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Official National Weather Service (NWS) point forecast and real-time wind conditions for Lake Koocanusa (Montana). 24-hour hour-by-hour wind timelines, peak gusts, watercraft recreation safety thresholds, and 7-day marine outlook.
Today: High 66°F · Low 42°F
Peak gusts: 15 mph · Lake surface chop expected
Humidity: 36% · Barometer: 30.00 inHg
USGS water monitoring available for Lake Koocanusa.
Fair for boating (67/100), from 4 available inputs. Supporting this: No active official alerts for this lake. 1% chance of precipitation. Working against it: Gusts to 31 mph. 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.
Good for fishing (77/100), from 5 available inputs. Supporting this: 1% chance of precipitation. Sky is partly cloudy (32% cloud cover). 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.
Fair for kayaking (67/100), from 5 available inputs. Supporting this: No active official alerts for this lake. 1% chance of precipitation. Working against it: Gusts to 31 mph. Confidence is high (90%).
Water temperature is not available from a verified source for this lake. No swimming score is shown without it. Supporting this: No active official alerts for this lake. 1% chance of precipitation. Not available from a verified source for this lake: water temperature.
| Time | Air Temp | Wind (mph) | Direction | Peak Gusts | Rain Chance | Sky & Conditions |
|---|---|---|---|---|---|---|
| 1 PM | 65°F | 15 mph | SW | ⚡ 31 mph | 1% | Mostly Sunny |
| 2 PM | 65°F | 15 mph | SW | ⚡ 32 mph | 5% | Mostly Sunny |
| 3 PM | 66°F | 15 mph | W | ⚡ 28 mph | 14% | Partly Sunny |
| 4 PM | 65°F | 15 mph | W | ⚡ 28 mph | 20% | Slight Chance Light Rain |
| 5 PM | 63°F | 14 mph | SW | ⚡ 28 mph | 6% | Mostly Cloudy |
| 6 PM | 61°F | 13 mph | SW | ⚡ 27 mph | 16% | Slight Chance Light Rain |
| 7 PM | 57°F | 10 mph | SW | ⚡ 27 mph | 24% | Slight Chance Light Rain |
| 8 PM | 54°F | 9 mph | SW | ⚡ 27 mph | 24% | Slight Chance Light Rain |
| 9 PM | 53°F | 13 mph | SW | ⚡ 22 mph | 15% | Slight Chance Light Rain |
| 10 PM | 51°F | 13 mph | SW | ⚡ 21 mph | 11% | Mostly Cloudy |
| 11 PM | 50°F | 13 mph | SW | ⚡ 18 mph | 4% | Mostly Cloudy |
| 12 AM | 49°F | 7 mph | SW | ⚡ 15 mph | 4% | Mostly Cloudy |
| 1 AM | 46°F | 7 mph | SW | ⚡ 13 mph | 1% | Mostly Cloudy |
| 2 AM | 46°F | 7 mph | SW | ⚡ 10 mph | 0% | Mostly Cloudy |
| 3 AM | 45°F | 3 mph | SW | ⚡ 9 mph | 0% | Partly Cloudy |
| 4 AM | 44°F | 2 mph | SW | ⚡ 8 mph | 4% | Mostly Cloudy |
| 5 AM | 44°F | 2 mph | SW | ⚡ 7 mph | 3% | Partly Cloudy |
| 6 AM | 42°F | 2 mph | NE | ⚡ 7 mph | 8% | Partly Sunny |
| 7 AM | 41°F | 2 mph | NE | ⚡ 7 mph | 31% | Chance Light Rain |
| 8 AM | 40°F | 2 mph | N | ⚡ 6 mph | 47% | Chance Light Rain |
| 9 AM | 40°F | 2 mph | W | ⚡ 22 mph | 53% | Chance Rain And Snow |
| 10 AM | 44°F | 2 mph | N | ⚡ 22 mph | 59% | Rain And Snow Likely |
| 11 AM | 46°F | 3 mph | E | ⚡ 22 mph | 41% | Chance Light Rain |
| 12 PM | 47°F | 14 mph | NE | ⚡ 23 mph | 29% | Chance Light Rain |
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.
A slight chance of rain between 4pm and 5pm. Partly sunny, with a high near 67. Southwest wind around 15 mph, with gusts as high as 32 mph. Chance of precipitation is 20%.
A slight chance of rain before 10pm. Mostly cloudy, with a low around 40. Southwest wind 2 to 13 mph, with gusts as high as 26 mph. Chance of precipitation is 20%.
A chance of rain between 7am and 9am, then rain and snow likely between 9am and 5pm. Mostly cloudy, with a high near 51. North northeast wind 2 to 21 mph. Chance of precipitation is 60%.
Partly cloudy, with a low around 32. Northeast wind 8 to 20 mph, with gusts as high as 29 mph.
A slight chance of snow before noon. Mostly cloudy, with a high near 45. Northeast wind around 10 mph, with gusts as high as 22 mph. Chance of precipitation is 20%.
Partly cloudy, with a low around 28.
Sunny, with a high near 54.
Mostly clear, with a low around 32.
Sunny, with a high near 58.
Partly cloudy, with a low around 36.
Mostly sunny, with a high near 58.
Partly cloudy, with a low around 37.
Mostly sunny, with a high near 60.
Partly cloudy, with a low around 38.
Lake Koocanusa currently reports 56°F with wind velocity near 9 mph from the S. 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 Lake Koocanusa 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 MSO) high-resolution numerical point-forecast API. LakeRadar uses the official gridpoint for Lake Koocanusa 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 Lake Koocanusa Water Level & Temperature page.
View Lake Koocanusa Water Level & Temperature →