Weather: An easy way to set a scene is to describe the weather - is it overcast and damp with a slight hair-ruffling wind? Is the sun blazing down with scarcely a cloud in the sky? Is the night open to the vault of a million stars, or does bone chilling rain cut through the darkness?I don't know: does bone chilling rain cut through the darkness? This wouldn't be bad advice to include in the Dungeon Master's Guide but here we have a pre-packaged adventure that's supposed to be shouldering the DM gruntwork. A quick flick through the module shows that it doesn't follow its own advice even once. Despite a paragraph of read-it-straight-to-the-players flavour text for each encounter, the kind of evocative prose it's advocating is missing entirely from the module as printed.
I'll be clear: I wouldn't be caught dead reading flavour text to players. I'm comfortable enough coming up with my own narration that I can avoid the whole embarrassing experience of reciting this kind of florid fluff. But not everyone has 18 years of experience, and my hazy memory suggests that as a younger player I found these pre-prepped descriptions incredibly helpful. It's probably something beginning players really appreciate in an official adventure, and so in Keep, which is aimed at exactly those beginners, it's particularly horrible that the flavour text is so crap.
Let's look at a section from the Burial Site encounter:
A steep-sided crater punctures the wilderness. Near the center of the depression, several humanoid figures cluster around a collection of bones. Two small, dragonlike creatures near the crater rim stand alert and stare at your approach.How large is this crater? About 100 feet in diameter, but we only know that from the map because the description sure as hell doesn't give any clues. The mention of a "collection of bones" conjures up either a human corpse or humanoid remains, whereas in fact these are some frikkin' huge dragon bones we're talking about.
And "small dragonlike creatures" is totally unhelpful. Are these more of the "small dragonlike kobolds" the players have already encountered? Or are we talking the Monster Manual definition of a "small dragon" - ie, something in the Large size range with a wingspan of nearly thirty feet? As it turns out, these are guard drakes, about as large and menacing as a pit-bull, but players have no way of knowing that, and for that matter they're not even described to the Dungeon Master.
The mediocrity of the flavour text owes a lot to the way the module (and for that matter all 4th Edition modules) sets out encounters, with the entire encounter description crammed onto a two page spread. This is actually quite a nice design and makes encounters very easy to run, but, like most of the 4th Edition focus on combat, it comes at a cost to the storytelling.
 Were the designers at least aware of the compromises they were making to fit the format and deadline pressures? Or did they genuinely think that this was adequate flavour text?