Emirates Meteorology Blog » Climatology

Looking back at Arabian Sea Cyclones

Ahmed — Tue, 25 May 2010 10:21:09 +0000

The Arabian Sea usually produces a few tropical storms or even cyclones (mainly in May/June/Oct/Nov). The image below shows tropical storms tracks from 1891 to 2007 produced by the Indian Meteorological Dept (IMD).

North Indian Ocean Cyclones Tracks

It is very clear that among the Gulf countries, Oman and Yemen are at higher risk of getting hit by tropical storms or cyclones every year. While the Arabian Sea produces storms annually, Oman and Yemen are not affected every year. Even when they are affected, usually the storms are not severe (tropical storms or depression with winds below 119 Km/hr) and don’t reach cyclone status (winds above 119 Km/hr). However, the amount of rain that falls can be fatal by itself. Moreover, there are exceptions such as Cyclone Gonu which entered Gulf of Oman as a category 1 cyclone, but not before reaching a category 5 status while moving over the Arabian Sea before reaching Oman.

And after Cyclone Gonu shattered records by being the strongest storm in the Arabian Sea and by taking an unusual track into the Gulf of Oman, we need to keep an eye on the Arabian Sea for future storms development. During the next 45 days, chances are that another tropical storm or cyclone could form over the Arabian Sea. Although most of them hit India, we need to remeber the potential of those storms to move to the west or northwest approaching Oman or Yemen.

2009 – 2010 Winter So Far in the UAE and the Gulf

Ahmed — Fri, 08 Jan 2010 06:54:51 +0000

Since we have gone through around 40% of this winter which started in December 2009 and lasts till the end of February 2010 (meteorological winter). I have a few points to highlight:

Surface Chart. High Pressure dominates the region

Precipitation: Late November and December were wetter than normal across many parts of the Arabian Peninsula, the Arabian Gulf, and the Gulf of Oman. All gulf countries experienced rain this Decemebr including Saudi Arabia, Kuwait, Bahrain, Qatar, Oman, and the UAE. Two areas of exceptional rainfall: 1) Western Saudi Arabia along the Red Sea, especially Jeddah and its surrounding, where floods have wrecked havoc on Jeddah late November with probably more than 100m in less than 24 hours if not less than 12 hours. 2) The UAE between Dec 11 and 13 experienced heavy rain and thunderstorms with more than 100mm of rain accumulation in central UAE, mainly between Abu Dhabi and eastern mountain of the UAE near Al Ain and Oman borders. Around150mm were recorded in Al Foah in the UAE in just 48 hours. Another good thing about December is how frequent those troughs and low pressures were, with weekly rain events in the region, and an absence of high pressure systems that usually bring cold air.

Temperature: This winter is exceptionally warmer than normal, especially in northern Arabian Peninsula. If you look at Kuwait for example, the normal average high temperature in Dec is 19c, but actual high temperature in Dec 2009 is 21c with 17 days of highs of 22 or higher. The first week of January also recorded average high of 21c even though normal high is 18c, and it looks that the next 2 weeks are going to be even warmer with average highs of 22c, reaching 26 by mid January. There might be times where eastern gulf countries like the UAE, Oman, and Qatar will experience cooler days! This warmer weather is not confined to Kuwait. In fact, the whole region is warmer, but it is more visible in northern Arabian Peninsula which is accustomed to cold winter and not a mild one. In the UAE winter has also been warmer than average, but I guess it is slightly above normal. And those frequent rain waves made things feel like winter.

What is Next? Things have calmed down big time after Jan 1st, 2010 which brought heavy thunderstorms and hail to the UAE. A high pressure has taken control of the regional gulf weather. But cold weather has not yet made its way to the region as typical with every January and December. It seems Mr. Cold Air has decided to spend his winter vacation in Europe! And the outlook for the next 10 days is more calm mild sunny weather for the whole region with a bit of a warming trend sometimes. But, the UAE and northern Oman could experience a few isolated thundershowers between Sunday and Monday (very low chance) as an upper low dives in from NE Iran. Otherwise, things seem to be pretty calm.

Isn’t it Time to Ride this Roller Coaster?

Ahmed — Wed, 04 Nov 2009 19:18:42 +0000

Isn’t time to ride this? I don’t think we will have to wait that long here in the UAE and the Arabian Peninsula.

A message to Mr. Winter and Miss Jet Stream: Please start doing your magic.

October Long Time Ago in Arabia and the UAE

Ahmed — Fri, 16 Oct 2009 05:21:18 +0000

Almost certainly, October is generally a calm and dry month, marking the transition between summer and winter with almost no rainfall in the UAE. During a normal October, cold fronts are still far away (somewhere in the Middeteranian), the Indian Monsoon is retreating, and tropical lows in the Arabian Sea could be forming (sometimes). So, the UAE and the Arabian Gulf countries become largely islolated from any notable weather forces. But there have been a few of extreme October months in Arabia long time ago. In fact, October proved to be a month where winter and tropical rain are both possible in the UAE even if our average rainfall is zero. Of course, our average is not based on long-term data.

October 1997:

During exceptionally wet winters, October cold fronts are possible but extremely rare. The last time UAE had an October cold front with measurable rainfall was in 1997, which could be our only measurable winter rainfall in October for the last 20-30 years (with only a trace recorded in 1995 and 2000). And I’m not talking about mountainous afternoon thunderstorms that form regulary during the warm months in the UAE.

October 1997 rainfall

October 1948:

This was a strange October. Apparently a tropical storm (cyclone?) hit southeast Oman, and then the tropical (storm/low/depression?) moved northward to the UAE and Oman. The storm dumped a lot of rainfall to SE Oman (100-300mm estimated) before bringing heavy rain to the UAE (around 50mm). While I didn’t find other sources online that talk about this storm in details, the below rainfall map tell part of the story.

October 1948 rainfall

October 1925:

There are talks of severe thunderstorms hitting the Arabian Gulf countries during the early days of October 1925. That should have been a very rare and early october cold front I guess. There are talks of how bad it was since many fishermen died and some say there were tornadoes as well. While I can’t prove so many things about it, the rainfall map shows winter rainfall over a large part of Arabia in October 1925. I guess it is too old to have some accurate details about it.

October 1925 rainfall

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Coming back to October 2009, it seems everything (so far) is behaving normally. No early cold fronts nor intrusive tropical lows.
But I’m keeping an eye on late October.

Introducing Meteo Wall for Weather Forecasts

Ahmed — Thu, 08 Oct 2009 03:51:26 +0000

In an attempt to make this blog more exciting, I have introduced my own forecasts page. It is named Meteo Wall. You will find the link below the header bar. It will be updated and improved over time.

Click here to access Meteo Wall

Screenshot of Meteo Wall

Fall and Winter Seasonal forecast for Arabia

Ahmed — Thu, 03 Sep 2009 18:34:25 +0000

First of all, meteorological Autumn has begun on Sep 1st. Temperatures should start declining, but very slowly. And since humidity picks up in the UAE during September, a change in real feel temperature is not likely.

Anyway, looking ahead for the months of November to February during which westerlies start affecting Arabia, I will show below the corresponding seasonal forecast. With El Nino picking up, we might experience a different winter. Although not statistically proven, El Nino (particularly strong El Nino) years corresponds to wetter winters across Arabia. A great example is 1982 and 1995/1996 winters.

The US NWS/NCEP seasonal forecast predicts a wetter winter across most of Arabia and SW Asia with at least 50% above normal precipitation with the months of Jan-Mar being potentially 65-75% above normal in the UAE. Moreover the European ECMWF seasonal forecast also predicts a similar scenario with around 50-60% above normal precipitation across the Arabian Gulf countries, with the months of Nov-Feb being 60-70% above normal in the UAE. One more organization that issues seasonal forecasts is the IRI institute. Their forecasts predicts a drier winter, but I have seen them predicting such forecasts even for wet winters in the past few years. Maybe I like to believe what I want to believe. Temperature-wise, all seasonal forecasts predict warmer than normal weather (blame global warming).

What do I think? I expect a wetter winter and probably an early arrival of the westerlies and the arrival of jet stream.

UAE Weather for Dummies!

Ahmed — Sat, 27 Jun 2009 17:15:12 +0000

In case you are wondering how the climate is in the UAE, this post will give you more than that. Along the way, I will be answering the following interesting questions as well:

1- Did it ever snow in the UAE?
2- Did a tornado ever affect the UAE?
3- What about cyclones?
4- Does the temperature reach the freezing point in the UAE?
5- Does it rain in the UAE during the summer?

First the UAE is situated on 24N 54E. Below is a map of the UAE. Click here for google map.

Hajar mountains cover NE UAE

The UAE has a very dry climate. Summers are extremely hot and humid with high temperatures in the 40s. However, winters bring pleasant temperatures with coastal highs in mid 20s and lows in teens. Winter precipitation is highly irregular, meaning that a certain winter can bring either no/ little rainfall or much rainfall compared to average.

So let’s answer the weird questions mentioned above:

1- Did it ever snow in the UAE?
Yes it did. But it happened on UAE’s highest mountain (Jees mountain, around 1700m above sea level). Temperature there often drops to or near freezing level during winter. With the passage of cold front, snow can fall there witht the right conditions. There are 2 snow events that are well-documented (in Jan 2009 & Dec 2004). And there are probably other non-documented cases. Click here for more.

Snow covers Jees mountain Jan 2009 (Gulfnews)

2- Did a tornado/waterspout ever affect the UAE?
Yes. Severe thunderstorms can develop tornadoes. On Jan 1st, 2003, a waterspout formed near the shores of Sharjah and Ajman. But it dissipated before causing any damage. Click here for a video of a tornado on Dec 29 2006 near Ras Al Khaymah.

Jan2003 waterspout

Summer twin tornadoes Oct 25th 2007 in Madam area, UAE

3- What about cyclones?
While Arabian Sea cyclones mainly affect India, Pakistan, and Oman, Cyclone Gonu almost managed to hit the UAE in 2007. But it did send tons of waves to UAE East coast. Read more here.

Cyclone Gonu effect on UAE East

Cyclone Gonu in Gulf of Oman (Jun 2007)

4- Does the temperature reach the freezing point in the UAE?
UAE Jees Mountain can get as cold as -5c during winter. Elsewhere, the open desert of the UAE can get close to the freezing level especially if you are away from the sea during cold, calm wintry nights and after the passage of cold fronts.

5- Does it rain in the UAE during the summer?
The UAE Hajar mountains help produce local thunderstorms in the afternoon during summer and early autumn even though other parts of the country swelter under high temperatures and humidity levels.

: Jun 8, 2006 NE UAE mountains

Now I’m thinking of UAE Weather for Dummies Part 2

Summer Solstice; the longest day in 2009

Ahmed — Thu, 25 Jun 2009 12:38:41 +0000

The sun shines directly on the Tropic of Cancer during Summer Solstice (Image source: Wikimedia)

Well, June 21st was the longest day in the northern hemisphere in 2009. This is known as summer solstice during which our sun directly shines on the Tropic of Cancer. And we all know that the UAE is positioned very close to the Tropics of Cancer. The length of the day in Dubai was 13 hours and 42 minutes on June 21st, 2009.

Although the next days will be slightly shorter, the hottest days won’t arrive until July and early August as the northern hemisphere hasn’t yet reached its maximum seasonal heat (seasonal lag).

It is interesting that in the southern hemisphere, it is the complete opposite with Winter solstice and the shortest day in 2009 being the main discussion.