Troy, Michigan climate: NOAA's gridded normals for the city, beside the nearest station records
NOAA's gridded 1991-2020 normals put Troy's center at January lows of 18°F and July highs of 83°F, a yearly mean of 49.2°F and 33.4 inches of precipitation. No NOAA station keeps a record under the city's name. The nearest station record, Pontiac Wastewater Treatment Plant (7 miles NW, 890 ft), has January lows of 17°F and July highs of 82°F.
89,209 people (Census Bureau 2024). Distances and directions are from the city's center.
- Jan 31° 18°
- Feb 34° 19°
- Mar 45° 27°
- Apr 58° 37°
- May 70° 48°
- Jun 79° 58°
- Jul 83° 62°
- Aug 81° 61°
- Sep 74° 53°
- Oct 61° 43°
- Nov 48° 32°
- Dec 36° 24°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
The months above are NOAA's gridded normals at Troy's center.
What is each month like in Troy?
NOAA's grid estimates the normals every 5 km or so from the stations around each point, terrain included. It smooths between stations, so night lows at the heart of a large city can run warmer than the grid shows: at five big-city airports we compared, the grid's highs were within about 1°F of the station and its lows 1-6°F cooler. The nearest record's high and low are beside each month.
| Month | High | Low | Mean | Precip. | Pontiac Wastewater Treatment Plant high | Pontiac Wastewater Treatment Plant low |
|---|---|---|---|---|---|---|
| January | 31°F | 18°F | 24.5°F | 2.14 | 31°F | 17°F |
| February | 34°F | 19°F | 26.5°F | 1.82 | 34°F | 18°F |
| March | 45°F | 27°F | 35.5°F | 2.22 | 44°F | 26°F |
| April | 58°F | 37°F | 47.3°F | 3.04 | 58°F | 36°F |
| May | 70°F | 48°F | 58.8°F | 3.84 | 69°F | 49°F |
| June | 79°F | 58°F | 68.6°F | 3.31 | 78°F | 59°F |
| July | 83°F | 62°F | 72.8°F | 3.38 | 82°F | 63°F |
| August | 81°F | 61°F | 71.0°F | 3.28 | 81°F | 62°F |
| September | 74°F | 53°F | 63.8°F | 3.10 | 74°F | 54°F |
| October | 61°F | 43°F | 51.8°F | 2.70 | 61°F | 42°F |
| November | 48°F | 32°F | 39.9°F | 2.48 | 47°F | 32°F |
| December | 36°F | 24°F | 30.2°F | 2.11 | 36°F | 24°F |
In metric: a yearly mean of 9.6°C, January lows of −8°C, July highs of 29°C and 849 mm of precipitation a year.
Source: NOAA NCEI U.S. Monthly Gridded Climate Normals 1991-2020 (nClimGrid, accession 0245564); NOAA NCEI 1991-2020 station normals. The grid cell holding the city's Census center point.
What do the station records around Troy say?
Each row is a NOAA station's own 1991-2020 normals, with the snow and frost dates the grid does not give. A record downhill or nearer the coast than the city can run warmer, one uphill cooler: compare the elevations.
| Record | Where | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Pontiac Wastewater Treatment Plant | 7 mi NW | 890 ft | 49.1°F | 17°F | 82°F | 33.9 | 36 | April 26 |
| Farmington | 14 mi SW | 720 ft | 47.6°F | 16°F | 83°F | 33.0 | 36 | May 1 |
| PontiacPontiac Oakland County International Airport | 15 mi W | 976 ft | 48.4°F | 17°F | 82°F | 29.2 | – | April 29 |
Source: NOAA NCEI 1991-2020 U.S. Climate Normals; place center and population: Census Bureau 2024. Last frost: the median last spring date of 32°F.
How much snow, how late a frost, what zone and how much sun in Troy?
NOAA's grid gives no snow, frost dates or records, so these come from the nearest station record, Pontiac Wastewater Treatment Plant (7 miles NW, 890 ft). It gets 36 inches of snow in a normal year. The last spring frost (32°F) comes after April 26 in half of years and the first autumn frost before October 22. Its record high is 104°F (1936) and its record low −22°F (1918) (kept since 1894).
The USDA's 2023 Plant Hardiness Zone Map puts Troy in zone 6b across its 4 ZIP code areas.
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area (3.8 kWh per square metre a day, NASA POWER 2001-2020); July is the sunniest month (80%) and December the cloudiest (54%).
Pontiac Wastewater Treatment Plant's page has its months, frost probabilities, records by month and recent years. NOAA's grid has monthly figures only, so there are no day-by-day month pages for Troy; the nearest record's month pages have them.
Source: NOAA NCEI 1991-2020 normals, station USC00206658; records: ACIS; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; sunshine: NASA POWER.
How does the climate vary across Troy, ZIP code by ZIP code?
4 ZIP code areas lie wholly or partly in Troy. On NOAA's grid 48083 is the warmest (49.6°F a year) and 48098 the coolest (49.0°F), a spread of 0.6°F. Each row also names the nearest station record and its frost dates.
| ZIP code | Zone | Year | Jan low | Jul high | Precip. | Nearest record | Last frost | First frost |
|---|---|---|---|---|---|---|---|---|
| 48083 | 6b | 49.6°F | 18°F | 84°F | 33.4 | Pontiac Wastewater Treatment Plant (9 mi) | April 26 | October 22 |
| 48084 | 6b | 49.2°F | 18°F | 83°F | 33.4 | Pontiac Wastewater Treatment Plant (7 mi) | April 26 | October 22 |
| 48085 | 6b | 49.4°F | 18°F | 84°F | 33.5 | Pontiac Wastewater Treatment Plant (7 mi) | April 26 | October 22 |
| 48098 | 6b | 49.0°F | 17°F | 83°F | 33.4 | Pontiac Wastewater Treatment Plant (5 mi) | April 26 | October 22 |
Source: Census Bureau 2020 ZCTA-to-place relationship file and ZCTA centers; NOAA NCEI gridded and station normals, 1991-2020. A ZIP area counts when at least a tenth of its land (and 0.5 km²) is in the city; its figures are the grid cell at its center; frost dates are the nearest record's medians of 32°F.