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How to access and use weather
data from Agrimet weather
stations
Dr. Patty Skinkis
Viticulture Extension and Research
4/2015
Go to the following URL:
http://www.usbr.gov/pn/agrimet/
Select “Weather Data”
For data from a specific
year, select “Historical
Archive (Daily) Data
Access” to work data.
Find out what data are
available from each
weather station and
the units (need to
know for your search
and for later when
looking at data).
Select the station from
which you want to access
data.
Select the dates
of interest.
Select the weather data you
wish to summarize. Often the
most informational are min,
max, mean temperatures,
growing degree days and
precipitation. Keep in mind that
the growing degree days have a
upper threshold of 86°F, and
grapevines can have higher
threshold. You may wish to
calculate your own daily GDD
using the simple average
method (mean of max and min
temp – 50).
Click Submit at
bottom of page.
Here is an example of the
output that comes from the
selection of the weather station
parameters. To find out what
the headings mean, go back to
the prior selection page or see
“Types of weather data
collected by Agrimet Stations”
as shown in screen shot in page
2 of this document.
How to get the data into Excel?
Highlight the data, select copy,
and paste into an open Excel file.
How to get the data into Excel?
Highlight the data (starting with
column headings), select copy,
and paste into an open Excel file.
Go to “Data Tab”
Select “Text to Columns” and follow instructions for getting data
into columns: “fixed width”  select “next” if breaks look
correct select “finish”.
You are now ready to work with
your data. Consider summarizing
by the following:
•
Monthly data
•
Seasonal Data
•
Calculate your own daily
GDD = (Tmax + Tmin)/2 – 50
NOTE: For days where the GDD is negative,
count the day as a zero rather than a
negative number.
•
Make plots of daily and
monthly data.