Drawing OSA charts. Once Synops have been downloaded and ingested. Open Nelant Basic.

Click the OSA button.

Click the select button on the pop menu. Check the latest model is selected click ‘OK’. Then click ‘OK’ again on previous Menu.

De-select Model/ Analysis difference. Select Observations. Change the Field smoothing from Disabled to Moderate Select ‘Layer Editor tab on side.

First highlight ‘land’ by clicking on it. Then select ‘brown outline’, ‘orography’ then ‘light-green’.

Then add the model layers you require, by going Into ‘Presets’, ‘Layers’, ‘HMOPS’ and selecting the layers you want.

Once you have added the model layers you require, you need to select the chart time by going into the SigWx editor menu.

The SIGWX Editor tab opens The SIGWX Editor tab opens. This has all the tools needed to draw the relevant features on the chart.

To select the type of front To select the type of front. First click on the cold front picture, then on the drop-down menu select the type of front.

To draw the front, left click on the chart tracing the line of the required front left clicking where points are needed. Once finished drawing the front double click to finish.

If you want to change or move the front If you want to change or move the front. Hold down the ‘SHIFT’ key and click on the front. All the points will be highlighted, you can move points by dragging them or move the whole front by clicking on the front away from the point and dragging. Once you have finished editing move mouse away from front and right click to de-select.

To zoom in on a area. Hold the ‘CTRL’ button, draw a box around the area you want. To go back to the original map area. Right click on map and select Zoom 100%

If you have drawn the wrong type of front, once the front has been highlighted, using the drop down menu, change it to what is needed. 2. If the front has been drawn the wrong way round, this button will flip it. 1. 3. This button will delete the highlighted front. 4. If you want to clear all fronts on screen. 3. 4. 2.

If you want to hide any of the layers. First go to the Layer Editor. Then Click on the ‘eye’ on the layer you don’t want to be displayed, a red circle with a cross will appear when hidden.

Once you are happy with the chart, Save the fronts by clicking the ‘Save’ button on the SIGWX Editor Tab.

After saving the fronts. De-select all layers not required to be shown on final product. Select the Feature Database Source (SigWx) from the drop-down menu.

The Feature Database Source (SigWx) layer will appear on the Layer Editor Tab. Double click on this. On the pop-up menu, check that the chart name in the products box is the same as you selected at the beginning. Then click OK.

If saved properly, the fronts will appear on the Feature Database Source (SigWx) layer. And the fronts on the chart will be shown twice.

Once happy to export as an image. File> Export as....> Image.

Make sure the format is JPEG. And the export frame is selected as current. In directory, choose where you want to save the chart. And in file name, give the chart a relevant name. Make sure that the automatic file name extension in ticked.

Finished products should look like this.