Frequently Asked Questions

Add team members

You can add, remove, or update a team member and their alert sets from your alerts page at any time, by selecting the Team Alerts tab.

Team members can be invited via Email or SMS message; Once a member has been verified by ONE of these methods, you can then enter the other point of contact for that member.  For example, once a member has been added via email, their contact can then be updated to include a phone number for SMS alerts.

After the member has been verified, you can assign an alert set.  If a member already has an alert set assigned, you can update their alert sets, contact information, or alert types, by selecting the small pencil icon below the member's tile.

Create/Edit/Delete Alert Sets

At the bottom of the Team Alerts page are the Alert Sets, the group of alerts that can be triggered to send notifications to your team.  From here you may create, edit, delete, or duplicate up to 8 separate alert sets with up to 10 parameters each.

Once an alert set is created, you may edit, duplicate, or delete the set from the icons at the bottom of the tile.  Within each alert set you can name the set, add a descriptive header (maybe the actions required when alerted), select the station from which the alerts are triggered, set the frequency at which alerts are sent, and then select the individual alert parameters.

For suggestions of existing alert sets, there are three premade sets available when you select 'Create Alert Set'.  These sets are based on general safety and maintenance guidelines, and can be edited to fit your specific needs or uses once created.

Assign Alert Sets to Team Members

Once team members are verified, and alert sets are created, you can assign those sets to the team members and choose how those alerts are sent; They can receive those alerts via email, SMS, or both.  Next, you will 'add alert set' to the team member, then you can save this update.  Always be sure to select the add option before saving, otherwise the alert will not be assigned to that member.

PLEASE NOTE: Alert frequency cannot be updated per team member's preference, only as a whole set.  i.e. One team member cannot receive more or less frequent alerts for a given set, than other members.

We're updating our SMS alert system. Instead of a strict daily limit of 10 messages, you'll now have access to an SMS bank of up to 70 alerts, accrued at a rate of 10 messages per day. This allows for more flexibility, especially during severe weather events.

Why is this change happening?

This update gives you more control over your weather alerts during storms or critical events like hurricanes while ensuring you have enough alerts when it matters most.

How does the new system work?

• You will receive 10 new SMS alerts each day.
• Unused alerts roll over and accumulate up to a maximum of 70 alerts.
• Once the 70 alert limit is reached, no new alerts will be added until you use some.

What happens if I reach my limit?

If you exhaust the number of alerts accrued in your bank, no additional SMS alerts will be sent until you receive 10 more alerts the following day. However, you can still access all your alerts through the AWN app.

Do I need to do anything?

Ensure you have the latest version of the AWN App installed to stay up to date. SMS alerts are an AWN+ premium feature, so you'll need to upgrade your account to access this enhanced alert system. Get an additional 10% off a yearly subscription.

Here at Ambient Weather, We are here to provide weather data that fits your needs. 

Data is available through our Ambient Weather Network Data suite.

The link below explains more about the suite 

https://ambientweather.com/awn-data-suite

If you are interested in accessing data from your area, you can complete the contract development form. 
This will allow us to gather information about your needs so we may assist fully.

https://ambientweather.com/awn-contract-development

We have recently redesigned the Ambient Weather Network Dashboard based on customer feedback requesting a more streamlined experience.

As part of the redesign, the tiles have been updated with rounded corners and the tile banner and menu have a new appearance, as shown in the examples below.

What is Evapotranspiration?

Evapotranspiration (ET) is a measure of how much water is lost from the soil and plants into the atmosphere. It combines two processes:

1. Evaporation: Water evaporating directly from soil, grass, and other surfaces
2. Transpiration: Water vapor released by plants through their leaves

Think of ET as "water demand" - on a hot, sunny, windy day, more water evaporates and plants need more water. On a cool, cloudy, calm day, less water is lost.

Why does ET matter?

ET helps you make smart watering decisions:

• Irrigation management: Know exactly how much water your lawn or crops lost today
• Water conservation: Avoid overwatering by replacing only what was lost
• Plant health: Understand when plants are experiencing water stress
• Cost savings: Reduce water bills by watering efficiently

For example, if ET shows 0.25 inches today, that's how much water your lawn needs to replace through rainfall or irrigation.

How do we calculate ET?

We use the FAO-56 Penman-Monteith method, which is the international gold standard for ET calculation. This method was developed by the United Nations Food and Agriculture Organization (FAO) and is trusted by agricultural researchers, irrigation managers, and water agencies worldwide.

What weather data do we use?

Our calculation uses real-time data from your weather station:

• Temperature (high and low) - Drives evaporation rate
• Humidity (high and low) - Lower humidity = more evaporation
• Solar radiation - More sun = more energy for evaporation
• Wind speed - Wind carries away moisture, increasing evaporation
• Your location (latitude and elevation) - Affects solar intensity and air pressure

The calculation process

The Penman-Monteith method considers how energy and moisture move through the atmosphere:

1. Solar energy: We calculate how much sun energy is available to evaporate water, accounting for:

   • Time of year (affects sun angle)
   • Your latitude (affects day length and intensity)
   • Cloud cover (estimated from measured vs. expected solar radiation)
   • How much sunlight grass reflects (about 23%)

2. Atmospheric conditions: We determine how "thirsty" the air is by calculating:

   • How much moisture the air can hold at current temperatures
   • How much moisture is actually in the air (from humidity readings)
   • Atmospheric pressure (varies with elevation)

3. Wind effect: We account for how wind speed helps move moisture away from surfaces

4. Energy balance: We combine all these factors using the Penman-Monteith equation to determine the daily water loss in millimeters or inches per day

What assumptions does the calculation make?

To provide a standardized measurement, we make several scientifically-validated assumptions:

Reference crop (grass)

• We calculate ET for a standard grass reference crop - well-watered, 12cm (5 inch) tall grass
• This provides a baseline that works for lawns and can be adjusted for other crops
• Different plants (trees, vegetables, etc.) may use 50-150% of reference ET depending on the crop type

Daily timeframe

• ET is calculated as a daily total (inches or mm per day) that resets at midnight
• The displayed value shows the current day's accumulation so far - it builds throughout the day as temperatures rise, solar radiation accumulates, and conditions change
• ET values are most accurate late in the day (evening/night) when the full daily temperature range and solar radiation have been captured
• Early morning ET values will appear lower because the day's high temperature and peak solar radiation haven't occurred yet
• Soil heat storage is assumed to be negligible over a full day (balances out)

Standard height

• Wind speed is assumed to be measured at or adjusted to 2 meters (6.5 feet) height
• This is the meteorological standard height for wind measurements

Well-watered conditions

• The calculation assumes no water stress - that water is available for plants to use
• Actual evaporation may be lower in drought conditions when soil is very dry

Minimum wind speed

• We use a minimum wind speed of 0.5 m/s (1.1 mph) even if measured wind is lower
• This prevents calculation errors in completely calm conditions and accounts for local air movement

What do the ET values mean?

ET is reported in both millimeters per day (mm/day) and inches per day (in/day).

Important: The ET value you see represents today's total so far since midnight. For the most accurate daily total, check ET in the late evening when the full day's weather conditions have been captured.

Typical ranges (complete 24-hour period):

• Cool/cloudy days: 1-3 mm/day (0.04-0.12 in/day)
• Moderate conditions: 5-7 mm/day (0.20-0.28 in/day)
• Hot summer days: 8-12 mm/day (0.31-0.47 in/day)
• Very hot/windy/dry: Over 12 mm/day (>0.47 in/day)

What if I don't have a lawn?

The reference ET (grass) is still useful! Multiply by a crop coefficient to adjust for your specific plants:

• Turf grass: 0.8-1.0
• Vegetables (mature): 0.9-1.2
• Trees/shrubs: 0.5-0.9
• Flowers: 0.6-1.0

For example, if ET shows 0.30 inches and you have mature tomatoes (coefficient ~1.1), your plants need about 0.33 inches of water.

How accurate is the calculation?

Our implementation has been validated against official FAO-56 test cases with 0.8% accuracy. This means our calculations match the international reference standard to within 1%.

The accuracy of your ET values depends on:

• Sensor quality: Accurate temperature, humidity, solar radiation, and wind readings are essential
• Sensor placement: Sensors should be properly positioned per manufacturer guidelines
• Location settings: Correct latitude and elevation in your station settings

When might ET be unavailable?

ET calculation requires multiple weather parameters. You won't see ET values if your station is missing:

• Solar radiation sensor (required)
• Temperature readings (high and low)
• Humidity readings (high and low)
• Wind speed data
• Location coordinates (latitude) or elevation

Additional resources

For more technical details about the Penman-Monteith method:

• FAO Irrigation and Drainage Paper 56 - Official methodology
• FAO Chapter 2: Penman-Monteith equation - Equation details
• University of Florida: ET Calculation Guide - Step-by-step methodology

Need help? If you have questions about your ET readings or want to learn more about using ET for irrigation scheduling, contact our support team.

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