What does it mean that the weather and rain show 30% in Apple 5s?

It means that there is a 30% chance that it will rain in the corresponding period. This probability is calculated according to the weather forecast and the size and trend of rain clouds.

Weather: refers to the specific state of the atmosphere near the surface in a short period of time. Weather phenomenon refers to various natural phenomena in the atmosphere, that is, the comprehensive expression of the spatial distribution of various meteorological elements in the atmosphere (such as temperature, pressure, humidity, wind, clouds, fog, rain, flash, snow, frost, thunder, hail, haze, etc.). ) in an instant.

Why it rains: Rain is water drops falling from the clouds. Water on land and sea surface evaporates into water vapor. Water vapor rises to a certain height and turns into water droplets when it is cold. These small water droplets form clouds. They collide with each other in the cloud and merge into large water droplets. When it is too big for the air, it will fall from the clouds and form rain.

Classification:

1, and the rainfall classification standard is: it is light rain when the daily precipitation is between 0- 10 mm; 10-25mm is moderate rain; Heavy rain between 25 and 50 mm; 50- 100 mm is a rainstorm; The rainstorm falls between 100-200mm, and the rainstorm falls above 200mm.

2. According to the causes of precipitation, there are convective rain, frontal rain, topographic precipitation and typhoon rain (cyclone rain).

3. According to the form of precipitation: snowfall, rainfall and hail.

Meteorological terms:

1, time division: the daytime mentioned in the weather forecast refers to 8: 00 to 20: 00 local standard time, in which 17: 00 to 20: 00 is called evening; Call night after 20 o'clock to 8 o'clock the next day.

2. Fog: A visible aggregate of a large number of tiny water droplets (or ice crystals) suspended in the atmosphere near the ground. The only difference between fog and clouds is whether they touch the ground or not. Fog greatly reduces the horizontal visibility of the ground. According to the regulations of the International Meteorological Organization, when the visibility drops below 1 km, it is called fog.

3. Temperature: The temperature mentioned in the weather forecast refers to the air temperature measured in the open air without direct sunlight (generally measured by blinds). The highest temperature is the highest temperature in a day, which generally appears at 14- 15, and the lowest temperature generally appears at 5-6 am.

4. Wind: Wind refers to the horizontal flow of air. Expressed by wind direction and wind speed: the wind direction is divided into sixteen directions, which refers to the direction in which the wind blows; Wind speed is expressed in wind scale or m/s, and it is divided into average wind speed represented by 2-minute average situation and instantaneous wind speed represented by instantaneous situation.

5. Snowfall is divided into light snow, medium snow, heavy snow, blizzard and blizzard according to snowfall. Among them, blizzard is the snow with high snowfall intensity (the horizontal visibility distance is less than 500m during snowfall or the snowfall within 24 hours is greater than15 mm); Blizzard, also known as blizzard, is a weather phenomenon that strong winds carry a lot of snow and it is impossible to judge whether there is snowfall at that time, and the horizontal visibility is less than 1km.