• SPC - No MDs are in effect as of Fri Oct 23 05:44:02 UTC 2020
    on October 23, 2020 at 5:43 am

    No Mesoscale Discussions are in effect as of Fri Oct 23 05:44:02 UTC 2020.

  • SPC - No watches are valid as of Fri Oct 23 05:44:02 UTC 2020
    on October 23, 2020 at 5:43 am

    No watches are valid as of Fri Oct 23 05:44:02 UTC 2020.

  • SPC Oct 23, 2020 0600 UTC Day 2 Convective Outlook
    on October 23, 2020 at 5:43 am

    SPC 0600Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 AM CDT Fri Oct 23 2020 Valid 241200Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous U.S. on Saturday. ...Synopsis... Broad cyclonic mid-level flow will encompass much of the northern tier of states on Saturday. A cold front will push eastward across the Northeast. The trailing portion of the front will weaken during the period as it moves southeast across the southern Appalachians and lower MS Valley. Farther west, surface cyclogenesis will occur in the central High Plains during the day, and the trailing portion of the front over the lower MS Valley will advance northward as a warm front over the southern Great Plains. A cold front will push southward over the central High Plains during the evening/overnight. Scattered showers and isolated thunderstorms are possible from the northeast Gulf Coast into the southern Appalachians/VA during the day. Relatively weak large-scale forcing and limited instability will likely preclude strong thunderstorms from developing. The shower/thunderstorm activity will diminish by the early evening hours. ..Smith.. 10/23/2020 Read more

  • SPC Oct 23, 2020 0600 UTC Day 1 Convective Outlook
    on October 23, 2020 at 5:37 am

    SPC 1200Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1229 AM CDT Fri Oct 23 2020 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE LOWER GREAT LAKES INTO THE OHIO VALLEY... ...SUMMARY... Threat for a few severe storms capable of damaging wind, hail and perhaps a tornado or two will exist this afternoon into the early evening over a portion of the lower Great Lakes and Ohio Valley. ...Lower Great Lakes and Ohio Valley region... A mid-upper speed max situated within the base of a synoptic trough will move through the Great Lakes today. Accompanying weak surface low will develop northeastward through the Great Lakes this morning with a moist warm sector (low to mid 60s F dewpoints) advecting into the southern portion of lower MI. Cold front trailing from the low will reach Lake Erie southwestward into the lower MS Valley by early evening. Diabatic warming of the surface layer and modest mid level lapse rates will promote moderate instability in pre-frontal warm sector with 1500-2000 J/kg MLCAPE possible. Vertical shear will strengthen as the upper jet advances through the Great Lakes with 40-45 kt effective bulk shear along with 200-300 m2/s2 0-1 km storm relative helicity, especially from northern IN into southern lower MI. Elevated storms should be ongoing in post-frontal region during the morning. However, surface-based storms are expected to develop along the cold front from southern lower MI into IN as it encounters an increasingly unstable boundary layer this afternoon. Vertical wind profiles will be sufficient for organized structures, especially with storms that can be sustained for a while along the advancing cold front before potentially being undercut. Damaging wind and hail are the primary threats, but a tornado or two will also be possible. ..Dial/Cook.. 10/23/2020 Read more

  • SPC Oct 23, 2020 0100 UTC Day 1 Convective Outlook
    on October 23, 2020 at 1:04 am

    SPC 0100Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0756 PM CDT Thu Oct 22 2020 Valid 230100Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS A PORTION OF THE MIDWEST AS WELL AS THE SOUTHERN PLAINS... ...SUMMARY... A few strong storms with mostly a threat for marginally severe hail are possible this evening, mainly from eastern Iowa into northwest Illinois and southern Wisconsin. Other storms capable of marginally severe hail may occur later tonight across a portion of southeast Oklahoma into north central Texas. ...Midwest through a portion of the upper Great Lakes... Have downgraded to MRGL category this update. The severe weather parameter space is conditionally favorable for severe storms in warm sector, with strong vertical shear profiles and large low-level hodographs along with moderate instability based on the 00Z RAOB from Davenport IA. However, with modest inversion present near 700 mb and a stabilizing surface layer, it appears forcing will remain insufficient to initiate storms away from the cold front which currently extends from eastern IA southwestward through eastern KS. Numerous storms will continue developing this evening primarily in post-cold frontal region as well as north of a warm front across WI. These storms will be elevated, but sufficient instability and lapse rates exist for at least a marginal hail threat with the stronger storms. ...Southeast Oklahoma through north central Texas... Evening RAOB data show a capped atmosphere across OK into north central TX with steep lapse rates above a moist boundary layer. Satellite imagery indicates a shortwave trough located across western TX and forcing for ascent accompanying this feature will interact with a southward surging cold front across this region later tonight, likely resulting in the development of thunderstorms. While vertical shear will remain weak and supportive of multicells along the front, steep lapse rates and moderate instability suggest a few of the stronger storms could produce marginally severe hail. ..Dial.. 10/23/2020 Read more