SPC Jun 22, 2019 0100 UTC Day 1 Convective Outlook

SPC 0100Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0744 PM CDT Fri Jun 21 2019

Valid 220100Z - 221200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE TENNESSEE VALLEY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL HIGH PLAINS AND LOWER MISSOURI VALLEY...

...SUMMARY...
Severe storms capable of damaging winds will be possible across
parts of the lower Missouri and Tennessee Valleys into the Southern
Appalachians. Other severe storms will be possible across the
northern Plains and central High Plains.

...Tennessee Valley/Southern Appalachians...
A linear MCS will continue to move southeastward across the
Tennessee Valley early this evening. Strong instability (MLCAPE of
3000 to 4000 J/kg) is analyzed by the RAP ahead of the line. Wind
damage will be likely along the leading edge of the line. A QLCS
tornado may also develop along the more intense part of the line.
The wind damage threat should become more isolated later this
evening as the line moves southeastward into the southern
Appalachians.

...Lower and Mid Missouri Valley...
The latest water vapor imagery shows an upper-level ridge over the
north-central U.S. At the surface, a cold front is located from
eastern Nebraska southward into central Kansas. A moist airmass with
easterly flow is located to the east of the front across the lower
to mid Missouri Valley. Thunderstorms have developed over the last
1-2 hours near a corridor of enhanced low-level convergence in
northeastern Kansas. This convection will spread east-northeastward
into northwestern Missouri early this evening. Convective coverage
should gradually increase across the lower Missouri Valley in the
wake of the upper-level ridge this evening. Strong instability and
moderate deep-layer shear will be favorable for rotating storms with
potential for large hail and wind damage. A brief tornado can not be
ruled out as low-level shear increases early this evening.

...Central High Plains...
The latest water vapor imagery shows  west-southwesterly mid-level
flow over the central High Plains. At the surface, a post frontal
airmass is located in northeastern Colorado and western Kansas.
Surface dewpoints are mostly in the mid 50s to mid 60s F across this
area. A corridor of instability is located from southeast Colorado
into west-central Kansas where the RAP is estimating MLCAPE in the
1500 to 3000 J/kg range. In addition, the WSR-88D VWP at Goodland,
Kansas has 0-6 km near 60 kt. This suggests that supercells will
continue to be possible this evening. Large hail and wind damage
will be the primary threats as the storms move into northwest Kansas
over the next 2 to 3 hours.

...Northern Plains
The latest water vapor imagery shows an upper-level low over
northeastern Montana with southwest mid-level flow over the northern
Plains. At the surface, a cold front is present in eastern South
Dakota. Thunderstorms will continue to develop along the front.  The
RAP has an axis of instability just ahead of the front with SBCAPE
values around 1000 J/kg, confirmed by the 00Z Aberdeen sounding.
This combined with moderate deep-layer shear will be enough for a
marginal severe threat with strong gusty winds and hail possible
early this evening.

..Broyles.. 06/22/2019

Read more

from SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day1otlk_0100.html