Area Forecast Discussion
Issued by NWS Oklahoma City, OK

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FXUS64 KOUN 171140

Area Forecast Discussion
National Weather Service Norman OK
540 AM CST Tue Jan 17 2017

The January 17-18, 12 UTC TAF discussion follows:


An area of ~1500 ft AGL stratus continues to shift southeast this
morning. Expect temporarily to prevailing MVFR ceilings at
KOKC/KOUN/KLAW through ~1300-1330 UTC and KPNC through ~15 UTC.

Otherwise, VFR conditions are expected at all terminals until
this evening. MVFR ceilings are expected to move back into north
Texas this evening and at least the southern half of Oklahoma
tonight. Rain is expected at KSPS this evening and may also
affect or at least be in vicinity of KOKC/KOUN/KCSM/KHBR/KLAW.
There is lower confidence for MVFR ceilings and rain farther
north, so opted not to include in these TAFs for now.

Light northwesterly winds will become variable at most terminals
by this evening.



.PREV DISCUSSION... /issued 340 AM CST Tue Jan 17 2017/

Primary forecast concerns for the upcoming week are precipitation
chances tonight and on Sunday.

A shortwave trough/vort max will lift northeastward tonight into
early Wednesday. Both convective-allowing (3KM NAM/NSSL WRF/TTU
WRF)and parameterized (12 KM NAM/GFS/ECMWF) models are aggressive
with measurable precipitation farther northwest into
central/western Oklahoma. The parameterized models actually have
a distinct QPF maxima across west-central Oklahoma associated
vort max. Though the greatest isentropic ascent is progged to be
near the Red River, DPVA/ascent from the vort max should provide
sufficient lift farther northwest for at least scattered showers
in central and western Oklahoma (as suggested by the convective-
allowing models).

Therefore, opted to increase the chance of precipitation appreciably
from the previous forecast. Still appears the greatest
probabilities for precipitation will be across southern
Oklahoma/western north Texas (in association with the isentropic
ascent) with decreasing probabilities to the north. This is also
where the greatest rainfall totals are expected as well. Elevated
instability is rather meager with perhaps a little (MUCAPE
~100-150 J/kg) near the Red River/western north Texas. Only
included a slight chance of thunder in this area.

Temperature profiles where precipitation is forecast are progged
to be warm enough for liquid for now; however, northern Oklahoma
will have to be monitored carefully. Rain chances a little
farther north (i.e., along the Kansas border) or slightly cooler
temperatures may require an introduction of light freezing rain.

Some lingering showers will be possible across the southeast
on Wednesday; however, for most locations, expect dry weather
and seasonable temperatures. Seasonably warm temperatures are
expected for Thursday through Saturday with highs in the upper 50s
and 60s. Rain chances may begin to increase later Saturday with
the approach of the next system.

A closed mid/upper level low is progged to track across
Oklahoma late Saturday into Sunday. The greatest probabilities
for precipitation will be across northern Oklahoma in association
with the deformation zone; however, some wrap-around
precipitation will be possible farther south into at least
Central Oklahoma. BUFR soundings would suggest any precipitation
will remain liquid. This seems reasonable with no significant
cold air intrusion progged with this system. Therefore, opted not
to include any mention of winter precipitation for now. Dry and
seasonable temperatures are expected in the system`s wake for



Oklahoma City OK  50  37  53  40 /   0  40  10  10
Hobart OK         50  38  54  38 /   0  40  10   0
Wichita Falls TX  52  41  55  40 /  30  60  10  10
Gage OK           48  33  56  35 /   0  20  10   0
Ponca City OK     48  33  52  37 /   0  20  10  10
Durant OK         54  43  52  43 /  20  80  20  10




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