Daily Report 2016 09 19

Flight Plans for the next days

A flight is planned for upcoming Wednesday to capture a WCB outflow over Iceland with Falcon, and WCB outflow and ascent with HALO. HALO and FALCON will fly synchronized. Upcoming Friday there is the possibility for capturing the inflow of a WCB with HALO in the NOTAM region (possible coordination with FAAM). On Saturday another coordinated HALO/FALCON mission is planned to capture the outflow of this WCB between Iceland and Norway. The slides of the Planning Meeting as well as the Planning Summary can be found at the bottom of the page.

Weather Summary

A quasi-stationary trough is located in the Greenland-Iceland region and dominates the large-scale flow during the next days. Upstream of this trough polar air penetrates southward over the Labrador Sea. At the same time a warm-moist air mass of (sub-)tropcial origin penetrates poleward. At the boundary of these airmasses a marked frontal zone establishes across the North Atlantic, stretching from Newfoundland to Iceland.

Along this front cyclones and WCBs form repeatedly during the next 10 days. A first cyclone and accompanying WCB reaches Iceland on Wednesday, 21 September; two days later a second system passes Iceland slightly further eastward. This constitutes perfect conditions for the observation of WCB ascent and outflow regions during the next 5 days.

On the longer time range sytems of interest are the potential extratropical transition (ET) of TC Karl and an emerging downstream cyclone during Sunday - Wednesday next week (25-28 September). Both are accompanied with an atmospheric river and intensive moisture transport towards the UK, Northern, and Central Europe with high risk of large-scale heavy precipitation early next week. The intensity and exact timing of TC Karl undergoing ET, and the downstream cyclone are still uncertain, whereas there is less uncertainty about their track towards Europe, if they occur. In terms of the large-scale conditions, the flow tends to become more zonal towards the end of this week.

Planning Summary

The presentation of the Flight Planning meeting as well as the Planning Summary can be found at the bottom of the page

Instrument Summary