Fast Forecast

WEATHER FOR BUSINESS

We supply weather data to businesses

Free Weather Plugin

Add this forecast to your website



Local Weather

Fal 14 Day Long Range Forecast

14 Day weather providing an extended long range forecast outlook for Fal

Cornwall, United Kingdom

Long range weather outlook for Fal includes 14 day forecast summary:

Reviewing the forecast for Fal Over the next 14 days and the average daytime maximum temperature will be around 17°C, with a high for the two weeks of 19°C expected on the afternoon of Sunday 19th. The mean minimum temperature will be 10°C, dipping to its lowest on the morning of Thursday 23rd at 8°C. The next 14 days will have some days seeing a little precipitation and some days with rain. It looks like Thursday 23rd will have the most precipitation with an accumulation of around 6.0mm. On the whole winds are likely to be moderate.

DayLocal TimeDirSpeed/
Gust		Temp/
Feels Like		HumidityCloud AmountPrecip AmountWeather
Fri 17
May		06:00

E
E

 3 / 6 mph 54 / 54°F 89%
Low level cloud: 12%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: medium
100%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
09:00

ESE
ESE

 8 / 9 mph 60 / 57°F 81%
Low level cloud: 7%
Mid level cloud: 30%
High level cloud: 100%
Most Significant Cloud Type: medium
54%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
12:00

ESE
ESE

 10 / 11 mph 63 / 61°F 78%
Low level cloud: 27%
Mid level cloud: 12%
High level cloud: 0%
Most Significant Cloud Type: low
30%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
15:00

E
E

 7 / 9 mph 63 / 61°F 82%
Low level cloud: 33%
Mid level cloud: 7%
High level cloud: 93%
Most Significant Cloud Type: low
46%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
18:00

E
E

 4 / 5 mph 62 / 59°F 86%
Low level cloud: 31%
Mid level cloud: 58%
High level cloud: 100%
Most Significant Cloud Type: low
63%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
21:00

N
N

 3 / 6 mph 53 / 53°F 92%
Low level cloud: 12%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: medium
100%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Sat 18
May		00:00

N
N

 3 / 6 mph 51 / 51°F 93%
Low level cloud: 8%
Mid level cloud: 45%
High level cloud: 16%
Most Significant Cloud Type: medium
68%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
03:00

NNW
NNW

 5 / 11 mph 50 / 49°F 92%
Low level cloud: 3%
Mid level cloud: 21%
High level cloud: 96%
Most Significant Cloud Type: medium
34%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
06:00

NNW
NNW

 6 / 11 mph 55 / 52°F 95%
Low level cloud: 20%
Mid level cloud: 3%
High level cloud: 20%
Most Significant Cloud Type: low
23%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
09:00

NNW
NNW

 9 / 11 mph 63 / 60°F 83%
Low level cloud: 1%
Mid level cloud: 46%
High level cloud: 94%
Most Significant Cloud Type: medium
53%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
12:00

NNW
NNW

 9 / 10 mph 65 / 63°F 82%
Low level cloud: 16%
Mid level cloud: 25%
High level cloud: 32%
Most Significant Cloud Type: low
28%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
15:00

N
N

 8 / 12 mph 65 / 62°F 85%
Low level cloud: 40%
Mid level cloud: 46%
High level cloud: 7%
Most Significant Cloud Type: low
56%
Expect 0.1 In of precipitation over the past 3 hours.
0.1 In
18:00

N
N

 9 / 12 mph 63 / 60°F 91%
Low level cloud: 37%
Mid level cloud: 45%
High level cloud: 32%
Most Significant Cloud Type: low
56%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
21:00

N
N

 6 / 14 mph 55 / 52°F 94%
Low level cloud: 6%
Mid level cloud: 26%
High level cloud: 2%
Most Significant Cloud Type: medium
42%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Sun 19
May		00:00

NNE
NNE

 5 / 11 mph 53 / 51°F 92%
Low level cloud: 7%
Mid level cloud: 20%
High level cloud: 0%
Most Significant Cloud Type: low
14%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
03:00

NNE
NNE

 5 / 11 mph 52 / 51°F 92%
Low level cloud: 35%
Mid level cloud: 24%
High level cloud: 0%
Most Significant Cloud Type: low
43%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
06:00

NE
NE

 5 / 9 mph 57 / 54°F 92%
Low level cloud: 6%
Mid level cloud: 28%
High level cloud: 0%
Most Significant Cloud Type: medium
44%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
09:00

E
E

 8 / 10 mph 63 / 61°F 80%
Low level cloud: 10%
Mid level cloud: 0%
High level cloud: 1%
Most Significant Cloud Type: low
9%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
12:00

E
E

 6 / 8 mph 66 / 64°F 73%
Low level cloud: 5%
Mid level cloud: 0%
High level cloud: 14%
Most Significant Cloud Type: low
6%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
15:00

ESE
ESE

 6 / 6 mph 66 / 64°F 73%
Low level cloud: 23%
Mid level cloud: 2%
High level cloud: 13%
Most Significant Cloud Type: low
25%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
18:00

SSE
SSE

 1 / 1 mph 63 / 62°F 78%
Low level cloud: 93%
Mid level cloud: 9%
High level cloud: 0%
Most Significant Cloud Type: low
96%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
21:00

N
N

 5 / 11 mph 57 / 55°F 87%
Low level cloud: 13%
Mid level cloud: 18%
High level cloud: 0%
Most Significant Cloud Type: low
19%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Mon 20
May		00:00

NE
NE

 7 / 15 mph 52 / 49°F 89%
Low level cloud: 0%
Mid level cloud: 19%
High level cloud: 0%
Most Significant Cloud Type: medium
18%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
03:00

ENE
ENE

 7 / 15 mph 51 / 48°F 92%
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
06:00

NE
NE

 7 / 14 mph 51 / 47°F 85%
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
09:00

E
E

 8 / 9 mph 60 / 58°F 75%
Low level cloud: 0%
Mid level cloud: 4%
High level cloud: 0%
Most Significant Cloud Type: medium
4%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
12:00

ESE
ESE

 6 / 7 mph 64 / 61°F 80%
Low level cloud: 47%
Mid level cloud: 9%
High level cloud: 0%
Most Significant Cloud Type: low
50%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
15:00

SSE
SSE

 2 / 2 mph 64 / 61°F 82%
Low level cloud: 37%
Mid level cloud: 8%
High level cloud: 0%
Most Significant Cloud Type: low
39%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
18:00

NW
NW

 6 / 7 mph 63 / 60°F 85%
Low level cloud: 20%
Mid level cloud: 8%
High level cloud: 0%
Most Significant Cloud Type: low
23%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
21:00

NNW
NNW

 7 / 14 mph 54 / 50°F 94%
Low level cloud: 9%
Mid level cloud: 23%
High level cloud: 0%
Most Significant Cloud Type: low
16%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Tue 21
May		00:00

NNE
NNE

 6 / 13 mph 51 / 49°F 92%
Low level cloud: 11%
Mid level cloud: 44%
High level cloud: 0%
Most Significant Cloud Type: medium
75%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
03:00

NNE
NNE

 4 / 9 mph 50 / 49°F 89%
Low level cloud: 12%
Mid level cloud: 45%
High level cloud: 6%
Most Significant Cloud Type: medium
77%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
06:00

NNW
NNW

 4 / 6 mph 55 / 53°F 90%
Low level cloud: 57%
Mid level cloud: 46%
High level cloud: 3%
Most Significant Cloud Type: low
73%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
09:00

NNW
NNW

 5 / 6 mph 58 / 58°F 89%
Low level cloud: 92%
Mid level cloud: 44%
High level cloud: 0%
Most Significant Cloud Type: low
100%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
12:00

NW
NW

 9 / 12 mph 64 / 61°F 79%
Low level cloud: 36%
Mid level cloud: 45%
High level cloud: 0%
Most Significant Cloud Type: low
52%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
15:00

NNW
NNW

 11 / 13 mph 62 / 61°F 77%
Low level cloud: 25%
Mid level cloud: 26%
High level cloud: 2%
Most Significant Cloud Type: low
34%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
18:00

NW
NW

 11 / 12 mph 60 / 56°F 85%
Low level cloud: 41%
Mid level cloud: 33%
High level cloud: 7%
Most Significant Cloud Type: low
53%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
21:00

NW
NW

 7 / 13 mph 54 / 50°F 95%
Low level cloud: 19%
Mid level cloud: 46%
High level cloud: 13%
Most Significant Cloud Type: low
37%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Wed 22
May		00:00

WNW
WNW

 7 / 14 mph 51 / 49°F 93%
Low level cloud: 5%
Mid level cloud: 42%
High level cloud: 12%
Most Significant Cloud Type: medium
56%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
03:00

WNW
WNW

 7 / 14 mph 51 / 48°F 95%
Low level cloud: 28%
Mid level cloud: 18%
High level cloud: 12%
Most Significant Cloud Type: low
35%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
06:00

W
W

 8 / 12 mph 55 / 51°F 94%
Low level cloud: 24%
Mid level cloud: 8%
High level cloud: 9%
Most Significant Cloud Type: low
27%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
09:00

WNW
WNW

 12 / 14 mph 61 / 59°F 79%
Low level cloud: 42%
Mid level cloud: 42%
High level cloud: 18%
Most Significant Cloud Type: low
58%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
12:00

W
W

 15 / 17 mph 59 / 56°F 77%
Low level cloud: 62%
Mid level cloud: 28%
High level cloud: 12%
Most Significant Cloud Type: low
73%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
15:00

W
W

 15 / 17 mph 60 / 56°F 73%
Low level cloud: 38%
Mid level cloud: 11%
High level cloud: 9%
Most Significant Cloud Type: low
43%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
18:00

WNW
WNW

 19 / 22 mph 55 / 49°F 86%
Low level cloud: 65%
Mid level cloud: 12%
High level cloud: 13%
Most Significant Cloud Type: low
70%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
21:00

NW
NW

 16 / 24 mph 51 / 45°F 87%
Low level cloud: 79%
Mid level cloud: 32%
High level cloud: 0%
Most Significant Cloud Type: low
90%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Thu 23
May		00:00

NW
NW

 15 / 25 mph 50 / 44°F 85%
Low level cloud: 71%
Mid level cloud: 44%
High level cloud: 0%
Most Significant Cloud Type: low
86%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
03:00

WNW
WNW

 9 / 16 mph 48 / 44°F 93%
Low level cloud: 47%
Mid level cloud: 16%
High level cloud: 0%
Most Significant Cloud Type: low
52%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
06:00

NNW
NNW

 17 / 35 mph 47 / 40°F 90%
Low level cloud: 70%
Mid level cloud: 25%
High level cloud: 0%
Most Significant Cloud Type: low
78%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
09:00

NNW
NNW

 17 / 27 mph 50 / 44°F 94%
Low level cloud: 91%
Mid level cloud: 64%
High level cloud: 0%
Most Significant Cloud Type: low
100%
Expect 0.1 In of precipitation over the past 3 hours.
0.1 In
12:00

NNW
NNW

 17 / 23 mph 54 / 49°F 90%
Low level cloud: 91%
Mid level cloud: 18%
High level cloud: 0%
Most Significant Cloud Type: low
97%
Expect 0.1 In of precipitation over the past 3 hours.
0.1 In
15:00

NNW
NNW

 17 / 21 mph 56 / 51°F 89%
Low level cloud: 85%
Mid level cloud: 14%
High level cloud: 0%
Most Significant Cloud Type: low
89%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
18:00

NNW
NNW

 16 / 22 mph 54 / 49°F 86%
Low level cloud: 83%
Mid level cloud: 27%
High level cloud: 0%
Most Significant Cloud Type: low
92%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
21:00

NW
NW

 14 / 24 mph 52 / 46°F 89%
Low level cloud: 11%
Mid level cloud: 32%
High level cloud: 0%
Most Significant Cloud Type: medium
62%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
DayLocal TimeDirSpeed/
Gust		Temp/
Feels Like		HumidityCloud AmountPrecip AmountWeather
Fri 24
May		00:00

NNW
NNW

 14 / 30 mph 53 / 48°F 93%
Low level cloud: 47%
Mid level cloud: 2%
High level cloud: 12%
Most Significant Cloud Type: low
49%
0.0 In
06:00

N
N

 10 / 20 mph 52 / 48°F 92%
Low level cloud: 80%
Mid level cloud: 61%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.0 In
12:00

ESE
ESE

 18 / 38 mph 59 / 60°F 83%
Low level cloud: 20%
Mid level cloud: 12%
High level cloud: 5%
Most Significant Cloud Type: low
24%
0.0 In
18:00

E
E

 17 / 36 mph 59 / 55°F 92%
Low level cloud: 83%
Mid level cloud: 46%
High level cloud: 5%
Most Significant Cloud Type: low
99%
0.0 In
Sat 25
May		00:00

NNW
NNW

 13 / 27 mph 57 / 54°F 93%
Low level cloud: 65%
Mid level cloud: 45%
High level cloud: 0%
Most Significant Cloud Type: low
80%
0.0 In
06:00

SW
SW

 4 / 8 mph 54 / 53°F 92%
Low level cloud: 58%
Mid level cloud: 27%
High level cloud: 2%
Most Significant Cloud Type: low
68%
0.0 In
12:00

ESE
ESE

 8 / 16 mph 61 / 61°F 81%
Low level cloud: 80%
Mid level cloud: 24%
High level cloud: 1%
Most Significant Cloud Type: low
88%
0.0 In
18:00

WSW
WSW

 10 / 21 mph 60 / 60°F 91%
Low level cloud: 99%
Mid level cloud: 21%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.0 In
Sun 26
May		00:00

ESE
ESE

 7 / 14 mph 57 / 56°F 96%
Low level cloud: 96%
Mid level cloud: 66%
High level cloud: 94%
Most Significant Cloud Type: low
100%
0.1 In
06:00

W
W

 8 / 17 mph 57 / 55°F 98%
Low level cloud: 96%
Mid level cloud: 100%
High level cloud: 21%
Most Significant Cloud Type: low
100%
0.0 In
12:00

SW
SW

 8 / 17 mph 55 / 52°F 96%
Low level cloud: 92%
Mid level cloud: 57%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.2 In
18:00

WNW
WNW

 9 / 18 mph 60 / 60°F 97%
Low level cloud: 92%
Mid level cloud: 14%
High level cloud: 0%
Most Significant Cloud Type: low
96%
0.0 In
Mon 27
May		00:00

ESE
ESE

 4 / 9 mph 52 / 51°F 93%
Low level cloud: 25%
Mid level cloud: 31%
High level cloud: 3%
Most Significant Cloud Type: low
36%
0.0 In
06:00

WNW
WNW

 5 / 11 mph 58 / 58°F 93%
Low level cloud: 19%
Mid level cloud: 18%
High level cloud: 3%
Most Significant Cloud Type: low
25%
0.0 In
12:00

NNW
NNW

 6 / 13 mph 65 / 65°F 73%
Low level cloud: 24%
Mid level cloud: 29%
High level cloud: 0%
Most Significant Cloud Type: low
34%
0.0 In
18:00

WNW
WNW

 9 / 18 mph 61 / 61°F 91%
Low level cloud: 94%
Mid level cloud: 31%
High level cloud: 0%
Most Significant Cloud Type: low
100%
0.0 In
Tue 28
May		00:00

N
N

 5 / 11 mph 57 / 57°F 93%
Low level cloud: 50%
Mid level cloud: 44%
High level cloud: 16%
Most Significant Cloud Type: low
67%
0.1 In
06:00

SSW
SSW

 11 / 23 mph 58 / 55°F 96%
Low level cloud: 100%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.0 In
12:00

SE
SE

 6 / 13 mph 64 / 64°F 73%
Low level cloud: 7%
Mid level cloud: 15%
High level cloud: 0%
Most Significant Cloud Type: low
11%
0.0 In
18:00

NW
NW

 15 / 31 mph 54 / 50°F 76%
Low level cloud: 16%
Mid level cloud: 10%
High level cloud: 0%
Most Significant Cloud Type: low
19%
0.3 In
Wed 29
May		00:00

NE
NE

 3 / 6 mph 59 / 59°F 90%
Low level cloud: 7%
Mid level cloud: 13%
High level cloud: 32%
Most Significant Cloud Type: low
15%
0.0 In
06:00

NW
NW

 15 / 32 mph 50 / 44°F 78%
Low level cloud: 56%
Mid level cloud: 25%
High level cloud: 0%
Most Significant Cloud Type: low
64%
0.0 In
12:00

ESE
ESE

 13 / 28 mph 63 / 63°F 81%
Low level cloud: 6%
Mid level cloud: 6%
High level cloud: 33%
Most Significant Cloud Type: low
11%
0.0 In
18:00

WNW
WNW

 15 / 32 mph 55 / 51°F 77%
Low level cloud: 15%
Mid level cloud: 30%
High level cloud: 1%
Most Significant Cloud Type: low
25%
0.1 In
Thu 30
May		00:00

ENE
ENE

 6 / 14 mph 53 / 51°F 91%
Low level cloud: 0%
Mid level cloud: 27%
High level cloud: 16%
Most Significant Cloud Type: medium
27%
0.0 In
06:00

NW
NW

 6 / 13 mph 51 / 49°F 85%
Low level cloud: 26%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: low
26%
0.0 In
12:00

E
E

 13 / 28 mph 65 / 65°F 76%
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 10%
Most Significant Cloud Type: high
9%
0.0 In
18:00

SW
SW

 9 / 19 mph 57 / 55°F 79%
Low level cloud: 18%
Mid level cloud: 21%
High level cloud: 100%
Most Significant Cloud Type: low
36%
0.0 In
Fri 31
May		00:00

NE
NE

 8 / 16 mph 56 / 54°F 94%
Low level cloud: 7%
Mid level cloud: 6%
High level cloud: 0%
Most Significant Cloud Type: low
8%
0.0 In
06:00

SSW
SSW

 12 / 26 mph 54 / 51°F 98%
Low level cloud: 100%
Mid level cloud: 98%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.1 In
12:00

ENE
ENE

 11 / 24 mph 67 / 67°F 70%
Low level cloud: 0%
Mid level cloud: 5%
High level cloud: 0%
Most Significant Cloud Type: medium
4%
0.0 In
18:00

W
W

 11 / 23 mph 60 / 60°F 87%
Low level cloud: 73%
Mid level cloud: 1%
High level cloud: 0%
Most Significant Cloud Type: low
73%
0.1 In
Sat 01
Jun		00:00

NNE
NNE

 7 / 14 mph 54 / 52°F 87%
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
06:00

SW
SW

 11 / 23 mph 49 / 45°F 85%
Low level cloud: 69%
Mid level cloud: 19%
High level cloud: 0%
Most Significant Cloud Type: low
76%
0.0 In
12:00

N
N

 13 / 28 mph 64 / 64°F 69%
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 6%
Most Significant Cloud Type: high
6%
0.0 In
18:00

SW
SW

 17 / 36 mph 56 / 52°F 83%
Low level cloud: 44%
Mid level cloud: 30%
High level cloud: 0%
Most Significant Cloud Type: low
54%
0.1 In

Other Locations Near to Fal

The day label given represents the local day relative to the local time for the location you are looking at.
(More Info)

Day

This time is corrected for local time zones and where possible for daylight saving times.
(More Info)

Local Time

The wind direction we use on this page is the direction the wind is coming from, given in a 16 point compass format.
(More Info)

Dir

This refers to the sustained average wind speed, normally averaged over a period of 10 minutes for up to 3 hrs.
(More Info)

Speed/
Gust

Temperature from our forecast perspective are fairly well defined, they are what we would expect to measure in a standard meteorological screen (in other words, shaded and well ventilated) at 2 metres above ground level.
(More Info)

Temp/
Feels Like

The relative humidity is the percent of saturation humidity, generally calculated in relation to saturated vapour density.
(More Info)

Humidity

The value given is a total predicted for the previous 3 hrs and includes the time of the forecast being looked at.
(More Info)

Precip Amount

The total amount of cloud as a percentage is derived from looking at cloud cover throughout the atmosphere and estimating how these combine when looked at from the ground.
(More Info)

Cloud Amount

Here we try to capture the feel of the weather as an image – it will never be perfect but is useful for a quick overview.
(More Info)

Weather

When we measure for forecast air pressure we are normally doing this relative to a certain height and most commonly relative to Mean Sea Level.
(More Info)

Pressure