Table of Contents


In this module, the two major mid-latitude cyclone models, the Norwegian cyclone model and the Shapiro-Keyser cyclone model, will be explained in detail. The intention of the module is to point out the main differences in the life cycles of cyclones of the Norwegian type and the Shapiro-Keyser (S-K) type. Special focus will be placed on the synoptic preconditions that lead to the formation of cyclones.

Finally, sting jets, which often appear in the context of Shapiro-Keyser cyclones, will be briefly introduced.

Learning objectives:

In this module, you will learn more about the major differences that characterize the classical Norwegian cyclone model and the more recent Shapiro-Keyser model, and increase your ability to differentiate them when analyzing fronts from NWP charts and in combination with satellite images. After finishing this module, you will be able to use both models to diagnose the current state of the atmosphere.


This module addresses those with a basic knowledge of cyclogenesis. It focusses particularly on forecasters who want to know more about the differences between the Norwegian and Shapiro-Keyser cyclone models.

I. Introduction

Start with a short quiz to see the challenge when making a frontal analysis of extratropical cyclones.


II. The Norwegian Cyclone Model versus the Shapiro-Keyser Cyclone Model

The Norwegian Cyclone Model versus the Shapiro-Keyser Cyclone Model Learn more about the main differences and analogies between these two cyclone models.


III. Side by side comparison of a Norwegian Cyclone (9 13 March 2019)
and a Shapiro-Keyser Cyclone (14 17 March 2019)

See two real-life examples of the two cyclone types and compare their evolution with satellite images and model fields.


IV. The Sting Jet

Learn more about Sting Jet, a phenomenon that is often involved with Shapiro-Keyser Cyclones



* TECHNICAL NOTE: For the best interactive experience throughout this module please use the most recent versions of Firefox, Google Chrome or Internet Explorer browser!