Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0756 PM CDT Sat Apr 13 2024

Valid 140100Z - 141200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING
ACROSS PARTS OF SOUTH CENTRAL OREGON...

...SUMMARY...
Isolated strong thunderstorm development remains possible into this
evening across parts of south central Oregon, to the north and east
of the Klamath Falls vicinity, posing at least some risk for severe
wind and hail.

...01Z Update...

...Southern Oregon...
As a deep surface low migrates northward to the lee of the northern
Sierra Nevada, forcing for ascent, aided by downstream low-level
warm advection, may maintain vigorous thunderstorm development to
the north and east of the Klamath Falls vicinity into the 02-04Z
time frame.  Based on latest objective analysis, at least a small
pocket of moderate boundary-layer instability persists across this
region, in the presence of marginally sufficient shear for
occasional supercell structures posing at least some risk for severe
hail and wind.

...Great Lakes...
In advance of a digging low-amplitude short wave trough and
associated developing surface low, models suggest that warm
advection along a strengthening frontal zone may contribute to weak
destabilization tonight.  Forecast soundings suggest that moisture
return within and/or above elevated mixed-layer air emanating from
the northern Great Plains will be sufficient to support convection
capable of producing lightning, which may commence across northern
Wisconsin/adjacent upper Michigan by 04-05Z, before spreading
east-southeastward overnight.  Although southwesterly to westerly
wind fields are forecast to strengthen in excess of 50 kts in the
dry sub-cloud air, potential for downward mixing of this momentum to
the surface will tend to be inhibited by a near-surface inversion
layer.  This will remain more pronounced with eastward extent across
northern lower Michigan toward the eastern Lake Erie/western Lake
Ontario vicinity, but occasional gusts approaching severe limits
might not entirely be out of the question.

...Black Hills vicinity into mid Missouri Valley...
In advance of a developing, southward advancing cold front,
a seasonably warm and deeply-mixed boundary-layer became
sufficiently unstable to support widely scattered weak thunderstorm
activity late this afternoon.  This continues in spots, but appears
to be diminishing with the loss of daytime heating, and thunderstorm
probabilities will be maintained at less than 10 percent through the
remainder of the period.

..Kerr.. 04/14/2024