San Mateo Weather
Town • San Francisco Bay Area
Downtown San Mateo is the busy middle of the Peninsula, a grid of restaurants and shops around the Caltrain station on First Avenue. Central Park and its Japanese Garden sit a few blocks south. The flatlands run east to the bay at Coyote Point and the Ryder Park and Seal Point shoreline, and the hills rise west toward Hillsborough and Highway 92. It sits closer to the Peninsula's cool-air gaps than the towns to its south, and on summer afternoons you can feel it.
Plan your week
10-Day Forecast
Hour by hour
Hourly Forecast
Current Conditions
Comfort Breakdown
San Mateo weather today and through the year
It's 54°F at San Mateo right now (feels like 51°F), with 5 mph wind and a comfort score of 78. Monday's forecast high at San Mateo is 58°F, 5°F below the mid November normal of 63°F. The best window today is 9 AM to noon, at about 55°F with a 3 mph wind (comfort 64).
September is the warmest month at San Mateo, with an average high of 72°F. December is the coldest, with an average low of 44°F. December is the wettest month (4.0 in.), out of about 20.2 in. a year. By typical temperature, wind, cloud, humidity, and rain odds, the most comfortable months at San Mateo are September, July, and August. The best hours are usually 11 AM to 2 PM in September, noon to 3 PM in July, and 11 AM to 2 PM in August.
San Mateo is about as far south as ocean air still reaches the bay side of the Peninsula easily. Marine air pours through the San Bruno Gap toward SFO and Burlingame just to the north. More spills over the low ridge along Highway 92 and through the Crystal Springs valley to the west. That keeps summer afternoons here noticeably cooler than in Redwood City or Atherton, which sit behind a higher, unbroken stretch of the Santa Cruz Mountains.
Forecast updated November 15, 2026 at 4:00 AM PST. Climate figures come from NOAA 1991-2020 normals. Hourly patterns come from NOAA's HRRR hourly analysis from September 2014 to April 2026.
What to expect at San Mateo in the next few days
No active National Weather Service alerts for this location.
Best time to go
The best window today is 9 AM to noon, at about 55°F with a 3 mph wind (comfort 64).
Best day this week
Of the next 7 days, Friday looks best for San Mateo, with a 61°F high and midday comfort near 79. Today looks weakest (51).
Rain
Next good chance of rain: today (76%, about 0.28 in.).
Live weather map
Weather around San Mateo right now
Overcast and 54° at San Mateo right now.
About the live weather map for San Mateo
The map centers on San Mateo and stacks fog, satellite clouds, and precipitation radar on one view. Clouds come from the GOES-West satellite and rain from NOAA radar, and both show current conditions. Fog comes from our HRRR-based fog model, and the slider steps through its forecast for the next 12 hours.
Dots mark nearby places with their current temperature, colored by comfort score. Use the layer buttons to turn any layer off, or open the full map for every destination in the region.
Nearby Temperature Comparison
Conditions at nearby San Francisco Bay Area destinations
Tip: Bay Area temperatures can change by 20 to 30°F over a short distance because of microclimates.
San Mateo vs nearby places
Typical summer conditions compared with San Mateo, from the same NOAA HRRR hourly record. The list shows the closest places, then nearby places whose climate differs the most.
| Place | Distance | Summer afternoons | Morning fog | Afternoon wind | Compared with San Mateo |
|---|---|---|---|---|---|
| Burlingame | 2.7 mi | same | 9% | 9 mph | a very similar climate |
| Foster City | 3 mi | -12°F | 14% | 12 mph | about 12°F cooler on summer afternoons and windier summer afternoons (12 vs 8 mph) |
| Belmont | 4 mi | same | 13% | 12 mph | windier summer afternoons (12 vs 8 mph) |
| Half Moon Bay | 8.9 mi | -12°F | 64% | 8 mph | more summer morning fog (64% vs 11% of morning hours) and about 12°F cooler on summer afternoons |
| Montara | 10.5 mi | -18°F | 60% | 8 mph | more summer morning fog (60% vs 11% of morning hours) and about 18°F cooler on summer afternoons |
| Moss Beach | 10.6 mi | -16°F | 66% | 9 mph | more summer morning fog (66% vs 11% of morning hours) and about 16°F cooler on summer afternoons |
Places with a climate like San Mateo's
- Corte Madera (27 mi away): similar temperatures through the year
- Ring Mountain Preserve (25 mi away): similar temperatures through the year
- San Rafael (31 mi away): similar temperatures through the year
Climate Dashboard
Current conditions vs. NOAA normals and recent destination baseline
What the San Mateo climate comparisons mean
These cards compare recent conditions at San Mateo with the available local baseline. Temperature and year-to-date rainfall use long-term normals when available. Fog, sunshine, wind, and comfort use the matching recent or modeled baseline identified on each card.
Positive and negative differences describe how San Mateo departs from its own usual pattern. They should not be read as a direct comparison with another city or as a forecast beyond the period shown.
San Mateo weather by month
September is the warmest month at San Mateo, with an average high of 72°F. December is the coldest, with an average low of 44°F. December is the wettest month (4.0 in.), out of about 20.2 in. a year. Morning fog peaks in December, when fog or low cloud covers 16% of the hours from 6 to 10 AM. June has the clearest middays, with clouds covering about 22% of the sky from 11 AM to 3 PM.
By typical temperature, wind, cloud, humidity, and rain odds, the most comfortable months at San Mateo are September, July, and August. The best hours are usually 11 AM to 2 PM in September, noon to 3 PM in July, and 11 AM to 2 PM in August.
| Month | Avg high | Avg low | Rain | Rainy days | Morning fog | Midday cloud | Afternoon wind | Daylight | Comfort |
|---|---|---|---|---|---|---|---|---|---|
| Jan | 58°F | 44°F | 4.0 in | 8 | 12% | 36% | 5 mph | 9.9 h | 59 |
| Feb | 60°F | 46°F | 3.9 in | 8 | 9% | 29% | 7 mph | 10.8 h | 61 |
| Mar | 63°F | 48°F | 3.0 in | 7 | 8% | 32% | 8 mph | 11.9 h | 65 |
| Apr | 65°F | 49°F | 1.4 in | 5 | 6% | 28% | 9 mph | 13.2 h | 73 |
| May | 67°F | 52°F | 0.6 in | 3 | 6% | 31% | 9 mph | 14.2 h | 76 |
| Jun | 70°F | 54°F | 0.2 in | 2 | 9% | 22% | 9 mph | 14.7 h | 88 |
| Jul | 71°F | 56°F | 0.0 in | 0 | 13% | 23% | 7 mph | 14.5 h | 89 |
| Aug | 71°F | 56°F | 0.0 in | 1 | 11% | 24% | 7 mph | 13.6 h | 89 |
| Sep | 72°F | 55°F | 0.1 in | 1 | 10% | 25% | 7 mph | 12.3 h | 91 |
| Oct | 70°F | 53°F | 0.9 in | 4 | 8% | 22% | 6 mph | 11.1 h | 84 |
| Nov | 63°F | 48°F | 1.9 in | 6 | 9% | 25% | 5 mph | 10.1 h | 75 |
| Dec | 58°F | 44°F | 4.0 in | 8 | 16% | 37% | 5 mph | 9.6 h | 58 |
Morning fog is the share of hours from 6 to 10 AM with fog or low cloud. Midday cloud is the average from 11 AM to 3 PM, and afternoon wind is the average from 1 to 5 PM. The highlighted rows are the most comfortable months.
In summer, recent daily NOAA readings at San Mateo average about 4°F warmer than the 1991-2020 normals. The normals average over a wider area that also covers nearby terrain. Read the monthly highs as a rough range, and use the recent months below for what San Mateo has actually seen.
What makes San Mateo's weather different
When the fog burns off
noonwhen December fog usually thins (19% foggy at 9 AM)
Fog or low cloud covers San Mateo in 19% of 9 AM hours in December, the foggiest month. It usually thins to a third of that by noon. April mornings are the least foggy (6%).
When the wind picks up
1 PMwhen afternoon wind builds, February–October
From February through October, wind at San Mateo typically builds after 1 PM. In May it peaks around 5 PM, averaging 11 mph with 13% of those hours windy, while mornings average 5 mph.
Microclimate
−12°FHalf Moon Bay, 8.9 mi away, on summer afternoons
Half Moon Bay, 8.9 miles away, runs about 12°F cooler than San Mateo on summer afternoons. It also has far more summer morning fog, 64% of morning hours compared with 11%.
Daylight
9.6–14.7 hof daylight, Dec to Jun
Days at San Mateo range from about 9.6 hours in December to 14.7 hours in June. In mid-June the sun sets around 8:30 PM, and in mid-December around 4:57 PM.
Seasons at San Mateo
- Warm seasonJul 30 – Oct 1 · highs 71°F+
The warm season lasts about 2.1 months, from Jul 30 to Oct 1, when the average high is 71°F or warmer. Highs peak around Sep 8 at about 72°F.
- Cool seasonNov 28 – Mar 3 · highs 62°F or lower
The cool season runs from Nov 28 to Mar 3, when the average high is 62°F or lower. The coldest nights come around Dec 8, with an average low near 44°F.
- Rainy seasonNov 19 – Mar 29 · 77% of the year's rain
The rainy season runs from Nov 19 to Mar 29, when a day has at least a 20% chance of measurable rain. That stretch brings 77% of the year's rain.
The dark line marks today. Season dates come from the smoothed daily NOAA 1991-2020 normals. Counting from Oct. 1, a typical year has its first inch of rain by Nov 2 and half of its annual total by Jan 25.
Days per year and extremes (Nov 1, 2024 to Oct 31, 2026)
This record runs from Nov 1, 2024 to Oct 31, 2026. Over this record, San Mateo averaged 9 days a year at 90°F or hotter and no freezing nights. It averaged 14 days a year with at least half an inch of rain and 1 afternoon with wind of 20 mph or more at 2 PM. About 43 mornings a year had 3 or more hours of fog or low cloud.
In the same record, the hottest day was Sep 9, 2026 (98°F) and the coldest night was Feb 10, 2025 (38°F). The wettest day was Nov 23, 2024 (2.48 in.), and the strongest 2 PM gust was 49 mph on Mar 12, 2025.
- 9days at 90°F or hotter
- 0nights at or below freezing
- 14days with ½ in. of rain or more
- 1afternoon with 20+ mph wind
- 43mornings with 3+ hours of fog or low cloud
- Hottest day98°FSep 9, 2026
- Coldest night38°FFeb 10, 2025
- Wettest day2.48 inNov 23, 2024
- Strongest 2 PM gust49 mphMar 12, 2025
What shapes San Mateo's weather
Summer days in San Mateo follow a pattern. The marine layer is the cool, moist air off the ocean that forms low cloud. On some mornings it is deep enough to ride over the western hills and hang over downtown until late morning. Most afternoons are sunny, and a northwest sea breeze builds as the day goes on. It is strongest out on the bay at Coyote Point, which is why that shoreline draws windsurfers.
The best weather downtown tends to come in early fall, when the summer sea-breeze pattern weakens and afternoons turn warm and still. Winter storms arrive from the Pacific over the hills to the west, which catch a little more rain than the flats. Clear, calm nights between storms turn chilly downtown.
Tips for visiting San Mateo
Take Caltrain to First Avenue
San Mateo station is at 385 First Avenue on the edge of downtown, with an elevator and connections to SamTrans buses.
Visit the Japanese Garden in Central Park
Central Park, at 50 E. Fifth Avenue, has a Japanese Garden a few blocks south of the Caltrain station.
Expect wind at the shoreline
Ryder Park on the bay has a kayak and windsurf launch. The afternoon breeze there is usually much stronger than on downtown streets.
Watch SFO arrivals at Coyote Point
Coyote Point Recreation Area, northeast of downtown on the bay, has a beach promenade, the CuriOdyssey science center, and views of planes at San Francisco International Airport.
San Mateo through the seasons
- Spring (March–May)
- Spring brings breezy days between the last storms, and the afternoon sea breeze gets stronger as the season goes on.
- Summer (June–August)
- Some mornings start gray, and afternoons turn sunny and breezy. Downtown streets and Central Park are calmer than the bayfront.
- Fall (September–October)
- September and early October are often the warmest weeks downtown, with lighter afternoon wind. It is the best time for outdoor tables.
- Winter (November–February)
- Winter is the rainy season. Storms come in over the western hills, and still, clear nights after a storm are cold on the flats.
Activities and the weather that matters
- Downtown dining: Downtown's restaurants work year-round. Outdoor tables are most pleasant on fall afternoons, when the sea breeze is light.
- Windsurfing at Coyote Point: The county lists windsurfing as an activity at Coyote Point. It depends on the afternoon sea breeze that builds in spring and summer.
- Biking the Bay Trail: The trail follows the shoreline through Ryder and Seal Point parks to Foster City. Ride in the morning to beat the headwind.
- Picnics in Central Park: Four separate picnic areas a few blocks from downtown make this the sheltered option on a breezy summer afternoon.
Official sources and current conditions
- City of San Mateo: Central Park
- San Mateo County Parks: Coyote Point Recreation Area
- Caltrain: San Mateo station
- San Francisco Bay Trail: Burlingame to Redwood Shores
Numbers on this page come from NOAA data. The text draws on the official sources linked above.
Historical Climate Data
Long-term weather patterns and climate data
Data sources: Recent temperatures come from NOAA URMA and recent precipitation from NOAA Stage IV. Fog, cloud, wind, humidity, and sunshine come from NOAA HRRR, and long-term baselines from NOAA 1991-2020 climate normals.
Climate Overview
Based on NOAA 30-year temperature/rain normals (1991-2020) with recent fog/sun baseline
🌟 Best Months to Visit
⚠️ Challenging Months
Monthly Breakdown
| Month | Comfort | High/Low | ☀️ Sun | 🌫️ Fog | 💧 Rain | Perfect |
|---|---|---|---|---|---|---|
| November 2024 | 82 | 62.8° / 48.3° | 6.5h | 2d | 3.9" | 22 |
| December 2024 | 73 | 60.2° / 47.5° | 4.9h | 5d | 5.13" | 13 |
| January 2025 | 84 | 60.1° / 44.2° | 6.5h | 2d | 0.15" | 21 |
| February 2025 | 76 | 61.3° / 46° | 6.6h | 4d | 5.92" | 16 |
| March 2025 | 83 | 62.2° / 47.2° | 8.2h | 0d | 1.82" | 21 |
| April 2025 | 90 | 66.5° / 48.4° | 9.4h | 0d | 0.39" | 25 |
| May 2025 | 94 | 71.5° / 51.5° | 12.1h | 0d | 0.15" | 30 |
| June 2025 | 96 | 71.1° / 52.7° | 12.4h | 1d | 0" | 30 |
| July 2025 | 94 | 71.9° / 55.4° | 11.5h | 1d | 0" | 31 |
| August 2025 | 95 | 78.9° / 57.6° | 11.1h | 1d | 0" | 31 |
| September 2025 | 91 | 77.6° / 60.3° | 9.5h | 2d | 0.07" | 29 |
| October 2025 | 89 | 72° / 55.1° | 7.9h | 3d | 0.99" | 28 |
| November 2025 | 80 | 64.9° / 51.3° | 6.4h | 8d | 3.2" | 15 |
| December 2025 | 71 | 57.9° / 47.2° | 4.9h | 9d | 3.9" | 7 |
| January 2026 | 81 | 61.5° / 46.3° | 6.6h | 2d | 4.6" | 22 |
| February 2026 | 80 | 63.6° / 48.4° | 6.6h | 3d | 3.48" | 19 |
| March 2026 | 94 | 76° / 52.7° | 9.5h | 0d | 0.02" | 30 |
| April 2026 | 89 | 67.5° / 51.1° | 9.3h | 2d | 3.16" | 24 |
| May 2026 | 93 | 69.8° / 53° | 11.6h | 2d | 0.26" | 31 |
| June 2026 | 95 | 73.9° / 55.4° | 12.3h | 0d | 0" | 30 |
| July 2026 | 95 | 75° / 56.9° | 11.5h | 1d | 0" | 31 |
| August 2026 | 93 | 76° / 57.2° | 10.7h | 3d | 0" | 31 |
| September 2026 | 93 | 76.9° / 57.3° | 10h | 2d | 0.05" | 30 |
| October 2026 | 92 | 75.4° / 54.8° | 8.2h | 1d | 0.14" | 29 |
Climate Trends
Average Temperature by Month
About the San Mateo climate charts
The temperature chart compares average monthly highs and lows at San Mateo, showing both the seasonal cycle and the typical day-to-night range. The comfort chart summarizes how often the combined weather pattern is favorable rather than judging temperature alone.
Precipitation shows the total recorded or modeled rainfall for each month at San Mateo. Sunshine compares average bright-sky hours with the daylight available, while fog shows the average number of morning fog or low-cloud hours per day. Switch between the chart tabs to compare the same months across each measure.
Hourly Temperature, Fog, Wind, Cloud Cover, and Solar Radiation Patterns
Average local hour by month from 2014-09-30 to 2026-04-30
- Temperature: At San Mateo, the warmest typical hour is 3 PM in August (77°F). The coldest is 7 AM in January (46°F).
- Fog: Fog or low cloud covers San Mateo in 19% of 9 AM hours in December, the foggiest month. It usually thins to a third of that by noon. April mornings are the least foggy (6%).
- Wind: From February through October, wind at San Mateo typically builds after 1 PM. In May it peaks around 5 PM, averaging 11 mph with 13% of those hours windy, while mornings average 5 mph.
- Cloud Cover: June middays are the clearest at San Mateo (22% average cloud cover), and December middays are the cloudiest (37%).
- Solar Radiation: The strongest typical sun at San Mateo comes at 1 PM in July, averaging 950 W/m².
How to read the hourly heatmaps for San Mateo
This heatmap shows how average temperature at San Mateo changes by hour and month. Read left to right for the seasons and top to bottom for the time of day. Warmer colors mark the usual afternoon peaks, and cooler colors show overnight and winter lows.
This heatmap shows when fog or low cloud is most likely at San Mateo. Darker cells mark the months and hours when fog has been most common. They help separate overnight or morning fog from cloud that tends to linger into the afternoon.
This heatmap shows the typical hourly wind pattern at San Mateo through the year. It makes recurring afternoon wind, calmer overnight periods, and seasonal changes easier to compare than a single daily wind value.
This heatmap shows average cloud cover at San Mateo for every month and hour. Use it to see whether cloudiness is mainly an overnight and morning pattern or commonly persists during the part of the day you plan to visit.
This heatmap shows the average solar radiation reaching San Mateo by month and hour. Brighter cells indicate the strongest typical sun, while muted cells can reflect nighttime, shorter winter days, cloud cover, smoke, or terrain shading.
Each cell combines one month with one local hour. Hover over or focus on a cell for its value and sample coverage. The red marker shows the current month and hour.
How recent months compared at San Mateo
- October 2026 recap: October 2026 at San Mateo averaged a high of 75°F, 5°F warmer than the 1991-2020 normal of 70°F. It brought 0.14 in. of rain, compared with a normal of 0.93 in.
- Rain year: The 2025-26 rain year (Oct. 1 to Sep. 30) brought 19.7 in. of rain to San Mateo, 97% of the 20.2 in. normal.
Location Details
San Mateo weather questions
Everything you need to know about weather and visiting San Mateo
What is the weather like at San Mateo today?
It's 54°F at San Mateo right now, with a comfort score of 78 (great). Monday's forecast high at San Mateo is 58°F, 5°F below the mid November normal of 63°F. The best window today is 9 AM to noon, at about 55°F with a 3 mph wind (comfort 64).
What is the best month to visit San Mateo?
By typical temperature, wind, cloud, humidity, and rain odds, the most comfortable months at San Mateo are September, July, and August. The best hours are usually 11 AM to 2 PM in September, noon to 3 PM in July, and 11 AM to 2 PM in August. The warm season lasts about 2.1 months, from Jul 30 to Oct 1, when the average high is 71°F or warmer. Highs peak around Sep 8 at about 72°F.
What are the warmest and coldest months at San Mateo?
September is the warmest month at San Mateo, with an average high of 72°F. December is the coldest, with an average low of 44°F.
When does the fog burn off at San Mateo?
Fog or low cloud covers San Mateo in 19% of 9 AM hours in December, the foggiest month. It usually thins to a third of that by noon. April mornings are the least foggy (6%).
When is it windiest at San Mateo?
From February through October, wind at San Mateo typically builds after 1 PM. In May it peaks around 5 PM, averaging 11 mph with 13% of those hours windy, while mornings average 5 mph.
How much rain does San Mateo get?
December is the wettest month (4.0 in.), out of about 20.2 in. a year. The rainy season runs from Nov 19 to Mar 29, when a day has at least a 20% chance of measurable rain. That stretch brings 77% of the year's rain. The 2025-26 rain year (Oct. 1 to Sep. 30) brought 19.7 in. of rain to San Mateo, 97% of the 20.2 in. normal.
How does San Mateo weather compare with Half Moon Bay?
Half Moon Bay, 8.9 miles away, runs about 12°F cooler than San Mateo on summer afternoons. It also has far more summer morning fog, 64% of morning hours compared with 11%.
What kind of place is San Mateo?
Downtown San Mateo is the busy middle of the Peninsula, a grid of restaurants and shops around the Caltrain station on First Avenue. Central Park and its Japanese Garden sit a few blocks south. The flatlands run east to the bay at Coyote Point and the Ryder Park and Seal Point shoreline, and the hills rise west toward Hillsborough and Highway 92. It sits closer to the Peninsula's cool-air gaps than the towns to its south, and on summer afternoons you can feel it.
What is San Mateo weather like in November?
November at San Mateo averages a high of 63°F and a low of 48°F, with 1.9 in. of rain over about 6 rainy days. Afternoon wind averages 5 mph.
More about San Mateo weather
Guides that explain the weather here and nearby
- El Niño in the Bay Area and California: 1997-98 vs. 2026-27
- Bomb Cyclones: When Rapidly Intensifying Storms Hit the Bay Area
- What Are Atmospheric Rivers? How They Drench the Bay Area
- How Atmospheric Rivers Impact the Bay Area
- Half Moon Bay Weather: Coastal Fog and Pacific Exposure
- Driving in Bay Area Fog: Visibility and Safety Tips
Data sources and methods
- Monthly temperatures and precipitation: NOAA 1991-2020 normals.
- Fog, cloud, wind, sun, and comfort by hour and month: NOAA's HRRR hourly analysis from September 2014 to April 2026.
- Daily records and recent months: NOAA URMA and HRRR analyses, plus NOAA Stage IV precipitation.
- Nearby comparisons and regional rankings use the same hourly HRRR summaries for every destination in the region.
- Alerts: National Weather Service. Tides and ocean temperature: NOAA CO-OPS, where shown.
- All statements on this page are computed from these datasets, apart from the “What shapes the weather” guide, which cites its sources inline.
- Caltrain, San Mateo station (accessed 2026-10-27)
- City of San Mateo, Central Park (accessed 2026-10-27)
- San Mateo County Parks, Coyote Point Recreation Area (accessed 2026-10-27)
- MTC, San Francisco Bay Trail Map 4: Burlingame to Redwood Shores (accessed 2026-10-27)
Rendered 2026-11-15T12:04:22.734Z.