barometer.today

Barometric pressure in Bairro da Penha

1015hPa
Falling

Taking each day as a whole, pressure has been falling steadily. It is 3 hPa lower than this time yesterday. It continues to fall until Saturday afternoon.

Sea level reading, as of 23:00 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 dotted line is the average over a whole day, so you can see where pressure is heading under the daily up and down.

now26° / 13°22° / 11°23° / 13°19° / 12°19° / 14°24° / 15°25° / 15°29° / 14°33° / 17°31° / 18°33° / 16°22° / 16°21° / 13°Fri 21Sat 22Sun 23Mon 24Tue 25Wed 26Thu 27Fri 28Sat 29Sun 30Mon 31Tue 1Wed 210051010101510201025
The forecast runs 6 days ahead.

The week ahead

Each day at a glance: how far pressure moves, and the low and high it reaches.

TodayAug 27 −3 hPa

Falls steadily through the day.

Light drizzle25° / 15°4.0 mm

low 1013 · high 1019 hPa

FriAug 28 −1 hPa

Eases down slowly through the day.

Overcast29° / 14°

low 1010 · high 1016 hPa

SatAug 29 −1 hPa

Dips in the afternoon, and comes back by the end of the day.

Mainly clear33° / 17°

low 1010 · high 1014 hPa

SunAug 30 +1 hPa

Edges up slowly through the day.

Drizzle31° / 18°1.5 mm

low 1013 · high 1016 hPa

MonAug 31 −5 hPa

Falls quickly, most of it in the morning.

Partly cloudy33° / 16°

low 1007 · high 1014 hPa

TueSep 1 +7 hPa

Rises quickly, most of it in the evening.

Light rain22° / 16°16.4 mm

low 1007 · high 1016 hPa

WedSep 2 +4 hPa

Rises steadily through the day.

Light drizzle21° / 13°2.8 mm

low 1017 · high 1021 hPa

Hour by hour
Today Aug 27
HourWeather and temperatureRain (mm)Pressure (hPa)
00:00Light drizzle17°0.11018
01:00Light drizzle17°0.21018
02:00Light drizzle16°0.21017
03:00Light drizzle16°0.21017
04:00Dense drizzle16°1.01017
05:00Dense drizzle15°1.01017
06:00Dense drizzle15°1.01017
07:00Overcast16°1018
08:00Overcast17°1019
09:00Partly cloudy19°1019
10:00Light drizzle20°0.11019
11:00Light drizzle22°0.11018
12:00Light drizzle23°0.11017
13:00Clear sky24°1016
14:00Clear sky25°1014
15:00Clear sky25°1013
16:00Clear sky24°1013
17:00Clear sky22°1013
18:00Clear sky20°1013
19:00Clear sky19°1014
20:00Clear sky18°1015
21:00Clear sky17°1015
22:00Clear sky16°1015
23:00Clear sky15°1015

Of the seven days, Tuesday moves most: up 7 hPa.

What happens next

The low point comes on Saturday afternoon, near 1010 hPa; after that it rises.

The daily rhythm

In Bairro da Penha pressure moves on a daily clock: about 4 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.

Your own barometer

Bairro da Penha sits 772 m above sea level, so a barometer in the city reads about 88 hPa lower than the sea-level figure. A home station set to the local reading should show about 927 hPa as of 23:00.

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 Bairro da Penha.

Cities nearby

Open one to see its pressure, or search for your own city at the top of the page.

Out in the sun today? Check the UV level in Bairro da Penha, on our sister site uvi.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 Bairro da Penha, which stands 772 m above sea level, is in the note above: about 88 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.