Dublin Weather

May is the clear winner. May 2025 recorded a comfort score of 91 out of 100, the highest in the 18-month dataset, with an average high of 74 degrees, a low of 51, and zero rainfall. That combination of warm afternoons, cool evenings, and long days hitting 12.7 hours of sunshine is about as good as the Bay Area gets. April is nearly as strong, scoring 89 with highs in the low 70s and minimal rain. July and August are also excellent for pure warmth, consistently reaching the high 70s to low 80s with comfort scores around 88 to 90. The summer months in Dublin run warmer than coastal Bay Area towns because the Tri-Valley sits inland, sheltered from the marine layer that suppresses temperatures on the coast. If you want reliable heat without the coastal fog and wind, any month from May through September will serve you well here. The 271 perfect days per year in the data says something: Dublin delivers on its sunny, warm reputation more consistently than people might expect.

Dublin gets genuinely hot. Highs in June, July, and August regularly land in the upper 70s to low 80s on average, but individual days can push into the 90s and occasionally past 100 degrees during heat events. The 18-month data shows average summer highs around 78 to 81 degrees, but those are averages across all days, including cooler ones. The Tri-Valley's geography is the key factor: Dublin sits east of the hills that block marine air from the bay, so the cool ocean influence that keeps San Francisco and Oakland moderate in summer barely reaches here. Heat builds up through the day without much relief until nighttime. One thing that saves Dublin from being oppressive: nights cool down reliably. Lows stay in the mid-50s through summer, so the mornings are pleasant even when the afternoon is scorching. September averages a high of 79 degrees, rivaling July and August, which is a pattern worth knowing if you are planning a visit. For context on why late summer heat tends to linger in the Bay Area, see why September is often hotter than July in the Bay Area.

Dublin winters are mild compared to most of the country but can be cold by Bay Area standards, especially at night. January 2025 was the coldest month in the dataset, with an average high of 59.8 degrees and a low of 42. December 2025 was the gloomiest, scoring a comfort score of just 70 with only 6.5 hours of sunshine per day and 2.75 inches of rain. Lows in the upper 30s are not uncommon in December and January, and frost does occasionally occur at Dublin's 361-foot elevation, though it is rare and light. The bigger winter story is rain and cloud cover rather than extreme cold. November 2024 dropped 4.94 inches of rain, and January 2025 logged 5.59 inches, both well above the summer totals of near-zero precipitation. Dublin is noticeably colder on winter nights than coastal spots like Alameda or San Jose, because the inland valley can trap cold air after sunset. That said, afternoons in the upper 50s with some winter sun are genuinely comfortable for outdoor walks. Pack layers for early morning and evening, and bring rain gear from November through March.

Dublin's rainy season runs from late October through March, with November through February being the wet core. January 2025 was the wettest month in the dataset at 5.59 inches, followed by November 2024 at 4.94 inches and February 2025 at 3.87 inches. October is the transition month: October 2024 brought 2.69 inches after a completely dry summer, while October 2025 jumped to 4.38 inches. The rain pattern here is typical Northern California winter: storms blow through over one to three days, often followed by clear stretches with crisp light and good visibility toward the hills. Dublin's 361-foot elevation means it occasionally sees light snow during the strongest winter storms, something flatland Bay Area towns rarely experience. With roughly 77 rainy days per year, the dry season from May through September is genuinely rain-free. May 2025 logged zero inches, and the summer months are reliable for outdoor planning. For a broader look at Bay Area rain patterns, see the rainiest months in the Bay Area.

Dublin gets some morning fog, averaging 2.1 hours per day across the full dataset, but it is a different animal than the coastal fog that blankets San Francisco and the western hills. The marine layer rarely penetrates this far inland with full force. What Dublin sees is more often ground fog that forms in the valley overnight when temperatures drop and the air is damp, particularly in fall and early winter. October and November 2025 were the foggiest months in this dataset, averaging 3.1 to 3.2 hours per morning. Summer fog is lighter, typically 1.9 to 2.2 hours per day, and it burns off faster once the sun rises and heats the inland air. September 2024 was the clearest month at just 1.0 hour of morning fog per day. The key difference from the coast: Dublin's morning fog is not driven by cold ocean upwelling and sea breeze the way San Francisco's famous fog is. It forms locally and dissipates locally. By late morning on most days, the sky over Dublin is clear and warming quickly. To understand the mechanics behind Bay Area fog patterns, see why morning fog forms in the Bay Area.

Dublin, Pleasanton, and Danville all share the Tri-Valley climate and sit within a few miles of each other, so their weather is closely matched. All three run noticeably warmer than coastal Bay Area towns in summer and cooler at night than urban areas like San Jose or Oakland. The differences between them are subtle. Danville sits slightly further south and closer to the hills, which can trap heat on summer afternoons and funnel afternoon wind through the valley. Pleasanton is Dublin's immediate neighbor to the south and nearly identical in climate profile. If you are choosing between Tri-Valley destinations based purely on weather, the gap will be small: maybe 2 to 3 degrees between a shaded valley floor location and a south-facing hillside neighborhood. The bigger distinction is between any Tri-Valley town and somewhere like San Francisco or Half Moon Bay. Where the coast might hit 62 degrees on a July afternoon, Dublin is routinely 15 to 20 degrees warmer. The Bay Area's microclimate variation is one of the most dramatic in the country, and the Tri-Valley illustrates exactly why the inland side of the coastal hills is a completely different experience.

For about eight months of the year, yes, without much reservation. From April through October, Dublin's afternoon temperatures are reliably in the upper 60s to low 80s, comfortable for outdoor seating in direct sun. April 2025 averaged a high of 72.5 degrees with a comfort score of 89, and May through September all run similarly warm. Summer afternoons are the prime window for outdoor dining here, with highs in the high 70s and the kind of dry heat that makes sitting outside genuinely pleasant. Evenings cool off faster than you might expect since the inland valley radiates heat quickly after sunset, so plan dinner patios for early evening rather than 8 or 9 p.m. in summer. Winter outdoor dining is possible but requires commitment. December and January average highs in the upper 50s, and evenings drop to the low 40s. A heated patio with good overhead coverage makes it workable, but it is not the experience you get in May. November and December also bring the most cloud cover, which makes outdoor seating feel colder than the thermometer suggests. The 271 perfect days per year the data shows means Dublin has a generous window for outdoor activities, dining included.

Dublin's temperature swings between morning and afternoon are bigger than most people expect, especially in spring and fall. A day that starts at 49 degrees can finish at 74, and that 25-degree shift means layering is the most practical approach. In summer, light clothing works for midday and afternoon, but a light jacket is worth bringing for evenings, when the valley cools quickly after sunset. Sunscreen is essential from April through September: Dublin logs 12 to 12.7 hours of sunshine per day at peak, and UV exposure at this elevation and latitude is higher than it feels. In fall and winter, a waterproof outer layer matters more than heavy insulation. The temperatures rarely demand a thick winter coat, but damp air combined with wind on a December afternoon at 55 degrees can feel cold enough to be unpleasant without a wind-blocking shell. Comfortable walking shoes that can handle wet pavement are smart from October through March. The general principle that applies across the Bay Area applies here too: check the daily low, not just the high, and dress in layers for the Bay Area's variable conditions.

Dublin averages 9.4 hours of sunshine per day across the 18-month dataset, which is strong for the Bay Area. The peak months are May and April, both hitting 12.3 to 12.7 hours of sunshine per day, with June and July close behind at 11.3 to 12.3 hours. Even with morning fog factored in, the afternoon clearing rate in Dublin is reliable: the inland heat pulls the marine layer back toward the coast by late morning on most summer days. The low point is the winter cluster from November through January, where sunshine drops to 6.5 to 6.6 hours per day and storm systems reduce afternoon brightness. December 2025 was the worst on record in this dataset at just 6.5 hours per day. Even so, those winter numbers compare favorably to cities further north, which average far fewer clear hours in December. Dublin's roughly 271 perfect days per year puts it in genuinely sunny territory for a Bay Area location. The combination of inland positioning, modest elevation, and the Tri-Valley's shelter from persistent coastal overcast makes Dublin consistently sunnier than the coast and the western hills.

December 2025 recorded the lowest comfort score in the dataset at 70, making it the toughest month for weather. November and January are close behind, both landing around 73 to 76 comfort, with January 2025 hitting the wettest conditions at 5.59 inches of rain and only 6.6 hours of sunshine per day. The problem in these months is not extreme cold: lows in the low 40s are uncomfortable but manageable. The issue is the combination of persistent gray skies, frequent rain, and short days that never quite warm up enough to feel inviting. November 2024 and 2025 both brought around 4 to 5 inches of rain each. If you do visit in winter, midday on a clear post-storm day can be pleasant, with temperatures reaching the low 60s and good visibility toward the hills. San Ramon and Castro Valley see similar winter conditions, so there is no obvious nearby escape from the seasonal gray within the Tri-Valley. The contrast with the best months is stark: the 21-point gap between December's comfort score of 70 and May's score of 91 captures just how different Dublin can feel across the calendar year.