Barometric pressure in San Jose
Taking each day as a whole, pressure has been falling steadily. Down 4 hPa since this time yesterday. The fall carries on until this afternoon.
Sea level reading, as of 08:00 local time.
The past week and the days ahead
The shaded part shows the days already gone. The thicker line is the forecast. The thin grey line is the average over a whole day, so you can see where pressure is heading under the daily up and down.
The week ahead
Each day at a glance: how far pressure moves, and the low and high it reaches.
Eases down slowly through the day.
34° / 18°low 1011 · high 1015 hPa
Rises steadily through the day.
32° / 18°low 1013 · high 1017 hPa
Dips in the afternoon, and comes back by the end of the day.
31° / 16°low 1015 · high 1018 hPa
Eases down slowly through the day.
32° / 18°low 1015 · high 1017 hPa
Barely moves all day.
32° / 19°low 1015 · high 1017 hPa
Still barely moving.
30° / 18°low 1015 · high 1017 hPa
Still barely moving.
28° / 16°low 1015 · high 1017 hPa
Hour by hour
| Hour | Weather and temperature | Rain (mm) | Pressure (hPa) |
|---|---|---|---|
| 00:00 |  20° | 1015 | |
| 01:00 | 20° | 1015 | |
| 02:00 | 19° | 1015 | |
| 03:00 | 19° | 1014 | |
| 04:00 | 18° | 1014 | |
| 05:00 | 18° | 1014 | |
| 06:00 | 18° | 1014 | |
| 07:00 | 18° | 1014 | |
| 08:00 | 20° | 1014 | |
| 09:00 | 22° | 1014 | |
| 10:00 | 25° | 1014 | |
| 11:00 | 28° | 1014 | |
| 12:00 | 31° | 1014 | |
| 13:00 | 33° | 1013 | |
| 14:00 | 34° | 1013 | |
| 15:00 | 34° | 1012 | |
| 16:00 | 34° | 1012 | |
| 17:00 | 33° | 1011 | |
| 18:00 | 31° | 1012 | |
| 19:00 | 28° | 1012 | |
| 20:00 | 25° | 1012 | |
| 21:00 | 24° | 1013 | |
| 22:00 | 23° | 1013 | |
| 23:00 | 22° | 1013 |
Biggest change: Monday, up 4 hPa.
Pressure bottoms out near 1011 hPa this afternoon, and rises after that.
In San Jose pressure moves on a daily clock: about 2 hPa between its regular low and high, at much the same hours every day. That daily swing is most of the shape you see on the graph, so the change since yesterday tells you more here than the change over the past few hours.
San Jose sits 26 m above sea level, so a barometer in the city reads about 3 hPa lower than the sea-level figure. A home station set to the local reading should show about 1011 hPa as of 08:00.
The hours already past are the model's record of each hour as it passed, anchored to real observations, though not a reading from an instrument in San Jose.
About San Jose
In the San Francisco Bay Area, San Jose sees few big pressure changes. Sudden daily changes occur about seven times a year, mostly in winter and early spring. The rest of the calendar passes in long, even stretches, sometimes more than a week without meaningful movement. The average pressure glides from a January high near 1020 hPa to a September low around 1013, then back. That is a gentle annual rise and fall, not a weather story. Even so, the readings run on the high side: about 81 days a year come in above 1020 hPa.
Sources: WikipediaERA5 reanalysisElevation: Copernicus DEM via Open-Meteo
Cities nearby
Open one to see its pressure, or search for your own city at the top of the page.
Curious what you are breathing? See the air quality in San Jose today, on our sister site 
airindex.today.
Common questions
What is a normal barometric pressure?
Near 1013 hPa at sea level; the exact standard figure, 1013.25 hPa, is the same as 760 mmHg, 29.92 inHg or 101.3 kPa. Anything between roughly 1000 and 1025 hPa is ordinary. Which way it is going matters far more than the number itself.
Why does my own barometer show a different number?
Usually altitude, and sometimes the instrument itself. Weather services correct readings to what they would be at sea level, so that cities can be compared. The figure for San Jose, which stands 26 m above sea level, is in the note above: about 3 hPa below the sea-level reading. If your barometer is already set to sea level and still reads slightly differently, that is the setting on the instrument rather than the weather.
Is a millibar the same as a hectopascal?
Yes. One millibar and one hectopascal are exactly the same amount of pressure, so 1013 mbar and 1013 hPa mean the same thing. The name changed; the number did not.
Does falling pressure mean rain?
Not by itself. Away from the tropics, falling pressure usually means a low is approaching, and lows carry the fronts that bring cloud and rain, so the two often arrive together. But a shallow fall can pass with nothing more than cloud, and rain falls under steady pressure too. The graph tells you a system is on the way, not how wet it will be. The week ahead, just above, shows the rain forecast beside the pressure.
