We have been studying weather for a couple of weeks now. This week our nature study challenge suggests to "share with your children this week about what influences the temperature and the atmosphere around us." Today we looked at the influences of air pressure. High pressure systems are places in the troposphere where more air is piled on the earth's surface. Likewise a low pressure area is where the atmosphere is thinner. Air pressure can be measured with a barometer. A barometer is commonly used for weather prediction, as high air pressure in a region indicates fair weather while low pressure indicates that storms are more likely. When used in combination with wind observations, reasonable short term forecasts can be made. We looked at our barometer and discussed the correlation between the number of the pressure and what this could mean. We looked at the weather chart we have been keeping for the last couple of weeks (our cloud blog entries) for patterns. We noticed that when the wind began blowing from the south, rather than the north, rain appeared soon after. This cannot be a strong predictor as we are only looking at a small time period, but if this pattern keeps for months, it could be considered a indicator. We will keep an eye out for this when we study weather again in another season. They also related that the clouds became puffier right before a rainy day. I encouraged them to continue these observations when we go on our nature walks and to include sometimes notes about the weather on their journal pages.