bubba hotep wrote:Will we see a WPC MD for training sleet today?
Mesoscale Discussion 0118
NWS Storm Prediction Center Norman OK
0718 AM CST Tue Jan 31 2023
Areas affected...southeastern Oklahoma and adjacent west-central and southwestern Arkansas...and southward to central Texas
Concerning...Freezing rain
Valid 311318Z - 311715Z
SUMMARY...Freezing rain, falling at rates in excess of 0.05" per hour, can be expected this morning from central Texas northeastward across southeastern Oklahoma and adjacent portions of Arkansas.
DISCUSSION...Latest surface analysis shows the cold front now over the western Gulf of Mexico, having cleared even deep South Texas. As a result, temperatures across much of the state -- with the exception of the Coastal Plain -- are near or below freezing.
As the western U.S upper system (low centered over far northern Baja at this time) advances slowly eastward, a broad/leading plume of ascent -- evident in water vapor imagery across northern Mexico and the southern Plains, and arcing anticyclonically eastward across the Southeast -- is contributing to the development of convective precipitation across parts of central and northern Texas.
This evolution is fairly well-handled by current CAM runs, which suggest the convection will continue to increase in coverage, and spread northeastward across southeastern Oklahoma with time, and eventually into parts of western Arkansas through late morning/midday.
Morning RAOBs, and model point forecast soundings, reveal warm air aloft and weak instability, atop the sub-freezing boundary layer.
This suggests potential for freezing rain, with rates in excess of 0.05" per hour, including substantially greater rates over short intervals locally, as convective cells shift quickly northeastward.
Freezing rain is being observed at this time across central and northern Texas with this developing precipitation, though parts of western North Texas and into south-central Oklahoma may also experience sleet, given the increasingly deep surface-based layer of sub-freezing air with northward extent.
..Goss.. 01/31/2023