Temperature is measuring how warm or cold miscellaneous is, such together the exterior air temperature, her body temperature, temperature that water for cooking, boiling, washing, etc.

You are watching: How hot is 31 degrees celsius

So, is it cold or hot when the temperature forecast says it will certainly be 5 degrees or it will be 30 degrees? What temperature go water freeze at? Or cook at? What temperature is comfortable for your living room?


Using the contemporary Celsius mechanism of temperature measurement, we can conveniently determine how warm or cold that is. The was additionally known together Centigrade. This is since it is based on the freezing and also boiling points of water with 100 degrees in between those temperatures.

The main SI unit the temperature is the kelvin, which steps absolute temperatures. But, because that our daily usage, we usage Celsius i beg your pardon is straight related to kelvins. It is collection so that pure water freezes in ~ zero levels Celsius and boils in ~ one hundred levels Celsius.

This is a very easy device to learn as these 2 marker points room so simple to remember:

Freezing in ~ 0 °C

Boiling at 100 °C

And v 100 degrees between those points, we deserve to specify temperatures making use of 1 or 2 digit hopeful numbers. As soon as the temperature is negative, i.e. Below 0 °C, climate we recognize that it is for this reason cold that water will freeze. Water will constantly be ice below 0 °C, fluid from 1 to 99 °C, and steam from 100 °C upwards.

Here is a table reflecting some guidelines as to Celsius temperatures:

Temperature °CWhat might be at this temperatureHow the feelsOther point out of interest

-30 (that is 30 degrees listed below zero)

Ice, freezer

Very cold if friend are external in this temperature, unbearable come most




Very cold still but bearable if in lots of warmth clothes



Water freezes, ice melts


Typical coldest median temperature because that UK in winter




Water has its smallest volume in ~ this temperature*





20Room indoorsWarm
25Warm roomWarm to hot
Typical maximum temperature because that British summer
30Hot dayFeeling hotTypical temperature because that hotter countries


Body temperature

Very hot

This is the average human body temperature

40Washing device setting for clothing for typical washVery hot
If friend are exterior in this temperature you will feel hot, but much more so if humidity is high.If your inner body temperature reaches this level you are in peril of death.
50Extremely hotNot countless places get this high in temperature, and this heat you would need to uncover shade, drink water and stay cool.
60Washing machine setting for warm wash
Too hot to live inMost bacteria die at this temperature
90Washing an equipment setting because that hottest washToo hot to live inHumans cannot survive such high temperatures
100Water boils in the kettle

Water transforms to steam
1000Lava indigenous a volcano

1535Melting point of iron


15 000 000

Core that the Sun

*Note that water increases as that is temperature increases above 4 degrees, and as that goes colder below 4 degrees. Its volume will be at its smallest at 4 °C. This is vital to remember when freezing water in the icebox or freezer, together the water will certainly undoubtedly boost in volume together it freezes, and also the chillier it gets, the larger the ice cream gets. For this reason remember no to placed water right into a bottle that will certainly be in the freezer for an ext than a minute or so, as the water inside will expand and break the bottle.

If you have to work in warm conditions, here are guidelines because that rest durations needed:

TemperatureRest duration (per hour the work)

30 come 32 ºC

10 minutes

32 to 35 ºC

15 minutes

more than 35 ºC

at least 30 minutes

Remember that as soon as you see a weather estimate on TV, in a newspaper or ~ above the radio, the anything native 20 degrees upwards is walking to it is in warm, above 25 degrees is hot, over 30 degrees is really hot. Listed below 20 is cool, listed below 10 degrees is cold, and also below zero degrees means that it will be icy exterior as the water will certainly freeze and it will feel an extremely cold outside.

Kelvin (for the much more scientific amongst us)

The kelvin (symbol: K) is the SI unit the temperature, and also is among the 7 SI base units. It is defined by 2 facts: zero kelvin is absolute zero (when molecular motion stops), and one kelvin is the fraction 1/273.16 the the thermodynamic temperature the the triple point of water (0.01 °C). The Celsius temperature range is now identified in terms of the kelvin.

The kelvin is called after the british physicist and also engineer william Thomson, first Baron Kelvin. For this reason we have one more metric unit named after a brother person. Many metric units are not foreign at all, uneven °F i beg your pardon is Foreign! The level Celsius (°C) is named after the sweden astronomer Anders Celsius (1701–1744) but as the is now defined in terms of the kelvin, it is more British 보다 Fahrenheit, called after a German scientist.

The word kelvin together an SI unit is appropriately written with a lowercase k (unless in ~ the beginning of a sentence), and also is never preceded by the words level or degrees, or the symbol °, uneven Celsius. This is because Celsius is a scale of measurement, vice versa, the kelvin is a unit of measurement.

See more: What Food Does Not Support Bacteria Growth

The freezing point of water, together we know from what we review above, is 0 °C, and also 0 °C = 273.15 K. Because that every boost by 1 °C the temperature likewise increases by 1 K. Therefore 0 K = -273.15 °C, 100 K = -173.15 °C, 273.15 K = 0 °C, and the boiling suggest of water is 373.15 K (100 °C).