Is the movie set in TV Series continuity?

No. It's outside the continuity.

No, it's not canon at all. Totally not canon. Basically, Just for entertainment.

No Day But Today. Today 4 U. One Song Glory.
How we gonna pay last year's RENT?!

Yeah, an 'entertainment value' alternate reality, the prologue even establishes the team started out with six members as opposed to five. Rita and Zedd's group had a monster seen nowhere in the series (thank goodness), the Rangers already had their upgraded suits without explanation that never get seen in the series, weapons/head-equipment gets used that was never seen (other than Saba), Ninjetti zords also looked somewhat different from the Season 3(/Kakuranger) Ninja zords. And obviously, the four part "Ninja Quest" story that practically opens Season 3 shows a totally different version of events for how the original Mighty Morphin' powers get fractured, the team's quest for new powers, along with their attainment of the Ninja variation and new zords.

I personally prefer Season 3's four-parter over the movie for many reasons. The characters seem much truer to their personalities of the show, they aren't just cardboard copies whose any line of dialogue could be the other's (which was already a problem with Rocky and Adam IMO). The emotion at genuinely seeing the Rangers lose their original zords, the Dino zords even being the foundation for their Thunder zords and hence why it hit Kim all the more, was particularly a highlight that Rito's campy character couldn't even ruin. I may prefer Dulcea over Ninjor, but in terms of overall story and character emotions, the series is what I'd sooner watch. Oh yeah, plus we get to see how Bulk & Skull become Junior P.D. cops, a can't-miss subplot!

So yeah, think of Mighty Morphin' Power Rangers: The Movie as an alternate reality similar to the RPM season, while the RPM timeline seems to have diverged from the other shows at least as of 2008.

Superman & The [Red-Blue] Blur = The Man of Steel

If you watched the show back then you'd know it's a stand alone movie - assuming the views know the previous series, but it has a starwars like story filler on the start just to keep people in the know.

And instead the tv series got a goofy bloke called ninjor that ninjarised the team. Along with rita's brother rito taking ivan's place. It was beginning of the end of the little credibility it had.

I think fans who call it non-canon are pretty silly and anal retentive. It can easily be seen as a one-off adventure. The has all the same characters from the show for crying out loud. But all of a sudden a pig guy is enough to make people flip out over something not being canon? The Power Rangers series has really loose continuity anyway. It's not the most well written and structured show ever. I see no real reason why the film cant be canon.

It's like the Never Say Never Again of Mighty Morphin Power Rangers, it has the original TV actors but sits on it's own and isn't part of the official TV continuity.