Old Jamestown, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

899
FXUS63 KLSX 221057
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
457 AM CST Sun Feb 22 2026

.KEY MESSAGES...

- Dry, abnormally-cool conditions last through Monday before a
  mid-week warmup.

- A quick-moving system brings a 30-60% chance for rain Thursday,
  though no adverse impacts are expected.


&&

.SHORT TERM...  (Through Late Monday Afternoon)
Issued at 220 AM CST Sun Feb 22 2026

Much of the Great Lakes and Mississippi Valley regions remain under
the influence of a strong surface low centered over southern
Ontario, with a strong pressure gradient forcing 15-20mph sustained
northwesterly winds over much of the bi-state region at this hour.
The northwesterly wind is also promoting dry, cool air at the
surface that will continue on through today and keep highs up to 20
degrees below normal for late February. Gusty winds up to 30mph will
continue across most of the region today, which coupled with minimum
RH values of 25-35% for most will result in sporadic elevated fire
danger across the region. That said, the cooler air that continues
to advect southward may hold RH values in check and preclude a more
tangible fire weather threat. Regardless, any plans to burn today
should be carried out with caution given antecedent dry conditions.

We get no reprieve from the gusty winds overnight with the strong
cyclone making no meaningful eastward progress. The persistent cold
air advection will likely send tonight`s lows into the teens for
most of the region and single digits in northeast Missouri. Wind
chill values are almost guaranteed to be in the single digits
areawide, with subzero values in northeast Missouri. One more chilly
day is in store for the start of the work week, though winds will
slacken through the day from west to east as the strong cyclone
finally moves downstream and surface ridging takes hold. Similar
concerns for an elevated fire danger will exist Monday, though even
less confidence exists in sufficient dry and windy conditions being
present in any one place outside of sporadic instances.

MRB

&&

.LONG TERM...  (Monday Night through Saturday)
Issued at 220 AM CST Sun Feb 22 2026

A northern stream clipper across south-central Canada helps shunt
our surface ridge east as quickly as it arrives, and by Tuesday
morning we are squarely in warm, southerly return flow. Winds will
strengthen as the surface pressure gradient ahead of the clipper
tightens, bolstering warm air advection that sends temperatures into
the mid-40s to upper 50s. This pattern is typically conducive of an
elevated fire danger, and while some uncertainty does exist on how
dry we will get, that threat is becoming more tangible Tuesday
afternoon. The front arrives Tuesday night, though exactly how that
front impacts temperatures is somewhat unclear. While some guidance
does suggest modest cold advection lowering temperatures a bit on
Wednesday, most depict the cold air locked closer to the low itself
in the Great Lakes. As such, I expect Wednesday to be as warm as
Tuesday if not a hair warmer.

Guidance continues to show a very progressive wave aloft diving from
the Pacific Northwest into the Mid-Mississippi Valley Wednesday
night into Thursday. Nearly all of the available guidance shows
deeper cyclogenesis occurring as the system is departing the region,
which will keep the system quick-moving and fairly unimpactful.
While most of us will likely (60-80%) see some rain sometime
Thursday, there`s only a 30-50% chance of 0.25 inches or more east
of the Mississippi River. Even if we get twice as much rain as that,
it would be nothing but beneficial for the drought-ridden bi-state
region. The progressive pattern lasts into Friday, with temperatures
likely (80% chance) quickly jumping into the 60s across most of the
region behind this system.

Guidance diverges notably from Saturday onward with a strong cold
front diving south from the Upper Midwest. The timing of the front
will have large implications on precipitation chances and
temperatures Saturday. A slower front will keep temperatures quite
warm to end February. From then on, the boundary stalls somewhere in
the broader region. While NBM IQRs for high temperatures are
consistently 20-30 degrees Sunday onward, indicating very high
uncertainty, the entire distribution cools by 20 degrees and calls
for a seasonably-cool start to March.

MRB

&&

.AVIATION...  (For the 12z TAFs through 12z Monday Morning)
Issued at 449 AM CST Sun Feb 22 2026


Dry weather is expected through the period. There will be some low
clouds initially affecting UIN with ceilings between 1500-2500
feet, but they are expected to move out of that terminal by mid
morning (15-16Z). Otherwise, VFR conditions are expected with
northwesterly winds (300-330 degrees) through the period with
gusts between 20 and 30 knots.

Britt

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

$$

WFO LSX