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Belmont, CA · San Mateo County
Right Now
Mostly Clear
Water
66°
Wind
11 mph
WSW
Gusts
16 mph
Pressure
30.00
falling
Forecast - Wed, Jun 24
High / Low
67° / 54°
Wind
8 mph
gusts 19 mph
Precip
0%
UV
8
Sunrise
12:49 PM
Sunset
3:34 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
Mon, Mon, Jun 29
Mon, Jun 29 scores 74/100 — Solunar 5/5, Wind 8 mph.
Best for Boating
Mon, Mon, Jun 29
Mon, Jun 29 scores 90/100 — Wind 8 mph, Rain 0%.
Best for Swimming
Wed, Wed, Jul 1
Wed, Jul 1 scores 70/100 — Air 65°F, Rain 0%.
Best for Paddling
Mon, Mon, Jun 29
Mon, Jun 29 scores 85/100 — Wind 8 mph, Rain 0%.
Ask the AI assistant about this week:
Swipe to see all 9 days
| Metric | Wed24 | Thu25 | Fri26 | Sat27 | Sun28 | Mon29 | Tue30 | Wed1 | Thu2 |
|---|---|---|---|---|---|---|---|---|---|
| Condition | Partly Cloudy | Partly Cloudy | Mostly Cloudy | Mostly Clear | Clear | Clear | Partly Cloudy | Partly Cloudy | Partly Cloudy |
| High / Low | 67°/54° | 66°/55° | 65°/54° | 63°/55° | 67°/53° | 69°/53° | 64°/52° | 65°/53° | 67°/55° |
| Precip | 0% | 0% | 24% | 15% | 0% | 0% | 0% | 0% | 0% |
| Wind | 12 mphgust 19 | 12 mphgust 22 | 10 mphgust 20 | 14 mphgust 27 | 10 mphgust 22 | 8 mphgust 16 | 9 mphgust 18 | 9 mphgust 18 | 9 mphgust 15 |
| Pressure | 29.98" stable | 29.93" falling | 29.95" rising | 29.98" rising | 29.91" falling | 29.90" stable | 29.90" stable | 29.92" rising | 29.96" rising |
| UV Index | 8 | 7 | 5 | 9 | 9 | 9 | 8 | 6 | 6 |
| Sunrise | 12:49 PM | 12:49 PM | 12:50 PM | 12:50 PM | 12:50 PM | 12:51 PM | 12:51 PM | 12:52 PM | 12:52 PM |
| Sunset | 3:34 AM | 3:34 AM | 3:34 AM | 3:34 AM | 3:34 AM | 3:34 AM | 3:34 AM | 3:34 AM | 3:34 AM |
| Bite Rating | 3/5first quarter | 2/5waxing gibbous | 2/5waxing gibbous | 3/5waxing gibbous | 3/5waxing gibbous | 5/5FULL | 4/5FULL | 3/5FULL | 2/5waning gibbous |
Today Read
Upper Crystal Springs ReservoirWind read
Calm
8 mph avg
Water read
66°
Warm-water bite
Air range
54° / 67°
today
Precip
0%
low concern
Today's forecast for Upper Crystal Springs Reservoir has calm wind, 54F to 67F air temperatures, 0% chance of precipitation, and 66F 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 9 live data sources for this lake — tap a stat or ask anything to see its work.
Fishing Forecast
first quarter
Major
3:53 AM - 6:23 AM
Minor
10:45 PM - 12:15 AM
Detailed temperature readings across your lake.
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Fish Species
5Water Temperature History
Current
69°
Jun 28
Low
45°
Feb 16
Average
61°
Last 12 Months
Warmest avg: July (67°F)
Coolest avg: February (51°F)
Rapid warming: February → March (+9°F)
Sharpest cooling: October → November (-11°F)
Wind speed, gusts, and pressure trends for trip timing.
Swipe days or tap points
7am - 6am
Peak Wind
12 mph
11pm
Peak Gust
19 mph
highest gust
Pressure
30.01 inHg
steady
Visibility
8 mi
64% 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
3/5first quarter
Water at 66°F -- warm-water species active.
Fish Species
5Nearby Lakes
FAQ
Upper Crystal Springs Reservoir covers 592.80 acres (0.93 square miles) with a maximum depth of 9.77 meters (~32 feet).
Upper Crystal Springs Reservoir is located in Belmont, San Mateo County, CA. It is accessible to the public for outdoor activities.