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Area Forecast Discussion (AFD)

Issued by Topeka, KS (TOP)

FXUS63 KTOP 192016

Area Forecast Discussion
National Weather Service Topeka KS
316 PM CDT Fri Jul 19 2019

.SHORT TERM...(This evening through Saturday)
Issued at 314 PM CDT Fri Jul 19 2019

Sfc low lingers over eastern Colorado this afternoon with gusty 
southerly flow between from 15 to 20 mph at the surface. 
Gusts up to 25 mph will continue through peak heating before
waning to near 10 mph sustained overnight. Heat indices this 
afternoon are once again maxing out in the 108 to 115 degree 
range. Moisture advection over far eastern areas of the CWA 
continues to edge dewpoints into the middle 70s while temps hover
in the upper 90s.

The Excessive Heat Warning continues for one final afternoon 
tomorrow with heat indices reaching between 108 to 114 degrees. 
Approaching mid and high clouds from the northwest may lower temps
by a few degrees in north central Kansas, but noticeable impacts 
are minimal. Forecast soundings are consistent in the capping 
inversion weakening by late afternoon with most guidance centering
the boundary from northwest Kansas through south central 
Nebraska. I cannot rule out a slight chance for a few isolated 
thunderstorms developing in this area, impacting far north central
Kansas during the late afternoon. Upper forcing is displaced from
the front until later evening so confidence remains low at this 
point. Main hazards would be damaging winds and locally heavy 

.LONG TERM...(Saturday night through Friday)
Issued at 314 PM CDT Fri Jul 19 2019

Main focus in the extended period is the cold front and
associated precipitation Saturday night through Sunday evening. 
Latest model trends are slowing on the progression of the front, 
residing it closer to the Nebraska and Kansas border by Sunday 
12Z. Have still kept a slight chance mention as far south as the 
Interstate 70 corridor overnight, but have increased chances to 
likely near the highway 36 corridor. Given effective bulk shear 
values up to 35 kts by Sunday morning, strong wind gusts, locally 
heavy rainfall and small hail would be the main hazards with the 
strongest storms. 

Uncertainty remains on how precip evolves and/or redevelops during 
the late afternoon and evening Sunday as a stronger organized 
upper trough enters Nebraska by 00Z Monday. Kept a low chance 
mention for thunderstorms in the afternoon based on the outlier 
NAM, but otherwise overall consensus is for a cluster of showers 
and thunderstorms to develop along and behind the front, tracking 
through the CWA overnight. While surface based storms are possible
along the boundary, weak effective shear should limit the severe 
storm coverage with most of the activity being elevated. Heavy 
rainfall, strong wind gusts and hail are all possible throughout 
the evening. Rainfall amounts up to 1 inch, locally higher, are 
possible through Monday morning.

Cooler air behind the front arrives on Monday with much needed
relief in the form of dewpoints in the upper 50s with highs in 
the low 80s. As the sfc ridge passes overhead Tuesday morning, 
lows could fall into the upper 50s. Dry, northwesterly flow aloft 
continues through Thursday with seasonably cool temps in the 80s 
throughout. Ridge begins to build back east on Friday with low 90s
returning to the area. 


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1213 PM CDT Fri Jul 19 2019

Upper ridge remains in control of the region with VFR conditions
prevailing at KTOP/KFOE/KMHK. LLWS once again develops aft 04Z 
with the low level jet peaking near 45 kts at 1500 feet.


Excessive Heat Warning until 8 PM CDT Saturday for KSZ008>012-



LONG TERM...Prieto