Concrete Pouring Weather in San Bernardino, CA: 10-Day Windows & Best Months
The concrete pouring season in San Bernardino runs October through June — 9 months averaging at least 8 workable days by NOAA 1991–2020 normals. The single best month is October, averaging 28 days that clear every check — highs of 83°F, lows near 53°F, and a 8% daily rain chance. Below: today through day 10 against the label rules, then the year at a glance.
GOOD — every label check passes MARGINAL — one soft fail NO — hard fail or several soft
The rules this check uses
The San Bernardino strip runs on these rows — bagged-mix consensus for DIY-scale work, ruled by the 48-hour freeze check. Structural pours answer to an engineer and ACI, not to this page.
| Check | Threshold | Why it matters |
|---|---|---|
| Air temperature | 40–90°F — ideal 50–85°F | The film (or mix) chemistry runs on temperature — both while you work and for the first hours after. |
| Overnight low | ≥40°F during the first 48 h | Curing continues after dark; the first night can undo a perfect afternoon. |
| Dry before | no soaking (≥1.0") in the prior 24 h | Checked backward from your start hour using the two look-back days in the forecast data. |
| Dry after | <0.1" rain for 6 h after (12 h light rain after finishing still risks surface marks) | The engine sums forecast rain hour by hour through the cure window for San Bernardino. |
| Wind | ≤20 mph (rapid surface drying up to 28 mph) | Hot wind pulls bleed water out faster than the slab can handle. |
Always follow your product label — formulas vary. The table above is the typical range across major manufacturers, not a promise about your can.
Best months for concrete pouring in San Bernardino
| Month | Avg high | Avg low | Rain odds/day | Workable days | |
|---|---|---|---|---|---|
| January | 67°F | 41°F | 22% | 24 | |
| February | 67°F | 42°F | 26% | 21 | |
| March | 71°F | 45°F | 21% | 25 | |
| April | 76°F | 48°F | 14% | 26 | |
| May | 80°F | 52°F | 8% | 28 | |
| June | 88°F | 56°F | 3% | 18 | |
| July | 95°F | 62°F | 2% | 0 | |
| August | 96°F | 63°F | 2% | 0 | |
| September | 92°F | 60°F | 4% | 7 | |
| October | 83°F | 53°F | 8% | 28 | |
| November | 75°F | 45°F | 13% | 26 | |
| December | 66°F | 40°F | 20% | 12 |
Figure 216 workable days a year in San Bernardino, spread across October through June. Shoulder months turn on the overnight rule: an afternoon at 83°F passes, but the 40°F night floor is what actually opens the season in October. The California table ranks every listed city by the same math.
July here fails on heat, not rain: the average high of 95°F sits over the 90°F label ceiling, and 31 of 31 days typically top 90°F. Midsummer work moves to dawn or waits for October.
The rain odds swing hard across the year — 2% of days in July up to 26% in February. Season the plan accordingly: prep in the wet months, apply in the dry ones.
Sealing the same driveway later? Sealcoating in San Bernardino wants warmer nights (50°F+) than the pour did.
Source honesty: every monthly figure on this page is the 1991–2020 normal at Redlands, Ca Us, 14.8 km from San Bernardino's center — your block's shade lines and wind exposure sit on top of that baseline. Scoring details are on the methodology page.
San Bernardino by the numbers
- Hottest month: August — 96°F average high, 31 days topping 90°F.
- The cold floor is December at 66°F afternoons and 40°F overnight.
- Measurable rain: February leads at 26% of days; July is the quiet end at 2%.
- Bottom line for San Bernardino: roughly 216 workable concrete pouring days a year.
Prep checklist
- Clear the 48-hour rule first: two nights over 40°F. October opens that door in San Bernardino; December (40°F average lows) slams it.
- Nothing gets mixed until the site is staged — braced forms, compacted damp base, rinsed tools, a second pair of hands.
- Cut plastic sheeting and weight it at the pour's edge — San Bernardino sees rain on 8% of October days, and the 6-hour rule doesn't negotiate.
- Mix to a low slump — thick oatmeal, not soup; extra water now is a weak surface forever.
- Timing beats muscle — screed wet, float at the dull stage, and never chase bleed water with a trowel.
- Edge and joint with an edger + float set — control joints every 2–3 slab-thicknesses in feet.
- Hold the moisture in (sheeting or misting); when June nights dip toward 56°F, a curing blanket is the difference.
- Keep feet off 24–48 hours and cars off a week; structural pours follow the engineer and ACI, full stop.
Gear that saves a window
Transparency note: gear links here become affiliate links only when the program is enabled — today they are plain references. See the affiliate disclosure.
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IR surface thermometer
Track slab temperature, not just the forecast.
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Edger + float set
Rounded edges and a flat surface before it sets.
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Concrete mix
An 80-lb bag yields about 0.6 cu ft — do the math twice.
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Curing blanket
Holds heat through cold nights in the critical 48 hours.
FAQ
What temperature is too cold to pour concrete?
The line is a 40°F low inside the first 48 hours; an actual freeze (32°F) physically damages young concrete. San Bernardino's December nights average 40°F — firmly out — while October nights hold near 53°F. Small pours only; structural work follows engineer/ACI specs.
Can you pour concrete before rain?
The engine wants 6 protected hours; light rain later actually feeds the cure. With 26% rain-day odds in February versus 2% in July, San Bernardino's dry-season pours barely think about this rule and wet-season pours live by the radar. For small DIY pours; structural schedules follow ACI.
How long does concrete need to be protected from freezing?
Keep it above freezing for at least the first 48 hours (the engine calls any sub-40°F low in that window a NO). In San Bernardino that rules out roughly December-adjacent months entirely and makes shoulder-season pours a two-night forecast decision. DIY scope; anything structural follows engineer/ACI cold-weather practice.
Is it OK to pour concrete in hot weather?
To a 90°F high, yes — with shade, cool mix water, a damp subgrade, and a dawn start. Above 90°F the surface sets while the core is plastic and shrinkage cracks map the slab. San Bernardino averages 31 such days in July, which is why summer pours here move to first light.
How long before you can drive on new concrete?
A week before tires, 24–48 hours before feet — at October-typical San Bernardino temperatures (83°F highs). When nights slide toward 40°F, add days: cure speed is temperature. Early loads print permanent marks; the bag's cure table wins every argument.
Best season for concrete work in San Bernardino?
October through june — the months with 40°F+ nights, sub-90°F days, and manageable rain. October leads at 28 workable days; December bottoms out near 12.
Related
Other projects in San Bernardino
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- Exterior Painting in San Bernardino
- Driveway Sealing in San Bernardino
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- All outdoor project weather in San Bernardino
Concrete Pouring nearby
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- Fontana, CA
- Jurupa Valley, CA
- Riverside, CA
- Rancho Cucamonga, CA
- Moreno Valley, CA
- Hesperia, CA
- Ontario, CA
Guides
Climatology: NOAA 1991–2020 normals via REDLANDS, CA US (14.8 km from San Bernardino center, elevation 1410 ft); live outlook by Open-Meteo.