Extratropical Storm Ophelia - Technical Analysis Only - MOD NOTE post #1

Meteorite58

Mod Note : Reminder that there is a chat thread re preparations / disruptions, see below . Best keep this thread for more technical discussion.

Thanks for your cooperation.

http://www.boards.ie/vbulletin/showthread.php?t=2057797471

JCX BXC

Captain Snow wrote: »

Cat 2 Hurricane is a deadly weather event. This cant be stressed enough. Stay inside on Monday and Tuesday. There is going to be a lot of destruction. Stay safe.

Tuesday should be fine, storm will have well moved off by then.

Captain Snow

thomasj wrote: »

It won't be a hurricane

We,ll see as it approaches. Have had a few close calls in the Dominican Republic.
Never under estimate the weather.

Oscar Bravo

Picky owner wrote: »

I don't really understand ,what is the purple or red on the charts,which is more stronger,am in Waterford.

Hey picky owner, if you look at bottom of chart there is a colour key. just follow that, should give you an idea.

allthedoyles

https://www.facebook.com/OviedoWeatherReports/videos/1182623978479519/

This video explains the categories

Samaris

Picky owner wrote: »

I don't really understand ,what is the purple or red on the charts,which is more stronger,am in Waterford.

Look at the legend at the bottom - red is intenser than blue/green, dark red is more intense then through purple shades to white is jesus christ, I'm hiding under the bed.

It is more technical and with numbers in the chart though :P

Pherekydes

Picky owner wrote: »

I don't really understand ,what is the purple or red on the charts,which is more stronger,am in Waterford.

There is a scale on the bottom of the chart. Match the colour on the chart with the colour on the scale. Basically, red is bad, purple is really bad, and you want to be in shelter when it turns mauve.

fryup

thomasj wrote: »

The last guidance I saw from the national hurricane centre said storm force as opposed to hurricane force.

take a look at this

thomil

thomasj wrote: »

The last guidance I saw from the national hurricane centre said storm force as opposed to hurricane force.

Quote from NHC Public Advisory #25 on Hurricane Ophelia:


HAZARDS AFFECTING LAND

---

WIND: Gale-force winds are expected to begin across southern
Ireland by early Monday morning and gradually spread northward
across the country during the day. Hurricane-force winds are
expected to reach the southern portions of Ireland by Monday
afternoon and spread inland across the country into Monday night.
Preparations to protect lives and property should be rushed to
completion by this afternoon.


Here's the link:

http://www.nhc.noaa.gov/text/refresh/MIATCPAT2+shtml/150840.shtml

So yes, it will come in with hurricane force winds if the current forecast holds.

Now, could someone lend me a hand? There's an ark in my backyard that needs to be finished...

Supercell

Looking at the fax charts it would seem that the strongest winds will be southerly initially and veering westerly, hopefully the Wicklow mountains will prove some shelter to Dublin as usual if that is the case, nonetheless a slightly scary setup and one not to be ignored.

At 10am. Beginnings of degradation from a tropical system. Distorted eye just about visible.

server down

pad199207 wrote: »

Latest from Joanna

“Latest update; transition to ex-tropical status in construction. maintaining hurricane force winds. Likely to hit with cat2 strength.”

Jesus.

BumperD

flazio wrote: »

These news websites take into account where you are logging in from and display news they feel is most relevant to you.
Someone logging in to CNN from New Zealand might not even have that on the page.

I live in Central America direction without being too specific.. It's the top news item on our CNN edition. It will be an event where ever it strikes but thankfully fast moving. East and north east of centre, think 2-5pm of a clock if you are looking at a clock , that's where the strongest winds are always packing.

Meteorite58

GFS 06Z out now

Looks really bad all along the S Coast during landfall.

Mean speeds




Gusts

511

fryup wrote: »

but, you'll have hurricane force gusts

Actually, it's cat 2 hurricane-strength sustained winds. Hurricanes are measured by their sustained winds over a 1 min period.

Cloudio9

Looks like Mayo is probably no longer Red but counties to the south and east of it will be Red.

Kind of validates Met E's decision not make a call >48 hours out.

Toxica

ngunners wrote: »

Is it just me or does this link lead back to this thread?

This is the chat thread http://www.boards.ie/vbulletin/showthread.php?t=2057797471

Captain Snow

Direct Hit

server down

So a storm with the equivalent of a category 2. How does that rate historically?

fraxinus1

Still no change in the counties with red alerts. Looking at the maps I don't see why more eastern counties are not red. Donegal, Leitrim, Mayo and Sligo will probably be just about yellow level.

Meteorite58

AROME 06Z coming out. looks like a slight shift E

Mean




Gusts

Cloudio9

fraxinus1 wrote: »

Still no change in the counties with red alerts. Looking at the maps I don't see why more eastern counties are not red. Donegal, Leitrim, Mayo and Sligo will probably be just about yellow level.

They probably will be but it's not just a case of flicking a switch to red and back to orange as things evolve..

Red warning kicks off a chain of events with local authorities, schools etc in the affected counties.

Oneiric 3

Cloudio9 wrote: »

Looks like Mayo is probably no longer Red but counties to the south and east of it will be Red.

Kind of validates Met E's decision not make a call >48 hours out.

ECM model, which is one of the main models they use, still shows the potential for a small area of strong winds to move up the west coast for a time tomorrow, which I guess is causing them headaches, since all other models have the low moving inland, killing off this potential. EC will probably fall in line on the 12z run later.

munsterlegend

Meteorite58 wrote: »

AROME 06Z coming out. looks like a slight shift E

Mean




Gusts

Perhaps a trend developing. it has definitely moved a little bit.

TheMilkyPirate

GFS seems to have the strongest gusts in the south between 2-3pm tomorrow afternoon yet the harmonie-arome model above has it as between 5-7pm? Any reason why

MJohnston

Meteorite58 wrote: »

AROME 06Z coming out. looks like a slight shift East

To clarify, do you mean a slight shift compared to the last AROME run, of compared to the consensus track?

Meteorite58

Outside view of events to unfold.

mirrorwall14

Meteorite58 wrote: »

Outside view of events to unfold.

I’m thoroughly confused by the reaction of the Irish Media versus the international media. Is there a possibility of anything Met Eireann are seeing that we aren’t that could explain the laid back “school buses are cancelled” coverage?

Meteorite58

MJohnston wrote: »

To clarify, do you mean a slight shift compared to the last AROME run, of compared to the consensus track?

To me both the the GFS and AROME have shifted E slightly since their last runs.

JCX BXC

12pm TAF (Terminal Area Forecast) issued. Makes for some fun reading! (If you're a duck.... maybe)

Dublin

Regular
BECMG 1608/1610 12015G26KT
BECMG 1610/1612 16025G35KT

Decoded
9am-11am, wind 120 degrees (E) 15kts gusting to 26kts
11am-1pm wind 160 degrees (SE) 25kts gusting to 35kts

Shannon

Regular
BECMG 1605/1607 06025G35KT
BECMG 1609/1612 12035G55KT

Decoded
6am-8am, wind 060 degrees (NE) 25G35KT
9am-12pm wind 120 degrees (E) 35G55KT

Cork

Regular
BECMG 1603/1606 07020G30KT
BECMG 1607/1609 17030G45KT
BECMG 1609/1611 17040G60KT

Decoded
4am-7am wind 070 degrees (NE) 20kts gusting 30kts
8am-10am wind 170 degrees (S) 30kts gusting to 45kts
10am-12pm wind 170 degrees (S) 40kts gusting to 60kts

Knock

Regular
BECMG 1608/1610 08025G35KT
BECMG 1610/1612 12030G40KT

Decoded
9am-11am wind 080 degrees (E) 25kts gusting to 35kts
11am- 1pm wind 120 degrees (E) 30kts gusting to 40kts

*----*----*----*----*----*----*----*----*----*----*

Expect disruption.

Shannon and Cork coming in with the highest gusts early on, 55kts and 60kts respectively. With that forecast only valid to 1pm, we can expect stronger gusts to be forecast in the 6pm TAF.