Storm Doris - Wednesday PM/Thursday AM

Gaoth Laidir

Nice graph of Doris passing Malin Head.

https://twitter.com/MetEireann/status/834683201364824064

nacho libre

JCX BXC wrote: »

I have a few years experience in these, it's unusual for the TAF to be this far off. To be fair to Met Eireann, it's rare that these storms upgrade so much so close to their occurrence.

surely though
this is where a forecaster experience comes into play given the conditions were ripe for a sting jet, also the fact that it developed quickly and, unusually, tracked over us, rather than 200 miles off the northwest coast, as it usually would.
Anyway i am disappointed to have missed it all. Fair play to the usual heads for all their analysis during the storm.

Gaoth Laidir

nacho libre wrote: »

surely though
this is where a forecaster experience comes into play given the conditions were ripe for a sting jet, also the fact that it developed quickly and, unusually, tracked over us, rather than 200 miles off the northwest coast, as it usually would.
Anyway i am disappointed to have missed it all. Fair play to the usual heads for all their analysis during the storm.

I don't think it was a sting jet. The strongest gusts of the whole system occurred in the west (Galway and Mayo) in the very early stages of occlusion, whereas with a sting jet we'd expect them to occur a bit later on. Also, as a sting jet has dry air descending from above we'd expect to see a lower drop in dewpoints than was observed.

We'd also expect even stronger gusts for a true sting jet event. Even the UK and Netherlands didn't match the gusts at Mace Head and Newport (both stations only 20 metres amsl). Capel Curig (216m) did get 82 knots but that is an exposed site with a valley to its west. The strong winds were just down to a strong gradient on the southwest flank of the low.

nacho libre

Gaoth Laidir wrote: »

I don't think it was a sting jet. The strongest gusts of the whole system occurred in the west (Galway and Mayo) in the very early stages of occlusion, whereas with a sting jet we'd expect them to occur a bit later on. Also, as a sting jet has dry air descending from above we'd expect to see a lower drop in dewpoints than was observed.

We'd also expect even stronger gusts for a true sting jet event. Even the UK and Netherlands didn't match the gusts at Mace Head and Newport (both stations only 20 metres amsl). Capel Curig (216m) did get 82 knots but that is an exposed site with a valley to its west. The strong winds were just down to a strong gradient on the southwest flank of the low.

My apologies. So would it be more accurate to say it was a weather bomb? Also why do you think Met Eireann under estimated it, if mostly amateurs( i understand you are not), and i mean no disrespect by that, can call it accurately, why couldn't they. I understand they are under a greater level of scrutiny, so have to be more cautious, but there intuition should have told them this had potential to be stronger than originally predicted

pad199207

Was the gust of 140KPH at Mace Head official? Gerry didn't mention it on the 6oclock weather last night

MJohnston

nacho libre wrote: »

My apologies. So would it be more accurate to say it was a weather bomb? Also why do you think Met Eireann under estimated it, if mostly amateurs( i understand you are not), and i mean no disrespect by that, can call it accurately, why couldn't they. I understand they are under a greater level of scrutiny, so have to be more cautious, but there intuition should have told them this had potential to be stronger than originally predicted

Genuinely wouldn't be surprised if they're under a little bit of, not pressure exactly but close enough, to keep their TAFs on the conservative side, so as not to provoke unnecessarily early airline cancellations. Presumably if a TAF says that airport ops are very likely to be affected, airlines would cancel flights ahead of time. Whereas they can hedge a bit on the forecast and given Irish weather's propensity to downgrade from forecasts, that might be the safer (financial) bet for the airport/airlines.

Gaoth Laidir

nacho libre wrote: »

My apologies. So would it be more accurate to say it was a weather bomb? Also why do you think Met Eireann under estimated it, if mostly amateurs( i understand you are not), and i mean no disrespect by that, can call it accurately, why couldn't they. I understand they are under a greater level of scrutiny, so have to be more cautious, but there intuition should have told them this had potential to be stronger than originally predicted

By and large they did call it right, stating some damaging gusts to 130 kph. Which exact counties were covered by their warnings I'm not sure but if the public were to read the forecasts then there was no doubt that strong winds would occur in a broad area from the west across to the east, highlighted in their warnings. To hear the comments of some you would think they had missed it completely.

Yes their TAFs were a little on the low side but this is probably down to the meteograms produced by their Harmonie and HIRLAM models, which did show lower potential than the Arpege (which they don't use, I think). Taken over the whole year, however, their performance is above that of "amateurs".

nacho libre

Gaoth Laidir wrote: »

). Taken over the whole year, however, their performance is above that of "amateurs".

Indeed, that is highly likely, but you see perception is key, it's akin to the thankless task intelligence services have;if they get it wrong, no one remembers all the times they got it right; the perception is Met Eireann got it wrong when it really mattered. it's not fair, but that is how it goes

DOCARCH

pad199207 wrote: »

Was the gust of 140KPH at Mace Head official? Gerry didn't mention it on the 6oclock weather last night

According to http://www.met.ie/latest/yesterday.asp

Mace Head had gust of 68kn....126kmh (as did Knock)

Newport had gust of 73kn....135kmh

Oneiric 3

Nobody claimed that 'they missed it completely'.

My question yesterday remains quite valid. Why was the west of the country not included in the severe weather warning on the RTE Weather at 9.30pm on Wed night?



That forecast went on to say that strongest winds would be in the south that night, and in the east in the morning. Again, the region which did actually get the strongest winds was not even mentioned.

Even the ECM 12z run that evening (issued well in advance of the 9.30pm forecast) showed zone of the strongest winds over the west/northwest in the small hours which then transferred to the east by morning.



Something is seriously amiss here. Unless I am missing something?

Gaoth Laidir

nacho libre wrote: »

Indeed, that is highly likely, but you see perception is key, it's akin to the thankless task intelligence services have;if they get it wrong, no one remembers all the times they got it right; the perception is Met Eireann got it wrong when it really mattered. it's not fair, but that is how it goes

Sure I was playing 5-a-side with the lads on Wednesday evening, before Doris arrived the next morning. It was peeing rain alright but almost dead calm. One of the guys said "ah jaysus, storm me arse". If people can't read/listen to a forecast that has a storm for the following morning then what hope do ME have?

Oneiric 3

nacho libre wrote: »

Indeed, that is highly likely, but you see perception is key, it's akin to the thankless task intelligence services have;if they get it wrong, no one remembers all the times they got it right; the perception is Met Eireann got it wrong when it really mattered. it's not fair, but that is how it goes

Of course, Met Éireann usually spot on, no one is saying any different. However, we were dealing with a fairly serious weather situation here, and despite the models issued that evening showing severe winds over the west/northwest, focus remained on the east. This is more than just 'perception' Nacho, this is reality.

Gaoth Laidir

Oneiric 3 wrote: »

Nobody claimed that 'they missed it completely'.

My question yesterday remains quite valid. Why was the west of the country not included in the severe weather warning on the RTE Weather at 9.30pm on Wed night?



That forecast went on to say that strongest winds would be in the south that night, and in the east in the morning. Again, the region which did actually get the strongest winds was not even mentioned.

Even the ECM 12z run that evening (issued well in advance of the 9.30pm forecast) showed zone of the strongest winds over the west/northwest in the small hours which then transferred to the east by morning.



Something is seriously amiss here. Unless I am missing something?

I think it was because it had looked all along that the storm would be deepening as it crossed the country and therefore the strongest winds would be felt in the east.

Oneiric 3

Gaoth Laidir wrote: »

I think it was because it had looked all along that the storm would be deepening as it crossed the country and therefore the strongest winds would be felt in the east.

Not really:


West/NW winds are nearly always going to have an huge impact on the west coast even if a low is explosively deepening as it crosses the country.

Gaoth Laidir

Oneiric 3 wrote: »

Something is seriously amiss here. Unless I am missing something?

What do you think is amiss?

nacho libre

Oneiric 3 wrote: »

Of course, Met Éireann usually spot on, no one is saying any different. However, we were dealing with a fairly serious weather situation here, and despite the models issued that evening showing severe winds over the west/northwest, focus remained on the east. This is more than just 'perception' Nacho, this is reality.

I was not clear. I think there is the perception in the minds of the general public that they get it wrong quite often, when the reality is quite the opposite, however that said they did get this forecast slightly wrong.
Perhaps the reason they got this slightly wrong is due to not using Aperge.

Gaoth Laidir

Oneiric 3 wrote: »

Not really:

West/NW winds are nearly always going to have an huge impact on the west coast even if a low is explosively deepening as it crosses the country.

These are two 12Z 925 hPa charts for midnight and 6 am of Doris. These were the latest available at the time of the broadcast. They show a distinct strengthening in the east (06 am).

Cloudio9

nacho libre wrote: »

I was not clear. I think there is the perception in the minds of the general public that they get it wrong quite often, when the reality is quite the opposite, however that said they did get this forecast slightly wrong.
Perhaps the reason they got this slightly wrong is due to not using Aperge.

mmmm in the eyes of the public they got it right. They said it'll be windy, it was windy. Most people don't pay any attention to yellow vs orange warnings.


The general public get annoyed when they plan a Saturday BBQ in July based on a forecast and it ends up being a washout.

Oneiric 3

nacho libre wrote: »

I was not clear. I think there is the perception in the minds of the general public that they get it wrong quite often.

Is there though? I think the vast majority of people don't really care as much on the pedantic details of weather forecasts as we enthusiasts do; they just want to know if it will rain or not or if there is some nice weather on the way. I doubt they ponder on the substance of a forecast once they have viewed it.

I recall a few years back when Evelyn C apologised live on air to the people of Dublin for getting a bit more rain that was forecast, which really wasn't much in the end. Yet we got a gale in many parts of Connacht, an area not included in the 'Orange Zone' or the actual forecast I seen, which felled trees and no doubt resulted in minor structural damage in the worst hit areas and this is put down as forecast that was 'slightly wrong'? despite the ECM basically nailing this on in advance?

I more than ever stand firm on what I have said.

@G.L. I think I have more than explained my position on this already.

Oneiric 3

Gaoth Laidir wrote: »

These are two 12Z 925 hPa charts for midnight and 6 am of Doris. These were the latest available at the time of the broadcast. They show a distinct strengthening in the east (06 am).

You miss my point.
ECM showed equally strong winds in the W/NW at 100m as it did in the east. Also, as I have said, Exposed W/NW coasts are still prone to strong westerly/NW winds even if the isobaric gradient is slightly less tight that overland in the east.

As per the ECM12z forecast on the day in question: (3 hour increments)

nacho libre

Oneiric 3 wrote: »

Is there though? I think the vast majority of people don't really care as much on the pedantic details of weather forecasts as we enthusiasts do; they just want to know if it will rain or not or if there is some nice weather on the way. I doubt they ponder on the substance of a forecast once they have viewed it.



/QUOTE]

Precisely because they are not into the detail or how complex the weather is,you will often hear the general public say Met Eireann haven't a clue/ what are they paid for/or you can't trust them. The July washout that caught them out is what is remembered or the non snow event in Donegal , not the vast majority of times they get the forecast right. Maybe this is just human nature, we remember the mistakes more readily- of course in some cases, depending on the gravity of the mistake, that is understandable.

Doctor Shivering

The public forecast focused on an area where up to one million people were heading to work
I'm in the east and often been under a heavy rain shower whilst the tv forecaster casually waves an arm saying mostly dry on the map ignoring my plight and that of 20,000 other people in the area..
The UK are big enough for regional tv with regional forecast bulletins seen only in local areas that can hone in on parts of counties even
We are not

Oneiric 3

"Precisely because they are not into the detail or how complex the weather is,you will often hear the general public say Met Eireann haven't a clue/ what are they paid for/or you can't trust them. The July washout that caught them out is what is remembered or the non snow event in Donegal , not the vast majority of times they get the forecast right. Maybe this is just human nature, we remember the mistakes more readily- of course in some cases, depending on the gravity of the mistake, that is understandable"

I'll take your points Nacho and of course, we'll always remember the wrong forecasts.

However, that the west was not included, or even mentioned, in the warnings about this relatively severe event on the 9.30pm forecast, which is probably one of the most watched forecasts either on TV or the web in this country, confirms to me where the priorities of our 'national' institutions really lie.

Oneiric 3

Doctor Shivering wrote: »

The public forecast focused on an area where up to one million people were heading to work
I'm in the east and often been under a heavy rain shower whilst the tv forecaster casually waves an arm saying mostly dry on the map ignoring my plight and that of 20,000 other people in the area..
The UK are big enough for regional tv with regional forecast bulletins seen only in local areas that can hone in on parts of counties even
We are not

And your point?

Gaoth Laidir

Oneiric 3 wrote: »

You miss my point.
ECM showed equally strong winds in the W/NW at 100m as it did in the east. Also, as I have said, Exposed W/NW coasts are still prone to strong westerly/NW winds even if the isobaric gradient is slightly less tight that overland in the east.

As per the ECM12z forecast on the day in question: (3 hour increments)

Pound for pound such winds in the west would be a lot more "normal" than in the east and as such the impact on the public would be less notable. However the ECM 925 hPa charts did show the potential for higher gusts in the east, and it is the gusts that were the main feature of their forecasts.

Oneiric 3

Gaoth Laidir wrote: »

Pound for pound such winds in the west would be a lot more "normal" than in the east and as such the impact on the public would be less notable. However the ECM 925 hPa charts did show the potential for higher gusts in the east, and it is the gusts that were the main feature of their forecasts.

Considering that Casement & Dublin Apt have higher mean wind speeds on a monthly and yearly basis than all inland western stations (except for Shannon Apt), I would disagree that we are more 'used' to these winds than the east. The west coast itself, sure, but there is more to the west than just exposed coasts.

Notwithstanding, even if it was the case that such winds are more 'normal' on this side of the island, I'm not sure this is any excuse to exclude western regions from warnings of strong winds on a national media outlet? All mean wind speeds are comprised of gusts and the lulls: no less at ground level, 100 m or at the 925hPa level. Also, your chart shows a snapshot of 925 winds at both midnight and 6 am. The peak of the winds in here in the west was between both these times.

Gaoth Laidir

Oneiric 3 wrote: »

Considering that Casement & Dublin Apt have higher mean wind speeds on a monthly and yearly basis than all inland western stations (except for Shannon Apt), I would disagree that we are more 'used' to these winds than the east. The west coast itself, sure, but there is more to the west than just exposed coasts.

Notwithstanding, even if it was the case that such winds are more 'normal' on this side of the island, I'm not sure this is any excuse to exclude western regions from warnings of strong winds on a national media outlet? All mean wind speeds are comprised of gusts and the lulls: no less at ground level, 100 m or at the 925hPa level. Also, your chart shows a snapshot of 925 winds at both midnight and 6 am. The peak of the winds in here in the west was between both these times.

When it comes to stats, you're one guy I ain't gonna argue with! However, Met Éireann's charts do show much of the west to be the same or slightly higher on mean speeds, and substiantially higher on gusts, than the east.



But anyway, onwards and upwards to Ewan.

Doctor Shivering

Oneiric 3 wrote: »

And your point?

Northern Ireland is 6 counties in Ulster
If we were part of the UK,there'd probably be a BBC IRL EAST ,BBC IRL West and a BBC IRL Munster with detailed forecasts after the regional news bulletin's specific to areas not covered in the national forecast
Those would be the forecasts people pay most attention to in that case

National forecasts especially our one with limited resources with extreme weather can only be reasonably expected to dwell on where the biggest audience's impacted are and in this case ,the extra consideration of where the storm was going to be when millions were commuting as opposed to sleeping

Gaoth Laidir

Graphs from Doris...

Mace Head


Knock Airport


Belmullet


Claremorris


Dublin Airport


Casement

Gaoth Laidir

Max gusts