Wisconsin Pest Forecast: What to Expect Spring 2026

Spring 2026 is bringing a familiar but increasingly data-predictable pattern to Wisconsin: as temperatures climb above 45°F and spring rains saturate the soil, pest populations are emerging on schedule. Our weather-driven scoring models track these transitions in real time across 59 Wisconsin cities.

What's Active Right Now

As of mid-April 2026, here's the pest landscape across Wisconsin's major metro areas:

• Ticks — Season is fully underway. Scores range from 40-75 across southern Wisconsin cities. Deer tick nymphs are questing in wooded and tall grass areas. Milwaukee tick forecast →
• Ants — Moderate to high activity following spring rains. Carpenter ants and pavement ants are invading homes as colonies are flooded. All Wisconsin ant forecasts →
• Termites — Swarm season has begun. Warm rain events are triggering swarms across southern Wisconsin. Scores climbing in cities with 65°F+ soil temps.
• Mosquitoes — Still early season (low-moderate). Standing water from snowmelt is creating early breeding sites. Expect rapid escalation in May. Madison mosquito forecast →

Weather Conditions to Watch

Three weather patterns will determine how severe pest season becomes this spring:

1. Spring rainfall totals. Above-average April-May rainfall will amplify mosquito breeding and drive more ant invasions. Our models show that each 0.25" of rain in 24 hours increases ant risk scores by 15-20 points.
2. Temperature consistency. Sustained 50-70°F temperatures — without cold snaps — allow tick populations to establish early. One hard freeze after warm-up can temporarily suppress activity but won't end the season.
3. Humidity trends. When humidity stays above 70% for multiple days, tick and termite scores spike. This is the #1 factor our models use for tick risk.

Spring Prevention Checklist

Whether you hire a professional or DIY, these spring tasks dramatically reduce pest pressure:

May-June Outlook

Based on Open-Meteo seasonal data and our historical models, expect:

• • Tick peak: Late May through June — highest tick scores of the year
• • Mosquito surge: First major wave after Memorial Day warm-up
• • Wasp season starts: Queens establish nests in May, colonies grow through June
• • Ant pressure: Continues through summer, worst after heavy rains

Bookmark your local forecast page and we'll keep you updated every 3 hours throughout the season.