Iowa 7-Day Forecast: Highs Hold in the Low-to-Mid 80s Through Early June

What changed

Today (Wednesday, May 28) is the warmest day in the outlook, with a forecast high of 88°F. After that, daytime highs ease back a few degrees and settle into a narrow band:

| Day | High (°F) | Low (°F) | |---|---|---| | Wed 5/28 | 88 | 64 | | Fri 5/29 | 82 | 63 | | Sat 5/30 | 81 | 63 | | Sun 5/31 | 83 | 63 | | Mon 6/1 | 84 | 62 | | Tue 6/2 | 84 | 61 | | Wed 6/3 | 83 | 62 |

Overnight lows stay in a tight 61–64°F range all week.

Why it matters

Temperatures in the low-to-mid 80s with lows above 60°F keep growing degree day accumulation moving at a good clip for corn and soybeans at this stage. The consistency matters — no late-season cold snaps and no extreme heat spikes in this window. That kind of even warmth could support steady early-season crop development across central Iowa.

What to watch next

• Whether rainfall accompanies this warm pattern — temperature alone doesn't tell the full moisture story. Check your local NWS office for precipitation outlooks.
• Any shifts in the extended forecast beyond June 4 that could bring heat stress or cooler air.
• Growing degree day totals for your area — your county Extension office or local mesonet can help track those.

Source notes

All temperature data from the U.S. National Weather Service API (Des Moines/Johnston, IA grid point). Forecast issued for the period May 28 – June 4, 2026.