Temperature reading not always highest or lowest
Past, current or predicted temperature values displayed in a weather report may not always represent the warmest or coldest temperature for a location on a particular day.
Past and current temperatures
Past and current temperature readings displayed in a weather report are usually recorded at specific times in a day. Depending on the time interval between 2 readings, the values may not represent the actual maximum or minimum temperature. For example, if the temperature is recorded at 1:00 p.m. (13:00) and again at 2:00 p.m. (14:00) but the actual temperature peaks at 1:30 p.m. (13:30), the readings for the maximum temperature will be a little too low.
The temperature readings also depend on the location of the weather station. In some cases, a weather station may be at a higher altitude than the center of the city it represents. In this case, the temperature readings will generally be too low as a higher altitude usually means a lower temperature.
As predictions of future events, weather forecasts can only provide approximations of expected weather conditions. The predicted high and low temperatures are therefore just sample values indicating what to expect with regard to the day’s temperature.
What affects temperature readings?
Air temperature generally varies from day to night because of changes in the amount of radiation heating Earth’s atmosphere. Air temperature also changes with the seasons. Summers are warmer than winters except near the equator where temperatures are fairly constant throughout the year. The Sun is higher in the sky and days are longer in the summer.
The intensity of sunlight striking the Earth’s surface increases when the Sun is higher above the horizon. More sunlight hours in a day could mean more solar heating at a particular place. Altitude also affects air temperature. The air temperature generally drops within the troposphere so it is usually colder on a mountain top than in the lowlands.