Get ready for a longer video today. I will cover all the of the heavy rain/severe t-storm threats as well as some of the new data to get us into the end of September.
For this written post, I will at least type out what to expect with our first system that will challenge us this week.
Arrives tomorrow morning...roughly in the 4-8am window...west to east. This is not a strong warm front. Which is normal--as strong warm fronts are rare in the summer. But there will be enough of a push of higher moisture into the area to lead to a broken line of downpours and even a few thunderstorms. I am not concerned about severe weather with this passage, but the downpours will need to be watched for timing. With JCPS and others back in play, a heavy downpour at say 6:30am would be a complete mess. So let's hope these are spaced out and/or the front times out slower and misses the core of the AM rush. Which is still possible. Again, not a huge event...but timing could be a pain.
We will be fully in the "warm sector" of this system by Wednesday afternoon, but coverage of thunderstorms looks more scattered. A few could be locally strong/heavy but many spots will get missed. It will become more humid.
LOW PRESSURE/COLD FRONT
The main low will pass from IL into northern IN Thursday. The cold front attached will sloooooowly work its way east into WAVE Country during the day. My concern with this time period if two fold. There is a decent mid level jet of wind early in the day to allow for a band of locally heavy rain. So yes, the AM rush could get impacted again if that is the case. The second is that areas along/east of I-65 could heat up enough for some stronger thunderstorms in the afternoon. That second factor is one that is more iffy as it will highly depend on the amount of heating/fuel that can be built up. We won't know that answer until Thursday morning. So this is a threat that could go up or down in scale. For both issues that day, I did upgrade to an Alert Day for impacts. With many schools back in session and the start of the KY State Fair, a bigger "heads up" is the idea there.
The cold front mentioned above will slowly push south and become horizontal on the map. There is another wave of energy that wants to roll in Friday night that could enhance the rain/thunder into early Saturday for areas along/south of I-64. Otherwise, the rain chance should start to slowly build south with the front. It may take until Sunday to really knock down the rain coverage for most areas.
IT WON'T LAST LONG
Another system (stronger) will likely move in early next week. This one looks to really shake things up for us. At least briefly. This one is covered more in today's video.