John Bull

May 20, 2018

27 min read

The Forecaster: The Man Who Decided D-Day

In 1944 Eisenhower gave Group Captain James Stagg a near-impossible task: Predict the weather for D-Day.

Planes on their way to the Normandy beaches

May 15 1944, Hammersmith, London (D-Day -21)

May 28 1944, SHAEF Advanced Headquarters, Portsmouth (D-Day -8)

Group Captain James Stagg
Lieutenant-Colonel Donald Yates

May 28 1944, Senior Commander’s Briefing, Portsmouth (D-Day -8)

May 29 1944, the Weather Hut, Portsmouth (D-Day -7)

The problem of predicting the weather

Irving Krick
Sverre Petterssen

“Possible or not possible?”

Same day. Task Force 24, Coast of Greenland (D-Day -7)

May 31 1944, the Weather Hut, Portsmouth (D-Day -5)

June 2 1944, Blacksod Point, Republic of Ireland (D-Day -3)

Blacksod Point. Photo by Evita-Coyle.

Later that day, the Weather Hut, Portsmouth (D-Day -3)

Same day, Senior Commander’s Briefing, Portsmouth (D-Day -3)

That Evening, the Weather Hut, Portsmouth (D-Day -3)

June 3 1944, HMS Hoste, West Coast Of Ireland (D-Day -2)

That same morning, Blacksod Point, Republic of Ireland (D-Day -2)

That Evening, the Weather Hut, Portsmouth (D-Day -2)

The Moment of Truth

21:30 June 3 1944, Senior Commander’s Briefing, Portsmouth (D-Day -2)

04:15 June 4 1944, Senior Commander’s Go Briefing, Portsmouth (D-Day -1)

13:00 June 4 1944, Blacksod Point, Republic of Ireland (D-Day -2 [REVISED])

20:30 June 4th 1944, Convoy U-2A, The Channel (D-Day -2 [REVISED])

21:30 June 4th 1944, Senior Commander’s Briefing, Portsmouth (D-Day -2 [REVISED])

June 6th 1944. D-Day.

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