Past IEM Features tagged: sep09
The featured chart shows the GFS Model Output Statistics (MOS) value for probability of precipitation for Ames this month. Each bar represents a different model run's 36 hour forecast. The chart shows how small our rainfall chances have been this month, but Monday and Tuesday have the largest values seen this September. In fact, rain showers are currently in Western Iowa, so getting rain today looks to be a good bet.
The featured image is a wind rose for Ames for this month showing the complete lack of westerly winds and the overall lack of strong winds. Winds from the east and southeast are typically dry, so that helps to quell rainfall. This pattern looks to continue into the weekend.