Second Scenario Won!

Hello All,

sorry for not updating, just I am too busy.

I want to inform, that all computer models gatherd to show that the second scenario will take place on Thursday for the arctic blast.

So no snow, just wide frost and severe icing mostly everywhere on Thursday with very low temperatures.

Also, we could see some stations in eastern Jordan reporting record temperatures during Thursday-Friday night.

There is a low chance for some light (localized) snow on Wednesday evening and night over southern high Mountains, and eastern desert.

I will be back tomorrow for more specifications. Stay Tuned

Good Night,
Mohammed

Entering Week of 27th...

Good Evening to all,

I talked before approximately half a month about a possibility of having something special in the week of 27th of December for this year.

So we entered today officially the week of 27th of December which will extend to 2/1/2009 in the New Year (Friday).

Weather wise, there will be some rain events this week on Monday, Tuesday and Wednesday possibly will concentrate at the northern parts of the kingdom, perhaps some showers will succeed in spreading to the central areas, but what after that?


(Please click on the image above and keep it in mind while reading the following)
After that actually, a very cold arctic (continental) air mass will be pushed towards Turkey by late Tuesday, and continental means that this arctic air mass will be very cold, but also very dry, that means no actual snow accompanying it, but the computer numerical models maps are showing somehow 2 scenarios may this arctic air mass select, the first scenario that some computer models are showing that this arctic air mass sweep deep to the eastern Mediterranean sea, which means gaining high amounts of relative humidity and moisture, and then enters to Jordan by Thursday, and this scenario to be honest will cause snowfall over wide areas, but there is a second scenario suggested which is more possible at the time being by the computer models, that the arctic air mass sweep through Syria and eastern Syria, and continue to be a dry air mass, and this will lead to a very strong frost wave covering much parts of the kingdom with partly cloudy to mostly sunny weather, and temperatures may not pass/exceed 5 degrees as maximum in Amman on Thursday, and on night hours we could see some stations reporting -5 and -7 !!

We will keep monitoring the models and see, and I'll keep you updated.

Chao for now,
Mohammed Al-Shaker

Frosty Nights Ahead, and what about 27th December?

Good Evening,
A very cold arctic air will be pushed late today towards northern area of Iran, as the Siberian high pressure will be deepening towards northern Eurasia early on Tuesday. This arctic cold air will spread quickly to Iran, Iraq, Kuwait, northern and central Saudi and deserts of Jordan and Syria as well. This will cause a drastic drop on the temperatures during night hours, and possibly wide area frost, and temperatures will reach by -6c over some deserted parts of eastern Jordan.

I believe of the risk of this wave! Yes Wednesday into Thursday night, there will be a new injection of cold arctic air spreading to northern Saudi and eastern Syria/Jordan, with possibility for a very low temperatures, and very wide frost, with high possibility for reaching northern Jordan Valley! Again, as last year, frost is threatening us! I think that all because of returning La-Nina.


So, please be aware of this cold wave which will possible leave us by Saturday, as the pattern will drastically change.


What About 27th December?

My colleague Ayman, talked early this week about a new pattern. Actually we are chasing now the birth of cold trough establishing maybe over central Europe, or perhaps Eastern Europe. Models start to show signals that something could be "major" will form as a result of a strong ridging will dominate western Europe, and may extend to north-west Europe. As usual, very difference scenarios are found in the models and at least that there is still 10 days left, but what about 27th December story.

Actually, there isn't any forecaster in the world can predict the exact day of a storm before 12 days, but what am talking about, is that the week beginning of 27th December (27th December to 2/1/2009), is carrying a very high potential for having a strong low pressure system could pull arctic wave to the Middle East, and also pull the snow!


I will discuss in my post this issue, by mixing experimental methods together with real-time forecasts. (Please keep in mind the picture down below)

Here we go, 3 reasons are forced me to set my target 27th December, the first reason, as you can notice through the map, that ECMWF mainly storm track was on 00z&12z runs on 15/12/2008 is moving South-east all the way from north-west Europe, resulting Jet stream path way as you can see the blue one. Second reason, is the California effect that Ayman talked about in the previous post.
From my own experiment, some waves that hit the western USA coast and especially California need around 10 days to establish a new pattern in Europe led to a wave hitting us, and from the forecast 17th December an arctic wave will hit western USA coast, so 17+10= 27th December!
Also the blue jet stream of ECMWF has the same path way I think with the California effect.

Third reason is the analogs, JordanWeather has some analogs years, they were used in our seasonal forecast, 2 Analogs years, was being and still monitored specifically as they are having the same patterns like this year since November. The both analogs suggested jet stream path way similar to what we are talking about, and in the same period of 25-31/12/2008, you can notice that through the map above the path ways. The green and red streams are presenting the both analogs.

So?!

The conclusion is carrying an "Experimental method" forecast, as you can see the map down here; I put 3 possible tracks for the Jet Stream between 25 and 31 December. I believe that we are needing rain urgently as the season average percentage is dropping quickly, so I am not talking about snow defiantly, I am talking about breaking down the relative drought period, but also I can say that the 35% percent Jet Stream path way is enough for snow. What we have now is to wait what will happen, and to pray for rain as soon as possible.

Good Bye,
Mohammed Al-Shaker

Long Range Outlook

Good evening,

Today is the day for change according to"well known" two global numerical models; GFS and UKMET, and as said " 1000 miles journey begins in step! ", it is really an 1000 miles journey when the models start to talk about upcoming storm at least in the medium range, especially when it is the first in this winter and after a period of RELATIVE drought...

This expected system is driven by a huge area of high pressure that will situate over much of western and central Europe WITH important extension to northern Africa (Algeria and Tunisia) caused by a RELATIVELY deep and "slow moving" area of low pressure situated over S.W Morocco and Canary islands..

This will "hopefully" lead to a deep slow area of low pressure that will situate over the eastern Mideterranean, and will bring " a very welcomed" heavy rains to us..

This is the pattern that GEFS ensembles maps predicted throw many updates in different days, and myself imagined that pattern also, also there is a positive thing regarding that, which is, the monster storm which will affect the whole Western US coast, from Washington state in the north till California in the south, also throw Ohaio, Colorado, Idaho, and even Nevada.

*** P.S :- there is a semi-proven scientific rule says that "when the south western areas of the US is affected by a storm, 15 days* later we will be affected by same strength of the previous storm.

* 15 days :- from day zero upto 15th day

Now we are patientlessly waiting the ECMWF update of 12z 14/12/08, which is the strongest of all the Global Numerical Weather models for our region and many regions worldwide, that will determine the fate of the upcoming storm, NOT exactly determines but adds a very welcomed surplus to our favorite scenario ..

Thank you for ur reading ..

see u later this week..

Ayman Sawalha

JordanWeather Longrange weather Forecaster

Easterly Continue..

Good Evening,

A strong high pressure (Siberian) is situating over Northern Iran, sending Easterly very cold winds to the Middle East. Temperatures as maximum didn't pass 14c in Amman today Thursday. Also some strong gusts blow today over the deserted areas of Jordan caused blowing dust and low visibility.


By tonight, temperatures will drop down to sub-zero and there will be risk of frost formation over many areas.


Also tomorrow, easterly winds will continue and temperatures won't pass 15c as maximum in Amman, while next night, will be dramatic cold with temperatures, may drop to below-zero especially in the desert and eastern plains. There will be serious risk of frost formation in those areas.


A very deep area of low pressure centering to the west of Italy, causing gale-force winds over north-east Libya. Benghazi airport reports late today that the visibility is just 50 meters!! With winds more than 90 KM/Hr, and under thick dust storm. Through satellite images, we can notice that there is a thick line of dust storm moving northward towards Crete and southern Greece.


I think this low will move east/north-east by Saturday morning, and far edge of the warm front will pass over Jordan on Saturday, causing hazy conditions, and some cooler/humid air will penetrate during night behind this front, will open the window for some local rain showers over northern regions.


Stay tuned for medium-range outlook tonight,


Chao for now

Moh'd

Mohammed Al-Shaker

JordanWeather Admin

Private Weather Forecaster

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

Saturday Low...Next week Storm

Good Evening,

Most of the models are showing that on Saturday (26-jan-2008), there will be a trough, that might bring local showers over most parts of the country. Signals shows that the most rainfall will be afternoon on Saturday, with some heavy localized spots.

I believe that some areas above 1000 meters could see some snow showers on Saturday, but I think that the accumulation of this snow will be nothing, while areas above 1200 meters such as Ras Muneef in Ajloun, and Al-Shera Mountains in the south, could see accumulative snow on Saturday.

Into Saturday night and Sunday morning, very cold air will penetrate into the regions, which will drop the temperature at night in some areas below -3c, and I think that wild frost will form.

Many people are saying about a storm next week! Next week, and to be more accurate, on Tuesday there will be a deep low centering over North-West Cyprus, this low happened as result of penetrating of polar cold air directly to the Eastern Mediterranean. The kind of the air will be "polar maritime" which bring cold temperatures with high humidity, this will led to high precipitation during the affect of low.

I will talk tomorrow about the next week storm, as the computer models will be more logic, accurte, and similar to each other.

Happy weekend

Mohammad Shacker

Private Weather Forecaster

www.jordanweather.net