England face heat test against Norway in Miami quarter-final

England head into unknown territory at this World Cup when they face Norway in Miami on Saturday, playing in searing temperatures that could approach the threshold considered dangerous by the global players' union. The Three Lions have been largely shielded from excess heat in North America, with their schedule including indoor matches in Dallas and Atlanta, and outdoor games in Boston, New Jersey and Mexico City that were played in cooler, damper conditions.

That changes on Saturday for their quarter-final tie (kick-off 22:00 BST), which could be played in conditions close to what the global players' union Fifpro considers too dangerous for the game to go ahead. Norway, by contrast, have played all but one of their matches outdoors, the exception being their last-32 victory over Ivory Coast in the air-conditioned Dallas Stadium. Their 2-1 victory over Brazil on Sunday was played outside while New Jersey was under a US National Weather Service (NWS) extreme heat warning.

Weather forecast: hot and humid

Conditions in Miami will be hot and humid. While air temperatures are likely to sit about 33C (91F), once humidity is added, it will feel like about 41C (106F). The National Weather Service has issued a heat advisory for the area on Saturday, warning that high temperatures and humidity may cause heat-related illnesses. It advises people to drink plenty of fluids, stay in an air-conditioned room and stay out of the sun.

Alongside the high temperatures, there is a risk of thunderstorms, especially near the start of the match, and a possibility of showers. Otherwise, sunny spells are expected. The Wet Bulb Globe Temperature (WGBT) will also sit around 27C. The WGBT is an index that combines air temperature, humidity and surface temperature readings and is used by global sporting bodies such as Fifa to help keep players safe. In its guidelines for playing in heat, players' union Fifpro says a WBGT above 28C should lead to the "delay or postponement of matches" until conditions are safer. However, there is no suggestion that the game will not take place.

Temperature exposure: England vs Norway

While two of England's group-stage matches were played in the hotter Texas and Georgia climates, they felt the benefit of air-conditioned stadiums, where the temperature is set to a comfortable 21C. The warmest the Three Lions have played in was 25C for the final group game against Panama, but that featured overcast skies. July is Mexico City's wettest month of the year, so when England headed to altitude last Sunday they would have felt at home — 18C and rain. The hot and humid weather in Miami will be a very different challenge.

Norway's tournament opener against Iraq, meanwhile, was played under clear skies and in a temperature of 25C. There was rain and cloud during their games against Senegal and France, though they rested most of their first-choice players against Les Bleus. After being indoors against Ivory Coast, Norway experienced oppressive conditions in the victory over Brazil. The temperature in New Jersey hit 31C in the shade, but on the pitch the heat and humidity would have made it feel far hotter.

England's preparation for the heat

England's initial base when arriving in the United States was, coincidentally, Florida. Thomas Tuchel and his team spent 10 days in the area, playing warm-up games against New Zealand in Tampa and Costa Rica in Orlando. The Three Lions then moved to their tournament facility in Kansas, where daily air temperatures are about 32-34C (90-93F). That should help England cope with the heat.

Dr Lee Taylor from Loughborough University — a leading expert in elite athlete performance and the challenges of heat and altitude — told BBC Sport acclimatisation was crucial. "That is the gold-standard method to protect players' health and performance," said Taylor.