Oconomowoc Wwtp, WI Climate: Temperature & Rain by Month
Temperature and precipitation from NOAA NCEI 1991–2020 normals →, plus PlainClimate's derived comfort score
30-year climate normals (1991-2020) from Oconomowoc Wwtp's primary NOAA station, OCONOMOWOC WWTP.
The climate verdict for Oconomowoc Wwtp
Oconomowoc Wwtp, Wisconsin has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 47°F. Its climate comfort score of 59/100 (moderate) lands mid-pack nationally, exceeding 37% of station-mapped location scores.
- 47°F
- average temperature, NOAA 1991-2020 normal
- 59/100
- comfort score, above 37% of station-mapped location scores
- 36.8"
- annual precipitation · 40" snow
- 165 days
- frost-free days per growing season
Oconomowoc Wwtp: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00476200 · Oconomowoc Wwtp, WI 47°F mean · 36.8" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-MID · SWING-WIDE · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 47°F
- RANK-COOL #1,921
- PHOTO-FINISH ≈ UW Arboretum -…
- PRCP-MID 36.8"
- SWING-WIDE 52°F
- COMF-MID 59/100
- LOAD-HEAT 7,089 HDD
- STN-1 USC00476200
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: UW Arboretum - Madison, WI (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every WI station list.
- Oconomowoc Wwtp (this station) 47°F
- Hot Lone Rock Tri C…, WI 47°F
- Near UW Arboretum -…, WI 47°F
- Near Dubuque Rgnl, IA 47°F
- Near Dinosaur Nation…, CO 47°F
Climate Living Index · Oconomowoc Wwtp
Oconomowoc Wwtp: 46/100 · grade D
Oconomowoc Wwtp publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Oconomowoc Wwtp, not an official NOAA rating. Rankings still use Comfort Score 59/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 36.8 in · 1.8 from 35 in | 92/100 · A |
| Normal heat + freeze calendar | 151 calendar days | 46/100 · D |
| Frost-free season | 165 days/year | 38/100 · F |
| Annual temperature balance | 47.2°F · 20.3° from 67.5°F | 28/100 · F |
| Snowfall burden | 39.6 inches/year | 28/100 · F |
Oconomowoc Wwtp · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Oconomowoc Wwtp is a continental Köppen climate: Dfa
Coldest-month mean 19.6°F and warmest-month mean 71.8°F place this station in continental, no dry season, hot summer climates (Dfa). Class Dfa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, no dry season, hot summer.
- Köppen code
- Dfa
- Group
- Continental
- Warmest month
- 71.8°F
- Coldest month
- 19.6°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Oconomowoc Wwtp sits across the climate record
Three NOAA fields for Oconomowoc Wwtp's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 72%
- Among 6,861 stations, Oconomowoc Wwtp sits in the cooler third of annual means.
- Annual precipitation
- 51st percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 86%
- Warmest-to-coldest month gap for Oconomowoc Wwtp is large versus 6,861 complete station-years.
How Oconomowoc Wwtp compares across U.S. station-mapped locations
Oconomowoc Wwtp's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
59 37th percentile score exceeds 37% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). This entry sits in this band.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Oconomowoc Wwtp's measured station temperature trend
MethodologyAcross 69 complete annual observations from 1894 to 2025, OCONOMOWOC WWTP warmed at a fitted rate of 0.13°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Oconomowoc Wwtp primary station fitted change +0.13 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 28°F (-2°C) | 11°F (-12°C) | 20°F (-7°C) | 1.6" | 11.1" | 29.5 | 0.0 |
| February | 32°F (0°C) | 14°F (-10°C) | 23°F (-5°C) | 1.6" | 9.8" | 26.5 | 0.0 |
| March | 44°F (7°C) | 25°F (-4°C) | 34°F (1°C) | 2.1" | 4.8" | 23.9 | 0.0 |
| April | 56°F (14°C) | 36°F (2°C) | 46°F (8°C) | 3.9" | 2.0" | 9.9 | 0.0 |
| May | 69°F (20°C) | 47°F (8°C) | 58°F (14°C) | 4.1" | 0.2" | 1.0 | 0.2 |
| June | 78°F (26°C) | 57°F (14°C) | 68°F (20°C) | 4.9" | 0.0" | 0.0 | 1.7 |
| July | 82°F (28°C) | 61°F (16°C) | 72°F (22°C) | 4.1" | 0.0" | 0.0 | 3.2 |
| August | 81°F (27°C) | 60°F (15°C) | 70°F (21°C) | 4.2" | 0.0" | 0.0 | 1.5 |
| September | 74°F (23°C) | 52°F (11°C) | 63°F (17°C) | 3.4" | 0.0" | 0.2 | 0.8 |
| October | 61°F (16°C) | 40°F (4°C) | 50°F (10°C) | 2.8" | 0.1" | 7.0 | 0.0 |
| November | 46°F (8°C) | 29°F (-2°C) | 37°F (3°C) | 2.2" | 1.4" | 19.5 | 0.0 |
| December | 34°F (1°C) | 18°F (-8°C) | 26°F (-3°C) | 1.9" | 10.2" | 28.0 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 83°F around July 14, short of 90°F on every date, while 151 dates carry a normal low at or below freezing, the coldest 10°F near January 23.
The freezing stretch
The normal low stays at or below 32°F into April 5, then returns to freezing around November 7, covering 151 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is April 30, when 42% of years recorded at least a hundredth of an inch. The driest is August 31 at 31%. Summed across the calendar, that is about 129 wet dates a year.
The widest day
September 26 carries the biggest normal gap between afternoon and dawn, 23°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Oconomowoc Wwtp.
Where Oconomowoc Wwtp Stands Nationally
Days and nights track unusually close together; the widest normal swing, about 23°F, is narrower than most stations record.
Oconomowoc Wwtp earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 11.1"
11.0 days with precipitation
Snow: 9.8"
9.8 days with precipitation
Snow: 4.8"
9.9 days with precipitation
Snow: 2.0"
12.3 days with precipitation
Snow: 0.2"
13.2 days with precipitation
11.7 days with precipitation
10.4 days with precipitation
9.9 days with precipitation
9.5 days with precipitation
Snow: 0.1"
10.8 days with precipitation
Snow: 1.4"
9.7 days with precipitation
Snow: 10.2"
11.0 days with precipitation
Oconomowoc Wwtp runs a summer-peaked wet season
36% of Oconomowoc Wwtp's yearly precipitation falls in June, July and August alone, against the 25% an evenly spread year would give those three months. The wettest month is June at 4.9", on a wide 52.2°F gap between its warmest and coldest month. Warm-season convection and, across the Southwest, the North American monsoon produce this shape: rain arrives in short heavy bursts during the hottest part of the year rather than as long cool-season soaking.
- Wettest three months: June, August, May, taking 36% of the annual total between them.
- Driest month: February at 1.6".
- Winter share: 14% falls in December, January and February.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A summer-peaked label means the June-August share reaches 35%; it describes timing across an average year, not any single season, and says nothing about how heavy an individual storm can be.
How Oconomowoc Wwtp's precipitation splits across the calendar
About 129 days a year record measurable precipitation here, carrying 36.8" between them, or roughly 0.28 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Winter brings real snow to Oconomowoc Wwtp
Oconomowoc Wwtp averages 39.6 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 31 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 39.6 inches of depth.
- Days recording measurable snow: about 31 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 11% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 12
50% probability date
Last Spring Freeze
April 30
50% probability date
Growing Season
165 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,089
Higher = more heating needed
Cooling Degree Days
643
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside WI closest to Oconomowoc Wwtp on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (47°F here).
- Amboy, MN 47°F · 0.0°F off
- Burton, MI 47°F · 0.0°F off
- Concord, NH 47°F · 0.0°F off
- Harrington, WA 47°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (36.8" here), excluding temperature-peer places.
- Waverly, NY 36.8" · 0.0" off
- Preston, MN 36.8" · 0.0" off
- Troy, KS 36.8" · 0.0" off
- Walnut, IL 36.8" · 0.0" off
Snow and freeze rhythm
When cold and snow define Oconomowoc Wwtp
heating led · moderate · mid swing
Oconomowoc Wwtp's energy balance leans toward cold weather: 7,089 annual heating degree days against 643 for cooling. Its 52.2°F seasonal range still makes the monthly rows more useful than the annual average alone.
Oconomowoc Wwtp's frost-free season lasts about 165 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
-
1. Oconomowoc Wwtp coldest normal
January
Averaging 20°F (-7°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Oconomowoc Wwtp typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Oconomowoc Wwtp snow peak
January
Oconomowoc Wwtp averages 39.6 inches of snow a year, with January the snowiest month on the normals.
Questions about Oconomowoc Wwtp's climate
How much snow does Oconomowoc Wwtp get? ▼
How cold does Oconomowoc Wwtp get in winter? ▼
How much energy does heating and cooling require in Oconomowoc Wwtp? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Oconomowoc Wwtp's primary station: OCONOMOWOC WWTP (USC00476200). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Oconomowoc Wwtp; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Oconomowoc Wwtp comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.