Help Information

Interpreting Station Plots
Station plot diagram
Wind speed
The sustained wind is shown using a wind barb. The barb indicates both the wind speed and direction. For most stations, the sustained wind is the average wind speed and direction in the two minutes prior to the map time. More information about how to interpret wind barbs can be found at: https://www.wikihow.com/Read-Wind-Barbs
Sea level pressure
Sea level pressure is shown as a truncated 3-digit number in the upper-right corner of the station plot (when available). In the station plot above, the value of 070 corresponds a pressure of 1007.0 hPa. The 3-digit pressure value was converted back to a full pressure reading using the following formula: If the truncated value is below 500, put a 10 in front. If the value is above 500, put a 9 in front. The pressure value is commonly truncated on surface maps to save space.
Wind gust
If the station recorded a wind gust over 16 knots, it is shown on the station plot. Some stations record gusts over the entire previous hour, while some only report over the 10 minutes immediately prior to the time of map. If the station plot does not show a wind gust, the wind speed was either too low, or the station does not report wind gusts. If no wind gust is shown, this slot is sometimes used to show the station identifier (see below for more information).
Hourly / 24-hr precip
The hourly and 24-hr precipitation values are shown in the lower-left corner of the station plot. They are only plotted if greater than 0 mm. The hourly precipitation value is a non-bold blue number. The 24-hr precipitation is a bold blue number. In some cases only one of the two values may be reported. Some stations do no measure precipitation at all, in which case no value is shown. The 24-hr value is the total precipitation over the previous 24 hours. However, for Manitoba Agriculture stations this is the total precipitation reported since midnight for that calendar day in central time. If no precipitation value is reported, this slot is used to show the station identifier (see below for more information).
Station location
The black dot at the tip of the wind barb is the actual location of the station.
Dewpoint
The dewpoint temperature is given as a green value in degrees Celsius. It is the dewpoint value measured at the time of the surface map.
Air Temperature
The air temperature is given as a red value in degrees Celsius. It is the air temperature value measured at the time of the surface map.
Station identifier
The station identifier is plotted in the lower-left corner of the station plot if no precipitation measurement is reported. If precipitation is recorded, the station identifier is plotted in the wind gust slot. If both precipitation and wind gusts are reported, the station identifier is not shown. The stations plotted on these maps come from numerous seperate observing networks and may not follow national or international code tables. If the station identifier is nan, the identification code could not be found.