Warm Front Band

• Cloud Structure In Satellite Images
• Meteorological Physical Background
• Key Parameters
• Typical Appearance In Vertical Cross Sections
• Weather Events
• References
•  
• Special Investigations:
  • • Different Kinds Of Warm Front Development

Weather Events

Warm front bands are associated with multi-layered cloud structures, with clearances in the cloud-free regions in the warm sector. Precipitation can exist well ahead of the surface front, until just after the passage of the front.

Parameter	Description
Precipitation	Rain bands typically 50 kilometres wide and a few hundred kilometres long, usually orientated with a small deviation in angle to the surface front Slight, moderate or heavy precipitation ahead of the surface front In winter, snow exists ahead of surface front. Freezing rain (drizzle) is also possible. After the front passes small areas of drizzle (light snow in winter) can occur
Temperature	Rises after the passage of the front
Wind (incl. gusts)	Veering of the wind as the front passes Sometimes in the warm sector, winds will increase and become more gusty
Other relevant information	Precipitation areas move faster than the surface front (they are also embedded in the warm conveyor belt). Sometimes moderate to severe icing occurs ahead of surface front In wintertime, the warm sector has a high risk of fog In the warm sector, low level turbulence is also possible In summer, thunder is possible, with the highest risk on the warm side of the front Apart from fog in the winter and spring seasons, the warm sector is typically a dry area with clear patches of cloud-free regions.

The case from 17 September 2019 at 12 UTC exists mostly over the sea but there are reports from some inhabited Islands which demonstrate the weather situation.

Legend:
17 September 2019 at 12UTC: IR + synoptic measurements (above) + probability of moderate rain (Precipitting clouds PC - NWCSAF).
Note: for a larger SYNOP image click this link.

There is no precipitation report from the existing weather stations (which are along the leading edge) but some spots with higher precipitation probabilities are at the rearward edge.

17 September 2019at 12 UTC
1st row: Cloud Type (CT NWCSAF) (above) + Cloud Top Height (CTTH - NWCSAF) (below); 2nd row: Convective Rainfall Rate (CRR NWCSAF) (above) + Radar intensities from Opera radar system (below).

For identifying values for Cloud type (CT), Cloud type height (CTTH), precipitating clouds (PC), and Opera radar for any pixel in the images look into the legends. (link).