Climate

Weather generator data and weather stations are required for SWAT+ to run.

SWAT+ Documentation

Read the SWAT+ Input/Output Documentation for Climate

Weather Stations

Weather stations are linked from all of your connection objects (channels, HRUs, etc.) in SWAT+. If you are coming from QSWAT+, it is much better to import stations either from the weather generator section, or the observed weather file importer than it is to create them manually.

By importing through one of the methods described below, your new stations will be automatically matched your spatial connection objects.

Import Weather Generator Data

Click the import data button to import weather generator (wgn) data for your project. If you installed the SWAT+ databases, this file will be selected by default along with the CFSR world table. USA wgn data is also available from this database; type wgn_us to use this table.

You may also add your own data to this database using the wgn and corresponding wgn_mon tables.

How to Use SQLite

Below the table name field is a check box asking if you are using observed weather data. By default (unchecked), when you click start import, weather stations will be created based on your wgn locations. If you are using observed weather data and prefer to have weather stations created based on this data, check this box--stations will not be created when you start import, and instead they will be created for you when you import your observed weather data files.

If you are not using observed weather data, it is important to leave the box unchecked so that weather stations are created for you.

CSV Import

If you do not want to use the SQLite database, you may import CSV files of your weather generator data. Two CSV files are required.

  1. Stations CSV file:

    • Columns id, name, lat, lon, elev, rain_yrs

    • id should be uniquely numbered

  2. Monthly values CSV file:

    • Columns id, wgn_id, month, tmp_max_ave, tmp_min_ave, tmp_max_sd, tmp_min_sd, pcp_ave, pcp_sd, pcp_skew, wet_dry, wet_wet, pcp_days, pcp_hhr, slr_ave, dew_ave, wnd_ave

    • id should be uniquely numbered

    • wgn_id corresponds to the id column from the stations file

Import Observed Weather Data

Import observed weather data from the top of the weather stations section. The data files may be in one of two formats: SWAT2012/Global Weather Data CFSR website format, or SWAT+.

After importing observed weather data, be sure to check your simulation run time to match your weather dates.

Please ensure the files you're importing are saved with UTF-8 encoding. Otherwise, you may get errors about reading the start date despite it appearing correctly formatted in your files.

You can open your files in Notepad++ and change the encoding via the Encoding menu in the top toolbar. It must be only UTF-8, not other variations.

SWAT2012/Global Weather Websites Format

Each measurement included in your data must have the following entry file names:

Measurement

Entry File

Precipitation

pcp.txt

Temperature

tmp.txt

Solar radiation

solar.txt

Relative humidity

rh.txt

Wind speed

wind.txt

Each entry file is a comma-separated list of stations. Each station name should have a corresponding .txt file (e.g., name p326-963 should have a p326-963.txt file).

ID

Name

Latitude

Longitude

Elevation

1

p326-963

32.628

-96.250

142.0

Each station file should have the first line as the starting day as YYYYMMDD (e.g., 19790101). The following lines are the measurement for each day, one line per day. For temperature, each line will be max,min (e.g., 10.138,-2.662).

Global weather data options are available on the SWAT website.

SWAT+ Format

Each measurement included in your data must have the following entry file names:

Measurement

Entry File

Precipitation

pcp.cli

Temperature

tmp.cli

Solar radiation

slr.cli

Relative humidity

hmd.cli

Wind speed

wnd.cli

Each entry file has a title line (any text allowed), followed by a heading line, followed by a list of filenames for each station. Filenames should be listed alphabetically.

pcp.cli: precipitation file names

filename

p326953.pcp

p326956.pcp

Each station file has a title line, followed by a heading line and data line for time and location. Measurements for each timestep are in the lines to follow. For temperature, the measurements will be listed as max then min.

Weather Generator Parameters

SWAT+ Input File

Database Tables

weather-wgn.cli

weather_wgn_cli

weather_wgn_cli_mon

weather_wgn_cli

Field

Type

Description

Units

Range

id

int

Auto-assigned identifier

name

text

Name of weather generator

lat

real

Latitude of weather station

deg.

+/-90

lon

real

Longitude of weather station

deg.

+/-180

elev

real

Elevation of weather station

m

0-5000

rain_yrs

int

Number of years of recorded maximum monthly 0.5h rainfall data

5-100

weather_wgn_cli_mon

Each entry in weather_wgn_cli will have 12 rows in weather_wgn_cli_mon.

Field

Type

Description

Units

Range

id

int

Auto-assigned identifier

wgn_id

int

ID of row in weather_wgn_cli

month

int

Month

tmp_max_ave

real

Average or mean daily maximum air temperature for month

°C

-30-50

tmp_min_ave

real

Average or mean daily minimum air temperature for month

°C

-40-40

tmp_max_sd

real

Standard deviation for daily maximum air temperature in month

°C

0.1-100

tmp_min_sd

real

Standard deviation for daily minimum air temperature in month

°C

0.1-30

pcp_ave

real

Average or mean total monthly precipitation

mm

0-600

pcp_sd

real

Standard deviation for the average daily precipitation

mm/day

0.1-50

pcp_skew

real

Skew coefficient for the average daily precipitation

mm

-50-20

wet_dry

real

Probability of a wet day after a dry day

0-0.95

wet_wet

real

Probability of a wet day after a wet day

0-0.95

pcp_days

real

Average number of days of precipitation in a month

0-31

pcp_hhr

real

Maximum 0.5 hour rainfall in entire period of record for month

mm

0-125

slr_ave

real

Average daily solar radiation for the month

MJ/m^2/day

0-750

dew_ave

real

Average daily dew point temperature for each month

°C

-50-25

wnd_ave

real

Average wind speed for the month

m/s

0-100

Weather Stations Parameters

SWAT+ Input File

Database Tables

weather-sta.cli

weather_sta_cli

weather_file

weather_sta_cli

When entering an observed weather file name in the station editor, you may start typing to search for existing weather files adding during the import step. If adding observed files manually, just type the name of the file (e.g., p326953.pcp), and put that file in the directory you plan to write input files (e.g., your TxtInOut). Files must be in SWAT+ format. If your weather data is in SWAT2012 format or from the Global Weather CFSR website, please use the import step to convert them to SWAT+.

Field

Type

Description

id

int

Auto-assigned identifier

name

text

Name of the weather station

wgn_id

int

ID of row in weather_wgn_cli

pcp

text

Precipitation gage filename or "sim" if simulated

tmp

text

Temperature gage filename or "sim" if simulated

slr

text

Solar radiation gage filename or "sim" if simulated

hmd

text

Relative humidity gage filename or "sim" if simulated

wnd

text

Wind speed gage filename or "sim" if simulated

wnd_dir

text

Wind direction gage filename

atmo_dep

text

Atmospheric deposition data file name

lat

real

Latitude of weather station

lon

real

Longitude of weather station

weather_file

This table is only used if you import observed weather data files. If entering stations manually, this table will not be populated.

Field

Type

Description

id

int

Auto-assigned identifier

filename

text

Name of the weather data file

type

text

Type of weather data: pcp, tmp, slr, hmd, wnd

lat

real

Latitude of weather station in file

lon

real

Longitude of weather station in file

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