In the Northern hemisphere the summer is warmer than the winter (i.e. normal), in the Southern hemisphere the winter is warmer than the summer (i.e. Australian), around the equator there is not much difference during the year.
What: The difference between monthly mean temperature and annual mean temperature. When: Some weather stations have data since the XVIII century. Where: All the weather stations in the world binned at each 10th latitude. Only stations with full-year datasets used in calculations. Source: Global Historical Climatology Network-Monthly (GHCN-M) temperature dataset https://www.ncdc.noaa.gov/ghcn-monthly
The question arises because we’re having Climate Change and not Global Warming. Only 6 weather stations in the world have a statistically significant negative temperature trend since 2000. Most of them are located around the equator, one is in Antarctica. There are 391 weather stations that have at least 5 full years of data since 2000 and which have a significant trend (p-value is less than 5%). In 385 of those stations, the temperature is rising.
When: 2000 January – 2020 December. Where: Weather stations that have at least 5 full years of data during the period in question and have a significant regression coefficient (p-value < 5%). Source: Global Historical Climatology Network-Monthly (GHCN-M) temperature dataset https://www.ncdc.noaa.gov/ghcn-monthly