Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wichita Kansas
259 PM CDT Thursday Sep 18 2014
Short term...(this evening through saturday)
issued at 254 PM CDT Thursday Sep 18 2014
Weak shortwave in the northwest flow and a somewhat stationary Theta-E
gradient has led to a persistent but diminishing band of
showers/thunderstorms across the Flint Hills. Think this area
of showers will diminish as the afternoon progresses...as the
shortwave continues to drop southeast into NE OK...which will
greatly reduce the lift. Could see some showers linger into the
late afternoon before ending.
After this convection diminishes...think most of the evening and
overnight hours will remain dry...as low-middle level moisture
transport begins to shift well north of the area...as the upper
level ridging increases across the plains.
Think most of the daytime hours on Friday will remain dry as warm
southerly breezes continue across the plains and the upper ridge
moves across the northern plains. This will lead to another above
normal temperature day...as winds shift to the S-SW. Do not believe
temperatures will jump into the upper 90s like Wednesday...as middle-upper cloud
cover will be a little more extensive...but think the warmer NAM/WRF
has the right idea with maximum temperatures in the low 90s. So will adjust maximum
temperatures up some.
Concern for Friday night into Sat will then shift to remnants of the
tropical system Odile...currently spinning over southern nm.
Extrapolation and current European model (ecmwf)/GFS models are taking this system
straight east...or trending it further south...across the Southern Plains
and the Red River of OK. This is further south than previous runs
suggested. The NAM/WRF though still suggests a little further north
track across northern OK...but still further south.
Models to continue to show a nice moisture fetch just to the east
and ahead of this system...even with the more southern shift...but
main area of heavy rainfall may be shifting further south along or
south of the Kansas/OK border. So have adjusted quantitative precipitation forecast and pop values down.
Still think the rest of the forecast area further to the north will
see a chance of showers and some embedded storms...as a shortwave in
the Great Lakes helps push a synoptic cold front south for late Sat
afternoon into Sat night. Convergence and increased moisture will
lead to a solid chance of showers...but just not the heavy rainfall
amounts that were previously suggested. So will keep probability of precipitation solidly
in the chance range for now...even into Sat night...as moisture from
the tropical system rides of the top of the frontal boundary as it
pushes south into OK.
Long term...(sunday through thursday)
issued at 254 PM CDT Thursday Sep 18 2014
Could see some showers linger across southern Kansas for early on sun. But
general trend for the rest of sun through Tuesday will be cooler and
drier weather...as northern plains area of high pressure drops south
across the area....with an upper level ridge over the northern
Upper ridge over The Rockies begins to break down for Tuesday through
Thursday...as a shortwave makes its way east into the plains. Warm
advection and moisture returns to Kansas for late Monday night into Tuesday.
This will lead to a chance of showers and embedded thunderstorms
increasing for the middle of the week.
Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1253 PM CDT Thursday Sep 18 2014
VFR will return to all of the area during the early afternoon
hours as showers and thunderstorms continue to decrease in
coverage and intensity across southeast Kansas. Some transient
areas of heavy rain will continue before the activity diminished
by middle-late afternoon. Low ceilings may return after 07-09z but
confidence in widespread IFR returning across the area remains
low at this time. Low level south/southwest winds should allow any
lingering stratus to mix out by 14-16z on Friday.
Preliminary point temps/pops...
Wichita-kict 69 91 69 83 / 10 10 10 60
Hutchinson 69 90 68 83 / 10 10 20 50
Newton 68 90 68 83 / 10 10 10 50
Eldorado 68 91 68 83 / 10 10 10 50
Winfield-kwld 69 90 69 84 / 10 10 10 60
Russell 67 88 67 83 / 10 10 30 40
Great Bend 67 89 67 83 / 10 10 30 40
Salina 68 87 69 84 / 10 10 20 40
McPherson 68 89 68 83 / 10 10 20 40
Coffeyville 68 89 68 85 / 10 10 0 40
Chanute 67 87 68 85 / 10 10 0 30
Iola 66 87 68 84 / 10 10 0 30
Parsons-kppf 68 88 68 85 / 10 10 0 40