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Mercer, WI · Iron County
Right Now
Cloudy
Water
69°
Wind
3 mph
SW
Gusts
7 mph
Pressure
30.05
falling
Forecast - Thu, Jun 25
High / Low
67° / 55°
Wind
2 mph
gusts 10 mph
Precip
92%
UV
4
Sunrise
10:10 AM
Sunset
1:56 AM
Every forecast metric for the week ahead — plus AI-picked best days for fishing, boating, swimming, and paddling.
Instant recommendations based on wind, precip, pressure, solunar, and temperature.
Best for Fishing
Sat, Sat, Jun 27
Sat, Jun 27 scores 70/100 — Solunar 3/5, Wind 6 mph.
Best for Boating
Sat, Sat, Jun 27
Sat, Jun 27 scores 90/100 — Wind 6 mph, Rain 0%.
Best for Swimming
Sat, Sat, Jun 27
Sat, Jun 27 scores 80/100 — Air 75°F, Rain 0%.
Best for Paddling
Sat, Sat, Jun 27
Sat, Jun 27 scores 85/100 — Wind 6 mph, Rain 0%.
Ask the AI assistant about this week:
Swipe to see all 9 days
| Metric | Thu25 | Fri26 | Sat27 | Sun28 | Mon29 | Tue30 | Wed1 | Thu2 | Fri3 |
|---|---|---|---|---|---|---|---|---|---|
| Condition | Rain | Drizzle | Mostly Cloudy | Partly Cloudy | Rain | Thunderstorms | Thunderstorms | Thunderstorms | Drizzle |
| High / Low | 67°/55° | 70°/50° | 75°/50° | 77°/53° | 78°/59° | 89°/68° | 87°/71° | 85°/67° | 89°/69° |
| Precip | 92% | 63% | 0% | 29% | 53% | 43% | 44% | 56% | 44% |
| Wind | 6 mphgust 10 | 5 mphgust 10 | 6 mphgust 12 | 8 mphgust 19 | 13 mphgust 25 | 13 mphgust 25 | 10 mphgust 22 | 8 mphgust 18 | 7 mphgust 16 |
| Pressure | 29.98" stable | 30.00" rising | 30.05" rising | 29.98" falling | 29.88" falling | 29.77" falling | 29.81" rising | 29.91" rising | 30.00" rising |
| UV Index | 4 | 5 | 5 | 6 | 6 | 6 | 6 | 5 | 7 |
| Sunrise | 10:10 AM | 10:10 AM | 10:10 AM | 10:11 AM | 10:11 AM | 10:12 AM | 10:12 AM | 10:13 AM | 10:14 AM |
| Sunset | 1:56 AM | 1:56 AM | 1:55 AM | 1:55 AM | 1:55 AM | 1:55 AM | 1:55 AM | 1:55 AM | 1:54 AM |
| Bite Rating | 3/5waxing gibbous | 2/5waxing gibbous | 3/5waxing gibbous | 2/5waxing gibbous | 5/5FULL | 4/5FULL | 3/5FULL | 3/5waning gibbous | 3/5waning gibbous |
Today Read
Grand Portage LakeWind read
Calm
2 mph avg
Water read
69°
Warm-water bite
Air range
55° / 67°
today
Precip
92%
watch timing
Today's forecast for Grand Portage Lake has calm wind, 55F to 67F air temperatures, 92% chance of precipitation, and 69F water.
AI read · today
Active temps make wind edges, shallow cover, and feeding windows more important. The planning constraint is finding the right window.
Reads 8 live data sources for this lake — tap a stat or ask anything to see its work.
Fishing Forecast
waxing gibbous
Major
2:26 AM - 4:56 AM
Minor
10:01 PM - 11:31 PM
Detailed temperature readings across your lake.
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Water Temperature History
Current
69°
Jul 5
Low
32°
Feb 27
Average
54°
Last 12 Months
Warmest avg: July (72°F)
Coolest avg: March (37°F)
Rapid warming: April → May (+12°F)
Sharpest cooling: August → September (-9°F)
Wind speed, gusts, and pressure trends for trip timing.
Swipe days or tap points
5am - 4am
Peak Wind
8 mph
5pm
Peak Gust
18 mph
highest gust
Pressure
30.04 inHg
steady
Visibility
10 mi
52% clouds
Tap chart for details, swipe left or right for different days.Tap chart for details • Swipe for different days
Pressure stability helps plan windows
Tap chart points for pressure details
Nearby Lakes
Fishing Forecast
3/5waxing gibbous
Water at 69°F -- warm-water species active.
Nearby Lakes
FAQ
Grand Portage Lake covers 148.00 acres (0.23 square miles) with a maximum depth of 10.05 meters (~33 feet).
Grand Portage Lake is located in Mercer, Iron County, WI. It is accessible to the public for outdoor activities.