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Concrete Pouring Weather in Kailua, HI: 10-Day Windows & Best Months

By NOAA 1991–2020 normals, Kailua keeps a concrete pouring window open in all 12 months — a year-round season few US cities match. The single best month is May, averaging 19 days that clear every check — highs of 81°F, lows near 70°F, and a 37% 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 Kailua 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.

Typical label thresholds for concrete pouring — the ruleset behind every Kailua verdict above.
CheckThresholdWhy 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 Kailua.
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 Kailua

Kailua's calendar, scored: each month's days passing the temperature rules, discounted by that day's historical rain odds (NOAA 1991–2020). Not a forecast.
MonthAvg highAvg lowRain odds/dayWorkable days 
January 78°F 65°F 51% 15
February 78°F 65°F 47% 15
March 78°F 67°F 48% 16
April 80°F 69°F 43% 17
May 81°F 70°F 37% 19
June 83°F 73°F 39% 18
July 84°F 74°F 46% 17
August 85°F 74°F 43% 18
September 85°F 74°F 44% 17
October 84°F 73°F 47% 17
November 82°F 70°F 53% 14
December 79°F 68°F 58% 13

Kailua's calendar never really closes: even February, the leanest month, averages 15 workable days against the 40–90°F rules. The 10-day strip above matters more here than any season chart. The Hawaii table ranks every listed city by the same math.

Summer's enemy here is the rain gauge: July sees measurable rain on 46% of days, so back-to-back dry 6-hour cure windows come in streaks, not on schedule. The 10-day strip earns its keep in December (58% wet days).

The rain odds swing hard across the year — 37% of days in May up to 58% in December. Season the plan accordingly: prep in the wet months, apply in the dry ones.

Sealing the same driveway later? Sealcoating in Kailua wants warmer nights (50°F+) than the pour did.

Source honesty: every monthly figure on this page is the 1991–2020 normal at Waimanalo Exp F 795.1, Hi Us, 6.9 km from Kailua's center — your block's shade lines and wind exposure sit on top of that baseline. Scoring details are on the methodology page.

Kailua by the numbers

Prep checklist

  1. Clear the 48-hour rule first: two nights over 40°F. May opens that door in Kailua; February (65°F average lows) slams it.
  2. Nothing gets mixed until the site is staged — braced forms, compacted damp base, rinsed tools, a second pair of hands.
  3. Cut plastic sheeting and weight it at the pour's edge — Kailua sees rain on 37% of May days, and the 6-hour rule doesn't negotiate.
  4. Mix to a low slump — thick oatmeal, not soup; extra water now is a weak surface forever.
  5. Timing beats muscle — screed wet, float at the dull stage, and never chase bleed water with a trowel.
  6. Edge and joint with an edger + float set — control joints every 2–3 slab-thicknesses in feet.
  7. Hold the moisture in (sheeting or misting); when May nights dip toward 70°F, a curing blanket is the difference.
  8. 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.

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. Kailua's February nights average 65°F — firmly out — while May nights hold near 70°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 58% rain-day odds in December versus 37% in May, Kailua'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 Kailua that rules out roughly February-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. Kailua averages 0 such days in July — rarely the binding constraint here.

How long before you can drive on new concrete?

A week before tires, 24–48 hours before feet — at May-typical Kailua temperatures (81°F highs). When nights slide toward 65°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 Kailua?

The table above says May, June and August: enough warmth for the 48-hour cure, short of the 90°F ceiling. For small DIY pours that's the whole answer; structural pours schedule to engineer/ACI requirements, not to a best-months chart.

Other projects in Kailua

Concrete Pouring nearby

Guides

Climatology: NOAA 1991–2020 normals via WAIMANALO EXP F 795.1, HI US (6.9 km from Kailua center, elevation 64 ft); live outlook by Open-Meteo.