This is my first winter with a one year in the ground red navel. The red navel from what I have read has about the same cold hardness as my Meyer lemon. Is that right?

This is what I use.

Satsuma cold-hardiness down to about 20F with fruit damage at 25F

Meyer lemon tolerate temperatures down to about 26F

Red Navel 26F same as Meyer Lemon

Ran across this and thought it might be helpful.
Some years, citrus plants seem to freeze at higher temperatures. The contributing factor seems to be the difference between air (ambient) temperature and leaf (tissue) temperature. On a windy night with clear or cloudy skies, leaf temperature will be approximately the same as air temperature. On a cold, clear night with little or no wind movement, leaf temperature may easily drop 3 to 4 degrees F below air temperature because of radiation heat loss. Thus, under the latter circumstances, while the minimum air temperature on a given night may have only been 25 degrees F, actual leaf temperature may have reached 21 to 22 degrees F. The critical temperature is that of the leaf or fruit, not the air.