Hottest rain on record? Rain falls at 109°F in Saudi Arabia

By: Dr. Jeff Masters , 11:24 AM GMT on June 07, 2012

Share this Blog
39
+

Pilgrims to the holy city of Mekkah (Mecca), Saudi Arabia must have been astonished on Tuesday afternoon, June 5, when the weather transformed from widespread dust with a temperature of 113°F (45°C) to a thunderstorm with rain. Remarkably, the air temperature during the thunderstorm was a sizzling 109°F (43°C), and the relative humidity a scant 18%. It is exceedingly rare to get rain when the temperature rises above 100°F, since those kind of temperatures usually require a high pressure system with sinking air that discourages rainfall. However, on June 4, a sea breeze formed along the shores of the Red Sea, and pushed inland 45 miles (71 km) to Mekkah by mid-afternoon. Moist air flowing eastwards from the Red Sea hit the boundary of the sea breeze and was forced upwards, creating rain-bearing thunderstorms. According to weather records researcher Maximiliano Herrera, this is the highest known temperature that rain has fallen at, anywhere in the world. He knows of one other case where rain occurred at 109°F (43°C): in Marrakech, Morocco on July 10, 2010. A thunderstorm that began at 5 pm local time brought rain at a remarkably low humidity of 14%, cooling the temperature down to 91°F within an hour.



Figure 1. Thunderstorms at 109°F? This true-color satellite image of Saudi Arabia taken at 2:10 pm local time (11:10 UTC) on June 5, 2012, shows a line of thunderstorms that developed along the edge of the sea breeze from the Red Sea. Three hours after this image was taken, Mekkah (Mecca) recorded a thunderstorm with rain and a temperature of 109°F (43°C.) Image credit: NASA.

More like a hot shower than a cooling rain?
Thunderstorms often produce big drops of cold rain, since these raindrops form several thousand meters high in the atmosphere, where temperatures are much cooler than near the surface. Some drops even get their start as snow or ice particles, which melt on the way to the surface. Additional cooling of the drops occurs due to evaporation on the way down. However, in the case of the June 4, 2012 Mekkah storm, I think the rain was probably more like a hot shower. Large raindrops, like the kind thunderstorms produce, fall at a speed of about 10 meters per second. A balloon sounding of the upper atmosphere taken at 3 pm local time at a nearby station (Al-Midinah) found that the bottom 1000 meters of the atmosphere was 97°F (36°C) or warmer. Thus, the thunderstorms' raindrops would have been subjected to 100 seconds of some very hot air on the way to the surface, likely warming them above 100°F by the time they hit the ground. A classic 1948 study of raindrops found that, in many cases, raindrop temperatures start off cold in the first few minutes of a rain shower, then warm up to within 1°C (1.8°F) of the air temperature within a few minutes. With the air temperature a sizzling 109°F (43°C) at the time of the June 4 thunderstorm in Mekkah, the raindrops could easily have been heated to a temperature of over 105°F (41°C) by the time they reached the surface!

How hot can it be and still rain?
If substantial amounts of liquid water are present on the Earth, the planet will experience rain, as long as some mechanism to lift the warm, moist air and cause condensation can be found. If the climate continues to warm as expected, we should see an increasing number of cases where it rains at temperatures well above 100°F. On Saturday, June 2, the temperature in Mekkah hit 51.4°C (124.5°F), a new record for the city, and just 1.1°F (0.6°C) below the all-time hottest temperature record for Saudi Arabia (125.6°F, or 52°C, recorded at Jeddah on June 22, 2010.) I expect that 20 - 40 years from now, we'll begin seeing occasional cases where rain falls at a temperature above 117°F (47°C) in the desert regions of North Africa and the Middle East.

I'll have a new post by Friday afternoon.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 182 - 132

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15Blog Index



"Dey startin ta pop down hea"
Member Since: June 17, 2011 Posts: 11 Comments: 6439
Quoting CybrTeddy:
The 12z GFS spins up two tropical storms, one in the Caribbean into the Gulf and another that moves out to sea.
That would be awesome if it verifies. we would have Chris and Debby if that happen and my forecast of June will verify of two storms.
Member Since: Posts: Comments:
Quoting weatherh98:


WOW its really coming down north of you
yeah its been north and south of me today, a few showers short lived by my house today
Member Since: Posts: Comments:
Look at the silt accumulation. That is fast:


these are supposedly the same place where the tsunami washed ahore in 1700
Member Since: Posts: Comments:
Quoting DavidHOUTX:


Boo you and all that rain. :( That is exactly what we need.
your time will come,they have been getting alot of rain around Dallas
Member Since: Posts: Comments:
Quoting LargoFl:


Wow, that stuff's just evaporating.

EDIT: I suppose this makes sense, CINH at the 12Z sounding is 129 J/Kg. :(
Member Since: Posts: Comments:
The 12z GFS spins up two tropical storms, one in the Caribbean into the Gulf and another that moves out to sea.
Member Since: Posts: Comments:
Quoting LargoFl:


WOW its really coming down north of you
Member Since: June 17, 2011 Posts: 11 Comments: 6439
Member Since: Posts: Comments:


336 hours out... 1004 mb low off the yucutan

this has prolly been posted but just throwing it out there
Member Since: June 17, 2011 Posts: 11 Comments: 6439
Quoting LargoFl:


Boo you and all that rain. :( That is exactly what we need.
Member Since: August 18, 2011 Posts: 0 Comments: 597
Member Since: Posts: Comments:
Then again it has to be the type of radio or GPS signals along the tracks that are giving off some kind of interference for that to be happening. Might just be worth calling the NWS and see what they have to say. Something is being emitted off those tracks or the Hwy
Member Since: July 14, 2008 Posts: 1 Comments: 9625
Quoting nofailsafe:


Awesome. Here's what we're seeing:




EDIT: Just thought about something: you can clearly see the outline of the coast of Trinity Bay and Galveston Island which makes me wonder if the reason why we're seeing highway 6 is the same reason we're seeing these other two features: temperature change.

IIRC, RF can be refracted by changes in medium density. So what we're seeing is some of the radiation from the transmitter getting refracted by this temperature inversion from warm water to cool land.
Thanks!! i like your observations as well, and the temp explanation seems very plausible.. i am no expert, but i'll run this by the Mrs., who is well on her way :D
Member Since: Posts: Comments:
Member Since: Posts: Comments:
...................surprised there have been no flood warnings so far,hardly any warnings at all today
Member Since: Posts: Comments:
Quoting TomTaylor:
Well we had a 7.2 just two years ago, that's pretty strong already, especially for the type of fault we have.

If you look at past years, earthquake activity was bigger back then.. I seems as if earthquake activity in california is diminishing
Member Since: Posts: Comments:
Member Since: Posts: Comments:
This is my 18th straight summer here in downtown Phoenix, AZ. During July and August, I've observed a similar phenomenon here a few times. One July day about 10 years I observed/measured the late afternoon temperature drop from 113 to 108 with a local passing convective rain shower generating a spattering of hot raindrops. This occurred during the transition from a prolonged period of very hot dry air to a more moist monsoonal flow. During these transitions, the air typically moistens up from top down with high- mid level moisture injected above a very hot dry air mass still anchored in place at lower levels. During the early stage of cloud/storm formation - local cloud buildups occur with rain beginning before a strong cool downdraft from evaporational cooling and outflow gets established - generating hot raindrops from the high base clouds.
Member Since: Posts: Comments:
The sat pics are the 84 hour forecast.
Member Since: September 27, 2007 Posts: 1 Comments: 19537
Quoting Minnemike:
where is this, and can anyone link a radar echo showing it here?
this is piquing my interest, as it may also my PhD seeking wife who specializes in radar and lidar classifications.


Post 117
Member Since: July 14, 2008 Posts: 1 Comments: 9625
Quoting Minnemike:
where is this, and can anyone link a radar echo showing it here?
this is piquing my interest, as it may also my PhD seeking wife who specializes on radar and lidar classifications.


Awesome. Here's what we're seeing:




EDIT: Just thought about something: you can clearly see the outline of the coast of Trinity Bay and Galveston Island which makes me wonder if the reason why we're seeing highway 6 is the same reason we're seeing these other two features: temperature change.

IIRC, RF can be refracted by changes in medium density. So what we're seeing is some of the radiation from the transmitter getting refracted by this temperature inversion from warm water to cool land.
Member Since: Posts: Comments:
Quoting gordydunnot:
Comment for today, area west of Tampa in central gulf is starting to look as good as it gets for this time of year. Old front draped across central Fl.,shear dropping and plenty of moisture. My only caveat is it is this time of year.
yes if this was august i'd be real worried right now
Member Since: Posts: Comments:
Quoting hydrus:
That might be a warning..They are overdue for a strong quake.
Well we had a 7.2 just two years ago, that's pretty strong already, especially for the type of fault we have.
Member Since: Posts: Comments:


here you can see firepits with charcoal that native americans used, in the 2 downward swellings in the black layer, toward the left of the picture.
The layer above that is supposedly "tsunami mud"

The Big One


and from Wiki:

the Cascadia Subduction Zone is a very long sloping fault that stretches from mid-Vancouver Island to Northern California. It separates the Juan de Fuca and North American plates. Because of the very large fault area, the Cascadia Subduction Zone could produce a very large earthquake

The last known great earthquake in the northwest was the 1700 Cascadia earthquake. Geological evidence indicates that great earthquakes may have occurred at least seven times in the last 3,500 years, suggesting a return time of 300 to 600 years. There is also evidence of accompanying tsunamis with every earthquake, and one line of evidence for these earthquakes is tsunami damage, and through Japanese records of tsunamis.[11]

The next rupture of the Cascadia Subduction Zone is anticipated to be capable of causing widespread destruction throughout the Pacific Northwest.[12]

Other similar subduction zones in the world usually have such earthquakes every 100 to 200 years; the longer interval here may indicate unusually large stress buildup and subsequent unusually large earthquake slip.[citation needed]
Member Since: Posts: Comments:
Quoting Articuno:

not to get you freaked out and stuff, but its not good because pressure is building and a big earthquake, maybe above 6.0 could happen.
shes leaving like tomorrow...
Member Since: June 17, 2011 Posts: 11 Comments: 6439
Quoting weatherh98:


Good my mom is in san diego

not to get you freaked out and stuff, but its not good because pressure is building and a big earthquake, maybe above 6.0 could happen.
Member Since: Posts: Comments:
Quoting tampahurricane:
Is Hwy 6 lifted off the ground?


No
Member Since: July 14, 2008 Posts: 1 Comments: 9625
I'm sure that some of this is hype, etc, but it is interesting:
The Giant, Underestimated Earthquake Threat to North America
Member Since: Posts: Comments:
Comment for today, area west of Tampa in central gulf is starting to look as good as it gets for this time of year. Old front draped across central Fl.,shear dropping and plenty of moisture. My only caveat is it is this time of year.
Member Since: Posts: Comments:
Quoting nofailsafe:


You noticed that too?

There's a train track that runs along it on the south side that's raised up a few feet but that should not make a consistent echo like that. And a parked train, while it would have an excellent reflective surface couldn't possibly be that long.

There's also another odd linear anomaly to the north running from US-90 Business east-south-east to the mouth of the Trinity but I don't see any kind of linear features in that area...
where is this, and can anyone link a radar echo showing it here?
this is piquing my interest, as it may also my PhD seeking wife who specializes in radar and lidar classifications.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
The water temperatures have probably risen about 2-3C is the past 3-4 weeks in the Bahamas. It's crazy nice now :) 28+C :)
Member Since: Posts: Comments:
/
Member Since: September 27, 2007 Posts: 1 Comments: 19537
Quoting nofailsafe:


You noticed that too?

There's a train track that runs along it on the south side that's raised up a few feet but that should not make a consistent echo like that. And a parked train, while it would have an excellent reflective surface couldn't possibly be that long.

There's also another odd linear anomaly to the north running from US-90 Business east-south-east to the mouth of the Trinity but I don't see any kind of linear features in that area...
The causeway over lake pontchartrain regularly shows up on radar
Member Since: June 17, 2011 Posts: 11 Comments: 6439
Quoting GeorgiaStormz:
What exactly is this:


It starts as a deepening trough going SE at about 200hrs, dives due south from WA, OR, and ID, through NV, to AR and CA, and then goes back West out to sea before going back north again.
6z and 18z runs out beyond a week tend to do that. Thats a crazy trough for June though
Member Since: Posts: Comments:
Quoting MississippiWx:


I saw that forecast by the climate model, but I'm very skeptical. The -PDO is making it very difficult for warm anomalies to make much headway to the west into the Central Pacific, so I just have a hard time believing the peak of our El Nino will ever be a Modiki one in the Central Pacific.
Honestly when I saw the model run I felt like it developed a modiki el niño because of the persistence of a multidecadal negative pdo. Looking at the run, the equatorial pacific warms at first but then waters on the western side of the tropical pacific begin to cool...which is similar to a negative pdo where we get the waters along the west half of the pacific cooler than normal. End result is the west side cools leaving a pool of warmer water in the central pacific.
Member Since: Posts: Comments:
Quoting GeorgiaStormz:


what happened to the swarm of earthquakes in CA, i cant even find a 4.0 out there right now.



Good my mom is in san diego
Member Since: June 17, 2011 Posts: 11 Comments: 6439
Quoting RitaEvac:
Really don't understand why Hwy 6 shows up on radar, always does this



Railroad runs along it as well

Even high Def radar shows it



You noticed that too?

There's a train track that runs along it on the south side that's raised up a few feet but that should not make a consistent echo like that. And a parked train, while it would have an excellent reflective surface couldn't possibly be that long.

There's also another odd linear anomaly to the north running from US-90 Business east-south-east to the mouth of the Trinity but I don't see any kind of linear features in that area...
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:

Oh yeah, I completely forgot about those. Thanks for the reminder Matt!


Ha! I actually forgot about them myself. :)
Member Since: July 14, 2009 Posts: 51 Comments: 1715
Quoting GeorgiaStormz:


what happened to the swarm of earthquakes in CA, i cant even find a 4.0 out there right now.


It's not a good sign when the pressure is not regularly released....
The plates are still moving along.
Pressures will be building.
Member Since: Posts: Comments:
Quoting GeorgiaStormz:


what happened to the swarm of earthquakes in CA, i cant even find a 4.0 out there right now.

That might be a warning..They are overdue for a strong quake.
Member Since: September 27, 2007 Posts: 1 Comments: 19537
Quoting GTcooliebai:
6.0 in Peru.


what happened to the swarm of earthquakes in CA, i cant even find a 4.0 out there right now.

Member Since: Posts: Comments:
Somewhat interesting..120 hours.500mb vort..gfs..NSSL WRF 4 km grid initialized 00 UTC Jun 07 2012

36 h Total Precipitation (mm)
Member Since: September 27, 2007 Posts: 1 Comments: 19537
Tx 13, the 12z GFS continues with the long range development in Western Caribbean/GOM on the time frame you mentioned earlier of the strong MJO pulse arriving.
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
6.0 in Peru.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Quoting cyclonekid:
Use the ones I gave you a while back.

Oh yeah, I completely forgot about those. Thanks for the reminder Matt!
Member Since: July 6, 2010 Posts: 108 Comments: 30257
Quoting TropicalAnalystwx13:
I'd like to do my own Tropical Weather Outlooks. Too bad they don't make good maps of the Atlantic (mad face).
Use the ones I gave you a while back.
Member Since: July 14, 2009 Posts: 51 Comments: 1715
Quoting FtMyersgal:


Sure hope you are right GT. I have to find a way to get the shields to drop in Lee County. Yesterday all the rain was to my south. Today most of it's north of me. sigh...
I hope I'm right, sometimes these masses of shower and t-storm complex falls apart before they reach on shore. If we can get the front to drop on farther south then the rain chances should increase.
Member Since: Posts: Comments:

Viewing: 182 - 132

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15Blog Index

Top of Page

About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.