Storm Francis - 21 August 2020

[Andee]

While August is usually remembered for sunshine, thunderstorms, and the occasional heatwave, in 2020 Britain was battered by something unusual for late summer, a full-blown Atlantic storm. Storm Francis struck on 21 August 2020, bringing with it some of the most unseasonably strong winds and heavy rainfall ever recorded in August.

The Weather Setup

In mid-August 2020, the Atlantic jet stream strengthened and shifted southwards, driving a deep area of low pressure straight across the UK. Unusually for the time of year, the low intensified rapidly as it approached Ireland and the western coasts of Britain.

The Met Office named the system Storm Francis, highlighting the risk of severe impacts from both wind and rain. For August, the storm’s depth and intensity were exceptiona, more typical of an autumn or winter system than high summer.

The Storm Strikes

On 21 August, Francis made its presence felt:

Wind Gusts: Exposed coastal areas of Wales and southwest England saw gusts of 50–60 knots (58–69 mph), with inland gusts of 40–50 mph in places. In Northern Ireland, gusts topped 70 mph in a few locations.

Rainfall: Parts of Wales and northern England were drenched with 50–90 mm of rain in less than 24 hours, leading to rivers rising rapidly and localised flooding.

Seas: Large waves battered western coastlines, causing dangerous conditions and warnings for shipping and ferry routes.

Impacts on the Ground

Despite arriving outside the traditional storm season, Francis caused significant disruption:

Trees still in full leaf were especially vulnerable, leading to fallen branches and blocked roads.

Power cuts were reported in parts of Wales and southwest England.

Rail services were disrupted as debris littered tracks and overhead lines were damaged.

Flood alerts were issued across Wales and northern England after rivers burst their banks.

Thankfully, there were no widespread fatalities, but the storm served as a reminder that severe weather can strike at any time of year.

Why It Matters

August storms are relatively rare in the UK, and when they do strike, their impacts can be amplified because the natural environment is in full summer mode, trees in leaf, rivers running low but quick to rise, and many people outdoors.

Storm Francis followed quickly after Storm Ellen, marking one of the stormiest August periods in decades. Meteorologists noted that the unusual strength of both storms was linked to a highly active jet stream, itself influenced by complex global weather patterns.

Aftermath and Legacy

After Francis moved through, a spell of calmer weather returned, but the storm left its mark. It remains one of the few named storms to strike the UK during August since the introduction of the storm-naming system in 2015.

For weather watchers, it’s remembered as a curious anomaly, a taste of autumn delivered at the height of summer.