At an airfield/3.0 mi away/52 ft/26 ft below here
temp, wind, gust, visibility, precip, pressure
Weather/California/Costa Mesa
Costa Mesa, California
City in Orange County, California* WHAT...High temperatures in the upper 80s to the mid 90s expected. * WHERE...Orange County Coastal Areas and San Diego County Coastal Areas. * WHEN...Until 8 PM PDT Saturday. * IMPACTS...Heat related illnesses increase during hot temperatures. * ADDITIONAL DETAILS...Low temperatures will be in the high 60s to low 70s.
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke.
74°
96°/73°
Clear·
Feels like 74°·Light breeze 5 mph NNE
Alert. A Heat Advisory is in force for Costa Mesa until 8 PM tomorrow. Read the alert in full, and see what it means in the Field Book.
Now. Costa Mesa is 74° and clear at 1 AM. The dew point is 44°, so the air feels dry and comfortable. Light breeze from the north-northeast at 5 mph.
Today and tonight. It warms to about 95° by 1 PM. Tonight falls to about 74° by 5 AM, under a mostly clear sky. No rain is expected for the rest of the day. The sun is strong around midday: UV index 7, high. Unprotected skin can burn in under half an hour.
The week. The warmest day ahead is tomorrow, near 91°, and the coolest Thursday, near 69°. Rain is likely Tuesday (51%) and Wednesday (69%). Rain is possible Thursday (42%).
The sky tonight. The sun sets at 6:17 PM. The Moon is a waxing crescent, 34% lit, and sets at 10:33 PM. The next full Moon is Sunday, Oct 25. After dark, look for Saturn, bright in the east-southeast. A planet shines with a steady light where the stars around it twinkle. The Orionids meteor shower is active, peaking around Oct 21: at its peak, up to about 20 meteors an hour can be seen from a dark site. The sky is forecast to stay clear: a good night to look up. The day is 11 hours 21 minutes long, 2 minutes shorter than yesterday.
0UV Low
32Air quality
34%Humidity
0%Cloud
Now
1:00 AM
74feels74
now, clear
Today
Oct 16
9673
20mph
UV 7
Sat
Oct 17
9173
13mph
UV 6
Sun
Oct 18
8668
UV 6
Mon
Oct 19
8167
UV 6
Tue
Oct 20
7364
51%
Wed
Oct 21
7061
69%
Thu
Oct 22
6959
42%
74°
96°73°
91°73°
86°68°
81°67°
73°64°
70°61°
69°59°
As of 1:00 AM in Costa Mesa, California.
Air quality
The air at Costa Mesa
Index 32, good, led by ozone. Read at 1 AM from its reporting area, Central Orange (CA), 11 miles off.
32Good
- Fine particles (PM2.5)17Good11.8 mi
- Ozone32Good31 ppb11.8 mi
- Coarse particles (PM10)17Good11.8 mi
- Nitrogen dioxide8Good9.6 ppb11 mi
- Carbon monoxide-0.3 ppm11 mi
The days ahead
Moderate each day through Today, led by coarse particles. Yesterday measured 36, good.
GoodModerate
- 36YesterdayOct 15
- 64TodayOct 16
Smoke, the next 41 hours
Little smoke near the ground through Sat 5 PM: the index from smoke stays at 11 or under.
Precipitation
What has fallen at Costa Mesa
None in the last 3 days, to Fri 12 AM. Measured by radar and rain gauges, as water.
- Last 24 hours
- 0.00in
- Last 3 days
- 0.00in
Visibility
How far you can see at Costa Mesa, the next 41 hours
Visibility stays 10 miles or more through Sat 5 PM.
F
Now, today, and the week
On the radar over Costa Mesa, CaliforniaReflectivityStorm topsRain rateRain, last 24 hoursForecast temperatureForecast rain totalEvery picture
Weather instrument stations by state
What is measuring near here
The 6 instruments nearest Costa Mesa, how far away each one is, how high it stands, and what kind of measurement it makes. The nearest is 1.2 miles away.
measured now4 instruments
Rank1of 4,465
Citizen station EW7328EW7328
In a volunteer observer's own ground/5.3 mi away/72 ft/6 ft below here
temp, humidity, wind, precip, pressure
Laguna BeachNPRC1
At a river or reservoir gauge/7.6 mi away/951 ft/873 ft above here
temp, wind, gust, humidity, pressure
I-15 : Jurupa AvenueCF174
Beside a road/34.1 mi away/908 ft/830 ft above here
temp, pavement temp, wind, visibility, precip
measured daily2 instruments
Costa Mesa 0.7 NCA-OR-64
In a volunteer observer's own ground/1.2 mi away/73 ft/5 ft below here
precip, snowfall, snow depth
Santa Ana Fire STNSTAC1
At a cooperative observer's station/6.5 mi away/125 ft/47 ft above here
snowfall, snow depth, precip, high, low
Station report
The weather at Santa Ana/Jon-Wayne, drawn
The nearest airport reporting now, 3.0 mi from Costa Mesa, California. From its report of Oct 16, 2026, 12:53 AM local time: 3 of its 6 sheets.
What the snow tracker reads here
Every instrument in this state
-
Snow on the ground
Elsewhere in California
33 places, each with its own forecast and its own instruments.
Big Bear Mountainski areaBishopcityBridgeporttownChina Peakski areaDodge Ridgeski areaDonner PassfeatureFresnocityHeavenlysurveyed ski areaHomewoodski areaJune Mountainski areaKirkwoodsurveyed ski areaLos AngelescityMammoth LakestownMammoth Mountainsurveyed ski areaMount ShastafeatureMount Shasta CitycityMount Shasta Ski Parkski areaMount WhitneyfeatureMountain Highski areaNorthstarsurveyed ski areaPalisades Tahoesurveyed ski areaReddingcitySacramentocitySan DiegocitySan FranciscocitySierra NevadafeatureSierra-at-Tahoeski areaSnow Valleyski areaSouth Lake TahoecitySugar Bowlski areaSusanvillecityTruckeetownYosemitefeature
Near Costa Mesa
The nearest places, each with its own forecast and the instruments nearest it.
- Newport Beachcity, 3 mi
- Fountain Valleycity, 4 mi
- Huntington Beachcity, 5 mi
- Santa Anacity, 6 mi
- Midway Citycommunity, 7 mi
- Irvinecity, 8 mi
- Tustincity, 8 mi
- Westminstercity, 8 mi
- Garden Grovecity, 8 mi
- North Tustincommunity, 10 mi
- Orangecity, 11 mi
- Stantoncity, 11 mi