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.

Tuesday, May 10, 2022

SPC May 10, 2022 2000 UTC Day 1 Convective Outlook

SPC 2000Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Tue May 10 2022 Valid 102000Z - 111200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF NORTHWEST TEXAS AND SOUTHWEST OKLAHOMA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF SOUTHERN AND CENTRAL WISCONSIN INTO SOUTHERN PARTS OF THE UPPER PENINSULA OF MICHIGAN... ...SUMMARY... Scattered severe thunderstorms are likely over parts of the southern High Plains beginning late this afternoon through this evening. Very large hail, isolated severe gusts and a tornado threat are forecast this afternoon and evening over parts of Wisconsin and vicinity. ...Discussion... Only minor changes were made to the previous convective outlook. They are listed as follows: 1) Removed low tornado probabilities near the immediate Wisconsin lakeshore of Lake Michigan. Likewise adjusted the significant hail probabilities to be removed from the immediate coast. 2) Added a small 5-percent tornado probability near the TX Big Bend. A very moist airmass and adequate deep-layer shear for supercells (at least early in the convective lifecycle) will seemingly support a 2-3 hour window of tornado potential with a cyclonically rotating supercell. ..Smith.. 05/10/2022 .PREV DISCUSSION... /ISSUED 1135 AM CDT Tue May 10 2022/ ...Synopsis... Expansive upper ridging is currently in place from the western Gulf of Mexico into southern Quebec, while upper troughing extends from Alberta southwestward into central CA. The upper ridging is forecast to build westward/northwestward into more of the southern/central Plains and Upper MS Valley today, while an upper low embedded within the western CONUS troughing moves from central CA into the Great Basin. Strong southwesterly mid-level flow will persist between these two features, helping to advect a strong elevated mixed layer over a large part of the Plains and MS Valley. Current surface analysis places a low over northeast KS, with a stationary boundary extending northeastward across central IA to another weak low in central WI. A cold front also extends southwestward from this low across southwest KS and into the western OK Panhandle before arcing back northwestward into central CO. A dryline is also apparent, extending from the northeast KS low southwestward into southeast NM before transitioning more southward across Far West TX. The stationary boundary in WI and dryline in TX will both be areas of focus for severe thunderstorms today. ...Southern High Plains... A very moist air mass is already in place across the region east of the dryline, with dewpoints ranging from mid 60s near LBB to the upper 60s at MAF and FST. Strong heating is anticipated today across this air mass, with afternoon temperatures in the upper 80s/low 90s, contributing to very strong buoyancy and limited convective inhibition. A weak shortwave trough evident in water vapor imagery moving out of northern Mexico is expected to interact with this unstable and uncapped air mass, providing the impetus for numerous thunderstorms. Initial development is expected across West TX/Pecos River vicinity, where a few storms may be strong enough to produce very large hail. Weak deep-layer vertical shear, abundant low-level moisture, and steep low-level lapse rates will promote outflow dominant storm structures. Upscale growth into one or more convective lines appears likely as cold pool amalgamate, with the resulting lines propagating northeastward. Severe wind gusts with, some downdrafts potentially reaching 65-kt significant criteria, should accompany this activity. ...WI and vicinity... Mid 60s dewpoints are already in place across much of central and southern WI, in the vicinity of the stationary front mentioned in synopsis. Some further increase in low-level moisture is anticipated throughout the day, with strong diurnal heating also expected. Very strong buoyancy will be in place this afternoon in the vicinity of the stationary boundary and weak surface low forecast to move along the front during the afternoon. Surface convergence in proximity to this low and stationary boundary will be the main stimulant for thunderstorm development today, with large-scale ascent absent amid background height rises. Even so, at least scattered thunderstorm coverage appears likely, amid an environment supportive of supercells. All severe hazards would be possible with these supercells, including very large hail and a tornado or two. Uncertainty remains as to the potential for upscale growth of convection across the region, and the potential for any such activity to coalesce cold pools enough to transition to a forward-propagating complex. Low wind probabilities were extended eastward/southeastward across Lake Michigan into western Lower MI and/or northern IL to account for this potential. Read more CHECK UPDATE ZOOM GRAPHIC