Storm Station
Castro Valley, California
59°
Partly cloudy· Feels like 59°·Light breeze 4 mph W
A slight chance of drizzle. Cloudy, with a low around 56. Southwest wind around 6 mph. Chance of precipitation is 20%.
-UV
-Air quality
82%Humidity
48%Cloud

What is measuring near here

The 4 instruments nearest Castro Valley, 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 now2 instruments

HaywardHWD

At an airfield/3.9 mi away/29 ft/182 ft below here

temp, wind, gust, visibility, precip, pressure

Rank6of 3,123

measured daily2 instruments

Castro Valley 1.7 WNWCA-AL-43

In a volunteer observer's own ground/1.2 mi away/469 ft/258 ft above here

precip, snowfall, snow depth

Rank-

Oakland - Upper San LeanfroUSLC1

At a cooperative observer's station/6.9 mi away/316 ft/105 ft above here

snowfall, snow depth, precip, high, low

Rank-

Station report

The weather at Hayward, drawn

The nearest airport reporting now, 3.9 mi from Castro Valley. From its report of Sep 27, 2026, 4:54 AM local time: 3 of its 6 sheets.

The sky

Overcast at 1,600 ft; the ceiling is 1,600 ft; visibility 10 mi or more.

Section of the sky over Hayward, height above the station to scale: overcast cloud with its base at 1,600 feet, the ceiling at 1,600 feet, and visibility of 10 mi or more.1122334455667788AABBCCDDEE© 2026 STORM STATION 247THE FIELD BOOKSTATION REPORT HWDFIG. A THE SKY OVER HAYWARDSECTION, HEIGHT ABOVE THE STATION TO SCALE, EACH LAYER AT THE HEIGHT OF ITS BASE AS REPORTED; COVER IN EIGHTHS OF THE SKY; TOPS NOT MEASUREDFT ABOVE THE STATION05001,0001,5002,0002,5003,000ETAGESLOWTHE STATIONTHE CEILOMETER READS TO 12,000 FT, ABOVE THIS SHEETOVC 1,600 FTOVERCAST, 8 EIGHTHS OF THE SKYCEILING 1,600 FTVISIBILITY, MILES: 10 MI OR MORE0510TITLEHayward, the skySTATION REPORT · ASOS HWDTYPESECTIONSCALEHEIGHT TO SCALEREVAS REPORTED SHEET 1 of 6DATE2026-09-27IDSR-HWD-1DRAWN AS linework on paperSOURCES FB-SKY-001, FB-SKY-017, FB-SKY-016, FB-SKY-018

The air

59.0 F with a dew point of 53.0 F, 80 per cent relative humidity. Air lifted from the station would cool to its dew point, where cloud forms, about 1,400 ft up; the lowest cloud reported is at 1,600 ft.

Chart of the air at Hayward: temperature 59.0 degrees Fahrenheit and dew point 53.0, 80 per cent relative humidity; air lifted from the station cools along the dry rate and meets its dew point about 1,400 feet above the station, against the lowest cloud reported at 1,600 feet; height to scale.1122334455667788AABBCCDDEE© 2026 STORM STATION 247THE FIELD BOOKSTATION REPORT HWDFIG. B THE AIR AT HAYWARDTHE REPORTED TEMPERATURE AND DEW POINT, AND AIR LIFTED FROM THE STATION WITHOUT MIXING UNTIL IT SATURATES; HEIGHT ABOVE THE STATION TO SCALEFT ABOVE THE STATION01,0002,0003,00040 F50 F60 F70 FSATURATES 1,400 FT ABOVE THE STATION, AT 51.6 FLOWEST CLOUD REPORTED, OVC 1,600 FTTEMPERATURE 59.0 FDEW POINT 53.0 FSPREAD 6.0 FRELATIVE HUMIDITY 80 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 POINTTITLEHayward, the airSTATION REPORT · ASOS HWDTYPECHARTSCALEHEIGHT TO SCALEREVAS REPORTED SHEET 2 of 6DATE2026-09-27IDSR-HWD-2DRAWN AS linework on paperSOURCES FB-WAT-002, FB-ENG-011, FB-ENG-005

The wind

From the west southwest (250 degrees) at 6 mph: force 2, a light breeze on the Beaufort scale.

Plan of the wind at Hayward, north up: blowing from 250 degrees, the west 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 HWDFIG. C THE WIND AT HAYWARDPLAN, NORTH UP: THE WIND AS REPORTED, AND WHERE IT SITS ON THE BEAUFORT SCALENESWTHE STATIONFROM 250°BEAUFORT FORCELEAST WIND, MPH0CALM01LIGHT AIR12LIGHT BREEZE4NOW, 6 MPH3GENTLE BREEZE84MODERATE BREEZE135FRESH BREEZE196STRONG BREEZE257NEAR GALE328GALE399STRONG GALE4710STORM5511VIOLENT STORM6412HURRICANE FORCE73TITLEHayward, the windSTATION REPORT · ASOS HWDTYPEPLAN north upSCALENOT TO SCALEREVAS REPORTED SHEET 3 of 6DATE2026-09-27IDSR-HWD-3DRAWN AS linework on paperSOURCES FB-EVT-150, FB-ENG-008, FB-INS-002

The full report of Hayward, in 6 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 Castro Valley

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