barometer.today

Barometric pressure in Zanzibar

1017hPa
Steady

Taking each day as a whole, pressure has barely moved. It stays close to where it is now through the week ahead.

Sea level reading, as of 18:00 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.

now27° / 24°27° / 24°27° / 23°28° / 23°27° / 23°26° / 24°27° / 24°27° / 24°27° / 24°28° / 24°27° / 24°27° / 25°28° / 24°Mon 17Tue 18Wed 19Thu 20Fri 21Sat 22Sun 23Mon 24Tue 25Wed 26Thu 27Fri 28Sat 2910141016101810201022
The forecast runs 7 days ahead.

The week ahead

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

TodayAug 23 +1 hPa

Climbs in the morning, then settles back.

Light drizzle27° / 24°2.1 mm

low 1017 · high 1020 hPa

MonAug 24 0 hPa

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

Light drizzle27° / 24°0.6 mm

low 1017 · high 1020 hPa

TueAug 25 −1 hPa

The same daily dip.

Light drizzle27° / 24°1.2 mm

low 1016 · high 1020 hPa

WedAug 26 0 hPa

Climbs in the morning, then settles back.

Clear sky28° / 24°

low 1016 · high 1020 hPa

ThuAug 27 +1 hPa

Edges up slowly through the day.

Light drizzle27° / 24°

low 1016 · high 1021 hPa

FriAug 28 0 hPa

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

Light drizzle27° / 25°2.1 mm

low 1016 · high 1021 hPa

SatAug 29 0 hPa

Dips overnight, and comes back by the end of the day.

Light drizzle28° / 24°2.0 mm

low 1016 · high 1021 hPa

Hour by hour
Today Aug 23
HourWeather and temperatureRain (mm)Pressure (hPa)
00:00Clear sky25°1018
01:00Clear sky25°1018
02:00Clear sky24°1017
03:00Mainly clear24°1017
04:00Light drizzle24°0.21017
05:00Light drizzle24°0.21017
06:00Light drizzle24°0.21018
07:00Light drizzle24°0.21018
08:00Light drizzle25°0.21020
09:00Light drizzle25°0.21020
10:00Light drizzle25°0.21020
11:00Light drizzle26°0.21020
12:00Light drizzle26°0.21019
13:00Light drizzle26°0.11018
14:00Light drizzle27°0.11018
15:00Light drizzle27°0.11017
16:00Clear sky27°1017
17:00Clear sky26°1017
18:00Clear sky26°1017
19:00Clear sky26°1017
20:00Clear sky25°1018
21:00Clear sky25°1018
22:00Clear sky25°1019
23:00Mainly clear25°1019

A quiet week, with no day moving more than 4 hPa.

What happens next

The forecast shows no big move in either direction this week.

The daily rhythm

Zanzibar has a strong daily rhythm: pressure swings about 4 hPa between a regular low and high, at almost the same hours each day. Most of what the graph shows is that daily wave, which is why the change since yesterday says more here than the change over a few hours.

Your own barometer

Zanzibar is at sea level, so a barometer there reads about the same as the sea-level figure.

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 Zanzibar.

Cities nearby

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

Watching the sun as well? See how strong the UV is in Zanzibar right now, 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. Weather services correct readings to what they would be at sea level, so that cities can be compared. Zanzibar is at sea level, so there is almost nothing to correct and the two figures agree.

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.