Heatwave for end of July?

Gonzo

the RTE forcast earlier had the weather settling down but temps around the 16-18C mark for next week

pauldry

Yes i reckon the warmest of the temperatures are gone for another year though at least things will be drier than last year.

Early 20s still possible but I am not seeing the high twenties that some others are seeing:(

lucy2010

I can see how the high temps may be reached.. we it 24.4 in dense low cloud & a sea breeze. Imagine if the sun had of come out earlier !!!!

Gonzo

next week's 'heatwave' has constantly being downgraded and now next week is looking very dissapointing even unsettled with plenty of showers and quite cool temperatures from Tuesday, Temps will struggle to hit 18C in places

lucy2010

http://www.wetterzentrale.de/pics/avnpanel1.html Charts are still looking pretty red & nice .

Its a wait & see gameme thinks. But ..... no rain since Friday whooooooooo

mike65

The farming forecast was a damp squib. No stable high pressure this week. The south/east will get the best of what meagre rations are on offer.

Trogdor

Apologies, I haven't been able to view the forums as much as i'd like lately..this thread probably should have been closed a good while back but seeing as clamness seems to have returned and it's got back on track i'm going to leave it open:) Any more bickering and it will be locked though.

up for anything

trogdor wrote: »

Apologies, I haven't been able to view the forums as much as i'd like lately..this thread probably should have been closed a good while back but seeing as clamness seems to have returned and it's got back on track i'm going to leave it open:) Any more bickering and it will be locked though.

Is that clamminess due to the high humidity do you think?

M.T. Cranium

I think he means some people clammed up. I tried to clam up but found myself with sore mussels.

Domscard

Maybe he meant claims - there were quite a few outrageous claims doing the rounds for a while

Su Campu

Yesterday's 12Z Valentia sounding showed a freezing level around 4.1km (~13,500ft), very high for this part of the world. Corresponding 500-1000 thickness 565dm and tropopause height around 13kms (~42,500ft) and -65°C.

M.T. Cranium

Good morning, the very warm wedge is approaching ... and I continue to think it has been underpredicted although I totally buy into the dense fog and low cloud scenario for the west, that's more or less unavoidable. But I think people will be commenting on the various threads how warm it feels on Thursday, Thursday night and even into Friday, looking at the air mass upstream now between 25 and 35 W out around 50 N the dew points have held near 19 or 20 C (as they were several days ago in this air mass) and of course temperatures out there are not much higher than sea surface values near 21-22 C. This air mass will clearly hit the west coast with a surface layer near 18/18 full of fog and drizzle, but will begin to warm up over land and potentially it could reach 25-27 C if the sun gets through. The warmest part of the wedge is overhead on Friday morning so the morning lows on Friday are likely to feel oppressive (lows of 17-19 C are possible).

Maybe not a heat wave as such, but certainly a warm event of some note, and it stays a bit warmer than average for a few days afterwards, there are hints of a colder turn mid-week but perhaps this will turn out to be rather bland.

lucy2010

M.T. Cranium wrote: »

Good morning, the very warm wedge is approaching ... and I continue to think it has been underpredicted although I totally buy into the dense fog and low cloud scenario for the west, that's more or less unavoidable. But I think people will be commenting on the various threads how warm it feels on Thursday, Thursday night and even into Friday, looking at the air mass upstream now between 25 and 35 W out around 50 N the dew points have held near 19 or 20 C (as they were several days ago in this air mass) and of course temperatures out there are not much higher than sea surface values near 21-22 C. This air mass will clearly hit the west coast with a surface layer near 18/18 full of fog and drizzle, but will begin to warm up over land and potentially it could reach 25-27 C if the sun gets through. The warmest part of the wedge is overhead on Friday morning so the morning lows on Friday are likely to feel oppressive (lows of 17-19 C are possible).

Maybe not a heat wave as such, but certainly a warm event of some note, and it stays a bit warmer than average for a few days afterwards, there are hints of a colder turn mid-week but perhaps this will turn out to be rather bland.

MT what happened on Monday that gave us these bizarre temps of 26/27 c just south of Dublin ?

M.T. Cranium

Lucy, I think the Monday temps were created by three factors acting together. First of all, there was a widespread warming over the south and east that was reflected in the official temperatures in the 23-24 C range (and as of last night, Dublin A was not reporting its daily max, perhaps they have it on the system today). Secondly, the higher temperatures you're mentioning were not overlapped by official readings, so they could have been consistent with those reports. However, some of these readings are taken at non-standard observing sites. This does not mean that the reports are wrong, probably the temperature was what was reported at those locations. But the official sites in Ireland are all well away from urban effects and therefore these micro or meso scale climate factors are not reflected in the official readings. I won't be too surprised if the same thing happens tomorrow, official stations may reach 24-25 C and some other readings may be reported into the 26-28 C range.

As to the micro or meso-scale climate, sometimes near the sea skies are clear while the air mass supports 70-80 per cent cloud cover inland, and yet the sea breeze is so weak that it fails to cool in that cleared zone, hence you have the optimal conditions for warming, an urban environment getting full sunshine. I suspect that may have been the meso-scale explanation for what happened on Monday. There again, the air mass arriving tomorrow is similar, and could produce a similar result. Could be a great beach day around the east and south coasts.

For those reading with some technical knowledge, note the high thickness values being advected in with this warm wedge, reaching about 567 dm. This can support 28-30 C and that's a likely max temp for Friday in parts of inland southern England. So it would not be physically impossible for temperatures to reach almost that level in one or two places in Ireland later afternoon on Thursday. I think the dynamics are such that the fog on the west coast may start to break up and allow even some west coast holiday areas to enjoy some 22-24 C warmth by late afternoon.

I remain rather bullish on the thunderstorm potential for Friday also -- the dynamics look fairly strong for 12-18z with the east and southeast being the more likely regions to see a thunderstorm.

Su Campu

M.T. Cranium wrote: »

As to the micro or meso-scale climate, sometimes near the sea skies are clear while the air mass supports 70-80 per cent cloud cover inland, and yet the sea breeze is so weak that it fails to cool in that cleared zone, hence you have the optimal conditions for warming, an urban environment getting full sunshine. I suspect that may have been the meso-scale explanation for what happened on Monday. There again, the air mass arriving tomorrow is similar, and could produce a similar result. Could be a great beach day around the east and south coasts.

What about Föhn effect warming MT? With plenty of low level stratus covering the Dublin mountains down to a low level recently, it could have drizzled enough moisture to lead to an extra degree or two of adiabatic warming on the leeward side. This may have happened at the Bray airshow on Sunday, where conditions were perfect while further north I was in low cloud and pretty murky conditions. I was actually surprised to hear the airshow went ahead at all!

doccy

Hmm, I don't know about heat waves and such but one thing I definitely feel is the surface water of the Irish sea feels warmer this year. I've swam every summer since I was a little kid and it definitely feels...less cold

gurramok

Its about 14C out now, was a little chilly on that breeze on the hands out walking. Hope it gets a bit warmer later as forecasted to the 28C

pauldry

what country is 28c promised for? England ? No US? Yes

Ireland will reach 23c at best today and only 28c IN THE SUN or more, not in the shade where temperature readings are recorded

Su Campu

Yes, the wedge of tropical air MT referred to is only reaching the west coast this evening, so it will really be tonight and tomorrow when its effects will be most felt.

lucy2010

pauldry wrote: »

what country is 28c promised for? England ? No US? Yes

Ireland will reach 23c at best today and only 28c IN THE SUN or more, not in the shade where temperature readings are recorded

Good to see what we get today remember Trogs weatherstation hit 26.9c on Monday & im a bit up from the sea from him. Im not too bothered on excessive temps just enjoyin the " dryness" for change

delw

ME forcast after 1 o'clock news has ireland with a max of 20c for today

Mobhi1

Yea, can't see us reaching high temps today. Still below 18C in most of the country. The warmest is only 18C in Valentia, nearest the "warm wedge".

Mobhi1

Think we'll be doing well to reach 20C here, anyway!

Domscard

Grey and dull here in east Donegal. The only heatwave I'm getting is when I stand close to the fire

M.T. Cranium

This warm wedge has been underperforming so far, I do notice on satellite imagery that clearing skies have begun to spread further east so it may turn out fairly warm for the evening in the south and possibly the east, but basically the inversion seems to have remained fairly strong despite the high sun angle of July, and given a result more like perhaps November with the thickness pattern. Note, the wedge may be centered further west at present but the 564 dm thickness contour has crossed Ireland with the 570 dm thickness forming a ridge just to the southwest of Kerry now (from the 12z chart just in).

I'll have to see if I can find a logical explanation of the disconnect that took place between thickness and surface temperature, other than marine layer dynamics, because it seems that the temperature has not responded very well over the UK either. It's probably just one of those things where there were two possible outcomes and not enough energy was available to shift the inertial outcome to the dynamic outcome. That may have consequences for tomorrow's forecast, will have to see how the next model run handles that situation.

delw

like you say MT hopefully we get a nice evening however with only a couple of days left in july fingers are crossed for sunny weather in august

gurramok

pauldry wrote: »

what country is 28c promised for? England ? No US? Yes

Ireland will reach 23c at best today and only 28c IN THE SUN or more, not in the shade where temperature readings are recorded

Smart are we?

I've always been lead to believe temp recordings from forecasts are based on been recorded in the shade not in the sun.

Read MT's post of explanation for todays unexpected temp readings.

Had to close the window, its a little cool outside now, no muggy night in store so far!

adamski8

owenc wrote: »

Don't beleive me then you mustn't be too good a geography because it is!

http://en.wikipedia.org/wiki/British_Isles

owenc wrote: »

Yes he is hes trying to deny it because it has the word "british" in it:rolleyes:.... its 9.5c here!:eek:

owenc wrote: »

Hes being sarcastic.:rolleyes::rolleyes:

no i wasn't being sarcastic! hahaha you made me laugh though!
i dont have any problem with the word british.

Su Campu

M.T. Cranium wrote: »

This warm wedge has been underperforming so far, I do notice on satellite imagery that clearing skies have begun to spread further east so it may turn out fairly warm for the evening in the south and possibly the east, but basically the inversion seems to have remained fairly strong despite the high sun angle of July, and given a result more like perhaps November with the thickness pattern. Note, the wedge may be centered further west at present but the 564 dm thickness contour has crossed Ireland with the 570 dm thickness forming a ridge just to the southwest of Kerry now (from the 12z chart just in).

I'll have to see if I can find a logical explanation of the disconnect that took place between thickness and surface temperature, other than marine layer dynamics, because it seems that the temperature has not responded very well over the UK either. It's probably just one of those things where there were two possible outcomes and not enough energy was available to shift the inertial outcome to the dynamic outcome. That may have consequences for tomorrow's forecast, will have to see how the next model run handles that situation.

I don't know but I think it was just too much boundary layer modification as it slowed down over the Atlantic. The 06Z and 12Z FAX charts depict warm frontolysis in a slack flow, which would back this theory up. The 18Z Valentia sounding shows the strong inversion above around 900hPa, capping a well mixed boundary layer containing a 1500ft thick cloud deck. Without this cloud the sounding would suggest a Tmax around mid-high 20s, but the cloud deck ruined it on us. I think it was just too much marine track for it to hold onto its heat

pauldry

gurramok wrote: »

Smart are we?

I've always been lead to believe temp recordings from forecasts are based on been recorded in the shade not in the sun.

Read MT's post of explanation for todays unexpected temp readings.

Had to close the window, its a little cool outside now, no muggy night in store so far!

Not being smart at all. Just giving my opinion. It didnt get at all warm today did it? Yes MT explains it well. Maybe we'll get the 23c tomorrow or even the 28c which would be better again.

It seems to be quite difficult to predict conditions in July in Ireland. One of my friends said .... no its not its just 18 or 19c every day and 12 or 13 at night. Hes right most of the time for Sligo anyways.