It’s been so hot! It will be a good idea to go to Tokyo Bay area and feel the sea breeze under this hot and humid weather. There are many spots in and around Tokyo Bay Area so it is rather difficult for me to choose where to recommend. Among various places, let me introduce you Harumi area and the vicinity today.
Harumi is the pier in Tokyo Bay area which has a cruise terminal. You can have a great view of the Bay with Rainbow Bridge. This 798-meter bridge was constructed in 1993.

Rainbow Bridge

Rainbow Bridge viewing from Fujimi Bridge in Ariake
I found a fantastic panorama photo in Wikipedia:
By Javachan – Shot by Wikipedia user javachan
Transferred from English Wikipedia; en:File:Rainbow Bridge,Tokoyo Bay from Odaiba.jpg
Transfered by Gobonobo, CC BY-SA 3.0, Link
The night view of Rainbow Bridge is also stunningly beautiful.
Sometimes, unique ships come to the pier. I once saw a tall ship came all the way from Spain.
There are several bridges over the Sumida River which float into Tokyo Bay. Many of them have elegant shapes and it is fascinating to walk along the street looking at those beautiful bridges.
One of the bridges I like is Chuo-Ohashi Bridge which stands near from the mouth of the Sumida River. It is 210 meter long and was constructed in the same year as Rainbow Bridge in 1993.

Chuo-Ohashi Bridge
By Stevec240 (talk) (Uploads) – Own work, CC BY-SA 3.0, Link
This Chuo-Ohashi Bridge connects the north side of Tsukuda Island and the north-eastern shore. Tsukuda is a small island in the mouth of the Sumida River. The island is surrounded by the river-front skyscrapers but there is an traditional streetscape inside the island. This area is the origin of tsukudani which is traditional preserved food which is made by simmering fish in dash soup with soy source. There are several old tsukudani shops in the island and when you walk on the streets, you can smell the nice savoury aroma of sweet salty soy source.
For More Information on Tokyo Bay Area (Harumi & Tsukuda)
<Harumi>
Address of Harumi Passenger Terminal: 7-1 Harumi 5-chome, Chuo-ku, Tokyo
Access: 15-min taxi ride from Ginza or 20-min bus ride from Ginza. For more details, please check the website of the Terminal.
<Chuo-Ohashi Bridge>
Address: Tsukuda 1-chome, Chuo-ku, Tokyo
Access: several-minute walk from Tsukishima or Hatchobori Station of Tokyo Metro
It is about 40-minute walk between Harumi Passenger Terminal and Chuo-Ohashi Bridge. You can enjoy the landscape of Tokyo Bay Area.