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Synoptic Data Viewer

The Synoptic Data Viewer allows anyone to visualize all publicly available observations aggregated by Synoptic in spatial, tabular, and graphical format, from a single source. It is optimized for a desktop experience but designed to accommodate mobile devices. The Explore, Table and Graph tabs (with Metadata Explore, Summary and Dashboard on the way) allow users to access real-time and historical observations in a customizable framework to gain observational insight and awareness. This article will walk through and detail key features of Synoptic Data Viewer. And don’t forget to check back! We’re in active development, updating and adding features frequently.


The Explore page is your source to view map-based snapshots of conditions across your interest area, displaying data values on the map at the reporting station’s location. We apply a station thinning algorithm to maintain a clear view of station conditions. If the station density seems sparse, zooming in will update the view with additional stations. Clicking on a station will display a popup with a Conditions tab that presents a table of the most recent observations and 24 hour graph (can be changed to 3 or 7 days in the Global Settings) for each variable, and an About tab with basic station and sensor metadata.

Data filtering and selection

The default display is real-time temperature observations across all public networks. Using the Explorer menu pane you can quickly adjust the display by changing variables, time, and filter to specific networks of interest with just a few clicks.


Selecting the active variable from the menu pane allows you to choose from the following list:

  • Air Temperature

  • Dew point temp.

  • Relative humidity

  • Sea level pressure

  • Winds speed and direction

  • PM2.5

  • Station pressure

  • Voltage

  • Precipitation: 1hr

  • Precipitation: 6hr

  • Precipitation: 24hr

  • Solar radiation

Time Mode

In addition to real-time observations, you can also display a historical snapshot of data. Toggle from “Now” to “Historic” mode and select any date and time (UTC or user-local) spanning our entire period of record (1996). All the data is equally accessible.

Network Selection

In addition to mapping observations by variable and timestamp, you can also filter by network. By default, all networks are shown, however you have the ability to chose the type of networks you’d like to see, or specify one or more networks yourself. “Use by group” filters by preselected groups that work well together or are similar in observing purpose. “Custom” allows you to select by one or more networks, you can look up networks by their long or short names given here.


The Table page displays detailed metadata and data at a single station of interest. The page provides the option to toggle between all available variable measured by the station, or groups of variables which filter the data for common use cases (e.g. Fire Weather, Air Quality). You can change the variable group in the Global Settings (view the list of variables in a group by clicking on

next to the selection dropdown). You can select a station by either clicking on one in the Explore page or clicking station on the Table navigation drawer to select from the map (with the option to filter for the current selected network). Similar to the Explore page, you can change the time period of interest in the Table navigation drawer.

The first table display basic metadata for the station, such as location, period of record, and data provider attribution. Selecting the Metadata link navigates to a more comprehensive metadata table listing nearby active stations, reported variables and their sensors metadata, and station history which details the time of all specific metadata updates. You can click Tabular data to return to the default data view.

The Summary Weather Data table provides a summary of the most recent station report along with minimum and maximum values for the current and previous days (minimum and maximum values are only displayed in the ‘Now’ time mode). If the time mode is ‘Historic’, the table will populate with the station report at the closest date time to that specified. If the station reports precipitation, precipitation accumulations over the 1, 3, 6, 24, and 48 hours leading up to the specified date/time stamp are also displayed.

Hovering over “How can I access this data?” will provide the exact Weather API query used to power a table or the link to the Data Download tool to save the data.

The Station Data table displays the station time series data over the duration specified by Global Settings ‘Duration’. Within the table, observations flagged by Synoptic’s QC processes are displayed in yellow. Hovering over the yellow flag displays the name of the QC check (more information about QC).


The Graph tab allows the user to specify a date and time ('Now' or ‘Historic’) and create a timeseries graph for up to 7 days, ending on the specified date time. To begin, click “Add New Plot”. From there, the user can choose to graph one or more variables for a single station or a single variable for up to 4 stations. Variable(s) can be selected from the pre-defined variables or searching for variable (list of available variables and their Synoptic callable names). Stations can be selected from the map by clicking on a station and can be filtered by network.

After selecting confirm, the graph will be generated. To edit a graph, clicking the pencil symbol will take you back to the initial selection page to update the graph. To download an image of the graph, you can select the three lines and choose the desired image file or view a graph full screen. Clicking, holding, and dragging on a graph, you can zoom into the graph without having to change the duration.

Only 4 graphs can be displayed at one time, whether or not they are single/multi station graphs.


After creating custom visualizations across Synoptic Data Viewer’s tabs, users can add them to their list of Favorites. While on the desired tab to save, clicking the heart symbol in the upper right corner will save a customized visualization. This will only save the selections, not the Global Settings, and only the current tab. These favorites can then be accessed clicking the blue user symbol in the upper right corner, categorized by their respective tabs.

Global Settings

As the name states, Global Settings allows the user to select how the data is represented or is able to appear across the tabs within Synoptic Data Viewer.


Toggle between timestamps appearing in UTC (GMT) or station local time. Also, the option to select between the datetime formats of the 12- or 24-hour clock for local time.


Variables units can be selected here as either Metric or English broadly, in addition to selecting units for variables types that may have 2 or more options. For example, speed can be reported as meters per second (MPS), miles per hour (MPH), kilometers per hour (KPH), and knots (KTS).


Set the duration for time series across Synoptic Data Viewer’s tabs to 1,3, or 7 days (this will update the duration set in the Graph tab as well).

Variable Group

Variables groups filter the data (in the Table tab if toggled on) based on the observation needs of common use cases. To view the list of variables in a group click on (info) next to the selection dropdown.

METAR Reports

Setting METAR Reports to all returns only the high frequency observations while official only adds hourly and special reports (applicable only to the ASOS/AWOS network).

Quality Control Mode

Allows the users to toggle on/off QC which will return flags alongside potentially erroneous values (Synoptic Data QC). There is also the ability for QC flagged values to be removed or kept. Basic, Basic + Advanced, or a custom defined set of one or more QC checks can be selected here. Basic and Advanced checks include:

Basic QC

  • SynopticLabs Range Check

  • SynopticLabs Temporal Persistence Check

  • SynopticLabs Wind Speed vs. Maximum Gusts

  • SynopticLabs Wind Speed vs. Wind Direction

  • SynopticLabs Rate Change Check

Advanced QC

  • SynopticLabs Percentile High Outlier Check

  • SynopticLabs Percentile Low Outlier Check

  • SynopticLabs Spatial Percentile Check

  • SynopticLabs Spatial Value Check

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