Discrepancies in the EO browser air temperature (Thermal layer of Landsat 8) and the actually recorded by weather station

For a spot in the Bekaa valley Lebanon, the graph from EO browser shows air temperature (thermal layer) range from around -4 to 40-degree centigrade. Even, -34 degree centigrade on March 31, 2019–it could be an outlier. While the actual weather data from a weather station shows a temperature range from 1.5 to 27-degree centigrade. Does the thermal layer mean, air temperature? if yes what can be the reason for the discrepancies?