Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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000
FXUS63 KEAX 290545
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1245 AM CDT Fri Mar 29 2024

.KEY MESSAGES...

- Warm and breezy conditions are forecast for Friday.

- There is a 15 to 30 percent chance of showers and
  thunderstorms Friday evening and night mainly southeast of
  I-35 as a cold front moves through the region. A rogue strong
  to severe storm is possible, but widespread severe weather is
  not expected.

- Multiple rounds of showers and storms are forecast Sunday and
  Monday, with severe weather possible, particularly on Monday.

- Cooler and drier weather returns for the middle of next week.

&&

.DISCUSSION...
Issued at 209 PM CDT Thu Mar 28 2024

Objective 12z analysis indicates a deep upper-level trough in
the Ohio Valley and Midwest, with upstream ridging in the
Rockies and Great Plains. Another trough was moving into the
Pacific Northwest. Low- and mid-level warm advection was present
in the Plains, underneath the progressive central U.S. ridge.
Surface temperatures across the Plains have responded
accordingly, with widespread 60s and breezy southwest winds
across the region.

A weak perturbation will eject in advance of the Pacific
Northwest trough tonight and tomorrow into the northern Plains,
leading to the development/progression of a surface low in the
central Plains and elevated southerly flow to its south and
southeast. Model soundings indicate sufficient mixing during the
midday and afternoon hours to generate gusts of 30 to 40 mph in
much of the area, with stronger gusts possible in far southern
portions of the CWA. Have hoisted a wind advisory for Linn
County KS and Bates County MO as a result, in coordination with
TOP/SGF/ICT. Surface temperatures will continue to warm, with
70s forecast across the region.

Moisture return will also commence with the developing low,
leading to a sharp rise in dew points tonight into tomorrow.
Despite steady mixing on Friday, dew point rises of 10 to 15
degrees are forecast during this period. As the system`s cold
front approaches the region on Friday evening, sufficient lift,
moisture, and instability may be present for isolated to
scattered showers and thunderstorms (up to 30 percent chance) to
develop along and in advance of the front. The highest chances
(as depicted in convection-allowing model (CAM) guidance)
appear to be in north-central and central Missouri, in closer
proximity to the stronger large-scale ascent and in a region of
somewhat richer boundary-layer moisture. However, CAMs are not
particularly aggressive in developing convection and certainly
not in a widespread manner, owing to sufficient capping in the
warm sector. That said, examination of HREF model soundings
would suggest an environment not completely prohibitive of
severe weather, with MLCAPE up to 500 J/kg and deep-layer bulk
shear exceeding 40 kt. Thus, if models trend toward weaker
inhibition, will need to watch potential for a strong/severe
storm or two. A more likely outcome: elevated storms develop as
the low-level jet nocturnally intensifies, with timing favoring
the aforementioned northeastern portions of the CWA.

With cold-frontal passage Friday night, temperatures will be
cooler on Saturday (by about 7-12 degrees)...but still above
seasonal averages...with dry conditions. However, a stronger
system will begin to affect the region by Saturday night. Though
the large-scale trough will be near the Pacific Coast, a large
region of downstream southwesterly midlevel flow will prevail,
and multiple perturbations will be ejecting from the deeper
trough. Surface cyclogenesis will commence in the lee of the
Rockies by Saturday night, with a developing baroclinic zone
extending eastward into the Ohio Valley. Positioning of this
baroclinic zone will be critical to (1) high temperatures on
Sunday (which could range from upper 50s to low 80s across the
CWA), (2) the axis of highest severe-weather risk on Sunday
afternoon/night (likely in close proximity to stronger lift near
the warm front and from low-level jet contributions), and (3)
geographic placement of subsequent severe-weather risk on Monday
(with a farther north positioning of the warm front leading to
a more widespread risk for the CWA).

Ensemble probabilities of sufficient CAPE-shear parameter space
(exceeding 50 percent Sunday night through Monday afternoon)
would suggest severe weather is a concern during this period,
but uncertainty in frontal placement and timing of the vorticity
maxima ejecting from the large-scale trough leads to fairly low
confidence on the most favorable time window and geographic
placement of the highest risk. Ensemble spread is quite high
with the low`s position and progression through the central
U.S., for example. Consider the 12z CMC`s low position near the
northeast MO/northwest IL/southeast IA intersection at 00z
Tuesday, and the 12z GFS`s just north of Topeka, KS.

On the other hand, confidence is reasonably high that widespread
precipitation will occur in the region during the Sunday-Monday
time period (and not that whole period). Continue to monitor
forecasts through the weekend to keep updated with the latest
forecast thinking. After passage of this system, the rest of the
week looks drier with a quick cooldown Tuesday and Wednesday
followed by a rapid warm-up later in the week.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1240 AM CDT Fri Mar 29 2024

Stronger winds above the surface will mox to the surface shortly
after sunrise leading to gusty winds today. Scattered- broken
deck at 3-4K ft agl is expected to develop, potentially leading
to a few showers/thunderstorms after 00Z Saturday if the cap can
be overcome. Bes chance for thunderstorms will be east of TAF
sites across northern into central Missouri.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Wind Advisory from 10 AM this morning to 7 PM CDT this evening
     for MOZ053.
KS...Wind Advisory from 10 AM this morning to 7 PM CDT this evening
     for KSZ060.

&&

$$

DISCUSSION...CMS
AVIATION...BT


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