Area Forecast Discussion

KEY MESSAGES

- Warming trend throughout this week with highs likely in the 70s for most south of I-94 by Tuesday.

- Showers and storms likely (60-85% chance) for Thursday evening and overnight, confidence for strong to severe storms is low at this point.

DISCUSSION

Issued at 1145 PM CDT Sun Apr 19 2026

Today - Wednesday: Dry with a Warming Trend

Surface high pressure will be the name of the game today as southerly surface flow builds in aiding in bringing a warmer airmass into the region. As a result, highs today will trend a bit warmer with temperatures reaching into the 50s for most locations. As we head into Tuesday and Wednesday, upper-level ridging will push into the local area further cementing this warmer airmass into the area with NBM inter-quartile spread reaching into the upper 60s to middle 70s. Overall with fairly robust subsidence underneath both this upper-level ridge and surface high from Monday through Wednesday, this should keep any precipitation chances to a minimum.

Thursday - Friday: Showers and Storms Likely Thursday Evening

The pattern then changes a bit as we head into Thursday with a fairly amplified upper-level shortwave trough pushing into the Northern Plains on Thursday with a rapidly deepening surface low and cold front associated with it. As a result, most of guidance generally agrees on pushing the cold front through the local area during the evening and into the overnight for Thursday. Currently, both shear and instability are not overly impressive with the GEFS/GEPS only having 20-40% probabilities for over 1000 J/kg SBCAPE west of the Mississippi River. With initiation likely occurring west of the local area and 0-6km bulk shear only being around 25 kts in the deterministic GFS, would expect a linear progression into the area along the front with minimal instability keeping updrafts fairly weak. As a result, confidence in severe potential is not overly high, however still cannot be ruled out with the ML/AI guidance painting some 15% probs west of the Mississippi River where you might have a slightly more favorably oriented 0-3km shear vector and slightly higher instability earlier in the evening. Regardless, with the passage of the cold front, cooler temperatures would make their way in for Friday with highs generally being in the 50s to 60s.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 533 AM CDT Mon Apr 20 2026

VFR conditions expected for the next 24 hours at the terminals. Southerly winds will continue to increase over the coming hours with sustained speeds between 10-20 kts by this afternoon. Some gusts to around 25-30 kts will be possible, mainly across Southeast Minnesota and Northeast Iowa. Gusts will taper off by the evening with sustained speeds on a gradual decline through the overnight hours.

HYDROLOGY

Issued at 1145 PM CDT Sun Apr 19 2026

Flooding continues along the Wisconsin and Yellow rivers where the river stage is in Minor Flood at both Necedah, WI and Muscoda, WI. This is expected to fall below flood stage by mid-week with no precipitation expected through Wednesday. The Flood Watch at McGregor on the Mississippi River has been cancelled as upstream flow in the Wisconsin River has trended less than previously forecast, as a result this site will likely not reach into flood stage.

ARX WATCHES / WARNINGS / ADVISORIES

WI...None. MN...None. IA...None.