This was the day. The one in your imagination. Or your memory. On your movie screens. When Paris is sunny and beautiful and lively and almost dream-like in it scrumptious goodness and magnetic appeal and all those recreational options, options, options!

For two weeks here, it was mostly cloudy. Even rainy. Which suited a couple of people escaping the summer heat of Abu Dhabi just fine. Rain? Temps in the 60s? Bring it on.

Today, however, was what the first-time tourists, the young lovers, the romantics and the epicures want from their Paris vacations. And it isn’t about stubborn clouds and rain.

It was sun. Glorious sun. Temperatures crossing 80 Fahrenheit by noon. Coats and sweaters left behind in hotel rooms and apartments. Sandals and short pants and T-shirts and summer dresses.

Every cafe with its full compliment of terrace seating. Lines for “glaces et sorbets” at the windows of sweet shops. Paris Plage — the “beach” the city puts up on the right bank of the river during the summer — crawling with smiling people. Buskers swarming the open areas where tourists stroll.

I got a full dose of it during my walk from the Marais over to the Ile de la Cite. Going over the bridge to Ile St. Louis, I saw all the people on the “beach.” Then onto the Ile St. Louis, crowded but relentlessly charming. And then over the little bridge that links Ile St. Louis to Ile de la Cite, the bridge the buskers like. A four-piece band playing to appreciative tourists (“What a Wonderful World” gets a lot of air time), and at the other end of the bridge a guy working hard on his accordion.

Another accordionist — a hideous instrument, really, but a thing of beauty inside the peripherique that forms the borders of the city — playing all the old accordion standbys, one of which now includes the theme from “The Godfather.” Hmmm.

Couples and families clustered on the benches beneath the broad leaves of plane trees. The gravel of the park crunching under the feet. Groups of older tourists pouring out of big buses and following their guide into the square, where the guide points out the interesting features of the altar (eastern) end of Notre Dame. “See the flying buttresses? The stained glass?”

Kids playing on playground equipment. Their parents eating panini and crepes  and baguette sandwiches they bought from the touristy shops across the street. A young man with an “I ad(heart)re Paris!” T-shirt, holding hands with his even younger girlfriend, in their own cocoon of bliss. Another young man singing, in English, “I love Paris …” Really.

I felt almost disconnected, as I slogged around the edges of the square, the same place I jogged last August. All the happiness around me was almost palpable, almost contagious. I was suffering in the heat — 87-88 is a bit warm for a jog — but how could I be beaten down when giggling 3-year-olds were chasing pigeons and never quite catching them?

This was one of those days. When anyone who is in Paris knows exactly why they came, why they will miss it when they are gone, why they remember it so fondly.