Home / Prosper / 21 September 2017
Prosper
United States · 21 September 2017
← 20 September 201722 September 2017 →
Average
29.4°C
low 25.3° · high 34.7°
Rainfall
0.1mm
dry day
Wind
5.3m/s
daily average
Humidity
66.5%
daily average
Cloud
61%
cover
Pressure
1012hPa
daily average
The temperature ranged from 25.3°C around 08:00 to 34.7°C around 16:00. Rain was recorded for one hour, around 18:00 (0.1mm total).
How unusual was this day?
Compared against the same 135 calendar days (±7 days) across the other 9 years on file.
High temperature
86th percentile
Low temperature
100th percentile
Rainfall
60th percentile
Wind
96th percentile
A percentile of 100 means this was the hottest/wettest/windiest of the comparable days on file; 50 is right in the middle. This window's average temperature was 25.9°C, versus 29.4°C on this specific day.
Sun & daylight
Sunrise
07:14
Sunset
19:24
Day length
12h 10m
Hour by hour
Temperature (line) and hourly rainfall (bars), local time — America/Chicago.
Cumulative rainfall through the day.
| Local time | UTC | Temp °C | Feels °C | Rain mm | Wind m/s | Dir | Humidity % | Pressure hPa |
|---|---|---|---|---|---|---|---|---|
| 00:00 | 05:00 | 29.1 | 30.2 | 0 | 6.1 | SSE | 71 | 1012 |
| 01:00 | 06:00 | 28.2 | 29.7 | 0 | 5.7 | SSE | 75 | 1011 |
| 02:00 | 07:00 | 27.5 | 29 | 0 | 5.4 | SSE | 77 | 1012 |
| 03:00 | 08:00 | 27 | 28.6 | 0 | 5.6 | S | 81 | 1012 |
| 04:00 | 09:00 | 26.5 | 28.2 | 0 | 5.5 | S | 84 | 1012 |
| 05:00 | 10:00 | 25.6 | 27.8 | 0 | 4.9 | S | 90 | 1013 |
| 06:00 | 11:00 | 25.5 | 28.2 | 0 | 4.1 | S | 89 | 1013 |
| 07:00 | 12:00 | 25.5 | 28.1 | 0 | 4 | SSE | 88 | 1013 |
| 08:00 | 13:00 | 25.3 | 27.2 | 0 | 4.8 | SSE | 88 | 1014 |
| 09:00 | 14:00 | 26.3 | 27.4 | 0 | 5.9 | S | 83 | 1014 |
| 10:00 | 15:00 | 27.5 | 27.2 | 0 | 6.5 | S | 67 | 1014 |
| 11:00 | 16:00 | 28.7 | 28.8 | 0 | 6 | S | 64 | 1014 |
| 12:00 | 17:00 | 31.1 | 31.5 | 0 | 5.4 | S | 55 | 1014 |
| 13:00 | 18:00 | 32.2 | 33.1 | 0 | 4.9 | S | 53 | 1013 |
| 14:00 | 19:00 | 33.2 | 34.6 | 0 | 4.6 | S | 51 | 1012 |
| 15:00 | 20:00 | 34.1 | 35.2 | 0.01 | 4.6 | SSE | 48 | 1012 |
| 16:00 | 21:00 | 34.7 | 35.2 | 0 | 4.9 | SSE | 43 | 1011 |
| 17:00 | 22:00 | 34.7 | 35.3 | 0 | 5.5 | SSE | 47 | 1010 |
| 18:00 | 23:00 | 34 | 34.5 | 0.11 | 4.9 | SE | 45 | 1010 |
| 19:00 | 00:00 | 33.2 | 33.8 | 0 | 4.3 | SE | 45 | 1010 |
| 20:00 | 01:00 | 31.7 | 31.2 | 0 | 5.5 | SE | 48 | 1010 |
| 21:00 | 02:00 | 29.6 | 29 | 0 | 6.4 | SE | 57 | 1012 |
| 22:00 | 03:00 | 27.8 | 28.5 | 0 | 5.9 | SSE | 72 | 1013 |
| 23:00 | 04:00 | 26.8 | 27.6 | 0 | 5.7 | SSE | 75 | 1013 |
Nearby cities
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Data source & coverage — ERA5 reanalysis, 2016–2025 (10 years)details
- Source
- ERA5 reanalysis, accessed via the Copernicus Climate Change Service (C3S) Climate Data Store
- Data type
- Reanalysis — a physically consistent reconstruction combining a forecast model with historical observations, not a live station reading or a forecast
- Coverage
- 2016–2025 (10 years) for United States
- Location
- Prosper — 33.250°, -96.750°, ERA5 grid cell center, 5.0 km from requested point
- Time zone
- America/Chicago
- What's shown here
- The hourly and daily record for 21 September 2017 specifically — not a monthly average. See the Prosper climate overview for typical conditions.
- Spatial resolution
- 0.25° (~25 km) distributed grid — ERA5's native model resolution is finer; this is the publicly distributed regridded product
- Version / refreshed
- Methodology v2026.07 · data last refreshed December 31, 2025
- Limitations
- A model reconstruction, not a station observation — hyper-local extremes (a single storm cell, an urban heat pocket) can differ from a nearby gauge. See the full methodology.
- Attribution
- Generated using Copernicus Climate Change Service information
Cite this data
PastClimate (2026-07-17). Historical climate data for Prosper, United States (33.25°N, 96.75°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
PastClimate. (2026). Historical climate data for Prosper, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 17, 2026, from https://www.pastclimate.com/
"Historical Climate Data for Prosper, United States." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 17, 2026, www.pastclimate.com.
@misc{pastclimate,
author = {PastClimate},
title = {Historical climate data for Prosper, United States},
year = {2026},
note = {Derived from ERA5 (Hersbach et al., 2023), Copernicus Climate Change Service. Accessed 2026-07-17},
url = {https://www.pastclimate.com/}
}Notice something wrong with this data? Report a data issue.