Forecasts cited in the latest update point to highs near 100F in Dallas on 13 June, with Houston also expected to push into the upper 90s around the same point in the week.
That is the key point. Tournament football is not only played in stadiums. It is experienced on trains, in car parks, outside fan zones and in long entry lines.
There is at least one obvious layer of protection. The report says matches in Dallas are being staged at AT&T Stadium, which is air-conditioned, while Houston games are at NRG Stadium, set to operate as Reliant Stadium during the tournament.
That helps once supporters are inside. It does not remove the bigger logistical challenge:
This is why heat management is not a side issue for a World Cup in North America. It is part of the event design. Water access, shaded waiting areas, medical visibility and clear travel advice can shape the experience as much as the football itself.
The next thing to watch is simple: whether the forecast holds as matchday approaches, and how host-city organisers respond if the temperatures in Dallas and Houston stay near those projected levels.