Met office Contingency planners forecasts

[Don]

2 minutes ago, Summer Sun said:

February update

March to May

Temperature summary

For March-April-May as a whole, above-average temperatures are more likely than below-average temperatures. Overall, the probability that the UK-average temperature for March-April-May will fall into the coldest of our five categories is less than 5% and the probability that it will fall into the warmest of our five categories is around 55% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-mam-v2.pdf

Precipitation summary

For March-April-May as a whole, above-average precipitation is slightly more likely than below-average precipitation. The probability that UK-average precipitation for March-April-May will fall into the driest of our five categories is around 15% and the probability that it will fall into the wettest of our five categories is 25% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-precip-mam-v2.pdf

The strong signal for above average temperatures continues, with a slight bias towards wetter than average conditions, too.  However, at least it should be less wet than what we've experienced recently.

[Summer Sun]

March update

April to June

Temperature summary

For April, above-average temperatures are slightly more likely than below-average temperatures. For April-May-June as a whole, above average temperatures are more likely than below-average temperatures. Overall, the probability that the UK-average temperature for April-May-June will fall into the coldest of our five categories is less than 5% and the probability that it will fall into the warmest of our five categories is between 40 and 45% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-amj-v1.pdf

Precipitation summary

For April, the likelihoods of above- and below-average precipitation are similar. For April-May-June as a whole, below-average precipitation is moderately more likely than above-average precipitation. The probability that UK-average precipitation for April-May-June will fall into the driest of our five categories is 25% and the probability that it will fall into the wettest of our five categories is around 15% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-precip-amj-v1.pdf

 

[johnholmes]

Warm and fairly dry?

[Don]

1 hour ago, johnholmes said:

Warm and fairly dry?

Yes and some dry weather would be welcome following a very wet winter and good for the current situation!

[Summer Sun]

April update

May to July

Temperature summary

For May-June-July as a whole, above-average temperatures are more likely than below-average temperatures. Overall, the probability that the UK-average temperature for May-June-July will fall into the coldest of our five categories is between 5% and 10%, and the probability that it will fall into the warmest of our five categories is between 50% and 55% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-mjj-v2.pdf

Precipitation summary

For May-June-July as a whole, below-average precipitation is more likely than above-average precipitation. The probability that UK-average precipitation for May-June-July will fall into the driest of our five categories is around 30% and the probability that it will fall into the wettest of our five categories is 10% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-precip-mjj-v2.pdf

[Summer Sun]

May update

June to August

Temperature summary

For June-July-August as a whole, above-average temperatures are more likely than below-average temperatures. Overall, the probability that the UK-average temperature for June-July-August will fall into the coldest of our five categories is less than 5%, and the probability that it will fall into the warmest of our five categories is around 50% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-jja-v2.pdf

Precipitation summary

For June-July-August as a whole, below-average precipitation is slightly more likely than above-average precipitation. The probability that UK-average precipitation for June-July-August will fall into the driest of our five categories is 25% and the probability that it will fall into the wettest of our five categories is between 15% and 20% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-precip-jja-v2.pdf

[Don]

1 hour ago, Summer Sun said:

May update

June to August

Temperature summary

For June-July-August as a whole, above-average temperatures are more likely than below-average temperatures. Overall, the probability that the UK-average temperature for June-July-August will fall into the coldest of our five categories is less than 5%, and the probability that it will fall into the warmest of our five categories is around 50% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-jja-v2.pdf

Precipitation summary

For June-July-August as a whole, below-average precipitation is slightly more likely than above-average precipitation. The probability that UK-average precipitation for June-July-August will fall into the driest of our five categories is 25% and the probability that it will fall into the wettest of our five categories is between 15% and 20% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-precip-jja-v2.pdf

Another strong signal for warmer than average temperatures this summer with a smaller bias towards drier than average conditions.

[Summer Sun]

June update

July to September

Temperature summary

For July-August-September as a whole, above-average temperatures are more likely than below-average temperatures. Overall, the probability that the UK-average temperature for July-August-September will fall into the coldest of our five categories is around 10%, and the probability that it will fall into the warmest of our five categories is around 45% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-jas-v2.pdf

Precipitation summary

For July-August-September as whole, above-average precipitation is slightly more likely than below-average precipitation. The probability that UK-average precipitation for July-August-September will fall into the driest of our five categories is between 20% and 25% and the probability that it will fall into the wettest of our five categories is 25% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-precip-jas-v2.pdf

[Don]

47 minutes ago, Summer Sun said:

June update

July to September

Temperature summary

For July-August-September as a whole, above-average temperatures are more likely than below-average temperatures. Overall, the probability that the UK-average temperature for July-August-September will fall into the coldest of our five categories is around 10%, and the probability that it will fall into the warmest of our five categories is around 45% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-jas-v2.pdf

Precipitation summary

For July-August-September as whole, above-average precipitation is slightly more likely than below-average precipitation. The probability that UK-average precipitation for July-August-September will fall into the driest of our five categories is between 20% and 25% and the probability that it will fall into the wettest of our five categories is 25% (the 1981-2010 probability for each of these categories is 20%).

Full forecast: https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-precip-jas-v2.pdf

No surprises there with regards to temperatures expected to be above average overall.

[Summer Sun]

The CPF is back in a brand-new format

The winter summary is as follows;

1. More than double the chance of a wet winter compared to normal
2. Increased likelihood of impacts from heavy rainfall and wind
3. A near average winter remains possible, with a dry winter least likely
4. Large reduction in the chance of a cold winter compared to normal
5. Decreased likelihood of impacts from cold weather such as snow, frost and fog
6. A cold spell remains possible even in a near average or mild winter

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-djf-v2.pdf

Edited December 1, 2020 by Summer Sun

[Eskimo]

1 hour ago, Summer Sun said:

The CPF is back in a brand-new format

The winter summary is as follows;

1. More than double the chance of a wet winter compared to normal
2. Increased likelihood of impacts from heavy rainfall and wind
3. A near average winter remains possible, with a dry winter least likely
4. Large reduction in the chance of a cold winter compared to normal
5. Decreased likelihood of impacts from cold weather such as snow, frost and fog
6. A cold spell remains possible even in a near average or mild winter

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-djf-v2.pdf

Oh well, MetOffice says mild/wet Winter, that's us getting a 1963 redux then 

[Beanz]

2 hours ago, Summer Sun said:

The CPF is back in a brand-new format

The winter summary is as follows;

1. More than double the chance of a wet winter compared to normal
2. Increased likelihood of impacts from heavy rainfall and wind
3. A near average winter remains possible, with a dry winter least likely
4. Large reduction in the chance of a cold winter compared to normal
5. Decreased likelihood of impacts from cold weather such as snow, frost and fog
6. A cold spell remains possible even in a near average or mild winter

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-djf-v2.pdf

That is the output of somebody who doesn’t actually have a clue what the winter period will be like, so they covered just about every angle they could.  
 

“It won’t be cold, but it will be average but at some points it could be colder than average, but generally it’s most likely it will be average, and wet...probably” 

[Mapantz]

11 minutes ago, Beanz said:

That is the output of somebody who doesn’t actually have a clue what the winter period will be like, so they covered just about every angle they could.  
 

“It won’t be cold, but it will be average but at some points it could be colder than average, but generally it’s most likely it will be average, and wet...probably” 

I say this every year, but I'll say it again anyway. You're misinterpreting it.

[Beanz]

8 minutes ago, Mapantz said:

I say this every year, but I'll say it again anyway. You're misinterpreting it.

That’s what my wife says too  

[DAVID SNOW]

Does it say which month is the most likely to be impacted by heavy rain and strong winds, also does it say which month has a low chance of a cold spell?

 

[johnholmes]

4 hours ago, Beanz said:

That is the output of somebody who doesn’t actually have a clue what the winter period will be like, so they covered just about every angle they could.  
 

“It won’t be cold, but it will be average but at some points it could be colder than average, but generally it’s most likely it will be average, and wet...probably” 

A silly remark about a professional output if I may so

[Beanz]

25 minutes ago, johnholmes said:

A silly remark about a professional output if I may so

Lighten up John

[Summer Sun]

December update

1. Higher-than-normal chance of wet conditions
2. Increased likelihood of impacts from heavy rainfall and wind
3. Near average or dry conditions remain possible
4. Large reduction in the chance of cold conditions compared to normal
5. Decreased likelihood of impacts from cold weather such as snow, frost and fog
6. Cold spells remain possible even in a near average or mild 3-month period

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-jfm-v1.pdf

[northwestsnow]

I've just referenced this ...

Not pleasant reading...

Was this written before the ssw Glosea is now seeing?

[Uncertainty]

9 minutes ago, northwestsnow said:

I've just referenced this ...

Not pleasant reading...

Was this written before the ssw Glosea is now seeing?

I think they’ve taken the poss SSW into account NWS, they’ve referenced a possible weaker SPV in the outlook and weighed it up against the moderate late winter Nina background (weaker MJO?) and unfavourable Atlantic SSTs. The latter did us no favours in Jan 2019...

In all fairness it’s a lot better than the last update which was horrific for cold or dry conditions. They do mention an increased chance of a colder Jan vs the last few years. Still a low chance mind.

The latest seasonal output for JFM won’t be available to them yet, they can’t ignore the westerly dominance the seasonals currently show based solely on the hypothetical effects of a downwelling SSW that doesn’t exist yet. 
 

But we can

[northwestsnow]

1 minute ago, Uncertainy said:

I think they’ve taken the poss SSW into account NWS, they’ve referenced a possible weaker SPV in the outlook and weighed it up against the moderate late winter Nina background (weaker MJO?) and unfavourable Atlantic SSTs. The latter did us no favours in Jan 2019...

In all fairness it’s a lot better than the last update which was horrific for cold or dry conditions. They do mention an increased chance of a colder Jan vs the last few years. Still a low chance mind.

The latest seasonal output for JFM won’t be available to them yet, they can’t ignore the westerly dominance the seasonals currently show based solely on the hypothetical effects of a downwelling SSW that doesn’t exist yet. 
 

But we can

Strange thing is the long ranger updated today has the first half of Jan cold.

 

[Mapantz]

Just now, northwestsnow said:

Strange thing is the long ranger updated today has the first half of Jan cold.

 

I would ignore it to a certain extent, and by that, I mean us, the general public.

Every year, it causes all kinds of panic and dismissal. 

The important thing on that list, is #6.

[Summer Sun]

September update

October to December

• The period is significantly more likely than normal to be mild
• Despite this, cold spells are still possible, especially during November and December
• The period is slightly more likely than normal to be wet

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-ond-v2-secure.pdf

[damianslaw]

9 hours ago, Summer Sun said:

September update

October to December

• The period is significantly more likely than normal to be mild
• Despite this, cold spells are still possible, especially during November and December
• The period is slightly more likely than normal to be wet

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-ond-v2-secure.pdf

Significantly more likely to be mild, but cold spells still possible.. might see a few shots of arctic air then.. with high pressure to the west, but quickly toppled by milder atlantic air invading around NW flank of the heights - its not a bad place to be if looking for something more substantively colder, the ridge may build further north than anticipated and block the atlantic.. but at the same time, 1-2 day northerly topplers don't float cold snow lover's boat. This is just one possible option..  the cold spells could come from cyclonic conditions, but it doesn't suggest anything from antiyclonic or easterly.. reference to more likely to be wetter, but does say only slightly. Again this doesn't suggest an atlantic rain fest either, with SW/W airstreams.

[Summer Sun]

October update

November to January

• A mild 3-month period is more likely than a cold one
• However, cold weather-related impacts, such as snow, remain possible
• These impacts are more likely during the first half of the period
• Higher than normal chance of wet conditions
• Increased likelihood of impacts from heavy rainfall and strong winds, especially later in the period

 

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-ndj-v1secure.pdf