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000
FXUS63 KDVN 201050
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
550 AM CDT Sat Apr 20 2024

.KEY MESSAGES...

- A freeze warning is in effect for this morning. Cold night
  time temperatures will continue through the weekend leading to
  additional frost/freeze advisories/warnings.

- Some sprinkles are possible later today, especially north of
  I-80.

- Active pattern into next week will bring additional rounds of
  rain and thunderstorms Monday night into Tuesday and into next
  weekend.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 313 AM CDT Sat Apr 20 2024

Upper level low over the Great Lakes will move east through the
day. A shortwave rotating around this low will move into the
northern CWA later this afternoon. With cold air aloft, low
level lapse rates will increase this afternoon as the sfc is
warmed by the sun. This paired with the shortwave will lead to
cloud development. For most of us, this will be clouds with
breaks of sun. North of I-80 there is a low chance (less than
15%) that some showers could form. The HRRR has consistently had
a signal for showers this afternoon. Model Z suggests some
robust showers. With dry sub-cloud levels, think this will
mainly fall as virga. As such have added 14% pops and sprinkles
to the forecast. If the model Z is correct, we could even see
some graupel mixed into these showers, especially further north.
These showers and the virga could lead to some localized wind
gusts of 30 mph or more. Will leave this out of the HWO at this
time with lower confidence in occurrence. Highs today should
struggle to reach 50 across most of the area, with the winds it
will feel rather chilly.

Tonight, the clouds should clear and the coldest air of this
cold snap is in place. Widespread frost and near or below
freezing temperatures are expected. Additional frost/freeze
products will be needed tonight. Lows in the upper 20s to low
30s are expected.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 313 AM CDT Sat Apr 20 2024

More of the same to start the long term with cooler temperatures
expected the rest of the weekend. Weak ridging will build into
the area on Sunday and Monday ahead of a clipper Monday night
into Tuesday. The clipper is expected to pull through the area
Tuesday as NW flow takes over. This will keep us in the 60s,
before ridging builds in ahead of deep trof that is forecast to
build into the western CONUS to end the week.

Temperatures on Sunday will be warmer than today we see near 60
degree temps everywhere. Lows Sunday into Monday may result in
another frost/freeze advisory/warning for portions of the CWA.
Going into Monday, a brief surge of warm advection will combine
with another progressive upper low arriving from southerly
Canada to bring a chance for showers and a few thunderstorms.
Overall totals look to be light as most of the area will see
under a quarter inch of rain from this system.

After this, we see a cooler Wednesday before we start warming up
across the area. Another system is expected this weekend,
however there remains timing differences between the guidance so
confidence in a specific solution is low.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 546 AM CDT Sat Apr 20 2024

VFR conditions are expected at all TAF sites as a VFR deck moves
into the area from the north in the next couple of hours. There
are some indications that CID and DBQ could see some MVFR cigs,
so have added few025. I think heating today will make those
heights rise before they get here, but not completely convinced,
hence the few025. Otherwise, winds will again be gusty this
afternoon across the area as well. After the sun sets, expect
the clouds to break and winds to slacken also.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Freeze Warning until 8 AM CDT this morning for IAZ040>042-
     051>054-063>068-076>078-087-088-098.
IL...Freeze Warning until 8 AM CDT this morning for ILZ001-002-007-
     009-015>018-024.
MO...None.

&&

$$

SHORT TERM...Gibbs
LONG TERM...Gibbs
AVIATION...Gibbs