Surface Weather Maps Help Page

MesoWest has been designed for use by National Weather Service meteorologists and other professionals for protection of life and property. Comments/suggestions for improvement may be sent to

The MesoWest Surface Weather Maps allow the user to display surface weather observations in a map framework. This convenient interface takes advantage of open-source interactive map plotting tools to plot observations.

If default parameters are chosen, the most recent observations within 1 hour are displayed for the chosen region. A single query to the MesoWest database collects all of the observations for a number of different variables (temperature, relative humidity, wind speed, wind direction, etc.). To reduce wait time, and to produce a cleaner display, we recommend users at first choose a small region and not select "All Networks" for options. Users can use cookies to "remember" a favorite configuration of settings. Users can also save profiles, as discussed in the MesoWest User's Guide.

The stations are plotted as filled-in circles at the location of the station with wind barbs. See this page for more information on how to read wind barbs. Remember, one full wind barb is 10 knots (5 m/s) while one half wind barb is 5 knots (2.5 m/s). Basic observations for a station can be seen by moving the mouse over a station on the map. If you click on a station, a pop-display with graphs of observational data, maximum/minimum values, and a link to the Station Interface Page are available.

The color of the station location denotes the current station quality. Black dots indicate "OK" or "N/A", orange dots indicate "Caution", and red dots indicate "Suspect". See our Data Quality Control Information page for more information.

There are many settings the user can set to change both the display itself and the observations.

Top Menu Bar: The tan menu bar at the top of the page provides a number of options including...
Show/Hide Menu: the user can show or hide the left settings panel.
Show/Hide Tables: the user can display a table on the right of the observations plotted on the map.
This table can be sorted by values by clicking on one of the column headers.
The color of the data denotes the data quality.
Search Location: the user can enter a location (city, zipcode, etc.) and the map will move to that location and plot local observations.
Active Fires: the user can display fire layers on the map (see the Fire Product Overlays help page for more information).

Data Selection (left panel): This section allows the user to choose what stations to display, what units to display, and what region to select.
Region Selection: the user has two primary options for selecting where to plot data...
Region/Zone: the user can select a defined region that is one of the following...
GCA: National Interagency Coordination Center (NICC) Geographic Coordinating Area
CWA: National Weather Service County Warning Area
FWZ: National Weather Service Fire Weather Zone
Radius: the user can define a radius to search for stations around where they click on the map. The options are...
10 miles
25 miles
50 miles
75 miles
100 miles
150 miles
200 miles (all stations for My MesoWest users, only NWS-owned stations otherwise)
300 miles (all stations for My MesoWest users, only NWS-owned stations otherwise)
450 miles (NWS-owned stations, for My MesoWest users only)
Network: The user can choose between the following for network combinations...
NWS: Displays stations that are only a part of the NWS/FAA network.
RAWS: Displays stations that are only a part of the RAWS network.
NWS and RAWS: Displays stations that are a part of either the NWS/FAA or RAWS networks.
SNOTEL: Displays stations that are only a part of the SNOTEL network.
APRSWXNET/CWOP: Displays stations that are only a part of the Citizen Weather Observing Program.
All Networks: Displays all of the stations, regardless of the network.
Units: The user can choose to plot english or metric units.
Click "Map It!" once finished to load your desired data.

Display (left panel): This section allows you to control what variables are displayed next to the stations on the map. There are two overlay options, Overlay 1 will plot to the left of the station, while Overlay 2 will plot to the right. There are many options available in the menu lists, and data will automatically display once you select an option. The "Highlight Data" option highlights the values in a white box with red lettering when checked. Finally, the "Show Table" option displays a pop-up table similar to that discussed earlier in the "Top Menu Bar" section.

Other Features (left panel): This section provides access to view archived data or to overlay image layers on top of the map.
Time Options: the user can set options to view archived data on the map by changing the following...
Date/Time: the user can alter the date and time (UTC in the format HH:MM, an example is 01:00) to view archived data.
Auto Current Time: the most recent observations will always be shown if this box is checked, uncheck to view archived data.
Reports in Last X: the user can select how far back from the given time to plot stations (useful for stations that don't report often).
Auto Refresh: the user can set how often to reload the page with the latest data.
Restrict Time Window: see the description near the bottom of the "Time Options" box on how to use this feature.

Map Options: It is possible to overlay the observations on terrain or satellite maps at this time. The terrain map is available on MesoWest courtesy of Mapbox and OpenStreetMap, while the satellite map layer is courtesy of ESRI World Imagery.

*Important Notes:

1) Some web browsers may perform better with the map than others, please feel free to contact us if you discover a problem with the map interface.
2) An option to thin observations (so less show one a larger map) is unavailable at this time. Please exercise caution when zooming out on the map as stations will become bunched and difficult to read. This may additionally slow down performance for your browser as well.
3) Pressure variables on the map interface are in a coded format.
a) For metric units, the pressure is displayed as a 3-digit number. Decimals are discarded, and only the first 3 digits are shown.
For example, 1002.3 millibars is displayed as "002", and 999.1 millibars is displayed as "999".
b) For english units, the decimal point and leading digit are removed. For example, 29.92 inches of mercury displays as "992".