MAKING UP FOR LOST TIME...
A complex interaction of moisture and forcing remains in place across the Midwest that's ripe for showers and thunderstorms, some of which have already produced heavy rain (and for new ones with a similar threat all the way into Saturday). This has alleviated drought conditions in some areas and improved them in others. There's still work to be done but with the rain that's yet to come we are rapidly making up for lost time.
This is the latest drought monitor index. It doesn't look much different than last week but the primary reason behind that is the data was inputted Tuesday June 22nd, and the index released Thursday the 24th. Plenty of rain has fallen since then, especially in the central and south.
As I write this it's just past 1:00 AM (early Friday). Heavy rains are ongoing and appears that the area south of I-80, especially south of HWY 34 is going to see the largest overnight totals. A flash flood watch is in effect for that area through Saturday morning.
This is the excessive rainfall outlook from the Weather Prediction Center through 7:00 AM Friday morning. Places in southern Iowa and northern Missouri may end up with 4-7" totals by daybreak Friday.
This is the excessive rainfall outlook for Friday through Saturday morning at 7:00 AM. Notice it's further north encompassing the southern half of my area (roughly I-80 south).
This is the official WPC rainfall outlook through Sunday. There could be localized places in my far southern counties in Iowa near the Missouri border into WC Illinois that end up with total greater than 8" by Saturday night. Banding from training could produce exceptionally heavy swaths of rain and with the models smoothing the data it won't end up as evenly distributed as this graphic shows. It's becoming clearer that the heaviest rains and greatest threat for flash flooding through Saturday is likely to remain near or just south of I-80 with the greatest potential over the southern quarter of the region (HWY 34 south). Even so, most of the regions stands a good chance of seeing an additional 1-4 of rain Friday-Saturday with the south getting the lions share.
It also appears that with convective debris limiting heating and instability, the severe threat is likely to remain just south of my area Friday, maybe clipping far SE Iowa and WC Illinois Friday. Even there, torrential rain is a bigger concern than any gusty winds which would be the primary severe weather parameter.
Just to show you how tough it is for models to determine convective environments, here's some rainfall forecasts which all show varying degrees of placement with regards to the eventual heavy rain.
The 12K NAM
The 3K NAM
Precipitation should become more scattered on Saturday with lots of dry hours. Sunday in general looks to be dry, although clouds may linger with an isolated shower. Temperatures Friday-Sunday should stay in the upper 70s to low 80s, maybe a couple degrees cooler or warmer with a tad more or less cloud cover. Humidity will be a big factor Friday and Saturday but should back down a bit on Sunday.
That's where we stand heading into the weekend. Happy Friday everyone and roll weather...TS