U.S. drought map: the whole country, every week.

A weekly expert assessment, not a sensor feed

The U.S. Drought Monitor is produced jointly by the National Drought Mitigation Center at the University of Nebraska–Lincoln, the U.S. Department of Agriculture, and NOAA. Unlike almost every other layer on this site, it is not an instrument reading: a rotating team of authors synthesises dozens of inputs — precipitation totals, soil moisture, streamflow, reservoir and groundwater levels, snowpack, evaporative demand — together with field reports from observers across the country, and draws the boundaries by judgement.

That is a strength and a limit at once. It means the map reflects conditions on the ground rather than one variable's arithmetic, and it means the map is a considered analysis with a date on it, not a live gauge. It is the reason drought policy, USDA disaster designations, and many state water restrictions key off this map specifically.

Valid Tuesday, published Thursday

Each map is valid for a Tuesday and released the following Thursday morning, incorporating data through that Tuesday morning. So the current map is always a few days behind the weather — a storm that arrives on Wednesday shows up in next week's release, not this one. The week each map covers is stamped beside the map here, and nothing on this page implies live conditions.

The five categories

D0 through D4 run from abnormally dry to exceptional drought. Categories are set against the historical record for that place: roughly, D0 conditions occur about one year in five, D1 one in ten, and D4 less than one year in fifty. That is what makes the scale comparable between Arizona and Vermont — each is measured against its own normal, not against a national rainfall figure.

• D0 Abnormally dry

  Going into or coming out of drought — short-term dryness slowing planting or growth

• D1 Moderate drought

  Some damage to crops and pasture; streams, reservoirs, or wells running low

• D2 Severe drought

  Crop or pasture losses likely; water shortages common and restrictions imposed

• D3 Extreme drought

  Major crop and pasture losses; widespread water shortages or restrictions

• D4 Exceptional drought

  Exceptional and widespread crop and pasture losses; shortages creating water emergencies

The percentages nest — D3 is counted inside D0

This is the single most misread thing about drought data. The Drought Monitor's published percentages are cumulative: when a figure says 29% of the lower 48 is in severe drought, it means D2or worse, and it already includes every acre in extreme and exceptional drought. The consequence is that the five figures do not add up to 100 and were never meant to. Every figure on this page is labelled "or worse" for that reason.

The shaded areas on the map work the other way round: each one is at exactly one category, so the bands sit beside each other rather than inside each other — the extreme-drought ring surrounds the exceptional-drought core rather than containing it. That is why switching a category off on the map removes that band and shows bare ground beneath, instead of demoting it to the next category down. One dataset, two conventions, and knowing which one you are reading is most of the work.

It describes areas, not addresses

The Drought Monitor is drawn at county-to-regional scale. It is authoritative for a watershed, a county, or a state; it is not a statement about a single field, well, or river reach. A specific stream can be running far below its own normal inside an area the map shows as merely abnormally dry, and vice versa — which is exactly why our streamflow map exists alongside this one, and why a monitoring program needs the reach-level reading as well as the regional picture.

Drought is an input, not a conclusion

For the organisations Driftwise works with — watershed councils, fisheries programs, paddle-trail and river-corridor managers, habitat restoration crews — a drought category is the start of a decision, not the end of one. Sustained drought raises stream temperatures and drops dissolved oxygen, narrows the window for spawning surveys and restoration planting, closes access points, and changes the risk calculus for every reach in a corridor.

Driftwise watches drought as one of more than a dozen federal inputs on each monitored reach, alongside USGS gauge readings, NOAA flow and flood forecasts, EPA water-quality designations, wildfire proximity, and air quality — each read against its own healthy range. The map above is the national picture; the product is what happens when that picture is resolved down to the specific stretch of river a crew is responsible for.

Watershed Explorer

Click any point in the country and read what six federal datasets say about it — flow, drought, fire, flood forecast, satellite cyanobacteria screening and Clean Water Act impairment — each one labelled with what it is actually a fact about.

Wildfire & Smoke Map

Official NIFC fire perimeters and incident points under NOAA’s HRRR-Smoke near-surface forecast, filterable by size, state, and containment.

Streamflow Map

Every reporting USGS stream gauge in the country, coloured by how today’s flow ranks against that gauge’s own record for this calendar day.

Flood Outlook Map

NOAA’s river forecast centres call the next few days at every forecast gauge in the country, on the National Weather Service’s own flood categories — action, minor, moderate and major.

Impaired Waters Map

Every subwatershed in the country against the states’ own Clean Water Act assessments — what is impaired, what is still on the 303(d) list, what is causing it, and how much of the country nobody has assessed at all.

Cyanobacteria Bloom Map

NASA and EPA’s satellites read a pigment index over roughly 2,300 U.S. lakes large enough to resolve at 300 m. A pre-screening indicator, not a health assessment, and never a substitute for your state’s advisory.

Critical Habitat & Protected Waters Map

Every river and stream the federal government has designated as ESA critical habitat, the listed species each unit is designated for, and who manages the protected land around it.