Should I Spray? Live Spray Conditions
Check whether it's safe to spray right now. Allow your location or enter a city or ZIP, and you'll get an instant Good / Marginal / Do Not Spray verdict built from live wind, gusts, rain chance, humidity, and temperature — plus today's hour-by-hour spray windows and your current 2-inch soil temperature. No signup required.
How this spray conditions calculator works
Drift, wash-off, and volatilization are what turn a routine application into a callback, a damaged neighboring plant, or a wasted tank. The biggest controllable factor is the weather window you choose. Sustained wind at or above 15 mph (or gusts at or above 20 mph) is a hard stop for most herbicides because fine droplets carry off-target; very calm air below about 2 mph paired with a temperature inversion is just as risky because the spray cloud hangs and moves sideways instead of settling. The sweet spot for most spraying is a steady 3–10 mph breeze.
Rain timing matters just as much as wind. A high chance of rain within four hours can wash a contact or systemic product off the leaf before it's absorbed, so this tool downgrades the verdict when near-term rain is likely. Heat and low humidity raise volatilization and plant-stress risk — temperatures at or above 90°F, or above 85°F with humidity at or below 30%, push the verdict toward Do Not Spray. The hourly strip below the verdict shows which of the next twelve hours look sprayable so you can plan around the bad windows instead of guessing.
Soil temperature is included because timing for pre-emergents, soil-applied products, and many turf treatments keys off the soil, not the air. The 2-inch soil-temperature reading is the depth most lawn-care thresholds reference — for example, crabgrass pre-emergent goes down before soil holds 55°F. Read the verdict as a decision aid, not a substitute for the product label: always follow the label's wind, temperature, and rainfast guidance, and check your own conditions on site before you spray.
Frequently asked questions
How do I know if it's safe to spray today?
Check live wind, gusts, rain chance, humidity, and temperature for your exact location. As a rule of thumb, spray in a steady 3–10 mph breeze, avoid sustained wind at or above 15 mph or gusts at or above 20 mph, skip it when rain is likely within four hours, and stop when temperatures reach 90°F. This tool combines all of those into a single Good / Marginal / Do Not Spray verdict.
What wind speed is too high for spraying?
Most labels and applicators treat sustained wind at or above 15 mph, or gusts at or above 20 mph, as too windy because fine droplets drift off-target. Wind from about 3 to 10 mph is ideal. Dead-calm air below roughly 2 mph can also be risky when a temperature inversion traps the spray near the ground.
Why does soil temperature matter for spraying?
Many lawn-care products are timed to soil temperature rather than air temperature — pre-emergents, for example, should go down before the 2-inch soil holds 55°F. The tool shows the current 2-inch soil-temperature reading so you can line up soil-driven applications with the right window.
Is this spray-conditions checker free?
Yes. The verdict, current conditions, hourly spray windows, and soil temperature are all free with no signup. You can optionally enter your email to get this week's spray windows sent to you, but it's never required to see the live results.
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