Sylvan Lake Conditions: Weather, Water & Fishing

Sylvan Lake Conditions: Weather, Water & Fishing | LakeRadar

24-Hour Hourly Weather & Wind Timeline

← Scroll Timeline →

Hour-by-hour forecast for Sylvan Lake, next 24 hours
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)	51°	50°	47°	47°	47°	47°	47°	47°	51°	61°	67°	70°	72°	74°	77°	78°	76°	72°	67°	65°	63°	62°	61°	61°
Wind (kts)	2	4	5	6	7	8	8	8	8	7	7	8	11	11	12	12	11	7	7	9	8	9	10	11
Direction	SW	W	W	W	W	W	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW
Gusts (kts)	2	11	12	14	15	16	17	16	18	19	20	21	22	22	24	24	23	19	17	18	19	19	21	23
Precip %	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	1%	1%	1%	1%	1%	1%

ForecastView official hourly forecast

Hour-by-hour forecast for Sylvan Lake, next 24 hours
Time	Temp	Wind	Gusts	Precip	Cloud	Condition
Fri, 12 AM MDT	51°F	2 mph SW (225°)	2 mph	0%	3%	Clear
Fri, 1 AM MDT	50°F	5 mph W (270°)	13 mph	0%	4%	Clear
Fri, 2 AM MDT	47°F	6 mph W (270°)	14 mph	0%	5%	Clear
Fri, 3 AM MDT	47°F	7 mph W (270°)	16 mph	0%	8%	Mostly Clear
Fri, 4 AM MDT	47°F	8 mph W (270°)	17 mph	0%	7%	Mostly Clear
Fri, 5 AM MDT	47°F	9 mph W (270°)	18 mph	0%	5%	Clear
Fri, 6 AM MDT	47°F	9 mph SW (225°)	20 mph	0%	11%	Sunny
Fri, 7 AM MDT	47°F	9 mph SW (225°)	18 mph	0%	14%	Sunny
Fri, 8 AM MDT	51°F	9 mph SW (225°)	21 mph	0%	7%	Sunny
Fri, 9 AM MDT	61°F	8 mph SW (225°)	22 mph	0%	3%	Sunny
Fri, 10 AM MDT	67°F	8 mph SW (225°)	23 mph	0%	2%	Sunny
Fri, 11 AM MDT	70°F	9 mph SW (225°)	24 mph	0%	3%	Sunny
Fri, 12 PM MDT	72°F	13 mph SW (225°)	25 mph	0%	4%	Sunny
Fri, 1 PM MDT	74°F	13 mph SW (225°)	25 mph	0%	4%	Sunny
Fri, 2 PM MDT	77°F	14 mph SW (225°)	28 mph	0%	3%	Sunny
Fri, 3 PM MDT	78°F	14 mph SW (225°)	28 mph	0%	4%	Sunny
Fri, 4 PM MDT	76°F	13 mph SW (225°)	27 mph	0%	8%	Sunny
Fri, 5 PM MDT	72°F	8 mph SW (225°)	22 mph	0%	5%	Sunny
Fri, 6 PM MDT	67°F	8 mph SW (225°)	20 mph	1%	8%	Mostly Clear
Fri, 7 PM MDT	65°F	10 mph SW (225°)	21 mph	1%	7%	Mostly Clear
Fri, 8 PM MDT	63°F	9 mph SW (225°)	22 mph	1%	9%	Mostly Clear
Fri, 9 PM MDT	62°F	10 mph SW (225°)	22 mph	1%	8%	Mostly Clear
Fri, 10 PM MDT	61°F	12 mph SW (225°)	24 mph	1%	9%	Mostly Clear
Fri, 11 PM MDT	61°F	13 mph SW (225°)	27 mph	1%	11%	Mostly Clear
Sat, 12 AM MDT	60°F	14 mph SW (225°)	27 mph	1%	11%	Mostly Clear

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.

7-Day Weather & Wind Forecast

← Scroll Forecast →

Seven-day forecast periods for Sylvan Lake from the official forecast source
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)	47°	78°	56°	76°	49°	60°	37°	51°	36°	53°	38°	50°	37°	47°
Wind	W 2 to 9 mph	SW 8 to 14 mph	SW 8 to 15 mph	SW 5 to 14 mph	W 3 to 7 mph	S 6 mph	NE 7 mph	SW 6 mph	S 5 mph	S 6 mph	S 7 mph	NW 8 mph	NW 7 to 21 mph	NW 13 to 21 mph
Gusts	18 mph	28 mph	29 mph	27 mph	18 mph	17 mph	18 mph	18 mph	15 mph	20 mph	20 mph	27 mph	40 mph	40 mph
Precip %	0%	0%	1%	1%	18%	7%	44%	24%	39%	24%	65%	64%	60%	36%
Forecast	Mostly Clear	Sunny	Mostly Clear	Sunny	Slight Chance Light Rain then Mostly Cloudy	Mostly Cloudy	Chance Light Rain	Slight Chance Light Rain then Partly Sunny	Chance Light Rain	Slight Chance Light Rain	Rain Likely	Rain Likely	Rain Likely then Chance Rain And Snow	Chance Rain And Snow

Forecast periods from official National Weather Service grid. Detailed 7-Day & Hourly Forecast →

Fishing Conditions & Outlook

Solunar windows, water thermocline & species tactics

Score 82 · Good

Good for fishing (82/100), from 5 available inputs. Supporting this: Wind 2 mph from the southwest. 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.

Prime Solunar Window

4:00 PM MDT – 10:00 PM MDT

Water Layer Temp

Sensor Pending

Surface Chop

4 mph

Barometer Trend

30.05 inHg

Verified Game Fish Species (6):

🐟Largemouth Bass🐟Brook Trout🐟Brown Trout🐟Rock Bass

View Full Fishing Forecast & Solunar Times →Fishing methodology →

Boating & Sailing Outlook

Surface chop, sustained knots, gusts & launch facilities

Boating 78Sailing 53

Motorized Boating

Launch Access

Good for boating (78/100), from 4 available inputs. Supporting this: Wind 2 mph from the southwest. Gusts to 2 mph. Working against it: Active severe alert: Red Flag 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.

Surface state: Glass / Light Ripple

Boating Outlook & Ramps Directory →

Sailing & Wind Trim

3 kts (4 mph)

Poor for sailing (53/100), from 4 available inputs. Supporting this: Gusts are within 0 mph of sustained wind, so the breeze is steady. 0% chance of precipitation. Working against it: Active severe alert: Red Flag Warning. Wind 2 mph is light; expect limited sailing. Not available from a verified source for this lake: visibility. Confidence is high (88%).

Kayaking, Paddling & Swimming

Paddle drag, thermal comfort & cold water immersion safety

Paddling 79Swimming --

Paddlecraft Readiness

Glassy Surface

Good for kayaking (79/100), from 5 available inputs. Supporting this: Wind 2 mph from the southwest. Gusts to 2 mph. Working against it: Active severe alert: Red Flag Warning. Confidence is high (90%).

Immersion: Wear USCG Approved Life Jacket

Paddlecraft Guidelines & Launch Points →

Swimming & Immersion

Not monitored

Water temperature is not available from a verified source for this lake. No swimming score is shown without it.

Water Temperature & 30-Day History →

Lake Guide & Verified Facts

Visitor Essentials, Seasonal Guide & Hydrographic Profile

Offering scenic water views and diverse outdoor activities, Sylvan Lake is a premier destination in SD for boaters, anglers, and nature enthusiasts. Its waters support healthy gamefish populations alongside seasonal paddlecraft exploration. Review local launch regulations and safety guidelines before putting in for the day.

Surface Area

18 acres

Max Depth

30 ft

Surface Elevation

6,145 ft MSL

Managing Authority

State & Local Authorities

Classification

Reservoir

State Jurisdiction

Visitor Essentials · Know Before You Go

Fishing Licensing (SDGFP)

Valid freshwater sport fishing license issued by South Dakota Game, Fish and Parks (SDGFP) is required for anglers age 16+. Digital license on mobile is accepted.

Boating Biosecurity & Registration

Current motorized watercraft registration mandatory. Practice Clean, Drain & Dry protocols: drain all livewells and inspect props before launching. Life jackets required for all passengers.

Public Recreation & Access Pass

Public shoreline and boating access managed by State & Local Authorities. Verify seasonal gate hours, launch fees, and parking rules before travel.

Primary Water Recreation Profile

Low-wake cruising, electric-troll fishing craft, and quiet-water exploration. Target gamefish include Largemouth Bass, Brook Trout, Brown Trout, Rock Bass. Morning hours typically provide optimal glassy conditions for kayak and stand-up paddleboard (SUP) touring.

Seasonal Recreation & Climate Windows

Summer Peak (Jun–Aug)Peak Season

Warm water temperatures, peak swimming, active watersports, and open full-service campgrounds. Highest weekly attendance; plan early arrivals on summer weekends.

Spring & Fall ShoulderPrime Angling

Spring pre-spawn and fall feeding transitions create prime trophy angling conditions. Cooler air, lower boat traffic, and vibrant seasonal shoreline foliage.

Winter Season (Nov–Mar)Off-Season

High-altitude mountain winter climate (elevation 6,145 ft MSL). Freezing temperatures, potential snowpack or ice cover, and reduced seasonal amenities. Winter safety caution advised.

Get Directions (GPS) ↗Managing Authority Portal ↗

All geographical facts sourced from official agency recordsView sources →

Sylvan Lake Conditions

Red Flag Warning

Quick Conditions

LakeRadar Score

24-Hour Hourly Weather & Wind Timeline

7-Day Weather & Wind Forecast

Water Level (USGS)

Water Temperature (Surface)

Fishing Conditions & Outlook

Boating & Sailing Outlook

Kayaking, Paddling & Swimming

Interactive Map & Navigation Radar

Coordinates and access points

Public Access & Facilities

Boating & Water Regulations

Lake Guide & Verified Facts

Official alerts

Red Flag Warning

Quick Conditions

LakeRadar Score

24-Hour Hourly Weather & Wind Timeline

7-Day Weather & Wind Forecast

Water Level (USGS)

Water Temperature (Surface)

Fishing Conditions & Outlook

Boating & Sailing Outlook

Kayaking, Paddling & Swimming

Interactive Map & Navigation Radar

Coordinates and access points

Public Access & Facilities

Boating & Water Regulations

Lake Guide & Verified Facts

Related Lakes

Sources and methodology