Dry today over the state. We are behind a cold front that moved through last night and should see humidity levels drop somewhat. The front was disappointing, as it only triggered a few thunderstorms, mostly over the eastern part of the state.
Our Saturday rains do not look as impressive this morning, and at this time we are taking rain out of most of the state for tomorrow. WE can’t rule out showers and thunderstorms moving into west central and NW Indiana for afternoon and evening, but these rains only will end up affecting about 30% of the entire state. Models are in agreement on a drier Saturday at this time. Now, better chances of rain do exist for the state Sunday with a frontal boundary looking to sweep through the state. Still, these rains also do not look quite as impressive as they did earlier in the week. At this point, we are backing our rain totals down to 25”-.75” rain totals over about 70% of the state, and most of this action is tapering off by midday. We could be sunny by mid-afternoon and dry to finish the day. The above map is a snapshot of progression of the rain by midnight Saturday night, going into Sunday morning. This model suggests strong thunderstorms, giving the higher rain totals. But, we think those thunderstorms, or at least the strong thunderstorms, will end up being farther west, in IL.
Dry weather continues then for Monday and most of Tuesday. That’s the easy part. Then instability and uncertainty start to dominate later in the week, and those items are a key to our forecast this morning. Starting with Monday and Tuesday – high pressure will be in control and we feel this will start to build through the mid and upper levels of the atmosphere, allowing for an upper-level ridge to start to form. The ridge may stall in its development at midweek. WE have a few scattered showers that try to cross the state overnight Tuesday night and early Wednesday, amounting to a few hundredths to no more than .3”. Coverage will end up being around 70% of the state. Thursday is a tough call at this point. WE like a drier scenario but are troubled by moisture lingering over about half the state. Therefore, we will allow for some scattered showers through Thursday and limited sunshine. Rain totals will be .1”-.6” with coverage at 60% or less.
For Friday and Saturday, we have sunshine trying to re-assert itself, but we can’t rule out some isolated showers. This likely comes as a consequence of warming temps and higher humidity, triggering instability over the state. Action will not be in many places, the way we see it right now, but we can’t completely rule out these showers either. We will say that the northern half of the state has better chances and we can see 2-day rain totals of .25” to 1”, with the largest rain totals only possible with thunderstorms. If an upper level ridge does a better job of building through the week, and a tropical system does develop in the Gulf, making landfall sometime from midweek on (as we suspect), we think this forecast can get drier as the week wears on.
Dry next Sunday through Tuesday morning. We do have a cool front working in for the afternoon of the 27th (Tuesday) and crossing the state through the morning of the 28th (Wednesday). This front looks to trigger .25”-1” spots of rain with coverage at 70%. It may be followed up by another system on the 30th with .25”-.75” potential. Both of these systems are shown to be most aggressive on the GFS model, which has had a hard time with the extended period in recent weeks. Therefore, we look to see how the 10 day period ends and how strong of the ridge can form over the plains before really getting too excited about moisture in the extended window. We should be dry for July 1 and 2.