Realistically? Everybody blabs blabs blabs about Cynops orientalis being not that temperature tolerant, however I keep and breed this species and they are maintained at a temperature range similar to the one you are describing. I have absolutely no problem with these newts at these temperatures. In their 3 year stint living with my not so vigilent boyfriend, and now over the past half-year living with me (I am generally more careful with the animals) there have been a number of successful breedings. I find they often breed more than once a year and the offspring grow up quickly and are breeding within 1.5 years. The only time I have ever had a problem was when they moved to my home last fall, and were actually placed in a cooler basement environment, one of the females decided to become reclusive and stopped eating. I isolated her in an aquatic tank and she is back to eating and behaving normally.
Anyway, my point is that the tank is about 24-26 C for about 2 months out of the year and the newts display absolutely no abnormal behavior during this time. I have had a friend who obtained offspring from me and her newts died in a heat-wave where the temperature in her apartment was over 30C for a number of days, but ultimately i think that if these newts are exposed to gradual temperature changes on an annual cycle they are generally OK. Does anybody else have this experience?