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Union County, Pennsylvania

Natural disaster risk, federal disaster history and flood insurance facts.

Relatively Low overall risk
50th of 67highest risk in Pennsylvania
$14Mexpected losses a year
16federal declarations
1 in 50homes with flood insurance
Photo: U.S. Geological Survey, public domain

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

$11.1 million a yearExpected losses. Damaging events about once a year.
  • 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.

Strong wind

Moderate
$1.2 million a yearExpected losses. Damaging events about 3 times a year.
  • Secure outdoor furniture and trash bins before storms.
  • Have trees near the house checked.
$705,718 a yearExpected losses. Damaging events about once every 20 years.
  • 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.
HazardRatingScoreExpected loss a year
Inland floodingLow71.8
$11M
Strong windModerate83.4
$1M
HurricaneLow74.3
$706K
TornadoLow33.7
$499K
Heat waveLow44.7
$225K
LightningLow53.4
$208K
Cold waveVery Low20.8
$188K
Winter weatherModerate79.9
$165K
EarthquakeVery Low43.6
$149K
HailVery Low9.8
$24K
Ice stormVery Low19.9
$13K
LandslideLow64.6
$3K
WildfireVery Low10.4
$3K
AvalancheVery Low33.5
$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

Flood6
Severe Storm3
Hurricane3
Snowstorm2
Tornado1
Tropical Storm1

Most recent

Sep 11, 2024Tropical Storm DebbyMajor disaster
Oct 29, 2012Hurricane SandyEmergency
Sep 12, 2011Tropical Storm LeeMajor disaster
Sep 8, 2011Remnants of Tropical Storm LeeEmergency
Sep 10, 2005Hurricane KatrinaEmergency
Sep 19, 2004Severe Storms and Flooding Associated With Tropical Depression FrancesMajor disaster
Sep 19, 2004Tropical Depression IvanMajor disaster
Mar 14, 2003SnowEmergency
Sep 22, 1999Tropical Depression Dennis PaMajor disaster
Jan 21, 1996Severe Storms and FloodingMajor disaster
Show all 16
Jan 13, 1996Blizzard of 96Major disaster
Mar 10, 1994Severe Winter StormsMajor disaster
Mar 16, 1993Severe Snowfall & Winter StormEmergency
Jun 3, 1985Severe Storms, High Winds & TornadoesMajor disaster
Sep 26, 1975Severe Storms, Heavy Rains & FloodingMajor disaster
Jun 23, 1972Tropical Storm AgnesMajor disaster

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.

12tornadoes
15hail reports, largest 2.5 inches
128damaging thunderstorm winds
32floods and flash floods

Strongest tornadoes

DateStrengthNearHurt / killed
May 31, 1985F3–20 / 2
Apr 14, 2019EF1Lochiel0 / 0
Sep 4, 2001F1Lewisburg0 / 0
Aug 20, 2015EF1Dice0 / 0
Jul 2, 2023EF1Mifflinburg0 / 0

Most damaging storms

DateTypeNearDamage
May 31, 1985Tornado–$25M
Jun 20, 1996Thunderstorm WindLoganton$15M
Sep 7, 1999Flash FloodEast Portion$10M
Sep 7, 2011FloodLewisburg$800K
Jun 7, 1999Thunderstorm WindWest Milton$150K
Aug 20, 1999Flash FloodLewisburg$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.

1hurricanes
0major hurricanes (Category 3+)
7tropical storms
1979most recent: David

Strongest storms nearby

DateStormStrengthClosest
Oct 23, 1878UnnamedCategory 1, 85 mph63 mi
Oct 14, 1893UnnamedTropical storm, 70 mph45 mi
Sep 18, 1876UnnamedTropical storm, 60 mph63 mi
Aug 29, 1949UnnamedTropical storm, 60 mph62 mi
Aug 13, 1955ConnieTropical storm, 55 mph64 mi
Aug 24, 1933UnnamedTropical storm, 55 mph47 mi

Most recent storms

DateStormStrengthClosest
Sep 6, 1979DavidTropical storm, 45 mph46 mi
Aug 13, 1955ConnieTropical storm, 55 mph64 mi
Aug 29, 1949UnnamedTropical storm, 60 mph62 mi
Aug 24, 1933UnnamedTropical storm, 55 mph47 mi
Oct 14, 1893UnnamedTropical storm, 70 mph45 mi
Aug 21, 1888UnnamedTropical storm, 45 mph42 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 ›
2%of homes have federal flood insurance (231 policies)
16.6%of homes in mapped high-risk flood zones are insured
$11.7 millionpaid on 927 flood claims since 1978
2004costliest year, with $3.2 million paid

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

$240,100median home value (Pennsylvania $254,500, US $332,700)
1974median year homes were built (Pennsylvania 1965, US 1980)
58%of homes built before 1980, before many modern wind, quake and flood building rules
8.2%of homes are mobile homes, which are the least safe in tornadoes and high winds

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 countiesOverall riskTop hazard
Philadelphia CountyVery HighInland flooding
Allegheny CountyHighInland flooding
Montgomery CountyHighInland flooding
Bucks CountyHighInland flooding
Delaware CountyModerateInland flooding
Lancaster CountyHighInland flooding
Chester CountyModerateInland flooding
York CountyModerateInland flooding

Neighboring counties

CountyOverall riskDeclarations
Centre CountyLow13
Lycoming CountyLow19
Northumberland CountyLow17
Mifflin CountyLow15
Snyder CountyLow15
Clinton CountyLow13

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.