earth science

Weather forecasting for Operation Overlord

Weather forecasting for Operation Overlord is a earth science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Weather forecasting for Operation Overlord rather than just read about it. In short: The Overlord planners for the invasion of Europe in 1944 specified suitable weather (wind, cloud, tidal and moon conditions) for the assault landing; with only a few days in each month suitable. In May and June 1944 frequent pre-assault meetings were held at Southwick House in Hampshire near Portsmouth by Eisenhower with Group Captain James Stagg of the RAF, the chief meteorological officer, SHAEF, his deputy Colone…

Key takeaways

Weather forecasting for Operation Overlord belongs to earth science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Weather forecasting for Operation Overlord to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Weather forecasting for Operation Overlord from memory before moving on to harder problems.

Reference excerpt

The Overlord planners for the invasion of Europe in 1944 specified suitable weather (wind, cloud, tidal and moon conditions) for the assault landing; with only a few days in each month suitable. In May and June 1944 frequent pre-assault meetings were held at Southwick House in Hampshire near Portsmouth by Eisenhower with Group Captain James Stagg of the RAF, the chief meteorological officer, SHAEF, his deputy Colonel Donald Yates of the USAAF, and his three two-man teams of meteorologists. Stagg was described as a "dour but canny Scot." He had been given the rank of group captain in the RAF "to lend him the necessary authority in a military milieu unused to outsiders". The senior commanders were General Bernard Montgomery, Admiral Sir Bertram Ramsay and Air Marshal Sir Trafford Leigh-Mallory, plus Eisenhower's deputy, Air Marshall Arthur Tedder, his chief of staff Walter Bedell Smith and his deputy chief of staff, Major General Harold R. Bull.

Stagg reported the team consensus, although this has been glossed over in popular memory. Admiral Sir George Creasy remarked on 4 June: "Here comes six feet two inches of Stagg and six foot one inch of gloom...". British general Frederick Morgan (head of COSSAC) had half-jokingly said to him "Remember, if you don't read the runes (or signs) right, we'll string you up from the nearest lamppost".

Forecasting teams The three weather forecasting teams at Southwick House were from the UK Met Office at Dunstable, the USAAF Eighth Air Force at High Wycombe, and the Royal Navy at Portsmouth; they usually met twice daily; at 9:30 am (0930 hours) and 4:00 pm (1600 hours), with Eisenhower and his senior commanders.

The Royal Navy team was Commander Geoffrey Wolfe and New Zealander Lieutenant Commander Lawrence Hogben. Hogben recalled that "We six never agreed on anything except that Stagg was not a good meteorologist and that he was a bit of a glory hound". At heart a geophysicist, Stagg was appointed as SHAEF weatherman for his administrative skills to co-ordinate Army and RAF forecasting; he had only two years experience of forecasting in the Iraqi desert. The civilian Met Office team was Charles K. M. Douglas and Norwegian Sverre Petterssen of the Norwegian Air Force. Douglas had told USAAF commanders Spaatz and Doolittle in 1942 that "a forecast for more than a day or two ahead in this country can be nothing more than speculation". The USAAF team was Irving P. Krick and Ben Holtzman. Hogben thought their forecasts for daylight bombing runs over Germany made by looking at forty years of weather maps were "pure bunk" and the Norwegian Petterssen thought that Krick was "talking nonsense" in claiming reliable forecasts for up to five days. Pre-war they had forecasted for Hollywood film studios (e.g. for the "burning of Atlanta" scene in Gone with the Wind). Krick (a physics graduate and college professor) was regarded by his rivals as "brash" and "a salesman to his fingertips". Donald Yates was a former student of Krick. The American team was based at the USAAF facility Widewing used for SHAEF HQ at Camp Griffiss in Bushy Park near Teddington.

Tidal predictions A full moon was desirable, as it would provide illumination for aircraft pilots and have the highest tides. Having the landings shortly before dawn, midway between low and high tide, with the tide coming in would improve the visibility of obstacles the enemy had placed on the beach while minimising the amount of time the men had to spend exposed in the open. Specific criteria were set for wind speed, visibility, and cloud cover. The previous night had to be reasonably light (moonlight) for darkened convoys; although airborne troops needed a full or nearly full moon but late-rising so with darkness until they were dropped. The invasion zone tidal range was about 23 ft (7m) and the landings should be on a rising tide to allow landing craft to run aground, unload and then withdraw without becoming stranded. Landings had to be at about the same time on all beaches to avoid later arrivals meeting an alerted enemy, and Omaha had an exposed tidal flat of 300 yards (275m) to cross. It was decided that the assault should be one hour after low tide and within one hour of first light. Arthur Doodson head of the Liverpool Tidal Institute advised the Royal Navy on European coastal areas, and was asked in October 1943 by Commander Ian Farquharson to make tidal predictions for Normandy, which was disguised as "Position Z". He created two tide-prediction machines. The required light and tidal conditions occurred for only six days a month, and when strong moonlight for airborne operations was added there were only three days per month.

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with Weather forecasting for Operation Overlord

Start with the simplest possible case. Write down what Weather forecasting for Operation Overlord claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In earth science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Weather forecasting for Operation Overlord before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Weather forecasting for Operation Overlord ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Weather forecasting for Operation Overlord

In research: Weather forecasting for Operation Overlord appears in earth science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Weather forecasting for Operation Overlord in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Weather forecasting for Operation Overlord is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1944 in England, 1944 in France, 1944 in military history, so understanding it makes those chapters shorter.
In everyday life: Look for Weather forecasting for Operation Overlord outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Weather forecasting for Operation Overlord” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Weather forecasting for Operation Overlord in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Weather forecasting for Operation Overlord means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Weather forecasting for Operation Overlord out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Weather forecasting for Operation Overlord in simple terms?

Why does Weather forecasting for Operation Overlord matter?

Because it connects several earth science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Weather forecasting for Operation Overlord?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Weather forecasting for Operation Overlord.