Round Valley Reservoir, NJ

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Outdoor scenery at Round Valley Reservoir
Round Valley Reservoir — photo by Dough4872, CC BY-SA 4.0, via Wikimedia Commons.

Today’s Forecast:

☁
48°F
High: 48° | Low: 36°
Current Temperature
Cloudy
Station: KSMQ
Observed at: 7:53 pm CST on 11/12/26
Wind: 5 mph | Humidity: 86%
Tonight:Rain showers likely before 1am, then rain. Cloudy, with a low around 36. Northeast wind 5 to 10 mph, with gusts as high as 25 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Friday:Rain. Cloudy, with a high near 45. North wind 5 to 10 mph, with gusts as high as 25 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
Friday Night:Rain likely before 11pm, then a slight chance of rain and snow between 11pm and midnight. Mostly cloudy, with a low around 30. Northwest wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.
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Today’s Report:

⛵ Boating

Not Recommended
  12 /100

Not Recommended for boating. High near 44°F. Rain forecast later today (98%). Light wind (10 mph). Temperatures outside comfort limits (44°F).

  • Temp: Unfavorable weather factor
  • Rain: Marginal weather factor
  • Wind: Favorable conditions
  • Thunderstorm: Favorable conditions
Tomorrow's Outlook:
Not Recommended 23/100
Not Recommended for boating. High near 47°F. Light wind (10 mph). Temperatures outside comfort limits (47°F).

🛶 Paddling

Not Recommended
  12 /100

Not Recommended for paddling. High near 44°F. Rain forecast later today (98%). Breezy winds (10 mph). Temperatures outside comfort limits (44°F).

  • Temp: Unfavorable weather factor
  • Rain: Marginal weather factor
  • Wind: Marginal weather factor
  • Thunderstorm: Favorable conditions
Tomorrow's Outlook:
Not Recommended 22/100
Not Recommended for paddling. High near 47°F. Breezy winds (10 mph). Temperatures outside comfort limits (47°F).

🐟 Fishing

Use Caution
  42 /100

Use Caution for fishing. High near 44°F. Rain forecast later today (98%). Light wind (10 mph).

  • Temp: Marginal weather factor
  • Rain: Marginal weather factor
  • Wind: Favorable conditions
  • Thunderstorm: Favorable conditions
Tomorrow's Outlook:
Excellent 85/100
Excellent for fishing. High near 47°F. Light wind (10 mph).

⛺ Camping

Use Caution
  42 /100

Use Caution for camping. High near 44°F. Rain forecast later today (98%). Light wind (10 mph).

  • Temp: Marginal weather factor
  • Rain: Marginal weather factor
  • Wind: Favorable conditions
  • Thunderstorm: Favorable conditions
Tomorrow's Outlook:
Excellent 88/100
Excellent for camping. High near 47°F. Light wind (10 mph).

🥾 Hiking

Use Caution
  42 /100

Use Caution for hiking. High near 44°F. Rain forecast later today (98%). Light wind (10 mph).

  • Temp: Marginal weather factor
  • Rain: Marginal weather factor
  • Wind: Favorable conditions
  • Thunderstorm: Favorable conditions
Tomorrow's Outlook:
Good 82/100
Good for hiking. High near 47°F. Light wind (10 mph).

About Round Valley Reservoir

Conditions shape the experience at Round Valley Reservoir, where visitors find a deep reservoir, boat launches, fishing water, trails, shoreline access, and wilderness camping.

Planning an Outing at Round Valley Reservoir

Build the day around water conditions, thunderstorm timing, daylight, and current access notices rather than relying on temperature alone.

Weather Tips for Round Valley Reservoir

  • Check water level, river stage or dam release, launch status, current, water temperature, and wind before putting in.
  • Open reservoirs build short steep waves quickly, while rivers may change because of rain well upstream.
  • Leave the water when thunder is heard and allow extra daylight for headwind, current, portage, or crowded ramps.
  • Verify park, campground, swimming, fishing, and water-quality notices before the drive.

Nearby Towns and Areas

Use this forecast as practical context for outdoor plans near:

  • Clinton
  • Lebanon
  • Annandale
  • Cushetunk Mountain
  • Spruce Run Reservoir
  • Hunterdon County

Adjust the Day to the Forecast

Choose the version of the outing that fits current wind, visibility, precipitation, temperature, water conditions, access, and daylight.

7-Day Forecast for Round Valley Reservoir

☁
48°F
High: 48° | Low: 36°
Current Temperature
Cloudy
Station: KSMQ
Observed at: 7:53 pm CST on 11/12/26
Wind: 5 mph | Humidity: 86%
Fri 🌧
45° 30°
98%
Sat ⛅
47° 32°
1%
Sun ⛅
49° 32°
0%
Mon ☀
51° 29°
0%
Tue ☀
54° 31°
0%
Wed ☀
60° 32°
0%
Thu ☀
61° --°
1%

7-Day High Temperature Trend

45° Fri 47° Sat 49° Sun 51° Mon 54° Tue 60° Wed 61° Thu

7-Day Low Temperature Trend

30° Fri 32° Sat 32° Sun 29° Mon 31° Tue 32° Wed 50° Thu

📊 7-Day Outdoor Outlook

Good Fair Poor 18 Fri 20 Sat 20 Sun 75 Mon 90 Tue 100 Wed 100 Thu
Forecast data from the National Weather Service  |  Last Updated: November 12, 2026 8:36 pm CST

Round Valley Reservoir Weather by Season

Winter

Winter at Round Valley Reservoir brings cold water, gusty fronts, occasional snow and ice, and limited services. Never assume ice is safe; use winter activities only where locally permitted and verified.

Spring

Spring water stays cold as rain raises levels and softens shoreline access. Wind, dam operations, current, and launch status deserve a fresh check before every outing.

Summer

Summer favors boating and paddling, but heat, afternoon lightning, algae or water-quality notices, and sudden gusts can shorten the day. An early launch usually offers the best margin. Open-water wind and launch availability are the main day-to-day planning variables here.

Fall

Fall often brings comfortable air and fishing weather, while cooling water, stronger fronts, foliage traffic, and shorter daylight increase the need for layers and conservative return times.

Key Climate Data Points

  • Annual average temperature: about 51–56°F using the nearest practical inland climate station.
  • Annual snowfall: generally about 15–30 inches, varying with elevation and distance from the coast.
  • Warmest months: July and August are normally warmest.
  • Coolest months: January is typically coolest.
  • Wettest season: Summer is often wettest because of thunderstorms and tropical moisture, although precipitation is distributed through the year.
  • Driest season: Fall is often driest, particularly from October into November.
  • Best outdoor window: Spring and fall usually provide the best balance of comfortable temperatures and reliable access.