Saturday, January 26, 2008

Tuesday storm

It's been long time most of the numerical weather predications are forecasting a huge monster storm will stick towards Jordan and the Middle East. But as we are getting close for the zero hour of the storm, I still can see some dramatic changes between 2 main models, which are GFS and ECMWF.
In this winter season, ECMWF achieved amazing results in it's medium and short range forecasts, while GFS for this season is having a lack of accuracy, this is makes me, or let me say forces me, that I have to follow ECMWF in my forecast for this storm. On the other hand, I depended on GFS in the past 3 years in forecasting any powerful storm and it was accurate.
Tonight 12z updates will be the logic. I am afraid that GFS will have dramatic changes that it will follow ECMWF, thus will makes most of the forecasters to become pessimistic after a long time of optimistic forecast! But if GFS stays at night-update the same as now, we will be having a problem! Yes a problem in forecasting when the snow will start and where it will fall and other factors.
Might you ask me, why ECMWF will not follow GFS?
It's a logic question, and my answers, is just look at the GFS00z and GFS06z ensembles maps, and see how many members are following ECMWF.
Finally, I will summarize the weather for Monday and Tuesday, relying on ECMWF and UKMET models, without relying on GFS:
On Monday, a very cold polar air will penetrate to eastern Mediterranean, the will led to forming a very deep (classic) Cyprus low pressure over northern Cyprus, with center of 996mb, this will cause starting from Monday noon time, a very strong winds, and it will increase in speed by time, to reach at night gale force winds. I expect the low pressure will start to move towards North West Syria, and this will led to storm force winds will pass the 110 Km\Hr. Rain will start Monday Evening over northern areas, and will gradually spread to central areas. The rain will get stronger at night and it will be heavy with strong thunderstorms and hail showers, simply the weather will turn at night to stormy.
By Tuesday morning, rain will be falling heavily over most parts of northern and central areas, accompanied by strong thunderstorms, and strong hail showers, and storm force winds (110 km\hr). I believe that areas higher than 1000 meters could see snow showers during morning, but I don't think that it will be accumulative. Towards afternoon, rain will gradually turn to heavy snow over areas above 1000 meters, and will get stronger afternoon, and I expect that areas higher than 800meters will see snow also. Snow will continue to Wednesday noon time, over areas higher than 800meters, and for note, areas above 650meters could see sleet. For here my forecast will end, and I will be back tonight to discuss the 12z updates for all models.
Mohammad

2 comments:

Unknown said...

Hi Mohammad,
How Are you?

Thank you for your interesting post.

I live in Eilat (across from Aqaba).

Do you think there is a chance for snow on the mountains in my area, this week?

Thanks
omer

Hisham said...

Dear Mohammad, which tuesday (date) are you talking about?