Strong Winds, Heavy Rainfall, and Severe Convection Expected in Central Canada and Central and Eastern United States

It is forecasted that from June 1 to 7, under the combined influence of an upper-level trough and a low vortex (Figure 1), central and southeastern Canada, as well as the central and eastern United States, will experience significant stormy weather moving from west to east. In these regions, widespread moderate to heavy rain is expected. Specifically, parts of eastern Northwest Territories in Canada, southern Kansas, most of Oklahoma, northern Texas, southern Missouri, and central Illinois in the United States will see heavy downpours, with localized areas experiencing intense rainstorms (Figure 2). Additionally, influenced by the warm and moist jet stream at the base of the low vortex, parts of southern Manitoba and Ontario in Canada, and the central and eastern United States will also be affected by severe convective weather, including short-duration heavy rainfall, thunderstorms with strong winds, hail, and tornadoes (Figure 3).

Additionally, on May 26, wildfires broke out in northern Saskatchewan, Canada. Over the next week, cumulative rainfall in these areas is expected to reach 10-30 mm, with localized totals potentially exceeding 50 mm (Figure 1). However, influenced by a low-pressure vortex, southern-central Canada will experience winds of 5-7 on the Beaufort scale, with gusts reaching 8-9 and localized gusts exceeding 10 (Figure 4), posing significant challenges to local firefighting efforts.

Figure 1. 500 hPa Geopotential Height (contours, unit: dagpm) and 850 hPa Wind Field (wind barbs, unit: m/s) over North America at 00:00 UTC, June 2, 2025

Figure 2. Forecasted Accumulated Precipitation from June 1-7, 2025 (Unit: mm)

Figure 3. Forecast of 850 hPa Wind Field (wind barbs, unit: m/s) and K-Index (shaded, unit: °C) for June 3, 2025

Figure 4. Forecast of Maximum Gusts in 24 Hours on June 2, 2025 (Shaded, Unit: m/s)

Author: Huo Da                                 Reviewer: Ma Jie 

English reviewer:Wang Yi                                                                       Issue approver:Dai Kan