WorkWindow

Exterior Painting Weather in Augusta, ME: 10-Day Windows & Best Months

The exterior painting season in Augusta runs May through October — 6 months averaging at least 8 workable days by NOAA 1991–2020 normals. The single best month is August, averaging 20 days that clear every check — highs of 79°F, lows near 59°F, and a 35% 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

These rows are what the Augusta strip checks hour by hour: consensus paint-can requirements, plus the low-temp-formula band the engine marks MARGINAL.

Typical label thresholds for exterior painting — the ruleset behind every Augusta verdict above.
CheckThresholdWhy it matters
Air temperature 50–90°F (low-temp formulas from 35°F) The film (or mix) chemistry runs on temperature — both while you work and for the first hours after.
Overnight low ≥35°F during the first 24 h (≥40°F preferred) Curing continues after dark; the first night can undo a perfect afternoon.
Dry before ≤0.05" rain in the prior 12 h; watch back to 24 h Checked backward from your start hour using the two look-back days in the forecast data.
Dry after <0.05" rain for 24 h after The engine sums forecast rain hour by hour through the cure window for Augusta.
Evening dew-point spread ≥5°F from 6–11 pm When air temperature meets the dew point, water condenses on your fresh work first.
Daytime humidity ≤80% Read as the daytime maximum, 10 a.m.–5 p.m.; within 3 points of the limit counts as marginal.
Wind ≤15 mph (brush only up to 20 mph) Wind dries the leading edge too fast and carries overspray.

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 exterior painting in Augusta

Augusta'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 29°F 12°F 34% 0
February 32°F 14°F 33% 0
March 41°F 23°F 36% 0
April 54°F 34°F 39% 0
May 66°F 45°F 42% 18
June 74°F 54°F 42% 18
July 80°F 60°F 39% 19
August 79°F 59°F 35% 20
September 71°F 51°F 34% 20
October 58°F 40°F 38% 11
November 46°F 30°F 38% 0
December 35°F 20°F 39% 0

Figure 105 workable days a year in Augusta, spread across May through October. Shoulder months turn on the overnight rule: an afternoon at 66°F passes, but the 40°F night floor is what actually opens the season in May. The Maine table ranks every listed city by the same math.

If the walls pass, the roof might too: roof coating in Augusta uses the same film chemistry with tighter dew and wind limits.

Source honesty: every monthly figure on this page is the 1991–2020 normal at Augusta State Ap, Me Us, 5.5 km from Augusta's center — your block's shade lines and wind exposure sit on top of that baseline. Scoring details are on the methodology page.

Augusta by the numbers

Prep checklist

  1. Find application day plus 24 dry hours with nights at 40°F+; Augusta offers that pairing most often in August (20 workable days).
  2. Scrape, then wash: loose paint and chalk go first, because latex only grips solid substrate.
  3. Give washed siding 24 hours — north walls in Augusta can need double after a May-grade soak.
  4. An ir surface thermometer settles arguments: label limits bind the wall surface, which outruns Augusta's air by 20°F+ in sun.
  5. Bare wood gets primer, stains get stain-blocker, gaps get caulk — in that order, on dry substrate.
  6. Sequence walls so you always paint in shade; midday sun skins latex before it levels.
  7. Cut in with an angled brush set, roll a wet edge, and drop the sprayer plan over 15 mph.
  8. Stop 2 hours before sunset: with August lows near 59°F, Augusta's siding meets the dew point before the late news.

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 can you paint outside?

50–90°F for standard formulas, 35°F+ for low-temp lines, and the wall itself must stay 5°F above the dew point. In Augusta the practical range is set by nights: the 40°F overnight floor arrives around May and leaves after October.

How many dry hours does exterior paint need before rain?

Plan 24 rain-free hours after the last coat; the engine fails any day that can't deliver them. With Augusta's rain odds swinging from 33% of days in February to 42% in May, the strip above is mostly a search for that dry pair.

Why does dew ruin fresh paint?

Fresh latex needs hours before it can take standing water; evening condensation gets there first on cooling siding. The check: air minus dew point from 6–11 p.m., 5°F or better. Humid May evenings in Augusta are when GOOD afternoons hide failing nights.

Can you paint in high humidity?

Up to about 80% daytime RH — above that, dry times stretch until the film meets the evening dew. 80–83% reads MARGINAL on the engine; more is a fail. Pair humidity with Augusta's dew-point spread rule and paint mornings-into-early-afternoons in the humid months.

What is surface temperature vs air temperature?

Two different numbers: air (what the app shows) and the wall (what the paint feels). Sun adds 20°F or more; evening radiational cooling subtracts. That's why the engine checks the 90°F top on Augusta's hot afternoons and the dew-point spread after sunset — both are surface problems the air forecast hides.

When does painting season end in Augusta?

The closing bell is the overnight floor. October is the last month averaging viable nights (40°F lows); after that, even warm afternoons sit on failing nights. Spring reopens around May from the same rule.

Other projects in Augusta

Exterior Painting nearby

Guides

Climatology: NOAA 1991–2020 normals via AUGUSTA STATE AP, ME US (5.5 km from Augusta center, elevation 350 ft); live outlook by Open-Meteo.