When did Soviet roads dry in 1941?

[Rich Rostrom]

It has been pointed out several times that
Operation BARBAROSSA was not much delayed
by the Balkan campaign, but went off when
the mostly dirt roads in the USSR had dried
enough to be usable.

What is the earliest date that Soviet roads
were dry enough?

Could BARBAROSSA have kicked off (without
bogging down in mud) a month earlier? Two
weeks earlier?

[WJHopwood]

On Wednesday, July 6, 2016 at 9:59:09 AM

Post by Rich Rostrom
It has been pointed out several times that
Operation BARBAROSSA was not much
delayed by the Balkan campaign, but went
off when the mostly dirt roads in the USSR
had dried enough to be usable. What is the
earliest date that Soviet roads were dry
enough?

Hitler's Directive No.21 pertaining to the Soviet
campaign was issued on December 18, 1940.
It outlined the objectives of the campaign and
set the starting date for Barbarossa to be May 15,
1941. Certainly with five months to go over the
planning of details the German military must
have concluded that by May 15 Soviet roads
they intended to use would be passable by
that time.
As it turned out Barbarossa was delayed
by the Balkan campaign for as long as five weeks
and did not start until June 22, 1941. By then the
problem with Soviet roads encountered by the
German advance was not that they were too wet
but that they were too dry. Moving traffic turned
up clouds of dust whic got into everything that
moved causing more mechanical problems to
German equipment than had been anticipated.

WJH

[William Clodius]

<snip>
Hitler's Directive No.21 pertaining to the Soviet
campaign was issued on December 18, 1940.
It outlined the objectives of the campaign and
set the starting date for Barbarossa to be May 15,
1941. Certainly with five months to go over the
planning of details the German military must
have concluded that by May 15 Soviet roads
they intended to use would be passable by
that time.

No. The May 15th date was tentative, based on typical weather. The road
would usualy, but not always, be passable by that time. That particular
year at least some of importance would only be passable by early June.
While the June 22 start date for Barbarosa was chosen well in advance of
knowledge of the weather in mid-May, and determined largely by the
effects of the Balkans campaign, if they hadn't launched the Balkans
campaign they likely would have gained only a couple of weeks of
additional time for the campaign.
<http://www.history.army.mil/books/wwii/balkan/20_260_5.htm>

[Rich Rostrom]

Hitler's Directive No.21 ...set the starting date
for Barbarossa to be May 15, 1941. ... Barbarossa
did not start until June 22, 1941. By then the
... Soviet roads ... were too dry.

Interesting and useful information.
Thanks for the response.

[Geoffrey Sinclair]

Post by Rich Rostrom
It has been pointed out several times that
Operation BARBAROSSA was not much delayed
by the Balkan campaign, but went off when
the mostly dirt roads in the USSR had dried
enough to be usable.
What is the earliest date that Soviet roads
were dry enough?
Could BARBAROSSA have kicked off (without
bogging down in mud) a month earlier? Two
weeks earlier?

First consider the length of the front and the way it ran North
South and the closer to the poles the cooler the weather and
the longer the snow lingers and the later it melts as the
general rule. Add the melt tends to make the rivers run high.

The initial front, ignoring Romania was around 500 miles /
800 km. Add Romania, which attacked about a week
later and Hungary and the front is up to 1,400 km, or 750
miles / 1,200 km if you simply measure north to south.

There is no one day, it is quite clear the terrain in the south
was passable before that in the north (on average).

The original planning date for the invasion was 15 May, the
invasion of the Balkans shifted the planned date 4 weeks to
mid June. So that is one for the Balkans were the delay.

The reports are the Bug river, forming part of the German
USSR border was over its banks until early June. Heavy
rain kept falling in the north during early June. The weather
is the main reason the date was set for the 22nd and means
the invasion was unlikely to have occurred much earlier even
without the Balkans fighting.

Then comes the time it takes to allow for 3 army groups and
associated naval and air power to co-ordinate their attacks,
Hitler set the 22 June date on the 17th.

There are people claiming the reports of bad weather in
May and June are exaggerated, the point would be to find
the relevant records. The other thing to note is how far
away you need to be to avoid a flood event, it is usually
less than the length of the northern part of the front. Records
of river heights would be a good guide.

After the invasion there are a number of accounts where local
rainfall made movement, including by road, very hard.

All accounts say the attack could not have happened a month
earlier without significant mobility problems. It seems like a
fortnight earlier would have been a problem in the north,
a week earlier would more depend on local weather over
that week. If you look at Lithuania's weather records you find
monthly precipitation rising from 30.1mm in February to around
77mm in June and July, and the May to September period sees
about 40% of annual precipitation.

Essentially little change unless the claims the German Generals
are telling lies about the weather can be substantiated, and the
first hurdle is why would they?

Geoffrey Sinclair
Remove the nb for email.

[IndSyd]

On Thursday, July 7, 2016 at 11:43:39 AM UTC-4, Geoffrey Sinclair wrote:

1st The choice could have been made to attack first on the Southern
front only using some of the assigned forces plus the Balkan forces.
But the Balkan forces need refit, rest, maintenance etc. so May 15
even in the South would be impractical.

2nd Cloud cover height is a critical item for Luftwaffe army support
operations. I think anything less than 300m or 1000ft cloud bases would
hamper mass operations. With May rains the ceilings would be low.

[Rich Rostrom]

Post by IndSyd
Cloud cover height is a critical item for Luftwaffe army support
operations. I think anything less than 300m or 1000ft cloud bases would
hamper mass operations. With May rains the ceilings would be low.

Important fact!

Thanks!

[William Clodius]

<snip>
1st The choice could have been made to attack first on the Southern
front only using some of the assigned forces plus the Balkan forces.
But the Balkan forces need refit, rest, maintenance etc. so May 15
even in the South would be impractical.
<snip>

Also, of course, launching an attack on a third of a front (unless they
can get the Romanians to commit early) would allow the Soviets, to
prepare their defenses on the rest of the front, reinforce the immediate
point of attack, call up their reserves before the main attack, begin a
more extensive draft, and ramp up their production.




Padding to avoid complaints

[Rich Rostrom]

... consider the length of the front... up to 1,400 km...
There is no one day, it is quite clear the terrain in the south
was passable before that in the north (on average).

Well, I suppose that's obvious (though I hadn't
considered it). But then... was it necessary to
wait till the entire front was clear?

...the Bug... was over its banks until early June. Heavy
rain kept falling in the north during early June. The weather
is the main reason the date was set for the 22nd and means
the invasion was unlikely to have occurred much earlier even
without the Balkans fighting.

Very valuable information - thanks.

After the invasion there are a number of accounts where local
rainfall made movement, including by road, very hard.

Hmm. Yet according to Mr. Hopwood, there were also
problems with vehicles disabled by the thick dust
kicked up from very dry roads. On a 1,400 km front,
such various conditions would be inevitable, I guess.

All accounts say the attack could not have happened a month
earlier without significant mobility problems.

Thanks.

It seems like a fortnight earlier would have been a
problem in the north, a week earlier would more
depend on local weather over that week.

And thanks.

If you look at Lithuania's weather records you find
monthly precipitation rising from 30.1mm in February to around
77mm in June and July, and the May to September period sees
about 40% of annual precipitation.

Wow. Thanks.

[Geoffrey Sinclair]

Post by Rich Rostrom

... consider the length of the front... up to 1,400 km...
There is no one day, it is quite clear the terrain in the south
was passable before that in the north (on average).

Well, I suppose that's obvious (though I hadn't
considered it). But then... was it necessary to
wait till the entire front was clear?

So where is the evidence they waited until the entire front
was clear? Is it an assumption?

Given the distances involved the possibility of having the
correct weather everywhere are remote. That is passable
terrain, minimal weather effects on air and ground operations.

As I understand it for at least some parts of the western world
in the 1970's stating tomorrow will be basically like today was
about as accurate as the official weather forecast, that today's
7 day forecasts are about as accurate as the 1990's 3 day ones.

How accurate were the peacetime 1930's forecasts, and how
much did the war degrade them? Consider the usual variations
for example in June 1941 Oxford's hottest day exceeded 90
degrees F, coldest was around 51 degrees F.

Remembering Hitler gave the go ahead about 5 days before
the attack.

Where exactly is the ability to give accurate forecasts across
the front to ensure the "entire front was clear"?

It seems the basic rule is in the north of the front, the direct
route to Moscow, mid May is about right on average for the
start of the passable terrain season, the longer you wait
after into June that the overall better the initial going will be.
That is as much as the Germans had to go on.

In 1941 at least some of the northern rivers were running high
in early June along with heavy rain in some places.

http://www.seaclimate.com/e/e4.html
"The year 1941 it was throughout too cold and dull with high
precipitation for the whole Reich (Witterungsbericht, 1948)[3].
Actually, this applied more to the southern part of Germany,
with 130 to 160% more rain northwest of the river Danube
(Donau), the middle part of the river Elbe and Silesia. At
the same time all coastal areas had good weather with
above average parameters: 85 to 95% of precipitation,
less cloud cover (2-5%), less dull days (2-10 days), and up
to 200 hours more sunshine"

Remembering time zones are roughly 15 degrees and 1 hour,
which means the people in the east of the zone see things like
sun rises an hour ahead of the people in the west of the zone.

Using London as the point of measurement.

Now add the phase of the moon, the 25th of August 1939 was
around 4 days before the full moon, but it set around 0:40
hours, by the 1st of September it was setting at around 07:25
after rising around 19:00 the previous evening, and it was 2
days past full.

9 April 1940, 2 days past full moon but rising at 6:30 am, so
after dawn, setting around 21:40, so after dark.

10 May 1940, 3 days after a new moon, again rising after dawn
and setting after dusk, around 22:30.

6 April 1941, 1 day after the first quarter, rising about 2:30, setting
about noon.

15 May 1941 the original Barbarossa plan date, 4 days past the
full moon, rising at 8:30, setting about midnight.

22 June 1941, 2 days before a new moon, rising about 2:30,
setting around 18:00.

So overall we can conclude the Germans were not greatly worried
about the state of the moon.

By the way, be aware the moon replicates the sun's apparent
motion. For example 3 May 1941, about 9.5 hours rise to set,
by the 13th it was about 16 hours.

At Odessa on the Black Sea on 21 June this year sunrise about
5:04, set 20:54, there is about 2.5 hours of night, that is outside
of Astronomical then Nautical then Civil Twilight, then day. At
Kaunas in Lithuania, sunrise 4:46, sunset 22:07 the sky never
becomes darker than nautical twilight. So not much effect on a
pre dawn attack.

Post by Rich Rostrom

After the invasion there are a number of accounts where local
rainfall made movement, including by road, very hard.

Hmm. Yet according to Mr. Hopwood, there were also
problems with vehicles disabled by the thick dust
kicked up from very dry roads. On a 1,400 km front,
such various conditions would be inevitable, I guess.

Exactly but tending to dusty as summer progressed, so mud
tended to be a transient thing, the reverse later in the year.

Ever noticed the connection between forests and higher rainfall,
and grasslands and lower rainfall? The more forested north
versus the steppe in the south?

Geoffrey Sinclair
Remove the nb for email.