Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
375 ACUS01 KWNS 131217 SWODY1 SPC AC 131215 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0715 AM CDT Thu Jun 13 2024 Valid 131300Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PORTIONS OF NORTHERN MISSOURI...SOUTHERN IOWA...AND NORTHERN ILLINOIS... ...SUMMARY... Severe thunderstorms are most likely across southern Iowa into northern portions of Missouri and Illinois during the late afternoon to early evening. Very large hail, destructive wind gusts, and a couple tornadoes are possible. ...Great Lakes... Morning water vapor imagery shows a progressive shortwave trough over the Dakotas, with an associated cluster of showers and thunderstorms over eastern SD. This feature will track eastward through the day, with large scale forcing for ascent overspreading parts of southern WI/northern IL and Lower MI by early afternoon. Strong daytime heating in this area will likely result in intensification of thunderstorms along an approaching cold front, in an environment of steep low and mid level lapse rates and moderate CAPE. Activity will spread across Lake Michigan and southern Lower MI through early evening with a risk of hail and damaging winds. ...Middle MS Valley... The aforementioned surface cold front will extend southwestward across southern IA and into northeast KS by mid afternoon. Strong daytime heating will yield afternoon temperatures in the upper 80s to mid 90s ahead of the front, along with a corridor of dewpoints in the mid-upper 60s. Forecast soundings in this zone show large MLCAPE values over 3000 J/kg along with steep low and mid level lapse rates. Convective initiation along the front may be delayed until late afternoon or early evening due to warm temperatures in the 800-700mb layer, but eventually discrete supercells are expected to form along the front. Storms will track east-southeastward across the ENH risk area posing a risk of very large hail, damaging winds, and perhaps a tornado or two. Upscale organization into one or more bowing structures is also expected this evening with an increased risk of damaging winds. ...Western KS to TX Panhandle... A hot and deeply mixed boundary layer will develop this afternoon from the northeast TX Panhandle into western KS, with temperatures over 100F. Most CAM solutions suggest scattered coverage of high-based thunderstorms in this region. Forecast soundings show inverted-v profiles, but also sufficient winds aloft to pose a risk of locally damaging wind gusts for a few hours during the evening. ..Hart/Bentley.. 06/13/2024 $$