Mosquito forecast
Gainesville Mosquito Forecast
Today's mosquito activity in Gainesville, the week ahead, and what to do about it. Updated hourly.Today's mosquito activity in Gainesville on a 0–100 Bite Index, the week ahead, and what to do about it. Built from the rain and temperature that drive Alachua County's trap counts; updated hourly.
Bite Index · Sunday, November 8
High
High mosquito activity in Gainesville today and easing through the week. Cover up or use repellent after 6 pm.
Bites within a few minutes outdoors at dusk. Repellent or long sleeves pay off.
Worse than a typical November in Alachua County (usually around 25).
- It's the edge of the season; warm weeks like this one keep it going past the calendar.
- Tonight: a 69°F evening, light wind — good flying weather for mosquitoes.
- A two-week average of 72°F keeps populations growing, just more slowly than midsummer.
The week ahead
Each day's Bite Index, from this week's weather and the rain that is still hatching. Forecast days get less certain as the week goes on.
- Today46HighHigh81°/51°dry
- Mon47HighHigh80°/59°dry
- Tue47HighHigh82°/56°dry
- Wed47HighHigh78°/66°dry
- Thu46HighHigh79°/65°dry
- Fri25Mod.Moderate68°/48°dry
- Sat20LowLow58°/40°dry
Protect tonight
Use repellent for any time outside after about 6 pm.
- 20% picaridin or 20–30% DEET for the evening; follow the label's reapplication window.
- Long sleeves and pants in light colors cut bites roughly in half on their own.
- Skip the yard work at dusk: the hour around sunset is the heaviest biting of the day.
Why Gainesville's mosquitoes do what they do
Gainesville is a city of prairies, sinkholes and spring-fed wetlands in the middle of North Florida, with heavy summer rain and the tree canopy to hold its humidity. The city's Mosquito Control program runs traps and sentinel chickens and sprays by zone; the health department issued a mosquito-borne illness advisory in 2026 after chickens tested positive.
- Paynes Prairie and the sinkholes: vast wetland habitat on the city's doorstep.
- Canopy: shade and leaf litter favor the daytime-biting Asian tiger mosquito.
- Heavy summer rain: June through September storms keep containers and ditches full.
- Sentinel chickens: the city's flocks detect West Nile and EEE before people get sick.
A typical year in Alachua County
What the Bite Index typically reads here each month, from Alachua County's 30-year climate normals run through the same model as today's number. The month you're in is marked; the season map shows the same long-run picture for every county.
- JJanuary: 2
- FFebruary: 2
- MMarch: 19
- AApril: 51
- MMay: 72
- JJune: 86
- JJuly: 86
- AAugust: 86
- SSeptember: 86
- OOctober: 68
- NNovember: 25
- DDecember: 3
Local surveillance and West Nile virus
The Bite Index measures nuisance biting, not disease. Alachua County's health department traps and tests mosquitoes through the season and publishes positive West Nile pools by ZIP code. When your ZIP has an active advisory, follow it regardless of today's number.
- City of Gainesville — Mosquito Control
Trapping, sentinel chickens, larviciding and spraying across the city; posts spray schedules.
- Alachua County / DOH-Alachua — Mosquito-borne illness advisory
The county's 2026 advisory after sentinel chickens tested positive.
How the Bite Index is scored
The index is a model of conditions, not a mosquito count. Warmth and water set the size of the population, tonight's weather sets how much of it flies, and the season and local reports adjust the result. Every factor and today's value for it is listed here so you can check the number yourself. Warmth and Water are exactly the climate core of our county-level mosquito season map; the map shows that core on 30-year normals for every county, and “typical for this month” is the same model run on this county's normals, so the comparison is like for like.
WWater
Rain over the egg-to-adult window (0.6 in. between Oct 23 and Oct 31), expressed as a monthly rate on the same wetness curve the season map uses. At summer temperatures eggs become biting adults in about a week, so today's mosquitoes are last week's rain. Cool weather stretches the window; hot dry days shrink it. Irrigation, creeks and pools keep a 35% floor even in a drought.
TWarmth
The trailing two-week average temperature on the season map's curve: nothing below 50°F, full speed at 78–88°F, a small penalty in extreme heat. Multiplied with Water, so a cool fortnight caps the index however wet it has been.
ATonight
Whether the population that exists will actually fly and bite this evening: dusk temperature (65–85°F is ideal), wind (they stop flying around 10 mph), humidity, and rain around sunset. Scales the index between half and full.
GGround truth
A nudge from local trap counts and reports when we have them. For Gainesville this is neutral today; the health department's surveillance is linked above and will feed this factor as we wire it in.
SSeason gate
A multiplier from the calendar: fully open in the city's season months, half-open in the shoulder months, nearly closed in deep winter unless the week is warm. Below a 50°F weekly average the index is simply 0.
index = 100 × S × [T × (0.35 + 0.65·W)] × (0.5 + 0.5·A) × (1 + 0.15·G)
Bands: Low 0–20 · Moderate 21–40 · High 41–60 · Very High 61–80 · Severe 81–100. Weather is from Open-Meteo (observations and the 7-day forecast), refreshed hourly. The lag and temperature thresholds follow published work on Culex and Aedes development (Rueda et al. 1990; Cornell NRCC degree-day emergence; JAMCA 2024 on rainfall two to four weeks before trap peaks).
Questions people ask about mosquitoes in Gainesville
- When is mosquito season in Gainesville?
- April through October, peaking from June through September. A short winter lull from December to February.
- Why does Gainesville spray after hurricanes?
- Storm rain floods the prairies and yards at once, and a week or two later the city gets a brood; after Debby in 2024 the city ran extra spraying for that reason. The index shows the same lag.
- Is West Nile virus a risk in Gainesville?
- Yes. The city's sentinel chickens convert most years and the county issued an advisory in 2026. Those advisories are authoritative; follow them over the index.
- Where does this forecast's data come from?
- Open-Meteo weather for central Gainesville, scored by our documented model and compared with Alachua County's climate normals. Not a trap count.
Also covers Alachua, Newberry, High Springs, Micanopy, Archer, Hawthorne, Paynes Prairie, Devil's Millhopper: the forecast point is central Gainesville, and conditions within about 30 miles track it closely. Weather fetched Nov 8, 5:28 PM local time.