Alert levels

Cold Alert forecasting and supporting information

This service uses information from the national cold weather health watch system which is issued to public authorities and health professionals in Sussex by the Met Office.

The forecasts are supported by information provided by the UK Health Security Agency’s Cold Weather Plan for England. The plan describes the cold weather watch system which operates in England from 1 November to 31 March annually. During this period the Met Office may forecast severe cold weather

The Cold weather health watch comprises five levels of response based on cold weather thresholds. The thresholds have been developed to trigger an alert when severe cold weather is likely to significantly affect people’s health. The alerts take account of temperature along with other winter weather threats such as ice and snow.


UKHSA Adverse Weather and Health Plan:

This is in force from 1 November to 31 March and indicates that actions should be taking place to protect health from cold weather, and that preparations should be in place to ensure service continuity in the event of severe winter weather. No warning is required unless the situation worsens to warrant an Amber alert.


Severe winter weather is forecast. Mean temperature of 2°C or less for a period of at least 48 hours and or widespread ice and heavy snow are predicted, with 60% confidence.

Response to severe winter weather. Severe winter weather is now occurring, mean temperature of 2°C or less have been reached and/or widespread ice and heavy snow.

Central Government will declare a Red alert (emergency response) in the event of severe or prolonged cold weather affecting sectors other than health.