INDOT Tech

Written by Ryan Dennis, valid for 1900Z.

Currently, there is a surface high pressure ridge pushing through the Midwest area which is bringing cold, dry stable air and no precipitation to Indiana. As seen by the RWIS observations, road conditions statewide are dry with road surface temperatures averaging around the low 50s even though air temperatures are below freezing.

As we continue through to tonight, the 2m temperatures are showing a steady drop as cold air is advecting south well into early Tuesday morning around 06Z. Coupled with a moderate vort max, some negative isentropic omega, and 700 mb relative humidity, it is possible to see statewide precipitation around this time which could also bring about road icing once the surface temperatures drop.

The GFS, NAM, and WRF are all in disagreement as to precipitation timing for 06Z Tuesday but the WRF and NAM suggest that mainly the central and northern portions of Indiana will be receiving no more than 1 inch of snowfall until around 09Z. Lake and Porter counties could receive more snowfall depending on lake effect since a northwesterly flow will be in effect at this time. Wind speeds should not reach up to more than 10-15 knots near the surface, however, this could still present a blowing snow hazard reducing visibility on the roads. Vincennes and Seymour districts have a lower probability of precipitation accumulation.

Once this possible system moves through tonight, the rest of the week up until Wednesday night seems quiet as cold temperatures persist with this continuing surface ridge.