Mesoscale Discussion 50

Issued

Jan 15, 2017, 9:02 AM CST (15:02 UTC)

Expired

Jan 15, 2017, 2:00 PM CST

In force

5 hr

Issued by

the Storm Prediction Center

The Topeka radar (KTWX), 75 km from the middle of the area, began a volume at 15:02 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.

300 
ACUS11 KWNS 151502
SWOMCD
SPC MCD 151502 
MOZ000-IAZ000-KSZ000-NEZ000-152000-

Mesoscale Discussion 0050
NWS Storm Prediction Center Norman OK
0902 AM CST Sun Jan 15 2017

Areas affected...Portions of southern NE...northern KS...northern
MO...southwestern IA

Concerning...Freezing rain 

Valid 151502Z - 152000Z

SUMMARY...Areas of freezing rain are forecast to develop
northward/northeastward across portions of the central Plains toward
the lower MO and middle MS Valley region through the day.

DISCUSSION...Ongoing precipitation from east-central CO eastward
through central KS and MO lies within a region of weak elevated warm
advection. As a midlevel cyclone -- presently south of El Paso TX
per water vapor imagery -- continues advancing eastward and then
northeastward, a low-level jet over the southern Plains will
gradually intensify and advance eastward/northeastward. In turn, the
zone of ascent supporting this precipitation will gradually shift
northward during the next several hours. Initial areas of
precipitation crossing southeast NE, northwest MO, and southwest IA
are contributing to low/midlevel saturation, while the
aforementioned ongoing precipitation should overspread the area
within the next few hours, and continue into the afternoon. An
elevated warm layer (temperature around 6.5C at 850 mb at Topeka per
12Z sounding) will generally support complete melting of descending
hydrometeors, which will re-freeze within the sub-freezing surface
layer. Freezing rain, with rates of 0.02 to locally 0.05 inch per
hour, will be possible. Somewhat cooler profiles aloft with
northward extent (e.g., as sampled at Omaha NE at 12Z) may support
initial instances of sleet from parts of southern NE through the
lower MO Valley.

..Cohen.. 01/15/2017

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

ATTN...WFO...LSX...DMX...EAX...OAX...TOP...ICT...GID...LBF...
DDC...GLD...

LAT...LON   38799711 39380082 40200139 40689930 40849538 40239256
            39229161 38769252 38799711

Mesoscale Discussions in Kansas, 2017Mesoscale Discussions in Missouri, 2017Mesoscale Discussions in Nebraska, 2017Every mesoscale discussion in 2017

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.