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Area forecast discussion 
National Weather Service Topeka Kansas
335 PM CDT Thursday Jul 30 2015

Short term...(this evening through friday)
issued at 334 PM CDT Thursday Jul 30 2015

Light precipitation lingers south of Interstate 35 this
afternoon...resulting from the overnight mesoscale convective system
over south central Kansas. Weak high pressure behind the old
boundary was over the Central Plains with modest winds...and some
high cloud continues to move through the area from the
southwest...around the upper ridge.

Will continue with a small pop in far southern areas early on...but
weakening trends should continue and allow for dry conditions most
of tonight in modest middle level subsidence. Light winds should be the
rule tonight...though winds off the surface do look a bit higher
than last night and periods of high cloud seem likely so a repeat
event seems unlikely. Southern areas may be the more likely area for
any fog where clouds have prevailed today and should level by
sunset. There continues to be evidence of weak convergence
developing in eastern Nebraska Friday afternoon along a surface
trough/very weak cold front. Instability may be enough to spark a
few storms there which could reach northern areas late in the
afternoon and will continue small chances there. Modest south winds
and continued modification of the old surface high should brings
highs into the lower 90s.

Long term...(friday night through thursday)
issued at 334 PM CDT Thursday Jul 30 2015

Northwest upper flow is expected to persist across much of the
Central Plains through the weekend. Surface high will gradually move
off to the east allowing for return flow across all of eastern
Kansas by Saturday morning.

The chance of thunderstorms continues into the evening hours with
the best chances near the Nebraska border and south of the surface
frontal boundary. Marginal shear along with unstable airmass with
MUCAPE 1600-4000 j/kg in place may produce a few strong to isolated
severe storms with damaging winds and hail the main hazards. Any
storms that develop north of the Kansas border would track southeast
into northeast Kansas. Any overnight convection looks to end by
sunrise Saturday with highs in the upper 80s to lower 90s. Saturday
night the models show a weak shortwave moving southeast in the
northwest flow aloft. After morning lows in the upper 60s highs on
Sunday will top out in the lower 90s.

Models continue to differ with the next shortwave through to move
through the plains Tuesday and Tuesday night. Operational GFS and
ecmef differ with the European model (ecmwf) showing a trough flattening the ridge as
it moves across the plains where the GFS maintains the upper ridge
in The Rockies and northwest flow over the plains. Went with an
ensemble approach and maintained low precipitation chances given the
model differences. The rest of the period will see a couple of
shortwaves move across the plains and bring a chance of
thunderstorms to the area Wednesday through Thursday. Highs Tuesday
through Thursday in the 80s to low 90s.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1231 PM CDT Thursday Jul 30 2015

VFR conditions anticipated. Lower cloud to the southwest appears
to be more isolated to the south and not expected to reach the
terminals. With more insolation today and slightly more boundary
layer mixing not expecting fog to redevelop.


Top watches/warnings/advisories...


Short term...65
long term...53

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