Storm Francis - 24th/25th August 2020

12z ECM out in the next hour or so. MÉ more likely to take any naming decisions based on that and Harmonie.

On the contrary, ECM not convinced yet. But a slight upgrade on its part nonetheless.

I wouldn't like to be the one calling this one. I'd say they probably will, eventually, given all the recent rainfall, wind and the potential that the ground is sodden and trees will already be weakened as well as in full leaf.

The 146km/h mark can be discounted as it's 3,000ft in the air.
Generally gusts struggling to 110km/h or to a mean of 65km/h over land.
Rainfall 6h/24h also barely just almost at Orange levels. (45-50mm/24h - Orange would be 50mm/24h + )

Analysis at 18Z has it 1010 hPa at 44N 40W, slightly higher than forecast yesterday. Water vapour image for the same time. The low centre is located just north of that darkest green blob near the centre of the image.





UKMO Fax shows slightly stronger gradient winds along the west and south coasts. The centre will be travelling at around 40 kph so it will be a fairly quick period of maximum winds. Out at the current centre the total precipitable water is 50-55 mm, so plenty to generate those high rainfall totals, especially on southeast-facing upslopes, such as in Kerry, Cork and Wicklow.

Meteorite58 wrote: »

Met Office


Tues 01.00

This does not look to dissimilar to the pattern which brought some record-breaking rainfall totals to the SW back in August 1986. Syran spoke of this event just recently in fact.

https://modeles.meteociel.fr/modeles/gfs/runs/2020082318/gfs-0-42.png?18
Tonight's gfs is upgrading a nudge
Orange territory now for wind South of the centre
If that ain't a storm I dunno what is!

I certainly agree with everything posted about this event, but just wanted to add that readers in many parts of the country, in particular central Leinster, are going to experience a fairly prolonged interval of light winds due to the shape and trajectory of this low, as it tracks through counties from about Clare to Dublin/Meath, so please don't come on slagging forecasters about the absence of the predicted alert level winds, those are most likely to affect Munster and south Leinster and only late in the event will they start to blow in more moderate intensity across central counties in the wake of the departing storm.

Flooding rather than wind damage may be the main story here. Cork could be in for bad flooding again, Bray in Wicklow has flooded several times in recent memory too and may be vulnerable again tomorrow into Wednesday. Just two examples that spring to my mind when looking at those fax charts.

Supercell wrote: »

Flooding rather than wind damage may be the main story here. Cork could be in for bad flooding again, Bray in Wicklow has flooded several times in recent memory too and may be vulnerable again tomorrow into Wednesday. Just two examples that spring to my mind when looking at those fax charts.

I agree, I think the potential mod to high rainfall totals in parts of the south will be the bigger story from this system.

Dublin added to the warning

Status Yellow - Wind warning for Munster, Dublin, Wexford and Wicklow

Met Éireann Weather Warning

Very windy or stormy conditions are expected on Tuesday as Storm Francis crosses Ireland. Southwest winds veering westerly, reaching mean speeds of 55 to 65km/h, will bring widespread severe gusts of 90 to 110km/h (and possibly higher in exposed areas). Some disruption is likely and possibly structural damage.

Valid: 06:00 Tuesday 25/08/2020 to 19:00 Tuesday 25/08/2020

Issued: 10:55 Monday 24/08/2020

Rainfall Warnings Updated

Status Yellow - Rainfall warning for Dublin, Carlow, Kildare, Kilkenny, Laois, Longford, Louth, Wicklow, Offaly, Westmeath, Meath, Clare, Limerick and Tipperary

Met Éireann Weather Warning

Intense rainfall associated with Storm Francis is expected at times Monday night and Tuesday, leading to accumulations of 30 to 50mm with surface flooding.

This rainfall will further elevate river levels and may result in river flooding also.

Valid: 21:00 Monday 24/08/2020 to 21:00 Tuesday 25/08/2020

Issued: 11:02 Monday 24/08/2020

Yes GL i see a Yellow warning now for rain fall for much of the midland counties now. Do you believe the centre of the Low will stay the course predicted?

I'll take what the Ecm is showing tomorrow morning

Yes, I remember the flooding in Duleek from ex-Charly in 1986. Very similar type of system (Shapiro Keyser) and loads of water in it, though probably a lot more than Francis will have.

1985, 1986...great years for severe weather as a young lad growing up.