Merced, California climate: Normal weather by month, frost dates and records
Merced's normal year runs from 36°F December nights to 96°F July afternoons, with 11.8 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 16.8°C, December lows of 2°C, July highs of 36°C, 300 mm of precipitation a year.
- NOAA stationMerced Municipal Airport
- Station IDUSW00023257
- Location37.28°N 120.51°W
- Elevation152 ft (46 m)
- Population96,073
On October 22, the normal high in Merced is 77°F and the normal low 47°F, and the chance of measurable rain or snow is 12%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Merced.
- Jan 56° 37°
- Feb 62° 39°
- Mar 68° 42°
- Apr 74° 45°
- May 83° 52°
- Jun 91° 58°
- Jul 96° 62°
- Aug 95° 61°
- Sep 91° 57°
- Oct 80° 49°
- Nov 66° 41°
- Dec 56° 36°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Merced each month?
July is the warmest month, with normal highs of 96°F; December the coldest, with normal lows of 36°F. The most precipitation falls in January (2.37 in), the least in July (0.00 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 56°F | 37°F | 46.3°F | 2.37 | 10 | <1 | 8 | 9 h 50 min |
| February | 62°F | 39°F | 50.5°F | 2.20 | 10 | <1 | 4 | 10 h 50 min |
| March | 68°F | 42°F | 55.2°F | 1.82 | 8 | <1 | 1 | 11 h 50 min |
| April | 74°F | 45°F | 59.7°F | 1.12 | 5 | 1 | <1 | 13 h 10 min |
| May | 83°F | 52°F | 67.4°F | 0.55 | 3 | 7 | <1 | 14 h 10 min |
| June | 91°F | 58°F | 74.2°F | 0.12 | 1 | 19 | <1 | 14 h 40 min |
| July | 96°F | 62°F | 79.0°F | 0.00 | <1 | 27 | <1 | 14 h 30 min |
| August | 95°F | 61°F | 77.9°F | 0.00 | <1 | 26 | <1 | 13 h 40 min |
| September | 91°F | 57°F | 73.5°F | 0.05 | 1 | 17 | <1 | 12 h 30 min |
| October | 80°F | 49°F | 64.3°F | 0.64 | 3 | 3 | <1 | 11 h 20 min |
| November | 66°F | 41°F | 53.5°F | 1.02 | 7 | <1 | 3 | 10 h 10 min |
| December | 56°F | 36°F | 46.0°F | 1.91 | 10 | <1 | 11 | 9 h 40 min |
| Year (annual) | 76°F | 48°F | 62.3°F | 11.80 | 56 | 100 | 28 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 13°C | 3°C | 7.9°C | 60 mm |
| February | 17°C | 4°C | 10.3°C | 56 mm |
| March | 20°C | 6°C | 12.9°C | 46 mm |
| April | 23°C | 7°C | 15.4°C | 28 mm |
| May | 28°C | 11°C | 19.7°C | 14 mm |
| June | 33°C | 14°C | 23.4°C | 3 mm |
| July | 36°C | 17°C | 26.1°C | 0 mm |
| August | 35°C | 16°C | 25.5°C | 0 mm |
| September | 33°C | 14°C | 23.1°C | 1 mm |
| October | 26°C | 9°C | 17.9°C | 16 mm |
| November | 19°C | 5°C | 11.9°C | 26 mm |
| December | 13°C | 2°C | 7.8°C | 49 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Merced's own co-op station Merced station does: 0 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USW00023257; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Merced?
Normal highs sit between 65°F and 85°F in March, April, May, October and November. Of those, May has the fewest days with rain (3).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00023257.
When is the last frost in Merced?
In Merced, the last spring frost (32°F) comes after February 26 in half of years and after April 1 in one year in ten; the first autumn frost comes before November 25 in half of years and before November 9 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- February 261 year in 10 after April 1; 9 in 10 after January 20
- First autumn frost, half of years before
- November 251 year in 10 before November 9; 9 in 10 before December 16
NOAA puts the median frost-free season at 273 days, and the season without a hard freeze (28°F) at 329 days.
A hard freeze (28°F) comes after January 22 in half of springs and before December 10 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Merced in zones 9a to 9b across its 2 ZIP code areas (9a in 95340, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Merced's NOAA station is in zone 9a: the coldest night of a typical year reaches 25°F (22 complete years).
Frost dates for every NOAA station in California · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00023257; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Merced ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Merced's 2 ZIP code areas run from zone 9a to 9b: 1 in 9a and 1 in 9b. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Merced?
In a normal year in Merced, 100 days a year reach 90°F (23 of them 100°F or more), 28 nights fall to 32°F or colder and 56 days bring measurable precipitation.
- Days at 90°F or more
- 100a normal year
- Days at 100°F or more
- 23a normal year
- Nights at 32°F or colder
- 28a normal year
- Days that stay below freezing
- fewer than 1high of 32°F or less
- Days with 0.01 inch of precipitation
- 56a normal year
The highest temperature in Merced's official record (kept by the National Weather Service since 1899) is 116°F, on September 6, 2022; the lowest is 15°F, on December 24, 1990.
The wettest calendar year on that record is 1996, with 18.42 in.
Source: NOAA NCEI 1991-2020 annual normals, station USW00023257; records: ACIS (NOAA Regional Climate Centers), NWS threaded record MCEthr. Records use complete months only; a month missing more than three days is left out.
How sunny is Merced?
Over a year 90% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Merced, 5.3 kWh per square metre a day. July is the sunniest month (98%) and January the cloudiest (71%). Among the 459 U.S. places of 50,000 or more, that ranks tied 21st (with 17 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 71% | 2.3 |
| February | 78% | 3.5 |
| March | 82% | 4.9 |
| April | 86% | 6.3 |
| May | 92% | 7.6 |
| June | 96% | 8.4 |
| July | 98% | 8.2 |
| August | 98% | 7.4 |
| September | 96% | 6.0 |
| October | 92% | 4.4 |
| November | 82% | 2.9 |
| December | 72% | 2.1 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Merced need?
A normal year in Merced brings 2,551 heating degree days, 53% fewer than the median U.S. place (5,373), and 1,583 cooling degree days, 74% more than the median (908). Five months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 4,882 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 580 | 0 |
| February | 405 | 0 |
| March | 305 | 1 |
| April | 181 | 22 |
| May | 48 | 122 |
| June | 5 | 279 |
| July | 0 | 434 |
| August | 0 | 399 |
| September | 7 | 262 |
| October | 85 | 64 |
| November | 348 | 1 |
| December | 589 | 0 |
| Year (annual) | 2,551 | 1,583 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00023257. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Merced been warmer than normal lately?
2025 averaged 63.2°F, 0.9°F above the 1991-2020 normal of 62.3°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 63.7°F | +1.4°F | 10.51 |
| 2022 | 64.0°F | +1.7°F | 8.06 |
| 2023 | 62.7°F | +0.4°F | 17.75 |
| 2024 | 65.3°F | +3.0°F | 15.11 |
| 2025 | 63.2°F | +0.9°F | 11.88 |
Over 92 complete years from 1875 to 2025, the station's annual mean temperature rose at a fitted 0.9°F per century (+0.05°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00023257; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Merced's climate compare?
Merced is warmer than 127 of the other 218 places with their own NOAA record in California, and wetter than 58. Across the 7,247 U.S. stations with normals, its annual mean of 62.3°F is warmer than 81%.
In the Köppen classification computed from these normals, Merced is BSk: cold semi-arid steppe. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Merced share this climate record?
13 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Atwater, CA32,248 people · 7 mi NW
- Winton, CA11,429 people · 9 mi NW
- Franklin, CA7,487 people · 3 mi N
- McSwain, CA5,556 people · 5 mi NW
- Planada, CA3,524 people · 11 mi E
- Le Grand, CA1,773 people · 15 mi E
- University of California-Merced, CA886 people · 8 mi NE
- Catheys Valley, CA772 people · 25 mi NE
- El Nido, CA564 people · 11 mi S
- Snelling, CA265 people · 17 mi N
- Bear Creek, CA231 people · 5 mi E
- Tuttle, CA69 people · 7 mi E
- Hornitos, CA0 people · 21 mi NE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Merced's other NOAA stations record?
2 more NOAA stations keep 1991-2020 normals in or near Merced. This page uses Merced Municipal Airport; the others differ by site and elevation:
| Station | From this station | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Merced (23 mi WSW) USW00093243 | 21 mi W | 78 ft | 59.7°F | 36°F | 96°F | 10.4 | – | March 28 |
| Merced station USC00045532 | in town | 154 ft | 61.6°F | 37°F | 95°F | 12.5 | 0 | March 3 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Merced's climate
What is the coldest month in Merced?
December, with a normal high of 56°F and a normal low of 36°F. The warmest is July (96°F by day, 62°F at night).
Does it snow in Merced?
Rarely. NOAA publishes no 1991-2020 snowfall normal for Merced's NOAA station; Merced's own co-op station Merced station records 0 inches of snow in a normal year.
What is the rainiest month in Merced?
January, with 2.37 in of precipitation in a normal year; the driest is July with 0.00 in.
What plant hardiness zone is Merced in?
The USDA's 2023 map puts Merced in zones 9a to 9b across its 2 ZIP code areas (9a in 95340, the largest). By the same method at Merced's NOAA station, the coldest night of a typical year reaches 25°F (22 years, 1991-2020): zone 9a.
How late can frost come in Merced?
In half of years the last 32°F night comes after February 26; in one year in ten it comes after April 1. Waiting until April 1 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Merced in OctoberThis month day by day, its records and recent years
- California climateThe statewide normals and every place in the state
- Turlock, CA24 miles from this station, 64.0°F a year
- Los Banos, CA25 miles from this station, 63.4°F a year
- Newman, CA28 miles from this station, 65.0°F a year
- Madera, CA30 miles from this station, 63.3°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made