Area Forecast Discussion
Issued by NWS Topeka, KS
FXUS63 KTOP 282343
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
643 PM CDT SAT MAY 28 2016
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Sunday)
Issued at 322 PM CDT SAT MAY 28 2016
The upper trough has finally lifted northeast into IA and southern
MN this afternoon. There may be enough weak ascent and residual
moisture on the southwest extent of the H5 trough axis for some
isolated showers or thunderstorms along the NE border across
northeast KS late this afternoon. If any showers do develop in
extreme northeast KS they will dissipate by sunset.
Tonight will be mostly clear. If overnight lows drop to the cross
over temps we may see some patchy dense fog develop, especially in
low-lying areas and along lakes and rivers.
Sunday, any patchy fog that develops during the early morning hours
will mix out by 8 AM. A lee surface trough will deepen across the
high plains. As the lee trough deepens, southerly surface winds
will gradually increase to 10 to 20 MPH during the afternoon hours.
As deeper moisture advects northwestward into western and central KS,
there could be a chance for isolated showers and thunderstorms to
develop across the western counties of the CWA during the late
afternoon hours. These storms will not be severe as the vertical
windshear will be weak. Highs on Sunday will warm into the lower to
.LONG TERM...(Sunday Night through Saturday)
Issued at 322 PM CDT SAT MAY 28 2016
Dry conditions are expected Sunday morning across the outlook area,
however expect precipitation chances to return to the area by Sunday
afternoon/evening. An embedded shortwave should develop near the
Texas/Oklahoma panhandles Sunday afternoon and lift northeastward
toward the area by late afternoon/early evening. This advancing wave
will help to lift the frontal boundary currently draped across
Oklahoma northward as a warm front into central Kansas. The
combination of this front and the nearby shortwave will help to
provide enough moisture and lift to produce some scattered showers
and thunderstorms across the outlook area Sunday afternoon through
Monday. This surface boundary should become more north-south
oriented by Tuesday morning across central Kansas, so this lingering
boundary along with the development of additional embedded
shortwaves should result in ongoing periods of scattered showers and
thunderstorms Monday night through Tuesday. Decent mid-level lapse
rates should be in place over the area Sunday through Tuesday,
resulting in modest MUCAPE values of 1000-3000 J/kg. However, 0-6km
bulk shear values looks quite weak at 25kts or less. As a result,
the potential for any strong to severe storms is low at this time.
While overall QPF amounts are fairly low due to the expected
scattered nature of the precipitation, some locally higher
precipitation amounts will be possible with any thunderstorms that
develop and could potentially cause some flooding concerns due to
the high rainfall amounts we`ve received within the last week. As
for temperatures, highs should reach into the mid 80s on Sunday
before the cloud cover builds in with the approaching shortwave.
Slightly cooler conditions are expected on Monday and Tuesday with
the scattered precipitation in the area, but high temperatures
should still reach into the mid 70s to low 80s.
During the latter part of the short work week ahead will see a
deepening upper level low advect over the Northern Plains into the
Upper MS Valley. The associated trough will dig into the Central
Plains and over our forecast area through the day Wednesday and help
to push the cold front along at the surface. Deep layer shear
appears weak over the area as the main forcing resides off to the
north and northeast of the forecast area as the upper level low
lifts off into Canada. However, some afternoon heating could cause
general instability with dewpoints generally in the 60s, which could
bring some afternoon showers and thunderstorm chances. Depending on
the actual strength of the cold front, will have to see if the
environment could support isolated strong multicellular storms.
Therefore, have left chance POPs in the forecast for Wednesday.
After Wednesday, all indications line up to support a mostly drier
pattern as the Canadian/GFS/ECMWF agree that a large Western CONUS
ridge will build in by Friday. Temps should be fairly comfortable
with highs in the mid to upper 70s and lows in the upper 50s.
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 643 PM CDT SAT MAY 28 2016
VFR conditions should the be rule. Clearing skies, light winds,
and wet ground present some opportunity for ground fog. At this
point crossover temps look to only be approached with still some
wind off the surface so only went with MIFG.