The EZWxBrief progressive app provides the capability to see the latest surface observations for most airports as covered in the previous EZTip, but it also allows you to see the latest SIGMETs, both convective and non-convective that are issued by the Aviation Weather Center. Here's a quick reminder how you display SIGMETs on the EZMap.
First, click or tap on the Start button from anywhere in the application and select Plan a route from the Quick Start menu. This will open up the EZMap where you can now add one or more layers to the map. SIGMETs are just one of the options in the layer selector. To add the SIGMETs layer, click or tap on the Layer Selector icon in the upper-left as shown by the red arrow in the image below. Next, select the SIGMETs layer and then choose one of the attributes available within the menu. In the example below, the Convection attribute has been selected to filter out all SIGMETs except for active convective SIGMETs. Selecting All will display all SIGMET types including both convective and non-convective as well as international SIGMETs.
If you do not have an active route defined, then you will see a generic time slider at the bottom of the map. Otherwise the EZDeparture Advisor will be shown like you see below. The time on the EZDeparture Advisor will default to the time set from your previous visit to EZWxBrief unless that time is in the past. In that case, the slider will be set to the top of the next whole hour and positioned at left-most point on the slider. For example, next to the red arrow labeled (2) the current time is 1640Z, so the left-most position of the time slider in the EZDeparture Advisor will be 17Z as shown next to the red arrow labeled (3).
SIGMETs issued by the Aviation Weather Center are valid over a range of time. For convective SIGMETs this is two hours and non-convective SIGMETs are typically four hours (international SIGMET valid times vary depending on the country of origin). In order to see the active SIGMETs on the EZMap, the EZDeparture Advisor needs to be set to a time that is between the beginning and ending valid time of those SIGMETs. If you tap or click on the polygon that represents one of the SIGMETs (in this case a convective SIGMET), a tabular display will appear to show you the text associated with that SIGMET as shown above.
First, take note of the valid period of the SIGMET. In this case, the convective SIGMET is valid from 1555Z to 1755Z as shown in the text pointed to by the red arrow labeled with a (1). Next, notice the time is currently 1640Z, so that the left-most position of the slider is automatically set to 17Z. Given that this convective SIGMET is valid until 1755Z, it is displayed on the EZMap. If you were to click (or press) and drag the time to the right to 18Z or later, this convective SIGMET will disappear from the map since it is no longer valid at those times.
If you select the SIGMETs layer along with one or more of the attributes for that layer and there are no SIGMETs active at that time, as shown above you will get a momentary informational message in the upper-right corner of the map that will say, No SIGMETs Displayed to make you aware there are no SIGMETs active during the time selected on the EZDeparture Advisor.
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Most pilots are weatherwise, but some are otherwise™
Dr. Scott Dennstaedt
Weather Systems Engineer
CFI & former NWS meteorologist