Fig. 1: Northern hemisphere 15-day temperature anomalies. Announcement: Climate Impact Company (CIC) forecasts are powered by Commodity Weather Group (CWG) Storm Vista Weather Models (SVWM). Some of the CWG model products were suggested by CIC, particularly oceanic/SSTA depictions. Previously, AI forecast models were available only on the ECMWF web site. There are restrictions on usage therefore only limited presentation availability. Now, CWG offers the AI Forecast Net Version2 (model) projections considerably adding ability to provide AI forecasts to all clients. Additional products are on the way! Now, as for winter weather in the northern hemisphere, stratospheric warming caused arctic air to develop and evolve across Eurasia this weekend. The AI 15-day northern hemisphere temperature anomaly forecast indicates the cold air will release southward throughout Asia over the next 2 weeks (Fig. 1). There is limited cross-polar cold airflow into Canada and the U.S. and Europe are on the warm side of this event. The most recent diagnostics on El Nino were made available earlier today. Clearly, oceanic El Nino is weakening although certainly maintaining moderate strength. The atmospheric El Nino peaked in February due to the strongest 18-day surge of negative southern oscillation index (SOI) of the 2023-24 warm ENSO episode (Fig. 2). Implied is El Nino climate will linger 1-2 months beyond dissipation of oceanic El Nino during later Q2/2024. Fig. 2: The 4 strongest periods of El Nino climate, identified by negative southern oscillation index, of the 2023-24 El Nino episode. The cold air episode avoids Europe. Instead, a steady fetch of North Atlantic moisture causes several storms during the next 2 weeks across Europe causing excessive rainfall for many areas (Fig. 3) while the climate is generally mild. In the U.S., with MJO influence weakening, the 15-day precipitation outlook is reminiscent of what spring 2024 may produce…a drier climate across the Southern U.S. while California and the Upper Midwest are wet (Fig. 4). Fig. 3-4: Europe and North America 15-day percent of normal precipitation forecasts. Heavy rains extend across East Brazil this week while Northern Argentina is dry (Fig. 5). In the 6-10-day period, the pattern flips drier in Brazil while Northern Argentina is wetter (Fig. 6) in a changeable weather pattern which is unusual for late summer. Models vary on whether an active ITCZ can extend northward into the Ivory Coast drought area. ECMWF is farthest south with heavy rain (Fig. 7). In Australia, the 15-day forecast (using AI) is hot especially across the Western Australia drought zone (Fig. 8). Fig. 5-6: ECM ENS 1-5-day and 6-10-day precipitation anomaly forecasts across South America. Fig. 7-8: ECM 10-day forecast of tropical Africa rainfall and AI 15-day temperature anomaly forecast across Australia.