South Sister Summit, Oregon Weather
Viewpoint • Central Oregon
South Sister Summit weather at a glance
South Sister Summit is a viewpoint at 10,358 feet in Central Oregon. Notable features include viewpoint and wilderness.
Current conditions are 34°F, feeling like 22°F, with 15% humidity, winds near 13 mph, 7% cloud cover, and a 0% chance of precipitation. Cold and breezy and dry with some clouds.
The location-specific climate baseline shows an average daily high of 39°F and an average low of 27°F, with about 7.5 hours of sunshine per day and 1.8 hours of morning fog per day. Expected annual precipitation is approximately 71.9 inches.
Plan your week
10-Day Forecast
Hour by hour
Hourly Forecast
Current Conditions
Comfort Breakdown
Weather Maps
About the weather maps for South Sister Summit
Each preview is centered on South Sister Summit, with the red pin marking its approximate location. Satellite imagery provides cloud context, radar shows nearby precipitation, and the fog view shows the marine-layer or low-cloud field when that regional layer is available.
These images cover a wider area than the point forecast, so a nearby cloud or rain band may not be directly over South Sister Summit. Open a preview for the interactive map and its latest timestamp before making a weather-sensitive decision.
Nearby Temperature Comparison
Conditions at nearby Central Oregon destinations
Tip: Central Oregon temps can vary 20-30°F within a short distance due to microclimates.
Climate Dashboard
Current conditions vs. HRRR rolling destination baseline
What the South Sister Summit climate comparisons mean
These cards compare recent conditions at South Sister Summit with the available local baseline. Temperature and year-to-date rainfall use long-term normals when available; fog, sunshine, wind, and comfort use the matching recent or modeled baseline identified on each card.
Positive and negative differences describe how South Sister Summit departs from its own usual pattern. They should not be read as a direct comparison with another city or as a forecast beyond the period shown.
Historical Climate Data
Long-term weather patterns and climate data
Data sources: NOAA HRRR rolling destination baseline for recent temperature, precipitation, fog, cloud, wind, humidity, and sunshine signals.
Climate Overview
Based on HRRR rolling destination baseline (2024-10-01 to 2026-09-30)
🌟 Best Months to Visit
⚠️ Challenging Months
Monthly Breakdown
| Month | Comfort | High/Low | ☀️ Sun | 🌫️ Fog | 💧 Rain | Perfect |
|---|---|---|---|---|---|---|
| October 2024 | 56 | 40.6° / 28.7° | 5.9h | 7d | 3.45" | 9 |
| November 2024 | 31 | 26.4° / 16.4° | 2.5h | 19d | 18.11" | 0 |
| December 2024 | 33 | 28.5° / 16.9° | 3h | 14d | 22.14" | 0 |
| January 2025 | 47 | 30.5° / 17.5° | 5.7h | 6d | 7.78" | 0 |
| February 2025 | 36 | 22.3° / 9.9° | 3.6h | 12d | 10.41" | 0 |
| March 2025 | 37 | 25.4° / 15.2° | 4.6h | 15d | 13.42" | 0 |
| April 2025 | 56 | 32.2° / 18.3° | 9.2h | 6d | 1.81" | 0 |
| May 2025 | 57 | 37.2° / 24.1° | 10.1h | 12d | 1.4" | 3 |
| June 2025 | 70 | 45.3° / 32.8° | 12h | 4d | 1.24" | 9 |
| July 2025 | 87 | 57.7° / 43.5° | 12.1h | 1d | 0.16" | 28 |
| August 2025 | 87 | 57.9° / 44.5° | 11.3h | 2d | 0.29" | 23 |
| September 2025 | 77 | 54.6° / 41.3° | 8.7h | 4d | 1.34" | 20 |
| October 2025 | 49 | 36.3° / 26.2° | 6h | 13d | 6.35" | 2 |
| November 2025 | 44 | 33.1° / 24.9° | 4.7h | 9d | 4.69" | 0 |
| December 2025 | 33 | 30.5° / 21.1° | 2.6h | 18d | 19.01" | 0 |
| January 2026 | 45 | 31.9° / 21.5° | 5.2h | 10d | 4.7" | 0 |
| February 2026 | 43 | 26.6° / 15.5° | 4.8h | 13d | 7.7" | 0 |
| March 2026 | 43 | 31.3° / 19.8° | 5.8h | 14d | 6.38" | 0 |
| April 2026 | 51 | 31.7° / 18.4° | 8.2h | 9d | 5.99" | 0 |
| May 2026 | 61 | 42° / 29.3° | 10.7h | 6d | 3.02" | 6 |
| June 2026 | 70 | 48.4° / 34.7° | 10.1h | 6d | 1.6" | 17 |
| July 2026 | 88 | 58.5° / 43.8° | 12.3h | 0d | 0.26" | 29 |
| August 2026 | 91 | 58.8° / 44.2° | 11.7h | 0d | 0.04" | 30 |
| September 2026 | 66 | 45.8° / 33.7° | 8.2h | 6d | 2.14" | 13 |
Climate Trends
Average Temperature by Month
About the South Sister Summit climate charts
The temperature chart compares average monthly highs and lows at South Sister Summit, showing both the seasonal cycle and the typical day-to-night range. The comfort chart summarizes how often the combined weather pattern is favorable rather than judging temperature alone.
Precipitation shows the total recorded or modeled rainfall for each month at South Sister Summit. Sunshine compares average bright-sky hours with the daylight available, while fog shows the average number of morning fog or low-cloud hours per day. Switch between the chart tabs to compare the same months across each measure.
Hourly Temperature, Wind, and Cloud Cover Patterns
Average local hour by month from 2016-05-01 to 2026-05-01
How to read the temperature heatmap for South Sister Summit
This heatmap shows how average temperature at South Sister Summit changes by hour and month. Read left to right for the seasons and top to bottom for the time of day; warmer colors identify the usual afternoon peaks and cooler colors show overnight and winter lows.
Each cell combines one month with one local hour. Hover over or focus on a cell for its value and sample coverage; the red marker shows the current month and hour.
How to read the wind heatmap for South Sister Summit
This heatmap shows the typical hourly wind pattern at South Sister Summit through the year. It makes recurring afternoon wind, calmer overnight periods, and seasonal changes easier to compare than a single daily wind value.
Each cell combines one month with one local hour. Hover over or focus on a cell for its value and sample coverage; the red marker shows the current month and hour.
How to read the cloud cover heatmap for South Sister Summit
This heatmap shows average cloud cover at South Sister Summit for every month and hour. Use it to see whether cloudiness is mainly an overnight and morning pattern or commonly persists during the part of the day you plan to visit.
Each cell combines one month with one local hour. Hover over or focus on a cell for its value and sample coverage; the red marker shows the current month and hour.
Location Details
Frequently Asked Questions
Everything you need to know about weather and visiting South Sister Summit
What is the weather at South Sister Summit right now?
Current conditions at South Sister Summit are 34°F, feeling like 22°F, with 15% humidity, winds near 13 mph, 7% cloud cover, and a 0% chance of precipitation. Cold and breezy and dry with some clouds
What temperatures are typical at South Sister Summit?
The location-specific record for 2024-10-01 through 2026-09-30 shows an average daily high of 39°F and an average low of 27°F at South Sister Summit. These are averages across the year; the monthly climate table on this page shows the warmer and cooler seasons separately.
How much rain does South Sister Summit get?
The location-specific climate baseline estimates about 71.9 inches of precipitation and 126 days with measurable rain in a typical year at South Sister Summit. The monthly breakdown shows when that rain is most likely.
How often is South Sister Summit foggy?
South Sister Summit averages about 1.8 hours of morning fog per day across the location-specific climate baseline, with approximately 103 foggy days in a typical year. Fog varies considerably by season, so check the monthly breakdown and current forecast for visit planning.
What are the best months to visit South Sister Summit for comfortable weather?
Based on the destination's recorded comfort, temperature, sunshine, rain, and fog data, the strongest months are August 2026 (59°F/44°F average high/low and a 91 comfort score), July 2026 (59°F/44°F average high/low and a 88 comfort score), and July 2025 (58°F/44°F average high/low and a 87 comfort score). “Best” depends on the activity, so use the monthly table for the exact tradeoffs.
What kind of destination is South Sister Summit?
South Sister Summit is a viewpoint at 10,358 feet. Notable features include viewpoint and wilderness.