Iowa Weather History:
On June 19, 1996, severe thunderstorms produced very large hail in northwest Iowa, with a 3.5-inch stone near Hinton (Plymouth County) and a 4.5-inch stone at Cushing (Woodbury County), causing $200,000 in damage to vehicles and buildings.
7-Day Weather Forecast:
Iowa is entering a "blast furnace" pattern: temperatures will soar 15–20°F above average, with highs in the 90s to upper 90s and overnight lows in the mid to upper 70s.
Persistent high overnight lows will make it difficult for people and plants to recover.
Strong southwesterly winds will continue, bringing high dew points and Gulf moisture.
By days 4–6 (early next week), the northwestern two-thirds of Iowa could see 2–5 inches of rain, especially in western Iowa, which needs relief from drought.
Climate Outlook:
The 6–10 day forecast shows the heat shifting east, with a tighter temperature gradient and continued potential for heavy rainfall, especially in northern Iowa.
The 8–14 day outlook keeps a warm and wet signal, which is positive for the wettest month of the year after recent dryness.
The 3–4 week outlook still leans warm, with no clear signal on rainfall.
The initial July outlook (issued June 19) leans slightly warm statewide, with a slight lean dry in the western third of Iowa.
Recent Weather and Notables:
The past week was slightly warmer than average with an unsettled pattern of pulse and "popcorn" thunderstorms across the state.
Severe weather ingredients did not come together for widespread severe storms, but there was a landspout tornado in eastern Iowa.
Landspouts are weaker, photogenic tornadoes (a step above dust devils), typically anticyclonic, and distinct from stronger tornadoes.
Specialty Crop Impacts:
Hot weather is negatively affecting broccoli development, leading to issues like "brown bead" (brown florets) and heat-delayed buds.
Brown bead can be caused by hot, humid nights; broccolini is less susceptible and can regrow after harvest.
Hollow stem in broccoli may result from fast growth due to excess nitrogen and water, not just boron deficiency. Tighter in-row spacing and careful nitrogen management can reduce hollow stem.
Boron deficiency causes brown, dead cells lining the hollow stem, while fast growth causes uniformly green or white hollows.
Boron should be mixed with other powders for uniform soil application to avoid toxicity.
Some broccoli varieties (e.g., Green Magic) are more prone to hollow stem than newer ones (e.g., Eastern Crown).
Heat can also cause uneven, lighter green patches in broccoli heads (heat-delayed buds).
Brown bead does not grow out, but heat-delayed buds sometimes do
Cabbage White butterflies and their caterpillars are active.
BT (Bacillus thuringiensis) sprays are effective when caterpillars are first seen, especially on new growth and broccoli heads.
Rotate BT with other organic insecticides if resistance is suspected.
Cabbage moth caterpillars can hide inside broccoli heads, making washing difficult.
Summary created using Perplexity.ai
