When Is It Too Windy for a Bounce House? Bay Area Wind by Month

The data

Weekend party hours above 15 mph, by month

Each square is the share of weekend readings between 10 a.m. and 6 p.m. in that month, over nine years, when the sustained wind or a gust was above 15 mph, the low end of the 15 to 25 mph range the US Consumer Product Safety Commission gives for bounce houses (CPSC, 2019). At SFO more than half of party hours from April to September were that windy; over the whole year San José, Hayward and Livermore had about a third of SFO’s share.

Summary by airport, 2016-2024: weekend readings from 10 a.m. to 6 p.m. and the share with sustained wind or gusts above each threshold. Monthly figures for every threshold are in the CSV.

Download the full table (CSV), free to reuse under CC BY 4.0 with credit to Bay Area Kids Rentals.

Time of day

Mornings were calmer than afternoons at every airport

At all five airports the share of readings above 15 mph was lowest in the 10 a.m. hour and highest at 3 or 4 p.m., about 3 to 5 times the morning share. These figures are all months together.

Stronger wind

Weekend party hours above 20 mph, by month

The CPSC range runs from 15 to 25 mph. At 20 mph, SFO stands apart: from April to August, 33% to 46% of its weekend party hours were that windy, while no other airport passed 17% in any month.

Strongest wind

Weekend party hours above 25 mph, by month

Above 25 mph, the top of the CPSC range, the pattern changes: February, when winter storms pass through, had the most such hours at 4 of the 5 airports. At SFO, June was higher.

For parents

What this means for parents

• If you can, plan a morning party. At every airport we studied, readings at 10 a.m. were the least likely to top 15 mph, and by mid-afternoon the share was about 3 to 5 times higher.
• San Francisco and the north Peninsula, April to September: at SFO more than half of weekend party hours in each of those months topped 15 mph. Have a plan B: a sheltered spot, a morning slot, or rentals with no blower such as soft play and ball pits.
• In winter, watch for storms. February had the most hours above 25 mph at four of the five airports. Check the forecast a few days out and again the day before.
• Airport wind is not your backyard. Airports are wide, open and flat. A yard with fences and trees can be calmer; a hilltop, a shoreline park or a gap between buildings can be windier. Use these numbers to choose a date and time, then check the hourly forecast for your address, gusts included.
• On the day, the bounce house’s own limit decides. The US CPSC says maximum wind speed should be no more than 15 to 25 mph and to follow the maker’s instructions (CPSC, 2019). The limit for that unit and the setup crew’s call on site decide whether it goes up, not these averages. More in how windy is too windy for a bounce house.

How we did it

Method, sources and limits

We used every routine hourly observation (NOAA report type FM-15) from five airport weather stations in NOAA’s Local Climatological Data, 2016 through 2024: Oakland, San Francisco, San José, Hayward and Livermore. NOAA’s files for 2025 end in late August, so we kept the nine complete years.

Party hours are Saturdays and Sundays, readings from 10:00 a.m. to 5:59 p.m. Pacific clock time (daylight saving included), eight readings a day: 37,432 readings in all, about 78 weekend days per month at each airport. A reading counts as above a threshold when the sustained speed or the reported gust is above it, in whole mph as NOAA publishes them. 108 readings without a usable wind speed were left out.

We used 15, 20 and 25 mph because the US CPSC says maximum wind speed for a bounce house should be no more than 15 to 25 mph. The right limit for any one unit is its manufacturer’s.

Independent check: we recomputed all 315 shares from a different NOAA product, the Integrated Surface Database hourly files on NOAA’s open-data bucket (wind in metres per second, times in UTC), converted to whole knots and then whole mph. All agreed within 0.4 percentage points, and every figure quoted in the headline and key numbers matched exactly.

Sources

• NOAA NCEI Local Climatological Data, Oakland International Airport (station 72493023230), hourly, 2016-2024 (link shows 2024)
• NOAA NCEI Local Climatological Data, San Francisco International Airport (station 72494023234), hourly, 2016-2024 (link shows 2024)
• NOAA NCEI Local Climatological Data, San José Mineta International Airport (station 72494523293), hourly, 2016-2024 (link shows 2024)
• NOAA NCEI Local Climatological Data, Hayward Executive Airport (station 72585093228), hourly, 2016-2024 (link shows 2024)
• NOAA NCEI Local Climatological Data, Livermore Municipal Airport (station 72492723285), hourly, 2016-2024 (link shows 2024)
• NOAA Integrated Surface Database, global-hourly files (independent check), 2016-2024. Link shows SFO 2024; other files follow the same pattern
• US Consumer Product Safety Commission, “Don’t Get Swept Away” (news release), August 8, 2019. Wind guidance of 15 to 25 mph

Limits

• Airports stand in for wide areas. The coast, the North Bay and the hills are not covered, and wind on your street can differ a lot from the nearest airport.
• Each reading is one observation near the end of the hour, not a record of the whole hour. A calm reading does not mean there were no gusts that hour.
• About 78 weekend days per month per airport over nine years: a few stormy weekends can move a winter month by several points.
• These are planning odds, not a forecast and not a safety rating. Whether a bounce house goes up depends on the wind on the day, the unit’s limit and the crew.
• We did not use manufacturer manuals or the ASTM F2374 standard, which is not freely published; the thresholds follow the CPSC’s public guidance.

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