Storm Station
Altadena, California
72° 83°/64°
Overcast· Feels like 72°·Light air 3 mph ESE
Mostly cloudy, with a low around 65. East southeast wind 5 to 10 mph.
0UV Low
75Air quality
48%Humidity
100%Cloud
Now
12:30 AM
72feels72
now, overcast
Today
Sep 27
8364
UV 7
drizzle light
Mon
Sep 28
8158
UV 7
mostly clear day
Tue
Sep 29
8569
UV 7
clear day
Wed
Sep 30
8468
UV 7
clear day
Thu
Oct 1
9173
UV 7
clear day
Fri
Oct 2
9779
UV 7
clear day
Sat
Oct 3
9783
UV 7
clear day
72°
83°64°
81°58°
85°69°
84°68°
91°73°
97°79°
97°83°

As of 12:30 AM in Altadena, California.

What is measuring near here

The 4 instruments nearest Altadena, how far away each one is, how high it stands, and what kind of measurement it makes. The nearest is 0.5 miles away.

measured now2 instruments

Henninger FlatsHNGC1

At a river or reservoir gauge/2.6 mi away/2,858 ft/1,571 ft above here

temp, wind, gust, humidity, pressure

Rank595of 3,115

Mount WilsonMWS

At an airfield/5.1 mi away/5,705 ft/4,418 ft above here

temp, wind, gust, visibility, precip, pressure

Rank682of 3,115

measured daily2 instruments

AltadenaADAC1

At a cooperative observer's station/0.5 mi away/1,145 ft/142 ft below here

snowfall, snow depth, precip, high, low

Rank-

Altadena 1.0 WCA-LA-127

In a volunteer observer's own ground/0.9 mi away/1,204 ft/83 ft below here

precip, snowfall, snow depth

Rank-

Station report

The weather at Mount Wilson, drawn

The nearest airport reporting now, 5.1 mi from Altadena. From its report of Sep 27, 2026, 12:20 AM local time: 3 of its 5 sheets.

The air

60.8 F with a dew point of 44.6 F, 55 per cent relative humidity. Air lifted from the station would cool to its dew point, where cloud forms, about 3,700 ft up.

Chart of the air at Mount Wilson: temperature 60.8 degrees Fahrenheit and dew point 44.6, 55 per cent relative humidity; air lifted from the station cools along the dry rate and meets its dew point about 3,700 feet above the station; height to scale.1122334455667788AABBCCDDEE© 2026 STORM STATION 247THE FIELD BOOKSTATION REPORT MWSFIG. B THE AIR AT MOUNT WILSONTHE REPORTED TEMPERATURE AND DEW POINT, AND AIR LIFTED FROM THE STATION WITHOUT MIXING UNTIL IT SATURATES; HEIGHT ABOVE THE STATION TO SCALEFT ABOVE THE STATION01,0002,0003,0004,0005,00030 F40 F50 F60 F70 FSATURATES 3,700 FT ABOVE THE STATION, AT 41.0 FTEMPERATURE 60.8 FDEW POINT 44.6 FSPREAD 16.2 FRELATIVE HUMIDITY 55 PER CENTTHE AIR COOLS ABOUT 5.4 F EACH 1,000 FT IT RISES, AND ITS DEW POINT ABOUT 1 FSOLID: THE LIFTED AIR'S TEMPERATURE; DASHED: ITS DEW POINTTITLEMount Wilson, the airSTATION REPORT · ASOS MWSTYPECHARTSCALEHEIGHT TO SCALEREVAS REPORTED SHEET 1 of 5DATE2026-09-27IDSR-MWS-1DRAWN AS linework on paperSOURCES FB-WAT-002, FB-ENG-011, FB-ENG-005

The wind

From the southwest (220 degrees) at 6 mph: force 2, a light breeze on the Beaufort scale.

Plan of the wind at Mount Wilson, north up: blowing from 220 degrees, the southwest, at 6 miles an hour; beside it the Beaufort scale from calm to hurricane force, force 2, light breeze, marked.1122334455667788AABBCCDDEE© 2026 STORM STATION 247THE FIELD BOOKSTATION REPORT MWSFIG. C THE WIND AT MOUNT WILSONPLAN, NORTH UP: THE WIND AS REPORTED, AND WHERE IT SITS ON THE BEAUFORT SCALENESWTHE STATIONFROM 220°BEAUFORT FORCELEAST WIND, MPH0CALM01LIGHT AIR12LIGHT BREEZE4NOW, 6 MPH3GENTLE BREEZE84MODERATE BREEZE135FRESH BREEZE196STRONG BREEZE257NEAR GALE328GALE399STRONG GALE4710STORM5511VIOLENT STORM6412HURRICANE FORCE73TITLEMount Wilson, the windSTATION REPORT · ASOS MWSTYPEPLAN north upSCALENOT TO SCALEREVAS REPORTED SHEET 2 of 5DATE2026-09-27IDSR-MWS-2DRAWN AS linework on paperSOURCES FB-EVT-150, FB-ENG-008, FB-INS-002

The column

At 5,705 ft above sea level, 19 per cent of the atmosphere's air lies below the station. The standard atmosphere puts the pressure there at 24.25 inHg and the temperature at 38.7 F; it reports 60.8 F, 22.1 F warmer than standard.

Section from sea level of where Mount Wilson stands in the atmosphere, height to scale: the station 5,705 feet above sea level with 19 per cent of the air below it; the standard atmosphere's pressure there, 24.25 inches of mercury, and temperature, 38.7 degrees Fahrenheit.1122334455667788AABBCCDDEE© 2026 STORM STATION 247THE FIELD BOOKSTATION REPORT MWSFIG. D WHERE MOUNT WILSON STANDS IN THE ATMOSPHERESECTION FROM SEA LEVEL, HEIGHT TO SCALE, THE STATION IN THE STANDARD ATMOSPHEREFT ABOVE SEA LEVEL05,00010,00015,000SEA LEVEL, 29.92 inHg IN THE STANDARD ATMOSPHEREMOUNT WILSON19 PER CENT OF THE AIR BELOW IT5,705 FT10 PER CENT OF THE AIR BELOW, 2,890 FT20 PER CENT OF THE AIR BELOW, 6,050 FT30 PER CENT OF THE AIR BELOW, 9,540 FT40 PER CENT OF THE AIR BELOW, 13,470 FTSTANDARD PRESSURE HERE24.25 inHgSTANDARD TEMPERATURE HERE38.7 FTEMPERATURE, REPORTED60.8 FTITLEMount Wilson, the columnSTATION REPORT · ASOS MWSTYPESECTIONSCALEHEIGHT TO SCALEREVAS REPORTED SHEET 3 of 5DATE2026-09-27IDSR-MWS-3DRAWN AS linework on paperSOURCES FB-ENG-001, FB-ENG-003

The full report of Mount Wilson, in 5 sheets, each beside the Field Book plates that explain it

-in

Snow on the ground

Elsewhere in California

33 places, each with its own forecast and its own instruments.

Near Altadena

The nearest places, each with its own forecast and the instruments nearest it.