This Week in Weather — August 16, 2026

Rearview

The week's defining number is 2,561 — wind reports logged by the Storm Prediction Center from Sunday through Saturday, a figure that dwarfs the 307 hail reports and underscores a pattern dominated by linear, fast-moving convection rather than discrete supercell activity.

The most concentrated severe weather episode came overnight Saturday into early Sunday. Between 8:27 p.m. and 11:04 p.m. EDT on August 15, the Cincinnati forecast office (ILN) issued six tornado warnings across Champaign, Logan, Franklin, and Fairfield counties in Ohio — multiple warnings targeting Champaign County alone within a 30-minute window. The tight clustering of warnings from a single office over a single county cluster signals a fast-tracking, possibly cyclic convective system threading through central Ohio's agricultural corridor.

Wikimedia Commons

Nebraska's Panhandle saw a separate tornado warning at 7:35 p.m. CDT August 15 covering Garden, Grant, and Sheridan counties — sparse, wide-open terrain where population is thin but the convective environment was clearly supportive.

Storm report totals by state tell a regional story: Virginia led at 314, followed by Ohio (277), Indiana (273), Illinois (258), and West Virginia (221). The concentration across the Ohio Valley and mid-Atlantic points to a sustained corridor of Gulf moisture and shear that persisted for multiple days, not a single-day event.

The week's most significant seismic event had nothing to do with the atmosphere. A M7.7 struck 68 km NNW of Ende, Indonesia on August 14 at 9:58 p.m. local time — the largest earthquake globally in the past seven days, occurring along the Flores Sea's seismically active subduction zone. A separate M6.9 hit near Pematangsiantar in northern Sumatra within the same period, and a M5.2 rattled Otura, Spain — a reminder that the Iberian Peninsula sits atop the diffuse boundary between the African and Eurasian plates. Space weather was quiet: maximum Kp of 0, with the sun's most energetic recent flare reaching only C4.4.

Wikimedia Commons

Roadmap

The week ahead is organized around a persistent upper-level ridge anchored over the southern tier of the country, with its western flank suppressing convection from Dallas to Denver while its eastern flank allows disturbances to ride along the ridge's periphery into the Midwest and Northeast. The pattern is not monolithic — a shortwave is already digging into the central plains as of Sunday, and a secondary feature is expected to follow mid-week — but the ridge is the dominant actor.

NOAA NESDIS

South Plains and Mountain West: Dallas averages 106°F through the week with essentially zero precipitation probability at any point. This is not an anomaly — it's the southern ridge doing exactly what it does in August — but 106°F sustained over seven days is a physiological threshold for outdoor workers and vulnerable populations in cities where nighttime lows may only drop to the low 80s, offering minimal recovery time. Denver sits at 94°F average high with a sparse 0.04" of precipitation expected; the 42% peak probability on August 19 likely reflects the standard diurnal cycle over the Front Range, where afternoon surface heating triggers convective initiation over the Rockies and cells drift eastward. Don't expect organized severe weather from that setup — isolated pulse storms are the more probable outcome.

Midwest: Chicago's 73% precipitation probability on August 16 is the highest in the CONUS outlook, and 1.73" of weekly total precipitation is substantial. The shortwave digging through the central plains is the mechanism — it undercuts the ridge's western edge and provides the lift needed to tap Gulf moisture that has been streaming northward along the ridge's eastern periphery all week. Given the SPC data showing Indiana and Illinois both logged over 250 storm reports in the past seven days, the convective environment in this corridor remains primed. Flash flooding is a legitimate concern wherever training convection develops over saturated soils.

Northeast: New York City averages 84°F with 0.80" of precipitation and a 63% probability peak on August 17 — Sunday into Monday. The shortwave that moves through the Midwest on Sunday likely weakens as it tracks east but retains enough forcing to generate showers and isolated thunderstorms across the mid-Atlantic and southern New England by Monday. Not a major severe weather setup, but enough instability behind the front to produce gusty, locally damaging storms given the residual shear.

Southeast: Atlanta sits at 98°F average high with only 0.35" expected. The ridge suppresses convection through most of the week, with the 42% peak on August 21 likely tied to a weak disturbance working along the Gulf Coast. The sea-breeze convergence zone will drive isolated afternoon storms along the Florida peninsula regardless of the synoptic pattern, but organized convection for the broader Southeast is unlikely before the weekend.

International: London averages 74°F — a number that would be unremarkable almost anywhere in the continental U.S. but sits comfortably above London's August climatological mean of around 70°F. The North Atlantic jet stream has been displaced northward this summer, allowing the Azores High to extend its influence farther into western Europe and reducing the frequency of Atlantic frontal passages that would otherwise moderate temperatures.

Eyes on the Sky

• The 73% precipitation probability for Chicago on August 16 is not a background-noise figure — anyone with outdoor events, construction schedules, or agricultural operations in northern Illinois and Indiana should treat Sunday as a likely convective day and check for flash flood watches before committing to plans.
• The Ohio Valley has now generated concentrated tornado warning clusters on multiple nights this week; if you live in central or southern Ohio, the convective pattern has not reset — residual instability and continued Gulf moisture transport keep the severe weather window open into early this week.
• The M7.7 near Ende, Indonesia warrants continued monitoring for aftershocks; the Flores Sea is structurally capable of generating tsunamigenic events, and PTWC advisories should be followed if additional large aftershocks occur in the 48 hours following the mainshock.