ACUS01 KWNS 171944
SPC AC 171942
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0142 PM CST Thu Jan 17 2019
Valid 172000Z - 181200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE GREAT BASIN...
Strong to isolated severe wind gusts will be possible with isolated
thunderstorms across parts of eastern Nevada into western Utah
during the late afternoon and early evening.
Current forecast reasoning is well-described within the prior
outlook; with clearing/modest heating ongoing across Nevada, and
spreading into western Utah at this time, limited risk for
gusty/damaging winds locally remains evident.
.PREV DISCUSSION... /ISSUED 1029 AM CST Thu Jan 17 2019/
...Eastern NV and Western UT...
Guidance differs greatly with the degree and eastern extent of
boundary-layer heating with the NAM substantially cooler than the
RAP, given a pervasive swath of ongoing cloudiness. However,
mid-level drying yielding clearing is evident in satellite imagery
across western NV and this should shift eastward into the afternoon.
In conjunction with mid-level cold-air advection, the setup should
foster increasing destabilization during the afternoon via delayed
boundary-layer heating and lapse rates aloft becoming very steep.
Mid-level DCVA associated with the portion of the shortwave trough
shifting from northern CA into the Great Basin and convergence along
a cold front should yield a broken band of showers with embedded
thunderstorms by late afternoon from the NV/UT/ID border area
south-southwest into east-central NV. 30-40 kt effective shear could
support modestly organized convective structures. Where inverted-v
thermodynamic profiles can develop, strong to isolated severe wind
gusts may occur as activity spreads east before waning this evening.