Area Forecast Discussion
Issued by NWS Tulsa, OK
FXUS64 KTSA 261116
Area Forecast Discussion
National Weather Service Tulsa OK
516 AM CST Sun Feb 26 2017
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
Mid and high level clouds will increase during the day. Low
clouds, including potential for IFR ceilings at MLC and MVFR at
the remaining terminals, will develop and spread across the area
during the latter half of the valid TAF period. Scattered showers
will affect parts of SE OK and W AR this evening, with FSM most
likely to see rain at the terminal. Will include a TEMPO mention
at FSM with VCSH at MLC and FYV. Thunderstorm potential is nonzero
at MLC/FSM, but chance below mentionable levels.
.PREV DISCUSSION... /Issued 407 AM CST Sun Feb 26 2017/
Broad fetch of warm advection continues to strengthen over the
region with additional forcing from a wave passing through the
Central Plains resulting in an expanding area of radar returns
over southern KS. As low level profiles saturate this region of
light precip may spread across NE OK and far NW AR through the
morning hours. Deeper moisture currently located over deep S TX
will return northward today as the wave currently off the West
Coast rapidly tracks eastward. This process will support convection
expanding across SE OK and western AR from late afternoon through
Strong zonal flow is now in place across the southern tier States
and will provide an active storm track through mid week. The
aforementioned deeper moisture will be drawn further northward on
Monday. While no obvious forcing mechanism is present at this time
the continued warm and moist low level advection may yield
scattered showers Monday - Monday night.
Low level flow veers slightly on Tues with thermal profiles
continuing to warm and pushing the deeper moisture temporarily
further eastward. Unseasonably warm temperatures are likely Tues
and portions of NE OK may experience heightened fire weather
concerns as humidities will be lowest in this region.
Continued good agreement in a stronger wave entering the High
Plains Tues evening with resultant pressure falls allowing
moisture to spread westward with a dryline sharpening through
central OK. The developing warm sector will be rather broad by
this time and instability will markedly increase as steep lapse
rates spread downstream. By late Tues afternoon the warm sector is
likely to be weakly capped and storms may develop along any
confluent zones east of the more obvious sfc boundaries. The sfc
front associated with the passing wave will overtake the dryline
and sweep through the forecast area Tues night. Storm development
is more likely during this period especially with eastern extent.
Storm mode with any afternoon convection would quickly become
supercellular with all modes of severe weather possible. The
convection more aligned with the front is likely be a series of
broken convective lines. Ambient strong low level shear ahead of
the frontal convection would support both straight line wind and
brief tornadic potential.
Once the front passes more seasonal temps are expected with a dry
pattern prevailing into next weekend.