WEATHER FOR BUSINESS

We supply weather data to businesses

Free Weather Plugin

Add this forecast to your website



Local Weather

Trinidad 14 Day Long Range Forecast

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

Colorado, United States Of America

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

Taking a look at Trinidad over the coming two weeks and the average daytime maximum temperature will be around 25°C, with a high for the two weeks of 30°C expected on the afternoon of Sunday 19th. The average minimum temperature will be 10°C, dipping to its lowest on the morning of Thursday 23rd at 6°C. The coming 14 days will have mixed overhead conditions with some days dry and some seeing a significant amount of rain. The current forecast indicates Wednesday 15th will have the most precipitation with an accumulation of around 16.0mm. On the whole winds are likely to be moderate. The forecast suggests the strongest wind will be on the afternoon of Monday 20th, coming from a south westerly direction, and reaching around 31mph. However, the forecast suggests maximum gusts on Tuesday evening.

DayLocal TimeDirSpeed/
Gust
Temp/
Feels Like
HumidityPressureCloud AmountPrecip AmountWeather
Mon 13
May
02:00

WSW
WSW

7 / 15 mph 50 / 47°F 72% 1013 mb
Low level cloud: 0%
Mid level cloud: 19%
High level cloud: 3%
Most Significant Cloud Type: medium
18%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
05:00

WSW
WSW

7 / 15 mph 48 / 45°F 66% 1013 mb
Low level cloud: 0%
Mid level cloud: 3%
High level cloud: 0%
Most Significant Cloud Type: medium
3%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
08:00

NW
NW

6 / 7 mph 62 / 60°F 38% 1012 mb
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
11:00

N
N

9 / 11 mph 69 / 68°F 27% 1010 mb
Low level cloud: 0%
Mid level cloud: 2%
High level cloud: 0%
Most Significant Cloud Type: medium
2%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
14:00

NNE
NNE

14 / 16 mph 72 / 72°F 23% 1008 mb
Low level cloud: 0%
Mid level cloud: 5%
High level cloud: 0%
Most Significant Cloud Type: medium
5%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
17:00

N
N

6 / 7 mph 73 / 69°F 26% 1007 mb
Low level cloud: 0%
Mid level cloud: 53%
High level cloud: 8%
Most Significant Cloud Type: medium
53%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
20:00

WSW
WSW

6 / 13 mph 56 / 54°F 50% 1011 mb
Low level cloud: 0%
Mid level cloud: 31%
High level cloud: 18%
Most Significant Cloud Type: medium
31%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
23:00

W
W

3 / 6 mph 52 / 53°F 58% 1011 mb
Low level cloud: 0%
Mid level cloud: 10%
High level cloud: 51%
Most Significant Cloud Type: medium
12%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Tue 14
May
20:00

SW
SW

2 / 4 mph 59 / 60°F 51% 1007 mb
Low level cloud: 0%
Mid level cloud: 18%
High level cloud: 14%
Most Significant Cloud Type: medium
18%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
23:00

WSW
WSW

4 / 6 mph 53 / 53°F 73% 1010 mb
Low level cloud: 0%
Mid level cloud: 10%
High level cloud: 16%
Most Significant Cloud Type: medium
11%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Wed 15
May
02:00

WSW
WSW

5 / 10 mph 51 / 49°F 70% 1008 mb
Low level cloud: 0%
Mid level cloud: 13%
High level cloud: 87%
Most Significant Cloud Type: medium
16%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
05:00

SW
SW

4 / 9 mph 52 / 51°F 61% 1008 mb
Low level cloud: 0%
Mid level cloud: 28%
High level cloud: 32%
Most Significant Cloud Type: medium
29%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
08:00

NNE
NNE

5 / 6 mph 65 / 63°F 43% 1008 mb
Low level cloud: 0%
Mid level cloud: 8%
High level cloud: 99%
Most Significant Cloud Type: medium
11%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
11:00

NE
NE

10 / 11 mph 71 / 69°F 37% 1006 mb
Low level cloud: 0%
Mid level cloud: 23%
High level cloud: 56%
Most Significant Cloud Type: medium
25%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
14:00

WSW
WSW

9 / 12 mph 52 / 47°F 85% 1010 mb
Low level cloud: 7%
Mid level cloud: 45%
High level cloud: 87%
Most Significant Cloud Type: medium
69%
Expect 0.4 In of precipitation over the past 3 hours.
0.4 In
17:00

SSW
SSW

6 / 6 mph 58 / 55°F 67% 1008 mb
Low level cloud: 0%
Mid level cloud: 44%
High level cloud: 4%
Most Significant Cloud Type: medium
44%
Expect 0.1 In of precipitation over the past 3 hours.
0.1 In
20:00

W
W

7 / 12 mph 53 / 50°F 79% 1009 mb
Low level cloud: 0%
Mid level cloud: 22%
High level cloud: 32%
Most Significant Cloud Type: medium
22%
Expect 0.1 In of precipitation over the past 3 hours.
0.1 In
23:00

NNE
NNE

11 / 12 mph 50 / 46°F 90% 1012 mb
Low level cloud: 61%
Mid level cloud: 84%
High level cloud: 28%
Most Significant Cloud Type: low
93%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Thu 16
May
02:00

NW
NW

5 / 5 mph 50 / 48°F 84% 1012 mb
Low level cloud: 15%
Mid level cloud: 44%
High level cloud: 54%
Most Significant Cloud Type: medium
87%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
05:00

NNW
NNW

5 / 7 mph 50 / 47°F 85% 1011 mb
Low level cloud: 10%
Mid level cloud: 27%
High level cloud: 68%
Most Significant Cloud Type: low
27%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
08:00

NNW
NNW

2 / 2 mph 55 / 54°F 73% 1011 mb
Low level cloud: 0%
Mid level cloud: 46%
High level cloud: 32%
Most Significant Cloud Type: medium
47%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
11:00

E
E

6 / 6 mph 63 / 61°F 57% 1009 mb
Low level cloud: 0%
Mid level cloud: 33%
High level cloud: 33%
Most Significant Cloud Type: medium
34%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
14:00

E
E

7 / 9 mph 68 / 65°F 45% 1007 mb
Low level cloud: 0%
Mid level cloud: 28%
High level cloud: 32%
Most Significant Cloud Type: medium
29%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
17:00

ESE
ESE

11 / 13 mph 64 / 62°F 54% 1007 mb
Low level cloud: 0%
Mid level cloud: 31%
High level cloud: 32%
Most Significant Cloud Type: medium
32%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
20:00

SSW
SSW

4 / 9 mph 55 / 52°F 73% 1009 mb
Low level cloud: 0%
Mid level cloud: 9%
High level cloud: 0%
Most Significant Cloud Type: medium
9%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
23:00

W
W

5 / 11 mph 51 / 49°F 74% 1009 mb
Low level cloud: 0%
Mid level cloud: 6%
High level cloud: 0%
Most Significant Cloud Type: medium
6%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Fri 17
May
02:00

WSW
WSW

4 / 9 mph 48 / 47°F 74% 1008 mb
Low level cloud: 0%
Mid level cloud: 5%
High level cloud: 0%
Most Significant Cloud Type: medium
5%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
05:00

SW
SW

6 / 12 mph 47 / 44°F 70% 1009 mb
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
08:00

SSW
SSW

5 / 6 mph 65 / 63°F 43% 1008 mb
Low level cloud: 0%
Mid level cloud: 2%
High level cloud: 0%
Most Significant Cloud Type: medium
1%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
11:00

W
W

1 / 1 mph 76 / 73°F 25% 1005 mb
Low level cloud: 0%
Mid level cloud: 1%
High level cloud: 0%
Most Significant Cloud Type: medium
1%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
14:00

N
N

3 / 4 mph 80 / 75°F 20% 1002 mb
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
17:00

NW
NW

2 / 2 mph 82 / 76°F 17% 1000 mb
Low level cloud: 0%
Mid level cloud: 11%
High level cloud: 0%
Most Significant Cloud Type: medium
11%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
20:00

SW
SW

12 / 25 mph 65 / 64°F 36% 1004 mb
Low level cloud: 0%
Mid level cloud: 26%
High level cloud: 0%
Most Significant Cloud Type: medium
26%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
23:00

WSW
WSW

12 / 24 mph 60 / 60°F 37% 1005 mb
Low level cloud: 0%
Mid level cloud: 11%
High level cloud: 0%
Most Significant Cloud Type: medium
11%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Sat 18
May
02:00

WSW
WSW

11 / 22 mph 57 / 55°F 40% 1006 mb
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
05:00

SW
SW

11 / 22 mph 56 / 53°F 36% 1007 mb
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
08:00

W
W

12 / 13 mph 74 / 73°F 24% 1006 mb
Low level cloud: 0%
Mid level cloud: 3%
High level cloud: 0%
Most Significant Cloud Type: medium
2%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
11:00

NW
NW

13 / 15 mph 81 / 76°F 19% 1006 mb
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
14:00

NNW
NNW

12 / 14 mph 83 / 78°F 20% 1005 mb
Low level cloud: 0%
Mid level cloud: 45%
High level cloud: 0%
Most Significant Cloud Type: medium
44%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
17:00

WNW
WNW

13 / 24 mph 62 / 60°F 58% 1010 mb
Low level cloud: 0%
Mid level cloud: 12%
High level cloud: 33%
Most Significant Cloud Type: medium
13%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
20:00

S
S

5 / 10 mph 63 / 61°F 54% 1012 mb
Low level cloud: 0%
Mid level cloud: 10%
High level cloud: 0%
Most Significant Cloud Type: medium
10%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
23:00

SW
SW

2 / 4 mph 56 / 56°F 56% 1013 mb
Low level cloud: 0%
Mid level cloud: 1%
High level cloud: 0%
Most Significant Cloud Type: high
0%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
Sun 19
May
02:00

SSW
SSW

1 / 2 mph 52 / 52°F 70% 1014 mb
Low level cloud: 0%
Mid level cloud: 5%
High level cloud: 0%
Most Significant Cloud Type: medium
4%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
05:00

SSW
SSW

6 / 12 mph 51 / 49°F 68% 1014 mb
Low level cloud: 0%
Mid level cloud: 4%
High level cloud: 0%
Most Significant Cloud Type: medium
3%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
08:00

SSW
SSW

6 / 7 mph 70 / 67°F 39% 1011 mb
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
11:00

SSW
SSW

15 / 18 mph 82 / 77°F 18% 1007 mb
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
14:00

WSW
WSW

18 / 20 mph 86 / 80°F 13% 1004 mb
Low level cloud: 0%
Mid level cloud: 21%
High level cloud: 99%
Most Significant Cloud Type: medium
25%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
17:00

W
W

21 / 27 mph 82 / 77°F 16% 1003 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 75%
Most Significant Cloud Type: high
74%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
20:00

WSW
WSW

11 / 24 mph 67 / 66°F 24% 1006 mb
Low level cloud: 0%
Mid level cloud: 2%
High level cloud: 16%
Most Significant Cloud Type: medium
2%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
23:00

SW
SW

9 / 19 mph 62 / 62°F 27% 1007 mb
Low level cloud: 0%
Mid level cloud: 7%
High level cloud: 33%
Most Significant Cloud Type: medium
8%
Expect 0.0 In of precipitation over the past 3 hours.
0.0 In
DayLocal TimeDirSpeed/
Gust
Temp/
Feels Like
HumidityPressureCloud AmountPrecip AmountWeather
Mon 20
May
05:00

NE
NE

7 / 13 mph 45 / 41°F 79% 1018 mb
Low level cloud: 12%
Mid level cloud: 32%
High level cloud: 0%
Most Significant Cloud Type: low
22%
0.0 In
11:00

SSE
SSE

19 / 35 mph 74 / 73°F 22% 1003 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
17:00

E
E

11 / 18 mph 64 / 64°F 44% 1011 mb
Low level cloud: 0%
Mid level cloud: 43%
High level cloud: 32%
Most Significant Cloud Type: medium
44%
0.0 In
23:00

SW
SW

9 / 19 mph 55 / 53°F 27% 1004 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
Tue 21
May
05:00

SSE
SSE

9 / 15 mph 48 / 44°F 70% 1017 mb
Low level cloud: 0%
Mid level cloud: 17%
High level cloud: 0%
Most Significant Cloud Type: medium
17%
0.0 In
17:00

ENE
ENE

19 / 32 mph 78 / 77°F 29% 1004 mb
Low level cloud: 0%
Mid level cloud: 23%
High level cloud: 0%
Most Significant Cloud Type: medium
23%
0.0 In
23:00

WSW
WSW

10 / 20 mph 50 / 47°F 25% 1009 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
Wed 22
May
05:00

SSE
SSE

4 / 7 mph 50 / 50°F 77% 1013 mb
Low level cloud: 0%
Mid level cloud: 9%
High level cloud: 100%
Most Significant Cloud Type: medium
13%
0.0 In
11:00

NNW
NNW

14 / 24 mph 69 / 69°F 15% 1009 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
17:00

SW
SW

13 / 21 mph 83 / 80°F 11% 1001 mb
Low level cloud: 0%
Mid level cloud: 3%
High level cloud: 0%
Most Significant Cloud Type: medium
2%
0.0 In
23:00

SE
SE

2 / 4 mph 50 / 51°F 39% 1017 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
Thu 23
May
05:00

SSW
SSW

10 / 21 mph 55 / 52°F 26% 1006 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 11%
Most Significant Cloud Type: high
11%
0.0 In
11:00

SE
SE

5 / 9 mph 68 / 68°F 23% 1015 mb
Low level cloud: 0%
Mid level cloud: 7%
High level cloud: 85%
Most Significant Cloud Type: medium
9%
0.0 In
17:00

W
W

22 / 37 mph 80 / 77°F 12% 1001 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
23:00

SSW
SSW

8 / 17 mph 57 / 55°F 37% 1014 mb
Low level cloud: 0%
Mid level cloud: 5%
High level cloud: 13%
Most Significant Cloud Type: medium
5%
0.0 In
Fri 24
May
05:00

SW
SW

10 / 22 mph 55 / 52°F 20% 1005 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 98%
Most Significant Cloud Type: high
97%
0.0 In
11:00

SSW
SSW

29 / 51 mph 74 / 76°F 39% 1009 mb
Low level cloud: 0%
Mid level cloud: 1%
High level cloud: 0%
Most Significant Cloud Type: medium
1%
0.0 In
17:00

W
W

22 / 36 mph 79 / 76°F 12% 998 mb
Low level cloud: 0%
Mid level cloud: 5%
High level cloud: 100%
Most Significant Cloud Type: medium
8%
0.0 In
23:00

SSW
SSW

25 / 45 mph 62 / 62°F 74% 1008 mb
Low level cloud: 0%
Mid level cloud: 13%
High level cloud: 18%
Most Significant Cloud Type: medium
13%
0.0 In
Sat 25
May
05:00

SW
SW

12 / 24 mph 53 / 49°F 24% 1005 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 25%
Most Significant Cloud Type: high
25%
0.0 In
11:00

SSW
SSW

23 / 40 mph 81 / 78°F 13% 1003 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
17:00

WNW
WNW

21 / 36 mph 73 / 73°F 15% 1003 mb
Low level cloud: 0%
Mid level cloud: 6%
High level cloud: 0%
Most Significant Cloud Type: medium
5%
0.0 In
23:00

SW
SW

12 / 26 mph 63 / 63°F 17% 1006 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 2%
Most Significant Cloud Type: high
2%
0.0 In
Sun 26
May
05:00

WSW
WSW

6 / 13 mph 46 / 43°F 27% 1017 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 33%
Most Significant Cloud Type: high
32%
0.0 In
11:00

NE
NE

8 / 13 mph 78 / 75°F 16% 1006 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 5%
Most Significant Cloud Type: high
4%
0.0 In
17:00

ENE
ENE

12 / 20 mph 74 / 73°F 16% 1013 mb
Low level cloud: 0%
Mid level cloud: 3%
High level cloud: 33%
Most Significant Cloud Type: medium
4%
0.0 In
23:00

SW
SW

9 / 19 mph 61 / 61°F 22% 1008 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
Mon 27
May
05:00

W
W

4 / 9 mph 47 / 46°F 43% 1023 mb
Low level cloud: 0%
Mid level cloud: 3%
High level cloud: 44%
Most Significant Cloud Type: medium
4%
0.0 In
11:00

E
E

4 / 8 mph 78 / 76°F 14% 1006 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
17:00

NE
NE

12 / 20 mph 73 / 73°F 23% 1017 mb
Low level cloud: 0%
Mid level cloud: 17%
High level cloud: 6%
Most Significant Cloud Type: medium
17%
0.0 In
23:00

SW
SW

10 / 21 mph 61 / 61°F 20% 1008 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In
Tue 28
May
05:00

WNW
WNW

5 / 9 mph 49 / 47°F 75% 1025 mb
Low level cloud: 0%
Mid level cloud: 16%
High level cloud: 0%
Most Significant Cloud Type: medium
15%
0.0 In
11:00

ESE
ESE

3 / 6 mph 82 / 78°F 11% 1007 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 4%
Most Significant Cloud Type: high
4%
0.0 In
17:00

S
S

13 / 22 mph 72 / 76°F 42% 1016 mb
Low level cloud: 0%
Mid level cloud: 15%
High level cloud: 0%
Most Significant Cloud Type: medium
14%
0.0 In
23:00

WSW
WSW

10 / 21 mph 63 / 63°F 17% 1011 mb
Low level cloud: 0%
Mid level cloud: 0%
High level cloud: 0%
Most Significant Cloud Type: high
0%
0.0 In

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