The dog days of August never showed up this year. Those hazy hot humid days the month is known for have been few and far between. The hottest day so far this August in Cedar Rapids has been 87 and that was way back on the 4th. We've now gone 8 consecutive days without an 80 degree high. You can see the August 2019 temperature departures and the dominance of cool air in the central U.S.
The streak of 8 days without an 80 should come to an end Thursday as a quick surge of warm air surges northward ahead of a cold front. Most of my area should end up with highs in the low to mid 80s. The EURO shows this.
The southerly winds that bring the warmth will also draw in some moisture. Dew points should get into the upper 60s before the front arrives.
That looks to be enough to drive some decent instability for the cold front to work on. Here's the CAPE (convective available potential energy) for storms.
The Storm Prediction Center has a slight risk outlook in place for severe weather Thursday afternoon or evening. The greatest chance is expected over the SE half of my area.
Shear looks relatively weak so tornado chances are low. However, some robust updrafts are possible at peak heating that could trigger scattered wind and hail. It doesn't appear that severe weather will be widespread at this point. There could be some heavy downpours though where the stronger storms are found. This is the line of storms as it goes linear around 6:00pm on the 3k NAM.
Once the front departs Thursday evening so do any rain chances through Friday. However, there is still concern that the front stalls and remains close enough Saturday for a wave of energy to generate a cool over-running rain event.
The latest trends have been to push this a bit further south which I was anticipating in my last post. The EURO really went rogue since yesterday and just clips my far southern counties with its significant rain.
The GFS as you can see is further north.
The Weather Prediction Center is more in line with the GFS
I would expect models to converge on a solution soon. However the rain situation turns out, I'm expecting plenty of clouds, east winds, and well below normal temperatures Saturday. It's still possible highs may struggle to get much above 60, especially where rains are more widespread.
After that things improve dramatically for the rest of the holiday weekend with highs Sunday and Monday 75 to 80 under partly to mostly sunny skies. 2 out of 3 good days, hard to complain about that! Roll weather...TS