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Area Forecast Discussion
Issued by NWS Topeka, KS
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FXUS63 KTOP 240838
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
338 AM CDT Wed Apr 24 2024

.KEY MESSAGES...

- One final day of quiet weather today before storm chances increase
  late tonight into Thursday.

- Multiple rounds of severe weather are possible beginning
  Thursday morning. Highest chances for severe weather are on
  Friday afternoon/evening and again Saturday afternoon and
  evening.

&&

.DISCUSSION...
Issued at 337 AM CDT Wed Apr 24 2024

Weak northwesterly flow observed this morning, with the mid level
jet streaming from the western high plains into NE and KS this
morning. Weak isentropic ascent has resulted in elevated showers and
isolated thunder this morning across central Kansas. Cannot rule out
an isolated shower this afternoon over northeast Kansas, but given
the high cloud bases (around 12 kft), do not expect much of any
QPF today. Highs today are slightly cooler in the lower 70s
underneath light winds and high pressure in place.

As a southern stream upper trough enters the southwest CONUS
tonight, upstream height falls enter into the panhandles amidst
increasing southerly flow and warm advection across the state. CAMs
are consistent between current and previous runs of widespread
showers and thunderstorms developing after 12Z, spreading south
and east through northeast Kansas in the morning to early
afternoon periods. MUCAPE initially less than 500 J/KG wil
continue to improve in upwards of 1500 J/KG by the afternoon
while effective shear is favorable around 50 kts. While most of
the morning convection should not be severe, we may see isolated
stronger updrafts capable of hail to quarter size and damaging
wind gusts. With models signaling that the rain and low cloud
cover will linger through much of the day, opted to continue
lowering highs Thursday, down to the mid and upper 60s.
Confidence is low in additional convection impacting the CWA
Thursday evening, given the slower trend of the upper trough
axis and subsequent position of the dryline towards western
Kansas at 00Z Friday. If storms develop in this area in the
evening, there is a low possibility that they could impact
portions of north central Kansas overnight before dissipating
quickly as they enter a more stable environment towards eastern
Kansas.

By Friday afternoon, concern for more widespread severe weather
grows as the the dryline edges into eastern Kansas. Operational mid
term guidance is somewhat varied on the upper trough position
and track of the system as it lifts into southern NE and western
IA by 00Z Sat. There is a good signal for an EML throughout the
afternoon while sfc CAPE builds in upwards of 3000 J/KG. Models
however still struggle with initiation in the CWA as the better
height falls either occur earlier in the day or remain well to
our north, overall limiting severe potential. However, given the
forecast soundings and long, low level curvature on the
hodographs by 21Z...if storms are able to form, they will be
severe with all hazards possible, including tornadoes. These
storms shift off to the east later in the evening, bringing an
end to this round of convection. On another note, a wind
advisory will likely be needed Friday afternoon as NBM spread is
pretty small in the afternoon with south winds from 25 to 35
mph sustained, gusting to 50 mph.

On Saturday the next upper shortwave trough enters the region while
a sfc low quickly deepens over western CO, enhancing the warm, moist
advection into the CWA. Guidance is persistent in developing
widespread showers and thunderstorms in the afternoon and
evening. Minimal inhibition and SFC based CAPE in excess of 2000
J/KG suggest the possibility for embedded supercells to form.
Large hail, damaging wind gusts, and isolated tornadoes remain
on the table for potential hazards with the strongest updrafts.
It`s also important to note that locally heavy rainfall cannot
be ruled out given the deep moisture within the atmospheric
column and PWATs up to 1.6 inches. Any localized flooding
however will be dependent upon the amount of rainfall that we
receive Thursday and Friday. The system quickly exits the area
by Sunday as upper ridge builds east, bringing quieter
conditions next week. Temperatures remain mild or slightly above
average in the low 80s while overnight lows are mostly in the
50s.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1218 AM CDT Wed Apr 24 2024

VFR at terminals as high clouds are expected to increase
overnight, accompanied by a 12-15 kft mid level cloud deck
developing aft 14Z. Light north winds gradually veer to the east
below 10 kts through the period. As next system arrives, may
see a <10 kft stratus deck lift northeastward at the end of
forecast period.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Prieto
AVIATION...Prieto
National Weather Service Regional Headquarters
