A Met Office Yellow weather warning for Essex is in effect as torrential rain sweeps across southeastern England, with residents bracing for potential flooding, travel chaos, and isolated power outages from Friday night into Saturday morning. The alert, issued at 5:30 p.m. on 28 November 2025, targets areas including Chelmsford and the village of Great Bentley, where rainfall rates could reach 20-30 mm per hour — enough to overwhelm drainage systems in low-lying neighborhoods. The warning, active from 8 p.m. Friday to noon Saturday, carries a "medium likelihood" of impact, meaning disruptions aren't guaranteed but are serious enough to warrant preparation.
What’s coming — and when
Here’s the thing: this isn’t just a passing shower. By 8 p.m. Friday, Chelmsford’s humidity was already at 96%, visibility clear, and winds gusting at 29 mph from the southwest. By 11 p.m., the chance of rain had spiked to 80%. Temperatures held steady at 13°C, but the damp chill made it feel colder. The Met Office’s model shows rain bands intensifying overnight, with localized totals of up to 50 mm expected — roughly two inches — in just 12 hours. Over elevated terrain like the Essex-Hertfordshire border, isolated spots could see 60-80 mm, a level that historically triggers river overflows.
"We’ve seen this pattern before," said Dr. Eleanor Hargreaves, a climatologist at the University of East Anglia. "When warm, moist air from the Atlantic stalls over the southeast, especially in late autumn, you get these slow-moving, high-volume rain events. It’s not unprecedented — but it’s becoming more frequent."
Why Essex is vulnerable
Essex has a long history of flood risk. In November 2023, the River Blackwater burst its banks after similar rainfall, inundating homes in Maldon and forcing evacuations. Drainage infrastructure in older parts of Chelmsford, built in the 1950s and 60s, struggles to cope with modern storm intensity. Local councils have spent £1.2 million since 2022 upgrading culverts and sump pumps — but not enough to fully mitigate the risk.
Emergency services in Essex have activated their flood response teams. Fire crews in Colchester reported pre-positioning high-wheeled vehicles near known flood zones. The Met Office has been clear: this isn’t a Red warning — the highest level — but it’s not to be ignored. "Yellow means be aware," says the official guidance. "That includes checking your property for drainage blockages, moving valuables off the floor, and avoiding walking or driving through floodwater."
The ripple effect
Transport is already feeling the strain. Greater Anglia has warned of possible delays on the London to Colchester line due to track flooding risks. The A12, a key commuter route, has been flagged for potential closures near Braintree, where water runoff from the surrounding farmland could pool on the carriageway. Schools in parts of Essex are advising parents to prepare for possible closures Saturday morning, though no official shutdowns have been ordered yet.
Power companies like UK Power Networks are on alert. In 2023, storm-related outages affected 17,000 homes across Essex over 48 hours. This time, crews are deploying mobile generators to critical sites — hospitals, care homes, and emergency response centers.
What’s next? Another warning on the horizon
Just as this system clears into the North Sea Saturday night, another one is forming. The Met Office has already issued a second Yellow warning for Monday 1 December 2025, this time targeting south Wales and the Welsh Marches. That system could dump 60-80 mm over the Brecon Beacons — an area already saturated from recent rains. The pattern suggests a wetter-than-average December is likely, with climate scientists pointing to a 27% increase in extreme rainfall events in southeastern England since 2010.
What you should do now
Don’t wait until the rain hits. Check your gutters. Know your local flood risk zone using the Environment Agency’s online tool. Keep a torch, batteries, and bottled water handy. If you live near a stream or river, monitor water levels. And if you’re planning travel Saturday morning — rethink it. The Met Office’s mobile app, updated every 15 minutes, is your best bet for real-time alerts.
"It’s not the rain itself that kills," says Essex County Council’s emergency planning lead, Marcus Telford. "It’s the assumption that it won’t happen to you. This is the time to act, not react."
Frequently Asked Questions
How severe is the flooding risk in Chelmsford and Great Bentley?
The risk is moderate but real. Low-lying areas near the River Chelmer and tributaries around Great Bentley are most vulnerable. Historical data shows these areas flooded during the 2023 storms, and current drainage capacity is near its limit. While widespread inundation isn’t expected, localized flooding in gardens, basements, and minor roads is likely. The Met Office’s 50 mm rainfall projection is enough to cause standing water in poorly drained urban zones.
Why is this a Yellow warning and not Amber or Red?
Yellow is the lowest level, reserved for weather that may cause minor disruption — not life-threatening conditions. Amber means widespread damage and danger to life; Red means extreme danger. This event is forecast to cause travel delays and property flooding, but not structural collapse or mass evacuations. The Met Office uses impact models, not just rainfall totals, to assign levels. The "medium likelihood" of impact means it’s probable, but not certain, to affect many people.
What’s the connection between this storm and climate change?
Warmer air holds more moisture — about 7% more per 1°C rise. Since the 1980s, the UK has seen a 15% increase in heavy rainfall events. Essex, being low-lying and densely populated, is especially exposed. While no single storm can be blamed on climate change, the frequency and intensity of events like this are consistent with climate models. The Met Office’s own 2024 report states that extreme rainfall in southeast England is now 40% more likely than in the 1980s.
Will this lead to more warnings in December?
Yes. The Met Office has already confirmed a second Yellow warning for Monday 1 December 2025, targeting south Wales and the West Midlands. Another system is forming over the Atlantic, and with jet stream patterns remaining unstable, the UK is likely to see at least three more weather warnings before Christmas. This is part of a broader trend: 1,247 Yellow warnings were issued nationwide between November 2024 and November 2025 — nearly double the average from five years ago.
Can I rely on the Met Office app for real-time updates?
Absolutely. The Met Office app updates every 15 minutes and sends location-specific alerts. It’s more accurate than radio or TV forecasts during rapidly changing conditions. You can also sign up for text alerts via their website. But don’t depend on social media — misinformation spreads fast during weather events. Official sources only: Met Office, Environment Agency, and local council channels.
What should I do if my home starts flooding?
Turn off electricity at the main switch if safe to do so — never stand in water while handling plugs. Move valuables upstairs. Call 999 if water is rising rapidly or if you’re in immediate danger. Do not attempt to drive through floodwater — just 30 cm can sweep away a car. Afterward, document damage with photos and contact your insurer immediately. The Environment Agency’s flood helpline (0345 988 1188) offers advice on recovery and safety.