Storm Lorenzo: October 3/4 2019 Technical Discussion Only

Meteorite58 · 01-10-2019 8:52pm

ARPEGE 12Z again strongest winds in the W / NW . Track crossing the country a bit further N

JanuarySnowstor · 01-10-2019 8:53pm

It seems we have clear agreement now on landfall close to Sligo coast. My view on warnings are as follows,
Red for Galway, Mayo,Sligo & Done gal
Orange for counties bordering these four
Yellow for rest of country such as Dublin, Limerick and Cork.
A bit like Ophelia very severe for the red areas as above (though Ophelia was the south) and standard blustery day for yellow warning areas.
Rainfall doesn't look an issue to me at all

Oneiric 3 · 01-10-2019 8:53pm

I wonder will we beat the 79 knots recorded during 'Storm Ali' last September (2018)?

Gaoth Laidir · 01-10-2019 8:58pm

UK 12Z FAX charts. It deepens from 968 to 957 hPa early Thursday, then slows down and fills again to 974 hPa just off the west coast by midnight Thursday, but need to watch for a sting jet along that trailing occlusion by then.

Meteorite58 · 01-10-2019 8:58pm

Oneiric 3 wrote: »

I wonder will we beat the 79 knots recorded during 'Storm Ali' last September (2018)?

Doubt it but if we did I would reckon Mace head perhaps.

Oneiric 3 · 01-10-2019 8:59pm

Mr. T. Not sure if it is a browser issue but I can rarely get to see the charts you post.

Example:

Can see charts other peoples post, but not yours, except maybe the odd time.

Meteorite58 · 01-10-2019 9:04pm

One thing the charts are showing is steady strong wind overland also. The models showing widespread gusting up around 90 km/h.

ARPEGE in particular showing it quite strong overland and gusting 90 to 100 km/h in the E up until late morning early afternoon on Fri.

Meteorite58 · 01-10-2019 9:07pm

Oneiric 3 wrote: »

Mr. T. Not sure if it is a browser issue but I can rarely get to see the charts you post.

Can see charts other peoples post, but not yours, except maybe the odd time.

Can see them fine always, browser issue perhaps.

Gaoth Laidir · 01-10-2019 9:07pm

Oneiric 3 wrote: »

Mr. T. Not sure if it is a browser issue but I can rarely get to see the charts you post.

Example:

Can see charts other peoples post, but not yours, except maybe the odd time.

Strange. They're from the Icelandic ftp site. Here's the link

HarshOstrich · 01-10-2019 9:14pm

Most likely there will be countrywide orange weather warning with red warnings for the western coastal counties.

FastFullBack · 01-10-2019 9:20pm

HarshOstrich wrote: »

Most likely there will be countrywide orange weather warning with red warnings for the western coastal counties.

Will the warnings be out tonight? Or more likely tomorrow morning?

M.T. Cranium · 01-10-2019 9:21pm

Nothing settled yet but high alert status is certainly warranted.

Gaoth Laidir · 01-10-2019 9:21pm

12Z ECM ensembles very clustered, especially the intensity, which matches the HRES remarkably well. It has a reintensification to 80 knots tomorrow after it moves away from the Azores, then a second peak off to the west of Ireland. That would hint at a sting jet.

ps2png-gorax-blue-007-6fe5cac1a363ec1525f54343b6cc9fd8-UCdkeQ.png

ps2png-gorax-blue-007-6fe5cac1a363ec1525f54343b6cc9fd8-UCdkeQ.png

UpTheHillFrom · 01-10-2019 9:24pm

FastFullBack wrote: »

Will the warnings be out tonight? Or more likely tomorrow morning?

Press conference tomorrow at 12 noon.

m17 · 01-10-2019 9:33pm

SleetAndSnow · 01-10-2019 9:38pm

High tide was very high in cork city both yesterday and today, with yesterday causing the Lee to flood parts of the city. Lorenzo sea surge + high tide is more of risk then rainfall rates id say as they seem to coincide at the same time.

JanuarySnowstor · 01-10-2019 9:41pm

Worth bearing in mind sea surge is likely to be ahead of the storm so may cause issues as early as tomorrow nights high tide

Oneiric 3 · 01-10-2019 9:43pm

EPS probability chart for Thurs noon firming up now. (850 hPa wind speeds > 50 knots)

Still plenty of scope for change though. In storm watching terms, 48hrs out is still too far out to pin down any specific solution with any degree of confidence.

Edit: Nearly a 1000 people watching this thread right now. That must be a near record!

Snow Garden · 01-10-2019 9:43pm

SleetAndSnow wrote: »

High tide was very high in cork city both yesterday and today, with yesterday causing the Lee to flood parts of the city. Lorenzo sea surge + high tide is more of risk then rainfall rates id say as they seem to coincide at the same time.

Very high tide tonight in Galway - 5.5m but its down to 4.6m on Friday.

Kermit.de.frog · 01-10-2019 9:45pm

Whilst conceivably a red warning could be warranted anywhere for various reasons (flooding, wind strength, sea surge) most likely we are talking about the western Atlantic facing counties.

I don't think Dubs have much reason to be concerned that they won't be able to go to work.

TTLF · 01-10-2019 9:48pm

Kermit.de.frog wrote: »

Whilst conceivably a red warning could be warranted anywhere for various reasons (flooding, wind strength, sea surge) most likely we are talking about the western Atlantic facing counties.

I don't think Dubs have much reason to be concerned that they won't be able to go to work.

the only thing i see bad for dubs is the wind/rain making trees fall due to saturated ground

also the possibility of flooding due to already high rivers

but that's a typical storm.

SleetAndSnow · 01-10-2019 9:51pm

Advisory 38:

PokeHerKing · 01-10-2019 9:52pm

JanuarySnowstor wrote: »

It seems we have clear agreement now on landfall close to Sligo coast. My view on warnings are as follows,
Red for Galway, Mayo,Sligo & Done gal
Orange for counties bordering these four
Yellow for rest of country such as Dublin, Limerick and Cork.
A bit like Ophelia very severe for the red areas as above (though Ophelia was the south) and standard blustery day for yellow warning areas.
Rainfall doesn't look an issue to me at all

From game over to county specific landfall!

Gaoth Laidir · 01-10-2019 9:55pm

Latest discussion.

500 PM AST Tue Oct 01 2019

The eye of Lorenzo, while still evident in both visible and infrared
satellite imagery, has become smaller and slightly less distinct
this afternoon, but the overall structure of the hurricane has not
changed much since the previous advisory. Objective Dvorak
T-numbers crept up this morning when the eye cleared for a couple
of hours and are somewhat higher than the latest subjective
estimates from TAFB and SAB. A blend of these estimates remains
around 85 kt, and this is the value used as the initial wind speed
for this advisory. Lorenzo is heading toward colder waters and an
area of increasing vertical wind shear. However, since the wind
field of the hurricane is quite large, only gradually weakening is
foreast during the next 12 to 24 hours. After that time, Lorenzo
is forecast to merge with a front and become a strong extratropical
low over the northeastern Atlantic. The global models indicate
that the post-tropical low will weaken more quickly when it moves
near Ireland and Great Britain in 2 to 3 days.

Lorenzo continues to accelerate northeastward, with an initial
motion estimate of 040/25 kt. The forward speed of the hurricane
is predicted to increase further overnight and on Wednesday as it
is steered northeastward ahead of a mid-latitude trough over the
central Atlantic. By late Thursday, the post-tropical cyclone
should slow down and turn eastward or east-southeastward within the
low-level westerly flow. The track has continued to bend to the
right beyond 48 hours, and the official forecast has once again
been adjusted southward and eastward at that time period. The new
NHC track forecast is in good agreement with the latest ECMWF model.

Lorenzo is producing very large seas over the north Atlantic. Full
information can be found in High Seas Forecasts from the following
agencies:

The NOAA Ocean Prediction Center under AWIPS header NFDHSFAT1, WMO
header FZNT01 KWBC, and online at
ocean.weather.gov/shtml/NFDHSFAT1.php

The UK Met Office under WMO header FQNT21 EGRR and online at
http://www.metoffice.gov.uk/public/weather/marine-high-seas/

Meteo France under WMO header FQNT50 LFPW and online at
http://www.meteofrance.com/previsions-meteo-marine/bulletin/
grandlarge/metarea2

Key Messages:

1. Lorenzo is expected to bring hurricane and tropical storm force
winds to the Azores beginning tonight, and these conditions
will continue into Wednesday. Hurricane and Tropical Storm Warnings
are in effect for the Azores.

2. Swells generated by Lorenzo have spread across much of the
North Atlantic, and are affecting the east coast of the United
States, Atlantic Canada, the Bahamas, portions of the Greater and
Lesser Antilles, and portions of the coast of Europe. These swells
will produce life-threatening surf and rip currents.

FORECAST POSITIONS AND MAX WINDS

INIT 01/2100Z 37.0N 35.5W 85 KT 100 MPH
12H 02/0600Z 40.2N 31.3W 80 KT 90 MPH
24H 02/1800Z 45.6N 24.8W 70 KT 80 MPH
36H 03/0600Z 51.2N 18.4W 65 KT 75 MPH...POST-TROP/EXTRATROP
48H 03/1800Z 54.4N 13.5W 60 KT 70 MPH...POST-TROP/EXTRATROP
72H 04/1800Z 53.2N 3.0W 35 KT 40 MPH...POST-TROP/EXTRATROP
96H 05/1800Z...DISSIPATED

JanuarySnowstor · 01-10-2019 10:08pm

Rapid deepening of Lorenza on th 18z Icon. The Northwest and North of Ireland are going to experience hurricane type weather if this comes off.

m17 · 01-10-2019 10:11pm

SleetAndSnow · 01-10-2019 10:20pm

Latest ICON. Looks slightly further north, slightly slower to cross the country. Looks slightly weaker too.

Will be really hard to tell if this goes north or south, models keep flipping.

sdanseo · 01-10-2019 10:20pm

JanuarySnowstor wrote: »

Rapid deepening of Lorenza on th 18z Icon. The Northwest and North of Ireland are going to experience hurricane type weather if this comes off.

There's barely a red warning on the 18Z Icon going by wind speed. Maybe western counties will get red on merit.

Let alone anything resembling 64kt + mean winds.

It's as we were.

froog · 01-10-2019 10:22pm

are we looking at more destructive impact to ireland than ophelia at this stage? or about the same?

SleetAndSnow · 01-10-2019 10:22pm

froog wrote: »

are we looking at more destructive impact to ireland than ophelia at this stage? or about the same?

Neither. Less i'd say.

Storm Lorenzo: October 3/4 2019 **Technical Discussion Only**

Comments

Storm Lorenzo: October 3/4 2019 Technical Discussion Only