The summer chess tournament season is upon us, and I recently played in both the National Open in Las Vegas and the World Open in Philadelphia, just four days apart.

The National was held at the Westgate, a very long block from the main Vegas strip. The heat was incredible, 100 plus degrees, day and night. But the tournament was very well run, as it has always been.

There were about 619 players in all sections. The room was large, and lighting very good. Sets and boards were provided. Something new to me was that every board in the open section played with a Monroi notation device or a DGT board for live Internet broadcasts of the games.

I played so-so chess, finishing with an even score (3-3) and gaining just one rating point.

The young Texan Ruifeng Li and German Daniel Fridman tied for first, earning $6,000 each.

I took a red-eye back to Boston for a day and then it was off to the 44th World Open, more about that event next week.

The US Girls Junior Championship finished up in Manchester N.H. After a very exciting last two rounds, 13-year-old Texan Emily Nguyen, the sixth-highest rated player, emerged as the surprise winner with 6.5 points, earning $2,000. The key moment was her eighth-round win over Carissa Yip. In second was Californian Agate Bykovtsev, with 6 points. Texan Evan Xiang finished third on tie-break over Yip, who finished in fourth, both with 5.5 points.

Winners: Wachusett Championship: “A’’ Division: cochampions: Ray Paulson and Roger Cappallo: 3.5-.5, “B’’ Division: 1st: Larry Gladding, 5-0; Billerica June Swiss: 1st: Tim Bromley, Ray Paulson, 3-1

Coming events:Boylston $15 Open, July 16, 40 Norris St., Cambridge, www.BoylstonChess.org; 52nd Papa Gino’s Open, July 17, Papa Gino’s Waltham, 1018 Lexington St., Waltham, MatthewGosselin24@yahoo.com.

Answer to today’s problem: 1:Rf8+! Rxf8 (1…Bxf8 2.Qg8 mate) 2.Qg8+! Rxg8 3.Nf7 the always popular smothered mate.

Chris Chase can be reached at BostonGlobeChessNotes@Gmail.com.