Predicting drinking windows (cellaring potential if one prefers) is based on a number of factors, some that can be gained entirely from earlier experience and others that are dependent entirely on the varieties of grapes and the winemaking methods.
1. History of the specific wine in question as compared to the track record of previous vintage releases. To some great extent comparison must also be made in the variety or the blend
2. Knowledge of the qualities of the current and past vintage years
3. Familiarity, when necessary, of winemaking procedures with the wine (e.g.use of oak, new or changed methods of harvest, introduction to the winery of new owners, a new major winemaker or the use of a specific wine consultant and his/her track record)
Specific Oenological Elements:
1. Knowledge of varietals and their ability to age as well as of familiarity with the wine-growing region, the more detailed the knowledge the better one's predictive ability
2. Structure – The perception of wood, tannins, acidity, fruits and other elements that make up the flavor and aroma of the wine. In the case of a wine with an extended drinking window those should stand comfortably together and, during the youth of the showing the potential for the elements to develop in a harmonious manner.
3. Balance – As opposed to structure, a cellar-worthy wine must show an intrinsic balance potential even in its youth. That a wine may show heavy oak or dominating tannins in its youth is not to be held against its aging potential so long as those elements show (and/or have demonstrated in the past) the ability for those elements to find their ideal structure as they develop.
4. Potential faults – One cannot lose consideration of factors of sediment, potential oxidation and, faults such as TCAor Brett, early browning or clearing at the rim; tainted aromas or flavors.
5. Make and keep tasting notes as those will help the data enter into long-term memory. I suppose author Ray Bradbury put it rather well when he said "I know you've heard it a thousand times before. But it's true –hard work pays off. If you want to be good, you have to practice, practice, practice. If you don't love something, then don't do it"
6. No less important, especially for the professional or other true wine devotee, is the ability to at least periodically carry out re-tastings, those often together not only with the specific wine at issue but others in the same or similar conditions and over the period of many years, that as a check on one's predictive abilities.