SPC Aug 5, 2024 2000 UTC Day 1 Convective Outlook
[html]SPC 2000Z Day 1 Outlook

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Mon Aug 05 2024
Valid 052000Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
MINNESOTA INTO PARTS OF THE NORTHEAST...AND OVER A SMALL PART OF THE
COASTAL SOUTHEAST...
...SUMMARY...
Severe thunderstorms remain possible today and tonight from the
Upper Ohio Valley into New England, across portions of the Upper
Midwest, and from northern Florida into southeast South Carolina.
Little overall change to the outlook at 20Z.
An expansive shield of heavy rain stretches from northern FL into SC
in association with Tropical Storm Debby. Low-level shear remains
favorable to support rotation within any stronger embedded cells,
and a brief tornado or two cannot be ruled out. For more information
see mesoscale discussion 1826.
A corridor of strong instability has developed from eastern SD into
northern IL. Storms may develop soon near the SD/MN border, with
east/southeastward development along a warm front. For more
information see mesoscale discussion 1827.
..Jewell.. 08/05/2024
.PREV DISCUSSION... /ISSUED 1115 AM CDT Mon Aug 05 2024/
...FL/GA/SC...
TS Debby continues to track slowly northeastward across northern FL.
Widespread clouds over the eastern semi-circle will suppress
heating/destabilization through the day, although recent trends
suggest some mid-level drying beginning to wrap around the south
side of the system. Despite weak thermodynamics, overall shear
profiles are quite strong and would support a risk of a few
tornadoes through the afternoon and night. The threat will spread
northeastward along the SC coast through the day as well.
...OH to New England...
Fast zonal flow is present today across the Great Lakes and
northeast states today, with a 70 knot mid-level jet max tracking
from eastern ONT into New England this evening. A corridor of
mostly clear skies and strong heating is apparent from northern OH
into NY/PA and much of New England today, where afternoon MLCAPE
values will range from 1000-1500 J/kg. Most 12z model guidance
continues to indicate widely scattered thunderstorms will develop in
this zone, with sufficient vertical shear for a few supercell or
small bowing structures. Mid-level lapse rates are weak, but the
stronger storms may produce locally damaging winds and perhaps hail.
...MN/IA/WI/IL...
Latest surface analysis shows a low over southeast SD, with a warm
front extending east-southeastward from the low across central IA.
Pockets of heating and ample low-level moisture on the north side of
the warm front are expected to result in scattered thunderstorms
(possibly surface-based) by mid-late afternoon over northwest
IA/southwest MN, with storms tracking southeastward along/north of
the front. Large CAPE values, steep mid-level lapse rates, and
substantial vertical shear profiles will promote supercell storm
structures capable of large hail, damaging winds, and a tornado or
two.
...ID/MT...
Water vapor imagery shows a plume of mid-level moisture spreading
northward across ID, ahead of a pair of minor shortwave troughs
moving across NV/OR/WA. This should lead to scattered high-based
showers and thunderstorms this afternoon across much of ID and
western MT. Steep low and mid-level lapse rates will promote a risk
of locally damaging winds in the stronger cells this afternoon and
evening.
Read more[/html]
Source: SPC Aug 5, 2024 2000 UTC Day 1 Convective Outlook (http://ht**://www.spc.noaa.gov/products/outlook/day1otlk_2000.html)