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tokens: peak temperature that we have previously reported (Jennings et al. 2011 , 2016 ) continued through late northern spring to the solstice. The latitude of maximum temperature (center of north–south symmetry) closely tracked the subsolar point from 13 S in 2005 to 24 N in 2017. We find a non-zero phase offset that corresponds to a small seasonal lag at equinox, about 0.1 Titan months. Figure 1 shows that a small lag is consistent with the non-uniform GCM case, although it is not as clear that there is a lag in the uniform case (see also Tokano 2019 , Figure 3). Our seasonal lag agrees with that reported by Janssen et al. ( 2016 ) and is also in line with the observations of Voyager 1 IRIS near the previous equinox in 1980 November (Flasar et al. 1981 ; Courtin Kim 2002 ). A small lag is consistent with the low thermal inertia required of the surface for diurnal variations (Cottini et al. 2012 ). Our equatorial temperature of 93.5 ± 0.4 K at equinox ( L s = 0°) agrees with the Voyager IRIS measurement, 93 ± 1 K (Courtin Kim 2002 ). From early to late in the mission the maximum amplitude of the cosine dropped by about 1 K, from 93.9 to 92.8 K. The time-dependent width in formula (1) signifies a “flattening” of the temperature distribution as the peak moved north, i.e., a more gradual fall-off toward the poles. An examination of the measurements and of the fitted cosines suggests that, although the peak temperature decreased, the average of north and south pole temperatures in each period remained approximately the same throughout all seven periods. Our formula can be used to inspect the change in surface temperature at any particular latitude over the two-season mission. For example, at the Huygens landing site, 10 S, the temperature ranged from 93.9 to 92.5 K between 2005 and 2017. Because the peak temperature decreased as it shifted northward, the semi-annual temperature variation was strongly dependent on latitude. The temperature variation was greatest at 40 S (93.6–91.7 K), where the surface was relatively dry, and was smallest at 40 N (92.6–92.7 K), where surface temperatures were moderated by the wetter north (Lora et al. 2015 ; Tokano 2019 ). Changes in surface condensation must be much less at mid-northern than at mid-southern latitudes. At 40 S between winter and summer, vapor pressures would have increased by a factor of 1.26 for methane and 1.61 for ethane while at 40 N they would have varied by only factors of 1.01 and 1.03. Any northward migration of volatiles while the south is warmer will not be fully undone later in the yearly cycle because the northern temperatures never get as warm as in the south. The temperature ranges at the poles were virtually identical: 91.9–89.8 K at 80 S and 89.9–91.9 K at 80 N. Both poles, at their coldest, reached the triple points for methane (90.7 K) and ethane (90.3 K). The poles may at times harbor both liquid and solid phases. Overall our results indicate that the northern hemisphere presents a