How to Report Rain In a Weather Synoptic Observations (SYNOP)/ FM-12

A SYNOPTIC weather report is issued after every three hours. It is coded numerically and contains information about the weather of a particular weather station/area. It is coded as FM-12 by WMO. It contains weather information for the preceding three hours. Synop is issued at synoptic hours. Synoptic hours are 0000Z, 0300Z, 0600Z, 0900Z, 1200Z,1500Z, 1800Z and 2100Z.These are in  UTC timings. It has a proper structure and format to report weather information in coded form. In this article, we will only consider the rainfall reporting codes in SYNOP. To report rain in SYNOP follow the following instructions carefully.

A rainfall amount of 3 hrs (60007) is issued in every SYNOP in Section 3.

Rainfall of 24 hours ( 70000)  is issued in SYNOP of 0300 UTC in section 3.

Rainfall of 6 hours (60001) is reported in SYNOP of 0600 UTC in Section 1.

Rainfall of 12 hours (60002) is reported in SYNOP of 1200 and 0000 UTC in Section 1.

Rainfall of 18 hours (60003) is reported in SYNOP of 1800 UTC in section 1.

Rainfall at 0000Z:

At 0000Z we have to report rain of the preceding 12 hours in the 60002 group in section 1 and rainfall of the preceding three hours 60007 in section 3.

Example: If there is a rainfall of 4 mm from 1800Z to 2100Z and  2 mm from 2100Z to 0000Z. In 0000Z SYNOP we will have two rain groups.60062 in section 1 for 12 hours of rainfall and 60023 in section 3 for the preceding three hours of rainfall.

Rainfall at 0300Z:

At 0300Z we have to report rain of the preceding 24 hours in the 70000 group in section 3 and also rainfall of the preceding three hours  60007 in section three.

Example: If there is a rainfall of 4 mm from 1800Z to 2100Z and  2 mm from 2100Z to 0000Z. In 0300Z SYNOP we will have two rain groups.60003 in section 3 for 3 hours of rainfall (As there is zero rainfall in the preceding three hours) and 70060 in section 3 for the preceding three  24 hours of rainfall.

Rainfall at 0600Z:

At 0600Z we have to report rain of the preceding 06 hours in the 60001 group in section 1 and rainfall of the preceding three hours  60007 in section three.

Example: If there is a rainfall of 4 mm from 0000Z to 0300Z and  2 mm from 0300Z to 0600Z. In 0600Z SYNOP we will have two rain groups.60061 in section 1 for 12 hours of rainfall and 60023 in section 3 for the preceding three hours of rainfall.

Rainfall at 0900Z:

At 0900Z only rainfall of the preceding three hours is reported in the 60007 group in section 3.

Rainfall at 1200Z:

At 1200Z we have to report rain of the preceding 12 hours in the 60002 group in section 1 and rainfall of the preceding three hours  60007 in section three.

Example: If there is a rainfall of 4 mm from 0000Z to 0300Z and  2 mm from 0300Z to 0600Z. In 1200Z SYNOP we will have two rain groups.60062 in section 1 for 12 hours of rainfall and 60003 in section 3 for the preceding three hours of rainfall.

Rainfall at 1500Z:

At 1500Z only rainfall of the preceding three hours is reported in the 60007 group in section 3.

Rainfall at 1800Z:

At 1800Z we have to report rain of the preceding 18 hours in the 60003 group in section 1 and rainfall of the preceding three hours  60007 in section three.

Example: If there is a rainfall of 4 mm from 0000Z to 0300Z and  2 mm from 0300Z to 0600Z. In 1800Z SYNOP we will have two rain groups.60063 in section 1 for 18 hours of rainfall and 60003 in section 3 for the preceding three hours of rainfall.

Rainfall at 2100Z:

At 2100Z only rainfall of the preceding three hours is reported in the 60007 group in section 3.

Important Note:

In all rain groups starting from 6, the first and last digits are indicators i.e in 60007 6 and 7 are indicators. Rainfall information is coded in 000 between 6 and 7. 000 is in rounded whole number. If there is 1.2mm of rain in three hours it is reported as 60017.

Rainfall Code

Trace            69907

0.1 mm       69917

0.2mm        69927

.                 .

.                 .

0.9          69997

In 24 hours rainfall group i.e in 70000 last digit is a number after decimal i.e

trace   79999

Rainfall Code

0.1mm      70001

0.2mm      70002

5mm         70050

5.6mm       70056

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.

Related Posts

thunderstorm

The Difference Between Scattered and Isolated Thunderstorms

Thunderstorms are a common weather occurrence in many parts of the world, especially during the summer months. As someone who loves the outdoors, it’s important to understand…

temperature

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…

weather phenomenaon

What Are The Criteria To Report Haze, Smoke Haze, And Fog In METAR?

Meteorologists use the term “haze” to describe phenomena that obscure visibility.  The term “smoke haze” is used to describe a similar situation that occurs when smoke from…

Room Temperature in Kelvin

How To Reset Maximum and Minimum Thermometers?

Thermometers are instruments that are used for the measurement of temperature. At weather observatories, there are four types of thermometers used, which are placed inside a Stevenson…

snowfall measurement

How to Measure Snowfall Accurately and Easily?

Have you ever wondered how to measure snowfall accurately? If so, then you’re in luck, because today, we’re going to show you how to accurately measure snowfall…

METAR Codes

METAR Codes For Present weather According to WMO And ICAO Guidelines.Aviation Weather METAR Codes.

Pilots use METAR codes to communicate weather conditions to other pilots and air traffic controllers. These codes are defined by the World Meteorological Organization (WMO) and International…

Leave a Reply

Your email address will not be published. Required fields are marked *