Yesterday: At 2130 – 0030 UTC, a large line of precipitation appeared on the radar. However, no precipitation was recorded at the Purdue University airport. Light snow was recorded in the northern regions of Indiana. Skew-t soundings for this this time, showed a dry air mass from the sfc to 850 mb.
The latest GFS model was fairly accurate showing small amounts of precipitation in the northern regions of Indiana while saying the West Lafayette would remain dry Thursday night.
Today/Tonight: Light snow is occurring in the area. This will continue tonight with more intense snowfall.
Using the Iowa State Meteogram Generator Figure 1 is showing the archived model data for KLAF. According to the models precipitation for our area was not expected, however areas in the northern portions of the state experienced some snow. For today and into Saturday models were showing snow accumulations around 1-3" starting Friday afternoon.
Figure 2: Radar 2202UTC 01/30/2014
Figure 2 ,however, shows precipitation over Lafayette for a time when the models said there would be no snow.
Figure 3: Model Skew-t 1800UTC 01/30/2014
Figure 3 is showing the GFS skew-t for around Lafayette at 1800UTC 01/30/14. There is a significant dry layer (850-500mb) between the surface and the moist layer, this was the cause of no precipitation at the surface.
Figure 4: Current radar image.