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.


Sunday, June 25, 2023

SPC Jun 25, 2023 0600 UTC Day 2 Convective Outlook

LIVE MAP (ABOVE) ... SPC 0600Z Day 2 Outlook Day 2 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0112 AM CDT Sun Jun 25 2023 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA AND VIRGINIA... CORRECTED FOR WORDING ...SUMMARY... A severe threat is expected to develop on Monday across much of the Atlantic coastal states. The greatest severe potential is expected in the Carolinas and Mid Atlantic, where damaging winds and isolated large hail will be possible. An isolated severe threat will also be possible in the northern High Plains. ...Atlantic Coastal States... An unseasonably strong upper-level trough will move eastward into the southern and central Appalachians on Monday. Ahead of the system, a moist and unstable airmass will be in place across much of the Atlantic coastal states. Surface dewpoints in the 60s F, along with surface heating, will result in a large area of moderate instability by midday. During the early afternoon, thunderstorms are expected to form within the higher elevations of the central and southern Appalachians. These storms are forecast to quickly grow upscale, moving into the lower elevations of the Piedmont during the mid to late afternoon. MCS development will be possible as storms congeal into an organized line segment during the late afternoon and early evening. The instability axis is forecast to be located near a pre-frontal trough in the lee of the Appalachians around midday. A consensus of model forecasts suggests the greatest instability will develop from central North Carolina into southern and central Virginia, where MLCAPE values appear likely to reach the 2000 to 3000 J/kg range. In addition to moderate instability, NAM forecast soundings near Richmond, Virginia and Raleigh, North Carolina have steep mid-level lapse rates with relatively cool temperatures aloft. This, combined with 0-6 km shear in the 30 to 35 knot range will likely support supercell development. The potential for supercells will be greatest early in the afternoon, before storms merge into a line. Hailstones of greater than 2 inches in diameter will be possible with supercells that develop in areas that destabilize the most. The current thinking is that a relatively quick transition to a line will occur. This line is forecast to become organized, moving eastward across the Piedmont into the Raleigh/Durham and Richmond areas during the late afternoon. Wind-damage will be likely along the leading edge of the stronger parts of this line segment. The severe threat is likely to extend further north into the Mid-Atlantic, and possibly as far north as southern New England. However, instability is not forecast to be as strong further to the north, suggesting that the threat should be more isolated. ...Northern High Plains... An upper-level ridge is forecast to move across the central and northern High Plains on Monday. Beneath the ridge, a narrow corridor of moderate instability is forecast to develop by afternoon. Surface winds will likely be backed to the east from western South Dakota eastward across much of northern Wyoming, helping to maintain a moist airmass across the northern High Plains. Thunderstorms will develop during the mid to late afternoon in areas that heat up the most. Steep mid-level lapse rates and moderate deep-layer shear will support an isolated severe threat. A few of the stronger cells could produce hail and marginally severe wind gusts. ..Broyles.. 06/25/2023 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)