Calvert County, Maryland: Natural Disaster Risk and History
Calvert County, Maryland has a Very Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 28.9 out of 100, higher than about 28% of US counties, with hurricanes, landslides and heat waves scoring highest of its 18 hazards and $16 million a year in expected losses.
OpenFEMA lists 22 federal disaster declarations that included Calvert County since 1972, not counting 2 for COVID-19; the latest is EM-3634-MD (Severe Winter Storm, declared 24 January 2026). NOAA's Storm Prediction Center recorded 19 tornadoes touching Calvert County from 1950 to 2025.
Live weather alerts for Maryland All official warnings Latest FEMA declarations
Population 92,747 Buildings worth $18 billion Area 349 sq mi Risk rank in Maryland 22 of 24 FIPS 24009
All 18 hazards, highest risk first
FEMA National Risk Index| Hazard | Risk rating | Score | Expected loss a year | How often | Events in record |
|---|---|---|---|---|---|
| Hurricane | Relatively Moderate | 81.7 | $4.0 million | about once every 9.1 years | 36 |
| Landslide | Relatively Low | 69.2 | $9,277 | about once every 6.9 years | — |
| Heat wave | Relatively Low | 68.5 | $1.5 million | about 6.4 a year | 107 |
| Drought | Relatively Moderate | 67.0 | $725,305 | about 3.6 a year | 91 |
| Lightning | Relatively Moderate | 59.7 | $559,368 | about 39 a year | 52,884 strikes |
| Coastal flooding | Relatively Low | 59.4 | $754,466 | about 3.7 a year | — |
| Winter weather | Relatively Low | 53.2 | $120,618 | about 6.8 a year | 130 |
| Wildfire | Very Low | 52.6 | $91,429 | rarer than once in 1,000 years | — |
| Earthquake | Very Low | 50.1 | $467,253 | about once every 917 years | — |
| Strong wind | Relatively Low | 48.6 | $894,226 | about 5.6 a year | 153 |
| Ice storm | Relatively Low | 39.6 | $87,620 | about once every 2.5 years | 20 |
| Inland flooding | Very Low | 28.9 | $5.7 million | about 1.1 a year | 32 |
| Hail | Very Low | 27.8 | $182,841 | about 2.8 a year | 117 |
| Cold wave | Relatively Low | 26.6 | $603,175 | about 1.1 a year | 20 |
| Tornado | Very Low | 17.3 | $314,831 | about once every 4.7 years | 17 |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Insufficient Data | — | — | — | — |
| Volcanic activity | Not Applicable | — | — | — | — |
Score: FEMA's percentile among US counties that face the hazard (higher = more risk). Expected loss: FEMA's modelled average yearly loss to buildings, people (as a statistical value) and crops. How often: FEMA's annualised frequency of the hazard in the county; for some hazards it counts event-days, so it is a rough guide, not a forecast. "Not Applicable" means FEMA does not model that hazard here.
Federal disaster declarations 22
Most common: Hurricane 8, Snowstorm 6, Severe Storm 4, Flood 2.
| Decade | Declarations | Incident types |
|---|---|---|
| 1970s | 4 | Flood ×2, Severe Storm, Snowstorm |
| 1990s | 4 | Snowstorm ×3, Hurricane |
| 2000s | 5 | Hurricane ×2, Severe Storm ×2, Tornado |
| 2010s | 7 | Hurricane ×4, Snowstorm ×2, Severe Storm |
| 2020s | 2 | Winter Storm, Hurricane |
The last 10
Widest declarations that included Calvert County
- Severe Winter Storm (2026, EM-3634-MD): 24 Maryland counties designated.
- Hurricane Sandy (2012, DR-4091-MD): 24 Maryland counties designated.
- Hurricane Sandy (2012, EM-3349-MD): 24 Maryland counties designated.
Named storms in its declarations: Tropical Storm Isaias (2021), Hurricane Sandy (2012), Hurricane Irene (2011), Hurricane Katrina (2005), Hurricane Isabel (2003), Hurricane Floyd (1999), Tropical Storm Agnes (1972).
Not counted above: 2 COVID-19 ("Biological") declarations — in 2020 every US county was included. Maryland also had 1 statewide declaration with no county list.
Tornado record since 1950 19
| Tornadoes touching the county | 19 |
|---|---|
| Strongest-rated | (E)F4 ×1 |
| Peak month | April (4) |
| Deadliest | 28 Apr 2002, F4, 38 mi path, 3 killed, 122 injured |
| Longest path | 28 Apr 2002, F4, 38 mi path, 3 killed, 122 injured |
| Most recent | 4 Aug 2020, EF0, 0.8 mi path |
| Deaths / injuries on those paths | 3 / 123 |
| Rating | (E)F0 | (E)F1 | (E)F2 | (E)F3 | (E)F4 | (E)F5 | Unrated |
|---|---|---|---|---|---|---|---|
| Count | 9 | 7 | 2 | 0 | 1 | 0 | 0 |
| Decade | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
|---|---|---|---|---|---|---|---|---|
| Count | 0 | 0 | 2 | 2 | 3 | 7 | 3 | 2 |
Deaths and injuries are for each tornado's whole path, which can run beyond this county. F-scale ratings before February 2007, Enhanced Fujita (EF) after.
How Calvert County compares with its 5 nearest counties
| County | Distance | Overall risk | Score | Top hazard |
|---|---|---|---|---|
| Calvert County (this page) | — | Very Low | 28.9 | Hurricane |
| St. Mary's County | 28 km | Very Low | 42.6 | Hurricane |
| Charles County | 37 km | Relatively Low | 44.1 | Heat wave |
| Prince George's County | 39 km | Relatively Moderate | 93.2 | Winter weather |
| Talbot County | 49 km | Very Low | 42.4 | Drought |
| Dorchester County | 50 km | Relatively Low | 53.8 | Coastal flooding |
Nearest by distance between county centres. Every county in Maryland, ranked.
Vulnerability and resilience
| Social vulnerability | Very Low 10.6 |
|---|---|
| Community resilience | Very High 93.8 |
| Community risk factor | 0.62 |
| Expected annual loss, all hazards | $16 million |
FEMA scales expected losses up where social vulnerability is high (people who may find it harder to prepare, evacuate or recover) and down where community resilience is high. A factor above 1 raises the risk score. For social vulnerability a high rating is worse; for resilience a high rating is better.
Prepare for Calvert County's main hazards
- Right now: National Weather Service alerts for Maryland · all official warnings on Global Incident Tracker.
- Hurricane: Is there a hurricane now? · Cyclone preparation
- Landslide: Landslides recorded
- Heat wave: Heatstroke warning signs
- Your property's flood zone: FEMA Flood Map Service Center ↗ — this page cannot tell you that.
- Official preparedness guidance: Ready.gov ↗ and your county emergency management office.
What this page shows, and what it misses
FEMA's National Risk Index rates a whole county against every other US county; it is a planning-level estimate for nationwide comparison, not a flood-zone map and not a substitute for a local risk assessment or the risk to one home. Declarations are presidential disaster, emergency and fire management declarations that named this county; state declarations and SBA or USDA designations are not included. Tornadoes are counted when the county is one of up to four listed on the track; 670 tornadoes that crossed a state line carry no county list in NOAA's file and are left out.
Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties - v1.20.0 (December 2025). Retrieved from https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/National_Risk_Index_Counties/FeatureServer/0/query on November 2, 2026, 1:20 PM EST. This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: Disaster Declarations Summaries - v2, retrieved from https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries on November 2, 2026, 1:21 PM EST. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Tornado records: NOAA/NWS Storm Prediction Center, Severe Weather Database, tornadoes 1950–2025 (https://www.spc.noaa.gov/wcm/data/1950-2025_actual_tornadoes.csv, downloaded 2 November 2026). Public domain; not endorsed by NOAA. Compiled by Global Incident Tracker.
Questions about Calvert County
What natural disasters is Calvert County, Maryland most at risk from?
Calvert County, Maryland has a Very Low natural-hazard risk rating in FEMA's National Risk Index (v1.20, December 2025): a score of 28.9 out of 100, higher than about 28% of US counties, with hurricanes, landslides and heat waves scoring highest of its 18 hazards and $16 million a year in expected losses.
How many federal disaster declarations has Calvert County had?
OpenFEMA lists 22 federal disaster declarations that included Calvert County since 1972, not counting 2 for COVID-19; the latest is EM-3634-MD (Severe Winter Storm, declared 24 January 2026). Another 1 Maryland declarations were made statewide without a county list.
How many tornadoes have hit Calvert County?
NOAA's Storm Prediction Center recorded 19 tornadoes touching Calvert County from 1950 to 2025. The deadliest: 28 Apr 2002, F4, 38 mi path, 3 killed, 122 injured (deaths and injuries are for the whole path).
Is the National Risk Index a flood zone map?
No. The National Risk Index is a planning-level estimate for a whole county, built for nationwide comparison. It does not tell you the flood zone or the risk of a single property: for that, look up the address on FEMA's Flood Map Service Center (msc.fema.gov) and ask your local floodplain manager.