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Project analysis

Unfortunately, there are times when exceptionally adverse weather conditions on site delay project completion. ‘Force majeure’ (or superior force) events are beyond the control contracting parties, and the Met Office offer a range of trusted reports to help you resolve contractual claims.

We have combined our historic gridded database of long-term average values with a database of present observations, to create our location-based reports. 

Download our Project Analysis Catalogue

A practical catalogue to inform project analysis and downtime claims. Use accurate, trusted data to evaluate the risk of rainfall, wind speed, snowfall and temperature. 

To enquire or make an order from our range of construction reports below, call our 24-hour customer centre 0370 900 0100 or email

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Monthly downtime summaries

Monthly downtime summary reports provide you with detailed weather conditions experienced at your months of interest. These conditions can be compared to their corresponding long-term averages and 1-in-10 year values identifying weather conditions that fall outside of normal parameters which could not have been planned for.

Our downtime summary reports are suitable for guiding a range of construction contracts. When you are looking to make a claim for downtime and/or an extension of time (EoT), we produce reports suitable for:

NEC3 & 4 Engineering and Construction Contract: Clause 60.1 (13)
JCT Standard: Clause 2.29.8 or 2.29.9
JCT Design & Build (D&B): Clause 2.26.8
JCT Intermediate: Clause 2.20.8
FIDIC Yellow Book: Clause 8.5(c)

Location based monthly downtime summaries

Location based downtime summaries use weather data from more than 3,600 locations across the UK. They include up to 16 weather parameters (11 parameters with LTAs and 1-in-10 year values):

Monthly Rainfall Total (mm) 0900-0900
Total Days of Rain > 5mm 

Monthly Snowfall Total (cm)
Total Days of Snow
Total Days with Snow Lying at 0900
Maximum Snow Depth (cm) at 0900

Minimum monthly Air Temperature (°C)
Minimum monthly Ground Temperature (°C)
Total Days of Air Frost
Total Days of Ground Frost
Total Days of Freezing - day max temp ≤ 0°C

Monthly Sunshine Total (hours)
Monthly Solar Radiation Total (kWh/m^2)

Mean monthly Wind Speed (mph) 0900-0900
Maximum monthly Gust Speed (mph) 0900-0900

Total Days of Lightning









'With solid statistical evidence derived from Met Office observations both parties can agree on whether a particular month contains a compensation event' - NEC.

Our system has been rigorously tested to ensure robustness and accuracy. Read our in depth technical report on how the testing was conducted.

Station based monthly downtime summaries

Using weather data from 100 weather stations across the UK there are three different reports available:

Bulk buy offers - Save when subscribing to multiple reports, simply ask us at

If you require weather monitoring and alerting, it may be worth considering our range of Forecast Services which provide location-specific and timely alerting to the weather thresholds that affects your on-site activity.

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