Mesoscale Discussion 17

Issued

Jan 10, 2021, 9:34 AM CST (15:34 UTC)

Expired

Jan 10, 2021, 1:30 PM CST

In force

4 hr

Issued by

the Storm Prediction Center

Concerning

Heavy snow

The Dyess AFB radar (KDYX), 71 km from the middle of the area, began a volume at 15:33 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

860 
ACUS11 KWNS 101534
SWOMCD
SPC MCD 101534 
TXZ000-101930-

Mesoscale Discussion 0017
NWS Storm Prediction Center Norman OK
0934 AM CST Sun Jan 10 2021

Areas affected...Portions of central into north Texas

Concerning...Heavy snow 

Valid 101534Z - 101930Z

SUMMARY...Pockets of 1 inch per hour snowfall will be possible in
portions of the central/north Texas. The highest rates will likely
diminish by mid-afternoon.

DISCUSSION...A band of moderate to heavy snow is ongoing in the the
I-20 vicinity west of DFW, arcing southeastward towards Waco. This
band is primarily being supported by 700 mb warm air advection with
further enhancement from a southeastward progressing shortwave
trough now centered in the Texas South Plains per water vapor
imagery. Into the afternoon, an area of favorable ascent within the
dendritic growth zone is expected to continue moving from the Hill
Country into central Texas. At least brief periods of 1 inch per
hour snowfall rates will be possible. Steep mid-level lapse rates
were observed on this morning's FWD sounding and visible satellite
shows convective turrets along the southern flank of the main
precipitation shield. A few locations may experience locally higher
snowfall rates where convective enhancement occurs. By late
afternoon, snowfall should diminish as 700 mb winds veer and the
main synoptic ascent shifts east.

With low-level dry air also being observed on the FWD sounding, as
well as the southeasterly track of the greatest ascent, the
northward extent of higher snowfall rates is uncertain. While the
DFW metro area is not likely to see the highest snowfall rates,
there will be a period during the early to mid afternoon where the
band of precipitation is able to cool/moisten the low levels and
produce a narrow window of snowfall that approaches 1 inch per hour.

..Wendt.. 01/10/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...FWD...EWX...SJT...

LAT...LON   31539948 31609963 31999991 32500010 32810006 33189972
            33279934 33319865 33069802 32709748 31949665 31449676
            31049719 30979785 31089867 31539948

Mesoscale Discussions in Texas, 2021Every mesoscale discussion in 2021

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.