Weather and Climate
Summary and Forecast
November 2026 Report
Gregory V. Jones, Ph.D.
November 3, 2026
Summary:
- Mild to warmer than average* for most of the western US during October.
- Strong subtropical flow and warmer than average ocean temperatures brought significant precipitation and coastal erosion to Southern California, while the Southwest experienced severe flooding. While it was wet in the south, extremely dry conditions were seen in October from central California northward into the PNW.
- Wetter than normal conditions in the Southwest in October have lowered drought concerns there, while dry conditions in the PNW have kept drought concerns in place. The current seasonal outlook is pointing to California, the Southwest, and Southern Rockies seeing drought conditions lowered or removed altogether, while the inland PNW and Northern Rockies are forecast to remain dry.
- Seasonal temperatures south, cooler temperatures north to start the month. Some rain in the western portions of the PNW this week, with more substantial precipitation events likely coming mid-month from a vigorous jet stream that will likely bring rain from the Canadian border south to the Bay Area.
- The November forecast is pointing to the northern portions of the country having a high probability of above average temperatures. The precipitation outlook is calling for continued subtropical flow into the Southwest with above average amounts across the South. West Coast states are forecast to be mild and wet for the month.
- El Niño has already brought impacts to the west and continues to strengthen, with a strong-to-very strong event likely through January-March 2027. There is increasing evidence that these impacts will likely be enhanced, but slow to develop, being more prominent in January through March, and/or spatially not what we expect.
*Note that all references to normal or averages in this report are to the 1991-2020 climate normal for each weather/climate parameter unless stated otherwise. See this website for more information on climate normals.
For a PDF of this report, click here.
Past Month and Year to Date:
October turned mild for most of the western US during the first three weeks of the month, then became cooler toward the end. Temperatures were 0.5-3.5 degrees above average for the majority of Oregon, Washington, and California, while the Rockies and Plains were 4-8 degrees warmer than average (Figure 1). Daytime maximum temperatures were much higher than average during October, while minimum temperatures were near average for the month. A warmer than average month was also experienced over most of the rest of the country, with the Plains, Mississippi River Valley, and the Great Lakes the warmest at 7-12 degrees above average (not shown). Northern New England was the only portion of the country to experience below average temperatures in October.
October precipitation in the West was dominated by subtropical moisture flowing into central to southern California and the Southwest, where much coastal and inland flooding occurred (Figure 1). Much of the Southwest received over 300% of normal precipitation for the month, with some additional rains from tropical cyclones recurving onto Mexico and moving into the Rockies, Plains, and Texas. On the other hand, an extremely dry month was seen from the Bay Area, northward into Oregon, Washington, and western Idaho and Montana, where 50% or less of normal precipitation was seen. The severe weather and heavy rains across the Corn Belt and into the Ohio River Valley seen in September slowed in October, bringing much drier conditions in these regions (not shown). The Southeast was very wet for the month, especially in Florida, where late-month precipitation events were particularly severe.
Figure 1 – Western US October 2026 temperature departure from normal (left) and percent of normal precipitation (right; images from WestWide Drought Tracker, Western Region Climate Center; University of Idaho).
The first ten months of the year have been largely warmer than normal over the Western US (Figure 1). The warmest regions remain the southwest, portions of the Great Basin, and most of the Rockies, with temperatures 4-8 degrees warmer than average. Warmer conditions have also been seen in California, with temperatures 1-2 degrees above average in the northern portion of the state and 2-4 degrees above average in the southern portion of the state. Oregon and Washington have experienced temperatures year-to-date that are running 1-2 degrees above average. The rest of the country has seen warmer-than-average temperatures since the first of the year, running 5-7 degrees above average in Texas and the Plains, and 2-4 degrees warmer than average in the Mississippi River Valley to the Great Lakes. The Southeast and eastern seaboard have experienced closer to average year to date conditions (0.5-2 degrees; not shown).
October brought enough precipitation to alter year to date totals in the Southwest but left other regions of the western US staying mostly drier than normal (Figure 2). Portions of the Great Basin and the central and northern Rockies have also seen a drier year so far, while the Four Corners region is now at 150 to over 300% of normal precipitation year to date due to an active subtropical flow. The year to date period has also seen drier than average conditions in the central to northern Plains, the Southeast, and portions of Florida (not shown), while areas of central Texas, the Gulf Coast, the Corn Belt, the Ohio River valley, and the Great Lakes have experienced roughly 150-300% of average precipitation.
Figure 2 – Western US year to date (January through October 2026) temperature departure from normal (left) and percent of normal precipitation (right; images from WestWide Drought Tracker, Western Region Climate Center; University of Idaho).
Heat Accumulation:
As the growing season ends, we can now look at final growing degree-day (GDD) departures and totals across the western US. March through October heat accumulation departures show that the vast majority of the western US ended the vintage above the 1991-2020 climate normals (Figure 3; left image). Averaged over the entire western US, growing degree-days ended roughly 5-20% above average. Average to below average locations include coastal zones in California, Oregon, southeastern Washington, and scattered valleys and mountainous areas. Lower heat accumulation can be attributed to lower maximum temperatures for many regions during 2026. Total growing degree-day amounts for the western US show the expected pattern of higher accumulation in the warmer regions of the Central Valley and southern portions of California and regions in the southwest. GDDs range from 4500 to 6000 or more from March through October (Figure 3; right image). Intermediate GDD accumulations between 2500 to 4000 occurred in the western valleys of Oregon, eastern Washington and Oregon regions, and the Snake River Valley of Idaho. Portions of the Willamette Valley and Puget Sound and valley extensions in many regions saw GDD values between 2000 to 2500.
Examining the end of season growing degree days for stations in the four main wine regions in Oregon in Figure 4 reveals the average to relatively warm growing season, with the Willamette, Walla Walla, Umpqua, and Rogue valleys seeing GDD 10-26% above the 1981-2010 climate normals and 5-15% above the 1991-2020 climate normals, or right at the average for Milton-Freewater (Figure 4). These locations ended up 1-3% higher than the average over the last 15 years. Compared to the 2025 vintage, 2026 GDDs at these four locations ended up 3-9% lower (in order of % above, McMinnville, Medford, Milton-Freewater, and Roseburg).
Figure 3 – Western US March through October 2026 growing degree-day departures from the 1991-2020 climate normal (left panel) and total growing degree-days summed during the same time period (right panel) (images from Climate Impacts Research Consortium, University of Idaho). Note that in the right panel, areas with GDD less than 2000 or greater than 6000 are not shown.
Figure 4 – Cumulative growing degree-days (base 50°F, no upper cut-off) for McMinnville, Roseburg, Milton-Freewater, and Medford, Oregon. Comparisons between the current year (2026) and a recent cool year (2010), a recent warm year (2015), and both the 1981-2010 and 1991-2020 climate normals are shown (NCDC preliminary daily data).
Drought Watch:
Moderate precipitation amounts during October; however, the overall drought footprint for the contiguous 48 states dropped only slightly to 73%, with the most extreme drought categories also dropping slightly to nearly 27% (Figure 5). The western US saw the drought footprint drop nearly 8% to just below 80%, with the most extreme categories dropping 15% to nearly 26% of the west. During October, California was wetter than average south with drier than average conditions in the central to northern portions of the state (Figure 1). However, the overall drought footprint in California remained at just over 72% experiencing some level of drought, but none of the state is currently in the more extreme categories of drought. The PNW was mostly drier than average in October, increasing drought concerns. Oregon’s drought footprint remained close to 99% of the state, with the extreme drought categories (severe, extreme, and exceptional) also remaining at roughly 58%. Drought area remained the same in Washington over the last 30 days, with 94% of the state in some level of drought and the most extreme categories of drought dropping 1% to 24%. Montana saw its overall drought footprint drop from 61% to 37%, with the extreme categories also dropping to just over 11% of the state. Idaho did not benefit from October rains as much as Montana, with the overall drought footprint dropping slightly from 86% to 84%, while the most extreme drought categories dropped 5% to under 48% of the state (Figure 5).
The anticipated start of the rainy season in the West is reflected in the 90-day drought outlook (Figure 5; right panel). Both westerly flow off the Pacific and subtropical flow into the Southwest will likely lower drought concerns for much of the West, Southwest, and Southern Plains, where improvement or removal from drought categories is likely. For the inland PNW and Northern Rockies, drought conditions are forecast to continue or develop further over the next three months. Portions of the Northern Plains across to the western Great Lakes are forecast to remain in drought, while Northern New England and the mid-Atlantic are forecast to improve or become drought-free (Figure 5; right panel).
Figure 5 – Current US Drought Monitor and seasonal drought outlook.
ENSO Watch:
Sea surface temperatures in the tropical Pacific are now nearly 3.5°C above average in the core eastern Pacific region (Figure 6). The SSTs are now at record levels, with temperatures with depth in the ocean indicating there is likely more warming of surface waters to come. Atmospheric conditions also continue to be consistent with El Niño, producing numerous eastern Pacific tropical systems, enhancing the subtropical jet stream with significant monsoon flow into the Southwest, and keeping Atlantic and Gulf hurricane activity suppressed. There have been little changes to the forecast models from numerous agencies, including the Climate Prediction Center, which all continue to call for a strengthening of El Niño at the end of the year and into early 2027. For the Northern Hemisphere winter, the outlook has a greater than 83% chance that the event will be a strong-to-very strong event. However, as mentioned here previously, El Niño-related impacts around the world are likely to be enhanced but are not guaranteed. There is increasing evidence that these impacts will likely be slow to develop, being more prominent in January through March, and/or spatially not what we expect. However, the 90-day forecast (see below) continues to show a warmer PNW and northern tier of states and a wetter California and southern tier of states, just less so than previous seasonal forecasts.
Figure 6 – Global sea surface temperatures (°C) for the period ending November 1, 2026 (image from Tropicaltibits.com).
North Pacific Watch:
The Pacific Decadal Oscillation (PDO) is currently in a prolonged negative (cool) phase; however, the September and October 2026 index values have dropped moderately. This is due to the Gulf of Alaska and western US coastal waters warming over the last 60 days. There are still portions of the horseshoe-shaped area of cooler SSTs from the Gulf of Alaska along the coast of western North America and southward to Hawaii, which contributes most to the Pacific Decadal Oscillation (PDO), but the extent and magnitude is much lower than in past months (Figure 6). The North Pacific and Tropical Pacific are currently more ‘in phase’, which historically has brought more likely weather impacts over North America from a split jet stream. In most instances where the PDO and ENSO are in phase, the PNW experiences a drier and warmer fall/winter, while most of California and the southern tier of states see much higher precipitation amounts.
Forecast Periods:
Next 5 Days: Cool and cloudy from Central California northward into Canada. Cool and clear from Southern California, into the Great Basin and the Southwest. A front approaches the PNW with moderate rain in Canada and Washington, with lighter amounts southward. Southern California and the Southwest get a reprieve from rain for a few days.
6-10 Day (valid November 8-12): A warm-up to seasonal or slightly above seasonal temperatures for most of the West. Most of the country is forecast for warmer temperatures during this period, except the Southwest where cloudiness is likely to keep conditions on the cool side. A robust northerly jet stream will likely usher in a few precipitation events, with most of the moisture coming into the Bay Area northward into the PNW. Inland and southerly areas are likely to stay on the dry side. The majority of the rest of the country is forecast to see little, if any, precipitation.
8-14 Day (valid November 10-16): Seasonal to warmer than average over the vast majority of the country with the greatest probabilities in the central to northern Plains. The northerly jet stream remains active over the Pacific and North America, with above average precipitation likely into mid-month over the West Coast and extending into the Basin and Rockies. The eastern half of the country is forecast to see near normal to below normal precipitation during this period.
30 Day (valid November 1-31): The northern tier of states is forecast to see above average temperatures, while the Southwest to Texas are where equal chances of below, near, or above-normal temperatures are likely due to a more variable temperature pattern in November (Figure 7). The greatest chance for warmer than average temperatures is forecast for the northern Plains and western Great Lakes, while the probabilities are lower for a warmer month in portions of California. The November precipitation outlook has much of the US likely seeing near average amounts during the month (Figure 7). Above average precipitation is most likely in the Southwest where subtropical flow continues to bring rain to the region, while the inland areas of the PNW and Northern Rockies will likely remain dry.
90 Day (valid November-December-January): The seasonal forecast continues to be influenced by the expected effects of El Niño; however, the 90 day outlook has backed off slightly. Not sure why, as the dynamics are still in place for a robust winter season across the West. One effect that remains consistent is that warmer than average temperatures are forecast for most of the northern portion of the country (Figure 7). Equal chances of below, near, or above-normal temperatures are forecast for the Southwest, Texas, and Southern Plains, where a more variable temperature pattern is expected over the next 90 days. The 90 day precipitation forecast is largely pointing to equal chances of below average, near, or above average over portions of the middle to northern latitudes of the US; however, there is high confidence in below average amounts in the northern Rockies and Great Lakes, while the subtropical jet stream is forecast to bring higher than average precipitation amounts to southern states from the Southwest, across the Southern Plains, the Gulf Coast, Southeast, and into the mid-Atlantic (Figure 7).
Figure 7 – Temperature (left panel) and precipitation (right panel) outlooks for the month of November (top panel) and November, December, and January (bottom panel) (Climate Prediction Center, climate.gov).