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Official National Weather Service (NWS) point forecast and real-time wind conditions for Lake Decatur (Illinois). 24-hour hour-by-hour wind timelines, peak gusts, watercraft recreation safety thresholds, and 7-day marine outlook.
Today: High 81°F · Low 61°F
Peak gusts: 6 mph · Lake surface chop expected
Humidity: 44% · Barometer: 30.09 inHg
USGS water monitoring available for Lake Decatur.
Excellent for boating (98/100), from 4 available inputs. Supporting this: Wind 3 mph from the southwest. Gusts to 5 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.
Excellent for fishing (94/100), from 5 available inputs. Supporting this: Wind 3 mph from the southwest. Dusk hours (18:00 local). 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.
Excellent for kayaking (98/100), from 5 available inputs. Supporting this: Wind 3 mph from the southwest. Gusts to 5 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. Air temperature 76°F. Not available from a verified source for this lake: water temperature.
| Time | Air Temp | Wind (mph) | Direction | Peak Gusts | Rain Chance | Sky & Conditions |
|---|---|---|---|---|---|---|
| 6 PM | 76°F | 3 mph | SW | ⚡ 5 mph | 0% | Clear |
| 7 PM | 71°F | 3 mph | S | ⚡ 5 mph | 0% | Clear |
| 8 PM | 68°F | 3 mph | S | ⚡ 5 mph | 0% | Clear |
| 9 PM | 66°F | 3 mph | S | ⚡ 6 mph | 0% | Clear |
| 10 PM | 64°F | 5 mph | S | ⚡ 6 mph | 0% | Clear |
| 11 PM | 63°F | 5 mph | S | ⚡ 7 mph | 0% | Mostly Clear |
| 12 AM | 62°F | 5 mph | S | ⚡ 8 mph | 0% | Partly Cloudy |
| 1 AM | 62°F | 6 mph | S | ⚡ 10 mph | 0% | Partly Cloudy |
| 2 AM | 62°F | 7 mph | S | ⚡ 10 mph | 0% | Partly Cloudy |
| 3 AM | 63°F | 7 mph | S | ⚡ 12 mph | 0% | Partly Cloudy |
| 4 AM | 63°F | 7 mph | S | ⚡ 13 mph | 0% | Partly Cloudy |
| 5 AM | 61°F | 7 mph | SW | ⚡ 13 mph | 0% | Partly Cloudy |
| 6 AM | 62°F | 7 mph | SW | ⚡ 12 mph | 0% | Sunny |
| 7 AM | 63°F | 7 mph | SW | ⚡ 12 mph | 1% | Mostly Sunny |
| 8 AM | 65°F | 8 mph | SW | ⚡ 13 mph | 2% | Sunny |
| 9 AM | 72°F | 9 mph | SW | ⚡ 15 mph | 2% | Mostly Sunny |
| 10 AM | 77°F | 10 mph | SW | ⚡ 17 mph | 2% | Mostly Sunny |
| 11 AM | 81°F | 12 mph | SW | ⚡ 18 mph | 3% | Sunny |
| 12 PM | 84°F | 13 mph | SW | ⚡ 18 mph | 4% | Sunny |
| 1 PM | 88°F | 14 mph | SW | ⚡ 20 mph | 4% | Sunny |
| 2 PM | 89°F | 14 mph | SW | ⚡ 21 mph | 4% | Sunny |
| 3 PM | 90°F | 15 mph | SW | ⚡ 21 mph | 3% | Sunny |
| 4 PM | 90°F | 15 mph | SW | ⚡ 21 mph | 3% | Sunny |
| 5 PM | 89°F | 13 mph | SW | ⚡ 20 mph | 3% | Sunny |
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.
Mostly clear, with a low around 61. South wind 3 to 7 mph.
Sunny, with a high near 90. Southwest wind 7 to 15 mph, with gusts as high as 21 mph.
Clear, with a low around 71. Southwest wind 9 to 13 mph, with gusts as high as 18 mph.
Sunny, with a high near 91. Southwest wind 9 to 13 mph, with gusts as high as 20 mph.
A chance of showers and thunderstorms between 7pm and 10pm, then a chance of showers and thunderstorms between 10pm and 4am, then a chance of showers and thunderstorms. Partly cloudy, with a low around 68. Southwest wind around 7 mph. Chance of precipitation is 50%. New rainfall amounts between a quarter and half of an inch possible.
Showers and thunderstorms. Mostly cloudy, with a high near 80. Northwest wind 3 to 7 mph. Chance of precipitation is 80%. New rainfall amounts between three quarters and one inch possible.
Showers and thunderstorms. Mostly cloudy, with a low around 59. Northeast wind 8 to 12 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.
Showers and thunderstorms. Mostly cloudy, with a high near 74. Chance of precipitation is 80%.
Showers and thunderstorms before 7pm, then a chance of showers and thunderstorms between 7pm and 1am, then a chance of showers and thunderstorms. Mostly cloudy, with a low around 52. Chance of precipitation is 80%.
A chance of showers and thunderstorms before 7am. Partly sunny, with a high near 64.
Partly cloudy, with a low around 37.
Sunny, with a high near 58.
Clear, with a low around 35.
Sunny, with a high near 65.
Lake Decatur currently reports 80°F with wind velocity near 3 mph from the SW. 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 Decatur 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 ILX) high-resolution numerical point-forecast API. LakeRadar uses the official gridpoint for Lake Decatur 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 Decatur Water Level & Temperature page.
View Lake Decatur Water Level & Temperature →