#NAFOWeather 🧵 1/ Weather week in review (23-29 May 2023): Widespread thunderstorms provided significant rain near the Line of Conflict (LoC), with a range of 15-90 mm in the south and 30-100 mm in the east and north.
2/ Rainfall from thunderstorms was not uniform with some locations close to the LoC receiving weekly peak total rainfall 80-105 mm including Oleshky, Vuhledar, Bakhmut and Raihorodka.
3/ Daily peak rainfall totals from thunderstorms max'ed out at 30-60 mm per day causing local flooding as reported by social media validating satellite precipitation accumulation analysis.
4/ Impact on soil moisture and trafficability from 7 days of rainfall has been substantial with daily soil moisture analysis (updated through May 27th) returning to peak soil moisture levels observed back on May 1st.
5/ Unfortunately, thunderstorms and rain showers are predicted to continue through 31 May 2023 likely providing additional rainfall of 5-35 mm in the south and 25-45mm in the east and north.
6/ Predicted impact from recent and predicted rainfall upon trafficability is "no go" conditions for the LoC through this week with drying conditions helping to dry soil after 3 JUN. Next week, conditions will likely improve faster in the south than in the east and north.
7/ Week 3-4 C3S long range forecast (15-22 June 2023) has south and east Ukraine with higher chance of rain than normal. Additional significant rain in early and mid June will necessarily keep trafficability degraded. /end
2/ Loop of several cloud-free Sentinel-2 passes of #KakhovkaHPP this month, latest 29 May 2023, show white turbulent flow downstream of sluice gates.
3/ @lhinnant published an article "Damage to Russian-occupied dam submerges Ukrainian reservoir island community" 25 May 2023 for @AP. Worth a read. apnews.com/article/ukrain…
1. Soil Moisture Update: 15 May 2023, a #NAFOWeather🧵
I'm "officially" declaring #MudSeason over based on limited rainfall since May 1st & marginal rain forecast in the next 2 weeks. Soil is dry enough to support most vehicles across most of the LoC.
2. Recent Rainfall (past 2 weeks): Donetsk and Luhansk received about 5-15 mm rain of on May 8-9, otherwise, a dry 2 weeks.
3. Soil Moisture Change (past 2 weeks): There has been a general soil drying trend from 30 April to 14 May with least moisture in the south and greatest soil moisture in Donetsk.
Time-series loop from 27 March 2023 to 6 May 2023. Note the "brightening" downstream (left side) of the #KakhovkaHPP sluice gates last frame in loop which is water flowing over the top of the dam. Over-topping is particularly evident on the 3 northern most sluice gates. /2
Why is this happening? Recall the Russian occupiers blew up the road and rail deck above the #KakhovkaHPP dam sluice gates on 10 NOV 2022 as part of the RF retreat ("strategic repositioning") from the Dnipro right bank. /3
1. Ruschist operation of Kakhovka HPP (K-HPP) dam has been reckless. Kakhovka Reservoir (KR) water level has alternated from record low to record high in just 3 months. Loop (6 FEB-6 MAY 2023) shows sand bars receding with rising KR water. #NAFOWeather🧵
2. These images are of the K-HPP from Left: 6 FEB, and Right: 6 MAY 2023 (enhanced from data included in loop).
3. North Crimean Canal intake, Left 20 FEB 2023 Right 6 May 2023: Latest image show water gushing through NCC intake gate at Tavrisk as record KR level is pushing water through gravity fed NCC at high rates.
1. Russians are once again attempting to frighten residents in occupied Kherson and Zaporizhzhia on the left bank of Kakhovka Reservoir into evacuating. This is part of a larger information operation ahead of the Ukrainian offensive. A #NAFOWeather 🧵
2. TASS reported (some western media repeated) that the Kakhovka HPP dam could burst and this would flood Zaporizhzhia NPP and surrounding communities. This is pure rubbish. If the Kakhovka HPP dam burst, Kakhovka Reservoir would dramatically LOWER as these location are upstream.
3. Russian propaganda uses facts, often reported by the west, with other false statements to create an environment of fear and uncertainty. It is TRUE Kakhovka Reservoir is at record high levels and the K-HPP controls water discharge for K reservoir.