September in Boise, ID: peak season for golf — great conditions and a wide playing window. Best tee times: morning before noon for the most comfortable round.
| Average September Weather | |
|---|---|
| Avg daily high | 83°F |
| Avg daily low | 55°F |
| Rainy days | 3 / mo |
| Avg peak wind | 11.1 mph |
The numbers on this page aren't abstract — they show up directly on your scorecard. September's 83°F average high sits comfortably inside the ideal 60–80°F window for most of the round, meaning you're not fighting heat fatigue on the back nine the way you might in August. The 55°F morning low does require a layer at the 6 AM tee, but temperatures climb quickly. Three precipitation days — tied with August for the second-driest of the year — translate to a high probability of dry fairways and firm turf that rewards accurate iron play. Peak wind at 11.1 mph is the second-calmest of any month, slightly calmer than August's 11.3 mph, so club selection becomes more predictable and you can actually execute the shot shape you're picturing.
The 28°F daily swing is the one variable that asks for planning. A round started in a fleece can finish in a short sleeve, and a bag that isn't ready for both will cost you comfort and focus late in the round.
Morning tee times before 8 AM mean starting near the 55°F low, so book mid-morning if you want to spend the whole round inside the ideal temperature band rather than layering up for the first four holes. With only 3 precipitation days spread across the month, last-minute bookings carry low weather risk, but September is peak season in Boise — don't count on weekend prime slots being available the same week. See how conditions rate hour by hour on our playability scale.
September's 83°F high is nine degrees cooler than August's 92°F, which materially reduces heat stress and the chance that a hot finishing stretch drains your concentration. Precipitation holds flat — both months sit at 3 days — so you're not gaining or losing much on dry-round odds moving from August into September. October drops the high another 16°F to 67°F, adds three more precip days, and offers essentially the same wind, making September the clearly stronger month for scoring conditions.
Climate normals show the long-term picture, but day-to-day weather varies. Check today's live golf weather score for Boise, ID for the current playability rating, hourly wind, temperature, and the recommended tee time window.
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September ranks as peak season, with an 83°F average high, just 3 precipitation days (tied with August at 3 precipitation days, 2nd-driest of the year), and a peak wind of 11.1 mph — the second calmest of the year. Those conditions combine to give you firm fairways, predictable ball flight, and very few weather delays. The main adjustment is managing the 28°F daily temperature swing between morning and afternoon.
The average high reaches 83°F, which is nine degrees cooler than August's 92°F and generally stays within a manageable range for a full 18 holes. Early morning rounds start near the 55°F low, so heat is rarely a concern before mid-morning. By early afternoon temperatures peak, but the dry desert air and 11.1 mph peak wind keep conditions more comfortable than the high number alone suggests.