WATCHING AN EARLY-WEEK HAIL THREAT

A highly-advertised stretch of warm and active weather is looking to move into the region this week with multiple systems capable of heavy rain and storms. While the bulk of the heaviest rain is shaping up to be east of our area, we still have some risk of rain and storms including some severe weather capable of hail starting Monday night. Analogs (above) are highlighting much of Iowa and northern Illinois for a risk of severe hail. Probabilities are already 50-60% for at least one severe hail threat.

High-resolution modeling is just getting in range for the event Monday night area are starting to show the scattered thunderstorm threat develop on the nose of warm air pushing into the area. These storms are developing generally after 7 p.m. and continuing through the overnight hours. Modeling right now indicated storms forming along and just west of the I-35 corridor before pushing east. This also appears to be mainly north of I-80 as of now, just clipping Des Moines to Dubuque.

This area is of lower certainty for now as we are still some time away from this developing.

The Storm Prediction Center already has a Level 1 of 5 risk, a Marginal Risk, for eastern Iowa and northern Illinois. This generally matches the modeling posted earlier along/east of I-35 and along/north of I-80. To reiterate, this is a Monday late evening and overnight event and a hail threat. A tornado threat is near-zero at this point in time.

Tuesday late afternoon and evening a second wave is looking likely, although this looks like a weaker system that will skim the area and stay more to the east.

Wednesday afternoon and evening another round of rain is likely to swing through the area however timing is different among our models. This looks like a higher chance to impact our area directly with some heavier, more beneficial, totals. One thing to watch Wednesday night into Thursday is the threat of colder air wrapping in on the back side of the precipitation that could actually lead to snow! We may not be 100% done with the white stuff yet, but I think the GFS is too strong with it. The Euro is slower and is more Thursday/Friday instead of Wednesday/Thursday.

THURSDAY MORNING - GFS

THURSDAY MORNING - EURO

The Euro is slower with the second system and is more Thursday/Thursday night. It still shows some light snow with the system but less of an accumulating threat. I think overall this makes more sense. The cold air the GFS tries to bring in seems excessive.

Through Thursday, official forecasts have most of our area in the 0.25-0.50" range with the heaviest staying just east/southeast. Locally heavier rain will be possible, especially depending on the scattered thunderstorm threat Monday night in eastern Iowa. Those storms alone could drop 0.50" to 1.00" and are not well analyzed in the forecast above. But with the Monday night/Tuesday and Wednesday night/Thursday events are more reflective above.

A second storm system is looming during the weekend time frame, but there are too many variables between now and then to get too detailed. With that said it looks like Saturday could be another rainy day in the region with yet another strong storm system. Once that passes we might have a break before some more action the following week as our active weather pattern continues through the first two weeks of April.

In terms of temperatures we will be quite warm Sunday through Tuesday before temperatures fall off midweek Wednesday/Thursday. Notice the lows Wednesday through Friday morning in the 30s - this could be cold enough for some snow potential with the active weather but overall the threat of accumulation is very low.

Longer term forecast highs will returns to near/above normal levels headed into the following week with highs in the 50s and 60s. April showers will be bringing those May flowers. Hopefully too, enough to bust some drought.

-Meteorologist Nick Stewart