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Official National Weather Service (NWS) point forecast and real-time wind conditions for Saint Mary Lake (Montana). 24-hour hour-by-hour wind timelines, peak gusts, watercraft recreation safety thresholds, and 7-day marine outlook.
Winter Storm Warning issued October 10 at 4:13PM MDT until October 12 at 6:00AM MDT by NWS Great Falls MT
Today: High 27°F · Low 24°F
Peak gusts: 24 mph · Lake surface chop expected
Humidity: 92% · Barometer: 29.77 inHg
USGS water monitoring available for Saint Mary Lake.
Winter Storm Warning issued October 10 at 4:13PM MDT until October 12 at 6:00AM MDT by NWS Great Falls MT
Very Poor / Avoid for boating (20/100), from 4 available inputs. Working against it: Gusts to 40 mph. Active severe alert: Winter Storm Warning. Not available from a verified source for this lake: visibility and conditions, verified water access. Confidence is moderate (84%) because some inputs are unavailable or older than ideal.
Poor for fishing (44/100), from 5 available inputs. Supporting this: Overnight hours (22:00 local). Sky is overcast (98% cloud cover). Working against it: 96% chance of precipitation is likely. Wind 23 mph from the north-northeast. Not available from a verified source for this lake: pressure trend, water temperature. Confidence is moderate (74%) because some inputs are unavailable or older than ideal.
Very Poor / Avoid for kayaking (20/100), from 5 available inputs. Working against it: Gusts to 40 mph. Active severe alert: Winter Storm Warning. Confidence is high (90%).
Water temperature is not available from a verified source for this lake. No swimming score is shown without it. Working against it: Active severe alert: Winter Storm Warning. Air temperature 27°F. Not available from a verified source for this lake: water temperature.
| Time | Air Temp | Wind (mph) | Direction | Peak Gusts | Rain Chance | Sky & Conditions |
|---|---|---|---|---|---|---|
| 10 PM | 27°F | 23 mph | NE | ⚡ 40 mph | 96% | Snow And Patchy Blowing Snow |
| 11 PM | 26°F | 23 mph | NE | ⚡ 39 mph | 97% | Snow And Patchy Blowing Snow |
| 12 AM | 25°F | 23 mph | NE | ⚡ 38 mph | 96% | Snow And Patchy Blowing Snow |
| 1 AM | 25°F | 23 mph | NE | ⚡ 38 mph | 93% | Snow And Patchy Blowing Snow |
| 2 AM | 25°F | 22 mph | NE | ⚡ 37 mph | 96% | Snow And Patchy Blowing Snow |
| 3 AM | 24°F | 22 mph | NE | ⚡ 36 mph | 93% | Snow And Patchy Blowing Snow |
| 4 AM | 24°F | 22 mph | NE | ⚡ 37 mph | 96% | Snow And Patchy Blowing Snow |
| 5 AM | 24°F | 22 mph | NE | ⚡ 37 mph | 94% | Snow And Patchy Blowing Snow |
| 6 AM | 24°F | 22 mph | NE | ⚡ 37 mph | 96% | Snow And Patchy Blowing Snow |
| 7 AM | 24°F | 22 mph | NE | ⚡ 37 mph | 95% | Snow And Patchy Blowing Snow |
| 8 AM | 24°F | 21 mph | NE | ⚡ 35 mph | 91% | Snow And Patchy Blowing Snow |
| 9 AM | 24°F | 21 mph | NE | ⚡ 33 mph | 88% | Snow And Patchy Blowing Snow |
| 10 AM | 25°F | 20 mph | NE | ⚡ 32 mph | 93% | Snow And Patchy Blowing Snow |
| 11 AM | 26°F | 20 mph | NE | ⚡ 31 mph | 93% | Snow And Patchy Blowing Snow |
| 12 PM | 27°F | 18 mph | NE | ⚡ 30 mph | 97% | Snow And Patchy Blowing Snow |
| 1 PM | 27°F | 17 mph | NE | ⚡ 29 mph | 92% | Snow And Patchy Blowing Snow |
| 2 PM | 27°F | 17 mph | NE | ⚡ 28 mph | 84% | Snow And Patchy Blowing Snow |
| 3 PM | 27°F | 16 mph | NE | ⚡ 27 mph | 83% | Snow |
| 4 PM | 26°F | 16 mph | NE | ⚡ 25 mph | 75% | Light Snow |
| 5 PM | 26°F | 15 mph | NE | ⚡ 24 mph | 67% | Light Snow Likely |
| 6 PM | 25°F | 15 mph | NE | ⚡ 23 mph | 59% | Light Snow Likely |
| 7 PM | 25°F | 15 mph | NE | ⚡ 23 mph | 66% | Light Snow Likely |
| 8 PM | 24°F | 15 mph | NE | ⚡ 23 mph | 73% | Light Snow Likely |
| 9 PM | 24°F | 15 mph | NE | ⚡ 24 mph | 80% | Light Snow |
Mirror-like to gentle rippled water. Optimal conditions for paddleboarding, kayaking, swimming, and beginner water skiing or wakeboarding.
Pleasant breeze with small wavelets. Great for sailing, pleasure cruising, pontoon boats, and trolling for trout and bass.
Moderate waves with whitecaps likely. Requires skilled boat handling; kayaks, canoes, and stand-up paddleboards should stay close to sheltered bays.
Steep waves, cold spray, and hazardous open water. Avoid small craft voyages. Always check official National Weather Service lake wind advisories.
Snow and patchy blowing snow. Cloudy. Low around 19, with temperatures rising to around 24 overnight. North northeast wind 20 to 23 mph, with gusts as high as 40 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 5 inches possible.
Snow and patchy blowing snow. Cloudy, with a high near 27. Northeast wind 15 to 22 mph, with gusts as high as 37 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 5 inches possible.
Snow. Cloudy, with a low around 18. Northeast wind 8 to 15 mph, with gusts as high as 24 mph. Chance of precipitation is 90%. New snow accumulation of 1 to 2 inches possible.
A slight chance of snow before noon. Partly sunny, with a high near 38. South southwest wind 5 to 8 mph. Chance of precipitation is 20%. New snow accumulation of less than half an inch possible.
Partly cloudy, with a low around 22. Southwest wind 5 to 10 mph, with gusts as high as 21 mph.
Sunny, with a high near 47. West southwest wind 6 to 9 mph.
Mostly clear, with a low around 26. West southwest wind 5 to 13 mph, with gusts as high as 21 mph.
Sunny, with a high near 49. West southwest wind around 14 mph, with gusts as high as 23 mph.
A slight chance of rain after midnight. Partly cloudy, with a low around 29.
A slight chance of rain before 9am, then a slight chance of snow between 9am and noon. Mostly sunny, with a high near 51.
Partly cloudy, with a low around 29.
Sunny, with a high near 57.
Partly cloudy, with a low around 36.
Mostly sunny, with a high near 59.
Saint Mary Lake currently reports 28°F with wind velocity near 11 mph from the E. Atmospheric forecasts and 24-hour hour-by-hour wind timelines are updated hourly from the National Weather Service gridpoint matching the lake's coordinates.
At Saint Mary Lake and surrounding mountain valleys, diurnal heating of the surrounding terrain causes strong thermal pressure differentials known locally as afternoon breezes (such as the Washoe Zephyr at Lake Tahoe). Wind speeds typically peak between 1:00 PM and 5:00 PM before calming near sunset.
For stand-up paddleboarding (SUP), canoeing, and light kayaks, winds under 7 mph (light breeze) offer the safest, glassiest surface conditions. Between 8–14 mph, small wavelets develop, suitable for sailboats and powerboats. Winds exceeding 15 mph create steep whitecaps and rapid drift; winds over 21 mph warrant small craft warnings.
All weather and wind telemetry is fetched directly from the National Weather Service (NOAA - WFO TFX) high-resolution numerical point-forecast API. LakeRadar uses the official gridpoint for Saint Mary Lake without artificial smoothing or third-party estimates.
Yes. Live hydrological sensor readings, 30-day elevation histories, full-pool benchmarks, and USGS station provenance are available on our dedicated Saint Mary Lake Water Level & Temperature page.
View Saint Mary Lake Water Level & Temperature →