How to Report Maximum and Minimum Temperature in Weather SYNOP?

SYNOP is a coded data format of weather that contains all the weather information. Meteorological weather SYNOP is issued after every three hours. There are standard timings of issuance of SYNOP. According to WMO standard SYNOP is issued at 0000Z, 0300Z, 0600Z, 0900Z, 1200Z, 1500Z, 1800Z, 2100Z UTC. In this post, we will discuss how and when to report maximum and minimum temperatures in weather SYNOP. The maximum temperature is the highest recorded temperature in the last 24 hours. The minimum temperature is the lowest recorded temperature in the last 24 hours.

How to Report Maximum temperature in Weather SYNOP:

The maximum temperature is the highest temperature which is recorded by the maximum thermometer. The maximum thermometer is used to record maximum temperature. The maximum thermometer is built in such a way that with rising in temperature its reading increases. It’s reading not falls back with a drop of temperature hence it shows the maximum value of temperature reached after it is reset.

Reading of the maximum thermometer is noted and reported at 1200Z UTC. It is being reset at 0300Z UTC daily.

How to reset a maximum thermometer: Take out the maximum thermometer from the Stevenson screen. Jerk it slightly when the temperature reaches near to the current temperature and settles down then put back the maximum thermometer in the Stevenson’s screen.

The maximum temperature is reported in section 3 of weather SYNOP in  1TsTxTxTx group at 1200Z SYNOP.Ts indicates sign. For positive value, it is 0, and 1 for negative. TxTx indicates the first two digits. The last Tx is after a decimal point digit. e.g If the maximum temperature is 30.1 C. It is reported as 10301. If the maximum temperature is -2.1 it is reported ad 11021.

If maximum temperature occurs after 1200Z (rare case) then the maximum temperature is again reported in SYNOP of 1500Z.

How to Report Minimum temperature in Weather SYNOP:

Reporting of minimum temperature in SYNOP is similar to that of maximum temperature only difference is that minimum temperature is reported at 0300Z.

Take a reading of the minimum thermometer at 0300Z. After taking readings reset the minimum and maximum thermometer. The minimum temperature is reported in section 3 of SYNOP in group 2TsTnTnTn.

Tn indicates sign. 0 is for positive and 1 is for a negative value.

TnTnTn indicates temperature. First TnTn is 1st  two digits. The last Tn is after the decimal point. If the minimum temperature is -2.1 C. It is written as 21021. If the minimum temperature is +2.1 it is written as 20021.

In conclusion, the maximum temperature is usually reached at noon and the minimum temperature is usually reached in the early morning hours. The highest temperature is usually reached in summer and the lowest temperature is usually reached in winter. The minimum temperature is usually reached in January and the maximum temperature is usually reached in July. 

Holds BS Degree in Electrical Engineering and MS Degree in Meteorology and currently working in the field of meteorology as an assistant weather forecaster. Love helping people know what the weather is doing. Researcher of the weather conditions and make forecasts for several different locations.

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