Dallas is 0.5°C (0.9°F) warmer by day, Dallas has 1.4°C (2.5°F) warmer nights, Dallas gets 600 mm (23.6 in) more rain a year.
Dallas is at its warmest in August and coolest in January, while San Diego peaks in August and bottoms out in January. Month for month, Dallas is the warmer of the two in 7 of 11 months.
Dallas is the wetter of the two, collecting 957 mm (37.7 in) of rain a year against 357 mm (14.1 in) in San Diego. The most comfortable time to visit is April, May and October in Dallas and June, September and October in San Diego.
| Dallas | Metric | San Diego |
|---|---|---|
| 🌡️ Temperature | ||
| 76.5°F | 🌡️Average daytime high | 75.6°F |
| 54.9°F | 🌙Average nighttime low | 52.3°F |
| August | 🔥Hottest month | August |
| January | ❄️Coldest month | January |
| 🌧️ Rain | ||
| 37.7 in | 🌧️Annual rainfall | 14.1 in |
| May | ☔Wettest month | February |
| January | 🏜️Driest month | June |
| 💨 Climate | ||
| 69% | 💧Average humidity | 57% |
| 3.1 m/s | 💨Average wind speed | 2.3 m/s |
Overnight, Dallas typically falls to around 12.7°C (54.9°F) while San Diego settles near 11.3°C (52.3°F).
Dallas is hottest in August and coldest in January, whereas San Diego peaks in August and is coolest in January.
Dallas sees the most rain in May and the least in January; San Diego is wettest in February and driest in June.
Dallas feels the more humid of the two, averaging 69% relative humidity against 57%.
For San Diego, the pick of the year is June, September and October.
Month by month, here is the coldest night, the average day and the hottest afternoon each city can expect. Switch Compare to read rainfall, humidity, wind or solar instead, and Period to move between the long-term 45-year average and any single year — the shading is a quick warm-to-cool guide.
| Month | Dallas | San Diego | ||||
|---|---|---|---|---|---|---|
| Min | Avg | Max | Min | Avg | Max | |
| January | 33.3 | 43.9❄️ | 54.3 | 43.3 | 52.9❄️ | 62.4 |
| February | 37.2 | 48 | 59 | 44.1 | 53.8 | 63.7 |
| March | 45.1 | 56.5 | 67.8 | 45.7 | 56.3 | 66.9 |
| April | 52.9 | 64.4 | 75.7 | 48 | 59.7 | 71.4 |
| May | 62.6 | 72.9 | 83.1 | 51.4 | 64 | 76.5 |
| June | 71.1 | 81 | 90.9 | 56.3 | 70.2 | 84 |
| July | 75 | 86 | 96.8 | 62.8 | 76.6 | 90.5 |
| August | 75.7 | 86.7🔥 | 97.7 | 64.8 | 78.3🔥 | 91.9 |
| September | 67.8 | 79 | 90.1 | 62.4 | 75.2 | 88 |
| October | 56.1 | 67.8 | 79.3 | 56.1 | 67.8 | 79.7 |
| November | 44.6 | 55.4 | 66.2 | 48.9 | 59.5 | 70 |
| December | 36 | 46.2 | 56.5 | 43.5 | 53.1 | 62.4 |
| Annual Avg | 54.9 | 65.7 | 76.5 | 52.3 | 64 | 75.6 |
Min / mean / max temperature (°F). 🔥 marks each city's hottest month, ❄️ its coldest; shading runs cool blue to warm red.
The same figures plotted out, so the shape of a typical year is easier to see than in a grid. Where the two lines run close together Dallas and San Diego feel alike; where they separate, they are genuinely different places to be.
Hover or tap any point to read the exact figures. Dallas San Diego
See how Dallas and San Diego stack up against other cities. Swipe for more.
Choose which city to keep, then search for any other city in our database — we'll build the comparison for you.
Quick answers to the questions people ask most when comparing Dallas and San Diego — each drawn straight from the climate figures above.
Dallas is the warmer of the two. It averages daytime highs of 24.7°C (76.5°F) against 24.2°C (75.6°F) in San Diego — roughly 0.5°C (0.9°F) warmer by day. Nights are milder in Dallas, with average lows of 12.7°C (54.9°F) versus 11.3°C (52.3°F).
Dallas is hottest in August, averaging highs of about 36.5°C (97.7°F), while San Diego peaks in August at around 33.3°C (91.9°F). That makes Dallas the hotter of the two at the height of summer.
Dallas gets colder. In its coldest month (January) overnight lows average about 0.7°C (33.3°F), compared with 6.3°C (43.4°F) at the low point of the year in San Diego.
Dallas is the wetter city, collecting about 957 mm (37.7 in) of rain a year versus 357 mm (14.1 in) in San Diego. Dallas is wettest in May and driest in January; San Diego is wettest in February and driest in June.
Dallas is the more humid of the two, averaging 69% relative humidity over the year against 57% in San Diego.
The most comfortable months in Dallas are April, May and October, when average temperatures are at their mildest.
San Diego is at its most pleasant around June, September and October, based on the mildest average temperatures of the year.
Dallas is the warmer city in 7 of the 11 months of the year. The gap is widest in June, about 6°C (10.8°F), and narrowest in October, about 0°C (0°F).
Dallas has the bigger seasonal swing, about 23.8°C (42.8°F) between its coldest and hottest months versus 14.1°C (25.4°F) in San Diego — so San Diego has the steadier, more even climate.
It depends what matters most to you: choose Dallas for warmer weather, pick San Diego if you prefer drier conditions and go for San Diego if you want lower humidity. There is no single "better" climate — it comes down to whether you value warmth, dryness or comfort most.
Every figure on this page is calculated from NASA POWER satellite climate data spanning 1981–2025 (45 years). The averages describe the long-term climate of Dallas and San Diego, not a single year's weather or a short-range forecast.
