Katy weather in December

In December, Katy sees average daytime highs of 65°F and overnight lows near 46°F, with 3.9 in of rain across 9.3 wet days and about 10.1 hours of daylight. It is the 11th-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 67°F in the first days to 63°F by the end. The sky is clear or mostly clear about 32% of the time in December, and the air most often feels dry.

Daylight stretches from about 10 h 12 min at the start of December to 10 h 06 min by month's end. Set against the rest of the year, December is Katy's 11th-clearest and 5th-windiest month. For the whole year in context, see Katy's year-round climate.

Daytime high
65°
11th warmest
Overnight low
46°
2nd coldest
Rainfall
3.9 in
9.3 wet days
Daylight
10 h 06 min
7:17 AM – 5:22 PM
Cloud cover
59%
11th clearest
Wind
8 mph
5th windiest
Solar energy
2.61 kWh/m²
Travel score
6.0
out of 10

Katy is city in Harris, Waller, and Fort Bend counties in Texas, United States.

Density
552/km²
people per km²
Founded
1945

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 67°F in the first days to 63°F by the end.

A typical December day in Katy reaches about 65°F in the afternoon and slips back to 46°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 51°F and 77°F. Set against its neighbours, December runs about 7°F cooler than November and about 1°F warmer than January.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
16849
26748
36748
46748
56748
66648
76647
86647
96647
106547
116547
126547
136547
146546
156546
166546
176446
186446
196446
206446
216446
226446
236445
246345
256345
266345
276345
286345
296345
306345
316245

How December really feels in Katy

Once humidity and wind are folded in, December averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

December sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Katy weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan63° / 45°3.79.510.35.7
Feb67° / 48°2.98.610.96.2
Mar73° / 54°3.2911.86.9
Apr79° / 60°3.68.412.76.9
May86° / 68°3.69.713.55.1
Jun91° / 74°4.212.313.93.6
Jul93° / 76°3.111.613.73.0
Aug93° / 75°3.311.513.12.9
Sep89° / 71°3.911.412.24.2
Oct81° / 62°3.9911.36.6
Nov72° / 53°3.78.410.57.0
Dec65° / 46°3.99.310.16.0

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 32% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 13% of December, with mostly cloudy or overcast conditions the remaining 54%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15050
24951
34753
44753
54753
64654
74654
84654
94654
104555
114456
124654
134654
144654
154654
164753
174753
184753
194654
204654
214654
224654
234654
244654
254654
264456
274456
284357
294357
304258
314258

Chance of precipitation in December

Any precipitation

Katy gets around 3.9 in of rain over 9.3 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 30% and peaks near 31% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
130
230
330
430
530
629
729
829
929
1030
1130
1230
1330
1431
1531
1631
1731
1831
1931
2031
2131
2231
2331
2431
2531
2630
2730
2830
2929
3029
3129

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

Most of December feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, December lands in the dry band about 71% of days. Sticky, muggy-or-worse air turns up on roughly 8% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1651112111
2651112111
3661111111
4661111111
5671111101
6671111101
7671111101
868111191
968111191
1068111191
1168121181
1268121181
1370121071
1470121071
1570121071
1670121071
1771121061
1872111061
1972111061
2072111061
2172111061
2273101061
2373101061
2473101061
257491061
267491061
27769960
28779950
29779950
30779950
31779950

Wind in December

Winds average 8 mph in December.

Across December, daily wind ranges from about 8 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
48light breeze
58light breeze
68light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
128light breeze
138light breeze
148light breeze
158light breeze
168light breeze
178light breeze
188light breeze
198light breeze
208light breeze
218light breeze
228light breeze
238light breeze
248light breeze
258light breeze
268light breeze
278light breeze
288light breeze
298light breeze
308light breeze
318light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 10 h 12 min at the start of December to 10 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over December. Sunrise moves from 7:06 AM to 7:23 AM, and sunset from 5:20 PM to 5:30 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.27:065:20
210.27:075:20
310.27:085:20
410.27:095:20
510.27:095:20
610.27:105:20
710.27:115:20
810.17:115:20
910.17:125:20
1010.17:135:21
1110.17:135:21
1210.17:145:21
1310.17:155:21
1410.17:155:22
1510.17:165:22
1610.17:175:22
1710.17:175:23
1810.17:185:23
1910.17:185:23
2010.17:195:24
2110.17:195:24
2210.17:205:25
2310.17:205:25
2410.17:215:26
2510.17:215:26
2610.17:215:27
2710.17:225:27
2810.17:225:28
2910.17:235:29
3010.17:235:29
3110.17:235:30

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.61 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.61 kWh/m² to a high of 6.28 kWh/m² in July across the year — December's 2.61 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.8Moderate
22.7Moderate
32.7Moderate
42.7Moderate
52.7Moderate
62.7Moderate
72.6Moderate
82.6Moderate
92.6Moderate
102.6Moderate
112.6Moderate
122.6Moderate
132.6Moderate
142.6Moderate
152.6Moderate
162.6Moderate
172.6Moderate
182.6Moderate
192.6Moderate
202.6Moderate
212.6Moderate
222.6Moderate
232.6Moderate
242.6Moderate
252.6Moderate
262.6Moderate
272.6Moderate
282.6Moderate
292.6Moderate
302.6Moderate
312.6Moderate
Planning a trip in December

Is December a good time to visit Katy?

Our two travel scores rate December for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.0
Sightseeing
6th-best month of the year
2.2
Beach & pool
11th-best month of the year

December is a reasonable time to visit Katy for sightseeing.

What to pack for Katy in December

From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In December, Katy sees daytime highs around 65°F and nights near 46°F. Worth packing: a warm layer and rain gear. About 9 days see rain.

a warm layerrain gear

UV index in Katy in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Katy peaks around August 10 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 4 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateAug 10UV 11Dec 21UV 4
UV index (midday)Level
Jan4Moderate
Feb6High
Mar6High
Apr10Very high
May10Extreme
Jun10Extreme
Jul11Extreme
Aug11Extreme
Sep8Very high
Oct6High
Nov5Moderate
Dec4Moderate

Air quality in Katy in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Katy is worst in July — around 21 µg/m³ PM2.5 (moderate), about 2.7× the cleanest month (December, 8 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1520 µg/m³Dec 138 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb9Good
Mar11Good
Apr11Good
May15Moderate
Jun17Moderate
Jul21Moderate
Aug15Moderate
Sep12Moderate
Oct8Good
Nov8Good
Dec8Good
Location & terrain

Where is Katy?

Katy sits at 29.8°N, 95.8°W, 138 ft above sea level, in United States. The nearest listed city is Cinco Ranch, 5.0 mi away.

Topography around Katy

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Katy.

Within 2 miles, the terrain around Katy has only modest variations in elevation — a maximum elevation change of 72 ft around an average of 144 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 171 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 492 ft.

The land around Katy is covered by artificial surfaces (35%), trees (31%) and grassland (24%) within 2 miles, grassland (39%) and trees (30%) within 10 miles, and trees (41%) and grassland (37%) within 50 miles.

2 miles
72 ft
10 miles
171 ft
50 miles
492 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Cinco Ranch 5.0 mi · Mission Bend 11 mi · Pecan Grove 12 mi · Alief 15 mi · Cypress 15 mi · New Territory 16 mi · Rosenberg 16 mi · Sugar Land 16 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Katy (29.7858°, -95.8244°, elevation 138 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).