Whats the lowest temperature a tabebuia tree can withstand?

I have them all over SW Florida. In January 2010, it hit 26 degrees here two nights in a row. Some of the smaller palm varieties were killed by the cold but the Tabenuia came through just fine but remember that is only two consecutive nights.
Would 5-7 nights in a row at that temperature kill them? I don't know.

Also, sometimes its not how low the temperature goes but how long it stays there and what the following daytime temperature is. So if BigBill's temperatures hit 25 but stayed there for only 30 minutes or so and then the daytime temps were in the 40's or 50's, there may be no damage at all. If the 26 temp lasted a couple hours and the next day high was only 30, the chance of damage would be much greater. And, as BigBIll pointed out, it was two nights, not two weeks.

The high temperature for the day between the 26's was 51.