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Johnston, IA Weather
Current conditions
Forecast for this hour (no station report in the last two hours)
Forecast
10-day-
Friday Night
Partly cloudy, with a low around 58.
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Saturday
Partly sunny, with a high near 76.
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Saturday Night
Mostly cloudy, with a low around 56.
National Weather Service forecast updated 3 days ago.
Hourly
Hourly forecast- Now64°
- 10 PM63°
- 11 PM62°
- Sat12 AM62°
- 1 AM61°
- 2 AM60°
- 3 AM60°
- 4 AM59°
- 5 AM59°
- 6 AM58°
- 7 AM59°
- 8 AM60°
- 9 AM62°
- 10 AM64°
- 11 AM67°
- 12 PM70°
- 1 PM73°
- 2 PM75°
- 3 PM75°
- 4 PM75°
- 5 PM74°
- 6 PM71°
- 7 PM69°
- 8 PM67°
10-day forecast
Details- TonightOct 20Partly Cloudy49°
- WedOct 21Mostly Sunny50°75°
- ThuOct 22Sunny54°76°
- TodayOct 23Mostly Sunny58°75°
- SatOct 24Partly Sunny56°76°
- SunOct 25Slight Chance Rain Showers29%49°68°
- MonOct 26Chance Rain Showers29%45°60°
- TueOct 27Mostly Sunny14%59°
- WedOct 28Showers0.35 in50°68°
- ThuOct 29Partly cloudy36°50°
Days after the National Weather Service's seven are MET Norway's outlook, a computer model with no forecaster's review.
Radar
Full mapWeather news near Johnston
More weather news-
Dangerous Freeze Warnings Issued for Iowa, Wisconsin, Minnesota and Illinois as Temperatures DropFreeze Warnings take effect early Saturday across much of Iowa, Wisconsin, southeast and central Minnesota and northern Illinois, with lows as cold as 26 degrees expected. Seven National Weather Service offices issued…
- Freeze Warning Issued For Wapello County
A freeze warning has been issued for Wapello County, including Ottumwa, for early Saturday morning. The National Weather Service says temperatures could drop as low as 31 degrees, with the warning in effect from 1 a.m…
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Widespread Freeze Warnings Issued Across Iowa as Temperatures Could Drop Into the 20s Saturday MorningA widespread round of freezing temperatures is expected across Iowa early Saturday morning, prompting the National Weather Service to issue Freeze Warnings, Freeze Watches, and Frost Advisories for the entire state…
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Looking ahead: Iowa's winter weather outlookOur first frost of the season is already on the way, but what will be in store for the upcoming winter months? This Thursday the National Oceanic and Atmospheric Administration (NOAA) released its winter outlook with…
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Freeze Watch Issued for Much of Iowa as Temperatures Could Drop Into the 20s Saturday MorningMuch of Iowa could experience a widespread freeze this weekend as colder air moves into the region, bringing some of the lowest temperatures of the fall season. The National Weather Service has issued a Freeze Watch for…
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More than a wet month: A review of September’s rainfall effects on Iowa farmersRain, rain and more rain. That’s what this September has looked like for Iowans. This affects everyone, from students walking to class through the rain to the local farmers waiting to harvest their crops. We have seen a…
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Iowa weather: Warm days continue into the weekendWe will continue to enjoy sunny weather for the rest of the week. Today is no exception, with highs in the mid- to upper-70s and south winds around 5 to 10 mph. A light layer may still be warranted for some of us, with…
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Corn and Soybean Harvest Behind Schedule in Iowa, First Frost of Season SeenCorn and soybean harvest is behind schedule in Iowa. Ninety-eight percent of corn has reached maturity, which is even with the five-year average. Twenty-six percent of corn has been harvested, which is 24 percentage…
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Iowa weather: Warm, dry conditions will come to an end next weekClouds will linger a bit this morning, but most of the state will stay dry. Interactive Radar | Weather Alerts | Skycams There have been a few showers early this morning to the south and west, but the moisture is…
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Warm and dry weather pattern holds across IowaKWWL Unseasonably warm and dry conditions will continue tonight across Waterloo and much of Iowa. Patchy morning fog is possible, with a chance of rain returning this weekend.
Air quality
Acceptable. Unusually sensitive people should consider limiting prolonged outdoor exertion.
Forecast
- FriModerate
- SatModerate
- SunModerate
Des Moines, IA reporting area · 1 hr ago. Data from AirNow (EPA and its state, local and tribal partners); preliminary and subject to change.
Sun & moon
Almanac
MonthlyDes Moines Intl Ap, records since 1939. Normals 1991–2020. Data from NOAA's Regional Climate Centers (ACIS).
Nearby
Forecasters' discussion
From the National Weather Service office in DMX, issued 2 hrs ago
Key Messages
- Warm and dry conditions continue Saturday. Elevated fire weather conditions in cropland.
- Rain chances increase slowly from the northwest, cooling temperatures within and to the north of rain.
- Stalled boundary will bring split weather conditions next week: Seasonal temperatures north, warm south. Rain chances remain in the picture.
Short Term
Issued at 238 PM CDT Fri Oct 23 2026
Showers hung on in northern Iowa this afternoon. Ceiling heights in observations were above 15kft and soundings show a dry sub-cloud layer. Dew points at the surface mixed into the upper 40s where clouds didn't reach and winds gusted between 20 and 30mph. Midlevel moisture will continue to be advected northward as the northern segment of the western CONUS trough ejects northward. The southern piece of the trough will remain closed off and stuck in the southwest US. Meanwhile, high pressure is stuck in the Midwest to our east. This is blocking the cold front of the northern stream wave, stalling it in northwest Iowa through the weekend. Rain chances will be in play in the north and northwest, mainly in the overnight hours. Clouds will be common across the area due to moisture advection.
The southern portion of the trough will start to fill and migrate northeast into the Plains, bringing increased rain and clouds to the area to end the weekend and begin the following week.
Long Term
Issued at 238 PM CDT Fri Oct 23 2026
On late Monday, the wave will tilt negatively across southeast South Dakota. Some CAPE is tucked right in the triple point, but the speed of the system keeps the warm sector out of the state until the overnight hours. CAPE will build on the warm sector of the front as it stalls across the middle of the state. Much of next week will have split weather between the north and southern half. The northern half will have more seasonal temperatures whereas 70 degree highs will be common across the south. Rain and some thunderstorms will remain in the picture. This pattern will remain until the east CONUS ridge is broken down by a stronger system from the west.
Aviation
Issued at 629 PM CDT Fri Oct 23 2026
VFR conditions are expected to prevail through the TAF period. Main impact through the overnight will be marginal LLWS particularly at KFOD/KMCW, though shear is not expected to be strong enough to include in this issuance. Though 2kft winds may be >30 knots, surface winds look to stay strong enough to lessen the shear.
Forecasts, observations and alerts in the United States come from the National Weather Service (NOAA); radar from NOAA's Multi-Radar Multi-Sensor system; satellite imagery from NASA's Global Imagery Browse Services (GIBS) and NOAA's GOES satellites; the map from the U.S. Geological Survey's National Map; air quality from AirNow (EPA and its partners); hurricane information from the National Hurricane Center; climate normals and records from NOAA's Regional Climate Centers (ACIS). Forecasts outside the United States and the UV index: MET Norway (CC BY 4.0); observations outside the U.S.: airport reports via NOAA's Aviation Weather Center. Place names: GeoNames (CC BY 4.0). Data are copied on a schedule and may lag the sources; for warnings that affect your safety, follow your local National Weather Service office and emergency officials. Weather news is drawn from the 4Search index and reflects what the press published. Terms of use.