The 00z GFS operational run this morning predicts that an intense low
will run eastwards across the middle of the British Isles Wed/Thu next
week. However, if you look at the ensemble thumbnails at


http://wxcharts.eu/?model=gefs&regio...nel_mslp& run
=00&step=120


you will see that the range of possibilities is extremely diverse. UKMO
and ECMWF also show some sort of development on their operational runs
but these GFS thumbnails suggest that the all-important detail cannot
yet be predicted to any useful level of reliability. It's still all up
for grabs and it certainly looks like being a much more complicated
evolution than the operational runs have been predicting for the past
few days.

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
https://peakdistrictweather.org
Twitter: @TideswellWeathr

On 13/01/2018 10:30, Norman Lynagh wrote:
The 00z GFS operational run this morning predicts that an intense low
will run eastwards across the middle of the British Isles Wed/Thu next
week. However, if you look at the ensemble thumbnails at


http://wxcharts.eu/?model=gefs&regio...nel_mslp& run
=00&step=120


you will see that the range of possibilities is extremely diverse. UKMO
and ECMWF also show some sort of development on their operational runs
but these GFS thumbnails suggest that the all-important detail cannot
yet be predicted to any useful level of reliability. It's still all up
for grabs and it certainly looks like being a much more complicated
evolution than the operational runs have been predicting for the past
few days.


One moment at the Grand Banks, then 24 hours later over England.
The GFS plots i look at have the "storm motion" of the enhanced wind
regime in the SE quadrant below the low centre, off the scale, ie above
90mph, the winds themselves, while still over water sustained 60mph.
Yesterday GFS had worst winds for south England, swapped with MetO
today, MetO now going for southern England.
Otherwise generally divergent model outputs is not a good sign, ie sign
of instability in big-data cogitations?

On Saturday, 13 January 2018 10:30:46 UTC, Norman Lynagh wrote:

you will see that the range of possibilities is extremely diverse. UKMO
and ECMWF also show some sort of development on their operational runs
but these GFS thumbnails suggest that the all-important detail cannot
yet be predicted to any useful level of reliability. It's still all up
for grabs and it certainly looks like being a much more complicated
evolution than the operational runs have been predicting for the past
few days.

EC operational diagnoses inland gusts to 80 mph in N England from this low, so interesting stuff.

Richard

On 13/01/2018 11:19, Richard Dixon wrote:
On Saturday, 13 January 2018 10:30:46 UTC, Norman Lynagh wrote:

you will see that the range of possibilities is extremely diverse. UKMO
and ECMWF also show some sort of development on their operational runs
but these GFS thumbnails suggest that the all-important detail cannot
yet be predicted to any useful level of reliability. It's still all up
for grabs and it certainly looks like being a much more complicated
evolution than the operational runs have been predicting for the past
few days.

EC operational diagnoses inland gusts to 80 mph in N England from this low, so interesting stuff.

Richard


GFS 06Z run, has 75mph gusts for London early hours 18 Jan, with
whatever else is thrown into the mix.