Oregon Climate – July 2026 Update
Top 5 Cities: Portland, Salem, Eugene, Gresham, and Hillsboro
Summary
Oregon experienced a remarkably warm and dry summer spell, headlined by its 3rd driest May-July period in 77 years of records. High temperatures and severe rainfall deficits across the state have exacerbated drought conditions and heightened fire risks heading into late summer. This warmth coincides with a moderate El Niño forecast to peak at Very Strong in Sep-Nov, which historically leans towards warmer and drier conditions across the Pacific Northwest. Hotter-than-average conditions are expected to persist through late summer.
This month in numbers
The May-July 2026 season delivered exceptional heat and dryness across Oregon. The three-month average temperature reached 16.31°C (+2.0°C above the 1961-1990 baseline), ranking as the 3rd warmest May-July on record, while maximum temperatures averaged 24.56°C (+2.6°C anomaly), also placing 3rd highest. Total rainfall for May-July reached just 58.93 mm, which is 41.7 mm below baseline, making it the 3rd driest May-July on record (ranking 75th of 77 years). For July 2026 itself, the average temperature reached 20.33°C (+2.1°C anomaly), making it the 15th warmest such month on record, with maximum temperatures averaging 29.22°C and precipitation totalling only 6.1 mm.
What changed
The recent heat continues a broader warming trend in Oregon, where the long-term temperature rise stands at +0.98°C and the full year 2025 was the 2nd warmest on record at 9.87°C, behind only 2015. Oregon's July anomaly of +2.1°C outstripped the broader US average anomaly of +1.5°C for the month. Across a 12-month rolling window, Oregon ranks 27th out of 232 global regions tracked, with an anomaly of +2.41°C. Within NOAA's Northwest US climate region, Oregon's monthly anomaly was slightly lower than Idaho (+3.12°C) but above Washington (+1.88°C), as detailed at US Northwest.
What’s driving change?
The persistent heat and dryness have been reinforced by and localised , where parched soils lose their evaporative cooling capacity and trap solar warmth. Tropical Pacific conditions are also playing a role, with a moderate El Niño currently active that is forecast to peak at Very Strong in Sep-Nov, as tracked at ENSO. While El Niño historical teleconnections for the region show a modest 55% reliability towards drier and milder winters, current atmospheric patterns have already intensified dry spell conditions. All of Oregon's 1 wildfire tracked on our live map at Extreme Weather tracker occurred in the past month amid these dry conditions.
Looking ahead
Seasonal forecasts indicate that above-average temperatures and lingering drought conditions are likely to prevail across Oregon over the next 1-3 months.
Generated by Gemini from climate data and web sources
At a Glance
Temperature – Average
Climate Map – USUnited States
Source: NOAA Climate at a Glance — US states & climate regions (tavg, pcp), plus GPCC (Snow, water-equivalent). Anomalies are vs the 1961–1990 baseline. See methodology.
Typical Climate – Oregon
Köppen Csb · TemperateOregon has a temperate climate (Köppen Csb: Mediterranean - warm summer), with both a warm/cold cycle and a wet/dry cycle through the year. July is typically the warmest month, averaging 20.1°C, while January is the coldest at 0.9°C. Annual precipitation averages around 781mm, concentrated mostly in the wet season.
Monthly climate normals (2016–2025) - bar colour and height show average temperature, the shaded area shows average monthly rain, with snow (water-equivalent) shown separately.
Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).
Long-Term Trends
Combined Timeline – Oregon
Precipitation, Sunshine, Frost and Snow are converted to standard deviations from their own average so they can share an axis with Temperature.
Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).
Heatwave Days – Oregon
Warm Spell Duration Index (WSDI) - days in a 6+ day run above the local 90th-percentile temperature for that time of year.
Data: World Bank Climate Change Knowledge Portal (ERA5-derived). Refreshed roughly 1-2x/year, ~7-8 months behind present.
Year-on-Year Trends
The 4byo Climate Helix – Oregon
Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).
Monthly Temperature – Oregon
Background lines show the last 40 years (plus the record year and its opposite, wherever they fall).
Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).
Records – Oregon
NOAA National Centers for Environmental Information (frost: World Bank CCKP; snow: GPCC (DWD)) - Anomalies vs 1901-2000 mean
Shifting Seasons
Warm/cold + wet/dryKöppen Dsb · ContinentalOregon has both a clear warm/cold cycle (±9.6°C) and a wet/dry cycle (12× wet:dry ratio). Both sides of the annual rhythm are shown below.
Monthly precipitation climatology. A “wet month” exceeds the baseline monthly mean (dashed gold line). Biggest month-to-month shift: Jan (-23 mm, -17%).
Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).
Climate Systems
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Emissions & Energy
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Data Sources
Data Sources for Oregon
Every figure on this page is sourced from official, openly published climate datasets. Anomalies are calculated against the 1961–1990 baseline (temperature) and 1991–2020 (rainfall, sunshine, frost) - see the Methodology & Sources page for the complete dataset list and update calendar.
Statewide monthly temperature and precipitation (nClimDiv).
Frost Days and Heatwave Days (Warm Spell Duration Index), ERA5-derived. World Bank Climate Change Knowledge Portal.
Monthly snow water-equivalent, Global Precipitation Climatology Centre (DWD).
FAQs
FAQs
How is the climate in Oregon changing?
Oregon is warming in line with the rest of the world. The page above shows the latest monthly temperature anomaly versus the 1961-1990 baseline, the long-term annual trend, and the region's rank in the historical record. The headline panel also shows the long-term trend rate per decade and the warmest and coolest years on file.
What is the climate like in Oregon?
Oregon has a temperate climate (Köppen Csb: Mediterranean - warm summer), with both a warm/cold cycle and a wet/dry cycle through the year. July is typically the warmest month, averaging 20.1°C, while January is the coldest at 0.9°C. Annual precipitation averages around 781mm, concentrated mostly in the wet season.
Where does the climate data for Oregon come from?
Climate data for Oregon comes from NOAA Climate at a Glance (temperature and precipitation), refreshed every month, when the upstream temperature and rainfall data are refreshed.
What is the climate baseline used on this page?
Anomalies on this page are calculated against the 1961-1990 climatological baseline, which is the standard reference period used by the Met Office, NOAA, IPCC and most national climate services. Some panels also show the source-native 1901-2000 (NOAA) or 1991-2020 (WMO) baselines for verification. See Methodology & Sources for the full reference.
Which areas does the Oregon climate data cover?
The Oregon climate profile covers Portland, Salem, Eugene, Gresham and surrounding areas. Oregon climate data from NOAA Climate at a Glance
How often is the Oregon climate update refreshed?
The Oregon climate update is refreshed monthly, typically a few days after the previous month closes and the upstream provider (Met Office HadUK-Grid, NOAA Climate at a Glance, Copernicus ERA5 or the Global Carbon Project) publishes its update. See the Climate Rankings for cross-region comparisons.
What counts as a Heatwave Day on the Oregon climate page?
Heatwave Days use the Warm Spell Duration Index (WSDI) - the WMO/ETCCDI-standard heatwave measure: days that are part of a run of 6 or more consecutive days above the local 90th-percentile temperature for that calendar day. The 90th-percentile threshold varies by time of year (a hot day in January is judged differently to one in July) but is fixed to the 1961-1990 baseline for every year shown - it does not shift as the climate warms, which is why Heatwave Days trend upward over time.
Does the Oregon climate page include frost and snow data?
Yes. Frost Days (days with a minimum temperature below 0°C, World Bank CCKP) and snow water-equivalent (GPCC) are shown alongside temperature and precipitation, each measured against the 1961-1990 baseline where a like-for-like historical comparison is available.