Average August temperatures in Indianapolis feature highs falling from 84° to begin the month to 83° by months end, while average lows drop from 65° to 62°. We average 3.13″ of rain for the month as a whole.
There’s been a lot of chatter recently from local weather sources around how recent Augusts have run cooler than normal. Simply put, that’s not the case. Looking back to 2015, we’re running a clip of “every other year” running cooler than normal, locally.
As we look at August 2020 and the last month of meteorological summer, there are reasons to buy stock into cooler prospects, especially through the 1st half of the month. While there will likely be a rebound late month, it may not be enough to tip the scale towards the warmer side of normal.
Note the recent trends of the CFSv2. While never overly warm for our particular region, the model is expanding the cool for the month and pressing the relative warmth to the coasts.
Interestingly, the model is also developing a more consistent wet look.
The latest European Weeklies have a similar (but not identical) look:
The JMA is in the same boat, as well:
A positive PNA is anticipated to rule through the majority of the month:
The wild card, as is always the case this time of year, will be the tropics. There’s reason to buy into the idea (outlined in previous discussions and videos) that the “heart” of the season will be hyperactive and that begins during the month of August. Obviously, it’s impossible to talk landfall/ inland impacts, but those with interests to the GOM (Gulf of Mexico) and East Coast should closely monitor the tropics through the month, and for that matter, into the fall months.
Officially, we expect a much wetter than normal month across central Indiana along with average temperatures. The cooler than normal 1st half of the month will likely be met with moderation (compared to normal and in the means) late month to balance things out close to average. Our official August forecast is below.