What in the Weather?

[00:00:41] This day in Iowa weather history: The cold and snowy spring of 1907, linked to the eruption of the Ksudach volcano in eastern Russia [00:01:45] This week's forecast: A welcome break from active weather with temperatures reaching the 60s and 70s, mostly sunny skies, and high pressure taking hold [00:02:33] Frost advisory alert: Chances of frost Thursday and Friday nights, with lows near 32°F in northern Iowa [00:04:27] 8 to 14 day outlook (May 6–12): Below-normal temperatures and below-normal precipitation expected statewide [00:05:29] 3 to 4 week outlook (May 9–22): Continued below-normal temperatures; slight lean toward above-normal precipitation [00:06:09] Hazard watch: Slight risk of below-normal temperatures May 8–10, coinciding with the Mother's Day planting window [00:07:38] Last week's weather recap: Rainfall verified across Iowa, with some areas receiving over 2.5 inches [00:08:48] Severe weather recap: 10 tornado reports on April 23rd, primarily in western, south-central, and central Iowa, plus hail and high wind reports [00:10:21] Specialty crop planting recommendations for this week: Greens, carrots, beets, potatoes, brassicas, Swiss chard, fennel, and lettuce successions [00:11:08] Greenhouse starting tips: Lettuce and sweet corn successions; start melons now for post-May 10th transplanting [00:11:59] Pest updates: Imported cabbage worm confirmed; flea beetles still weeks away but currently emerged in central Missouri [00:12:40] Field management: Get cultivation done as soon as field surfaces dry out; begin tillage for future beds when further drying happens [00:12:53] Grower report — Garlic: Crop failure in unmulched beds linked to root rot (Fusarium?); mulched garlic faring well [00:14:26] Grower report — Onion thrips: Thrips found on black plastic mulch before transplanting, possibly harbored in nearby garlic plantings [00:15:41] Call for speakers: Seeking growers and researchers for the Organic Vegetable Production Conference and High Tunnel Short Course

What in the Weather: Iowa Weather and Specialty Crops Update - April 16, 2026 00:00:13 - Intro and This Day in Iowa Weather History: Iowa weather history from April 16, 1967, including an F3 tornado, large hail, fatalities, and historic dust storms the next day. 00:02:10 - Short-Term Forecast: Discussion of severe weather risks through Friday, followed by cooler weekend temps with freeze potential Saturday night, transitioning to sunny, quiet conditions next week. 00:04:02 - Extended Outlook: 8-14 day forecast shows near-normal temps and leaning wet; 3-4 week leans cooler/wetter; initial May outlook neutral, hinging on late April patterns like West Coast ridging. 00:05:44 - Wind and Recent Events: Confirmation of elevated winds April 16-20 (gusts to 30 mph Saturday), recent severe weather (hail dominant in eastern Iowa), tornadoes (11 in north, 5 in east), temp extremes (89°F high, 20°F low), and heavy rain (top-5 wettest April in parts). 00:12:09 - Specialty Crop Impacts: Wind damage reports (chicken tractors, center pivots); proactive field prep at Sun Dog Farm (plastic mulch, straw paths); advanced phenology (garlic, strawberries blooming); Cornucopia Farm tunnel recovery and expansions. 00:18:20 - Fruit Crops Update (Randall Vos): Area-specific bud stages (peaches/plums past bloom, pears full bloom, apples pink tip, grapes swelling); low freeze concern at 32-33°F but watch low spots; damage signs (black pistils, black centers); variety hardiness notes. Summary generated using perplexity.ai

Episode Summary: "What in the Weather" — April 2, 2026 00:27 – Iowa Weather History (1982): A dramatic cold front brought an 84–85°F high, then a 40°F temperature drop within an hour, followed by snow and blizzard conditions. 01:28 – This Week's Forecast: Two rounds of potential severe weather Thursday and Friday; rainfall 1–2½"+; followed by a weekend cool-down with frost and freeze potential. 03:09 – Discussion of how soil moisture affects overnight lows and frost levels across Iowa. 03:47 – Northwestern Iowa identified as driest region, likely to miss the heavier rains forecast for the east. 04:26 – Extended Outlook: Near-normal temps mid-April; wet pattern through at least the first half of the month; warmer, wetter signals toward late April. 06:33 – Recent Weather Recap: Monday night hail in central Iowa (Polk/Story Counties); vivid lightning; multiple rounds of rainfall from moving low-pressure systems. 08:15 – Dan describes seeing wavy cloud formations; Justin explains gravity waves caused by thunderstorms interacting with the tropopause. 10:26 – Temperature Extremes: Warmest—91°F in Clarinda; Coldest—10°F in Fayette. 11:04 – Specialty Crop Impacts: Early sweet corn planting underway; benefits of using plastic mulch for soil warmth. 13:19 – Fruit Crop Updates: Grapes at bud swell, plums blooming, pears at tight cluster—potential freeze risk; link to Michigan State's fruit freeze chart. 14:43 – Strawberry growers cautioned about freeze damage; row cover and sprinkler tips for small and large patches. 16:06 – Emerging Pest Alert: Lily leaf beetle —Have you seen it? 16:57 – Good Friday Potato Tradition: Historical planting custom versus agronomic timing; Dan's reflections on planting dates, frost tolerance, and pest cycles. 18:52 – Discussion of biodynamic planting calendars (Maria Thun and Stella Natura) and how lunar cycles are used by some to guide crop timing. episode summary generated using perplexity.ai

Episode Summary • [00:00:19] Welcome and introductions — Dan Fillius and Justin Glisan kick off the episode. • [00:00:40] On this day in Iowa weather history — a powerful 1954 storm brought dirty snow, sleet, freezing rain, and widespread damage to telephone and power lines across Iowa. • [00:01:19] Week ahead forecast — a winter storm system is expected this weekend with significant precipitation, especially in northeast Iowa, along with high winds and red flag warnings through Friday. Warmer and drier conditions are expected later in the month. • [00:04:02] Recent weather notables — much of Iowa has seen 170–400% of normal precipitation so far this month, with temperatures running about 14 degrees above average statewide. • [00:05:16] Severe weather recap — two severe weather events struck the region, including a tornado watch in central Iowa and a historic hail event near Kankakee, Illinois, where football-shaped hailstones measuring 6–8 inches were reported, potentially a new state record. • [00:10:26] Iowa's first tornadoes of the season — two tornadoes reported in Lee County in far southeastern Iowa caused minor damage. • [00:10:47] Specialty crop updates — Dan shares observations on overwintering crops including garlic, onions, kale, Salanova, and flowers, with notes on what survived the winter and what didn't. • [00:15:53] Nitrogen mineralization — an overview of Iowa State Extension's FACTS tool, showing how much nitrogen is mineralized across Iowa's climate divisions, when it peaks, and what it means for early-season crop fertility planning. • [00:19:23] Closing — no episode next week due to spring break; the show returns the last week of March. episode summary generated using Claude.ai

What in the Weather – Episode Summary Iowa Specialty Producers Conference | February 24, 2026 | Ankeny, Iowa This episode is a live recording of the What in the Weather podcast session presented at the Iowa Specialty Producers Conference. State Climatologist Justin Glisan and host Dan Fillius cover current weather conditions, a full 2025 weather year in review, and crop and pest impacts for Iowa specialty producers. Current Conditions & Outlook February 2025 has been one of the top five warmest on record; the state is now in a brief cool spell following a significant snowfall event near Waterloo (12–14 inches) Precipitation is at 72% of normal statewide, with northwestern Iowa below 50%; drought conditions are emerging and could worsen if dry weather continues The forecast for early March shows a warm and wet signal, which typically brings increased thunderstorm activity 2025 Weather Year in Review 2025 was the 25th warmest year on record (1.3°F above average); the past five years are the warmest five-year period on record June and July were exceptionally humid — dew points above 70°F were recorded on more than half of July's days, producing heat index values near 109°F The second wettest July on record was followed by a dry fall — Red Oak went 33 days without measurable precipitation Iowa recorded 36 tornadoes in 2025, below the average of 44, with no fatalities 2025 Weather Superlatives Coldest stretch: Feb. 10–22, with daytime highs as low as -20°F (NW Iowa) and a dew point of -29°F in Sioux County Warmest overnight low: 82°F in June (Quad Cities) Highest temperature: 101°F, Little Sioux (June 20) Coldest overnight low: -23°F, Fayette Biggest single rain event: 8.64 inches in Decorah Wettest location: Boone at 47.84 inches; driest: Randolph at 24.56 inches Longest growing season: southeastern Iowa; shortest: northwestern Iowa Crop Impacts Low winter precipitation in 2024–25 led to garlic winter damage on multiple farms Wet June and July caused widespread disease, delayed plantings, and poor early fruit set in tomatoes, peppers, and eggplant Worst-performing crops: onions (waterlogged soils), watermelons, and summer broccoli (heat and disease) Best-performing crop: tomatoes — scarce supply drove strong prices, with tunnel growers fetching ~$4/lb late in the season; late-planted fall carrots were a standout surprise Pest & Disease Highlights Top insect pests: aphids (especially damaging on fall and winter greens) and onion thrips Top diseases: pepper anthracnose, Alternaria on brassicas, and southern rust in corn Management tips discussed include pre-transplant aphid dips with M-Pede or Suffoil-X, interplanting sweet alyssum to attract beneficials, and a conventional onion thrips spray rotation using Movento and Radiant per the 2026 Midwest Veg Guide Podcast summary generated using Claude.ai

Podcast Summary Weather History & Current Conditions (December 18, 2025) Historic perspective: December 18, 1976 saw unseasonably warm temps reaching 64°F in Des Moines Recent pattern shift from active Alberta Clippers bringing light, fluffy snow to warmer, drier conditions Flash freeze warning for today as cold front passes through with potential snow squalls White Christmas Outlook Historical probabilities: Rock Rapids (70%), Des Moines (39%), Fort Madison (30%) 2025 forecast: Unlikely for white Christmas anywhere in Iowa due to warming trend and dry forecast through month's end Reflects broader trend of warming winters and transition from snow to rain/mixed precipitation Climate Forecast Next 7 days: Unseasonably warm (40s) and dry as polar vortex retreats north 6-14 day outlook: Strong signal for above-normal temps and dry conditions across western Iowa January-March: Equal chances on temperature, lean wet for eastern Iowa quarter Spring outlook: Potential transition to ENSO neutral conditions (70% probability), similar to pleasant spring 2025? December Snow Recap Fourth snowiest November on record for some stations Keokuk Lock and Dam (records since 1894) and Toledo (records since 1884) saw snowiest November-December period Multiple Alberta Clippers dropped 2-3 inches each, totaling 5-7 inches statewide December 14th storm caused I-80 closures and treacherous driving conditions Specialty Crop Updates Melcast System: Fungicide timing tool for melon growers will be available for Iowa locations (web-based platform from Indiana) Caterpillar Tunnels: Rolling Acres Produce Supply in Drakesville now manufacturing local tunnel kits with prefab end walls with doors Great Lakes Expo Recap: Major Midwest fruit/vegetable conference in Grand Rapids Annual Strawberry Production: New technique shared—rooting bare-root plants in plug trays for 6 weeks before July 15th planting optimizes yield and reduces runner management Upcoming Last episode of 2025 Live recording at Iowa Specialty Producers Conference, February 24th in Ankeny January episode will come, but unknown date right now. Podcast summary generated using claude.ai

Weather Forecast: Big winter cooldown coming this weekend with lows in the teens and highs in the upper 20s-low 30s Potential snowfall of 1-5 inches across northern Iowa Saturday into Sunday Temperatures warming back to the 50s early next week Leaning warmer and slightly wetter pattern continues in 8-14 day outlook (Nov 13-19) Historical Weather: Looking back at the November 6, 1990 snowstorm that brought up to 8.5 inches of snow and a record low of -1°F Recent Conditions: Six consecutive weeks of above-average temperatures ended with near-normal conditions at the end of October Western Iowa received a quarter of its monthly precipitation in just two days Fall foliage peaked with recent windy conditions Specialty Crop Impacts: Urgent: Harvest root crops (carrots, beets, radishes) before weekend freeze Protect lettuce with low tunnels; spinach and garlic can withstand cold Venting strategies for high and low tunnels to prevent moisture buildup and acclimate crops to cold Plant garlic now if you haven't already Tips on heating high tunnels for winter production Looking Ahead: The podcast moves to a monthly schedule for the winter with the next episode on Wednesday, December 3rd.

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, Dan Sheild, Brian Krug, and Natalie Hoidal summary generted using claude.ai

Weather History & Forecast: 1942: Early snowfall hit Iowa on this date, with up to 4 inches accumulating in some areas Coming week: Unseasonably warm and dry with sunny days, temperatures above normal Extended outlook: Strong warm signal through early October, particularly in upper Midwest Recent Weather: Past week: 8-12 degrees above average statewide First above-average rainfall period in weeks (with the highest, 4.54", in Fort Dodge!) Eastern Iowa remained drier than western areas Specialty Crop Updates: Peppers: Good yields continuing due to warm weather; some cyclamen/broad mite issues observed in Newton area Carmen peppers: Unusual spiciness reported - growers advised to check Melons: Reduced solar radiation from cloudy, wet summer conditions may have contributed to poor season (theory posited by Jordan Lyon, Buser's Produce) Tomatoes: Splitting issues due to uneven rainfall patterns Frost Outlook: No widespread frost expected through October 11th based on dew point forecasts Warm, dry conditions may still allow nighttime cooling near normal levels Upcoming Events: October 4: Nut Growers of Iowa field day (Centerville/Ottumwa) October 7: Shimek Forestry field day (southeast Iowa) October 9: Yellow River Forestry field day (northeast Iowa) Greenhouse/High Tunnel Tip: Control weeds now to prevent pest and disease carryover through winter Podcast Summary generated using claude.ai

Weather Forecast & Climate Updates • Hot and dry conditions ahead with temperatures in low-mid 90s and heat index values in mid-upper 90s • 8-14 day outlook shows continued warmth into late September with slight chance for above normal precipitation • ENSO update: 71% chance of La Niña transition October-December, signaling potential warm and dry fall/winter This Week's Weather Recap • Chilly temperatures that felt great after a hot summer • Mostly dry conditions with under 0.4 inches for most of the state • First freeze of season recorded at Stanley, Iowa (32°F on September 7th) Specialty Crop Impacts • Pumpkins: Strong auction prices ($5-10 vs typical $2-3) but poor growing season with fruit set issues • Cucumbers: Cold damage causing unmarketable scarring at Featherstone Farm • Melons: Season ended 6+ weeks early, creating H-2A labor contract challenges for growers • Watermelons: Poor year especially in low-lying areas due to fruit rot • Flowers: Mixed reports - Rose Farm had great year, others experienced delays • Honey production: Drastically reduced to 1/5 of expected yields, indicating widespread pollinator issues Historical Weather Note • September 11, 1917: Earliest freeze on record hit eastern Iowa with temperatures as low as 30°F, causing considerable damage to corn, potatoes, and other late crops Coming Next Week • Summer Glory Index results and fall foliage outlook Podcast summary generated using Claude.ai

Weather Forecast & Conditions: Cold front moving south from Minnesota will stall over Iowa, bringing rain chances Friday-Sunday Expected rainfall: up to 1-1.5 inches in northwest Iowa, less than 0.5 inches elsewhere Cool temperatures continuing into early September (50-60% chance of below normal temps) First overnight lows in the 40s recorded this past week Historical Weather Note: August 28, 1979: Violent F3-F4 tornado tracked 45 miles across southwestern Iowa, killing 2 people and causing millions in damage Growing Season Challenges: One grower called this "the worst growing season in recent memory" due to excessive rain and heat Watermelon season ending 1.5 months early due to persistent rainfall (14 inches over 2-3 weeks) Widespread crop diseases including Phytophthora on pumpkins, pepper anthracnose, bacterial spot, and southern rust on sweet corn Specialty Crop Impacts: Cut flower growers dealing with high soil pH (7.7) and nutrient leaching Recommendations to remove diseased peppers to prevent further spread Discussion of sprayer technology resources for disease management Looking Ahead: Hope for warm, dry fall to help struggling crops mature Next week will feature meteorological summer season review and in 2 weeks, the Summer Glory Index results Podcast summary generated using Claude.ai

Coming in September to your favorite podcast platform: Pivot Points, a new podcast exploring the stories of farmers who have made big changes to their farms and in their lives. Follow the Pivot Points podcast to make sure you get the podcasts as soon as they are released.

Main Topic: "Corn Sweat" Phenomenon Definition & Media Coverage "Corn sweat" is simply a catchy term for evapotranspiration Justin Glisan was interviewed by major news outlets (Washington Post, CNN, USA Today, CBS) The phenomenon was trending during the hottest week of July 2025 during a heat dome Scientific Reality Corn releases water vapor and oxygen through transpiration (not actually "sweating") Adds 3-5% to relative humidity locally (3-5 degrees to dew point) Peak evapotranspiration occurs during corn pollination/tasseling season Iowa has 13 million acres of corn contributing to this effect Comparative Analysis Prairie grasses actually have slightly higher evapotranspiration rates than corn Corn and soybeans have very similar ET rates during peak growth Historical prairie landscape would have different hydrology and soil structure Modeling is used to understand these complex comparisons since full-scale experiments aren't feasible Weather Forecasting History First tornado warning issued in 1940s by Miller and Fawbush at Air Force base WWII and 1946 weather radar development improved forecasting capabilities 1925 Tri-State tornado killed ~700 people despite warning signs, but no communication system existed Modern forecasting balances accuracy with avoiding "boy who cried wolf" scenario Social Media & Public Education Madelynn Wuestenberg urges people to stop sharing corn sweat TikToks Working on program to fact-check weather-related social media content Emphasizes need for agricultural meteorologists with both meteorology and agronomy backgrounds Summary generated by Claude.ai