525
FXUS63 KDVN 042334
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
634 PM CDT Sat May 4 2024

.KEY MESSAGES...

- Upper level pattern remains active, with periodic chances for
  showers and storms through next week.

- A potent dynamic system arriving Monday night to Tuesday could
  bring a more significant severe threat.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 145 PM CDT Sat May 4 2024

This Afternoon and Evening

A cold front currently located from near Decorah, Iowa to
Kirksville, MO will steadily progress eastward through the
outlook area this afternoon and evening, serving as the focus
for scattered storm development. Low-level moisture advection
via southerly flow has pushed dewpoints into the low/mid 60s
ahead of the front, and locations along and east of the
Mississippi River have had periods of filtered sun with temps
warming into the mid/upper 70s.

Trends with latest CAMs has been for a little lower coverage of
storms this afternoon and early evening, so have lowered rain
chances a bit. The best chances (40-70%) for storms are
expected in counties along/east of the Mississippi River between
3 - 6 PM. Overall the environmental setup (500-1500 J/kg MLCAPE
and ~30 kts deep layer shear) looks supportive of a few strong
to severe storms with the weaker shear as a limiting factor.
The strongest cells that pop up could produce wind gusts of 50
to 60 mph and hail up to quarter size, with this likely to
occur on an isolated basis.

Tonight and Sunday

A drier and much cooler post-frontal air mass ushers in tonight
with forecast lows in the upper 30s NW to upper 40s east/southeast.
Sunday will be very nice with highs in the upper 60s to low 70s
and fairly light winds through the day.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Issued at 145 PM CDT Sat May 4 2024

A broad, energetic pattern is set to begin spreading WAA rain
and thunder into the area as soon as Monday, with widespread
showers and thunderstorms expected Monday night into Tuesday.

This Monday night into Tuesday period continues to be shown as a
large/synoptic, strongly forced system, and there`s been a
consistent signal for a very strong jet streak within the
Midwest. Those broad scale factors continue to give an
indication that this may be a widespread severe weather
producer, and our CWA may be included in that. SPC has a Day 4
Slight Risk for severe weather encompassing the entire outlook
area. Latest CSU ML probabilities for severe weather also
highlight the local forecast area, with the max values to our
southeast over central to southern Illinois into Indiana.

A warm and breezy pattern is in store on the east side of this
broad potent trof next week. Highs in the 70s to lower 80s are
expected through Wednesday. Following that, the upper trof is
set to deepen, and place the warm air well south of the upper
Midwest, resulting a cooler, cloudier forecast in the 60s to
lower 70s to end the week. This could bring additional showers
and possibly thunder to the region as well, given the cold air
aloft and time of year over moist soil. The QPF in this period
should not be overly heavy, given no connection to the Gulf of
Mexico, but spotty rains over 0.50 appear possible in the
frequent shower chances to end the week.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 634 PM CDT Sat May 4 2024

Gusty northwest winds and a mix of MVFR to low-end VFR ceilings
will linger into the evening hours in the wake of a cold front
that is now draped over central Illinois. Eventually, the winds
will weaken by later tonight and the clouds will diminish,
leading to SKC across the area. MVFR fog remains possible at
CID late tonight, although a few models aren`t depicting any to
develop, so confidence in MVFR fog is around 50 to 70%, which
is still high enough to include in the CID TAF. High pressure
will gradually move in tonight through Sunday, which will turn
winds more easterly during the daylight hours Sunday.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.

&&

$$

SHORT TERM...Uttech
LONG TERM...Ervin
AVIATION...Schultz