Connecticut Climate – July 2026 Update
Top 5 Cities: Bridgeport, New Haven, Stamford, Hartford, and Waterbury
Summary
Connecticut experienced an exceptionally wet month, recording its 5th wettest July in 77 years of records with 185.42 mm of precipitation. Repeated storm systems dumped nearly double the typical monthly rainfall, causing localised flash flooding and washing out roads, even as underlying moisture deficits persist in select inland areas. Globally, land temperatures reached their 3rd highest July level on record. Tropical Pacific dynamics are actively evolving, with a moderate El Niño currently in place and forecast to peak at Very Strong intensity in Sep-Nov. Warmer-than-average conditions are expected to persist across the region over the coming months.
This month in numbers
The primary storyline for the month was atmospheric moisture, as total rainfall reached 185.42 mm, representing an anomaly of +89.3 mm above the 1961–1990 baseline and securing 5th place among wettest Julys since state records began in 1950. Temperatures were also elevated but less extreme than rainfall; the monthly average temperature sat at 22.22°C, which is +0.7°C above the long-term baseline and ranks as the 29th warmest July on record. Daytime maximum temperatures averaged 28°C (+0.4°C anomaly, 38th warmest), while nighttime minimum temperatures stayed warmer at 16.39°C (+0.9°C anomaly).
What changed
Looking at the broader seasonal trend, the May–July 2026 period averaged 18.89°C (+0.9°C anomaly), making it the 20th warmest such three-month stretch on record for Connecticut. Seasonal precipitation over these three months totalled 325.12 mm (+21.6 mm anomaly), ranking 27th overall as heavy midsummer rains offset a drier late spring. Regionally, Connecticut was 0.39°C cooler than the NOAA Northeast US climate region average anomaly of +1.05°C. Globally, land temperatures for May–July 2026 ranked as the 2nd warmest on record (+1.5°C anomaly), demonstrating how local variations in storm tracks can temporarily temper land surface warming relative to broader planetary trends.
What’s driving change?
Recent atmospheric patterns across the region reflect larger climate drivers, including that stalled moisture-laden storms over the eastern seaboard and dynamics that elevate regional summer temperatures. Tropical ocean conditions are influenced by ENSO, where a moderate El Niño currently prevails with a Relative Niño Index anomaly of +0.98°C, tracked at ENSO. Historical teleconnections suggest El Niño winters in the northeastern United States lean milder roughly half the time, though the regional influence remains modest. In terms of hydrologic extremes, all of Connecticut's 1 flood this year has happened in the past month, as monitored on our live map at Extreme Weather tracker.
Looking ahead
Seasonal climate outlooks indicate an increased likelihood of above-average temperatures continuing across Connecticut over the next 1–3 months, alongside an intensifying El Niño that has a 93% probability of reaching Very Strong intensity in Sep-Nov.
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 – Connecticut
Köppen Dfa · ContinentalConnecticut has a continental climate (Köppen Dfa: Humid continental - hot summer), with distinct warm summers and cool-to-cold winters. July is typically the warmest month, averaging 23.3°C, while January is the coldest at -1.4°C. Annual precipitation averages around 1246mm, spread fairly evenly across the year.
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 – Connecticut
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 – Connecticut
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 – Connecticut
Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).
Monthly Temperature – Connecticut
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 – Connecticut
NOAA National Centers for Environmental Information (frost: World Bank CCKP; snow: GPCC (DWD)) - Anomalies vs 1901-2000 mean
Shifting Seasons
Warm / cold seasonsKöppen Dfb · ContinentalHow spring and autumn have shifted in Connecticut. Spring is defined as the date monthly temperatures first rise above the long-term annual mean (9.0°C, from 1950–1979); autumn is the date they fall back below it. Temperature swings 25.2°C peak-to-peak across the year - a classic four-seasons rhythm.
Baseline vs recent monthly temperature climatology. Biggest warming: Feb (+3.0°C).
Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).
Emissions & Energy
Explore
Explore Climate Data
Data Sources
Data Sources for Connecticut
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 Connecticut changing?
Connecticut 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 Connecticut?
Connecticut has a continental climate (Köppen Dfa: Humid continental - hot summer), with distinct warm summers and cool-to-cold winters. July is typically the warmest month, averaging 23.3°C, while January is the coldest at -1.4°C. Annual precipitation averages around 1246mm, spread fairly evenly across the year.
Where does the climate data for Connecticut come from?
Climate data for Connecticut 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 Connecticut climate data cover?
The Connecticut climate profile covers Bridgeport, New Haven, Stamford, Hartford and surrounding areas. Connecticut climate data from NOAA Climate at a Glance
How often is the Connecticut climate update refreshed?
The Connecticut 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 Connecticut 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 Connecticut 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.