The campaign features a bottle of Pimm’s along with a jug of the drink ready to be served, alongside the caption, "Best served with sunglasses." The local temperature is also shown.
When the local temperature hits 21 degrees during peak commuter times the ad will appear and show the variations in temperature for the rest of the period.
The work will run for ten days across 12 Ocean Outdoor screens in London and Birmingham between 12pm and 4pm on Thursdays and Fridays, and between 4pm and 8pm at the weekend. It was planned by Carat and Posterscope.
Joanna Segesser, a senior brand manager for Pimm’s at Diageo, said: "Pimm’s is known by consumers as being the iconic drink of the Great British summer and consumer research has shown us that our media is not only more effective but also more efficient if it is linked to sunny weather.
"We are therefore really excited that for the first time digital out of home technology is allowing us to target consumers at just the right temperature when we know they are most responsive to our messaging."