The following content was provided by meteorologist David Tolleris of WxRisk.com:
A quick look at the national radar can be seen here.
The early morning national radar does not show a lot of activity. There is a cluster of thunderstorms over northwest Missouri which extends into southwestern Iowa and some storms over southeastern Kansas and northeast Oklahoma and a small cluster of thunderstorms over central South Dakota. In addition there are several weak areas of scattered showers across the lower Midwest --southern Illinois, Indiana and western Kentucky.
This is going to be another drier week -- in fact the pattern looks drier for the next 10 days. There will be several different cold fronts which will pass through the Midwest over the next 7 to 10 days but none of them show any sort of significant shower thunderstorm activity with their passage. In the 6 to 10 day the European and the GFS show anomalies of 25% to 50% of normal rainfall over the eastern Corn Belt (ECB), while the Upper Plains sees close to normal rains and the western Corn Belt (WCB) sees 75% of normal rainfall. Hurricane IRENE will NOT bring significant or even moderate rain to any portion of the ECB.
The morning weather map shows HIGH pressure covering the upper Midwest and the Great Lakes and there is a front separating this cooler air mass from the heat over the lower Plains and the Deep South. This front runs from west to east across the central Plains and the Midwest. It is this front which is causing the showers and thunderstorms we see over portions of southern Iowa and Missouri and the lower Midwest We have a massive heat dome that is centered over the four corners region of the western third of the CONUS. This feature is so large that it extends into western Canada and it is altering the jet stream in such a way that when two cold fronts try and come south through the Upper Plains and Great Lakes this week... they are sweeping through these regions with a different trajectory than they normally might.
As a result the next few cold fronts don't have the moisture work with and they end up not producing a lot of showers and thunderstorms. The first cold front moves through AUG 23-24 and will bring scattered showers and thunderstorms to Midwest but the coverage only appears to be around 50% and the amounts look pretty average 0.25 to 1.00".
The temperatures will continue to run quite hot even for late August across much of the Central and Lower Plains as well as the Deep South with many areas seeing temperatures at or above 100° but this heat does not really get into the upper Plains and the Midwest regions at all over the next two weeks.
This coming weekend the looks like hurricane Irene will make a very close approach to the southeastern U.S. probably making landfall neither South Carolina and/or North Carolina. This will be a major rain event for the southeast coastal areas and into the middle antigen New England but it will not bring any significant rain to any portion of the Delta or the ECB.
The weather models are developing a stronger system which comes out of the northern Rockies into the Upper Plains the Midwest this weekend which develop significant showers and thunderstorms to ND SD NEB MN WI ILL IA .... right nwo this looks to be a 50-60% event of 0.25 to 1.00".
In the 11 to 15 day, the forecast is highly dependent upon what happens with IRENE. If she moves up the East Coast she will probably merge with another system over southeastern Canada. That may bring down a brief cool air mass for day or two but the model data shows a new fairly strong ridge developing over a good portion the central and Lower Plains the Deep South and the the Midwest in the first week of September.. .so temperatures should continue to run above normal and rainfall below normal.