Hail which produces ice grains with a relatively large size can be seen from the signs of changes in weather parameters on the surface such as temperature and air pressure. To be able analyzing the occurrence of hail in territorial Karo, analysis of temperature, air pressure, satellite image, streamline and sea surface temperature are conducted. Temperature and air pressure analysis through time series graphs can see patterns of change as an indication prior until the occurrence of hail. Analysis of satellite imagery is made to representate a cloud image which shows the development stage of Cumulonimbus cloud that caused hail and representate the increase in water vapor. Analysis of sea surface temperature is made to see the supporting factors and streamline analysis is created to see wind patterns that cause convection activity. The results of the temperature analysis obtains a significant increase while the air pressure analysis results a significant decrease. The result of satellite imagery obtains growth stage of Cumulonimbus cloud and the increases of cloud peak temperature and moisture content. Whereas, sea surface temperature analysis shows that Indian Ocean and Malacca Strait are warm and streamline analysis shows the sharp turns gather in the southwest.

Keywords : Hail, Temperature, Pressure, Cumulonimbus, Streamline