Tracking two rounds of strong storms tomorrow

TONIGHT: Increasing clouds with lows in the upper 60s.

TOMORROW (Weather Alert Day): Two rounds of storms will impact the area with severe weather expected. The first round moves in by mid-morning and exits by around noon for areas along and north of I-70. The second round develops by late afternoon through late evening, bringing the potential for heavy rain, hail, and damaging winds. Highs reach the upper 70s to around 80 degrees.

EXTENDED FORECAST DISCUSSION: A complex of storms diving southeast across western Iowa and eastern Nebraska will enter the northern part of Missouri early tomorrow morning. Most of our current model guidance has this taking more of an easterly turn by morning and generally moving along I-70. If it slides a bit farther south, we could end up with heavy rain and isolated strong wind gusts for Jefferson City by late morning as well. Showers and storms move in after 6AM for our northwestern counties (Chariton/Saline/Randolph), and progress through the morning, eventually exiting to the east toward St. Louis by around noon.

A determining factor for afternoon re-development of severe storms will be how long this first round sticks around and if the atmosphere can properly recover as it exits. This complex of storms is expected to leave behind a remnant boundary that triggers more storms by late afternoon. Generally, the severe weather risk will be higher south of where these storms came through in the morning as the atmosphere will have had ample time to destabilize and won't have to recharge. The second round of storms is expected to start as discrete or single-celled storms which could point toward a brief tornado and large hail risk between about 4-7PM before storms begin to congeal into a line that pushes south through the evening. The threat would then transition to damaging winds in excess of 60-70 mph. Storms will exit between 10 PM-midnight and then our Weather Alert Day can expire. We'll also have to keep an eye on flood-prone areas as 1-2"+ of rain is expected across much of the area, especially in locations that are impacted by both rounds of storms.

Behind this system on Friday, we drop into the 60s with clearing skies. The weekend will start off unseasonably cool in the upper 60s with sunshine expected Saturday, and bump into the low 70s by Sunday. There could be a few showers on Monday, but the timing looks a bit later, so we could end up with a mostly rain-free holiday weekend. The active pattern returns next week with showers and storms possible Tuesday into Wednesday and warmer temperatures getting back into the mid-upper 70s.