ACTIVE, WARMER WEATHER TO END SEPTEMBER

Hello friends, Meteorologist Nick Stewart here once again today with a weather update. The good news today is that the noticeable trend towards a rainier, more active end to September appears to be holding in Friday's model runs which continues to be a good sign across a drought-stricken corn belt. I do think it's worth explaining what exactly "above normal" may mean for the region.

Let's start off with how the analogs look for late September: It's a pretty obvious look with above-normal temperatures and above-normal precipitation. This overall continues to look like a favorable early-autumn storm system as the "second season" ramps up. This can bring some severe weather to the region as well but those details are a long way from being figured out. Let's focus on the pattern first.

Let's frame exactly what "normal" is in terms of precipitation this time of year. I'm still focused mainly on the period Sept. 21-29. In Cedar Rapids, Iowa, the average precipitation through that period is just shy of 1.0". So as we talk about "above-normal precipitation," that's the benchmark we are primarily looking at.

So let's look at some model data. Above is the 7-day precipitation anomaly ending Sept. 27 based off the European Ensemble. There remains a large plume of above-normal precipitation across a significant section of the United States. While at this range the exact values are not as useful as it's a heavily averaged number from 50-different forecasts, however let's take a peak just for context.

In Eastern Iowa, much of the area is sitting up to 0.4" above normal. So, using our context of "normal" being 0.96", that would be about 1.4" of precipitation over that week period. To reiterate, this is not a forecast yet but I did want to show you what this could, in theory, mean in terms of total rainfall.

Analogs are hinting at a 30-40% chance of at least 1.0" of precipitation Sept. 23-36. At this range, that's a pretty high-confidence forecast.

To lend some support to my forecast the last two days, the Climate Prediction Center introduced a risk of heavy rainfall across the central US. A good signal for beneficial rainfall. We will keep a close eye on things!

Meanwhile here in Florida, the active launch cadence continues. Another SpaceX Falcon 9 launch is scheduled for Friday night after a weather-related scrub Thursday night. SpaceX lands their rockets on a barge in the Atlantic Ocean to be reused. Hurricane Lee continues to cause large waves over 10' which is hampering rocket recovery operations. Hopefully we can get this bird out of here tonight but I'm not too optimistic. We shall see.

-Meteorologist Nick Stewart