Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1241 AM CDT Mon Sep 02 2024
Valid 021200Z - 031200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
TO WESTERN IDAHO AND ADJACENT PORTIONS OF NEVADA AND OREGON...
...SUMMARY...
Isolated to scattered thunderstorms across the northern Great Basin
and parts of the Pacific Northwest may be capable of strong to
severe wind gusts this afternoon and evening.
...Synopsis...
Recent water-vapor imagery depicts a dominant upper ridge centered
over the central CONUS. Flanking the ridge is a departing upper
trough across the lower Great Lakes/Northeast and a more compact
shortwave trough off the northern California coast. This upper-air
regime will largely remain intact for the next 24 hours as the
Northeast upper wave continues to move into the western Atlantic and
the CA shortwave migrates towards the northern Rockies. At the
surface, a slowing cold front draped from the Northeast into the
southern Plains will continue to meander south through the day as a
surface high builds over the Midwest. Isolated to scattered
thunderstorms will be possible along this front and in the vicinity
of a weak mid-level disturbance over western TX; however, weak flow
aloft will hinder the potential for organized convection. Across the
West, thunderstorms, including a few strong to severe storms, are
expected ahead of the upper trough as it moves onshore over the next
24 hours.
...Nevada into eastern Oregon and Idaho...
A modest plume of monsoonal moisture has been tracked from southern
AZ into northern NV/eastern OR over the past few days, and has
resulted in multiple rounds of thunderstorms across the Great Basin
despite very limited low-level moisture and only modestly cool
mid-level temperatures. These conditions were well-sampled by the 00
UTC MFR sounding, which depicts around 250 J/kg MLCAPE atop a very
deep, dry boundary layer. This profile will be typical this
afternoon across the region as ascent associated with the
approaching wave overspreads the northern Great Basin/Pacific
Northwest. Despite minimal buoyancy, LCL heights between 3-4 km will
foster ample evaporative cooling of convective downdrafts that will
support strong downburst winds. Increasing flow throughout the
column will improve wind shear within the CAPE-bearing layer,
promoting better storm longevity and organization (and hence a
higher potential for producing strong/severe wind gusts) compared to
previous days. Recent CAM solutions also hint at this potential with
several HREF members showing isolated swaths of severe winds across
northern NV into central and western ID and eastern OR.
..Moore/Kerr.. 09/02/2024
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TChR76
