Union Hill· North Sierra· conditions updating now
Open the map →

Union Hill

Peak · 1,902 ft · North Sierra corridor

Union Hill rises at 1,902 feet in the North Sierra corridor near Lake Oroville. This exposed peak offers views across the reservoir and surrounding foothills; wind and afternoon thermals drive most conditions.

Today
35
NoGo Score · Go · good
Temp
61°F
Wind
7 mph
Vis
11 mi
Precip
0.00"
AQI
40
Cloud
96%

Union Hill sits open and windy, especially on the lake-facing slopes. Mornings are calmer and cooler; by mid-afternoon, thermal winds push across the ridgeline. The 30-day average wind is 6 mph, but afternoon gusts to 13 mph force most paddlers and hikers off by early afternoon.

Over the last 30 days, Union Hill has averaged a NoGo Score of 35, with temperatures around 57 degrees and winds averaging 6 mph. Conditions have ranged from very open (score 5) to moderately constrained (score 50). The week ahead will follow the same pattern: watch for afternoon wind buildup by mid-day, and plan morning-only visits if you're sensitive to exposure or crowding.

30 days back / 7 days forward

NoGo Score
avg 29 · today 35
NoGo Score trend for Union Hill: 30-day average 29, range 7 to 50; 7 days of forecastLine chart showing nogo score over 29 historical days and 7 days of forecast.
30-day average 29 (good); range 7 on Apr 13 to 50 on Apr 23. 7-day forecast trends slightly worse.
Wind
avg 6 · today 4mph
Wind speed trend for Union Hill: 30-day average 6 mph, peak 9 mph on Apr 21Line chart showing wind over 29 historical days and 7 days of forecast.
30-day average 6 mph; peak 9 mph on Apr 21. Week ahead peaks at 5 mph on May 10.
Temperature
avg 59 · today 61°F
Temperature trend for Union Hill: 30-day average 59°F, range 52 to 69°FLine chart showing temperature over 29 historical days and 7 days of forecast.
30-day average 59°F; range 52 (Apr 21) to 69 (Apr 17). Trending warmer.
Crowding
avg 5 · today 9
Crowding trend for Union Hill: typically quietLine chart showing crowding over 29 historical days and 7 days of forecast.
Typically quiet (avg 5); peak 12 on Apr 5.

Today's score by factor

Weather2
Crowding21
Avalanche35
Fire0
Traffic
Air quality8
Trails5
Seasonality41

About Union Hill

Union Hill crowns the ridgeline north of Lake Oroville reservoir in Butte County, roughly 90 minutes northeast of Sacramento via California Highway 99 and Highway 70. The peak sits at 1,902 feet elevation, making it accessible year-round from the foothills below. Vehicle access is limited; most visitors approach from the Oroville area via local roads or from the Thermalito spillway region. The location appeals to hikers, peak baggers, and views-focused visitors rather than technical climbers. Parking is informal along county roads; no developed trailhead facility exists.

Temperature and wind define Union Hill's character. The 30-day average is 57 degrees Fahrenheit, with the year-round range spanning 45 to 74 degrees. Winter and early spring are cool and often wet; late spring through early fall are drier. Wind averages 6 mph over 30 days but gusts to 13 mph in the afternoons when thermals off the lake intensify. Morning windows before 11 a.m. are typically calmer. Crowding is light year-round (5-person average), but weekends near major holidays or opening of Highway 120 access to the north can see brief surges. The site has avalanche terrain; winter approaches after heavy snow require awareness of slope stability on steeper sections.

Union Hill suits hikers comfortable with open ridgeline exposure and afternoon wind. Experienced visitors arrive by early morning, summit by late morning, and descend before thermal winds peak. The peak offers 360-degree views of Oroville reservoir, the Butte County foothills, and the Sierra crest on clear days. Winter access is feasible but technical after significant snowpack; spring conditions can be muddy. Summer is reliably dry but hot by afternoon. The site is not ideal for paddlers or lake-based users because the overlook does not provide safe water access; the main draw is ridge hiking and photography.

Nearby alternatives include Table Mountain (just west, lower elevation, better for shorter hikes) and the Oroville Dam overlook area (more developed parking, fewer views but easier access). The North Sierra corridor transitions from foothills to higher elevations north of Highway 120; Union Hill represents the upper boundary of the lower-elevation landscape. Visitors seeking similar ridge exposure with higher elevation should consider the peaks around Highway 120 and the Feather River drainage to the north.

Best times to visit Union Hill

Best day
Tuesday morning before 11 a.m.
Best season
Late September through October
Watch for
Afternoon thermal wind; winter snow on steeper slopes

Nearby

Crystal Hill
1.5 mi · Peak
Island Bar Hill
3.0 mi · Peak
Stringtown Mountain
4.1 mi · Peak
Kanaka Peak
4.2 mi · Peak
Big Bald Rock
4.4 mi · Peak
Little Bald Rock
5.4 mi · Peak