IEM Daily Feature
Friday, 03 February 2012

Heavy snow, rain, or nothing?

Posted: 03 Feb 2012 06:04 AM


View larger image
white color is no forecast (outside of model time bounds), pink is near zero or zero
Winter is expected to return this weekend with a storm system developing just to our southwest this morning. The weather forecast models have been teasing a significant snowfall for Iowa, but change their mind after sequential runs in time. The featured chart presents Global Forecast System (GFS) model forecasted precipitation for a grid point near Des Moines. The model is run every six hours producing a forecast out for the next two weeks or so. Model runs up until January 30th had this weekend being dry. Subsequent model runs then dumped heavy amounts of rain or snow or some mixture for Des Moines. Two model runs yesterday had Des Moines missing almost all precipitation. The most recent run (top row) now has rain today and snow on Saturday. Model inconsistencies like this make life fun and the folks that forecast the weather for a living lose hair or grey quickly.

Voting:
Good = 21
Bad = 4

Tags:   model