textproduct: Des Moines

KEY MESSAGES

- Dry conditions continue through Today, with winds increasing out the south.

- Marginal Risk (level 1 out of 5) of severe weather for this evening and Thursday afternoon/evening.

- Rain/storm chances continue into Friday evening with the possibility of severe weather and heavy rain.

- Temperatures return to the upper 80's over the weekend.

SHORT TERM /THROUGH THURSDAY/

Issued at 218 AM CDT Wed Jun 3 2026

Clear skies were present on Tuesday and the same will continue for Today. High pressure that has been positioned over the Great Lakes will continue to keep us clear and dry Today.

The high pressure will eventually drift to the south. As the high drifts away, winds will eventually shift from the east southeast to more of a south wind. A tighter surface pressure gradient will begin to work into NW Iowa increasing our winds later this afternoon. The overall air profile will remain quite dry allowing for daytime deep mixing to occur. Wind gusts could reach up to 30 mph due to the deeper mixing. Due to the change in winds out of the south, temperatures and dew points will be on the rise which will lead to a more unstable airmass that will work into NW/Western Iowa. An incoming cold front will trigger showers and storms in central Nebraska and central South Dakota this afternoon. The storms will possibility continue to push eastward but will struggle to maintain their strength due to limited forcing and weak instability as they reach Iowa later tonight. Showers and storms look to stick around through Thursday afternoon, though not a complete wash out, rain chances will continue into the afternoon.

As we head into Thursday afternoon/evening hours, better instability looks to work into Northwest Iowa and parts of Central Iowa, which could lead to a few strong to severe storms. There is still uncertainly on how well we can destabilize from the morning convection, but if we can get clearing MUCAPE values could climb to over 1000+ J/kg which will be enough to support strong to severe storms. However, one factor that could limit organized severe convection is the marginal amount of deep layer shear. Guidance is hinting that deep layer shear will range from 25 to 35 kts. Due to the low amount of deep layer shear and decent instability, the Storm Prediction Center has placed NW Iowa and parts of Central Iowa in a marginal risk (level 1 of 5) with the primary concerns being damaging winds and large hail. These storms will have an ample amount of moisture to work with as PWAT's ranging from 1.5 to 1.6 which is near the 90th percentile of PWAT climatology for early June. This means that storms will be able to produce heavy rainfall which could lead to isolated localized flash flooding in a few spots. The Weather Prediction Center has placed NW and parts of Central Iowa in a marginal risk for excessive rainfall to highlight that risk.

LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/

Issued at 247 PM CDT Tue Jun 2 2026

The 500 mb ridge responsible for our dry mid-week conditions will be suppressed south and eastward by Thursday night, transitioning the upper level pattern over Iowa to more of a southwest to zonal flow pattern. This pattern will have keep persistent moisture advection up into the state Thursday night into Friday, leading to additional scattered shower and storm chances overnight. By Friday afternoon and evening, a shortwave will drop southeastward into Iowa, bringing additional synoptic forcing and a cool front. Showers and storms will develop along this boundary within a moist and unstable environment. Wind shear on Friday will once again be on the lower end, but with the boundary passage and upper level support, certainly can't rule out more strong to severe storms late Friday into the evening. Likewise, a high PWAT environment (1.6 to 1.7") will still be in place ahead of this boundary, resulting in another round of efficient and potentially widespread rainfall. Again, our dry spell should allow us to handle most of this, but rain falling in similar areas over multiple days could lead to some localized hydro concerns into the weekend.

Through Saturday and Sunday, a brief period of upper level ridging will bring warmer and somewhat drier conditions over Iowa, although shower and storm chances could still linger over the southern portions of the area. This reprieve looks fairly brief, as Sunday night into the beginning of next week could see another wet pattern develop.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1246 PM CDT Wed Jun 3 2026

VFR conditions are expected to remain across the terminals through the period. Breezy winds will remain through the afternoon, decreasing into the evening out of the south/southeast, before switching southwesterly late in the period and becoming breezy again. Some areas of cumulus will remain through the early evening, mainly west and north before dissipating. However, an increase in clouds is expected into Thursday in the mid-levels. A boundary passage into northwest Iowa after 06z will introduce low chances for some showers and perhaps a few storms, with chances included mainly at KFOD and KMCW at this time. Dry air further east lowers confidence elsewhere but will monitor trends and update accordingly.

DMX WATCHES/WARNINGS/ADVISORIES

None.