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fxus63 ktop 151048 

Area forecast discussion
National Weather Service Topeka Kansas
548 am CDT sun Sep 15 2019

..update to aviation forecast discussion...

Short term...(today and tonight)
issued at 245 am CDT sun Sep 15 2019

Several mid-level, weak vorticity maxima are observed shifting
eastward through the Midwest region this morning. Elevated showers
and storms as a result have developed over portions of northwest
Missouri and our County Warning Area within the past hour. Despite the low signal
from short term models, infrared satellite imagery is depicting cooling
cloud tops from Jackson through Morris counties. Isolated showers
and thunderstorms should continue to develop through sunrise before
dissipating as the low level jet weakens. Storms are not expected to
be severe with much of the speed shear associated with the low level jet in
the lower levels. Main hazards are isolated strong wind gusts and
lightning. Midlevel clouds clear out by early afternoon, leading to
another warm and humid afternoon. Sided closer to consraw guidance
on temps, especially given that we are starting out warmer with lows
and strong boundary layer mixing up to 850 mb should lend to warmer
temps compared to Saturday. Overall forecast highs range in the low
to mid 90s.

Upper ridge expands northward this evening, giving way to clear
skies overnight. Meanwhile, northeast Kansas remains wedged between
an area of sfc high pressure to the southeast and the Lee trough
towards the western High Plains. South winds from east to west
increase from calm up to 10 mph in north central areas. Monday
morning lows are generally around 70 degrees.

Long term...(monday through saturday)
issued at 245 am CDT sun Sep 15 2019

Dry and warm weather persists through Wednesday as the upper ridge
amplifies in response to the deepening upper trough over the western
Continental U.S.. current pops in the forecast remain low beginning late
Tuesday Onward, given the high variability in guidance. All guidance
with the exception of the European model (ecmwf) signal the leading upper trough to
lift into the northern plains Tuesday evening, developing a line of
storms along a cold that sweeps across northern Kansas on Wednesday
morning. The European model (ecmwf) brings the weak front through northern Kansas by
late afternoon Wednesday with the focus for redevelopment being near
the boundary. With the vicinity boundary and several mid level waves
lifting out of the main system Thursday through Saturday, it seemed
reasonable to keep the low chance pops in each period, especially
given the differing solutions. For this forecast, it appears that
Saturday afternoon and evening is depicting a similar signal in the
main upper low occluding into far northern Dakotas, sending a
stronger cold front through the region. Higher pops were mentioned
for this period. A cooler, more seasonable airmass returns to the
area by Sunday. While a few stronger storms are possible throughout
the week, very weak effective bulk shear will preclude a widespread
severe threat.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 520 am CDT sun Sep 15 2019

VFR to continue at ktop/kfoe/kmhk. Low level wind shear is observed near 1200 feet
up to 45 kts through 14z. Mid clouds are forecast to scatter out
by late morning with gusty southwest winds during the afternoon.


Top watches/warnings/advisories...

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