261
FXUS63 KSGF 030830
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
330 AM CDT Thu Jul 3 2025

.KEY MESSAGES...

- Slightly above normal temperatures and moisture expected this
  holiday weekend with highs in the upper 80s to lower 90s and
  Heat Index values between 90 and 100.

- Isolated shower and thunderstorm chances (15-30%) west of
  Highway 65 for Friday (Independence Day) into Saturday.

- Additional 30-50% rain chances then exist region-wide Sunday
  through the middle of next week.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 330 AM CDT Thu Jul 3 2025

The overall synoptic pattern has not changed much over the last
24 hours. Water vapor imagery still depicts troughing over the
Great Lakes and Northeast CONUS, broad ridging slowly inching
eastward into the Plains states, and a shortwave across the
Desert Southwest. At the surface, a diffuse cold front is still
draped across the Appalachian Mountains into the southern Gulf
states, with surface high pressure still centered over the
Ozarks, bringing clear skies, calm winds, and cooler
temperatures in the lower to middle 60s this morning. Cooler
temperatures in the river valleys may promote some light patchy
fog/mist development. Indeed, some light fog is already starting
to show up in these valley areas on the GOES-19 Night Fog
imagery.


Slightly above normal Heat Index values between 90 and 100:

Weak southerly winds will return today as the surface high
departs eastward. This will slowly advect in warmer and more
moist air into the region from the south. High temperatures are
expected to reach near normal for early July, ranging from 88 to
90 F. Moisture will also increase, especially along the MO/KS
border, closer to the tighter Plains height gradient. Dewpoints
will reach into the middle to upper 60s. The combo of warmer
temperatures and higher dewpoints will raise Heat Index values
into the lower to middle 90s today. Temperatures and moisture
will slightly increase for Independence Day with highs ranging
from 89 to 91 and dewpoints in the upper 60s to lower 70s
yielding Heat Index values in the middle 90s, with localized
areas nearing 100. While this is only just above normal heat
for early July, extended periods spent outside can still produce
heat-related impacts. Make sure to be mindful of these signs
during the holiday weekend! Be proactive and mitigate any
effects by staying hydrated and taking frequent breaks in
cooler air (shade and buildings). As we head into the evening
of Independence Day, temperatures should decrease to the upper
70s.

There is a low-end (<15%) chance for a stray shower or
thunderstorm in extreme southwest MO and extreme southeast KS
along 700 mb frontogenesis collocated with a moisture gradient
pushing northeast. Confidence is overall low, though, for the
same reasons discussed in the next paragraph.


15-30% rain chances along and west of Hwy 65 for Independence Day:

Short-term model guidance suggest the aforementioned moisture
gradient and weak mid-level convergence will push into southwest
and central Missouri Friday. This lift within greater moisture
and sufficient instability could produce a few isolated showers
and thunderstorms alog and west of Highway 65 during the
afternoon/evening hours of Independence Day. This is low
confidence, though (only a 15-30% chance as of now), as
forecast soundings depict a very stout warm nose at around 600
mb with weak lapse rates above it. Additionally, our placement
within the synoptic pattern downstream of the ridge and within
negative vorticity is conducive for subsidence, which may squash
any development. However, HREF and SREF paintballs and QPF
footprints suggest some showers may still be possible. Be on the
lookout for any short-term updates on this potential.


&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 330 AM CDT Thu Jul 3 2025

Slightly above normal Heat Index values continue this weekend:

The ridge axis will begin elongating eastward and squashing
southward starting Saturday. Despite this, the axis will still
be centered over southern Missouri, keeping slightly above
normal temperatures and humidity in the area. Highs will remain
in the upper 80s and lower 90s with Heat Index values in the 90
to 100 range.


Rain chances increase to 30-50% by Sunday and into mid next week:

The ridge will have broken down by Sunday afternoon as mid- and
upper-level zonal flow takes hold just to our north.
Deterministic global models depict a ftrain of shortwaves
progressing through the zonal flow. Some waves and vorticity
maxima are stronger than others, which leads to slight timing
and intensity differences in global models. Therefore, daily
30-50% rain chances exist Sunday through Thursday due to these
differences. As of now, the best chances are Sunday and Monday
as we get closer to those days and model agreement increases,
however, there is an ensemble cluster signal for a more distinct
shortwave with more northwest flow evolving sometime in the
Tuesday to Thursday timeframe. The WPC is picking up on this
signal, outlining much of the state of Missouri in a risk for
heavy rainfall Wednesday.

Of additional note, GEFS and ECMWF AI mode guidance continue to
highlight a low-end (5%) chance that some of these storm
chances may bring a severe risk. This potential largely seems
low as LREF suggests <20 kts of deep layer shear through
Tuesday. However, along with the signal for a more distinct
shortwave, chances for shear >20 kts increase to 20-50% chance
for next Wednesday and Thursday. Trends will continue to be
monitored as we move forward.


Small temperature variations next week, but generally near normal:

With the variations in mid-level waves and chances for
precipitation, temperatures will have slight changes through
next week, but generally they will stay near normal in the
middle to upper 80s with lows around 70 F.



&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1240 AM CDT Thu Jul 3 2025

VFR conditions to prevail for the entire TAF period with 3-8 kt
south-southwesterly winds and a 5 kft cu field developing
between 16-01Z.

River valley fog is expected between 07-13Z, which should not
impact the TAF sites (>70% chance). BBG may see some reduced
visibilities from the surrounding valley fog/mist, but
confidence is too low to include in TAFs at the moment.

&&

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

&&

$$

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