U.S. Corn Belt Needs Mexican Monsoon Help for Wet Pattern Change The 2019 super heat (stress) wave ends due to heavy to severe thunderstorms along a cold front suppressing the hot pattern the next day or two. Temperatures were hot with this episode, no doubt about that! But historically, the heat was not record-breaking. HOWEVER, the heat was made historically intense by the added factor of high humidity spawned by a wet spring in the Midwest/Mid-South U.S. and that air mass extended eastward to the East Coast in recent days. The wet weather along the cold front will ease what has been a dry mid-summer for the east/south Corn Belt. But dryness is likely to return to finish July as the most favored 6-10 day forecast by mega-clusters is drier than normal (Fig. 1). Climate models are suggesting August is wet in the Central U.S. For that idea to work the Mexico (wet) Monsoon needs to ignite as suggested in the 11-15 day period (Fig. 2). Fig. 1-2: Mega-clusters most likely U.S. rainfall pattern for days 6-10/11-15. August Precipitation Climate Forecasts for the U.S. Fig. 3-4: August precipitation forecasts. Another Europe Heatwave But it won’t last Another surge of heat returns to Europe this week (Fig. 5) with strongest hot temperature anomalies centered on France. 100+ appears early week in Spain extending to France WED/THU. The hottest day featuring 105 risk in France is Thursday. After Thursday models vary on whether the heat breaks down. The ECMWF lingers the heat but GFS vigorously ceases heat risk. Favored is persistence which returns cooler temperatures especially (cooler) in Western Russia (Fig. 6). Fig. 5-6: Mega-clusters temperature anomaly forecast for days 1-5 identify hot weather trending cooler by days 11-15. Dry Soil/Drought Regions in Europe Not Profound but are Increasing The first third of July drought analysis by the European Drought Observatory (Fig. 7) indicated worsening dry conditions for crop areas in northeast France and northern Germany plus parts of Poland and also eastern Ukraine. This week’s heat wave is likely to accelerate drought risk for parts of west and central sections of Europe. Fig. 7: The European Drought Observatory highlights drought risk areas valid the first third of July 2019. Favoring Wet Weather Black Sea/Western Russia The GFS OP is a changeable model BUT is most likely correct maintaining more rain than dryness across the Black Sea region and Western Russia most of the remainder of July and into early August (Fig. 8). Showery weather this week is propelled by a persistent upper trough in Western Russia and a second in the Black Sea region. The trough strengthens and could become quite impressive in the medium/extended-range as more cool weather returns (accompanied by wet weather). Fig. 8: The GFS OP is generally wet across the Black Sea region and Western Russia the next 15 days. Prohibitive Rainfall Northern Argentina to Southeast Brazil Next 15 days Forecast models agree that the next 15 days across most of Brazil and Argentina are dry. However, a wet stretch from Paraguay to Uruguay and into far Southeast Brazil is wet and a lot of rain is possible. The 15-day rainfall forecast by both the GFS and ECM ensembles indicates 4-8 in. of rain in this zone most on or just north of the Uruguay northern border.