Local Weather

Papa Stronsay 14 Day Long Range Forecast

14 Day weather providing an extended long range forecast outlook for Papa Stronsay

Orkney Islands, United Kingdom

Long range weather outlook for Papa Stronsay includes 14 day forecast summary:

Over the next 14 days the Papa Stronsay forecast suggests the average daytime maximum temperature will be around 8°C, with a high for the two weeks of 9°C expected on the afternoon of Thursday 7th. The mean minimum temperature will be 6°C, dipping to its lowest on the afternoon of Friday 8th at 5°C. Expect the next 14 days have some days seeing a little precipitation and some days with rain or sleet. Predictions are Thursday 7th will have the most precipitation with an accumulation of around 8.0mm. On the whole winds are likely to be fresh. Expect the strongest wind on the afternoon of Thursday 7th, coming from a south easterly direction, and reaching around 46mph.

DayLocal TimeDirSpeed/
Gust
Temp/
Feels Like
HumidityPressureCloud AmountPrecip AmountWeather
Sun 03
Dec
18:00

E
E

19 / 28 mph 43 / 34°F 69% 1013 mb
Low level cloud: 50%
Mid level cloud: 24%
High level cloud: 8%
Most Significant Cloud Type: low
59%
Expect 0.02 In of precipitation over the past 3 hours.
0.02 In
21:00

E
E

19 / 29 mph 43 / 35°F 69% 1013 mb
Low level cloud: 55%
Mid level cloud: 22%
High level cloud: 0%
Most Significant Cloud Type: low
62%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
Mon 04
Dec
00:00

ENE
ENE

21 / 30 mph 43 / 34°F 69% 1013 mb
Low level cloud: 66%
Mid level cloud: 25%
High level cloud: 0%
Most Significant Cloud Type: low
74%
Expect 0.02 In of precipitation over the past 3 hours.
0.02 In
03:00

E
E

22 / 32 mph 43 / 34°F 72% 1013 mb
Low level cloud: 65%
Mid level cloud: 31%
High level cloud: 0%
Most Significant Cloud Type: low
75%
Expect 0.02 In of precipitation over the past 3 hours.
0.02 In
06:00

E
E

21 / 31 mph 43 / 34°F 69% 1012 mb
Low level cloud: 63%
Mid level cloud: 41%
High level cloud: 0%
Most Significant Cloud Type: low
77%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
09:00

ENE
ENE

20 / 29 mph 43 / 35°F 68% 1013 mb
Low level cloud: 65%
Mid level cloud: 45%
High level cloud: 0%
Most Significant Cloud Type: low
80%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
12:00

ENE
ENE

20 / 31 mph 43 / 34°F 65% 1014 mb
Low level cloud: 47%
Mid level cloud: 30%
High level cloud: 0%
Most Significant Cloud Type: low
57%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
15:00

ENE
ENE

18 / 29 mph 43 / 35°F 65% 1013 mb
Low level cloud: 40%
Mid level cloud: 13%
High level cloud: 1%
Most Significant Cloud Type: low
44%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
18:00

ENE
ENE

15 / 23 mph 43 / 35°F 69% 1014 mb
Low level cloud: 64%
Mid level cloud: 34%
High level cloud: 2%
Most Significant Cloud Type: low
76%
Expect 0.02 In of precipitation over the past 3 hours.
0.02 In
21:00

ENE
ENE

11 / 15 mph 43 / 37°F 68% 1015 mb
Low level cloud: 33%
Mid level cloud: 46%
High level cloud: 4%
Most Significant Cloud Type: low
49%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
Tue 05
Dec
00:00

ENE
ENE

7 / 12 mph 42 / 37°F 63% 1015 mb
Low level cloud: 35%
Mid level cloud: 31%
High level cloud: 3%
Most Significant Cloud Type: low
45%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
03:00

NE
NE

5 / 8 mph 41 / 38°F 64% 1015 mb
Low level cloud: 23%
Mid level cloud: 46%
High level cloud: 0%
Most Significant Cloud Type: low
39%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
06:00

ENE
ENE

4 / 6 mph 41 / 39°F 66% 1015 mb
Low level cloud: 17%
Mid level cloud: 46%
High level cloud: 4%
Most Significant Cloud Type: low
33%
Expect 0.04 In of precipitation over the past 3 hours.
0.04 In
09:00

SE
SE

4 / 6 mph 42 / 39°F 68% 1016 mb
Low level cloud: 11%
Mid level cloud: 13%
High level cloud: 6%
Most Significant Cloud Type: low
15%
Expect 0.04 In of precipitation over the past 3 hours.
0.04 In
12:00

SSW
SSW

6 / 8 mph 42 / 38°F 70% 1016 mb
Low level cloud: 8%
Mid level cloud: 14%
High level cloud: 4%
Most Significant Cloud Type: low
13%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
15:00

SW
SW

8 / 10 mph 43 / 38°F 74% 1015 mb
Low level cloud: 35%
Mid level cloud: 18%
High level cloud: 2%
Most Significant Cloud Type: low
41%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
18:00

SW
SW

6 / 7 mph 42 / 38°F 75% 1015 mb
Low level cloud: 41%
Mid level cloud: 15%
High level cloud: 0%
Most Significant Cloud Type: low
46%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
21:00

SW
SW

5 / 6 mph 42 / 39°F 75% 1015 mb
Low level cloud: 33%
Mid level cloud: 7%
High level cloud: 0%
Most Significant Cloud Type: low
35%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
Wed 06
Dec
00:00

SW
SW

5 / 5 mph 43 / 40°F 73% 1015 mb
Low level cloud: 6%
Mid level cloud: 7%
High level cloud: 0%
Most Significant Cloud Type: low
8%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
03:00

SSW
SSW

6 / 9 mph 42 / 38°F 67% 1014 mb
Low level cloud: 1%
Mid level cloud: 8%
High level cloud: 0%
Most Significant Cloud Type: medium
11%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
06:00

SSE
SSE

11 / 18 mph 41 / 35°F 64% 1014 mb
Low level cloud: 17%
Mid level cloud: 8%
High level cloud: 0%
Most Significant Cloud Type: low
20%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
09:00

SSE
SSE

18 / 24 mph 43 / 35°F 65% 1013 mb
Low level cloud: 18%
Mid level cloud: 6%
High level cloud: 0%
Most Significant Cloud Type: low
20%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
12:00

SSE
SSE

23 / 27 mph 46 / 37°F 66% 1013 mb
Low level cloud: 30%
Mid level cloud: 4%
High level cloud: 93%
Most Significant Cloud Type: low
42%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
15:00

SSE
SSE

26 / 29 mph 47 / 39°F 63% 1011 mb
Low level cloud: 48%
Mid level cloud: 66%
High level cloud: 100%
Most Significant Cloud Type: low
83%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
18:00

SSE
SSE

33 / 38 mph 46 / 36°F 64% 1010 mb
Low level cloud: 52%
Mid level cloud: 100%
High level cloud: 18%
Most Significant Cloud Type: low
89%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
21:00

SE
SE

36 / 52 mph 44 / 33°F 68% 1008 mb
Low level cloud: 36%
Mid level cloud: 44%
High level cloud: 100%
Most Significant Cloud Type: low
62%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
Thu 07
Dec
00:00

SE
SE

39 / 45 mph 45 / 34°F 78% 1006 mb
Low level cloud: 83%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
100%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
03:00

SE
SE

43 / 54 mph 44 / 32°F 90% 1002 mb
Low level cloud: 100%
Mid level cloud: 100%
High level cloud: 10%
Most Significant Cloud Type: low
100%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
06:00

SE
SE

41 / 64 mph 43 / 31°F 90% 999 mb
Low level cloud: 100%
Mid level cloud: 99%
High level cloud: 97%
Most Significant Cloud Type: low
100%
Expect 0.05 In of precipitation over the past 3 hours.
0.05 In
09:00

SE
SE

43 / 68 mph 45 / 34°F 90% 996 mb
Low level cloud: 100%
Mid level cloud: 39%
High level cloud: 100%
Most Significant Cloud Type: low
100%
Expect 0.02 In of precipitation over the past 3 hours.
0.02 In
12:00

SE
SE

42 / 60 mph 47 / 37°F 93% 991 mb
Low level cloud: 100%
Mid level cloud: 100%
High level cloud: 33%
Most Significant Cloud Type: low
100%
Expect 0.04 In of precipitation over the past 3 hours.
0.04 In
15:00

SSE
SSE

47 / 57 mph 48 / 37°F 91% 986 mb
Low level cloud: 100%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
100%
Expect 0.10 In of precipitation over the past 3 hours.
0.10 In
18:00

SSE
SSE

43 / 58 mph 47 / 37°F 89% 984 mb
Low level cloud: 100%
Mid level cloud: 20%
High level cloud: 100%
Most Significant Cloud Type: low
100%
Expect 0.06 In of precipitation over the past 3 hours.
0.06 In
21:00

SSE
SSE

44 / 78 mph 46 / 35°F 84% 982 mb
Low level cloud: 80%
Mid level cloud: 19%
High level cloud: 0%
Most Significant Cloud Type: low
86%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
Fri 08
Dec
00:00

SSE
SSE

37 / 75 mph 45 / 34°F 82% 982 mb
Low level cloud: 30%
Mid level cloud: 75%
High level cloud: 100%
Most Significant Cloud Type: low
67%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
03:00

SSE
SSE

36 / 66 mph 46 / 36°F 76% 983 mb
Low level cloud: 0%
Mid level cloud: 65%
High level cloud: 61%
Most Significant Cloud Type: medium
67%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
06:00

S
S

38 / 62 mph 47 / 37°F 72% 984 mb
Low level cloud: 0%
Mid level cloud: 98%
High level cloud: 88%
Most Significant Cloud Type: medium
100%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
09:00

S
S

34 / 72 mph 44 / 34°F 68% 986 mb
Low level cloud: 0%
Mid level cloud: 6%
High level cloud: 100%
Most Significant Cloud Type: medium
9%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
12:00

SSE
SSE

39 / 81 mph 42 / 30°F 71% 986 mb
Low level cloud: 0%
Mid level cloud: 5%
High level cloud: 20%
Most Significant Cloud Type: medium
5%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
15:00

SSE
SSE

44 / 91 mph 41 / 27°F 71% 985 mb
Low level cloud: 36%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
83%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
18:00

S
S

41 / 86 mph 42 / 29°F 72% 984 mb
Low level cloud: 39%
Mid level cloud: 63%
High level cloud: 32%
Most Significant Cloud Type: low
65%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
21:00

S
S

40 / 81 mph 44 / 32°F 82% 986 mb
Low level cloud: 98%
Mid level cloud: 100%
High level cloud: 0%
Most Significant Cloud Type: low
100%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
Sat 09
Dec
00:00

SW
SW

39 / 77 mph 46 / 35°F 84% 988 mb
Low level cloud: 98%
Mid level cloud: 70%
High level cloud: 1%
Most Significant Cloud Type: low
100%
Expect 0.07 In of precipitation over the past 3 hours.
0.07 In
03:00

SW
SW

32 / 62 mph 46 / 37°F 79% 992 mb
Low level cloud: 81%
Mid level cloud: 33%
High level cloud: 0%
Most Significant Cloud Type: low
92%
Expect 0.03 In of precipitation over the past 3 hours.
0.03 In
06:00

SW
SW

30 / 56 mph 47 / 38°F 80% 995 mb
Low level cloud: 95%
Mid level cloud: 39%
High level cloud: 0%
Most Significant Cloud Type: low
100%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
09:00

SW
SW

21 / 43 mph 45 / 37°F 81% 999 mb
Low level cloud: 87%
Mid level cloud: 15%
High level cloud: 2%
Most Significant Cloud Type: low
92%
Expect 0.02 In of precipitation over the past 3 hours.
0.02 In
12:00

SSW
SSW

19 / 41 mph 44 / 36°F 83% 1000 mb
Low level cloud: 61%
Mid level cloud: 47%
High level cloud: 100%
Most Significant Cloud Type: low
89%
Expect 0.01 In of precipitation over the past 3 hours.
0.01 In
15:00

S
S

21 / 43 mph 43 / 35°F 84% 999 mb
Low level cloud: 44%
Mid level cloud: 51%
High level cloud: 86%
Most Significant Cloud Type: low
71%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
18:00

S
S

27 / 56 mph 44 / 34°F 82% 997 mb
Low level cloud: 0%
Mid level cloud: 28%
High level cloud: 15%
Most Significant Cloud Type: medium
28%
Expect 0.00 In of precipitation over the past 3 hours.
0.00 In
21:00

S
S

36 / 61 mph 45 / 34°F 91% 994 mb
Low level cloud: 100%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
100%
Expect 0.15 In of precipitation over the past 3 hours.
0.15 In
DayLocal TimeDirSpeed/
Gust
Temp/
Feels Like
HumidityPressureCloud AmountPrecip AmountWeather
Sun 10
Dec
00:00

ESE
ESE

25 / 52 mph 49 / 41°F 64% 1009 mb
Low level cloud: 43%
Mid level cloud: 0%
High level cloud: 100%
Most Significant Cloud Type: low
55%
0.00 In
06:00

ESE
ESE

29 / 61 mph 43 / 32°F 86% 990 mb
Low level cloud: 93%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.00 In
12:00

SE
SE

31 / 65 mph 54 / 47°F 87% 992 mb
Low level cloud: 85%
Mid level cloud: 67%
High level cloud: 33%
Most Significant Cloud Type: low
100%
0.00 In
18:00

S
S

12 / 25 mph 48 / 43°F 78% 997 mb
Low level cloud: 0%
Mid level cloud: 6%
High level cloud: 4%
Most Significant Cloud Type: medium
6%
0.00 In
Mon 11
Dec
00:00

SE
SE

13 / 27 mph 46 / 39°F 93% 977 mb
Low level cloud: 97%
Mid level cloud: 85%
High level cloud: 32%
Most Significant Cloud Type: low
100%
0.00 In
06:00

SE
SE

10 / 21 mph 47 / 42°F 74% 982 mb
Low level cloud: 0%
Mid level cloud: 2%
High level cloud: 2%
Most Significant Cloud Type: medium
2%
0.00 In
12:00

WSW
WSW

13 / 28 mph 43 / 36°F 86% 980 mb
Low level cloud: 96%
Mid level cloud: 94%
High level cloud: 80%
Most Significant Cloud Type: low
100%
0.00 In
18:00

WNW
WNW

19 / 40 mph 47 / 39°F 80% 988 mb
Low level cloud: 27%
Mid level cloud: 5%
High level cloud: 32%
Most Significant Cloud Type: low
32%
0.00 In
Tue 12
Dec
00:00

S
S

29 / 61 mph 46 / 37°F 76% 985 mb
Low level cloud: 49%
Mid level cloud: 89%
High level cloud: 0%
Most Significant Cloud Type: low
80%
0.00 In
06:00

N
N

30 / 62 mph 42 / 31°F 76% 996 mb
Low level cloud: 86%
Mid level cloud: 15%
High level cloud: 5%
Most Significant Cloud Type: low
91%
0.04 In
12:00

W
W

21 / 44 mph 47 / 40°F 88% 989 mb
Low level cloud: 54%
Mid level cloud: 47%
High level cloud: 32%
Most Significant Cloud Type: low
74%
0.17 In
18:00

NNE
NNE

29 / 60 mph 41 / 29°F 77% 1004 mb
Low level cloud: 98%
Mid level cloud: 97%
High level cloud: 8%
Most Significant Cloud Type: low
100%
0.09 In
Wed 13
Dec
00:00

NW
NW

30 / 63 mph 45 / 35°F 86% 1001 mb
Low level cloud: 71%
Mid level cloud: 44%
High level cloud: 2%
Most Significant Cloud Type: low
86%
0.04 In
06:00

NE
NE

28 / 59 mph 42 / 31°F 81% 1006 mb
Low level cloud: 98%
Mid level cloud: 54%
High level cloud: 33%
Most Significant Cloud Type: low
100%
0.07 In
12:00

WNW
WNW

27 / 57 mph 47 / 38°F 76% 1011 mb
Low level cloud: 97%
Mid level cloud: 4%
High level cloud: 51%
Most Significant Cloud Type: low
100%
0.08 In
18:00

ENE
ENE

25 / 52 mph 47 / 38°F 85% 1000 mb
Low level cloud: 82%
Mid level cloud: 59%
High level cloud: 11%
Most Significant Cloud Type: low
100%
0.11 In
Thu 14
Dec
00:00

SSW
SSW

24 / 51 mph 44 / 35°F 87% 1006 mb
Low level cloud: 99%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.08 In
06:00

ENE
ENE

36 / 76 mph 43 / 32°F 89% 990 mb
Low level cloud: 99%
Mid level cloud: 92%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.14 In
12:00

SW
SW

29 / 61 mph 53 / 46°F 90% 1000 mb
Low level cloud: 100%
Mid level cloud: 75%
High level cloud: 19%
Most Significant Cloud Type: low
100%
0.13 In
18:00

NNW
NNW

30 / 64 mph 53 / 46°F 85% 976 mb
Low level cloud: 98%
Mid level cloud: 22%
High level cloud: 0%
Most Significant Cloud Type: low
100%
0.33 In
Fri 15
Dec
00:00

WSW
WSW

40 / 85 mph 48 / 38°F 80% 1001 mb
Low level cloud: 9%
Mid level cloud: 5%
High level cloud: 0%
Most Significant Cloud Type: low
10%
0.01 In
06:00

W
W

30 / 63 mph 45 / 36°F 85% 987 mb
Low level cloud: 75%
Mid level cloud: 73%
High level cloud: 0%
Most Significant Cloud Type: low
100%
0.14 In
12:00

WSW
WSW

32 / 66 mph 44 / 34°F 83% 1005 mb
Low level cloud: 79%
Mid level cloud: 100%
High level cloud: 0%
Most Significant Cloud Type: low
100%
0.14 In
18:00

WNW
WNW

36 / 75 mph 48 / 39°F 86% 1001 mb
Low level cloud: 94%
Mid level cloud: 43%
High level cloud: 8%
Most Significant Cloud Type: low
100%
0.10 In
Sat 16
Dec
00:00

WSW
WSW

31 / 65 mph 44 / 34°F 70% 1017 mb
Low level cloud: 3%
Mid level cloud: 18%
High level cloud: 33%
Most Significant Cloud Type: medium
26%
0.08 In
06:00

NW
NW

32 / 67 mph 45 / 34°F 77% 1014 mb
Low level cloud: 40%
Mid level cloud: 68%
High level cloud: 0%
Most Significant Cloud Type: low
63%
0.09 In
12:00

SW
SW

30 / 62 mph 46 / 37°F 78% 1012 mb
Low level cloud: 54%
Mid level cloud: 77%
High level cloud: 0%
Most Significant Cloud Type: low
81%
0.05 In
18:00

NNW
NNW

28 / 59 mph 46 / 36°F 74% 1022 mb
Low level cloud: 87%
Mid level cloud: 5%
High level cloud: 0%
Most Significant Cloud Type: low
88%
0.05 In
Sun 17
Dec
00:00

SW
SW

18 / 37 mph 44 / 37°F 72% 1017 mb
Low level cloud: 0%
Mid level cloud: 23%
High level cloud: 0%
Most Significant Cloud Type: medium
23%
0.04 In
06:00

N
N

20 / 42 mph 45 / 37°F 73% 1023 mb
Low level cloud: 99%
Mid level cloud: 25%
High level cloud: 9%
Most Significant Cloud Type: low
100%
0.01 In
12:00

SW
SW

32 / 68 mph 46 / 36°F 83% 1013 mb
Low level cloud: 98%
Mid level cloud: 86%
High level cloud: 0%
Most Significant Cloud Type: low
100%
0.01 In
18:00

NNW
NNW

17 / 36 mph 45 / 37°F 79% 1023 mb
Low level cloud: 79%
Mid level cloud: 54%
High level cloud: 0%
Most Significant Cloud Type: low
97%
0.02 In
Mon 18
Dec
00:00

SSW
SSW

21 / 44 mph 45 / 37°F 82% 1014 mb
Low level cloud: 88%
Mid level cloud: 100%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.08 In
06:00

NNW
NNW

14 / 30 mph 45 / 38°F 71% 1023 mb
Low level cloud: 63%
Mid level cloud: 26%
High level cloud: 91%
Most Significant Cloud Type: low
83%
0.11 In
12:00

WNW
WNW

17 / 36 mph 48 / 42°F 87% 1009 mb
Low level cloud: 88%
Mid level cloud: 70%
High level cloud: 100%
Most Significant Cloud Type: low
100%
0.09 In
18:00

W
W

5 / 10 mph 45 / 43°F 66% 1025 mb
Low level cloud: 6%
Mid level cloud: 46%
High level cloud: 100%
Most Significant Cloud Type: medium
67%
0.00 In

Other Locations Near to Papa Stronsay

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