On a station model, reading the temperature is pretty easy. The number located in the upper-left corner of the model is the station temperature expressed in degrees Fahrenheit (or Celsius, depending on the country of origin). In the case of the station model on the right, the temperature is 52 degrees Fahrenheit.

What does a station model show you?

Meteorologists created the station model to fit a number of weather elements into a small space on weather maps. This allows map users to analyze patterns in atmospheric pressure, temperature, wind speed and direction, cloud cover, precipitation, and other parameters.

What does a circle around a weather station mean?

The wind direction is plotted as the shaft of an arrow extending from the station circle toward the direction from which the wind is blowing. The wind speed is plotted as feathers and half-feathers representing 10 and 5 knots, on the shaft on the wind direction arrow.

What do the symbols on a weather map mean?

The large letters (Blue H’s and red L’s) on weather maps indicate high- and low-pressure centers. They mark where the air pressure is highest and lowest relative to the surrounding air and are often labeled with a three- or four-digit pressure reading in millibars.

What symbols are used in a station model?

In the center of the station model is a symbol or picture that represents two things: the cloud cover and the wind speed. The central circle represents the cloud cover. A black circle means the sky is completely overcast and cloudy, and a white or empty circle means that the sky is completely clear of clouds.

How do you read barometric pressure on a station model?

The three digits in the upper-right-hand corner of the station model represent the last three digits of the station’s sea-level pressure, expressed to the nearest tenth of a millibar. Thus, to decode the pressure reading, you must first add a decimal in front of the right-most digit.

What is the meaning of DD in a station model?

dd – Wind direction: The line drawn represents the direction from which the wind is blowing. … ff – Wind speed: The barbs on the lines representing wind direction give us information on the wind speed. Wind speed is measured in knots (1 knot =1.15 miles per hour).

What do red wind barbs mean?

The stick points in the direction the winds are coming from. Each full barb represents 10 knots of wind. Each half barb represents 5 knots. Red represents wind gusts.

What is the temperature according to the station model?

Dew PointGeneral level of comfort70 degreesThe air is sultry and tropical and generally uncomfortable.

How do you measure humidity in a station model?

Once you have the saturation vapor pressure and the actual vapor pressure, relative humidity can be computed by dividing the actual vapor pressure by the saturation vapor pressure and then multiplying by 100 to convert the quantity to a percent.

Article first time published on

How do you read weather numbers?

There will be two numbers. The higher number is the forecast maximum temperature for the day. The lower number is the minimum temperature. Take note of the forecast weather conditions.

How do you read cold and warm fronts?

Cold Front Phrases like “ahead of the front” and “behind of the front” refer to its motion. So being “ahead of the cold front” is being in the “warm” air mass and “behind of the cold front” is in the cold air mass. Also remember however, the terms “cold” and “warm” are relative.

What do the red and blue lines mean on a weather map?

On a weather map, a warm front is usually drawn using a solid red line with half circles pointing in the direction of the cold air that will be replaced. … On a weather map, a cold front is usually drawn using a solid blue line with triangles pointing in the direction of the warm air that will be replaced.

How do you read a pressure trend?

The pressure trend has two components, a number and symbol, to indicate how much (in tenths of millibars) in the past 3 hours and the trend in the change of the pressure during the same period. In above case, the pressure was falling after steady or slightly rising and becoming 3 mb LOWER than it was three hours ago.

What unit is used for air pressure on station models?

1. The station model uses an encoded format of the air pressure in millibars.

What does it mean when isobars on a map are close together?

When two isobars are closer together then the pressure changes at a greater rate over distance. It is pressure differences that set the air in motion. When isobars are spaced far apart then the pressure changes more gradually over distance and thus the wind speed is weaker.

What does a half feather barb on a wind direction symbol indicates?

A half-length feather indicates 5 knots; a full-length one 10 knots; and a pennant (a small triangular ‘flag’) is used for 50 knots. Originally a half-length feather indicated a Beaufort force of 1 (see Beaufort Scale), and a full feather a Beaufort force of 2.

What's the difference between barometric pressure and station pressure?

Station pressure is measured at a station without any adjustment. … With barometric pressure, it’s the station pressure adjusted to the mean sea level. If the pressure is measured at sea level, station pressure and barometric pressure are equal. Keep in mind that barometric pressure changes with density altitude.

How do you read wind symbols?

The staff part of a wind barb shows wind direction. The dot end of the staff is where the wind is blowing to, while the top of the staff shows the direction from which the wind is coming. The top row of wind barbs in the figure to the right all indicate a north wind.

How is Rh value calculated?

Divide actual vapor pressure by saturation vapor pressure and multiply by 100 to obtain a percentage using the formula Relative Humidity (percentage) = actual vapor pressure/saturated vapor pressure x100. The resulting number indicates relative humidity.

How do you read rain weather?

occurring at any one spot in the area covered by the forecast. One simple equation used among meteorologists is P = C x A, or the probability of precipitation equals the meteorologist’s confidence that it will rain, times the percentage of the area that is expected to get rainfall.

How do you read the weather in the rain?

According to the National Weather Service, Probability of Precipitation or (PoP) is “PoP = C x A where “C” = the confidence that precipitation will occur somewhere in the forecast area, and where “A” = the percent of the area that will receive measurable precipitation, if it occurs at all.”