Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tulsa OK
1148 am CST Sat Feb 28 2015
concerning taf sites ktul/krvs/kbvo/kmlc/kxna/kfyv/kfsm/krog.
Light to moderate snow will continue to push across northeast
Oklahoma and northwest Arkansas...while snow mixing with sleet
will be possible into the evening hours for southeast Oklahoma and
west central Arkansas. Overnight the mixed precipitation is expected to
lift northward with areas of freezing drizzle possible across the
region into Sunday morning. Varying visible/ceilings from the LIFR to MVFR
should be common through the taf period across all taf locations.
Previous discussion... /issued 1013 am CST Sat Feb 28 2015/
a low pressure system continues to dive southward along the West
Coast this morning while a wave over central Canada begins to drop
southward. This has allowed for more of the southern stream upper
level flow to push over the region with low/middle level southwesterly
flow and increasing warm air advection over eastern Oklahoma and
northwest Arkansas. Thus...in response...light to moderate snow
continues to spread across much of eastern Oklahoma and northwest
Arkansas late this morning.
Latest NAM solution continues to develop a middle level frontogenic
band pushing across far northeast Oklahoma into the afternoon
hours..while the 12z GFS run has backed off some on this compared
to the 06z run. Current thinking is that additional snowfall
amounts of 3-4 inches...with locally higher amounts could be
possible if this band stays together and moves over far northeast
Oklahoma. Across the rest of northeast Oklahoma and northwest
Arkansas an additional 1 to 3 inches could be possible into this
evening. Thus...have upgraded the advisory to a warning for far
northeast Oklahoma and will continue with an advisory for the rest
of the County Warning Area.
Across southeast Oklahoma into west central Arkansas...thickness
values are expected to increase along with a middle level warm nose
this afternoon and evening which will allow for precipitation to become
more of a snow/sleet mix to a possible rain/freezing rain mix.
This mixed precipitation continues to look like it should push northward
through the evening and overnight tonight...with locations along
the Oklahoma Kansas border being the last to switch over to mix
Temperatures this afternoon look to warm little across much of northeast
Oklahoma and northwest Arkansas...with warming closer to/just
above the freezing mark for southeast Oklahoma. Morning update
will be to adjust pop/weather grids and also snow amount grids based on
the mentioned above and latest trends.
Preliminary point temps/pops...
tul 30 28 38 27 / 100 40 40 20
fsm 32 30 43 33 / 60 60 50 30
mlc 33 30 40 32 / 80 50 30 30
bvo 29 23 37 22 / 100 40 40 10
fyv 29 30 41 27 / 80 60 50 30
byv 28 28 39 26 / 80 70 50 30
mko 31 29 39 27 / 90 50 40 30
Mio 29 26 37 24 / 100 50 50 10
f10 32 30 38 28 / 90 40 30 20
hhw 34 31 44 38 / 50 70 30 50
OK...Winter Storm Warning until midnight Sunday for okz054-okz055-
Winter Weather Advisory until midnight Sunday for okz049-okz053-
Arkansas...Winter Weather Advisory until midnight Sunday for arz001-arz002-