Middletown Weather
Town • San Francisco Bay Area
Middletown is a small unincorporated town in southern Lake County, set in a valley at the north foot of Mount St. Helena. Highway 29 comes down from Calistoga here, and Highway 175 heads up toward Cobb. For many Bay Area drivers it is the first stop over the mountain. The 2015 Valley Fire swept from Cobb down through town in a single day. Middletown is also home to the free Calpine Geothermal Visitor Center, which explains the steam field at The Geysers in the mountains to the west.
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10-Day Forecast
Hour by hour
Hourly Forecast
Current Conditions
Comfort Breakdown
Middletown weather today and through the year
It's 49°F at Middletown right now (feels like 47°F), with 2 mph wind and a comfort score of 71. Today's forecast high at Middletown is 57°F, 7°F below the mid November normal of 64°F. No fog in the forecast for today at Middletown. In November, 26% of morning hours here are foggy on average. The best window today is 2 PM to 5 PM, at about 47°F with a 3 mph wind (comfort 61).
July is the warmest month at Middletown, with an average high of 91°F. December is the coldest, with an average low of 36°F. December is the wettest month (8.6 in.), out of about 40.7 in. a year. By typical temperature, wind, cloud, humidity, and rain odds, the most comfortable months at Middletown are May, September, and October. The best hours are usually 10 AM to 1 PM in May, 9 AM to noon in September, and 11 AM to 2 PM in October.
Highway 29's climb over Mount St. Helena changes the weather completely. The mountain and the Mayacamas ridge to the west block the marine air that cools the Napa and Sonoma valleys. Middletown's summer is fully inland, with mostly clear mornings and long, hot afternoons. In a June 2022 heat advisory for southern Lake County, the National Weather Service forecast Middletown as the hottest spot.
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 Middletown in the next few days
No active National Weather Service alerts for this location.
Fog
No fog in the forecast for today at Middletown. In November, 26% of morning hours here are foggy on average.
Best time to go
The best window today is 2 PM to 5 PM, at about 47°F with a 3 mph wind (comfort 61).
Best day this week
Of the next 7 days, Friday looks best for Middletown, with a 56°F high and midday comfort near 68. Wednesday looks weakest (50).
Rain
Next good chance of rain: today (84%, about 0.37 in.).
Live weather map
Weather around Middletown right now
Overcast and 49° at Middletown right now.
About the live weather map for Middletown
The map centers on Middletown 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.
Middletown vs nearby places
Typical summer conditions compared with Middletown, 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 Middletown |
|---|---|---|---|---|---|
| Robert Louis Stevenson State Park | 6.6 mi | -9°F | 8% | 10 mph | about 9°F cooler on summer afternoons |
| Boggs Mountain Demonstration State Forest | 6.8 mi | -7°F | 5% | 6 mph | about 7°F cooler on summer afternoons and calmer summer afternoons (6 vs 10 mph) |
| Cobb Mountain Area | 8 mi | -6°F | 6% | 7 mph | about 6°F cooler on summer afternoons and about 35% more rain a year |
| Sugarloaf Ridge State Park | 22.1 mi | -9°F | 17% | 10 mph | about 9°F cooler on summer afternoons |
| Santa Rosa | 22.2 mi | -7°F | 33% | 9 mph | about 7°F cooler on summer afternoons and more summer morning fog (33% vs 17% of morning hours) |
| Lake Berryessa | 23.4 mi | +1°F | 1% | 8 mph | less summer morning fog (1% vs 17% of morning hours) and about 34% less rain a year |
Places with a climate like Middletown's
- Cloverdale (22 mi away): nearly the same temperatures every month
- Pope Valley (14 mi away): similar temperatures through the year
- Geyserville (16 mi away): similar temperatures through the year
Climate Dashboard
Current conditions vs. NOAA normals and recent destination baseline
What the Middletown climate comparisons mean
These cards compare recent conditions at Middletown 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 Middletown 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.
Middletown weather by month
July is the warmest month at Middletown, with an average high of 91°F. December is the coldest, with an average low of 36°F. December is the wettest month (8.6 in.), out of about 40.7 in. a year. Morning fog peaks in December, when fog or low cloud covers 38% of the hours from 6 to 10 AM. July has the clearest middays, with clouds covering about 2% of the sky from 11 AM to 3 PM.
By typical temperature, wind, cloud, humidity, and rain odds, the most comfortable months at Middletown are May, September, and October. The best hours are usually 10 AM to 1 PM in May, 9 AM to noon in September, and 11 AM to 2 PM in October.
| Month | Avg high | Avg low | Rain | Rainy days | Morning fog | Midday cloud | Afternoon wind | Daylight | Comfort |
|---|---|---|---|---|---|---|---|---|---|
| Jan | 56°F | 36°F | 8.6 in | 12 | 36% | 34% | 5 mph | 9.8 h | 31 |
| Feb | 59°F | 38°F | 7.7 in | 12 | 21% | 28% | 7 mph | 10.7 h | 43 |
| Mar | 63°F | 40°F | 5.4 in | 10 | 23% | 31% | 7 mph | 11.9 h | 50 |
| Apr | 69°F | 42°F | 2.6 in | 7 | 17% | 22% | 8 mph | 13.2 h | 72 |
| May | 76°F | 47°F | 1.5 in | 5 | 18% | 14% | 9 mph | 14.3 h | 84 |
| Jun | 85°F | 52°F | 0.3 in | 2 | 11% | 4% | 11 mph | 14.9 h | 79 |
| Jul | 91°F | 56°F | 0.0 in | 0 | 17% | 2% | 11 mph | 14.6 h | 76 |
| Aug | 90°F | 55°F | 0.0 in | 1 | 24% | 4% | 10 mph | 13.6 h | 77 |
| Sep | 87°F | 51°F | 0.1 in | 2 | 20% | 8% | 8 mph | 12.3 h | 84 |
| Oct | 77°F | 46°F | 1.8 in | 6 | 24% | 14% | 7 mph | 11.1 h | 84 |
| Nov | 64°F | 40°F | 4.0 in | 8 | 26% | 21% | 5 mph | 10.0 h | 68 |
| Dec | 56°F | 36°F | 8.6 in | 12 | 38% | 36% | 5 mph | 9.5 h | 29 |
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.
What makes Middletown's weather different
Among the 163 San Francisco Bay Area towns we track, Middletown has the coldest winter nights.
- #1of 163
coldest winter nightsamong San Francisco Bay Area towns
When the fog burns off
4 PMwhen December fog usually thins (44% foggy at 5 AM)
Fog or low cloud covers Middletown in 44% of 5 AM hours in December, the foggiest month. It usually thins to a third of that by 4 PM, but 15% of mid-afternoon hours are still foggy. June mornings are the least foggy (11%).
When the wind picks up
2 PMwhen afternoon wind builds, April–September
From April through September, wind at Middletown typically builds after 2 PM. In July it peaks around 5 PM, averaging 13 mph with 8% of those hours windy, while mornings average 4 mph.
Hot hours
8 habove 85°F on a typical July afternoon
In July, the average temperature stays at or above 85°F for 8 hours a day.
Elevation
−6°Fsummer afternoons at Cobb Mountain Area, 1,690 ft up
Cobb Mountain Area sits 1,690 ft higher, 8 miles away. Its summer highs average 6°F cooler and its winter lows 1°F milder than Middletown.
Daylight
9.5–14.9 hof daylight, Dec to Jun
Days at Middletown range from about 9.5 hours in December to 14.9 hours in June. In mid-June the sun sets around 8:37 PM, and in mid-December around 4:55 PM.
Seasons at Middletown
- Warm seasonJun 26 – Sep 23 · highs 86°F+
The warm season lasts about 3 months, from Jun 26 to Sep 23, when the average high is 86°F or warmer. Highs peak around Jul 8 at about 91°F.
- Hot afternoonsJun 24 – Sep 25 · highs 85°F+
Average highs reach 85°F or more from Jun 24 to Sep 25.
- Cool seasonNov 28 – Feb 28 · highs 61°F or lower
The cool season runs from Nov 28 to Feb 28, when the average high is 61°F or lower. The coldest nights come around Dec 8, with an average low near 36°F.
- Rainy seasonOct 26 – Apr 21 · 90% of the year's rain
The rainy season runs from Oct 26 to Apr 21, when a day has at least a 21% chance of measurable rain. That stretch brings 90% 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 Oct 18 and half of its annual total by Jan 22.
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, Middletown averaged 63 days a year at 90°F or hotter and 10 nights a year at or below freezing. It averaged 26 days a year with at least half an inch of rain and 3 afternoons with wind of 20 mph or more at 2 PM. About 91 mornings a year had 3 or more hours of fog or low cloud.
In the same record, the hottest day was Aug 8, 2026 (103°F) and the coldest night was Feb 11, 2025 (27°F). The wettest day was Nov 21, 2024 (5.53 in.), and the strongest 2 PM gust was 49 mph on Feb 13, 2025.
- 63days at 90°F or hotter
- 10nights at or below freezing
- 26days with ½ in. of rain or more
- 3afternoons with 20+ mph wind
- 91mornings with 3+ hours of fog or low cloud
- Hottest day103°FAug 8, 2026
- Coldest night27°FFeb 11, 2025
- Wettest day5.53 inNov 21, 2024
- Strongest 2 PM gust49 mphFeb 13, 2025
What shapes Middletown's weather
Higher ground rings Middletown, with Mount St. Helena to the south and Cobb Mountain and the Mayacamas to the northwest. After sunset, cool air drains off those slopes and pools on the valley floor, so nights cool off far more than the afternoon heat would suggest. Frost is common on clear winter mornings, and on those nights the valley floor is usually colder than homes partway up the hills toward Cobb.
Winter storms from the southwest have to rise over Mount St. Helena and the Mayacamas before reaching town, and they drop heavy rain on those slopes. In cold storms, snow whitens Mount St. Helena and Cobb Mountain and can reach the higher roads around Cobb, but it rarely lasts on Middletown's valley floor.
Fire is part of the climate here. Long dry summers, brush-covered slopes, and wind gave the 2015 Valley Fire the speed to run from Cobb down through Middletown in one day.
Tips for visiting Middletown
Plan outdoor time for mornings
Summer afternoons here are hot enough to bring heat advisories, so hike, bike or garden before midday. Carry more water than you would in the Napa Valley.
Cool off at the geothermal center
The Calpine Geothermal Visitor Center at 15500 Central Park Road is free. It opens Fridays and Saturdays from 10 a.m. to 5 p.m. Most tours of The Geysers start there.
Hike Trailside Nature Preserve early
The 107-acre preserve on the west end of town, at the base of Sugarloaf Peak, is open dawn to dusk and has woodland, grassland, and seasonal wetlands.
Check Highways 29 and 175 in storms
Chain controls, rules that require tire chains, can go up on the higher roads in cold storms. Check Caltrans QuickMap for them and for closures, or call the Caltrans highway information line at (800) 427-7623.
Register for LakeCoAlerts
Sign up for LakeCoAlerts to get the county's emergency messages by phone. Before fire season, look up your evacuation zone on Genasys Protect, which needs no account.
Middletown through the seasons
- Spring (March–May)
- The hills are green and the vernal pools and seasonal wetlands at Trailside Nature Preserve hold water after winter rains, before the heat arrives.
- Summer (June–August)
- Summer is hot and dry, with almost no cooling from the ocean. Heat advisories for southern Lake County can name Middletown as the hottest spot.
- Fall (September–November)
- September is still hot, and fire season lasts until the first soaking rain. Keep an eye on Red Flag Warnings, the Weather Service alerts for critical fire weather.
- Winter (December–February)
- Winter is the wet season, with cold, often frosty mornings. Chain controls can go up on Highway 175 through Cobb during cold storms.
Activities and the weather that matters
- Hiking at Trailside Nature Preserve: Spring mornings are best, when the wetlands are full. Summer afternoons are too hot for most hikers.
- Geothermal visitor center and tours: The center is an indoor stop that works in any weather, and a good way to spend a hot afternoon.
- Driving over Mount St. Helena on Highway 29: Views are clearest on dry winter days after a storm passes. Rain, fog, or snow on the grade makes the drive slow.
Official sources and current conditions
- Lake County: Lake Co Ready (alerts and evacuation zones)
- Calpine Geothermal Visitor Center
- Caltrans winter driving and road conditions
- National Weather Service forecast: Middletown
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 | 75 | 60.3° / 39.5° | 6.2h | 7d | 16.65" | 15 |
| December 2024 | 69 | 59.8° / 40.5° | 5.2h | 12d | 10.55" | 12 |
| January 2025 | 83 | 61.5° / 38° | 7.3h | 7d | 0.62" | 21 |
| February 2025 | 74 | 59.3° / 39.4° | 6.5h | 7d | 15.24" | 14 |
| March 2025 | 77 | 59.3° / 40.9° | 7.9h | 7d | 5.9" | 17 |
| April 2025 | 89 | 68.9° / 44.5° | 9.7h | 6d | 0.96" | 24 |
| May 2025 | 94 | 78.5° / 50.1° | 12.5h | 0d | 0.25" | 31 |
| June 2025 | 92 | 86.8° / 53.9° | 13h | 0d | 0" | 30 |
| July 2025 | 92 | 87.7° / 55.5° | 12.6h | 0d | 0" | 30 |
| August 2025 | 84 | 93° / 57.6° | 11.6h | 2d | 0" | 23 |
| September 2025 | 88 | 84° / 56.5° | 9.6h | 3d | 0.31" | 26 |
| October 2025 | 84 | 72.1° / 48.2° | 7.4h | 13d | 2.23" | 24 |
| November 2025 | 78 | 65.6° / 44.2° | 6.3h | 12d | 6.85" | 15 |
| December 2025 | 69 | 61.7° / 41.1° | 4.9h | 21d | 11.02" | 13 |
| January 2026 | 79 | 63.7° / 40.9° | 6.6h | 6d | 7.67" | 21 |
| February 2026 | 75 | 62° / 41.6° | 6.3h | 7d | 6.53" | 13 |
| March 2026 | 94 | 77.1° / 47.4° | 9.8h | 2d | 0" | 30 |
| April 2026 | 84 | 66.2° / 44.6° | 9.2h | 5d | 6.14" | 22 |
| May 2026 | 92 | 76.3° / 50.4° | 11.7h | 2d | 1.21" | 28 |
| June 2026 | 92 | 86.4° / 55° | 12.9h | 0d | 0" | 29 |
| July 2026 | 89 | 90.7° / 55.8° | 12.4h | 0d | 0" | 29 |
| August 2026 | 85 | 91.6° / 55.8° | 11.2h | 4d | 0" | 22 |
| September 2026 | 88 | 83.4° / 51.6° | 10.3h | 6d | 0.5" | 28 |
| October 2026 | 87 | 79.9° / 47.5° | 8.4h | 2d | 0.01" | 22 |
Climate Trends
Average Temperature by Month
About the Middletown climate charts
The temperature chart compares average monthly highs and lows at Middletown, 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 Middletown. 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 Middletown, the warmest typical hour is 3 PM in July (91°F). The coldest is 7 AM in December (43°F).
- Fog: Fog or low cloud covers Middletown in 44% of 5 AM hours in December, the foggiest month. It usually thins to a third of that by 4 PM, but 15% of mid-afternoon hours are still foggy. June mornings are the least foggy (11%).
- Wind: From April through September, wind at Middletown typically builds after 2 PM. In July it peaks around 5 PM, averaging 13 mph with 8% of those hours windy, while mornings average 4 mph.
- Cloud Cover: July middays are the clearest at Middletown (2% average cloud cover), and December middays are the cloudiest (36%).
- Solar Radiation: The strongest typical sun at Middletown comes at 1 PM in June, averaging 990 W/m².
How to read the hourly heatmaps for Middletown
This heatmap shows how average temperature at Middletown 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 Middletown. 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 Middletown 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 Middletown 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 Middletown 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 Middletown
- October 2026 recap: October 2026 at Middletown averaged a high of 80°F, 8°F warmer than October 2025 (72°F).
- Rain year: The 2025-26 rain year (Oct. 1 to Sep. 30) brought 42.2 in. of rain to Middletown, 104% of the 40.7 in. normal.
Location Details
Middletown weather questions
Everything you need to know about weather and visiting Middletown
What is the weather like at Middletown today?
It's 49°F at Middletown right now, with a comfort score of 71 (very good). Today's forecast high at Middletown is 57°F, 7°F below the mid November normal of 64°F. The best window today is 2 PM to 5 PM, at about 47°F with a 3 mph wind (comfort 61).
What is the best month to visit Middletown?
By typical temperature, wind, cloud, humidity, and rain odds, the most comfortable months at Middletown are May, September, and October. The best hours are usually 10 AM to 1 PM in May, 9 AM to noon in September, and 11 AM to 2 PM in October. The warm season lasts about 3 months, from Jun 26 to Sep 23, when the average high is 86°F or warmer. Highs peak around Jul 8 at about 91°F.
What are the warmest and coldest months at Middletown?
July is the warmest month at Middletown, with an average high of 91°F. December is the coldest, with an average low of 36°F.
When does the fog burn off at Middletown?
Fog or low cloud covers Middletown in 44% of 5 AM hours in December, the foggiest month. It usually thins to a third of that by 4 PM, but 15% of mid-afternoon hours are still foggy. June mornings are the least foggy (11%).
When is it windiest at Middletown?
From April through September, wind at Middletown typically builds after 2 PM. In July it peaks around 5 PM, averaging 13 mph with 8% of those hours windy, while mornings average 4 mph.
How much rain does Middletown get?
December is the wettest month (8.6 in.), out of about 40.7 in. a year. The rainy season runs from Oct 26 to Apr 21, when a day has at least a 21% chance of measurable rain. That stretch brings 90% of the year's rain. The 2025-26 rain year (Oct. 1 to Sep. 30) brought 42.2 in. of rain to Middletown, 104% of the 40.7 in. normal.
How does Middletown weather compare with Cobb Mountain Area?
Cobb Mountain Area sits 1,690 ft higher, 8 miles away. Its summer highs average 6°F cooler and its winter lows 1°F milder than Middletown.
What kind of place is Middletown?
Middletown is a small unincorporated town in southern Lake County, set in a valley at the north foot of Mount St. Helena. Highway 29 comes down from Calistoga here, and Highway 175 heads up toward Cobb. For many Bay Area drivers it is the first stop over the mountain. The 2015 Valley Fire swept from Cobb down through town in a single day. Middletown is also home to the free Calpine Geothermal Visitor Center, which explains the steam field at The Geysers in the mountains to the west.
What is Middletown weather like in November?
November at Middletown averages a high of 64°F and a low of 40°F, with 4.0 in. of rain over about 8 rainy days. About 26% of morning hours are foggy. Afternoon wind averages 5 mph.
More about Middletown weather
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.
- Lake County News, Friday heat advisory issued for Lake County (June 9, 2022) (accessed 2026-10-27)
- Calpine, Calpine Geothermal Visitor Center (accessed 2026-10-27)
- Lake County Tourism Improvement District, Middletown Trailside Nature Preserve (accessed 2026-10-27)
- Caltrans, Winter Driving Tips (accessed 2026-10-27)
- County of Lake, Lake Co Ready (accessed 2026-10-27)
- Lake County News, More snow expected; caution urged while driving (Jan. 22, 2008) (accessed 2026-10-27)
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