I think it would look like Venus. At near boiling, most of the atmosphere is going to be water vapour. With a higher gravity you will get a much thicker atmosphere, especially without a moon to create tides in the atmosphere.
The amount of water vapour air can hold increases about 7% per degree C at Earthly temp/and pressure. (20 C) This rapid increase is one reason why the equator didn't cook in the last warm period.
You need to come up with a plausible explanation for much less atmosphere, which I suspect means a lot of research into planetary development -- a nascent science, as we don't have many examples with historical data.
I expect two circulations happening: The top of the atmosphere will be powered by the star, and the lower limit of it will be the lower limit of solar penetration. The air will be fairly dry -- the lower atmosphere will act as a water sink. Circulation here will be fast. You have only dry air, so air is the only transport mechanism between the equator and the pole. There will be a shortage of nucleation centers (no dust...) so cloud formation will be delayed, then abrupt.
Below that the heat is from residual radioactivity and leftover scraps of geology. This is a small source of heat so you will get slow circulation toward the poles. While there is lots of water vapour in this air, there is no real reason for it to mix with the upper atmosphere. When precip in the upper atmosphere happens it will drop into the lower atmosphere and be trapped there.
Because of the much higher density of the atmosphere, 100 C will be far below boiling point.
The surface will be dark, stirred by an occasional puff of wind as a parcel of water vapour lifts free of the surface and makes a lazy climb upward.
Volcanoes would be a source of updrafts, but most of the surface will be very uniform in temperature (crustal heat leaks equally everywhere)
You may have a candidate for the world's most boring planet contest. (grin)