ACUS11 KWNS 200220
SPC MCD 200220
Mesoscale Discussion 0110
NWS Storm Prediction Center Norman OK
0820 PM CST Tue Feb 19 2019
Areas affected...Central Missouri
Concerning...Winter mixed precipitation
Valid 200220Z - 200715Z
SUMMARY...Wintry mixed precipitation expected across the area,
beginning with freezing rain/sleet, then transitioning to mainly
rain, from south to north. Some areas may experience brief periods
of heavier freezing rain, with rates up to .05 in/hr. Farther
northwest, snow will be the main precipitation type, with brief
bursts of heavy snow possible.
DISCUSSION...A mid-level vort max embedded within a larger scale
upper-level shortwave trough is currently traversing the area, that
in tandem with strong surface-700 mb WAA, is providing deep-layer
ascent to the region. Tropospheric profiles are mainly below
freezing (per RAP forecast soundings), though the aforementioned WAA
has encouraged temperatures warming to/slightly above 0C around 850
mb, north of the surface wet-bulb 0C line. As such, most dendrites
are expected to melt around 850 mb, before refreezing as ice pellets
in the lowest 100 mb or reaching the surface as freezing rain.
KSGF and KEAX dual-polarimetric radar data suggests that much of the
precipitation, concentrated within a northwest-to-southeast oriented
band, is falling as sleet, though multiple ASOS stations across
southern Missouri are also reporting ice accretion rates over .05
in/hr. As such, brief bouts of heavier freezing rain are also
possible in addition to sleet. Farther northwest towards the Kansas
City Metropolitan area, vertical profiles (via RAP forest soundings)
are colder then points farther southeast, where snow will likely
remain the predominant precipitation type, even with the strong WAA
present. Brief periods of heavy snow cannot be ruled out.
As WAA will continue across the region this evening, surface
temperatures are expected to slowly warm with time,
approaching/rising above the freezing mark, where a transition to
mainly rain can be expected, beginning with the southern most
portions of the discussion area and spreading northward with time.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 37509133 37549230 37969374 38369425 39389484 39939458
40329358 40249278 39809178 39249122 38009063 37509133