Thursday's Wave Low is continuing to cause me some concern & is proving troublesome to the Model Guidance. The 00Z Runs of the ICON, ARPEGE & some ECMWF Ensemble members indicate the risk of a much deeper wave depression developing over CS/SE England during the afternoon. >>





this leads to a spell of potentially very strong winds in those models over parts of coastal S/SE England before clearing into the North Sea. A very active squally cold front is going to move east during Thursday. This ALL models agree on, however the shape & extent of the upper

1/10) 1st November Morning Update #StormCiarán
The rapidly developing low is currently moving rapidly into the Eastern Atlantic around 987mbs, steady deepening occurring overnight, however it will soon move into the Left Exit region of the Powerful 200mph Jet. This will act like



(2) a giant chimney & at 300mb (5 miles up) the air will rush outward rapidly, this means that air from the surface has to rapidly take its place which will cause the pressure to drop rapidly at the surface deepening the Storm. (That is called Divergence aloft) This causes the

(1) Tuesday Evening Update on #StormCiaran. Unfortunately we now have quite high confidence in a spell of potentially very damaging winds across NW France & the Channel Islands and preparations for #StormCiaran in #JerseyCI & #GuernseyCI should be completed as soon as possible. (2) Ciaran could bring gusts over 90 & perhaps near to 100mph over the Channel Islands late on Wednesday Night & early on Thursday. Ciaran is currently SE of Newfoundland around 993mbs, currently sat under the Jet with only modest deepening. The 12Z St John's ascent analysed

(1/) 31st October AM Update on #StormCiaran. Increasingly confident about damaging winds affecting West Cornwall & Channel Islands, Coastal Sussex & Kent Kent. Remains on a knife Edge for other Southern Coastal Counties this morning.50-100Mile bounds will make a huge difference



(2) #StormCiarán is currently located S of St Johns in Newfoundland, analysed at 997mbs at 07Z. The 00Z Ascent from Caribou Maine perfectly sampled the Powerful Jet across the far NE part of North America. This was at 180Knts or 207mph.This was under analysed by both the GFS &

(1/) The Embryonic Low which will highly likely become the next name storm is now developing along a developing frontal boundary over the Ohio Valley. This Low will move East across the Atlantic where it will come under the influence of the powerful 160-170Knt (nr 200mph) Jet (2/) The low is set to deepen rapidly as it crosses the Atlantic, though there remains some uncertainty in the models with respect to when the most explosive phase of deepening will occur & how near this is to the UK. The 00Z Suite of models have backed off (thankfully) a little

(1/) There is growing support this morning from the UKMET, ICON, JMA, Canadian, ECMWF Ens, for a track for Wed/Thurs Low (which will become Storm Ciaran) for a track across the Atlantic emanating from a developing embryonic Low on a very tight Baroclinic Zone (Thermal boundary) (2/) over the NE USA. The Low moves rapidly east towards the SW Approaches, then turns NE across the UK. The ECWMF Operational is now somewhat on its own (with a few ensemble members) in turning the Low across Ireland, However the majority of the Ensemble + the UKMET, ICON, GFS

1/6 Despite a NOAA G-IV Dropsonde Mission & Multiple extra weather balloon launches over the Continental US overnight,there remains a clear split in the model guidance with the GFS & some of the GFS based Hurricane models further west than than the Euro Models (ICON, UKMET,ECMWF) 2/6 Studying the Upper Wind patter over N America over the next 3 days, a strong longwave trough over the Eastern US,extends south in both the GFS & ECMWF,but in the ECM the extension is stronger, this appears to be related to the strength of a Jet streak currently over NW Canada