It is more likely for an area with higher atmospheric pressure to be sunny. In the same way, it is more probable in low-pressure areas for it to rain.
This is because of the law which states $pV=(c)T$ where $p$ is pressure, $V$ is volume, $T$ is temperature and $(c)$ is a constant value, for the same $T$ temperature, lowering pressure $p$ should lead to increase volume of the gas (air in this example).
Ant vice versa: lowering volume $V$ leads to an increase in pressure $p$. The gas should be guided to condensation and the rain.
So using this basic formula high pressure area should be more likely to cause rain.
Where am I thinking wrong? Are there too many simplifications?