UK winter 2019-20

Update 2

13th September 2019

Overview

For the latest view see:

Balance could be changing - Winter 2019/20 update 3, Issued on November 4th 2019

For more context and background information please read:

Winter 2019/20 weather, Long range forecast signals issued on July 30th 2019

 

Grand Union Canal, March 2018

August and September

All months to date this year have recorded an average or above average Central England Temperature (CET). Summer 2019 was warm, although more mixed than last year's. Despite that, the UK's hottest day was recorded on Thursday 25th July when 38.7C was reached at Cambridge Botanic Garden. 

September has been cooler so far. To the 12th the provisional CET is 14.3C which is 0.1C below the 1961-90 average. However, there are indications of warmer than average days during the rest of the month, although nights may often be quite cool.

When producing the winter forecast the September weather patterns are considered. A cool and cyclonic month is counted as a weak factor in favour of a colder winter. On the other hand a warm and anticyclonic month is considered to favour a mild winter.

It is important to emphasise that a correlation between warm Septembers and milder than average winters is not accepted by many, but the TWO view is that it has existed in recent decades.   

Seasonal models

At this early stage most of the long range computer models are suggesting a milder than average winter in the UK.

Model Temperature Precipitation
UK Met Office GloSea (UK) D/J/F Above average Weak bias towards above average
Meteo France (France) D/J/F Above average Close to average
ECMWF D/J/F Above average Average or above average
DWD (Germany) D/J/F Above average Above average
International Research Institute (IRI) D/J/F Above average Above average
Jamstec (Japan) D/J/F Below average in the north, above in the south Above average
C3S multi system (European combi) D/J/F Above average Weak bias towards above average
CFS v2 (USA) D/J/F Below average  Below average
BCC (China) D/J/F Above average Slightly above average

 

D/J/F = December, January, February

The Climate Forecast System v2 is available on TWO. View the latest CFS v2 charts.

{ADVERT}

Indexes and teleconnections

See the July update for more background information.

North Atlantic Oscillation (NAO)

This year the likelihood of a neutral is considered to be higher than the norm.

Quasi-biennial oscillation (QBO)

The QBO switched to a positive phase in November 2018. The mean period of each phase is 28 or 29 months, so there is a high likelihood of it staying positive through the winter. If that happens, it would be a factor supportive of a milder winter.

Berkhamsted snow drifts,  March 2018

El Niño Southern Oscillation (ENSO)

Forecasting the ENSO conditions several months ahead is prone to error, but at the moment El Nino is favoured to be neutral through the Northern Hemisphere winter.

Solar Activity

The coming winter is expected to coincide with the minimum in Solar Cycle 24. Thereafter activity is expected to steadily recover as Solar Cycle 25 begins.

Summary

It is too early for a clear signal for winter 2019/20 to emerge. Recent climatology favours milder conditions as do most of the seasonal forecasts models. However not all of the background signals offer support for this scenario. 

At this stage the TWO view is the balance of evidence weakly supports a milder than average winter.

From Brian Gaze, TWO founder
Since establishing TheWeatherOutlook over 15 years ago the site has grown enormously and running costs have risen. I intend to continue expanding TWO and keeping it free if possible. If you find it useful and would like to contribute to its development please consider making a donation.

Regular updates will be issued before the TWO winter forecast is released at the end of November.

Press and media enquiries

We welcome all press enquiries, whether relating to this news feature, or seeking comment on other weather news.

Contact us

News and information

RECENT WEATHER NEWS



COMPUTER MODELS

INFO

Short range
Short to medium range
Medium to long range
Deterministic
Ensemble

See the Model inventory for the full list of model charts and data