Barometric pressure in Tri-Cities today
Falling
Beyond the daily ups and downs, pressure has eased down over the past day. It is 3 hPa lower than this time yesterday. Looking ahead, it holds near this level until this morning, then falls sharply until tonight. After that it moves between 1017 and 1022 hPa until Sunday morning, then falls sharply until Monday afternoon, then goes up and down between 1010 and 1019 hPa for the rest of the week.
Current sea-level reading for Tri-Cities, as of 05:00 local time.
Pressure graph: the past week and the week ahead
The shaded part shows the days already gone. The thicker line is the forecast.
Tri-Cities sits 111 m above sea level, so a barometer in the city reads about 14 hPa lower than the sea-level figure. A home station set to the local reading should show about 1015 hPa as of 05:00.
The week ahead: the pressure forecast day by day
Each day at a glance: which way pressure moves, and how far.
21° / 7°Holds near 1029 until morning, then drops sharply to 1018 by the end of the day.Show hourly graph23° / 12°Moves between 1017 and 1022 hPa as the overall level creeps up, ending clearly higher.Show hourly graph18° / 7°Holds near 1021 until morning, then drops sharply to 1013 by the end of the day.Show hourly graph15° / 9°Eases down to 1010 by the afternoon, and holds there.Show hourly graph19° / 6°Holds near 1011 through the night, then rises steadily to 1016 by morning, and holds there.Show hourly graph
20° / 8°Falls quickly to 1012 by the afternoon, and holds there.Show hourly graph20° / 9°Holds near 1013 until the afternoon, then climbs sharply to 1019 by the end of the day.Show hourly graphThe day that changes most: today, down 11 hPa.
Hour by hour
| Hour | Weather and temperature | Rain (mm) | Pressure (hPa) |
|---|---|---|---|
| 00:00 |  12° | 1029 | |
| 01:00 | 11° | 1029 | |
| 02:00 | 10° | 1029 | |
| 03:00 |  10° | 1029 | |
| 04:00 | 9° | 1029 | |
| 05:00 | 8° | 1029 | |
| 06:00 | 8° | 1029 | |
| 07:00 | 7° | 1029 | |
| 08:00 | 7° | 1029 | |
| 09:00 | 9° | 1029 | |
| 10:00 | 12° | 1028 | |
| 11:00 | 14° | 1028 | |
| 12:00 | 16° | 1027 | |
| 13:00 | 18° | 1025 | |
| 14:00 | 20° | 1024 | |
| 15:00 | 20° | 1023 | |
| 16:00 | 21° | 1022 | |
| 17:00 | 20° | 1021 | |
| 18:00 | 19° | 1020 | |
| 19:00 | 18° | 1020 | |
| 20:00 | 16° | 1019 | |
| 21:00 | 15° | 1019 | |
| 22:00 | 15° | 1018 | |
| 23:00 | 14° | 1018 |
How much the pressure changes in Tri-Cities
In Tri-Cities the pressure changes most from November to January. In a typical October it changes by about 4 hPa from one day to the next, and on about 2 days it rises or falls by more than 10 hPa.
When the pressure changes most
| Month | More than 5 hPa | More than 10 hPa |
|---|---|---|
| January | 14 | 4 |
| February | 11 | 3 |
| March | 13 | 3 |
| April | 11 | 2 |
| May | 8 | 1 |
| June | 6 | 0 |
| July | 3 | 0 |
| August | 4 | 0 |
| September | 6 | 0 |
| October | 11 | 2 |
| November | 14 | 4 |
| December | 15 | 5 |
A typical day’s change through the year
Each date of the year has its own bar. The taller the bar, the bigger a typical day’s change around that date.
Does the pressure change a lot in Tri-Cities?
Tri-Cities has more days with a change of more than 10 hPa than 85 out of every 100 large cities.
Each dot stands for up to 20 cities with 100,000 people or more. The first column is much taller than shown. Cities higher than 1,000 m are left out, and so are smaller cities within 15 km of a bigger one, unless they are capitals, so that suburbs are not counted twice.
These figures come from ERA5, in which the European weather centre ECMWF rebuilds past weather from a weather model and observations, for an area about 28 km across around Tri-Cities, 1991 to 2020. Each change is the difference between one day’s average pressure and the next day’s.
Cities nearby
Open one to see its pressure, or search for your own city at the top of the page.
More about air pressure
What we have written about how pressure behaves and how it is measured.
Where air pressure changes the most, city by city
Thirty years of data, ranked by city: where air pressure swings most from day to day and where it hardly moves. London, New York, Tokyo and 128 more.
How much does air pressure change in a day?
A normal day moves the barometer about 4 hPa in London and half of one in Singapore. What counts as a big drop, and how often one comes.
Why barometric pressure deserved its own site
Air pressure is the weather number people ask about most and understand least: is it high, is it rising or falling, does it matter today.
Is this weather normal for the season? See how these days compare with Tri-Cities weather since 1940, on our sister site 
weatherjourney.com.
Questions about the pressure in Tri-Cities
What is the barometer reading in Tri-Cities right now?
Sea-level pressure in Tri-Cities is 1029 hPa as of 05:00 local time, unchanged over the last three hours. A barometer in the city itself, 111 m up, shows about 1015 hPa.
Is the barometer rising or falling in Tri-Cities today?
Beyond the daily ups and downs, pressure has eased down over the past day. It is 3 hPa lower than this time yesterday. Over the last three hours it has not changed.
Has the pressure in Tri-Cities changed since yesterday?
Yes. At this time yesterday it read 1032 hPa; it is 3 hPa lower now.
What has the pressure in Tri-Cities been over the last few days?
Over the past 7 days it ran between 1004 hPa (a week ago, in the afternoon) and 1035 hPa (yesterday morning). The biggest change in any 24 hours was a rise of 10 hPa, in the 24 hours ending yesterday morning.
Is 1029 hPa high or low pressure?
Atmospheric pressure between about 1000 and 1025 hPa is ordinary at sea level. 1029 hPa is above that range: high pressure. In Tri-Cities most days average between 1005 and 1030 hPa. The last 24 hours average about 1031 hPa, higher than the city usually sees.
What is normal barometric pressure for Tri-Cities?
From 1991 to 2020 the sea-level average for Tri-Cities was 1016 hPa, and most days average between 1005 and 1030 hPa. It is usually highest in December and January and lowest from June to August.
When does barometric pressure change the most in Tri-Cities?
The pressure in Tri-Cities changes most from November to January. Between 1991 and 2020, Tri-Cities had about 25 days a year with a big change, of more than 10 hPa from one day to the next.
Why does my own barometer show a different number?
Usually altitude, and sometimes the instrument itself. To compare cities, pressure is corrected to sea level. The figure for Tri-Cities, which stands 111 m above sea level, is in the note above: about 14 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.
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.
