Which U.S. counties have the lowest crop insurance coverage in drought?
The U.S. Drought Exposure Monitor is an interactive county map filterable by state and crop that answers this every week. It overlays federal crop-insurance coverage rates from USDA's Risk Management Agency with current drought severity from the U.S. Drought Monitor and NOAA's 90-day outlook — then scores every U.S. county on where the gap between planted acres and insured acres overlaps with active drought. Free, open-source, public-data only.
What this tool answers
The Monitor combines federal crop-insurance coverage rates, current U.S. Drought Monitor severity, NOAA's 90-day Seasonal Drought Outlook, and county-level planted acres into a single county-by-county view. It answers questions like:
- Which U.S. counties have the lowest federal crop insurance coverage right now, and how many of them are currently in drought?
- Where is the coverage gap — uninsured planted acres — concentrated for corn, soybeans, wheat, cotton, and sorghum?
- Which counties' growing seasons are forecast to worsen under NOAA's 90-day Seasonal Drought Outlook?
- How does this week's drought map compare to the same week last year?
How exposure is calculated
Each county gets one composite score, built in three steps:
- Planted acres. USDA NASS publishes planted acres by county and crop. For the current year, the tool walks a three-tier waterfall — county-level actuals when available, otherwise state-level scaled by the county's three-year share, otherwise the most recent prior year — so every county has a defensible acreage number.
- Insured acres. RMA's Summary of Business reports federal crop-insurance policies by county, crop, and coverage type. Dividing insured acres by planted acres yields a coverage rate. One minus the coverage rate is the coverage gap — the share of planted acres with no federal policy attached.
- Drought severity. The U.S. Drought Monitor publishes a five-band severity map every Thursday morning. The tool reads each county's worst current band (D0 through D4) and multiplies it against the coverage gap and planted-acre weight to produce a single county-level exposure score.
The result is a single number per county that captures all three forces at once. The map and watch list rank from highest to lowest exposure, and the scatter view below surfaces the top-right cluster — counties with both thin coverage and deep drought, sized by how many acres are involved.
Drought exposure by crop
The Monitor tracks five federally insured U.S. row crops. Each crop has its own geography, its own typical insurance coverage rate, and its own drought-stress window — so the watch list for one rarely lines up with the watch list for another.
Data sources
Every input is public, freely available, and refreshed on a known cadence:
| Source | What it provides | Refresh |
|---|---|---|
| USDA NASS | Planted acres by county and crop (corn, soy, wheat, cotton, sorghum) | Annual + intra-year revisions |
| USDA RMA Summary of Business | Federally insured acres by county, crop, and coverage type | Monthly mid-year + crop-year close |
| U.S. Drought Monitor | Current drought severity (D0–D4) by county | Weekly, Thursdays |
| NOAA CPC Seasonal Drought Outlook | 90-day forward outlook — development, persistence, improvement, removal | Monthly |
Methodology in plain English
Federal crop insurance is the largest farm-safety-net program in the United States, but participation is uneven. Major Corn Belt counties have near-universal participation in corn and soybean policies; specialty-crop counties, mixed-operation regions, and parts of the country with low historical loss ratios often run much thinner. The Monitor highlights the counties where that thin coverage overlaps with active drought.
The Monitor surfaces those counties by reporting three numbers together — planted acres, coverage gap, and drought severity — instead of one at a time. The full methodology and source are open on GitHub.
Frequently asked questions
What is "coverage gap" on the map?
Coverage gap is the share of a county's planted acres that do not have a federal crop-insurance policy attached. It is calculated as 1 − (RMA insured acres ÷ NASS planted acres) for the most recent crop year. A coverage gap of 60% means roughly six out of every ten planted acres in that county had no federal policy on file.
Why do some U.S. counties have such low federal crop insurance coverage?
Participation varies by crop, region, and producer. Major Corn Belt counties tend to be near-universal on corn and soybean policies. Coverage thins in counties dominated by specialty crops, in regions where premiums are high relative to historical losses, and where private alternatives or self-insurance dominate. The Monitor highlights the counties where that thin coverage meets active drought.
How often is the data refreshed?
Drought severity and the seasonal outlook refresh every Thursday afternoon, a few hours after the U.S. Drought Monitor publishes. RMA Summary of Business updates monthly mid-year and again at the close of the crop year. NASS planted-acre estimates promote from March prospective to June acreage to final, automatically, as USDA publishes.
Is the U.S. Drought Exposure Monitor free?
Yes. The tool is free to use with no signup, and the source code and methodology are open on GitHub.
Which crops are covered?
The major federally insured row crops: corn, soybeans, wheat (excluding durum, which NASS does not publish at the county level under that series), cotton, and sorghum. These crops cover the bulk of insured U.S. acres.
Can I use the underlying data for my own analysis?
Yes. Every input is public USDA, NOAA, or U.S. Drought Monitor data, and the project links to each source. Attribution to the original federal sources is appreciated.