Follow Us
*Disclaimer: HeyAllergy® provides all clinical services furnished to patients in California, Florida, Texas, Illinois, Nevada, Pennsylvania. In New York, clinical services are furnished by Hey Allergy Medicine.
Real-time pollen data for League City — updated daily.
Mountain cedar (Ashe juniper) pollen arrives from the Hill Country on northwest winds in January, causing cedar fever with flu-like symptoms. Live oak is League City's signature tree allergen, peaking March through April with heavy pollen production from the city's extensive canopy. Pine, ash, elm, pecan, and mulberry contribute additional pollen through spring. Sweetgum and sycamore add to the mix in riparian areas along Clear Creek and the bayous.
Bermuda grass dominates maintained lawns, parks, and the numerous golf courses in the Clear Lake area. Johnson grass is the primary wild grass allergen in Southeast Texas, growing aggressively along roadsides and undeveloped land. Bahia grass contributes from surrounding pastureland. The grass pollen season is exceptionally long — April through October — due to League City's warm, humid Gulf Coast climate. Rain-fueled growth keeps grass pollen production vigorous throughout the extended season.
Ragweed is the dominant fall allergen, with a single plant producing up to one billion pollen grains per season. Pigweed, marsh elder, and lamb's quarters add to the weed burden. The flat coastal prairie allows weed pollen to travel long distances on Gulf breezes. League City's warm autumn extends weed pollen season into late November — significantly later than northern cities.
Mold is one of League City's most persistent allergens. Clear Creek, Dickinson Bayou, Magnolia Bayou, and multiple secondary waterways produce continuous mold from decomposing vegetation and standing water. Gulf humidity averaging 75%+ sustains mold growth even during drier months. Post-hurricane moisture in homes creates chronic indoor mold. Alternaria, Aspergillus, Cladosporium, and Penicillium are common both outdoors and inside homes.
Dust mites thrive aggressively in League City's Gulf Coast humidity. Pet dander and cockroach allergens are significant perennial triggers. Homes near bayou corridors experience higher indoor humidity that feeds both dust mites and indoor mold. AC systems that run continuously for 8+ months require frequent filter changes and duct cleaning to prevent allergen recirculation.
Severity: Moderate. Brief cold fronts provide League City's only meaningful allergy relief, temporarily dropping humidity and clearing pollen. However, mountain cedar pollen arrives from Central Texas in January, causing cedar fever with flu-like symptoms. Mold persists along bayou corridors. Dust mites remain active in the warm, humid indoor environment.
Severity: Moderate to High. Cedar pollen fades as live oak, elm, ash, and pine begin pollinating. League City's extensive live oak canopy begins producing visible pollen by late February. Mold increases with winter rain. The transition from cedar to live oak can create near-continuous symptoms for residents sensitive to both.
Severity: Severe. League City's worst allergy period. Live oak pollen peaks while Bermuda and Johnson grass surge. The overlap of tree and grass pollen creates the year's most intense allergen exposure. Gulf humidity begins its summer climb, elevating mold across all bayou corridors. Rain events trigger explosive mold growth.
Severity: High (mold and indoor allergens). Summer heat and oppressive Gulf humidity keep mold at its annual peak across all waterway corridors. Grass pollen continues but begins declining. Ragweed starts in August. Hurricane season brings flooding risk and post-storm mold events. Dust mites peak in the humid indoor environment. AC systems run continuously, recirculating indoor allergens if filters aren't maintained.
Severity: High. Ragweed peaks across the coastal prairie. Mold remains elevated from summer rainfall and bayou moisture. League City's warm fall extends ragweed season into late November. Tropical weather systems can still bring flooding through November, compounding mold exposure.
League City sits on the coastal prairie between Clear Lake and Galveston Bay to the east and the bayou systems to the south and west. Gulf moisture flows inland daily, keeping humidity elevated year-round. This isn't Houston's inland humidity — it's coastal moisture amplified by proximity to 600 square miles of Galveston Bay. The result is year-round dust mite and mold conditions that exceed what inland Houston suburbs experience. Running a dehumidifier to maintain indoor humidity below 50% is essential but difficult during League City's long humid season.
League City's 55 square miles are threaded with waterways: Clear Creek to the north, Dickinson Bayou to the southwest, Magnolia Bayou, Chigger Bayou, and multiple secondary drainage channels. These riparian corridors produce mold year-round from decomposing vegetation and standing water. After rainfall, mold spore counts spike along these corridors and are carried into neighborhoods by Gulf breezes. If you live within a quarter mile of any bayou or creek in League City, expect elevated mold counts compared to inland neighborhoods.
Hurricane Harvey (2017) caused widespread flooding throughout the Clear Creek and Dickinson Bayou watersheds. League City led a comprehensive watershed study after Harvey to address flood mitigation. If you purchased or rented a home in League City after 2017, hidden post-flood mold in walls, subfloors, and ductwork is a possible contributor to persistent indoor allergy symptoms. Hurricane Ike (2008) and Hurricane Beryl (2024) also caused damage in the area. Professional mold inspection is recommended for any home that may have experienced water intrusion.
Mountain cedar (Ashe juniper) pollen from the Texas Hill Country travels hundreds of miles on northwest winds and reaches the Gulf Coast, including League City. Cedar fever peaks in January and early February with symptoms that mimic influenza: severe congestion, headache, fatigue, and body aches. If you feel sick every January but have no actual fever, cedar pollen is the likely cause. Pre-medicate when cedar counts are forecast as high.
League City is famous for its heritage live oak trees — planted as early as 1907 when railroad flatcars of oaks were distributed to residents. These iconic Butler Oaks and thousands of newer live oaks throughout the city's planned communities produce heavy pollen from March through April. Live oak pollen is one of the most significant tree allergens in the Houston-Galveston region. During peak weeks, the yellow-green pollen is visible on cars and outdoor surfaces.
League City's combination of Gulf Coast humidity, bayou-corridor mold, long grass pollen season, and imported cedar pollen means there is no true allergy-free period. Standard HVAC filters (MERV 8) allow most pollen and mold spores to pass through. Upgrading to MERV 13 filters — and changing them every 30–45 days during spring and fall — significantly reduces indoor allergen levels.
March through May is worst for tree and grass pollen overlap. January brings cedar fever from Central Texas. August through November adds ragweed. Mold is elevated year-round from bayou corridors and Gulf humidity. League City has no true allergy-free season.
Yes. Mountain cedar pollen from the Texas Hill Country travels on northwest winds and reaches the Gulf Coast. Cedar fever peaks in January with symptoms mimicking the flu: severe congestion, headache, fatigue, and body aches. If you feel sick every January without actual fever, cedar pollen is likely the cause.
League City's proximity to Galveston Bay keeps humidity higher than inland suburbs. This elevated moisture supports year-round dust mites and mold that inland areas don't sustain. The bayou network adds concentrated mold corridors through residential neighborhoods. And the coastal prairie's flat terrain allows pollen to travel great distances on Gulf breezes.
Yes. Clear Creek, Dickinson Bayou, Magnolia Bayou, and secondary drainage channels produce mold year-round. Properties near these waterways experience elevated mold counts, especially after rainfall when decomposing vegetation releases spores into the air.
Yes. HeyAllergy provides telemedicine appointments with board-certified allergists licensed in Texas. No waitlist. Available throughout the Houston-Galveston region including League City, Clear Lake, Webster, and Friendswood.
HeyPak® sublingual immunotherapy drops are customized based on allergy blood test results. For League City residents, this targets local cedar, live oak, Bermuda grass, ragweed, mold, and dust mite allergens specific to the Gulf Coast. Daily drops retrain your immune system with improvement in 3–6 months. Starting at $47/month.
HeyAllergy accepts Medicare and most major PPO health plans, including United Healthcare, Anthem Blue Cross, Blue Shield, Cigna, Aetna, Humana, Oscar, and Tricare. Tax ID: 85-0834175.
Almost certainly for homes that experienced flooding. Harvey caused widespread damage in the Clear Creek and Dickinson Bayou watersheds. Hidden moisture in walls and ductwork feeds mold growth for years. Professional mold inspection is recommended for any home that may have experienced water intrusion during Harvey, Ike, or Beryl.
League City occupies 55 square miles of Texas coastal prairie between Houston and Galveston, positioned where the flat grasslands transition into the marshes, bayous, and tidal waters of the Galveston Bay system. Clear Creek forms the city's northern boundary, flowing east into Clear Lake — a brackish tidal lake that empties into Galveston Bay. To the southwest, Dickinson Bayou drains through marshland toward the Gulf. Between these major waterways, smaller bayous including Magnolia Bayou and Chigger Bayou thread through residential neighborhoods. This waterway-rich geography, combined with proximity to 600 square miles of Galveston Bay, creates an allergen environment defined by coastal moisture, bayou-origin mold, and year-round humidity that distinguishes League City from inland Houston suburbs.
League City has a special relationship with live oak trees dating to 1907, when J.C. League had two railroad flatcars of live oaks delivered for residents to plant on their properties. These Butler Oaks, many still lining Main Street, established the city's tree canopy identity. Today, live oaks are ubiquitous throughout League City's planned communities and established neighborhoods. While they reduce stormwater runoff by up to 17% per tree (a significant benefit in this flood-prone area), live oaks also produce heavy pollen from March through April — one of the most significant tree allergens in the Houston-Galveston region. During peak weeks, live oak pollen coats vehicles, patios, and outdoor surfaces throughout the city.
League City's flood zones trace the paths of its many waterways: Clear Creek to the north, Dickinson Bayou to the southwest, Benson Bayou, Geisler Bayou, and numerous secondary drainage channels. These riparian corridors are year-round mold producers. Decomposing vegetation, standing water in low-lying areas, and the constant Gulf humidity create ideal conditions for mold growth along every waterway. After rainfall, which is frequent and heavy in this part of Texas, mold spore counts spike along the bayou corridors and are carried into adjacent neighborhoods by the prevailing Gulf breeze.
The Clear Creek and Dickinson Bayou watersheds experienced widespread flooding during Hurricane Harvey (2017), prompting League City to lead a $1.3 million comprehensive flood mitigation study with federal and county partners. Hurricane Ike (2008) caused substantial environmental and economic damage across the entire Galveston Bay Area. Hurricane Beryl (2024) brought wind damage with downed power lines and trees. Each flooding event introduces moisture into homes that feeds mold growth for months or years, creating a cumulative hidden mold burden across the city's housing stock.
League City's humid subtropical climate means allergy seasons overlap and blend together. Cedar fever arrives from Central Texas in January. Live oak and other tree pollen peaks March through April. Bermuda and Johnson grass pollen dominates May through September. Ragweed takes over August through November. Mold is elevated year-round from the bayou corridors and Gulf humidity. Dust mites never fully subside in the coastal moisture. The only partial relief comes in brief cold fronts during December and January that temporarily drop humidity and clear the air.
League City's coastal prairie position on Galveston Bay, bayou-threaded geography producing year-round mold, heritage live oak pollen, imported cedar fever from Central Texas, hurricane-related flooding, and relentless Gulf Coast humidity create an allergy environment that is measurably more challenging than inland Texas cities. HeyAllergy connects League City residents with board-certified allergists through telemedicine. Patients receive allergy blood testing, personalized treatment, and HeyPak® sublingual immunotherapy drops custom-formulated for the Gulf Coast's specific allergen profile. Treatment starts at $47/month. No needles, no clinic visits, no waitlist.
