916
FXUS63 KSGF 181703
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
1203 PM CDT Tue Jun 18 2024

.KEY MESSAGES...

-  Breezy conditions today with southerly wind gusts up to 25-35
   mph, especially west of Highway 65.

-  15-30% chances for isolated to scattered showers and
   thunderstorms east of Highway 65 today and over west Missouri
   Wednesday.

-  Heat and humidity return late this week.

-  Signal for above normal temperatures to continue through the
   rest of June.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 400 AM CDT Tue Jun 18 2024

Current water vapor imagery depicts moisture venting out from a
tropical disturbance in the Gulf and spreading into the ridging
pattern across the east CONUS. The edge of this moisture is
barely reaching into our eastern counties as evidenced by a
smooth edge of high clouds. Meanwhile, a potent trough is
digging over the Rocky Mountains. Synoptic ascent and westerly
flow east of the Rockies is forcing strong lee surface
cyclogenesis across NE/SD. This is contributing to a sharp
surface pressure gradient that is reaching into our CWA.
Surface winds have been increasing as a result. Latest obs have
Springfield and Joplin gusting up to 20-25 mph at times.
Additionally, low-level moisture is quite abundant with some low
stratus developing within low dewpoint depressions in the
eastern Ozarks.


Breezy conditions today, especially west of Highway 65:

The aforementioned pressure gradient will continue to increase
southerly wind speeds today. By 8-10 AM, sustained winds will
increase to 15-20 mph. Gusts will reach into the 20-30 mph
range, with higher speeds toward the MO/KS border. NBM gives an
area north of I-44 and west of Hwy 65 a 40-60% chance of gusts
above 30 mph this afternoon, but only a 10% chance of gusts >35
mph. However, RAP and HRRR soundings seem to support a somewhat
greater chance of gusts above 35 mph with momentum transfers
capping out at 35 kts, especially out near Joplin. However,
wind advisory criteria will still likely not be met.


15-40% chances for isolated showers and thunderstorms today:

With the tropical moisture just clipping into our eastern CWA,
and positive vorticity advection on the western fringes of the
upper-level high still present, today will once again feature
15-40% chances for isolated showers and thunderstorms east of
Hwy 65, with the greatest chances across the eastern Ozarks.
Given the pattern observed yesterday of thin bands of light to
moderate precipitation with isolated embedded thunderstorms,
this will likely be the nature of the precipitation again this
afternoon. This is supported by SBCAPE values of <750 J/kg out
east, according to the HREF, likely due to the more
synoptically-forced cloud cover and light rain. Further west,
these bands would be much more isolated and cellular in nature--
if they are to form, that is. Currently, only the ARW and NSSL
models have light showers reaching the Hwy 65 corridor, while
the NAM Nest and HRRR do not depict this. Therefore, generally
only 10-15% chances exist for the Springfield area and locations
along the Hwy 65 corridor. If storms are to form, lightning
will be the main hazards with brief, heavy downpours being a
secondary hazard due to 1.75-2" PWATs.

With continued cloud cover over the eastern Ozarks, highs there
will be in the lower 80s while locations west of Hwy 65 and
north of I-44 will reach into the upper 80s. Lows will then
continue to be in the upper 60s to lower 70s.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 400 AM CDT Tue Jun 18 2024

15-20% chances for isolated showers and thunderstorms Wednesday:

A shortwave trough will eject off the Rockies into ND/MN/CA
during the day Wednesday. This will force a surface cold front
to sag through the central Plains. The jet stream will stay NW
of our area, so the cold front will not make it into our CWA.,
so highs will make it into the middle to upper 80s. However, the
cold front will provide lift for showers and thunderstorms
ahead of it. It should be said that our 15-20% chances in
extreme SE KS and west MO are more likely due to smoothing of
the greater chances out along the front in KS/north MO. So these
areas could see no precipitation, but there is a small chance
that some remnant showers and thunderstorms make it into the
area Wednesday afternoon.

Additionally, despite <15% chances elsewhere, CAMs do hint at
some isolated showers still possible across our CWA due to the
ongoing tropical disturbance. However, confidence in anything
breaking out is low as the upper-level high to the east will be
reaching its way into our region, meaning subsidence will likely
win out. Nevertheless, don`t be surprised if a random pop-up
shower and/or thunderstorm develops out of the 15% chance range
(along and east of Hwy 65). Then, lows will be in the upper 60s
Wednesday night.


Heat and humidity return late this week:

The upper-level high really starts taking on an elongated shape
starting Thursday, building and spreading westward into our
area. Increased subsidence and adiabatic warming from this high,
as well as somewhat clear skies and low chances for
precipitation, highs will begin to climb back into the 90s with
lows back into the 70s. The heat looks to peak on Saturday with
highs in the middle 90s and lows in the middle 70s.

A shortwave trough is then forecast to traverse the northern
states Sunday. An associated cold front is forecast to at make
it into parts of our CWA. This will bring chances for more
widespread showers and thunderstorms Sunday afternoon and
evening (15-30% as of now). WPC guidance--in agreement with
ensemble means and clusters--has the front stalling across
southern MO before quickly lifting back out as a warm front
Monday morning. This means relief will not last long. Highs
Sunday will still be in the upper 80s, then rise back into the
lower and middle 90s Monday and Tuesday. It will be important to
continue to practice heat safety the end of this week into the
beginning of next week as Heat Indices look to reach back into
the 95-100 F range (possibly higher).


Signal for above normal temperatures to continue through June:

The prolonged warmth does not look to end anytime soon with the
CPC continuing to advertise 50-60% chances for above normal
temperatures through the end of June. This is due to ensembles
and clusters continuing to signal a ridge to develop over the
central CONUS. Also during this period, there is a 30-40%
chance for above normal precipitation.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1135 AM CDT Tue Jun 18 2024

A cumulus field of mid-level clouds is currently advancing
northward. From 19z-01z, isolated showers and thunderstorms are
possible (15-20% chances) at BBG and SGF, although most
precipitation should stay east of Highway 65. After this time
period chances of showers diminish and mid-level cumulus clouds
give way to clearer skies. Thus, VFR condtions are expected to
persist through the TAF period. Gusty southerly winds of 15-25
knots will begin to diminish after 00z, reaching 5-10 knots by
very late tonight/early tomorrow morning as a surface pressure
gradient over Missouri weakens.

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
KS...None.
MO...None.

&&

$$

SHORT TERM...Price
LONG TERM...Price
AVIATION...Kenny