'most dry' is correct and usable in written English.
It can be used as an adjective to describe something that has very little moisture. For example, "The desert air was most dry."
Cary Grant, Hollywood's most dry and dapper gentleman, was full of secrets.
Most dry land has been picked over, and better technology allows exploration in ever deeper waters.
He started Tiecrafters because he was not satisfied with the way most dry cleaning establishments cleaned ties.
Precision is important in baking, so weigh most dry ingredients on a scale instead of measuring them in cups, which is prone to vicissitudes.
To give a little context, most dry wines usually won't exceed 200 ppm, and dried fruits can contain anywhere between 500 and 3000 ppm.
"Climate change over the 21st century is projected to reduce renewable surface water and groundwater resources significantly in most dry subtropical regions," the IPCC says.
That's the most dry-aged beef you're likely to see outside of a Chicago steakhouse, and there's more.
Ideally, the ship should be run on trial in the fully loaded condition; but this is difficult to achieve with most dry-cargo ships.
Quicker and less salty than most dried bouillons, the clear stock they produce is the very essence of the forest floor.
Spain's Los Monegros region, in Aragon, is one of the most driest parts of the country.
Extracted DNA can reliably be amplified by means of the polymerase chain reaction (PCR) and sequenced for most dried fungal specimens up to 30 years old.
