Temps | Gusts | WU KORD KPWK

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




Cardinal SAT


MOBILE DEVICE? Turn sideways. Weather conditions directly above are near Lakefront. Top tabs refer to O'Hare (official).

Archives for the SPC Convective Outlook are updated daily (approximately) with a live map at the beginning of each article. Follow the link at the end of the article to check for current updates on the NOAA/NWS Storm Prediction Center website. Also, see Archives for Chicago's hourly weather data on CARDINAL NEWS Magazine.


Thursday, June 29, 2023

SPC Jun 29, 2023 1300 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 AM CDT Thu Jun 29 2023 Valid 291300Z - 301200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FROM NORTHERN MO TO IL...SOUTHWEST IN AND WESTERN KY... ...SUMMARY... Swaths of damaging winds of 60-80 mph, large hail up to 2.5 inches in diameter, and a couple of tornadoes will all be possible today from northern Missouri into Illinois and adjacent areas of southwest Indiana and western Kentucky. Other severe storms with large hail and damaging gusts will also be possible farther west into the central High Plains. ...MO/IL/IN/KY/TN through this evening... Severe storm clusters, with embedded supercells, have been moving eastward early this morning near KS/NE border and are expected to continue eastward through late morning across northern MO and extreme southern IA, near a stalled front. A moist/unstable air mass is present along and south of the front, with MLCAPE of 3000-4000 J/kg across northern MO, driven by boundary-layer dewpoints in the low-mid 70s beneath midlevel lapse rates of 9 C/km. These favorable thermodynamic profiles will favor continued strong updraft formation within the clusters as they move along the front and the north edge of the warmest elevated mixed layer, coincident with the southern fringe of the stronger midlevel westerlies. Isolated very large hail to 2.5 inches in diameter will be possible through the morning with the supercells, while large DCAPE favors a continuation of severe outflow gusts (60-80 mph). Though the details are still a bit uncertain, there is the potential for some upscale growth into a bowing MCS with swaths of significant wind damage from northern MO into IL and southwest IN. Once the expected MCS reaches central IL, the tendency should be for more southeastward motion with time, around the periphery of the midlevel ridge. The ongoing storms from eastern IL into southwest IN have shown some tendency to cluster this morning, and may persist for a few more hours while moving southeastward toward KY. Rain-cooled air from these morning storms could also provide a corridor for the upstream convection to move along this afternoon. The main threat with the morning storms will be large hail, primarily with elevated supercells, though some wind damage will also be possible. Damaging winds will be the main threat with the expected MCS this afternoon, and a couple of tornadoes may also occur with embedded circulations. ...Central High Plains this afternoon/evening... Post-frontal, upslope flow is established across eastern CO, and low-level moisture has spread west to the Front Range (aided by outflow from overnight storms). Modification of the rain-cooled air and breaks in the low clouds will support moderate buoyancy by mid afternoon (MLCAPE of 1000-2000 J/kg), when thunderstorm development will become more probable immediately east of the higher terrain from CO into southeast WY. The moderate buoyancy and relatively long hodographs with effective bulk shear in excess of 40 kt will support supercells capable of producing large hail of 1-2 inches in diameter. Some upscale growth into a few clusters will be possible this evening, with an attendant threat for isolated damaging winds. Though the details are fairly uncertain, some of the evening convection may persist into the overnight hours across southern NE/northern KS with some threat for isolated large hail/wind damage. ..Thompson/Gleason.. 06/29/2023 Read more CHECK UPDATE ZOOM GRAPHIC
SUNRISE AND SUNSET TIMES IN UTC (if you're not logged in to Google)
CHICAGO UTC-6 during CST (Central Standard Time, e.g., winter)
CHICAGO UTC-5 during CDT (Daylight Savings Time, e.g., summer)