507 
FXUS63 KTOP 270454
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1154 PM CDT Mon Aug 26 2019

.UPDATE...
Issued at 800 PM CDT Mon Aug 26 2019

With the H850 trough having passed through the area, the threat
for thunderstorms has shifted south and east of the forecast area.
Have removed mention of storms from the grids and products. Fog
threat seems very limited in scope and coverage given the 2-4 mb
pressure difference across the forecast area through the overnight
hours and ongoing negative theta-e advection. Winds at the top of
the very shallow BL inversion should remain in the 10 to 15 kt 
range, which should help keep the airmass mixed enough to hinder 
fog formation.

&&

...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Tuesday)
Issued at 332 PM CDT Mon Aug 26 2019

A surface cold front is moving eastward across the forecast area 
this afternoon. As of 20Z, the front was located from around 
Hiawatha to just east of Manhattan to near Council Grove. 
Thunderstorms will likely develop along the front, but there remains 
some uncertainty as to exactly where and when storms will 
initiate. This morning's convection left an area of cloud cover 
over the region and expected instability has not been realized so 
far today. The HRRR now confines the best surface based 
instability to areas along and southeast of I-35, where the model 
shows over 3000 J/Kg of CAPE with no inhibition at 21/22Z ahead of
the front. The RAP has also started to trend southward with the 
best dynamics for thunderstorms, which makes sense given the 
location of the outflow from earlier activity. As such, it looks 
like the most likely area for thunderstorm activity this afternoon
will be along and south of I-35. The front will clear the area by
around 00/01Z, taking storms with it.

A few gusty winds will be possible just behind the front with a 
tight pressure gradient in place. Surface ridging will commence 
following fropa, and winds will quickly relax by this evening. Drier 
air will move in tonight with dewpoints dropping into the upper 50s 
north of I-70 by sunrise Tuesday. With light winds, clearing skies 
and dewpoint depressions of only a few degrees, patchy fog will be 
possible by early tomorrow morning, especially in areas that 
received rainfall this morning and areas that receive rainfall 
this afternoon.

Higher pressure will continue to work into the area tomorrow with 
the center of the surface high located directly over central KS by 
Tuesday night. Temperatures will only warm to near 80 degrees under 
sunny skies, making for very enjoyable conditions tomorrow 
afternoon.

.LONG TERM...(Tuesday night through Monday)
Issued at 332 PM CDT Mon Aug 26 2019

High pressure will stay in control of our conditions through 
midweek before it begins to move southeast of the region on 
Thursday. Southerly winds on the back side of the surface ridge 
will begin to advect moister and warmer conditions into the CWA on
Thursday. The next chance for rain and storms appears to be late 
Thursday or early Friday when the next front is forecast to move 
into northeastern portions of Kansas. A more active pattern could 
persist into early next weekend so will monitor those trends 
through the week.

&&

.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1148 PM CDT Mon Aug 26 2019

Shallow fog will result in localized MVFR to IFR restrictions 
along and northeast of a line from OWI to MYZ, but confidence in 
duration and coverage is on the lower side with the fog fighting
high clouds and increasingly drier air. VFR conditions are 
forecast for Tuesday once the fog lifts in the morning with 
northwest winds of 5 to 10 kts.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Skow
SHORT TERM...Teefey
LONG TERM...Teefey
AVIATION...Skow