Delaware Climate – June 2026 Update
Top 5 Cities: Wilmington, Dover, Newark, Middletown, and Smyrna
This month in numbers
Delaware experienced its 5th warmest June on record, with an average temperature of 23.61°C, a significant 2°C above the 1961–1990 baseline. Maximum temperatures were particularly notable, ranking as the 3rd highest for June at 30.06°C, which is 2.5°C above average. Globally, June 2026 was the 3rd warmest June for land temperatures on record.
What changed
The April–June 2026 period saw Delaware record its 6th warmest average temperature and 5th warmest maximum temperature in 77 years of records, both approximately 2°C above the 1961–1990 baseline. This trend aligns with a broader pattern, as global land temperatures for the same three-month period ranked as the 2nd warmest on record. Delaware's 1-month anomaly of +2.00°C places it as the 66th warmest out of 234 regions globally, and the 2nd warmest within the NOAA Northeast US climate region for June.
What’s driving change?
The elevated temperatures in Delaware are consistent with the broader trend of land warming faster than ocean. The region also experienced a notable concentration of wildfire activity, with four events occurring between late June and early July, representing 100% of the annual total for Delaware. Additionally, a flash flood warning was issued for southeastern Kent County and north-central Sussex County on July 6, with heavy thunderstorms causing 1.5 to 3 inches of rain to fall in a short period, leading to flash flooding.
Looking ahead
The NOAA Climate Prediction Center's seasonal outlook for July-August-September 2026 suggests a continued likelihood of above-normal temperatures for Delaware.
Sources:
Generated by Gemini from climate data and web sources
At a Glance
Temperature – Average
Climate Map – USA
Source: NOAA Climate at a Glance — US states & climate regions (tavg, pcp). Anomalies are vs the 1961–1990 baseline (temperature) or 1991–2020 (rainfall). See methodology.
Year-on-Year Trends
The 4byo Climate Helix – Delaware
Data: NOAA National Centers for Environmental Information. Baseline: first 30 yrs on record. Recent: last 10 yrs on record.
Delaware – Monthly Temperature – All Years
Data: NOAA National Centers for Environmental Information. Baseline: first 30 yrs on record. Recent: last 10 yrs on record.
Records – Delaware
NOAA National Centers for Environmental Information - Anomalies vs 1901-2000 mean
Shifting Seasons
Warm / cold seasonsKöppen Cfa · TemperateHow spring and autumn have shifted in Delaware. Spring is defined as the date monthly temperatures first rise above the long-term annual mean (12.3°C, from 1950–1979); autumn is the date they fall back below it. Temperature swings 23.6°C peak-to-peak across the year - a classic four-seasons rhythm.
Baseline vs recent monthly temperature climatology. Biggest warming: Feb (+3.3°C).
Data: NOAA National Centers for Environmental Information. Baseline: first 30 yrs on record. Recent: last 10 yrs on record.
Rainfall & Precipitation
Rainfall & Rain Days – Totals
Emissions & Energy
Explore
Explore Climate Data
Data Sources
Data Sources for Delaware
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.
FAQs
FAQs
How is the climate in Delaware changing?
Delaware 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 Delaware come from?
Climate data for Delaware 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 Delaware climate data cover?
The Delaware climate profile covers Wilmington, Dover, Newark, Middletown and surrounding areas. Delaware climate data from NOAA Climate at a Glance
How often is the Delaware climate update refreshed?
The Delaware 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.