DarkSky Temps | Gusts | WU KORD Data

CLICK for this month's BIG night sky ...




Cardinal SAT


Weather conditions on bar directly above are near Lakefront. Tabs under Moon Phases refer to O'Hare (official).

Archives for SPC Convective outlook are updated daily with a live map a the beginning of the article. Touch or click map to get possible update, and follow link at end of article for referral to NOAA/NWS Storm Prediction Center. Archives for Chicago's hourly weather data were updated 24-48 hours after end of each day prior to Dec. 2020.

Sunday, May 15, 2022

SPC May 15, 2022 Day 4-8 Severe Weather Outlook

Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0405 AM CDT Sun May 15 2022 Valid 181200Z - 231200Z ...DISCUSSION... Global models appear to be in reasonably good agreement through Day 6 across the U.S., moving a mid-level trough out of the Gulf of Alaska and into/across the Pacific Northwest Day 4/Wednesday, and then eastward into the northern Plains Day 5/Thursday, and then the Upper Great Lakes/Upper Midwest and into Ontario Day 6/Friday. As the upper system advances, a cold front is forecast to emerge from the northern Rockies into/across the northern and eventually the central Plains. Near this front and the evolving surface low, focused ascent across the north-central States/Upper Mississippi Valley region will likely result in afternoon/evening severe storms. Along with potential for large hail and damaging winds, a few tornadoes are also expected, given flow expected to veer favorably through the lower half of the troposphere, while increasing in magnitude with height, suggesting shear favorable for supercells. Some severe risk may also evolve eastward across the Midwest/Ohio Valley region, as a weak mid-level disturbance moves through westerly flow aloft, near a weak west-to-east baroclinic zone. However, with the north-south positioning of this boundary uncertain, and differing rather substantially in various models, will not highlight this more uncertain risk with a 15% area at this time. Steady advance of the upper trough, and associated cold front, will continue Day 6, with the boundary forecast to extend from the Upper Great Lakes to the southern Plains through the afternoon. Once again, a favorably moist/destabilizing warm sector will lead to severe-storm development near and ahead of the front, as the eastern fringe of stronger southwesterlies aloft spread atop the frontal zone, yield shear sufficient for organized/rotating storms. Large hail and damaging winds would appear to be the primary risks, along with some potential for tornadoes. As model solutions deviate Day 7, mainly with respect to the portion of the trough trailing southward out of eastern Canada into the U.S., convective evolution becomes more uncertain, precluding any areal highlights through the end of the period. Read more CHECK UPDATE ZOOM GRAPHIC