WEATHER FORECASTS FOR SALT AT THE SAAO (SUTHERLAND)

Explanation of the Weather Advisories Page

The weather advisories page provides information on severe weather conditions relevant to SALT operations. There are four advisories that may be issued.

1. "Low Pressure Event (high probability of high winds and precipitation)"

   This advisory is based on changes in air pressure within the forecast period. The pressure change between 0 and 24hrs, 6 and 30hrs, 12 and 36hrs, 18 and 42hrs after the initialization time is computed. The largest drop in pressure is identified and if the maximum pressure drop is greater than or equal to 5mb then an advisory is issued for the corresponding 24-hour period.

2. "High Wind Warning (winds stronger than 12m/s expected)"

   Using the forecasted wind speed, periods when the wind speed is forecasted to exceed 12m/s are identified and an advisory is issued for the corresponding periods.

3. "High Humidity Warning (high probability of condensation on cold surfaces or of precipitation)"

   Using the forecasted surface relative humidity, periods when the relative humidity exceeds 90% are identified and an advisory is issued for the corresponding periods.

4. "Snow advisory"

   Using the free air temperature and free air relative humidity, periods when the temperature is less than zero and the relative humidity is greater than 90% are identified and an advisory is issued for the corresponding periods.

Go to Today's Weather Advisory