Models have been suggesting that the middle of June (roughly June 10th-20th) would turn increasingly stormy and wet. The JMA led the charge several weeks ago with this idea. The GFS and it’s ensemble data has, for the most part, been on board with this line of thought, as well. On the flip side, more times than not, the powerful European forecast model has suggested we shouldn’t “hold our breath” on the prospects of a wetter shift. With the target period now only a few days out, it’s time to “put up or shut up.” I was chatting with a good friend of mine Tuesday evening concerning the recent dry conditions for the heart of central Indiana and that we’re heading into a “telling time” starting as early as this weekend. Should the wetter scenarios pan out I think it’ll be enough to keep the worst of the heat and droughty conditions west of Indiana for the balance of the summer. (Please know that’s not us saying it won’t turn dry at times, but instead just that the worst of the heat and dry conditions would be placed to our west).
While the all-important surface results differ, it’s encouraging to see that at least from the perspective of an upper air pattern standpoint, both models are rather similar. More significantly, this pattern would support rounds of thunderstorm complexes tracking southeast into the Ohio Valley this weekend and into early next week.
While impossible to nail down exactly which back yards would see beneficial rainfall, it would be an overall more conducive pattern for widespread showers and thunderstorms for our general region. We’ll have to lean on high resolution, shorter-term models as time draws closer to gain more insight around more precise timing and track details, but we continue to trend our forecast wetter Friday through Sunday than we’ve been over the past couple weeks- Alberto remnants excluded.
Come this time next week we’ll have a much better idea of where the balance of the summer is going, locally. Should beneficial rains fall, it’s still not too late in the season to have a significant longer term impact on summer as a whole. In fact, if we can get water in the ground, it would be easier to buy into the cooler regime the models are currently showing late-June. At the very least, an interesting weekend lies ahead…
Upper level energy will push east this afternoon and combine with an unstable air mass, along with unseasonably hot and humid air (highs today will reach the lower 90s across the southern half of the state with dew points around 70°), resulting in explosive thunderstorm development this evening. Storms will rumble east during the nighttime hours before exiting off to the east and diminishing during the early morning hours.
We target the time frame of 6p to midnight for greatest storm coverage and the possibility of severe weather. While the greatest threat of severe is just south of the city, itself, I think all of central IN is in play for the possibility of strong to severe thunderstorms tonight. In addition to locally heavy rain, stronger storms could pose a damaging straight line wind threat along with large hail.
Week 2
Weeks 3-4
The other big story, especially for those planning to attend the race, will be increasing humidity over the weekend. Forecast dew points will approach and exceed the 70° mark Sunday afternoon, providing a very tropical feel to the air.