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BackEntry title:

Cold health alert risk score

Last updated on Thursday, 8 May 2025 at 03:09pm

Summary

Topic
Cold-alert
Category
headline
API name
cold-alert_headline_matrixNumber

Rationale

Weather health alerts provide early warning when adverse temperatures may affect people's health and wellbeing.

Definition

The cold health risk score is a number between 1 and 16, determined based on the potential impact level of the low temperatures and the likelihood of those impacts occurring. This ranges from very low impact and very low likelihood up to high impact and high likelihood.

Methodology

Cold health alerts are issued when the weather conditions have the potential to impact the health and wellbeing of the population.

The alerts are given a colour (yellow, amber or red) based on the combination of the impact the weather conditions could have, and the likelihood of those impacts being realised.

These assessments are made in conjunction with the Met Office when adverse weather conditions are indicated within the forecast.

Yellow and amber alert assessments cover a range of potential impacts (including impacts on specific vulnerable groups (for example, people sleeping rough) through to wider impacts on the general population) as well as the likelihood (low to high) of those impacts occurring. This additional information should aid making decisions about the appropriate level of response during an alert period.

Once the decision is made to issue an alert (yellow, amber or red), these are cascaded to those registered to receive the alerts and made available at Weather-Health alerting system.

The cold-health alerting season operates from 1 November to 31 March. A cold-health alert may still be issued out of season if adverse weather is expected outside of this period.

Caveats

Unlike heat, there is currently no extreme cold weather warning issued as part of the National Severe Weather Warning Service (NSWWS) by the Met Office. However, warnings can be issued by the Met Office for a range of high impact weather events, including rain, fog, wind, thunderstorms and, potentially of most relevance to cold health alerts, snow and ice.

While NSWWS does not consider cold temperature explicitly, these warnings can provide information at a more specific geographical level about snow or ice forecasts and provide a holistic view of the weather picture over an alerting period that the public and emergency planners may find useful.

As with heat, situational awareness is supported through regular updates between UKHSA and the Met Office throughout the winter season. This ensures the earliest possible issuing of cold health alerts and the maximum possible warning time. Specific NSWWS warnings can also serve as contributing factors to the level of alert being issued.

Data source

Weather forecasts are provided by the Met Office. Cold-health risk scores are determined by the UKHSA Extreme Events and Health Protection Team.

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