Waterloo, IA

Iowa · Records since 1895–2026

☀️ 88°F Feels like 97°
Currently in Waterloo
As of 7:00 PM CDT

Records for July 28

🔥 Record High

103°F

July 28, 1916

+18° from 85° normal

❄ Record Low

45°F

July 28, 1925

-19° from 64° normal
🌞 Normal high: 85°F 🌑 Normal low: 64°F 1991–2020 normals

All-Time Records — Waterloo

🔥
112°F
Hottest Day Ever
Jul 14, 1936
-34°F
Coldest Day Ever
Jan 16, 2009
🌧
6.00"
Wettest Day Ever
Sep 8, 1941
14.0"
Most Snow in One Day
Nov 30, 1934

Top 10 Record Highs — July 28

# Temp Date
🏆 103°F July 28, 1916
2 102°F July 28, 1917
3 99°F July 28, 1955
4 98°F July 28, 2023
5 97°F July 28, 1931
6 96°F July 28, 1988
7 95°F July 28, 1964
8 95°F July 28, 1952
9 95°F July 28, 1941
10 95°F July 28, 1936

Top 5 Record Lows — July 28

# Temp Date
🥶 45°F July 28, 1925
2 49°F July 28, 1965
3 49°F July 28, 1928
4 50°F July 28, 2013
5 50°F July 28, 2005
About this data — Records are sourced from the NOAA Threadex dataset via RCC ACIS, a quality-controlled record for long-term climate stations. Threadex adjusts for station relocations and observation-time changes, making records comparable across all years since 1895–2026. Climate normals represent the 1991–2020 average.
1
day
Hot Streak
1 consecutive day at or above 92°F · since July 26
2 more days to heat wave status

Heat Wave Summary — Waterloo

threshold: 92°F (90th percentile of historical Jun–Aug highs)
4.5
Avg heat wave length
days (historical)
98°
Avg peak temp
during heat waves
6
Dangerous nights 2026
Overnights ≥ 70°F
0
Heat waves 2026
so far

2026 Daily High Temperature vs Normal

Year to date
Above normal Below normal

108 of 207 days with data were above the 1991–2020 normal high for their date.


Days ≥ 90°F Per Year

1895–2026
8
2026 so far
21
Avg/year 1970–2025
22
Avg/year (last 10 complete)
60
Most in a year (1936)

Average Daily High by Decade

Full year · complete decades only


Longest Heat Waves — Waterloo

# Dates Days Peak Avg High Avg Overnight Low
🏆 Jul 9, 1901 – Jul 27, 1901 19 107°F (Jul 24) 100°F 70°F
2 Jul 3, 1936 – Jul 18, 1936 16 112°F (Jul 13) 104°F 71°F
3 Jun 22, 1934 – Jul 2, 1934 11 107°F (Jun 27) 100°F 69°F
4 Jul 21, 1916 – Jul 31, 1916 11 104°F (Jul 29) 99°F 68°F
5 Jun 22, 1931 – Jul 1, 1931 10 106°F (Jun 28) 103°F 74°F
6 Jul 26, 1955 – Aug 4, 1955 10 103°F (Jul 30) 98°F 74°F
7 May 28, 1934 – Jun 5, 1934 9 108°F (May 31) 100°F 66°F
8 Jul 27, 1988 – Aug 4, 1988 9 105°F (Jul 31) 98°F 68°F
9 Jul 23, 1919 – Jul 31, 1919 9 101°F (Jul 27) 96°F 68°F
10 Jul 14, 1931 – Jul 22, 1931 9 99°F (Jul 17) 97°F 67°F

Heat Waves Per Year


Warm Summer Nights (Jun–Aug)

Nights where the overnight low exceeded the 1991–2020 normal low

28
2026 so far
above-normal nights
36.3
Avg / summer
1970–2020
56
Most in a summer
1943

Above-Normal Summer Nights Per Year

Average June–August Low by Decade

Overnight lows · complete decades only

Precipitation

Actual vs. 1991–2020 full-month and full-season normals

24.31"
2026 YTD
Normal: 22.29"
+2.02"
5.24"
July so far
July normal: 4.34"
+0.90"
11.15"
Summer so far
Summer normal: 14.23"
-3.08"
9
2026 heavy rain days
Days with ≥ 1.0"

Monthly Precipitation — Last 24 Months

Blue = actual · dashed line = monthly normal

Annual Precipitation Per Year (1970–2026)

Blue = above average · tan = below average · gold = 2026 (partial)

Heavy Rain Days Per Year (≥ 1.0")

Compare year-to-year changes in days with heavy rainfall (≥ 1.0")