STEAM AND STORMS, THE NAME OF THE GAME...


Sunday night's storms (MCS-mesoscale convective system) pounded a wide swath of my local area with winds of 30-60 mph and locally heavy rains. You can see in the rainfall plot the region impacted.

Here's some of the specific rainfall totals from my region. I had nearly 2.00" at my ranch in Marion.

Unfortunately much of the rain fell where it was needed the least. In the graphic below you can see a corridor from NW to SE across Iowa where rains the last 3 weeks have amounted to less than 1/2". Some of the driest areas are near Ames and Sioux City.

The lack of rainfall has been prolonged enough for parts of Iowa (especially the south) to now be included in abnormally dry to moderate drought conditions.

Here's a larger perspective of the Midwest as a whole.

Last July, the rains were generous over much of Iowa. Only the NW and a small part of SC Iowa suffered from dry conditions.

Going forward, the control run of the EURO weeklies shows the region from central Iowa through the central and southern Plains remaining dry the remainder of summer. Here's its 46 day rainfall forecast ending August 25th. Normal rain for the period in my area would be about 7".

By the way, the dew point in Cedar Rapids hit 78 Monday and reached 80 in Burlington. The high moisture levels (thanks in part to evapotranspiration from maturing corn plants) will make conditions very uncomfortable for at least a couple more days. At this point Wednesday appears to be the worst. The GFS has dew points near 80 in SE Iowa and WC Illinois.

Heat index values should hit or exceed 100 unless clouds or convection can help us out. If not some areas will likely meet heat advisory thresholds in the afternoon.

Thunderstorms are also not out of the question with so much available energy. Models are struggling a bit to pinpoint timing and location but the ring of fire is alive and well and some parts of the Midwest will see strong storms and heavy rain in the coming 48 hours.

While a few storms are possible during the day Tuesday, it's Tuesday night when the next MCS is projected to roll southeast. This could bring strong storms and more heavy rain wherever it develops. The 3K NAM is bullish on this scenario developing storms in Minnesota and then driving them south across Iowa at night. Here is the simulated radar at 3:00am showing a mature MCS.

The Storm Prediction Center has an enhanced risk in place for Minnesota where the storms initiate. It could be extended further into Iowa if the 3k NAM is right.

Steam and occasional storms. that's the name of the game the next few days. Roll weather...TS

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