What in the Weather?

00:25 — Iowa weather history: An October 1996 storm brings heavy rain and early-season snow.

01:18 — Weekly forecast: Rain favors northwest Iowa as temperatures ease

02:52 — Extended outlook: Warmth remains favored into November, with El Niño and jet-stream placement shaping precipitation chances.

06:49 — Winter weather discussion: How the quasi-biennial oscillation (QBO) could influence polar vortex outbreaks— *analog years aren't a forecast.

10:46 — Weekly recap: Widespread rain, above-average temperatures, and a late frost bring mixed consequences for growers.

12:12 — Agritourism and pumpkin losses: Wet fall weather hurts farm visits and contributes to widespread fruit rot.

13:50 — September rainfall rankings: Why record-setting totals at individual stations can differ from climate-division averages.

16:44 — Weekly weather extremes: Iowa's hottest, coldest, wettest, and driest reporting locations.

17:14 — What makes weather "comfortable"? Comparing Iowa with coastal California, revisiting earthquake memories, and finding Iowa's nicest seasonal weather windows.

24:47 — Horticulture Friday's anniversary and an introduction to pumpkin grower Beany Bode's fall update.

27:51 — Specialty crop reports: Lingering dryness in Kossuth County, later high-tunnel planting dates, broccoli disease losses, and a challenging growing season.

30:26 — Looking ahead for strawberries, followed by an unresolved butternut squash discoloration question.

31:43 — Closing perspective: Why it's too early to trust weather predictions for next growing season.

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00:07–01:47 — Justin recounts the historic October 15–16, 1880 Iowa blizzard, including severe thunderstorms, walnut-sized hail in Des Moines, and 15–20 ft snow drifts in northwest Iowa.

02:11–04:48 — Madelynn leads an ENSO-themed Jeopardy game

04:55–06:35 — Weekly forecast: two low-pressure systems bring widespread rain and strong winds Friday, with possible frost across northern and parts of southern Iowa this weekend; quieter, warmer weather follows next week.

06:40–08:16 — Climate outlook: warm and wet conditions are favored in the 6–10 and 8–14 day periods, with a slight dry lean in weeks 3–4; El Niño tends toward wetter October–November before a drier winter pattern.

08:32–11:46 — Justin reviews strong El Niño analogs, showing warmer historical signals, mixed precipitation patterns, and generally below-normal January–March snowfall—especially in eastern Iowa.

11:50–13:22 — Hazard outlook: an early frost risk verified after several days' notice; CPC flags slight risks for heavy rain October 22–24 and high winds October 22–23.

14:04–16:41 — Frost climatology and context: normal first 32°F freeze ranges from early October in northern Iowa to mid-to-late October in the southeast; recent exceptional warmth makes the upcoming frost feel abrupt but remains seasonally normal.

16:56–20:20 — Past-week review: warm conditions, hail up to 1.75 inches from Sac through Dallas and Warren counties, a surprise Tuesday-morning thunderstorm, and a northwest-to-southeast rainfall band; Sioux City recorded both the weekly high (93°F) and low (39°F).

20:42–21:47 — Discussion of forecast uncertainty: rainfall timing and amounts become more reliable closer to the event, with synoptic-scale patterns often more predictable than localized precipitation bands.

22:05–26:56 — Specialty-crop frost preparations: drain irrigation lines and open valves, protect tender crops, use row cover carefully with hoops to prevent leaf scorch, and ventilate high tunnels to slow overly large overwintered crops and help them acclimate.

26:56–28:16 — Field opportunities: plant garlic and consider overwintered onions, which Dan reports may store better and experience less storage rot than summer-grown onions.

28:16–30:15 — Pest note: leaf-footed bugs are appearing on tomatoes and pumpkins; nymphs are more vulnerable to control than adults, but management remains difficult.

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01:03 — Weather history: An early October 1970 snowstorm brought record-setting snowfall to western and northwestern Iowa, including nine inches in Hawarden.

01:48 — Seven-day forecast: Warm, mostly quiet weather gives way to midweek rain chances, with 1.5–2 inches possible across southern Iowa. Justin explains the Pacific moisture connection.

04:20 — Improving field conditions: Sunshine, low humidity, and breezes help dry topsoil, renewing opportunities for tillage, garlic planting, and root-crop harvest.

05:12 — October outlooks: A near-term wet signal may largely reflect the approaching storm, while longer-range outlooks favor a return to warmer, drier conditions.

07:52 — Weekly weather recap: Heavy rainfall brought 4–6 inches along a band from Pottawattamie County to Waterloo before nearly a week of sunshine. Highlights include an 88°F high, a 34°F low, and 6.49 inches of rain at Portsmouth.

10:06 — Spinach pest spotlight: Identifying suspected beet webworm damage, recognizing its webbing, and discussing Bt treatment and harvest-quality challenges.

11:52 — Regional growing conditions: Dan reflects on central Iowa's unusually cloudy, wet September and acknowledges that eastern Iowa growers have had a different experience.

13:43 — Upcoming grower events: A November 11 high tunnel short course at the Iowa Arboretum and a free November 10 workshop on food safety and organic certification in Stevens Point, Wisconsin.

Summary generated using perplexity.ai

[00:00:31] Iowa weather history: a look back at late-September 1985, when widespread rain, sleet, and snow occurred across Iowa, including trace snowfall in Des Moines.

[00:01:26] Forecast headline: widespread rainfall continues through Thursday night, fueled by tropical moisture associated with Hurricane Polo's remnants, monsoonal moisture, and a larger-scale low-pressure system.

[00:02:00] Pattern change ahead: sunshine, daytime temperatures in the 60s, overnight lows in the 40s, and a drier, less active weather pattern beginning Friday.

[00:02:24] September rainfall records: Des Moines may approach or break its wettest September on record, while only 2.76 inches are needed to break the city's all-time wettest-month record.

[00:03:47] Statewide September climate update: Iowa ranks as the fifth warmest and seventh wettest September in 154 years of records, with some locations receiving May-and-June-scale precipitation totals in one month.

[00:04:51] Extended outlook: the 8-to-14-day and 3-to-4-week forecasts favor a generally drier pattern. Keep an eye on a short-lived period of much-below-normal temperatures 10/6-10/7 in SE Iowa.

[00:07:41] Past-week weather recap: temperatures were slightly below normal for the first time this September, while statewide rainfall averaged 1.26 inches.

[00:08:36] Weekly extremes: Clarinda and Shenandoah reached 80°F; Hampton dropped to 45°F; Missouri Valley received 2.73 inches of rain; and parts along the Iowa-Wisconsin border received little or no rain.

[00:09:20] Specialty-crop update: sweet potatoes are thriving in the warm, wet season, but harvest appropriately sized roots before they become oversized and harder to market.

[00:10:38] Cloud cover and crop growth: Dan and Justin discuss whether unusually cloudy conditions may be limiting photosynthesis, crop sizing, and fall growth; they plan to revisit cloud-cover data next week.

[00:11:42] Fall foliage and warm nights: persistent greenness and delayed leaf-color change may reflect warm overnight temperatures and the broader warming signal associated with climate change.

[00:12:25] Recommended listening: Dan highlights a recent weather-focused episode of the Growing for Market podcast featuring a Northeast meteorologist.

[00:12:57] Grower challenges: growers describe an exceptionally difficult season marked by excessive rain, reduced harvests, poor farmers-market turnout during rain, crop disease and production challenges, and uneven conditions across Iowa.

[00:13:44] Western Iowa perspective: a grower in Manning reports a much drier growing season before September; Justin reviews precipitation observations showing 6.65 inches in Manning during September and about 27 inches for the year in nearby Irwin.

[00:15:37] Pivot Points podcast spotlight: Dan shares his other podcast, which features farmers navigating setbacks and major changes. He highlights a new episode with Cassie and Michael of Crossroads Community Farm near Madison, Wisconsin.

summary generated using perplexity.ai

[00:00:34] Iowa weather history: Justin looks back at September 24, 1985, when snowflakes mixed with rain in Des Moines—among the earliest observations of snow in Iowa history.

[00:01:19] Weather trivia: Which Iowa sector is most vulnerable to climate variability impacts?

[00:01:44] Forecast headline: "endless wet": The team discusses a soggy seven-day outlook, including at least 1.5 inches of statewide precipitation and possible 2–4 inch totals south of a Des Moines-to-Sioux City line.

[00:02:50] Near-term forecast details: Showers continue through Sunday morning, followed by a brief early-week break before rain returns Tuesday. Temperatures remain in the 60s, with mild overnight lows.

[00:03:18] Hurricane Polo and the quiet Atlantic: Justin explains how Pacific Hurricane Polo's remnants may influence Upper Midwest weather, while the group discusses El Niño, wind shear, and the lack of an Atlantic hurricane so far this season.

[00:05:12] 8-to-14-day outlook: Madelynn reviews the early October outlook, which favors above-normal precipitation while keeping temperatures near normal around Iowa.

[00:07:16] Hazards outlook: No notable hazards are highlighted in the 8-to-14-day hazards outlook.

[00:07:32] Past-week weather recap: The group gives the week its "Flood and Furious" headline and talks about widespread wet conditions, and rain impacts across Iowa.

[00:08:46] Iowa weather extremes: Justin reports the wettest location, North Liberty, with 6.75 inches of rain; the driest location, Randolph, with 0.15 inches; and temperature extremes ranging from 97°F in Clarinda to 42°F at Mason City Municipal Airport.

[00:09:49] Summer Glory Index: Justin introduces the Summer Glory Index, a measure combining temperature, humidity, and precipitation to assess how pleasant meteorological summer was.

[00:11:27] Des Moines' wretched summer: Des Moines recorded 43 disqualifying summer days out of 91, including a particularly oppressive July 27, leading to a Summer Glory Index score of 853.

[00:12:07] Putting the summer in context: Dan compares Des Moines' score with Twin Cities history and recent Iowa summers, noting that 2026 skipped past "not glorious" into the "wretched" category.

[00:13:31] Monthly Summer Glory breakdown: June scored 583 points, but July had negative 44.5, illustrating the sharp deterioration in summer conditions.

[00:13:57] The "San Diego of Iowa": Justin identifies Northwood, Iowa, as the Iowa station whose summer temperatures most closely matched a San Diego-like climate.

[00:15:55] Specialty crop impacts and high-tunnel work: Dan shares lessons from helping re-cover the Global Greens greenhouse, including methods for safely installing plastic over high tunnels.

[00:17:16] High-tunnel covering techniques: Dan compares traditional plastic-pulling methods with a ridge-spool approach that can reduce billowing and make wet-weather installation more manageable.

[00:19:04] Inflation-fan advice: Tips for two-layer plastic systems, including installing fans promptly, keeping a backup fan available, and using outside air to reduce interior condensation.

[00:20:39] High-tunnel storm preparation: Dan emphasizes installing anti-billow ropes and keeping a utility knife in every tunnel to protect the steel structure during extreme snow or wind events.

[00:22:25] Caterpillar tunnel inside a high tunnel: Dan discusses Andrew Phelps' planned experiment using a caterpillar tunnel within a high tunnel for added winter insulation.

[00:22:58] High Tunnel Short Course: Registration is open for the November 11 short course at the Iowa Arboretum.

[00:23:13] Hort Friday Field Day delayed: The Iowa Public Radio Hort Friday Field Day is postponed because saturated fields and rain make parking and field access impractical; a new date is expected no earlier than mid-October.

[00:23:38] Trivia answer:

[00:24:24] A difficult growing season: The group reflects on a challenging year for growers, marked by a poor Summer Glory Index and persistently wet September weather.

[00:25:06] Cloud cover and seasonal affective disorder: Madelynn discusses unusually cloudy conditions in Des Moines, with overcast observations occurring 42% of the time this September versus a climatological average of 26%.

Podcast summary generated using perplexity.ai

00:00:42 — Iowa weather history for September 17: a dramatic 1912 transition from record late-season heat to early snow and flurries.

00:01:17 — Weather trivia: How does Des Moines precipitation from September 1–14 rank historically?

00:02:22 — Near-term Iowa forecast: continued chances for rain and thunderstorms through Monday, with the heaviest potential rainfall in northeastern Iowa and a marginal severe-weather risk from southwest into central Iowa Friday night into Saturday.

00:03:44 — CPC 8- to 14-day outlook: warmer-than-normal temperatures favored statewide, with mixed precipitation signals across Iowa.

00:05:01 — October outlook: slightly increased odds of above-normal temperatures in Iowa, while precipitation has equal chances of being above, near, or below normal.

00:06:17 — Why the October precipitation outlook shows a wetter signal to Iowa's southwest, and why drought-stricken neighboring states could welcome that moisture.

00:07:30 — Three-month outlook for October through December: warmer conditions favored, with equal precipitation chances in eastern Iowa and a slightly wetter signal in western Iowa.

00:07:58 — El Niño update and Iowa winter implications: how current Pacific sea-surface temperature anomalies compare with historic strong El Niño events.

00:10:18 — Choosing El Niño analog years: why more recent strong events may be more relevant than older events when accounting for a warmer modern climate.

00:12:38 — Classic El Niño precipitation pattern, jet-stream placement, and the potential for wet conditions extending from the Gulf states into the Midwest.

00:13:17 — Winter weather under strong El Niño: a generally warmer signal, but potential for late-January and February cold-air outbreaks, episodic snowstorms, rain, and mixed-precipitation events.

00:15:32 — Other climate drivers beyond El Niño, including the Madden-Julian Oscillation and Pacific Decadal Oscillation, and uncertainty about ocean-atmosphere coupling and a possible later La Niña transition.

00:16:31 — What "episodic snowfall" means in practice: sharp swings between periods of frigid weather, snow potential, and much warmer conditions.

00:17:53 — How Iowa's currently wet soils affect local weather versus how large winter synoptic-scale systems obtain and transport moisture.

00:19:58 — Past week's headline: exceptionally wet conditions across southwest and central Iowa, despite temperatures generally remaining near normal.

00:21:11 — Dense fog, recent high-wind reports, and how recent temperatures compared with normal across the state.

00:21:53 — Weekly Iowa weather extremes: warmest and coldest observations, plus wettest and driest locations and discussion of CoCoRaHS rainfall reports.

00:25:12 — Specialty-crop impacts of prolonged wet weather: bacterial soft rot in carrots and other root vegetables, raised beds, harvest sanitation, and protecting storage crops.

00:28:31 — Forked carrots: possible causes, marketability, and the history and potential use of baby-carrot processing.

00:29:30 — Black rot in brassica crops: identifying affected cabbage, avoiding storage losses, preventing harvest-tool spread, and sanitizing knives.

00:31:07 — Managing muddy harvested crops, sanitizing wash water, and deciding whether to wash crops before storage.

00:31:50 — Fieldwork and fall planting: garlic planting windows, turfgrass reseeding on damaged field edges, and fall weather considerations.

00:32:46 — Upcoming events: registration for the November 11 high tunnel short course and the September 26 Horticulture Research Station event in Ames.

00:33:55 — Trivia answer

00:34:51 — Historical context for Des Moines precipitation records, including June 1881 as the city's wettest calendar month.

00:35:12 — Closing reflection on historical weather extremes, forecasting, weather-related stress, and the value of discussing mental health.

podcast summary generated using perplexity.ai

[00:00:27] This Day in Iowa Weather History: Early frost event of September 10, 1976; record lows across multiple stations.

[00:01:27] Short-term outlook: No frost risk for Iowa in the next week; 8–14 day hazards show cold risk only in northern Minnesota/Dakotas.

[00:01:47] 7-day forecast headline: Shift to widespread low-pressure systems and fronts; 0.75–2 inches of rain possible; temps cooling toward or slightly below normal.

[00:02:39] Extended outlook: 6–10 day (Sept 15–19) leans warm/wet; 8–14 day (Sept 17–23) near-normal temps with a slight wet signal; slight heavy-precip risk Sept 17–19.

[00:03:31] 3–4 week guidance: Leans warm; no clear precipitation signal.

[00:03:56] Past week recap: Very localized heavy rain in central Iowa (up to ~5–6 inches in parts of the metro) after a hot start to September.

[00:06:42] Weekly extremes: High 100°F at Shenandoah (Sept 8); low 53°F at Lake Park (Sept 9); highest precip 7.69" at Guthrie Center; SE Iowa saw little to no rain.

[00:08:24] Meteorological summer review: Statewide avg temp 72.7°F (+1.3°F; tied 54th warmest); precip 14.32" (+0.76"; 39th wettest); Des Moines area (Climate Division 5) had 11th wettest summer.

[00:10:46] Growing season impacts: Wet periods drove foliar diseases, root rots, and pest pressure; mixed reports on corn rootworm and Japanese beetles; tough year for tomatoes; pumpkins faring better.

[00:12:24] Coming next week: Summer "Glory Index" breakdown using airport sites (NW, NE, SW, SE, plus Des Moines).

[00:13:20] Specialty crop tips:

[00:13:23] Top Brussels sprouts in mid-September to improve uniform bulking.

[00:13:43] Bacterial leaf spot on parsley/celery/cilantro: seed-borne and soil-borne; emphasize seed treatment, hot-water treatment for organic seed, and rotation.

[00:15:54] Copper fungicides: effectiveness varies by product and disease; metallic copper equivalent matters more than % active ingredient; note PHI/REI differences and organic soil-copper limits.

[00:18:31] Winter squash harvest: green radial lines at the stem on butternut can be normal; harvest when rind is tan/buff; cucurbit foliage declining

summary generated using perplexity.ai

I caught up with Dr. Ajay Nair at the 2026 Farm Progress Show in Boone, IA. He shared with me his vision for Horticulture at Iowa State University and in the state of Iowa.

00:00:08 — Welcome to What in the Weather?, recorded from the Farm Progress Show.

00:00:33 — Iowa weather history: the damaging, unusually early statewide frost of September 1, 1859, following late spring frosts and affecting crops including corn, buckwheat, and sorghum.

00:02:04 — Week-ahead forecast: hot, humid conditions, with "ridge rider" thunderstorms bringing a localized risk of heavier rain, especially across northern and northwest Iowa.

00:03:10 — Heat Dome "Fiero" ;-) discussion: a persistent ridge favors heat and relative dryness farther south, while storm tracks ride around its northern edge.

00:04:16 — Extended outlook for September 7–13: above-normal temperatures favored across Iowa, with near-normal precipitation expectations.

00:04:47 — Seasonal market note: continued summerlike heat may support watermelon demand longer than typical fall-oriented sales.

00:06:09 — Preview of next week's meteorological summer recap and the Summer Glory Index outcome.

00:06:33 — Last week's Iowa weather: scattered rain and storms in northern Iowa, dry conditions in several southern areas, a high of 96°F at Lamoni, a low of 48°F at Lake Park and Spencer Municipal Airport, and Rock Rapids' 1.3-inch precipitation total.

00:07:35 — Vegetable crop update: timing for oats-and-peas cover crops, plus considerations for daikon radish and brassica disease management.

00:09:08 — Disease observations in watermelon and brassicas: possible gummy stem blight in watermelon and reports of Xanthomonas leaf spot and black rot in kale, Brussels sprouts, and cabbage.

00:10:48 — Randall Vos joins from the Farm Progress Show to discuss fruit-crop conditions across Iowa.

00:10:56 — Strawberry and tree-fruit season review: weather extremes, frost, rain, disease, uneven fruit set, and thrips pressure contributed to a challenging year.

00:12:10 — Fall raspberries: generally benefiting from adequate moisture, though current heat may cause stress and drooping.

00:12:36 — Moisture-gradient impacts on fruit crops: lower disease pressure in northwest Iowa vineyards versus substantial foliar downy mildew concerns elsewhere.

00:14:07 — Early grape harvest and heavy bird pressure in vineyards, including challenges from robins, starlings, orioles, and turkeys.

00:14:52 — Possible bird damage in tomatoes and how rain can accelerate rot after fruit is pecked.

00:15:38 — High Tunnel Short Course announcement: November 11 at the Iowa Arboretum, with speakers Christa Alexander, Judson Reed, and T.D. Holub covering high-tunnel systems, fertility, cover crops, construction, and crop production.

00:16:42 — Closing and invitation to tune in next week for the meteorological summer recap.

summary generated using Perplexity.ai

Find full show notes at https://www.extension.iastate.edu/commercialhort/82726-notes-what-weather

00:00:32 Iowa weather history: Heavy thunderstorms in 1903 produced extraordinary rainfall totals across southern Iowa, including an unofficial 14.61 inches at Woodburn.

00:01:26 Weather trivia: What causes the reddish, coppery appearance of the Moon during a lunar eclipse?

00:02:00 Weekly forecast: A quieter storm track overall, better rain chances Saturday, slight chances early next week, and temperatures about 5 degrees above normal.

00:02:33 Climate outlook: A warmer-than-normal start to September is favored, while precipitation is expected to be near normal statewide. Southern Iowa faces a slight risk of extreme heat during the September 3–9 period.

00:04:28 Seasonal outlook and El Niño discussion: The hosts examine the September–November outlook, the developing Pacific signal, and how climate models use analogs and trends.

00:06:08 Past-week weather recap: Pleasant temperatures, cool nights, limited rainfall in parts of Iowa, and a reminder to credit the Iowa Environmental Mesonet and Daryl Herzmann when using IEM data. https://mesonet.agron.iastate.edu/onsite/features/cat.php?day=2026-08-27

00:07:52 Iowa temperature and precipitation extremes: Rock Rapids reached 90°F, while Spencer Municipal Airport and Lake Park fell to 47°F; Boone recorded the week's highest precipitation total.

00:08:59 Lunar eclipse viewing: Details on the August 27 deep partial lunar eclipse, including peak viewing at 11:12 p.m. Central Time and 96.3% coverage at maximum eclipse.

00:10:19 Specialty crop impacts: Powdery mildew management, late-season pumpkin guidance, and a diagnosis of Xanthomonas leaf spot in Lacinato kale.

00:12:52 Managing Xanthomonas leaf spot: Resistant cultivars, copper-based treatments, removal of affected leaves, sanitation, crop rotation, and hot-water seed treatment for brassicas.

00:14:33 Wet-season crop challenges: Dan discusses troubleshooting difficult field conditions for a northeast Iowa grower and compares the challenging 2026 season with 2025.

00:15:04 Farm Progress Show preview: The team will record next week's episode from Boone, with Dan staffing the horticulture booth and Madelynn staffing the weather booth featuring IEM and CoCoRaHS.

00:15:48 Trivia answer

00:16:39 Rayleigh scattering explained: Why the sky is blue, and how atmospheric gases scatter light.

00:17:15 Atmospheric moisture and fluid dynamics: A discussion of water vapor's small but important role in weather and the atmosphere as a fluid.

00:18:27 Tornado safety follow-up: Why seeking shelter under an overpass is unsafe, including wind acceleration, debris hazards, and traffic congestion risks.

00:21:09 Closing remarks and a reminder to join the hosts next week for an episode recorded at the Farm Progress Show.

summary generated using perplexity.ai

[00:00:51] Iowa weather history for August 19: A destructive 1898 severe-weather event brought straight-line winds, hail, heavy rain, property damage, and fatalities across northwestern Iowa.

[00:02:00] Why thunderstorms can occur overnight and in the early morning: Justin explains the role of the nocturnal low-level jet, moisture transport, ridge riders, and heat-dome patterns.

[00:03:55] Weather trivia: Is it safe to park beneath an overpass during a storm?

[00:04:37] Short-term forecast: Storm chances return through Friday, followed by quieter, seasonable weather over the weekend and into early next week.

[00:05:26] Extended outlook: Iowa has increased odds of above-normal temperatures in the 8-to-14-day period, while precipitation odds remain near normal.

[00:06:45] Heat dome discussion: The group explains persistent blocking highs, why the current heat dome is lingering, and jokingly suggests naming it "Fiero."

[00:07:36] Three-to-four-week outlook: Equal chances for temperature and precipitation across most of Iowa, with limited areas leaning warmer or drier.

[00:08:35] Hazards outlook: No hazards are forecast for Iowa, though parts of Nebraska, Kansas, and Missouri face a slight risk of hazardous heat.

[00:10:05] Past-week weather recap: Storms became more localized late in the week, after Iowa experienced its wettest week of the year to date.

[00:10:30] Iowa rainfall and temperature extremes: Discussion of statewide precipitation averages, Wapello's 8.76 inches of rain, Rock Rapids' 0.13 inches, and temperatures from 51 to 94 degrees.

[00:14:05] El Niño update: Climate Prediction Center probabilities continue to indicate a strong El Niño event, with potential implications for late fall and winter.

[00:15:10] Specialty crop impacts from recent rain: Tomato cracking, melon splitting, harvest timing, rot, and insect issues following heavy rainfall.

[00:16:47] Powdery mildew in squash and zucchini: Scouting, curative treatment options, resistant varieties, pumpkin-handle impacts, and managing disease before harvest.

[00:19:41] Squash bug management: Identifying vulnerable nymphs, spray options, timing around eggs and hatch, canopy coverage, and cautions when mixing pesticide products.

[00:22:21] Cucurbit yellow vine decline: Yellowing symptoms, adult squash bugs as disease vectors, and end-of-season squash bug management.

[00:23:09] Greenhouse Short Course: Information on the September 16 event at Reiman Gardens for ornamental greenhouse growers.

[00:23:43] Project Monarch Science app: How Bluetooth-enabled monarch tags and citizen-science observations help researchers track migration success.

podcast summary generated using perplexity.ai

00:00:25 — Iowa weather history: two violent 1974 tornadoes caused F4 damage in eastern Iowa.

00:01:31 — Weather trivia asks listeners to identify the leading cause of weather-related fatalities in the United States.

00:01:51 — Near-term forecast: an active "ring of fire" pattern brings widespread thunderstorm chances for the next four to five days, followed by a quieter, seasonable start to next week.

00:02:29 — Rainfall outlook and forecasting explained: model ensembles suggest broad totals of at least 1.5 inches, with isolated 3–4 inch amounts possible from central to eastern Iowa; local thunderstorm totals will remain highly variable.

00:05:18 — Extended outlook: Aug. 19–25 is favored to be warmer than normal in Iowa, with near-normal precipitation; the late-August/early-September outlook leans slightly drier.

00:06:44 — The team explains how Pacific monsoon moisture, the jet stream, and emerging El Niño conditions may contribute to Iowa's humidity and heavy-rain potential.

00:09:08 — El Niño update: European model projections show a potential very strong event later this year, though the hosts emphasize uncertainty and promise a fuller winter-focused discussion.

00:13:37 — Derecho and severe-weather recap: a damaging line of storms crossed eastern Iowa and continued through the Ohio Valley, with wind gusts up to 75 mph near Independence and two reported tornadoes in Delaware County.

00:15:19 — Past-week Iowa conditions: eastern Iowa saw tornado, hail, wind, crop, tree, and building damage; Nashua recorded 3.04 inches of rain, while Rock Rapids had only a trace.

00:16:52 — Recent temperature and humidity context: highs reached 94°F, Spencer fell to 47°F overnight, and the hosts compare this summer's heat and dew points with 2025.

00:18:46 — Specialty-crop update: growers seeking heat-tolerant broccoli varieties are directed to Cornell's Eastern Broccoli Project research.

00:20:14 — Corn rootworm beetles are replacing Japanese beetles as a concern for flowers, pumpkins, and sweet corn; exclusion netting or bags are the most pollinator-safe control options for cut-flower growers.

00:22:51 — Watermelon harvest challenges after heavy rain: excessive moisture can cause splitting, while growers must balance harvest timing, maturity, rind development, and variety-specific traits.

00:25:18 — Hail damage report from Algona: penny-size, likely wind-driven hail damaged zucchini and pumpkins; photos will be included in the show notes.

00:26:32 — Upcoming events: Midwest Mechanical Weed Control Field Day in Michigan (Sept. 16), Appropriate Technology Field Day in Kentucky (Aug. 25), Great Lakes Tek Flex in Michigan (Sept. 10–11), and the 40th-anniversary Hort Friday field day in Ames (Sept. 26).

00:29:25 — Additional event reminders: High Tunnel Short Course on Nov. 11 and the Southeast Research Farm Field Day in Crawfordsville on Sept. 10.

00:29:44 — Trivia answer

podcast summary generated using Perplexity.ai

[00:00:08] August 5 Iowa weather history segment, including a severe 1989 thunderstorm complex and derecho discussion.

[00:01:35] Madelynn shares the weather trivia question: Does Iowa get more than 40% of its annual precipitation in its 10 wettest days?

[00:02:03] Justin gives the upcoming forecast headline: rain chances easing, then a return to mid- to upper-80s temperatures.

[00:05:03] Madelynn reviews the 8-to-14-day and one-month Climate Prediction Center outlooks, which lean warmer and wetter for parts of Iowa.

[00:06:14] The team discusses heavy precipitation risk in eastern Iowa, wet soils, flash flooding concerns, and ridge-rider storm potential.

[00:07:56] Madelynn summarizes the past week's weather shift from hot and humid to cooler, pleasant conditions with soft rains across much of the state.

[00:10:23] Justin shares recent weather extremes, including the hottest location, coolest overnight lows, and top precipitation totals.

[00:11:21] The hosts talk about heavy rain and training lines in southern and central Iowa, plus flash flood concerns and rainfall extremes.

[00:12:51] Dan moves into specialty crop impacts, covering watermelon harvest progress and melon ripening in Iowa.

[00:13:57] Dan discusses broad mites in peppers, including symptoms, scouting, and management challenges.

[00:15:16] The conversation shifts to thrips damage in gladiolus, possible species involved, and treatment considerations.

[00:18:29] Dan explains the difference between truss tomatoes and standard tomato varieties, using a grower example and seed sources.

[00:20:30] Dan notes the first Wisconsin report of beet rhizomania and explains why it matters for beet production.

[00:21:15] The episode includes a listener question about Japanese beetles, their life cycle, and when they should disappear.

[00:23:20] Madelynn answers the trivia question

00:00:08–00:02:00: Dan and Justin discuss the first recorded tornado damage in Iowa history from 1804.

00:02:00–00:04:05: The team previews the coming week's forecast, including heat, muggy conditions, wildfire smoke, and a rain system that could bring widespread rainfall.

00:02:41–00:03:55: Madelynn introduces the weekly trivia question about which RAGBRAI year had the most hours with a heat index above 85 degrees, with a note that Des Moines data is being used as a proxy.

00:04:05–00:08:24: Madelynn walks through the 8–14 day Climate Prediction Center outlook, the hazard outlook, and the three-to-four-week outlook, highlighting above-normal temperatures, near-normal precipitation, and some drought concern.

00:07:39–00:08:24: Dan adds harvest timing advice for potatoes, onions, and garlic ahead of potential rain, and mentions the upcoming final August monthly outlook.

00:08:25–00:10:12: Madelynn summarizes the past week as "moist and on fire," describing heat, humidity, dense fog, and a fire at the Agristar meat processing plant in Postville.

00:10:12–00:11:20: The hosts review extreme heat statistics for Des Moines, including a 1936 record and the near-record heat index from July 27, 2026.

00:11:21–00:13:13: Justin shares weekly weather superlatives, including the statewide high, low, and wettest location, and the hosts correct a questionable Spencer low-temperature reading.

00:13:14–00:16:06: Dan discusses tomato botrytis issues in a high tunnel, possible management options, and whether removing infected plants could spread spores.

00:16:06–00:18:10: Dan shares that he tested positive for Cyclospora, explains the infection route, and talks about antibiotics and sun sensitivity.

00:18:10–00:20:38: The conversation turns to garlic viruses, clean seed production, and how virus-free seed can improve yields.

00:20:46–00:22:24: Dan discusses farm decision-making and labor tracking using the "Know Your Cost to Grow" approach to evaluate equipment investments.

00:22:45–00:23:31: Dan plugs Farm to Table for All, a local produce-purchasing and food-distribution effort in the Des Moines area, and mentions an upcoming event.

00:23:35–00:24:14: Madelynn reveals the trivia answer

00:24:25–00:25:18: Dan closes with thoughts on tailwinds and headwinds during RAGBRAI, congratulates riders, and signs off for the week.

summary generated using Perplexity.ai

00:00:31 Iowa weather history: July 23, 2010 flooding and Delhi dam failure

00:02:03 Trivia question on severe weather warnings in Iowa

00:02:39 Weekly forecast: hot, humid conditions with highs in the mid to upper 90s

00:03:02 Rain outlook: scattered storms, potential for localized heavy rain, low severe risk

00:04:31 Climate Prediction Center outlook: above-normal temps, below-normal precipitation trends

00:05:55 Extended outlooks: limited signals; slight precipitation increase for August

00:06:48 Recent weather recap: storms, uneven rainfall

00:07:58 Wildfire smoke impacts across the Midwest and Iowa

00:10:33 Discussion on repeated heavy rainfall in central Iowa and storm patterns

00:13:44 Temperature extremes: recent highs above 100°F and questionable low temperature readings

00:16:30 Precipitation totals: Osage leading rainfall; continued dryness in northwest Iowa

00:18:51 Home weather station experiment: large discrepancies in rainfall measurements

00:21:50 Specialty crop segment begins

00:22:06 Horticulture Field Day announcement (July 29 in Ames)

00:22:54 Purslane weed management: growth habits and control strategies

00:25:09 Bacterial canker in tomatoes: symptoms and prevention

00:26:17 Rapid crop development due to heat and degree day accumulation

00:26:40 Cyclospora outbreak: food safety considerations and transmission

00:30:12 Trivia answer revealed

Summary generated by Perplexity.ai

It's Swass season, y'all.

00:00:49 – This Day in Iowa Weather History: the 1984 temperature swing from 35°F frost at Elkader to 100°F at Shenandoah in 24 hours

01:19 – Weekly trivia question introduced: what's Iowa's record 24-hour precipitation total?

03:15 – Weather forecast headline: slight severe storm risk overnight, hot and mostly dry week ahead with highs in the low-to-mid 90s

04:12 – Extended climate outlook: hot and dry pattern dominates 6-10 day, and 8-14 day outlooks, with a Level 3 heat risk for northwest/western Iowa July 10-14

08:41 – Past week's weather recap: multiple tornado reports, wind/hail damage, and significant flash flooding over the July 4th weekend

11:09 – Breakdown of extreme rainfall totals from the holiday weekend, including a 12+ inch radar-estimated total near Elkhart and a 10.99" official CoCoRaHS reading in Polk City

11:16 – Guidance on food safety for flooded fields, including National Organic Program waiting periods (90/120 days) and FSMA considerations

15:16 – Why CoCoRaHS gauge density matters, plus a call for listeners to join the network

18:49 – Discussion of why the storm's rainfall was under-forecasted, tied to an upper-level disturbance disrupting the priorheat dome

22:04 – Revisiting "100-year" and "1,000-year" flood terminology and annual exceedance probability

24:23 – Specialty crop impacts: Phytophthora risk in wet cucurbit/pepper fields, growth-regulator herbicide drift symptoms in tomatoes/peppers, and distinguishing drift damage from broad mite infestation

27:03 – Tip on sanitizing surfaces efficiently using a hose-end sprayer

episode summary generated using claude.ai

Resources:

• VDIFN Tool
• Ari's tutorial on YouTube for visual aids
• VDIFN User's Manual
• Crop Risk Tool

[00:00:08] Dan introduces the episode, recorded in advance while he's away, featuring guest Ari Abbrescia, Organic and Sustainable Agricultural Outreach Specialist with UW-Madison Extension.

[00:00:48] Ari provides an overview of the VDIFN (Vegetable Disease and Insect Forecasting Network), including its creators — Dr. Amanda Gevens, Dr. Russ Groves, and Ben Bradford — and its role in supporting integrated pest management across the upper Midwest.

[00:02:06] Dan and Ari dig into a real-world example: why VDIFN appears to show flea beetles absent in Iowa when growers in southern Minnesota are already seeing them.

[00:03:36] Explaining the difference between Fahrenheit degree days (FDD) and growing degree days (GDD), and what those values mean within the flea beetle model.

[00:04:50] Ari clarifies that the VDIFN flea beetle model tracks the first hatched generation — not overwintering adults — which explains the apparent gap between model output and field observations.

[00:07:08] Key takeaway: VDIFN measures risk for damage, not pest presence — an especially important distinction when interpreting disease models like late blight.

[00:07:28] Dan shares how he wants to use VDIFN as a scouting lead-time tool for growers, and discusses Spinosad as a management option against adult flea beetles.

[00:08:42] Ari walks through the seed corn maggot model as a strong example of how VDIFN can directly inform planting timing decisions based on Fahrenheit degree day thresholds.

[00:10:18] Discussion of the early blight model for tomato, including how to use the biofix date and P-day accumulation to time preventative fungicide applications.

[00:11:14] Ari explains what P-days (physiological days) are and how they relate to degree days and disease severity tracking.

[00:14:31] Introduction of the Crop Risk Tool — a newer, still-developing tool built by Ben Bradford that allows users to save named locations, upload CSV field lists, and view risk across multiple models for specific sites.

[00:15:59] A key advantage of the Crop Risk Tool: it includes a 14-day NOAA-based forecast, allowing growers to look ahead and plan management decisions proactively.

[00:17:37] Comparing the two tools — VDIFN excels at visualizing spatial patterns and the movement of pest risk across the landscape; the Crop Risk Tool excels at site-specific, forward-looking risk assessment.

[00:19:23] Dan and Ari share a common wish-list feature: the ability for growers to select and view only their key pests and diseases for a saved location, rather than toggling through categories. Ari adds that text alerts are also a dream feature in early development.

[00:20:10] Dan notes that squash bugs and cucumber beetles are absent from VDIFN, sparking a discussion about overwintering adult pests and the diseases they vector, including bacterial wilt and squash mosaic virus.

[00:21:05] Conversation turns to Western flower thrips and onion thrips — including uncertainty about whether VDIFN's thrips model covers one, the other, or both — and whether the distinction matters for tomato spotted wilt virus management.

Episode summary generated using claude.ai

Welcome & Iowa Weather History: The 1952 F4 Tornado and the Train that raced to outrun it [00:00:07]

7-Day Weather Forecast: Quieter Pattern, QPF Totals, and Warming Trend [00:01:15]

Ring of Fire & Ridge Riders: How the Setup Affects Iowa Rain Chances [00:02:13]

8–14 Day & Monthly Climate Outlooks: Warm Signal, Near-Normal Precip, and El Niño Influence [00:02:39]

8–14 Day Hazards: Slight Risk for High Temps and Heavy Precip in Southern Iowa [00:04:45]

Northwest Iowa Dryness vs. Southeast Wetness: Farmer Reports and Crop Conditions [00:06:56]

Past Week Weather Notables: EF2 Tornado, Tornado Climatology, and Illinois' Record Year [00:07:38]

Temperature Trends: Cooler-than-Normal Stretch Easing Stress from Low Rain [00:11:01]

Weekly Superlatives: Warmest, Coolest, and Wettest/Driest Gauges [00:11:51]

Specialty Crop Impacts: Cabbage Black Rot, Kale Leaf Spots, and Squash Vine Borer Alerts [00:12:48]

Overwintered Onion Success and Weed Management Benefits [00:15:23]

Upcoming Events: Controlled Environment Ag Short Course, ISCGA Field Day, Choose Iowa Farm Crawl [00:16:17]

Special Forecast for Farm Crawl and Next Week's Episode Preview: Pest Forecasting with Degree-Day Models [00:17:57]

Episode summary generated using perplexity.ai

Episode Summary

00:00:32 – Iowa weather history: a severe 1978 thunderstorm with softball-sized hail and damaging winds from Sioux City to Webster City

00:01:09 – Follow-up on the latest recorded frost in Iowa history (June 22, 1902, in Columbus Junction) and the cooler global climate trends of that era

00:02:21 – Weekly forecast: continued active weather, more rain Saturday night into Sunday, near-normal temperatures trending slightly cooler next week, and comfortable dew points

00:03:34 – Breakdown of the storm system moving through Iowa, including a 94 mph wind gust in Marshalltown and discussion of squall lines, the low-level jet, and derecho criteria

00:07:37 – Whether last week's 8-to-14-day hazard outlook predicted this week's severe weather event

00:09:14 – New 8-to-14-day outlook (June 24–30): slightly cooler and wetter than normal, no hazards expected

00:10:06 – Three-to-four-week outlook (June 27–July 10): equal chances for above/below/near normal temperature and precipitation

00:10:35 – Discussion of June running about 4°F above the 30-year average so far

00:11:51 – Past week's weather recap: the June 10 derecho, a tornado in Washington County, and severe wind/hail damage on June 11 in southwest Iowa

00:14:37 – Verification of last week's rainfall forecast (heavy in the southeast, minimal in the northwest) and impacts on weed cultivation

00:15:34 – Weekly weather data: highs, lows, and rainfall totals across the state

00:16:14 – Recap of a windier-than-normal meteorological spring (March–May)

00:17:38 – Outlook for a wetter Gulf/southern US and its connection to a possible cooler July-August-September signal for Iowa

00:20:46 – Drought risk specifically for northwest Iowa given drier conditions there

00:21:32 – Specialty crop pest and disease update: cucumber beetles, squash vine borer, aster leafhopper/aster yellows, Japanese beetles, and halo blight on green beans

00:25:40 – Cool temperatures expected to delay heat-loving crops like tomatoes, peppers, and sweet corn

00:26:29 – Weed control strategy: understanding the "critical weed-free period" for different crops

00:27:39 – Reminder to report suspected herbicide spray drift (2,4-D/dicamba) to IDALS

00:28:52 – Upcoming Controlled Environment Ag Short Course in Ames

summary generated using claude.ai

• [00:00:42] This day in Iowa weather history: a late freeze in 1928 brought 32°F lows to Decorah and frost across the state
• [00:01:22] Weekend forecast: a break from the heat is coming, but severe weather is likely — enhanced risk (3 of 5) for much of Iowa, with 3–5 inches of rain possible in the southern third of the state
• [00:03:15] Climate outlook 6–10 days (June 15–19): 60–70% chance of below-normal temperatures for northern Iowa
• [00:04:24] Climate outlook 8–14 days (June 17–23): continued slight chance of below-normal temps; slightly wetter conditions expected; slight risk of heavy precipitation for eastern Iowa, Illinois, and Missouri
• [00:06:22] Past week recap: eastern Iowa saw 3½ inches above-normal rainfall; statewide temperatures ran 4–10 degrees above normal
• [00:07:49] Extreme data points of the week: high of 95°F at Sioux City; 5.9 inches of rain in Russell (Lucas County); dew points hitting 79°F at Osceola
• [00:09:57] Weather explainer: what is the boundary layer, and why doesn't the overnight low always drop to the dew point?
• [00:11:00] Specialty crop update: tomato trellising, weed control, and irrigation underway; poor strawberry yields reported statewide
• [00:12:31] Pest and disease alerts: growth regulator spray drift reports continue (report to IDALS if you see it); bacterial canker detected in a Kalona greenhouse tomato high tunnel; spider mites active in high tunnels
• [00:14:28] Meteorological spring recap: 7th warmest spring on record at 52°F average; near-normal precipitation; 51 tornadoes reported vs. a climatological average of 38

Summary generated by Claude.ai