RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Mon Jan 25 12:39:02 UTC 2021.
MD 0028 CONCERNING HEAVY SNOW FOR PORTIONS OF KS AND SOUTHERN NE
Mesoscale Discussion 0028
NWS Storm Prediction Center Norman OK
0458 AM CST Mon Jan 25 2021
Areas affected...Portions of KS and southern NE
Concerning...Heavy snow
Valid 251058Z - 251700Z
SUMMARY...Heavy snow, with rates of 1-2 inches per hour, will likely
develop northeastward across Kansas and southern Nebraska this
morning.
DISCUSSION...Strong forcing for ascent and frontogenetic lift in the
low levels, associated with a northeastward-ejecting shortwave
trough, will aid in the development of a heavy snow band across
parts of KS into southern NE this morning. An initial mix of wintry
precipitation across parts of southwestern into central KS is
expected to quickly transition to snow as low/mid-level temperatures
cool with the approaching shortwave trough. Pronounced lift through
the saturated dendritic growth zone will likely favor heavy snow
with rates of at least 1 inch per hour for several hours in a
southwest to northeast oriented band across KS. Higher rates,
perhaps up to 2 inches per hour, appear possible on a localized
basis. This heavy snow band should shift into parts of southern NE
by mid to late morning. A very narrow corridor of freezing
rain/sleet may occur on the southeastern fringe of the band, where a
modest low-level warm nose should remain.
..Gleason.. 01/25/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OAX...TOP...ICT...GID...DDC...GLD...
LAT...LON 37660004 37430072 38230133 39080121 39970021 40839872
41169726 40999629 40509581 40059572 39659589 39149680
37660004
Read more
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CST Mon Jan 25 2021
Valid 271200Z - 281200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
No severe weather is expected across the U.S. on Wednesday.
...Discussion...
A fast-moving short-wave trough -- progged to be exiting the central
and southern Plains region early in the period, will continue
tracking eastward, clearing the East Coast overnight. Meanwhile,
sharp upper troughing will remain aligned roughly along the West
Coast through the period. In between, ridging aloft will exist,
with anticyclonic flow expanding to include most of the U.S. by the
end of the period, in the wake of the departing eastern system.
At the surface, high pressure will largely prevail over most of the
country. A surface front lying across the Southeast and into the
Gulf will sag southward with time, as a weak frontal wave moves off
the southeastern U.S. coast. Overnight, this front should cross the
Florida Peninsula, reaching far south Florida and the Keys by
28/12Z.
Showers and occasional thunderstorms are expected over portions of
the Southeast, in the vicinity of the aforementioned surface
boundary. Weak instability suggests disorganized -- and for the
most part elevated -- convection. Elsewhere, showers will affect
portions of the West Coast in the vicinity of the nearly stationary
upper trough, but any sporadic lightning flashes inland should
remain few and far between, insufficient for inclusion of a 10%
thunder area.
..Goss.. 01/25/2021
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0346 AM CST Mon Jan 25 2021
Valid 281200Z - 021200Z
...DISCUSSION...
Latest runs of the medium-range models exhibit fair agreement
through the medium-range period, though differences in strength and
timing of the advance of smaller-scale features is evident
throughout the period.
In general however, the period will be characterized primarily by
the slow evolution/migration of a trough -- initially just off the
West Coast -- that is progged to traverse the entire U.S. and reside
near the East Coast at the end of Day 8.
As this system progresses, an associated surface cyclone/frontal
system is forecast to emerge into the Plains by Day 6 (Saturday),
and then shift steadily eastward until moving off the East Coast
late Day 7/Day 8.
Preceding the advance of the surface system however, strong surface
cyclogenesis off the East Coast Day 4 (Thursday) will be followed by
a surge of cold continental air across the eastern U.S. and through
the Gulf of Mexico. This will likely lead to only a very
incompletely modified return of low-level air ahead of the advancing
surface system, and thus likelihood for very minimal instability.
As such, risk for severe weather appears low, through the period.
Read more
|
