Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tulsa OK
620 am CDT Tuesday Apr 21 2015
concerning taf sites ktul/krvs/kbvo/kmlc/kxna/kfyv/kfsm/krog.
Scattered light rain will be moving across the eastern OK taf sites
this morning...however all categories will remain VFR...with
prevailing VFR conditions expected at taf sites that remain
outside of rain areas....except kmlc may begin to see MVFR ceilings
very late in the period.
Previous discussion... /issued 337 am CDT Tuesday Apr 21 2015/
scattered showers expected to move into the eastern Oklahoma later
this morning in association with upper wave with precipitation
spreading into northwest Arkansas by late morning. Overall...
rainfall amounts are expected to remain fairly light as low level
moisture remains limited.
Strong subtropical jet will continue to strengthen across the Baja California
peninsula tonight spreading into Texas by Wednesday morning. In
response...low level moisture will surge north along/south of
warm front into southern Oklahoma. A few elevated strong to severe
thunderstorms will be possible Wednesday morning with large hail
as steep middle level lapse rates remain in place.
Greater severe threat still appears to be Wednesday afternoon/evening
as convective complex develops west of the area...impacting southeast
Oklahoma and possibly portions of west central Arkansas. Large hail and
damaging winds will be the main threats with a least a limited tornado
threat. Some timing uncertainties still remain including placement
of warm front and any lingering boundaries from the earlier morning
storms...all of which would have an impact on any tornado threat.
The potential for another and maybe more significant round of
severe weather expected on Friday as main upper low ejects into
the Central Plains. Deepening surface low forecast to track out of
southeast Colorado along OK/Kansas state line Friday afternoon/evening.
Again timing will be key...but it appears warm front will lift
north through the area by Friday afternoon with dry line setting
up just west of the area...which would be conducive for all modes
of severe weather.