Loading page content…
Loading page content…
Loading lake conditions…
Island Park Reservoir is a reservoir in Idaho. Its recorded surface area is approximately 7,280 acres. Coverage here includes an hourly and 7-day forecast, wind and gust outlook, and activity scores for boating, paddling, and swimming. If you are planning a trip, Henrys Lake are also nearby. This page combines the live forecast, wind, and conditions for Island Park Reservoir so you can plan a visit.
Updated
No active alerts for this lake as of the last check (Oct 9, 12:42 AM MDT). Alerts are re-checked automatically; see the official source for updates.
Overall Good (87/100) across 4 activities. Best right now: Boating (98/100).
How the score is calculated →Best excellent fishing window, averaging 90/100 across these hours. Wind 9 mph from the south-southwest. Dusk hours (19:00 local). Derived from the hourly forecast; official alerts are not forecast and are checked separately.
| Metric | 6a | 7a | 8a | 9a | 10a | 11a | 12p | 1p | 2p | 3p | 4p | 5p | 6p | 7p | 8p | 9p | 10p | 11p | 12a | 1a | 2a | 3a | 4a | 5a |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Temp (°F) | 42° | 41° | 39° | 38° | 37° | 36° | 35° | 35° | 35° | 41° | 53° | 60° | 65° | 68° | 70° | 72° | 70° | 70° | 68° | 62° | 57° | 53° | 50° | 48° |
| Wind (kts) | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 3 | 5 | 7 | 9 | 10 | 11 | 11 | 11 | 9 | 8 | 9 | 9 | 7 | 4 |
| Direction | NE | NE | E | E | E | E | E | E | SE | SE | S | S | S | SW | SW | SW | SW | SW | SW | SW | SW | SW | S | S |
| Gusts (kts) | 5 | 5 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 5 | 7 | 12 | 16 | 19 | 21 | 22 | 23 | 23 | 21 | 21 | 21 | 20 | 18 | 12 |
| Precip % | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 0% | 1% | 1% | 1% | 1% | 1% | 1% | 2% |
| Time | Temp | Wind | Gusts | Precip | Cloud | Condition |
|---|---|---|---|---|---|---|
| Fri, 12 AM MDT | 42°F | 2 mph NNE (23°) | 6 mph | 0% | 26% | Partly Cloudy |
| Fri, 1 AM MDT | 41°F | 1 mph NE (45°) | 6 mph | 0% | 29% | Partly Cloudy |
| Fri, 2 AM MDT | 39°F | 1 mph ENE (68°) | 5 mph | 0% | 21% | Mostly Clear |
| Fri, 3 AM MDT | 38°F | 1 mph ENE (68°) | 5 mph | 0% | 24% | Mostly Clear |
| Fri, 4 AM MDT | 37°F | 1 mph E (90°) | 5 mph | 0% | 22% | Mostly Clear |
| Fri, 5 AM MDT | 36°F | 1 mph E (90°) | 5 mph | 0% | 17% | Mostly Clear |
| Fri, 6 AM MDT | 35°F | 1 mph E (90°) | 5 mph | 0% | 15% | Sunny |
| Fri, 7 AM MDT | 35°F | 1 mph E (90°) | 5 mph | 0% | 28% | Mostly Sunny |
| Fri, 8 AM MDT | 35°F | 1 mph ESE (113°) | 5 mph | 0% | 23% | Sunny |
| Fri, 9 AM MDT | 41°F | 2 mph SE (135°) | 6 mph | 0% | 4% | Sunny |
| Fri, 10 AM MDT | 53°F | 3 mph S (180°) | 8 mph | 0% | 1% | Sunny |
| Fri, 11 AM MDT | 60°F | 6 mph S (180°) | 14 mph | 0% | 1% | Sunny |
| Fri, 12 PM MDT | 65°F | 8 mph S (180°) | 18 mph | 0% | 2% | Sunny |
| Fri, 1 PM MDT | 68°F | 10 mph SSW (203°) | 22 mph | 0% | 3% | Sunny |
| Fri, 2 PM MDT | 70°F | 12 mph SSW (203°) | 24 mph | 0% | 5% | Sunny |
| Fri, 3 PM MDT | 72°F | 13 mph SSW (203°) | 25 mph | 0% | 16% | Sunny |
| Fri, 4 PM MDT | 70°F | 13 mph SSW (203°) | 27 mph | 0% | 8% | Sunny |
| Fri, 5 PM MDT | 70°F | 13 mph SW (225°) | 27 mph | 1% | 8% | Sunny |
| Fri, 6 PM MDT | 68°F | 10 mph SSW (203°) | 24 mph | 1% | 4% | Clear |
| Fri, 7 PM MDT | 62°F | 9 mph SSW (203°) | 24 mph | 1% | 23% | Mostly Clear |
| Fri, 8 PM MDT | 57°F | 10 mph SW (225°) | 24 mph | 1% | 16% | Mostly Clear |
| Fri, 9 PM MDT | 53°F | 10 mph SW (225°) | 23 mph | 1% | 19% | Mostly Clear |
| Fri, 10 PM MDT | 50°F | 8 mph S (180°) | 21 mph | 1% | 39% | Partly Cloudy |
| Fri, 11 PM MDT | 48°F | 5 mph S (180°) | 14 mph | 2% | 48% | Partly Cloudy |
| Sat, 12 AM MDT | 46°F | 3 mph SW (225°) | 10 mph | 2% | 46% | Partly Cloudy |
Official National Weather Service hourly forecast. Showing 10 of 25 hours. Wind arrows point the way the wind is blowing; the compass point and degrees show where it comes from.
| Period | Overnight October 9, 2026 | Friday October 9, 2026 | Friday Night October 9, 2026 | Saturday October 10, 2026 | Saturday Night October 10, 2026 | Sunday October 11, 2026 | Sunday Night October 11, 2026 | Columbus Day October 12, 2026 | Monday Night October 12, 2026 | Tuesday October 13, 2026 | Tuesday Night October 13, 2026 | Wednesday October 14, 2026 | Wednesday Night October 14, 2026 | Thursday October 15, 2026 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Temp (°F) | 35° | 72° | 39° | 59° | 36° | 50° | 32° | 51° | 30° | 54° | 27° | 51° | 25° | 51° |
| Wind | ENE 2 mph | S 1 to 13 mph | SSW 1 to 10 mph | SSW 3 to 12 mph | ESE 6 mph | SE 6 mph | NNE 3 to 10 mph | SSW 5 to 8 mph | ESE 2 mph | S 1 to 5 mph | WSW 5 mph | WSW 3 to 7 mph | W 2 to 6 mph | NNW 2 to 6 mph |
| Gusts | 6 mph | 27 mph | 24 mph | 24 mph | 16 mph | 15 mph | 23 mph | 20 mph | 9 mph | 14 mph | 12 mph | 17 mph | 16 mph | 8 mph |
| Precip % | 0% | 1% | 24% | 83% | 99% | 100% | 97% | 93% | 61% | 51% | 51% | 32% | 35% | 16% |
| Forecast |
Good for fishing (83/100), from 5 available inputs. Supporting this: Wind 2 mph from the north-northeast. 0% chance of precipitation. 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 boating (98/100), from 4 available inputs. Supporting this: Wind 2 mph from the north-northeast. Gusts to 6 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.
Fair for sailing (70/100), from 4 available inputs. Supporting this: Gusts are within 4 mph of sustained wind, so the breeze is steady. No active official alerts for this lake. Working against it: Wind 2 mph is light; expect limited sailing. Not available from a verified source for this lake: visibility. Confidence is high (88%).
Excellent for kayaking (96/100), from 5 available inputs. Supporting this: Wind 2 mph from the north-northeast. Gusts to 6 mph. Confidence is high (90%).
Water temperature is not available from a verified source for this lake. No swimming score is shown without it.
Loading interactive map…
Individual boat ramp GPS coordinates are maintained under the jurisdiction of ID Parks & Wildlife Authority. Public boaters should verify seasonal launch water levels, gate hours, and daily vehicle/vessel fees before traveling.
Nestled within ID, Island Park Reservoir offers extensive shoreline access and dependable waters for public recreation. The lake accommodates a wide variety of activities including waterskiing, pontoon cruising, and bank angling. Facility management and regional habitat protection are overseen by state and local natural resource agencies.
Valid freshwater sport fishing license issued by Idaho Department of Fish and Game (IDFG) is required for anglers age 14+. Digital license on mobile is accepted.
Mandatory Clean, Drain & Dry inspection. Out-of-area craft require on-site Aquatic Invasive Species (AIS Quagga/Zebra) inspection or decontamination before launch. USCG life jackets required for all.
Public shoreline and boating access managed by State & Local Authorities. Verify seasonal gate hours, launch fees, and parking rules before travel.
High-speed motorboating, pontoon cruising, wakeboarding, and water skiing across main channels. Target gamefish include Rainbow Trout, Mountain Whitefish, Brook Trout, Kokanee Salmon. Morning hours typically provide optimal glassy conditions for kayak and stand-up paddleboard (SUP) touring.
Warm water temperatures, peak swimming, active watersports, and open full-service campgrounds. Highest weekly attendance; plan early arrivals on summer weekends.
Spring pre-spawn and fall feeding transitions create prime trophy angling conditions. Cooler air, lower boat traffic, and vibrant seasonal shoreline foliage.
Northern cold winter conditions with freezing air temperatures and potential surface ice formation. Ramps and water systems may be winterized. Confirm open status before visiting.
No external source rows are cited by the data currently shown on this page.
Updated
Scores are heuristics, not safety guarantees. LakeRadar scores summarize available conditions and are not a substitute for official warnings, local rules, or on-water judgment.
All telemetry for Island Park Reservoir is synchronized directly from authorized federal and state monitoring networks (USGS, NWS, NOAA, and state environmental authorities). Observations are strictly instrumented readings — unmonitored sensors are transparently disclosed rather than synthetic estimates.
Last source audit: Oct 9, 12:42 AM MDT