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Note
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Task 1: Mean-sea-level pressure & wind gust

Right-click the mouse button on the 'an_1x1.mv' icon and select the 'Visualise' menu item (see figure right)

After a few seconds, this will generate a map showing two parameters: mean-sea-level pressure (MSLP) and 3hrly max wind-gust at 10m (wgust10).

Use the play button to animate the map and follow the development and track of the storm.

You can use the 'Speed' menu to change the animation speed (each frame is every 3 hours).

Task 2: Geographical region

Right-click the mouse button on the 'an_1x1.mv' icon and select the 'Edit' menu item (see figure right).

An edit window appears that shows a number of lines of 'Metview macro' code. During these exercises you can change some of these to alter the parameters and plot types.

Panel
bgColorwhite
titleBGColorlightlightgrey
titleTwo map types are available covering a different area

With mapType=0, the map will cover a smaller geographical area centred on the UK.

With mapType=1, the map will cover most of the North Atlantic

Change, mapType=0   to   mapType=1   then click the play button at the top of the window (please ask if you are not sure).

Animate the storm on this smaller geographical map.

Task 3: Plot wind fields

Change the fields plotted to include the wind arrows.

Make sure you have the Edit window showing.

Code Block
languagebash
titleAdd wind arrows to the plot:
#Define plot list (min 1 - max 4)
plot1=["mslp","wgust10","wind10"]

As above, click the play button and then animate the map that appears. You might also want to change the mapType back to 'mapType=1' to show the larger geographical area.

Discuss the storm development and behaviour with your colleagues & team members.

 

That completes the first exercise.

If time

  • You are encouraged to explore Explore the storm development and passage using the other parameters available on other pressure levels.
  • More explanation of how to use the Metview macro icons to alter the fields plotted are shown below.

If you prefer to see multiple plots per page rather than overlay them, please use the an_2x2.mv macro.

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Panel

For this exercise, you will use the metview icons in the row labelled 'Oper forecast' as shown above.

oper_rmse.mv                                   : this plots the root-mean-square-error growth curves for the operational HRES forecast for the different lead times.

oper_1x1.mv & oper_2x2.mv    : these work in a similar way to the same icons used in the previous task where parameters from a single lead time can be plotted.

oper_to_an_runs.mv                         : this plots the same parameter from the different forecasts for the same verifying time. Use this to understand how the forecasts differed, particularly for the later forecasts closer to the event.

oper_to_an_diff.mv                           : this plots a single parameter as a difference between the operational HIRES forecast and the ECMWF analysis. Use this to understand the forecast errors from the different lead times.

 

Parameters & map appearance. These macros have the same choice of parameters to plot and same choice of mapType, either the Atlantic sector or over Europe.

Key questions

Notepanel
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titleKey questions
  1. How does the HRES forecast compare to analysis and observations?
  2. Was it a good or bad forecast? Why?
  3. How does the forecast change with the different lead times?

Getting started

Note
iconfalsetitleTeam: Getting started

Each team should look at the forecast from all 4 starting dates and each team member should see the RMSE curves.

Start by looking at the RMS error curves for the 4 different starting dates using MSLP (mean-sea-level pressure) and wind parameters (wind gust at 10m: WGUST10 and wind-speed at 850hPa : SPEED850) and the two geographical regions. Use the oper_rmse.mv icon for this.

As a team, discuss what plots & parameters to use to address the questions above given what you see in the error growth curves.

Then look at the difference between forecast and analysis to understand the error in the forecast, particularly the starting formation and final error.

Team members can look at particular dates and choose particular variables for team discussion.

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