Here is the daily forecast for the UAE for Jan 20-24 which will be updated frequently.

Friday Jan 20, 2012:

Starting sunny, then becoming mostly cloudy during the day and evening hours over Qatar, Bahrain, and the UAE. chance of rain over northern UAE during the evening hours. This cloud cover is expected to enter Gulf of Oman by Saturday, where it will develop into a cold front with impact over Gulf of Oman and Pakistan. To read more about the regional weather, click here. By late Friday, cooler northwesterly winds will reach northern Arabia inlcuding Kuwait and northern KSA.

Rain Radar images of the rain showers over UAE during late hours of Friday Jan 20 and early hours of Saturday Jan 21.

Saturday Jan 21, 2012:

AM showers. Clouds to clear by mid-day, becoming windy, significantly cooler, dusty over the gulf including the UAE. Becoming very windy later during the day over the Arabian Gulf and the UAE, especially northern UAE. Very rough sea conditions. Winds in northern UAE might exceed 50 km/hr especially cities from Dubai and northward, and along the east coast as well such as Fujairah where winds descending mountains gain further speed. Much cooler across the gulf countries.

Sunday Jan 22, 2012:

Winds to subside down, but remaining breezy. Cooler weather during the day. In the UAE daytime temperatures will be in late teens, around 5 degrees below normal. Sunday night will be cold over interior areas. Due to interaction of cooler winds over relatively warmer waters of the gulf, some isolated spotty coastal shower is possible as low-level clouds cover the country.

Interaction of cooler air above relatively warmer water of the gulf caused low-level clouds that covered UAE skies on Sunday Jan 22.

Monday Jan 23, 2012:

Remaining cooler than normal. Chance of showers over the UAE coastlines of the Arabian Gulf, mainly over northern UAE. Gulf of Oman and Pakistan to receive more rain.

Tuesday Jan 24, 2012:

Clearing, becoming sunny, breezy, and remaining cooler than normal.

Synoptic weather:

After delivering rain to parts of the Mediterranean and northten Egypt, A mid-level low pressure is expected to move eastward towards southwestern Asian countries of Iran and afghanistan. With surface lows and fronts forming ahead and eastward of the upper lows, rain will fall over Iraq, Iran, then afghanistan, and Pakistan , with a cold front developing over the Gulf of Oman, northern Arabian Sea, southwestern Pakistan by Saturday Jan 21. Colder air along with a surface high will take over westward of the cold front, impacting much of the Arabian Peninsulua.

Colder Air Pushes Through:

Colder air will start making its way to the region by late Friday as windier conditions prevail , and it will be coldest in northern Arabia. Saturday and Sunday Jan 21-22 will be the coolest as daytime temperatures will fall 4-8 degrees below normal. Subsequent days will continue to be below normal, but less extreme. Kuwait and Riyadh daytime temperature on Saturday/Sunday will struggle to go above 12c with nights being quite chilly, possibly going below to -5 degrees. Bahrain and Qatar daytime temperatures will fall to mid-teens with some gusty winds on Saturday. In the UAE, daytime temperatures will be between 17-21 but with very windy conditions, and Muscat to be in early 20s.

A Lot of Winds For Some:

The Arabian Gulf will be the scene of very strong winds on Saturday with very rough sea conditions. Offshore winds will easily go beyond 60 Km/hr. UAE cities will be less extreme, but still gusty winds will blow over the northern coastlines. Winds will be between 40-50 km/hr with occasional gusts to above 50 km/hr. One area of concern is the east coast of the UAE where winds might gust beyond 60 km/hr. Open areas in northern UAE will be prone to localized dust, but coastal areas will experience fresh strong cool winds blowing from the sea. Winds will make it feel even cooler.

Unusual rain areas:

Southwest Pakistan, northern Arabian Sea, and Gulf of Oman will be under the influence of thunderstorms and rain on Saturday Jan 21.

Chance of showers for the UAE:

Small chance isolated rain showers over UAE coastlines between Saturday and Sunday. But the chance increases by Monday as a an upper air trough dives southward over the gulf, bringing some showers to northern UAE.

A new tropical storm has formed over SE Arabian Sea. It will track NW during the next 3 days. When the storm reaches northern parts of the Arabian Sea, it is expected to weaken due to high wind shear and lower sea surface temperature. Yet, impacts over Arabian Sea countries can’t be ruled as of now. Stay tuned for more updates.

Water Vapor Satellite image shows the storm forming over SE Arabian Sea.

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A fresh tropical system has formed in central Arabian Sea. it has reached tropical storm status. Easten coast of Oman is expected to get some light to moderate rainfall from this tropical low during the next 2-4 days. Some impact might reach SE Pakistan, which needs to keep an eye for any changing storm track.

Northern Oman has just received some thundershowers from the Arabian Gulf cold front. And one week back much of coastal oman had to deal with tropical storm Keila, which dumped a lot of rain and killed 14.

Infrared satellite image of the tropical storm on Nov 8, 2011.

Infrared Satellite image Nov 6, 2011. A fresh tropical system can be seen in the Arabian Sea.

Rain Radar as of 3:50AM GMT on Nov 7. Showers and some thunderstorms can be seen over the Arabian Gulf, UAE, and Qatar.

The weather has really cooled down over Kuwait and parts of Saudi Arabia with daytime temperatures in mid 20s.

After some rain over the Mediterranean, a developing mid-level low over SW Asia will help cause rain over Iraq from Firday to Sunday and Iran for the next 4-5 days. A weak cold front will develop over the Arabian Gulf. It will cause scattered thundershowers over Kuwait on Saturday and Sunday. The front is expected to slide southeastward over the Gulf, bringing the first rain of the cool season in the form of scattered thundershowers to coastal Saudi Arabia, Qatar, and Bahrain. Some showers might reach the UAE and Oman on Monday and Tuesday. A few thundershowers might bring gusty winds. Significant cooling in Kuwait and Saudi Arabia, with mild weather over the Arabian Gulf. Sea conditions will also get rough due to wind conditions behind the front.

Lightning strikes near Bahrain at 8 PM GMT on Nov 6, 2011.

Satellite image of Nov 5, 2011. Rain shower can already be seen over Kuwait and Saudi Arabia borders. This is the main boundary area that is expected to develop into a cold front.

Weather-wise, the behavior of this tropical storm was not typical. Usually, tropical storms and cyclones pass by Oman in a span of 24 hours. But Keila stalled off the Oman coast for several days, something that increases the risk of persistent rainfall, leading to floods. Keila stalled due to weak steering currents which help direct storm movement. Most of Keila’s heavy rain was offshore, and only part of it reached SE Oman (see below map). Yet it managed to pull large tropical moisture to northern Oman as well.

Arabian Sea tropical storm Keila has been dumping exceesive rain over coastal Oman. Below image from NASA TRMM site shows accumulated rain up to 9 GMT on Nov 3, 2011. We can see most coastal areas receiving around 50mm, with some areas exceeding 100mm and well into 300mm of rain over SE Oman! Some rain also reached Gulf of Oman.

7-day Accumulated rainfall ending at 9GMT on Nov 3, 2011. See the extreme rainfall over SE Oman.

These are extreme amounts and are likely to be associated with deep convective thunderstorm clouds embedded with this tropical storm. Some gusty winds have been recorded as well. With the depression lingering offshore for at least 2 more days, rainfall amounts quickly rose up, reached northeastern Oman near Muscat, but focused more around the low’s centre near SE Oman. Even as the low starts to disorganize and weaken in 72 hours, abundant left-over moisture will ensure daily scattered to isolated thunderstorms for a few more days.

Rainfall:

Rainfall exceeded 40mm over Masirah island. Other areas received between 5 – 30 mm of rain. With rain continuing for a few more days, several areas of coastal Oman might reach 50mm of rain.

Impact over Oman mainly:

Eastern coasts of Oman and possibly northeastern coast of Yemen are expected to receive some showers and over several periods between Sunday and Thursday. Showers could reach northerneastern Oman coasts. Other interior areas will experience cloudy weather. There will also be some clouds over parts of the UAE, but no rain is likely. And the Hajar mountains might receive some isolated afternoon showers as well.

Rain not part of the “cool” season

While these showers over Oman are arriving in end of October and early November, they are not the first rain of the cool season. It is part of the tropical activity of the Arabian Sea which goes through 2 windows of tropical activity. The first is in May and June, which produced violent cyclones in the past few years. The second is between October and November. The current low pressure is weak compared to tropical standards. But, it is expected to deliver much needed rain to Oman coastlines.

Where next?

There remains some uncertainty to the future behaviour of the low pressure. But most likely, it stall off the Omani coasts for 2-3 days, resulting in some prolonged rainfall over coastal Oman. Stay tuned for updates.

Infrared Satellite image shows convective clouds of the tropical low impacting Oman. Oct 31, 2011.

Infrared satellite image Oct 30 shows the low pressure getting closer to Oman.

Water Vapor image of the Arabian Sea Low. Oct 28, 2011.

Tropical storm 01A is has weakened to a depression. It is expected to dissipate during the next 24-48 hours off the northwest coast of India after delivering some rain and winds there.

Update 7 AM June 12th, 2011:

Tropical storm 01A is affecting NW India with winds and rain. Centre of the storm remains offshore. Movement NNW. Winds have increased during the last 12 hours.

Update 5 PM June 11th, 2011:

Now we have tropical storm 01A based on JTWC classification. The first tropical storm of the North Idian Ocean in 2011 after the depression has gained strength with winds of 35 knots around its LLCC. Initial expected movement towards NNW towards India.

Update 1 PM June 11th, 2011:

The depression has started showing more convection surrounding the LLCC, after days of convection located westward of the LLCC. This is a positive sign even though dry air is still surrounding it from the north. Yet the depression remains close to the Indian subcontinent after moving northeastward.

85-91 GHz brightness temperatures show location of deep convective clouds as of 5:30Z June 11, 2011.

Update 10 PM June 10th, 2011:

The disturbance is weakening. Any future development is still possible. More updates later.

Update 10 AM June 10th, 2011:

The disturbance has not been able to intensify further during the last 24 hours. It has helped enhance the wet Indian monsoon. Future development remains unlikely. Please don’t believe rumors of an upcoming storm.

Update 4 AM June 9th, 2011:

The JTWC issued an advisory about the higher probability of a development of a tropical storm within the next 24 hours. Winds around 30 knots just on the verge of becoming a tropical storm.
The tropical depression has now shown marked improvement although convection remains confined to the southwest of LLCC. It looks more likely than before that we could have a named storm in the Arabian sea if concoction wraps nicely around an exposed LLCC especially as wind shear is favorable along with good divergence aloft.

Update 1 PM June 8th, 2011:

The tropical depression has improved and become more concentric. but it remains weak and could dissipate. However, the chance of further development exists during the next 24 hours.

Update 10 PM June 6th, 2011:

The disturbance has not shown improvements. PLEASE DON’T BELIEVE RUMORS of an upcoming storm.

Update 5 AM June 6th, 2011:

The tropical disturbance (possibly depression) has shown improved convection and sea level pressure has reduced with improved LLCC. More updates later

Update 3 PM June 5th, 2011:

There is no tropical system as of now. Please avoid believeing rumours. And the chance of tropical development remains low for the next 24 hours. The disturbance still lacks organization and has not shown marked improvement. It is located close to land. Within the next 24-48 hours it will either dissipate or organize further. Don’t believe rumours as of now.

Update 11 PM June 4th, 2011:

The Joint Typhoon Warning Center, and international organization that follows tropical systems, has been closely watching the area of tropical disturbance off the west coast of India. However, the area’s potential for development during the next 24 hours remains low. It remains largely disorganized with not well-defined low-level circulation centre. However, vertical wind shear has reduced as the disturbance slowly tracked northward. Maximum winds are between 15 and 20 knots, still below the threshold of a tropical system. Minimum sea level pressure of 1003 mb. In summary, the disturbance remains largely weak. It might improve or dissipate during the next 48 hours.

Original post: 11 AM June 4th, 2011:

A cluster of showers and thunderstorms is located off the west coast of India over the eastern half of the Arabian Sea. This tropical disturbance area is being monitored closely as it “MAY” or “MAY NOT” develop further. A disagreement between various weather models continues with regard to the future of this disturbance. This raises a lot of doubts and please avoid over-believing rumours.

As of now this tropical disturbance lacks a clear well-defined low level circulation centre. It has been facing disruptive vertical wind shear over the last 48 hours as it drifted slowly from southern to central eastern Arabian Sea, where vertical wind shear is less disruptive. Moreover, northwest of the disturbance drier air could be ingested into the system. This disturbance needs to overcome these difficulties. However, optimal sea surface temperatures with warm water as deep as 50-100 meters is a favorable factor for the disturbance along with lower expected shear over central Arabian Sea.

85-91 GHz Brightness Temperatures show deep convection on the western half of the distubance. Image from NRL.