Good afternoon everyone! This update provides 18z high-resolution model runs in regards to precipitation over the next couple of days. Numerous shower/storm activity has filled in across portions of KS, southwestern MO, and southeast NE as of 4:25pm CDT. The culprit for this convection is an upper-level low lifting northward from the Southern Plains providing sufficient forcing for the development of widespread showers and storms. While coverage will fluctuate at times into mid-week, rain chances will remain across a large majority of the area through the period.
Here’s a look at the NAM3km simulated radar through 7am CDT Tuesday morning: Widespread showers/storms will continue to lift north and eastward across a large chunk of KS (less coverage across far western KS) through the remainder of the evening, spreading into other portions of southern NE over the next few hours and west-central/south-central MO this evening into the overnight hours. By 7am CDT, shower/storm activity will continue to work northeast with more coverage likely across southeast NE and western/central MO. A few showers may begin to push into far southwest IA at this time. While severe weather remains unlikely, I can’t rule out gusty winds and small hail accompanying some storms.
The storms this evening through tonight possess a heavy rain threat given the high moisture content in the atmosphere. The WPC gives central/eastern KS and southwest MO a slight risk for flash flooding through tonight. This threat will shift slightly further east Tuesday and Tuesday night where a slight risk for flash flooding exists for southeast KS into western MO Tuesday.
As mentioned above, storm coverage will shift slightly eastward heading into Tuesday. This slow-moving storm system will continue to bring more rain across KS (mainly the eastern 2/3rds), with rains lifting northeast across the state of MO and eastern NE throughout the day. Additional storm development is likely in the afternoon across eastern KS and western MO where the heaviest storms appear to be concentrated. Shower/storm coverage will also build across southern IA during the morning hours Tuesday before lesser coverage spreads into the eastern and northern portions of the state during the evening and overnight hours. The amount of rain coverage is still questionable across IA at this time, but it is worthy to note that this model run trended wetter for southern IA. Isolated storms are possible across the Western Plains Tuesday afternoon/evening. Another disturbance off to our northwest will dive into northwest NE overnight Tuesday into Wednesday morning, bringing increased storm chances. Some storms may produce small hail and gusty winds. A simulated radar from 7am CDT Tuesday through 7am CDT Wednesday is shown below.
Here’s a look at total rainfall through 7am CDT Wednesday: While not mentioned below, southern IA may have a few pockets of 1-2″ of rain from scattered storms lifting into the area. Localized pockets of 0.5-1″+ are also possible in northeast NE and far northwest IA.
If you have any questions do not hesitate to reach out! Have a great evening!