What is the lower temperature for a concrete pour?

Five degrees is a common planning figure and the default here; below it concrete gains strength too slowly without measures. Your concrete specification and supplier set the figure for your pour.

Does it cover the night after the pour?

The limits read the next 24 hours from now, which covers the night after a pour today. The 10 day outlook shows each day’s low for pours later in the week.

Can I have a warning the day before?

Turn on limit alerts for the site and a message arrives when the pour window is forecast to be exceeded, or have the 07:00 brief each morning.

Weather Metric › Concrete pour weather

When is the temperature outside your 5 to 30 degree pour window?

Put in the site and Weather Metric reads the next 24 hours against your pour window and your rain threshold, and shows the lowest and highest temperatures and when they come.

The pour window

The pour preset starts the window at 5 and 30 degrees: below the lower figure concrete gains strength too slowly, and above the upper one it goes off before it is placed. They are common planning figures, not a specification; set yours from the concrete specification and the supplier.

The window is one limit with two edges, and the first screen says which edge the forecast comes closest to and when.

Approached, not only exceeded

A temperature within 2 degrees of either edge is shown as Approached, so a pour planned for early morning on a cold day shows up before the window is crossed. Where it is exceeded, the caution line suggests considering rescheduling the pour or agreeing cold or hot weather measures with the supplier.

Rain and the nights after

Rain on a fresh pour is read against the pour preset’s threshold of 2 mm an hour. The 10 day outlook on the Now screen gives each day’s low, so a frost after a pour can be seen coming. Mortar has its own minimum, 2 degrees by default, for brickwork on the same site.

What it leaves to you

Weather Metric reports forecast and measured conditions against limits you set. It does not decide whether an activity goes ahead: the lift plan, the method statement, the manufacturer’s figures and the people responsible on site do that.

Questions people ask

What is the lower temperature for a concrete pour?: Five degrees is a common planning figure and the default here; below it concrete gains strength too slowly without measures. Your concrete specification and supplier set the figure for your pour.
Does it cover the night after the pour?: The limits read the next 24 hours from now, which covers the night after a pour today. The 10 day outlook shows each day’s low for pours later in the week.
Can I have a warning the day before?: Turn on limit alerts for the site and a message arrives when the pour window is forecast to be exceeded, or have the 07:00 brief each morning.