater
Rapid classifications and gauge-linked run descriptions
- Satellite view and access roads
Check parking, put-ins, and what the banks actually look like
- Video from this water
The fastest way to see the character of a run before you drive
- USGS gauge 06085800
Full hydrograph, historical flows, and station metadata