Temps | Gusts | WU KORD Data

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.

Friday, June 4, 2021

SPC Jun 4, 2021 2000 UTC Day 1 Convective Outlook

SPC 2000Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Fri Jun 04 2021 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE MID-ATLANTIC AND THE NORTHERN PLAINS... ...SUMMARY... Severe thunderstorms are possible across the Mid-Atlantic and from parts of central Montana to extreme northwest Minnesota this afternoon and evening. Damaging wind gusts are expected to be the primary risk in these areas. The primary change to the outlook was to add 15% wind probabilities to portions of eastern Pennsylvania, New Jersey, and adjacent portions of New York/Connecticut. An organized line of storms has developed and will pose a threat for damaging wind gusts before moving offshore within the next 2-4 hours. ..Wendt.. 06/04/2021 .PREV DISCUSSION... /ISSUED 1134 AM CDT Fri Jun 04 2021/ ...Northern Plains... Isolated to widely scattered thunderstorm clusters are expected to develop this afternoon into evening near the front over North Dakota, and over higher terrain in southwest Montana. Activity should move generally eastward to east-northeastward over the outlook area, offering sporadic severe wind gusts. Isolated large hail also may occur, especially across Montana where strong mid-level lapse rates will overlie at least marginal inflow-layer moisture content, in a regime of favorable deep/speed shear. Across the entire corridor, diurnal heating will foster very deep, well-mixed sub-cloud/boundary layers with almost dry-adiabatic lapse rates. Resulting high-based convection will pose a threat for severe gusts that may persist into the overnight, before diabatic stabilization of the boundary layer finally becomes too strong to support the threat for damaging gusts to penetrate to the surface. ...Coastal Carolinas and Mid-Atlantic/Northeast States... As residual cloud cover/morning precipitation exits parts of the Eastern Seaboard, weak to moderate destabilization is expected to take place near/east of a surface trough. While isolated/locally severe storms capable of mainly wind damage will be possible across a broad expanse from the coastal Carolinas into southern New England, the most favorable collocation of deep-layer shear/moderate instability is expected to materialize across southern Maryland/southeast Virginia this afternoon, where some more organized/sustained multicellular clusters and bands are possible. ...Upper Texas coast/southwest Louisiana... On the eastern periphery of the residual low across Texas, a moist environment with veering winds through the lower troposphere could yield a couple of strong storms with weak/transient rotation this afternoon through early evening. However, the potential for organized severe storms currently appears low. Read more LIVE: