Welcome to hot weather and short tempers. To rowdy crowds and postseason atmospheres. To wild celebrations on one side of the diamond and gut-punch losses on the other.

Mets manager Mickey Callaway said he has been spending an extra few pregame moments on the field to understand how ready fans are to be part of his team’s magical ride.

No single game decides anything at this point in the season, although almost every one has precisely that feel. Don’t you just love August baseball?

In the National League, at least 11 of 15 teams still have postseason aspirations. Meanwhile, the Indians and Twins seem so evenly matched that they could take the American League Central race down to the final week.

• MLB standings

That’s true of the AL Wild Card race, as well, with the Red Sox trying to get within striking distance of the A’s, Rays and AL Central runner-up. Weeks like this are a reminder that there has seldom been a better time to be a baseball fan.

Here are what appear to be the five most interesting series of the week:

1) Mets at Braves

The Braves almost have passed every test this season and have been alone atop the NL East since June 12. Now comes a team that has won 15 of its last 17 games thanks to a rotation that has been baseball’s best and appears to be capable of taking the Mets on a ride deep into October. The Mets and Braves play six times over the next two weeks, so we’re about to find out plenty about both clubs.

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2) Reds at Nationals

First, you acquire an upgrade for your rotation. Then you watch an amazing rookie burst onto the scene and lift an entire club. If there’s a blueprint for making the postseason, these surely are two of the ingredients, and the Reds have gotten both with the trade for right-hander Trevor Bauer and the arrival of rookie outfielder Aristides Aquino, who is hitting .452 and had seven home runs in his first 10 career games. The Nationals, who are 43-24 since their 19-31 start, are trying to write their own improbable story.

3) Red Sox at Indians

Remember when a lot of fans had written off the Indians and expected the Red Sox to take off any day? Turns out, it’s the Indians who got hot, going 43-18 since June 1 to tie the Twins for first place in the AL Central after winning in Minnesota on Sunday. As for the Red Sox, every series is more and more important as they fight just to get back to the postseason.

4) Cubs at Phillies

Despite all the injuries and tough losses, the Phillies are still right in the middle of the jumbled NL postseason race. Jake Arrieta and Aaron Nola offer hope for a disappointing rotation, while Bryce Harper could be one hot streak from making September special. The Cubs have been atop the NL Central for most of the last six weeks but have little wiggle room with the Brewers and Cardinals on their tails.

5) Twins at Brewers

This two-game series might as well be a postseason series for two teams that have little margin for error. The Twins, who led the AL Central by 11 games in June, are tied with the Indians while their starting rotation, which was so solid early in the season, has hit a rough patch. The Brewers got back on track with a five-game winning streak that was snapped by the Rangers on Sunday. Now, Milwaukee begins a 23-game stretch against teams that still have postseason hopes. These next three weeks could define the Brew Crew's season.