  We observed two eclipses of the Kepler-13A planetary system, on UT 2014 April
28 and UT 2014 October 13, in the near-infrared using Wide Field Camera 3 on
the Hubble Space Telescope. By using the nearby binary stars Kepler-13BC as a
reference, we were able to create a differential light curve for Kepler-13A
that had little of the systematics typically present in HST/WFC3
spectrophotometry. We measure a broadband (1.1$\mu$m to 1.65$\mu$m) eclipse
depth of $734\pm28$ ppm, and are able to measure the emission spectrum of the
planet at $R\approx50$ with an average precision of 70 ppm. We find that
Kepler-13Ab possesses a noninverted, monotonically decreasing vertical
temperature profile. We exclude an isothermal profile and an inverted profile
at more than 3$\sigma$. We also find that the dayside emission of Kepler-13Ab
appears generally similar to an isolated M7 brown dwarf at a similar effective
temperature. Due to the relatively high mass and surface gravity of
Kepler-13Ab, we suggest that the apparent lack of an inversion is due to
cold-trap processes in the planet's atmosphere. Using a toy model for where
cold-traps should inhibit inversions, and observations of other planets in this
temperature range with measured emission spectra, we argue that with more
detailed modeling and more observations we may be able to place useful
constraints on the size of condensates on the daysides of hot Jupiters.
