Union County, Pennsylvania
Natural disaster risk, federal disaster history and flood insurance facts.
Union County, Pennsylvania has a relatively low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is higher than 55% of US counties. It ranks 50th of 67 counties in Pennsylvania. The costliest hazards here are inland flooding, strong wind and hurricanes. FEMA estimates about $14 million a year in expected losses, or roughly $338 per resident. Since 1972 it has been included in 16 federal disaster or emergency declarations for natural events (11 major disasters). The most recent was in September 2024 (Tropical Storm Debby). About 1 in 50 homes here carry federal flood insurance (231 policies). Since 1978, federal flood insurance has paid about $12 million on 927 claims here.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Union County
- Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
- Price a flood policy now. Most new federal policies take 30 days to start.
- Secure outdoor furniture and trash bins before storms.
- Have trees near the house checked.
- Know your evacuation zone and route before June 1.
- Ask about roof age, shutters and the separate wind or hurricane deductible on your home policy.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Inland flooding | 71.8 | $11M | ||
| Strong wind | 83.4 | $1M | ||
| Hurricane | 74.3 | $706K | ||
| Tornado | 33.7 | $499K | ||
| Heat wave | 44.7 | $225K | ||
| Lightning | 53.4 | $208K | ||
| Cold wave | 20.8 | $188K | ||
| Winter weather | 79.9 | $165K | ||
| Earthquake | 43.6 | $149K | ||
| Hail | 9.8 | $24K | ||
| Ice storm | 19.9 | $13K | ||
| Landslide | 64.6 | $3K | ||
| Wildfire | 10.4 | $3K | ||
| Avalanche | 33.5 | $108 |
Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is relatively high and community resilience is relatively high in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included Union County. 2020s bar runs to November 2026.
By type
Most recent
Show all 16
Pennsylvania also had 7 statewide declarations that did not name single counties.
Storm history since 1967
Tornado risk by county ›The National Weather Service has logged 187 storm reports in Union County since 1967, with 3 deaths and 22 injuries and about $51.9 million in reported damage. The strongest on record here was an F3 tornado on May 31, 1985.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| May 31, 1985 | F3 | – | 20 / 2 |
| Apr 14, 2019 | EF1 | Lochiel | 0 / 0 |
| Sep 4, 2001 | F1 | Lewisburg | 0 / 0 |
| Aug 20, 2015 | EF1 | Dice | 0 / 0 |
| Jul 2, 2023 | EF1 | Mifflinburg | 0 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| May 31, 1985 | Tornado | – | $25M |
| Jun 20, 1996 | Thunderstorm Wind | Loganton | $15M |
| Sep 7, 1999 | Flash Flood | East Portion | $10M |
| Sep 7, 2011 | Flood | Lewisburg | $800K |
| Jun 7, 1999 | Thunderstorm Wind | West Milton | $150K |
| Aug 20, 1999 | Flash Flood | Lewisburg | $100K |
Source: NOAA Storm Events Database, county-based reports through Jun 6, 2026. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.
Hurricanes and tropical storms
Hurricane risk by county ›Since 1876, 1 hurricane and 7 tropical storms have passed within 65 miles of the center of Union County, 2 of them since 1950. The strongest was an unnamed hurricane in 1878, with top winds near 85 mph about 63 miles away.
Strongest storms nearby
| Date | Storm | Strength | Closest |
|---|---|---|---|
| Oct 23, 1878 | Unnamed | Category 1, 85 mph | 63 mi |
| Oct 14, 1893 | Unnamed | Tropical storm, 70 mph | 45 mi |
| Sep 18, 1876 | Unnamed | Tropical storm, 60 mph | 63 mi |
| Aug 29, 1949 | Unnamed | Tropical storm, 60 mph | 62 mi |
| Aug 13, 1955 | Connie | Tropical storm, 55 mph | 64 mi |
| Aug 24, 1933 | Unnamed | Tropical storm, 55 mph | 47 mi |
Most recent storms
| Date | Storm | Strength | Closest |
|---|---|---|---|
| Sep 6, 1979 | David | Tropical storm, 45 mph | 46 mi |
| Aug 13, 1955 | Connie | Tropical storm, 55 mph | 64 mi |
| Aug 29, 1949 | Unnamed | Tropical storm, 60 mph | 62 mi |
| Aug 24, 1933 | Unnamed | Tropical storm, 55 mph | 47 mi |
| Oct 14, 1893 | Unnamed | Tropical storm, 70 mph | 45 mi |
| Aug 21, 1888 | Unnamed | Tropical storm, 45 mph | 42 mi |
Source: NOAA National Hurricane Center best-track records (HURDAT2), 1851 to 2025 for the Atlantic and 1949 to 2025 for the eastern Pacific. A storm counts if its track passed within 65 miles of the county's center while it was a tropical storm or hurricane. Strength is the storm's top sustained wind at that point, not the wind measured in the county. Older storms over the open sea were sometimes missed.
Flood insurance in Union County
Check your address flood zone ›National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.
Homes in Union County
Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 16,205 housing units.
Compare in Pennsylvania
All 67 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Philadelphia County | Inland flooding | |
| Allegheny County | Inland flooding | |
| Montgomery County | Inland flooding | |
| Bucks County | Inland flooding | |
| Delaware County | Inland flooding | |
| Lancaster County | Inland flooding | |
| Chester County | Inland flooding | |
| York County | Inland flooding |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Centre County | 13 | |
| Lycoming County | 19 | |
| Northumberland County | 17 | |
| Mifflin County | 15 | |
| Snyder County | 15 | |
| Clinton County | 13 |
Common questions about Union County
What is the biggest natural hazard in Union County?
Inland flooding has the highest expected yearly losses in Union County, about $11.1 million a year in FEMA's estimate. Strong wind is second at $1.2 million.
How many federal disasters has Union County had?
Union County has been included in 16 federal disaster or emergency declarations for natural events since 1972, including 11 major disasters. The most recent was Tropical Storm Debby in September 2024.
Is Union County a high-risk place to live?
Its overall rating is Relatively Low, 50th highest of 67 in Pennsylvania. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.
Do I need flood insurance in Union County?
Standard home insurance does not cover flooding. About 1 in 50 homes in Union County has federal flood insurance. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.
How many tornadoes has Union County had?
NOAA records list 12 tornadoes in Union County since 1950. The strongest was an F3 tornado on May 31, 1985. The weather service has also logged 15 hail reports and 32 floods here.
How many hurricanes have hit Union County?
NOAA's hurricane records show 1 hurricane and 7 tropical storms passing within 65 miles of the center of Union County. The strongest was an unnamed hurricane in 1878, with winds near 85 mph.
Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.