riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

St. Croix County Disaster Risk

St. Croix County, Wisconsin

FEMA Risk Rating

Relatively Low

National Percentile

64th

of 3,144 counties

State Rank

#33

of 72 (1 = highest risk)

Flood Risk

64th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 64% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 45% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 85% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 7% of US counties

Risk Overview

About Natural Disaster Risk in St. Croix County, Wisconsin

St. Croix County moderately above average

St. Croix County's composite risk score of 64.12 places it above the national average with a "Relatively Low" rating. The county's risk landscape is defined by extreme tornado exposure and moderate flood vulnerability along the St. Croix River system.

Wisconsin's sixth-riskiest county

At 64.12, St. Croix County exceeds Wisconsin's state average of 59.08 and ranks among the state's more hazard-prone counties. Its elevated risk stems primarily from tornado susceptibility, with a score of 84.80—one of the highest in Wisconsin.

Tornado risk towers over Polk, Pierce

St. Croix County faces substantially higher tornado risk (84.80) than neighboring Polk and Pierce counties, though all three share similar flood vulnerabilities tied to river systems. St. Croix's wildfire risk (45.26) also notably exceeds western neighbors, reflecting its transitional geography.

Tornadoes and river flooding threats

Tornado risk reaches an alarming 84.80 in St. Croix County, making severe thunderstorms the dominant hazard concern across the region. Flood risk scores 64.06, reflecting vulnerability along the St. Croix River and its tributaries during spring snowmelt and heavy rain events.

Windstorm and flood insurance critical

Given tornado risk of 84.80, windstorm and hail coverage should be a top priority for all homeowners in St. Croix County. Those in flood-prone zones near the St. Croix River or tributaries must secure flood insurance, as the county's 64.06 flood risk score indicates significant vulnerability.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in St. Croix County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    85th percentile
  2. #2
    FloodPrepare
    64th percentile
  3. #3
    WildfirePrepare
    45th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: St. Croix County

Risk Verdict

At the 64th percentile nationally, St. Croix County experiences a manageable level of natural hazard risk that falls below the U.S. median. St. Croix County's risk profile calls for targeted preparedness, focusing on the hazard categories that dominate the county's score.

Hazard Breakdown

Tornado risk is St. Croix County's dominant natural hazard, ranked at the 85th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 64th percentile nationally. Additional tracked hazards include wildfire (45th percentile), earthquake (7th percentile).

Preparedness Context

St. Croix County's primary hazard, tornado, ranks at the 85th percentile nationally. In St. Croix County, mobile homes and manufactured housing face significantly higher tornado risk than site-built structures; residents in these homes should identify the nearest permanent community shelter in advance. Flood is the second hazard driver for St. Croix County at the 64th percentile nationally, meaning households should maintain awareness of both severe-weather and flood-specific warning systems. The highest-risk window for tornado fatalities is overnight, when St. Croix County residents may be asleep. A NOAA weather radio with overnight alert capability is the single most impactful low-cost preparedness step available to St. Croix County households.

Regional Context

St. Croix County falls 5.0 points above Wisconsin's typical county risk level, which means the hazard environment here is notably more demanding than the state baseline.

Is your household prepared for St. Croix County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in St. Croix County, WI?
St. Croix County has a FEMA National Risk Index rating of Relatively Low, placing it in the 64th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect St. Croix County?
St. Croix County is evaluated for five major natural hazard types: tornado (85th percentile), flooding (64th percentile), wildfire (45th percentile), earthquake (7th percentile). The highest-risk hazard is tornado at the 85th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does St. Croix County risk compare to the Wisconsin average?
St. Croix County's composite risk percentile is 64th, compared to the Wisconsin state average of 59th percentile. The state's overall risk rating is Relatively Low. This means St. Croix County faces higher natural disaster risk than the typical county in Wisconsin.
Is St. Croix County at risk for tornado?
Yes, St. Croix County's tornado risk is at the 85th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, St. Croix County is at the 64th percentile.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Why is St. Croix County higher risk than average?
St. Croix County's composite risk score of 64th percentile is above the Wisconsin state average of 59th percentile. This elevated risk is driven by tornado exposure (85th percentile), along with flooding risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

Data Source

Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.

Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.