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Area Forecast Discussion (AFD)

Issued by Topeka, KS (TOP)

FXUS63 KTOP 170845

Area Forecast Discussion
National Weather Service Topeka KS
345 AM CDT Wed Jul 17 2019

.SHORT TERM...(Today and tonight)
Issued at 345 AM CDT Wed Jul 17 2019

Shortwave ridge axis was pushing east over the central Plains early 
this morning with veering lower and middle tropospheric flow 
leading to weak to moderate warm air advection. Enough mid-level 
moisture was in place (700 mb dewpoints around 7 C) to produce 
isolated convection across central and eastern portions of Kansas 
early this morning, with many observation sites reporting mid cloud 
well away from the convection. Recent RAP (and to a lesser extent 
HRRR) runs suggesting an uptick in coverage over the next few-
several hours and will keep a small PoP for the entire area into the 
mid-morning. 850 mb temps remain on track to rise 3-4 C from Tuesday 
afternoon with surface dewpoints able to remain in the mid 60s to 
mid 70s in a moist boundary layer. A moderate pressure gradient over 
the region east of a deepening lee trough and weak cold front should 
be adequate to promote sufficient mixing despite any lingering 
convection to bring afternoon temps in the mid 90s to around 100 and 
apparent temps into the 105 to 110 range. Have kept some mention of 
thunderstorms in portions of north central Kansas where convection 
off the stalling front may approach though drier antecedent 
conditions compared to this morning should limit this progression.

.LONG TERM...(Thursday through Tuesday)
Issued at 345 AM CDT Wed Jul 17 2019

The persistent high levels of heat and humidity remain to be the 
main concern with little opportunity for significant changes to 
conditions until late in the weekend as a broad upper ridge lingers 
over the southern states. Heat index values should continue to peak 
in the 103 to 112 range with a moderate low-level jet keeping 
overnight temps in the mid 70s to around 80. A pattern change takes 
place during the weekend and allows for the passage of a cold front 
around Sunday. There should be at least a small opportunity for 
convection associated with the front as well though have limited 
mention to nighttime periods given the very warm low levels keeping 
some capping in place. Temps early next week should return to near 
normal values. 


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1141 PM CDT Tue Jul 16 2019

Convection chances still looking low overnight. A 925mb jet over 
central and north-central KS in addition to some low level WAA
could provide some lifting, but thinking that will most likely 
not be enough to overcome the warm layer. LLWS associated with 
the aforementioned jet could impact the KMHK terminal from 09Z 
through around 12Z with southerly winds around 35 kts at 1500 ft 
AGL. Later in the period, southerly surface winds will increase 
and become gusty by mid-morning Wed. 


Excessive Heat Warning from 1 PM this afternoon to 8 PM CDT 
Saturday for KSZ008>012-020>024-026-034>040-054>056-058-059.