Mud Season In Ukraine

The ongoing tragedy in Ukraine has a number of meteorological dimensions, some of which will be touched upon in this blog.

To begin, the war has essentially cut off surface meteorological observations over the region.  Below is the plot from a few hours ago.  Great density of weather observations over Europe....and even some over Russia....but virtually no weather data coming out of Ukraine.   Western Russian was pretty chilly...temperatures only in the teens (F).  


We are now coming into mud season over Ukraine and vicinity, mud that has the bain of intended conquerors for centuries.   As shown in the climatological temperatures for Kyiv shown below, March is a time of very rapid warming, which results in the rapid melting of snow.

                                                                   Graph courtesy of WeatherSpark

And  in late spring precipitation begins to increase as well (see climatological rainfall below)'


With warming temperatures, melting snow, and then increasing rain, Ukraine experiences an infamous muddy season during spring called  Rasputitsa (with another muddy period in autumn).  Heavy clay soils that inhibit drainage adds to the muddy woes of the region.

March-April 1942

Increasingly muddy conditions are a problem for invaders, working against travel in the many areas of Ukraine without paved roads.

The weather had been relatively warm and dry over Ukraine recently, and the latest high-resolution satellite imagery does not show much snow cover over the western 3/4 of the nation.


The latest numerical weather forecasts show very cold air over Russia that will continue to spread over eastern Ukraine for the next few days.

Surface air temperatures (°C) for 7 PM PDT on Wednesday.  Light green is the coldest temperature.

But warming is ahead (see weather.com forecast for Kyiv), which should be a relief to the embattled population of the region.    Unfortunately, that warmth will come with relatively sunny skies, which would be favorable for aircraft operations.




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