11/21/2022, 4:52 am EST

Europe Month 1-3 Outlook: Marginally mild forecast for winter in Europe. However, the forecast trend is colder especially if snowy.

Executive Summary: There are a lot of red flags for the Europe winter 2022-23 forecast. Pieces of the persistent NAWH upper trough are ejected eastward across Europe frequently during December and January. Each month is stormy for Southeast/East Europe (and Ukraine). The concern is the upper trough could generate a deep snow cover and bias the forecast colder than indicated. By February, widespread snow cover is present and could bias an already chilly forecast colder. The CIC-CA forecast indicates marginally mild temperatures (due to the warm SSTA surrounding Europe during winter) for Southeast Europe and is normally cold elsewhere. The forecast trend is colder and stormy. If the precipitation is mostly snow, a colder result is likely. Fig. 1-2: The Climate Impact Company temperature and precipitation anomaly forecast for DEC/JAN/FEB 2022-23 across Europe. Climate: As the last third of November arrives, there are significant winter signals appearing across Eurasia. Most important is the expansive snow cover well ahead of schedule across Asia and recently evolving over Eastern Europe (Fig. 3). The North Atlantic warm hole (NAWH) is vividly depicted in North Atlantic SSTA analysis although waters surrounding Europe remain warmer than normal (Fig. 4). The combination of expanding snow cover to the east of Europe and the NAWH upper trough implies the climate pattern heading into meteorological winter will produce a conflict between warm influence from the west and cold weather risk from the east. The ECMWF global SSTA forecast for mid-winter yields a warm North Atlantic including waters surrounding Europe with the NAWH well-established south of Greenland. La Nina is not quite as strong across the eastern equatorial Pacific Ocean (Fig. 5). The SSTA forecast yields support to above normal 500 MB heights across Europe for the winter season which correlates to a mild climate. However, arctic air is low-level in character and can emerge despite above normal 500 MB heights. Fig. 3-5: Northern hemisphere snow cover, North Atlantic warm hole, and global SSTA forecast by ECMWF for January 2023. December 2022: A piece of the NAWH semi-permanent trough shifts eastward to Europe on a regular basis during early meteorological winter. Consequently, the forecast is confident producing a stormy pattern across South and Southeast Europe and most likely Ukraine. Only Southwest Europe is drier than normal during December. The temperature forecast is not as confident. There is gathering arctic air over Central Asia during late November. The CIC-CA forecast has difficulty knowing how far west that air mass could travel. If the cold pattern to the east extends westward, most of the precipitation in Southeast Europe is snow and invites a much colder solution. Additionally, the upper trough parks over Central Europe, which could also trigger a colder forecast is snow cover is present. The CIC-CA forecast emphasizes a warm bias due to the much warmer than normal surrounding waters around Europe. The forecast is certainly trending less warm and the stormy weather shifts from Western Europe in the previous outlook to Southeast Europe. Bottom line? Trending more stormy, less mild and could be colder. Fig. 6-7: The preliminary Climate Impact Company temperature and precipitation anomaly forecast for December 2022 across Europe.  January 2023: The CIC-CA forecast is marginally mild across Eastern Europe through Ukraine and normally cold elsewhere. There is not much change from the previous forecast. Once again, part of the NAWH upper trough is emitted eastward and becomes semi-permanent over Eastern Europe. The upper trough should produce a large swath of above normal snowfall across Central and East Europe to the Black Sea region. Once again, the CIC-CA forecast is warm-biased due to warm SSTA surrounding Europe especially across the Mediterranean Sea. The forecast could easily be colder and would certainly not be warmer. Fig. 8-9: The Climate Impact Company temperature and precipitation anomaly forecast for January 2023 across Europe.  February 2023: Similar to the U.S. winter forecast, February is the coldest month (relative to normal) across Europe. The colder look is produced by above normal snow cover. The forecast trend is colder. The upper air pattern supports a less stormy month except in Southeast Europe where heavy snow could occur. Once again, due to widespread snow cover, the outlook could be colder than indicated. Fig. 10-11: The Climate Impact Company temperature and precipitation anomaly forecast for February 2023 across Europe.