Tombee Plantation · Photo: Gwringle · CC BY-SA 3.0Port Royal has milder winter nights than 90% of U.S. towns
In July the day’s top temperature is typically 91°. August is the wettest month, November the driest. Summer afternoons here are warmer than in 80% of U.S. towns. Seedlings are safe outdoors from about March 3, with the first autumn frost due around December 9.
A year in Port Royal at a glance
Each month’s typical high and low, and what it brings.
What stands out about Port Royal’s climate
Compared with towns across the U.S., with Port Royal’s place in South Carolina beside it.
What a year in Port Royal feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 282 frost-free days a year
In half of years the last 32° night comes by March 3 and the first by December 9. Frost and day counts come from NOAA’s station at Beaufort Wwtp, SC, 2.9 miles from the town’s center, at about the same height.
The 2023 USDA map puts Port Royal’s center in zone 9a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 25°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 49 inches of rain a year
August is the wettest month and November the driest. Rain falls on about 118 days a year. Snow is rare: about 0.0" in a normal year at Beaufort Mcas, SC, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Port Royal
38% of the work is heating, so air conditioning is the bigger bill. Months averaging under 55° run from December through February.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Beaufort Wwtp, SC.
Living with Port Royal’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
282 frost-free days in zone 9a. The last frost comes by Mar 3 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Dec 9.
Months with highs of 62–84° and lows of 40° or more: February, March, April, May, October, November and December. 9.5 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Port Royal from natural hazards, hurricanes are the largest share (80%); heat waves, cold waves, winter storms and ice storms together are 3%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Port Royal and its neighbors
Every town next door is within a degree of Port Royal in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Port Royal’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Port Royal, SC | 41° | 91° | 49" | 0.0" |
| Tifton, GA | 38° | 91° | 49" | 0.0" |
| Macclenny, FL | 41° | 92° | 52" | 0.0" |
| Clute, TX | 46° | 91° | 50" | 0.0" |
| Phenix City, AL | 36° | 92° | 51" | 0.0" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Port Royal averaged 1.0° warmer than the 1900s. The biggest change is in December (+1.8°).
A smaller shift than in 80% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Port Royal compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Port Royal’s place among South Carolina’s.
Port Royal weather by month
Highs, lows and precipitation from NOAA’s grid at Port Royal’s center; snow, wet days and snow on the ground from Beaufort Mcas, SC. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 60° | 41° | 3.4" | 0.0" | 9 | 0 | 45° – 57° |
| February | 63° | 43° | 3.2" | 0.0" | 9 | 0 | 46° – 63° |
| March | 69° | 49° | 3.4" | 0.0" | 9 | 0 | 53° – 66° |
| April | 76° | 56° | 3.2" | 0.0" | 9 | 0 | 61° – 71° |
| May | 83° | 65° | 3.2" | 0.0" | 8 | 0 | 70° – 79° |
| June | 88° | 72° | 5.3" | 0.0" | 13 | 0 | 75° – 84° |
| July | 91° | 75° | 5.8" | 0.0" | 13 | 0 | 80° – 86° |
| August | 89° | 74° | 6.6" | 0.0" | 13 | 0 | 79° – 84° |
| September | 85° | 70° | 4.7" | 0.0" | 10 | 0 | 75° – 82° |
| October | 78° | 60° | 4.2" | 0.0" | 8 | 0 | 65° – 74° |
| November | 69° | 50° | 2.6" | 0.0" | 8 | 0 | 55° – 65° |
| December | 62° | 43° | 3.1" | 0.0" | 10 | 0 | 44° – 64° |
| Year | 76° | 58° | 48.5" | 0.0" | 118 | 0 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 44° to 64°. August is the most reliable, staying within 5°.
Where Port Royal’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Port Royal’s center.
- Snow: Beaufort Mcas, SC.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Beaufort Wwtp, SC, 2.9 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Port Royal’s climate
What is the weather like in Port Royal?
A typical July afternoon reaches 91°, a January night drops to 41°, and snow is almost unheard of. Milder January nights than 90% of U.S. towns; hotter July afternoons than 80% of U.S. towns.
How cold does it get in Port Royal in winter?
January nights average 41°. About 13 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 45°.
How much snow does Port Royal get?
About 0.0 inches in a normal winter at Beaufort Mcas, SC, so most winters see none.
How hot does it get in Port Royal?
July, with a typical high of 91° and a low of 75°. About 58 days a year reach 90° and 1 reach 100° (Beaufort Wwtp, SC).
When is the first and last frost in Port Royal?
In half of years the last spring frost (32°) comes by March 3 and the first fall frost by December 9, about 282 frost-free days, at Beaufort Wwtp, SC.
What growing zone is Port Royal in?
Zone 9a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 25°.
What is the best time of year to visit Port Royal?
By one simple rule (highs of 62–84° and lows of 40° or more), February, March, April, May, October, November and December. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Port Royal getting warmer?
Yes: 1991–2020 averaged 1.0° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 80% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Port Royal.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.