Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Norman OK
500 am CST sun Dec 28 2014
VFR conditions and light winds expected throughout the taf period.
Westerly and northwesterly winds will quickly shift to southerly
Previous discussion... /issued 424 am CST sun Dec 28 2014/
upper jet induced middle-high clouds expected to continue an eastward
shift through the day today. Light echoes seen earlier near and
south of Wichita Falls evaporated before reaching ground and we do
not anticipate any further development today. As clouds shift east
of snowpack...we should see a fairly significant melt today with
temperatures forecast to reach upper 30s to middle 40s in areas
that saw the snow yesterday. Of course...some shaded areas and
perhaps parts of southwest Oklahoma and North Texas where the
higher totals were seen may see the snow stick around until late
Monday before first in a series of Arctic air surges occur.
The first surge will come on Monday. With upslope flow beneath
fast middle-upper flow...we will keep mention of the possibility of
light snow affecting far western Oklahoma and adjacent parts of
North Texas late Monday and Tuesday. Medium range models
consistent and in good agreement on buckling upper flow over
western U.S. And cutoff upper low approaching late in the week.
Timing/speed of this upper low will be critical on trying to
determine precipitation types with influx of moisture and warm air advection late
Wednesday through Friday. With the good agreement among the GFS
and ecm...with even better agreement between parallel GFS run and
ecm...confidence is higher with potential for mixed
precipitation. It appears as though we could still see a several
hour window of light freezing rain and possibly sleet Thursday
before temperatures warm sufficiently for rain. Outside of perhaps
far northern Oklahoma...forecast soundings do not support any snow
until system exits late Friday night and Saturday. Until then...
we changed the forecast wording to a mixture of rain or freezing
rain before transition to all rain late Thursday night and
especially Friday. Although this currently...and I emphasize
currently...does not appear to be a major ice event...we could
still see a period of glazing due to freezing rain and perhaps
light accumulations of sleet Thursday and Thursday night. Stay
tuned. As mentioned before...as the upper system pulls out late
Friday and Saturday...we could see accumulating snows on the back
side of system...primarily far northern Oklahoma.
Preliminary point temps/pops...
Oklahoma City OK 43 26 46 23 / 0 0 0 10
Hobart OK 44 24 43 20 / 0 0 0 0
Wichita Falls Texas 45 28 51 25 / 0 0 0 0
gage OK 43 15 34 13 / 0 0 0 10
Ponca City OK 41 21 42 19 / 0 0 0 10
Durant OK 45 30 51 29 / 0 0 0 0