A heavy, moisture laden storm system will start this coming week off very wet. Storm total precipitation will conservatively range from 1”-3.5” with coverage at 100%. We feel there can be a few areas with totals that exceed that upper range, but with so many other forecast outlets hyping this heavy rain so much, we want to offer a voice of reason…because honestly, what is the difference between 3.5” of rain in 3 days and 6 inches of rain in the same period? It’s how high the creeks, rivers and streams go…that’s all. It’s all just way too much rain anyway. So, we do look for stronger thunderstorms and severe weather cannot be ruled out. As hinted above with our rivers and streams comment…flooding is also a distinct possibility. The long and short of it is that we have too much rain coming in the next 3-4 days. Above is a map showing storm total precipitation through midnight Monday night. Impressive!
We do have a slightly drier outlook for the rest of the upcoming week in parts of the state. WE should be dry Tuesday and most of Wednesday statewide. Then showers develop over southern Indiana late Wednesday through Thursday. These showers will stay south of I-70 and will produce no more than .25”-.5” with 60-70% coverage south of I-70. The best rain potential will likely be south of US 50. There will be no rain up north. In fact, we see consecutive dry days from Tuesday through Sunday in the north. The one interruption Wednesday night and Thursday will be in in the south as well…so the intermediate forecast actually is not too bad. Problem is that we likely just get way to much rain this weekend for the good dry stretch to matter that much.
Temps will be rather cool at times this upcoming week as colder air funnels in behind this weekend’s system. However, we will not be as cold as what we are seeing in the plains this weekend. A couple of days this week we can have highs do no better than the lower 50s…but overnight lows should stay above freezing. Soil temps are in the 60s over most of the state….so while a few cold days will take temps down, we don’t think they will go below 50 degrees at the 4 inch level.
A strong high pressure dome centered over the Southeast US keeps IN/OH mostly dry for the 8th and 9th, to start the extended forecast period. During that time, moisture will be coming up the backside of the high, streaming across northern MO, IA, northern IL, WI/MN and MI. We are going to watch this closely: if that high pressure dome wobbles or moves east sooner, rains will easily come in to Indiana. But, for now, we expect a strong cold front to wait until the 10th-12th to move across the state. It will bring .5”-1.25” rains with 90% coverage.
Another strong low is likely toward the end of the extended period, around the 13th=14th, with rain totals of .5”-1.5” and coverage of 100%.
Weeks 3 & 4:
Even though we are continuing to call for some decent sized systems as we move toward mid-May, it should not be surprising. The rain totals we have in the extended period mentioned above are fairly close to normal. That pattern will continue into weeks 3 and 4. In week three, precipitation should be normal to slightly below over the state, and that may provide our best chance at a sizable field work window. The driest areas should be developing in SW Indiana. Temps that week do look cool, however, with below normal temps most of the period. For week 4, precipitation remains near normal, which means we should see another .25”-.75” of rain over the week, but system timing is way too far out to gauge. Temps should rebound back to near normal, or perhaps slightly below in spots. Still, week 4 will not likely be as cool as week 3.
This is a soil temperature map from last Thursday. Why post old data here?? Simple. What was going on last Thursday? We had just seen a strong front move through the Corn Belt. Temps in the northern plains had dipped into the lower 40s and 30 for a few days. Freezing temps were seen Thursday morning down into KS. Meanwhile, south flow had put temps on Wednesday up into the 80s over areas from eastern IL and Indiana eastward. What do you see on this map? Look at the sharp dividing line on soil temps? What we are getting at is this…with a bunch of rain to start this week’s planting forecast, and with the cold air temps coming in over the eastern corn belt as we mentioned above in our discussion…watch soil temps closely. Starting in the mid-60s means we can lose a lot of degrees and still be ok for planting…but the temps may not be as ideal in this upcoming week for germination of newly planted seeds as they were this past week.