Lake Merwin

Lake Merwin

Na, WA

61°F
51°
4 mph63°/44°

Right Now

51°

Drizzle

Water

61°

Wind

4 mph

N

Gusts

9 mph

Pressure

29.98

steady

Forecast - Sun, Jun 7

7am
47°
10am
51°
1pm
58°
4pm
63°

High / Low

63° / 44°

Wind

2 mph

gusts 7 mph

Precip

24%

UV

5

Sunrise

12:20 PM

Sunset

3:58 AM

Today Read

Lake Merwin

Wind read

Calm

2 mph avg

Water read

61°

Cool-water mix

Air range

44° / 63°

today

Precip

24%

low concern

Today's forecast for Lake Merwin has calm wind, 44F to 63F air temperatures, 24% chance of precipitation, and 61F water.

AI lake plannerFishableChecking questions

Ask what to do at Lake Merwin today.

The planner reads this page's water temp, forecast, fish species, solunar timing, reports, and imagery context so you can decide what to throw, when to go, and when to move.

Today's AI read

Active-water pattern for Rainbow trout / Smallmouth bass

66 confidence

Active temps make wind edges, shallow cover, and feeding windows more important. Wind is not the main constraint, so timing and presentation can drive the plan. With a weak solunar score, favor stable weather windows.

Uses this lake data

Current water temp: 61°FWater temp history: 472 readingsHourly weather: 224 hoursSolunar timing: 2/5Fish species: 4 listedSatellite imagery: 407 captures

Trip read from the AI planner

Fishing Forecast

Last quarter

2/5

Major

1:09 PM - 3:39 PM

Minor

7:43 AM - 9:13 AM

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June 3, 2026

Fish Species

4

Water Temperature History

Current

67°

Jun 14

Low

38°

Feb 5

Average

54°

Last 12 Months

Warmest avg: July (71°F)

Coolest avg: February (39°F)

Rapid warming: AprilMay (+9°F)

Sharpest cooling: OctoberNovember (-13°F)

Weather Forecast

Wind speed, gusts, and pressure trends for trip timing.

Hourly Wind Forecast

7

12am - 11pm

Wind SpeedWind Gust
Tap points
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Peak Wind

5 mph

3pm

Peak Gust

7 mph

highest gust

Pressure

30.05 inHg

rising

Visibility

10 mi

34% clouds

Tap chart for details, swipe left or right for different days.Tap chart for details • Swipe for different days

Daily Pressure Forecast

Pressure
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Tap chart points for pressure details

Nearby Lakes

FAQ

About Lake Merwin

Lake Merwin covers 3840.00 acres (6.00 square miles)

Lake Merwin is located in Na, Cowlitz County, WA. It is accessible to the public for outdoor activities.