Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 PM CDT Wed Jul 08 2020 Valid 090100Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF NEBRASKA THROUGH NORTHEASTERN KANSAS... ...SUMMARY... Severe thunderstorms remain likely this evening and tonight across parts of the central Great Plains into the Upper Midwest. Damaging wind and large hail are the primary threats, through a couple of tornadoes are possible through mid evening. ...Central Plains... Thunderstorms are in the process of developing along a slow-moving cold front from southeast SD through northern NE and some distance south along a pre-frontal trough. The atmosphere is very unstable in this region with very steep 8-8.5 C/km lapse rates and 3000-4000 J/kg MLCAPE. This area resides just south of the stronger mid to upper westerlies, but effective bulk shear from 30-40 kt will support both multicell and some supercell structures with initial discrete storms. Some increase in hodograph size will occur as the low-level jet strengthens, and a small window will exist for a landspout or brief tornado or two this evening, but large hail and downburst winds are the primary threats. A strengthening southerly low-level jet will foster the development of additional storms that will likely evolve into an organized MCS. This activity will advance south and southeast through the central Plains tonight with primary severe threat transitioning to damaging wind. ...Upper Midwest... Storms are currently developing across MN in vicinity of a cold front as well as in association with a northeast-advancing MCV. The atmosphere is very unstable in this region with 3000+ J/kg MLCAPE along with 25-35 kt effective bulk shear. Some increase in low-level hodograph size will occur as the low-level jet strengthens and a brief tornado or two remain possible as storms move northeast and interact with warm front. However, damaging wind and large hail will remain the primary threats before activity weakens later tonight. ..Dial.. 07/09/2020Read more
from SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day1otlk_0100.html
No comments:
Post a Comment