1

Scott A. Yuknis High impact weather forecasts, climate

assessment and prediction. 14 Boatwright’s Loop Plymouth, MA 02360

Phone/Fax 508.927.4610 Cell: 508.813.3499

ClimateImpact@comcast.net

Climate Impact Co. Season 1-3 Ahead Outlook for Europe/Western Russia

Issued: Wednesday, February 14, 2018

Highlight: A wet spring followed by a hot summertime.

Executive Summary: The Climate Impact Company climate outlooks for spring, summer and autumn 2018 for Europe are issued. The forecast is based primarily on the effect on Europe/Western Russia climate caused by a warmer-than-normal North Atlantic. The spring outlook is quite wet from South-Central Europe to Romania/Ukraine. However, summertime brings widespread anomalous warmth with most dryness in South-Central Europe eastward to the Black Sea region.

Climate discussion: The European climate has been dominated by a semi-permanent trough over northwest Europe during the past 6+months (Fig. 1-2). The feature remains semi-permanent and is linked to the large area of warm SSTA in the north-central North Atlantic (Fig. 3) where an equally strong high pressure ridge has persisted. The warm SSTA pattern emerged last year and became part of one of the strongest warm North Atlantic patterns on record as defined by the Atlantic multi-decadal oscillation (AMO). Forecast models maintain the warm North Atlantic well into 2018 with strengthening likely (Fig. 4). The warm SSTA pattern across the North Atlantic is a dominant force on the atmosphere and attendant climate pattern for Europe to Western Russia for 2018. The climate outlooks are linked to analog years producing strong warm phase AMO index signatures (Fig. 5). The influence of the long-standing +AMO and attendant upper air pattern can be realized sensibly by taking a look at anomalous soil moisture. As of February 1, the soil moisture regime was wet across Central Europe to Northwest Russia (Fig. 6) due to the persistent upper trough. This wet soil regions implies lack of anomalous warmth for several months ahead. The only dryness in in Southwest Europe and Northeast Europe and south of the Black Sea region.

2

Fig. 1-2: 500 MB anomalies for the past 30 days and past 180 days identify the strong trough presence across northwest Europe.

Fig. 3: The North Atlantic upper ridge is linked to very warm N. Atlantic SSTA.

3

Fig. 4: The NMME global SSTA forecast for JUN/JUL/AUG 2018 indicates a robust warm North Atlantic pattern certainly significant to Europe climate.

Fig. 5: The Climate Impact Company AMO analog forecast for 2018. The warmest analogs (2017 and 2006) are used to project the base climate

patterns for Europe/Western Russia.

4

Fig. 6: The soil moisture regime as of Feb. 1 across Europe/Western Russia identifies the long-term influence of the upper air pattern producing a wet

regime over Central Europe/Northwest Russia with limited dryness. Climate outlooks: The Climate Impact Company climate outlooks for Europe are preliminarily based on analog years with strong +AMO presence from the climate cycle of the past 20 years. The analog years are 2017 and 2006. The analog years are taken from the climate cycle when ENSO/PDO and AMO flipped their long-term (cycle) phase in the mid-to-late 1990’s.

MAR/APR/MAY 2018: During meteorological spring 2018 the same upper air pattern affecting Europe since last year remains in-place: Persistent Northwest Europe trough. Consequently, cooler-than-normal temperatures are likely over Northwest Russia plus North and Northeast Europe. Anomalous warmth begins to emerge across Southern Europe. In-between the persistent thermal regimes the storm track is active. Above normal precipitation is expected from South-Central Europe to Eastern Europe with excessive precipitation forecast across Romania. Parts of Ukraine and Western Russia are also wetter than normal. Drier than normal conditions affect Spain and Portugal plus Italy to far Southeast Europe. Wet soils across central and eastern Europe to Western Russia likely remain into the summer season while dryness evolves in Southern Europe.

5

Fig. 7-8: The Climate Impact Company MAR/APR/MAY 2018 temperature and precipitation anomaly forecast for Europe.

JUN/JUL/AUG 2018: Emerging high pressure across Europe is forecast during meteorological summer 2018 with a secondary (and stronger) high pressure zone over the Black Sea region. The result is a widespread warmer than normal climate across Europe and Western Russia for summertime. The

6

strongest anomalies are across Ukraine to eastern Turkey. Occasionally a showery regime can affect Germany to the southern Baltic nations due to an upper trough extending southwestward from a semi-permanent location in Northwest Russia. Dryness is most profound over Italy and Ukraine plus northern Europe.

Fig. 9-10: The Climate Impact Company JUN/JUL/AUG 2018 temperature and precipitation anomaly forecast for Europe.

7

SEP/OCT/NOV 2018: Meteorological autumn is warmer-than-normal across most of Europe. The upper air forecast calls for a large high pressure ridge to reside over Southwest Europe causing the strongest anomalous warmth across Central Europe and keeping most of Southern Europe drier than normal. A wet regime evolves in the Baltic region westward to U.K.

Fig. 11-12: The Climate Impact Company SEP/OCT/NOV 2018 temperature and precipitation anomaly forecast for Europe.