A cold front is marching east across Minnesota, Iowa and Missouri late this afternoon. The front should pass through central Indiana early Sunday morning.
Ahead and along the front, a line of scattered showers and thunderstorms will be possible. Latest data suggests the line could cross the Illinois/Indiana state line around midnight.
Rain should reach the Indianapolis metro between 2am and 3am and move out of the CBS4 viewing area by 7am/8am Sunday.
At this time the threat for severe weather looks very limited. Latest forecast data from the Storm Prediction Center projects a 1% to 2% probability of severe thunderstorms along the Illinois/Indiana state line from 11pm Saturday through 2am Sunday.
That is where the threat for severe thunderstorms peaks. After 2am the probability quickly diminishes to less than 1%.
POST FROPA (FRONTAL PASSAGE)
Once the front passes, drier air will begin to filter in to the state.
The dew point temperature – the measure of the moisture in the air – has been in the lower to middle 60°s today. When the dew point temperature reaches 60° it starts to feel uncomfortable. Above 65° it feels “muggly”.
The good news is that computer models project dew point temperatures will drop to the upper 50°s Sunday and lower to middle 50°s Monday. This will make the air very comfortable.
Unfortunately, the comfortable air won’t stay around long. Temperatures will begin to move back to the middle and upper 80°s.
We are keeping an eye on the upper-levels of the atmosphere late in the week. Long range data suggests a “hot dome” developing over the Red River and Mississippi River valleys. This could set us up for a “Ring of Fire” pattern when thunderstorm complexes develop late night around the bubble of hot air. Then the thunderstorms slide down the northeast side of the “hot dome”.
The first time that could happen would be Friday morning. A second time looks to happen late Friday night through Saturday. Stay tuned!