US Upper Midwest Climate – July 2026 Update
Top States: Michigan, Minnesota, Wisconsin, and Iowa
Summary
The US Upper Midwest experienced pronounced regional warmth during July, driven by mid-summer high-pressure ridges that elevated temperatures across the Great Lakes and northern Plains. These warm conditions reflect broader continental trends, with thermal stress building across agricultural zones and urban centres alike. Looking ahead, long-range outlooks project above-normal warmth to persist across the region through autumn.
This month in numbers
July delivered a 1-month temperature anomaly of +1.97°C above the 1961–1990 baseline for the US Upper Midwest. The region recorded a 3-month anomaly of +0.80°C and a 12-month rolling anomaly of +1.65°C, pointing to sustained warm conditions. While the Midwest did not top global monthly rankings, broader cross-region data reveals that 7 of the 10 highest 12-month rolling anomalies worldwide are US states, highlighting widespread national warming.
Hottest & coolest US states
Northern members led the regional temperature surge. Minnesota (US Minnesota) was the warmest state in the group with a monthly anomaly of +2.48°C, followed closely by Wisconsin (US Wisconsin) at +2.04°C and Michigan (US Michigan) at +2.00°C. Iowa (US Iowa) recorded the mildest anomaly in the regional group at +1.28°C, though conditions there still remained well above historical baselines.
What's driving change?
Mid-summer high-pressure systems created that trapped hot air over the central continent. This regional trend is reinforced by Seasonal shifts that bring warmer summer conditions to northern latitudes. Active weather hazards were also recorded. All of US Upper Midwest's 2 tropical cyclones this year have happened in the past month. Separately, all of US Upper Midwest's 2 wildfires this year have happened in the past month. Live hazard tracking across the region is available at Extreme Weather tracker.
Looking ahead
NOAA seasonal outlooks favour above-average temperatures across the upper Midwest through late autumn as El Niño strengthens in the tropical Pacific.
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.
Long-Term Trends
Combined Timeline – US Upper Midwest
Precipitation, Sunshine, Frost and Snow are converted to standard deviations from their own average so they can share an axis with Temperature.
NOAA Climate at a Glance - regional tavg / pcp
Heatwave Days – US Upper Midwest
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), aggregated by 4BYO across member states. Refreshed roughly 1-2x/year, ~7-8 months behind present.
Hottest & Coolest in US Upper Midwest this Month
1-month anomaly vs 1961–1990 across the 4 members we cover. Click a name to open its profile.
Year-on-Year Trends
The 4byo Climate Helix – US Upper Midwest
NOAA Climate at a Glance — regional tavg / pcp (monthly absolutes).
Monthly Temperature – US Upper Midwest
Background lines show the last 40 years (plus the record year and its opposite, wherever they fall).
NOAA Climate at a Glance — regional tavg / pcp (monthly absolutes).
Records – US Upper Midwest
NOAA Climate at a Glance - regional tavg / pcp - Anomalies vs 1901-2000 mean
Shifting Seasons
Warm / cold seasonsHow spring and autumn have shifted in US Upper Midwest. Spring is defined as the date monthly temperatures first rise above the long-term annual mean (6.0°C, from 1950–1979); autumn is the date they fall back below it. Temperature swings 32.3°C peak-to-peak across the year - a classic four-seasons rhythm.
Baseline vs recent monthly temperature climatology. Biggest warming: Jan (+3.4°C).
NOAA Climate at a Glance — regional tavg. Baseline: first 30 yrs on record. Recent: last 10 yrs on record.
Emissions & Energy
Explore
Explore Climate Data
Data Sources
Data Sources for US Upper Midwest
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.
US 9-region temperature and precipitation series (1895–present).
US state-level CO₂ emissions and electricity generation mix by fuel source. Energy Information Administration.
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 US Upper Midwest changing?
US Upper Midwest 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.
Where does the climate data for US Upper Midwest come from?
Climate data for US Upper Midwest comes from authoritative climate datasets including national meteorological services and peer-reviewed reanalyses, 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 US Upper Midwest climate data cover?
The US Upper Midwest climate profile covers Michigan, Minnesota, Wisconsin, Iowa and surrounding areas. NOAA Upper Midwest - IA, MI, MN, WI
How often is the US Upper Midwest climate update refreshed?
The US Upper Midwest 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 US Upper Midwest 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 US Upper Midwest 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.