Is A Storm Coming?

The best way to find out the answer to the question "Is there a storm coming?" is to look at some weather data charts. These are really simple to understand once you know how, and the best way to predict a storm.

In this article I will be looking at some weather charts, and explaining how to read them. This is a very basic introduction to weather charts and in no time you will be able to answer the fateful question "Is there a storm coming?"

The pic shows an incoming storm that I snapped whilst on a walk. Find more of my storm pictures here.

Using Pressure Charts to Predict a Storm

Possible storms can be predicted fairly early on about a week to nine days before the event, using a pressure chart. You can track the areas of low pressure across the charts, which update every four hours. You can also track the predicted area of low pressure for as long as the chart will allow.

Of course over a week or nine days a storm can fizzle out, change it's track, or intensify. You will not get a complete picture of the storm until at least 24 hours before the event, or later. At this point the different model weather charts start to line up with each other, and become pretty accurate.


There are different models for predicting surface pressure, and weather in general, I like to use the GFS model, which seems to have a good track record for accurate predictions, Just my personal opinion. Other people have their own faves.

When you look at a surface pressure chart with regards to a storm, look for an area of low pressure, with many rings around the center. The lower the pressure, and the more rings there are, the worse the winds will be. Lots of close together rings mean high winds.

Reading The Chart

The screenshot below taken from the GFS weather radar shows a possible storm. This one is a prediction of an area of low pressure for this coming Sunday.

The red circle shows the area of low pressure 968mb. Anything under 945mb has the potential to be a
very strong widespread storm. This one has predicted wind gusts of 75mph in Scotland but moving down the country to my area the wind drops to 35mph.

The red arrow shows the tightly packed rings.

The lines that form the rings are flowing in the direction of the wind.

The same pressure chart next to the predicted wind gust chart for the same day and time. See how the wind streams follow the direction of the lines in the pressure chart.

The next chart to look at will be precipitation, this shows the amount of water in the atmosphere. The chart for Sunday shows that in my area there's not much precipitation. (use the colour code key to the side) but for Scotland some areas of heavier rain.

If you want to see where it's lightning then check out a lightning map. These awesome charts show lightning strikes in real time, you can watch the storm approach your area, and see how frequent the strikes are.

This is just a quick demo using the quickest data available. Next time we have a large storm coming up I will go into more detail as there will be more interesting signs to show on the charts.