CONNECTICUT — A sweltering stretch of summer weather is gripping Connecticut this week, with dangerous heat, intense humidity, and scattered severe thunderstorms dominating the forecast across the Nutmeg State.
The National Weather Service has issued a heat advisory and a hazardous weather outlook for much of the state, warning of heat index values reaching up to 100°F (38°C) over the coming days. Meteorologists stress that this oppressive heat, combined with elevated humidity, will significantly increase the risk of heat-related illness, especially during the afternoon and early evening hours.
Tuesday, July 15, is expected to be hot and humid, with temperatures peaking between 85°F and 90°F (29°C–32°C). WFSB meteorologists indicate that dew point levels will be high enough to make conditions feel like the mid-to-upper 90s. If Bradley International Airport reaches 90°F (32°C), it could mark the start of Connecticut’s second heat wave of 2025.
Forecasts highlight isolated thunderstorms possible each day this week, with the potential for strong to severe storms increasing significantly by Friday, as a cold front approaches from the west.
Forecast for southern Connecticut
Tuesday: A 30% chance of early showers and thunderstorms, mostly before 11 a.m. The day will start out cloudy, becoming mostly sunny by afternoon, with a high around 86°F (30°C). Winds turning south at 5 to 8 mph.
Tonight: Patchy fog may develop after 11 p.m. Expect partly cloudy skies, with a low near 72°F (22°C). Winds will become calm overnight.
Wednesday: A 20% chance of thunderstorms after 2 p.m. Early morning fog is likely before 9 a.m. Otherwise, mostly sunny with a high near 88°F (31°C). Heat index values could reach 99°F (37°C). Winds from the south at 5 to 8 mph.
Wednesday night: A 50% chance of thunderstorms after 8 p.m. Mostly cloudy, with a low around 73°F (23°C). Light south wind, turning calm overnight.
Thursday: A 40% chance of thunderstorms. Partly sunny, with highs close to 90°F (32°C). Winds from the south at 5 to 9 mph.
Thursday night: A 30% chance of evening thunderstorms. Partly cloudy, with a low near 75°F (24°C).
Friday: A 30% chance of late-day thunderstorms, as the cold front nears. Mostly sunny, with a high near 89°F (32°C).
Forecast for northern Connecticut
Tuesday: Sunny and hot, with only a 20% chance of isolated storms between 2 and 3 p.m. High near 90°F (32°C), with heat index values approaching 97°F (36°C). Light south breeze at 5 to 7 mph.
Tonight: Mostly clear, with some fog possible after 5 a.m.. Low near 70°F (21°C), and light south wind.
Wednesday: A slight chance of morning showers, then a 30% chance of storms after 2 p.m.. Expect mostly sunny and hot conditions, with a high near 91°F (33°C). Heat index values could hit 99°F (37°C). Winds south at 3 to 8 mph.
Wednesday night: Mostly cloudy, with a 40% chance of storms. Low around 74°F (23°C). South wind around 7 mph. Rainfall amounts could range up to a quarter inch, or more in heavier cells.
Thursday: A 50% chance of thunderstorms, under mostly cloudy and hot skies. High near 90°F (32°C), with southwest winds between 6 and 10 mph.
Thursday night: A 30% chance of storms, mostly before 9 p.m. Partly cloudy, with a low near 74°F (23°C). Winds southwest at 5 to 7 mph.
Friday: A 30% chance of late-day thunderstorms, with mostly sunny skies. High near 88°F (31°C). Winds shifting northwest at 5 to 8 mph.
Friday night: Possible early storms, ending before 7 p.m. Skies becoming partly cloudy, with a low near 64°F (18°C). Winds from the north at 6 mph.


