Hidden Valley

000
FXUS63 KEAX 151724
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1224 PM CDT Tue Sep 15 2026

.KEY MESSAGES...

- Multiple rounds of rainfall anticipated across NE KS and NW MO 
starting this morning and continuing through Wednesday morning. 
Heavy downpours are expected which may lead to flash flooding. A 
Flood Watch is in effect for NW MO and NE KS (including the KC 
metro) from 1PM Tuesday through 1PM Wednesday.

- Runoff is expected to flow into creeks and streams resulting in 
elevated river levels and accelerated flow. Poor drainage and urban 
areas may also see some flooding.

- Wide range of temperatures anticipated NW MO and NE KS around
  80 and central MO in the mid 90s. There is the potential for
  some hazardous heat across central and southern MO today and
  tomorrow as heat index values approach 100F-105F.

&&

.DISCUSSION...
Issued at 321 AM CDT Tue Sep 15 2026

The short term pattern continues to be dominated by turbulent upper 
level SW flow aloft and a slow moving surface trough across eastern 
CO and western KS. This results in a stationary boundary which 
extends along the KS/NE border eastward along the MO/IA border. CAM 
guidance shows a broad LLJ extending across the south central Plains 
toward the Great Lakes. Downward mixing across the lower level warm 
sector is creating an area of surface convergence along the 
previously mentioned boundary similar to an exit region of a low 
level jet. This also boost warm air advection just enough to keep 
some residual surface instability just enough to maintain convective 
development across the area.

Cool outflow from storms earlier Monday evening into early Tuesday 
morning have stabilized the low levels just enough to gives us a 
short break in the precipitable action through the overnight. 
However, the low level warm air and moisture advection feeding 
directly from the moisture rich Ozarks will be able to replenish the 
environment consumed by the previous round of storms. The wild card 
in this is will there be enough forcing and instability to initiate 
further rounds of precipitation through the overnight (unlikely) or 
how will a larger scale cold front from the NW affect convective 
initiation. We will focus on the synoptic scale front as it will be 
much more influential. Current CAM guidance times this front 
approaching far NW MO/NE KS as sunrise approaches.

Daytime heating is expected to accelerate destabilization as warm 
air and moisture continue to build northward. Looking vertically the 
cold front exhibits a shallow slant backwards such that at 850mb the 
front remains in SE NE/SW IA. This creates a wide area of 
precipitable development that is expected to envelope much of NW MO 
and NE KS as the frontal system slowly moves across the region 
through the day today. Multiple upper level shortwaves combined with 
moisture convergence and lift across the frontal boundary as well as 
steady WAA ahead of the boundary keeps convection ongoing through 
much of the day. Guidance favors showers to be mostly elevated 
behind the surface front, but ahead of the upper level frontal 
features. This combined with limited shear and helicity generally 
constrain strong to severe potential; however, the transport of 
moisture upward combined with climatically high PWATs (>= 2 inches 
across NW MO) yield possibility for training storms with repeated 
heavy downpours. QPF of 2-3 inches is anticipated across NW MO with 
locally higher amounts possible. This brings about chances for river 
and flash flooding across much of northern MO and NE KS as flash 
flood guidance sits at 1.5 to 2 inches of rainfall per hour and 3 
hours respectively. A Flood Watch remains active until Wednesday 
afternoon across areas where the greatest probabilities for flooding 
impacts are forecasted. This Flood Watch was expanded to cover the 
KC metro as storms look to train over the region Tuesday evening 
into Wednesday morning. HREF guidance 25-50 percent chances of 
exceeding 2 inches of accumulated rainfall with isolated 20-40 
percent chances of exceeding 3 inches of rainfall. Deterministic 
guidance has been all over the board with QPF, but given the 
potential for training storms with heavy downpours, it felt prudent 
to extend the watch southward. CAM guidance does present a 
small window Tuesday evening where there is the opportunity for 
some isolated strong to severe storms as the synoptic cold front
meets up with a weak boundary from the surface low to the west.
If a storm is able to become surface based ahead of the surface
cold front, there is a chance to get some isolated severe gusts
out of some storms. Increased localized shear as the boundaries
meet could also bring the potential from some hail or tornado, 
but chances remain minimal. Heavy rainfall remains the primary 
hazard.

Rain continues to linger across the area through Tuesday night into 
Wednesday morning. Looking at temperatures, rain cools down 
temperatures into 70s and 80s across NW MO and NE KS with upper 90s 
expected across central MO today. This trend continues into 
Wednesday where a narrow area of hazardous heat is possible across 
Cooper county and points south and west with heat index values 
approaching 100-105F. The extended pattern remains fairly active 
with the area remaining in the periphery of a synoptic scale high 
and a lower level lee trough. This also looks to lift highs back 
toward the 90s as the end of the week approaches before a 
substantial wave moves through the area this weekend bringing 
additional precipitation chances. Additional digging trough keep 
storm chances around through Monday evening before ridging dries us 
off early to mid next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1224 PM CDT Tue Sep 15 2026

VFR conds will prevail thru 23Z-00Z when mod tsra will move into
the into the terminals. Storms are expected to cont at the TAF
sites thru 13Z-15Z with reduced vis to 3-5SM. Cigs will remain 
VFR thru 00Z when bkn cigs around 4kft are fcst (except STJ
which will become MVFR aft 23Z). We will then see a gradual 
lowering of cigs thru the evening with cigs dropping into MVFR 
around 03Z-05Z and into IFR btn 06Z-08Z. Winds to begin the TAF 
pd will be out of the W around 10kts (except STJ which will
begin he TAF northerly) becmg northerly around 10kts aft 00Z. 
By 03Z-05Z winds will shift to the east while remaining around 
10kts.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through Wednesday afternoon for MOZ001>006-011>015-
     020>022-028-029-037.
KS...Flood Watch through Wednesday afternoon for KSZ025-102>105.

&&

$$

DISCUSSION...Pesel
AVIATION...73