10/16/25 - Widespread frost not likely until November

Weather History & Current Conditions

• Historical note: In 1950, Des Moines saw a 14° temperature spike in 5 minutes during a thunderstorm, reaching 87° due to prefrontal warming
• Current forecast: Cold front Friday with showers/thunderstorms, then cooler temps - returning to seasonal averages (mid-60s highs, upper-40s lows)

Frost Watch

• Only 5 Iowa stations have hit freezing so far (Elkader, Sioux Center at 31°, Stanley, Spencer and Mason City at 32°)
• No widespread frost or freeze expected through end of October
• Growers advised to protect tender crops like basil during low-40s temperatures

Precipitation & Long-Range Outlook

• Southwestern Iowa received 3 inches of rain (nearly a month's worth)
• Winter outlook shows classic La Niña pattern: leaning cold in northwest Iowa, wet in eastern Iowa for December-February
• Warmth persisting through end of October with near-normal precipitation

Specialty Crop Updates

• Root crop harvest underway
• Spinach showing Cladosporium (fungal disease) in high tunnels—venting recommended
• Resources shared: eGRO water testing guide, corn earworm management in cut flowers

Upcoming Events

• Albert Lea Seed cover crop show next Friday in Ames
• High tunnel short course November 12th at Iowa Arboretum featuring Becca Rudebusch

summary generted using claude.ai