Figure 13-10.  Surface analysis chart.  Figure 13-11.  Sample station model and weather chart symbols.  13-14  1. Total sky cover:  Overcast  2. Temperature/dew point:  34 °F/32 °F  3. Wind:  From the northwest at 20 knots  (relative to true north)  4. Present weather:  Continuous light snow  5. Sea level pressure:  1014.7 millibars  (mb)  Note: Pressure is always shown in 3 digits to the nearest tenth of a millibar.  For 1,000 mb or greater, prefix a “10” to the 3 digits  For less than 1,000 mb, prefix a “9” to the 3 digits  6. Pressure change in past 3 hours:  Increased steadily or unsteadily by 2.8 mb  Examples of Wind Speed and Direction Plots  NE / 5 kts  SW / 10 kts  N / 15 kts  W / 50 kts  S / 60 kts Calm  147  28 /  34  32  **  Pressure change in past 3 hours  Pressure tendency  Sea level pressure  Wind speed  Wind direction  Temperature  Total sky cover  Present weather  Dew point 