If there is no tension in a story, who will keep reading past the first few pages? Other than someone paid to read it, of course…
My thoughts on this, take it or leave it.
Tension can be psychological or physical in nature.
There is no doubt that, handled correctly, throwing your protagonist into a weather catastrophe on page one can be a great tension creator (it can also be passé). The same can be said of a physical altercation, disaster in space, being caught in a house fire, finding a dead body, being lost at sea, or many other physical situations that can create tension. Fights and chase scenes are exceptionally good at introducing physical tension, but they are not the only methods. A protagonist experiencing a mystical event outside the realm of reality, which they treat as either common place or as a platform for wondering about their own sanity (thereby introducing psychological as well as physical tension), is a wonderful launch-pad with a lot of potential.
Developing an antagonist to pit your protagonist against, be it another character or a force of nature, is a great source for tension. If you go that route, be sure to use it fully, with forethought and the intent of working it intricately into the long-term plot. Remember, if your protagonist defeats the antagonist, the series is over – unless there is another antagonist waiting in the wings to step forward and become known. Often, having a vague but exceedingly evil antagonistic presence that is only rarely visited but never really faced during the full series, while having lesser antagonists for each book in the series, is not only a source of tension but also is a method of adding continuity to a series. This has the added benefit of not losing the antagonist totally while still providing the protagonist a chance to prevail against an adversary in each book.
Psychological tension can be more subtle and therefore more easily lost on some of your potential audiences – things like teenage angst, internal conversations of the lead character asking themselves what the right thing is (and do they really want to do it), struggling with major life changes while trying to refuse to accept them, a main character being in love with someone who is somehow unattainable – and not really knowing it even though everyone else around the two characters is waiting for them to get a clue, and so on. These often make great secondary plots, and can add to continuity throughout a series.
There is potential for tension all around you. Find it and develop it into a component of the plot that will capture your readers attention, keep them interested in the plot throughout the entire project, and leave them wondering if there is a sequel in the making.