Sunny spells, but unsettled weather continues

Even though here in Valle Gran Rey there was no more rain since the downpour on Friday and no significant precipitation elsewhere in the Canary Islands, the weather warnings remain.
There is calm with only a thin layer of broken cloud and the sun coming through at the moment, but the weather situation is dominated by warm and unstable masses of air originating from an area of inter-tropical convergence while the low pressure system in the west is slowly filling and moving very gradually closer to the Canary Islands. It should dissipate within the next three days, and a very large high becomes established over the central north Atlantic which should end the present unsettled spell.
The forecast for today until Tuesday, however is for more unsettled weather with scattered, sometimes heavy showers,  occasionally strong and gusty winds (more on high ground) and a few sunny spells.
Warnings are in effect for the western islands of El Hierro, La Gomera and Tenerife, with La Palma at the highest risk.

This morning's analysis with satellite overlay (OPC/NOAA)

Warnings extended in Canary Islands (contd.)

As this is an ongoing, developing story and an interwoven chain of events, today's updates will be added to yesterday's post see below or click: Warnings extended in Canary Islands

Warnings extended in Canary Islands

After a relatively calm night with a much clearer sky, another band of showers is moving in from southwest. Weather warnings have been extended until this afternoon:

Showers (some heavy), isolated thunderstorms and strong and gusty winds on high ground are all imminent !

It is beginning to rain as I write in Valle Gran Rey, La Gomera.

Satellite picture :

For history, details and development of this weather situation go to my previous post : Hurricane Sandy indirectly affecting Canary Islands

Updates:

#1  ( 5 pm):

The Spanish met. office (AEMET) has cancelled nearly all warnings in the Canaries (except for the island of La Palma and the mountain regions of Tenerife) up to and including Saturday.

The Canarian Society for Metereology (ACM), however has released a red alert warning of isolated thunderstorms, heavy showers, and strong and gusty winds in and near the mountains - with the western Canaries most at risk.I would take their advice and remain cautious.

The low to the west of the Canary Islands is still in place and slowly approaching, but It will eventually begin to gradually fill and weaken during its approach. It will still affect our weather negatively until Sunday at least, however.

The weather here on La Gomera today has been a mix of scattered moderate showers, moderate winds (stronger in the mountains) and some sunny spells. The temperature remains fairly high for this type of weather at around 25ºC.

There are no reports of any significant incidents, but roads and paths remain dangerous with lots of debris being reported. Lots of crews are out on this public holiday clearing roads and blocked drains.

Enhanced Satellite image of late this afternoon. (NOAA)

#2   ( 8 pm):

It has been raining moderately for the past 45 minutes and 

as you can see on the rainfall radar, the band of showers

has reached the Canary Islands and La Gomera cannot be

seen under the rain reflection on the screen, As I write the rain is increasing ...
...and 10 minutes later decreases to light...

#3   ( 10:15 pm):

Heavy rain has been falling in Valle Gran Rey

for the past 30 minutes and visibility is 

greatly reduced. 

All observations show that cells of heavy precipitacion 

have developed very rapidly to the SW and have reached 

the SW of the Canary Islands.

#4    ( 01/11/12 - 11:45 pm ):

There's no let-up ! Still raining quite strongly, and the

barranco (a normally dry riverbed on the floor of the

 valley) is like a river in spate now.

The heavy rain has reached many parts of Tenerife now, not to mention the island of El Hierro.
... ah yes, the spanish official weather service under the Madrid ministry for the environment (etc.) has woken up to the facts on this holiday and has issued a rain warning again.




#5   (02/11/12 - 1:30 am)

It is still raining in Valle Gran 
Rey and many parts of the western Canaries. 
In Valle Gran Rey we're possibly
a bit more worried because 71 years ago on Halloween 1941 there was an event locally referred to as 'the great flood',when torrential rain did a lot of damage here and in other parts of the island. Lives and livestock were lost and to this day the event is regularly remembered and discussed.

During yesterday some places in the western islands registered between 50 and 100 litres/m2 of rain already.

On the right the 'rainbow' satellite picture taken at midnight (Meteosat/NOAA)


#6  (02/11/12 - 3:30 am):

Still raining and now there's a thunderstorm not too far 
away in the southwest with a very low rumbling thunder.

This radar screenshot on the right shows the accumulated precipitation for the past six hours. El Hierro as well as parts of Tenerife got most of it, with La Gomera showing the highest amount.



#7...at 7 am  (02/11/12)

...still raining, but there was very little wind all night where I live. There were a good few rockfalls during the past few hours and the thunderstorm lasted for more than an hour, but discharged mostly over the sea. The rain was mainly moderate, but quite heavy at times.


A big bulldozer went up the mountain on themain road in the dead of night - probably to clear the road of rocks and debris.                                                                        

The three images are basically the same satellite picture

taken at 6 am from Eumetsat but have undergone different
enhancements by NOAA to allow a more precise interpretation.
On the top right is 'infrared 2', below that is 'avn' (used for aviation), and at the bottom right water vapour is shown more clearly.
Anyway all three testify that there is still plenty of development taking place when compared with previous images.





All images can be clicked to enlarge 





 

The rain just now has become very

light, and later today the weather should

improve considerably - but CAUTION: there remains a risk of sudden changes. 

#8  at 8:30 am  (02/11/12):

...you might have guessed it: Rain is lashing down again after a brief respite and another thunderstorm can be heard approaching from SW.

The 'barranco' during the pause in the rain early this morning

More bands of precipitation moving in from SW  (8:20 am)

#9  at  10:30 am  (02/11/12):

The rain has stopped for the time being here in Valle Gran Rey on La Gomera and the sky is still overcast but much brighter.
Rain is however being reported from other areas in the Canaries and more rain in the form of showers is forecast for the next couple of days, but more breaks are likely. With the almost tropical air coming up from the SW the temperature should remain pleasantly high. ACM have just lowered their alert level from red to orange, while AEMET have issued yellow warnings for wind and rain from today and until Sunday.

Ports and airports are operating normally and no significant incidents were reported.
Locals are welcoming the rain like an early Christmas present !

The type of weather (warm + humid) we're having should help the fungi and mushrooms in the forest of the national park to grow again, like this one spotted a couple of days ago growing on the trunk of a tree ^ - with a worm (on the top left) having a feast.



#10  at  1:25 pm (02/11/12):

It is starting again - a thunderstorm is fairly close to La Gomera,getting closer every minute, and rain of large drops is falling. 

Radar image taken at 1:10 pm

#11  at 5:45 pm  (02/11/12):

Well, well, well - since the last update I was 'out and about' a lot and had to witness a 
cloudburst, of such intensity and duration - so locals tell me - that hasn't happened since 1975. 
I'm soaked to the bone, just arrived home tired, hungry and wet, with gigabytes of poor quality visual footage to sort out, information from the 'elders' to mull over, after discussing historical weather events with local farmers and fishermen while humouring disgruntled and stuck tourists. In short: I could write an illustrated book about the past few hours...
So please bear with me and maybe you won't be disappointed. It just might take some (?) more time, if I don't just collapse with fatigue.
Hope to see you later...
Go to homepage or click: Weather warnings still in effect in Canary Islands

Weather Warnings for Canary Islands (contd.)

Today's Updates will be added at the bottom of yesterday's post.

See below or click:Hurricane Sandy indirectly affecting Canary Islands

Hurricane Sandy indirectly affecting Canary Islands

WEATHER WARNINGS for CANARY ISLANDS

There are warnings of strong winds, scattered thunderstorms and moderate to heavy rainfall for La Gomera and all the western Canaries, later extending east. It will remain fairly warm however with around 25ºC. (See bottom of post for 9 # updates)

A very complex weather situation has produced a large area of low pressure far west of us. This low is slowly approaching and will be followed by another, while a further two low pressure systems are in the north preventing the usually rapid passage of the western lows. This could cause the precipitation associated with the western low to become almost stationary over the Canaries and bring some more prolonged spells of rain. 

To add to this potential, the large low relatively far west of us is bringing in extra tropical energy from the outer southern flanks of the headline-making storm Sandy which is affecting the east coast of the US. The large low in turn may be partially to blame for storm Sandy to have hit the eastern United States. Shot-lived tropical storm Tony formed subsequently to the formation of Sandy, didn't come to much but absorbed huge amounts of warm moisture which then spawned the almost stationary low affecting these islands for the next few days...

Well, there's more to it - but I won't bore you further.

What does it mean for the Canary Islands ?

1) From  today until Thursday morning strong to gale force gusty winds (prevailing 
    southwesterly) can be expected  - especially on higher ground.

2) For the same period of time thunderstorms and showers, some heavy, are forecast.

    The showers may merge into longer spells of rain. Some localised flooding
    may occur.

3) After the prolonged drought this year, the above conditions may lead to landslides and

   rockfalls in mountainous terrain - so hiking tours should not be undertaken.      

4) If you need to drive, take extra care.

5) Higher waves could make swimming very dangerous at exposed beaches.

 Chart for tonight/Wednesday morning. Oct. 30th/31st (Source OPC/NOAA)

               

UPDATE #1 (3pm):

The governments of the islands of La Gomera, El Hierro, La Palma and Tenerife have activated their emergency plans as a precautionary measure.

The situation at midday

Blue and red areas are heavy
rain approaching from the SW
(Source: NOAA)

UPDATE #2 (6pm):

The wind is rising and the sea is churned-up. The sky is like lead, covered with low cloud. Rain has been very light so far in Valle gran Rey, but some other places in the Canaries have had substantial amounts of rain already, and wind gusts of between 100km/h and 150 km/h have been reported. 

The 'low in the west' now is a proper storm system with a central minimum pressure of

about 990 mb.

The rain warning for Valle Gran Rey comes into effect from 9pm tonight.

This photo of a cloud formation was taken late this afternoon in the south of Tenerife with a mobile phone.
The photo is real and not edited ! It was named 'nubepelicula' (movie cloud) and appeared in 'foro acanmet'
(c) Rigoberto Rodríguez

UPDATE #3 (10:55 pm):

The situation at the moment appears to have calmed, but forecasters are warning that the danger hasn't passed yet. There is a very charged atmosphere in the air with an unusually high temperature in some places.

Today saw lots of relatively minor incidents, such as cars damaged by fallen branches, some walls, fences, signs and lamp posts blown down. The worst affected areas were parts of the island of La Palma and the north of Tenerife. Flooding was minimal.

...and just when everyone started to expect more substantial rain, the unexpected happened: 

A forest fire broke out in several places a couple of hours ago close to the town of Los Realejos on Tenerife.

The fire is in a pine forest close to a densely populated area and was caused by strong

winds blowing down a high-tension power line which supplies a large area. Now the power had to be switched off to allow fire brigades tackle the fire.

Rain would be welcome there now...

30-10-12  UPDATE #4 (11:55 pm):

Rain Radar 23:40 UTC

A light rain is beginning to fall, but the rain radar is showing

ominous reflections moving in from the southwest...

The fire brigades are hoping to bring the fire in Los Realejos

under control within the next few hours

31-10-12  UPDATE #5  (1am):

Echotop Rain Radar 00:40 UTC

The light rain has stopped again, but as of midnight tonight

there is an orange alert in effect for  30mm of rain in one 

hour and up to 100mm in 12 hours. 

As you can see on the latest radar screenshot the situation

is still developing...

31-10-12  UPDATE #6  ( 7am):

Echotop Rain Radar 06:40 UTC

Persistent moderate rain has been falling for more than an hour now, especially on La Gomera and Tenerife. The rain appears to be intensifying. A short while ago I heard rocks falling in an uninhabited part of Valle Gran Rey.
Warnings are in effect until Thursday morning.

31-10-12   UPDATE #7  (8:20am)

The rain has intensified and a thunderstorm is almost over Valle Gran Rey. The 'barranco' (a normally dry riverbed) is running with lots of water and debris.
People in the western Canary Islands have been asked not to travel unless necessary and to be very cautious if doing so.
The fire in Los Realejos, Tenerife has been brought under control with the help of the rain.

31-10-12  UPDATE #8 (12 noon):

It has been raining continuously since early

this morning, but thankfully the rain was only moderate. A second thunderstorm over Valle Gran Rey about an hour ago passed without incident.

On La Gomera and on the other Canary islands only minor incidents and some traffic disruptions were reported up to now.

The satellite picture on the left shows the train of showers crossing the Canaries from

the southwest.

Roads are treacherous with flooding and debris: CAUTION !

31-10-12  UPDATE #9 ( 7pm) :

The continuous rain, which lasted for more than 8 hours stopped about half an hour after

my last post here, and we've only had a couple of light showers since then. The sun even came out for brief periods ! All in all a lot of rain came down, but thankfully no major incidents were reported in the Canary Islands. All preventive measures were applied and most people took precautions, thanks to the warnings and the preparedness of the authorities in the face of a potentially very dangerous situation.

The level of warnings has been lowered now to yellow  and is in effect until tomorrow morning 9 am. The possibility of isolated heavy showers still exists on all of the Canary Islands, and strong wind gusts may still occur.

However, the worst is over for now.

Here's a photo I took at about sunset tonight, which shows a clearing sky in the west (on the right):

+ NEW POST NOV. 1st : Warnings extended in Canary Islands