The outlook for Thursday, Friday and into the weekend is slighter fresher and cooler but mainly dry and bright, with some rain expected on Saturday.
"Night-time temperatures will remain warm and humid for many areas making sleeping conditions hard for some".
Parts of the region could be hit by torrential downpours, thunder and lightning and even hail tomorrow afternoon, the Met Office said.
Power supplies could also be disrupted by frequent lightning associated with the heaviest rain.
They have said we need to prepare for the rain to be heavy and thundery at times in the early hours of Wednesday.
"This could result in some disruption, more likely from late Wednesday afternoon, which may include sudden localised flooding of transport routes, homes and businesses".
The Met Office forecast for Monday for Hull and East Yorkshire says: "Another hot day with good spells of sunshine, although perhaps a little more in the way of cloud developing through the day".
Dr Thomas Waite from Public Health England said: "Much of the advice on beating the heat is common sense and for most people there's nothing to really worry about". However, some groups can be particularly vulnerable and at much greater risk of harm, especially older people, babies and young children.
Britain is in the middle of what is set to be the longest heatwave in 20 years - and it's showing no signs of slowing down any time soon.
With the hot weather also comes a warning of a very high pollen count and high UV levels this week.