Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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000
FXUS63 KDVN 191803
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
103 PM CDT Mon Jun 19 2017

.UPDATE...
Issued at 103 PM CDT Mon Jun 19 2017

The strongest shortwave in the cyclonic nw flow aloft was
producing a thunderstorm cluster in south central WI at midday.
Further upstream, a weaker feature evident on satellite water
vapor was producing a thunderstorm over south central MN, moving
southeast. This feature will likely spread a few showers and
thunderstorms into the Dubuque vicinity around mid afternoon.
Elsewhere, satellite and radar showed isolated showers popping up
in central IA, aligned along a similar axis with the downstream
weak showers/sprinkles exiting into central IL.

CAMS continue to suggest further development of the these upstream
features as they advance into the forecast area around mid
afternoon. MUCAPES were above 1000 J/KG at midday with advancing
steeper mid level lapse rates moving in during peak heating along with
seasonably low freezing levels. For now, coverage looks limited
and will be capped off at isolated to widely scattered or 20 to
30 pops. Cannot rule out storms these storms at least briefly
pulsing to produce small hail and strong gusty winds, but not
likely to reach severe limits given the wind profiles and meager
moisture.

&&

.SYNOPSIS...
Issued at 330 AM CDT Mon Jun 19 2017

Northwest flow aloft with embedded short waves with the strongest
shown on water vapor in ND moving southeast. Isolated thunderstorms
were located in eastern ND with this wave.

&&

.SHORT TERM...(Today and Tonight)
ISSUED AT 330 AM CDT Mon Jun 19 2017

Scattered thunderstorms mainly this afternoon.

Today: Decent short wave in ND will dive southeast and is expected
to trigger scattered thunderstorms this afternoon, mainly in our
northern and central counties. Forecast soundings indicate
MUCAPES of around 1500 J/KG, shear to 30 knots and freezing levels
around 9k ft. HIRES models suggest a band/cluster of thunderstorms
later this afternoon diving southeast into our nw cwa and then
tracking to about I-80 towards evening. This would be coming
through during peak heating and there is the potential for gusty
winds and hail up to nickel size. I will maintain pops in the
30-40 percent range (scattered coverage). Maximum temperatures
should range from the mid 70s along Highway 20 to the lower 80s in
extreme northeast MO.

Tonight: The wave will push off to our east by early evening and
will have a dry forecast as of now. However, if the HRRR is
correct a band of thunderstorms may keep pushing into our se cwa
early in the evening and pops may need to be added. Lows will
bottom out in the mid to upper 50s.

.LONG TERM...(Tuesday through Sunday)
ISSUED AT 330 AM CDT Mon Jun 19 2017

Periods of warmer temps and potential for several rounds of showers
and thunderstorms are the highlights of the long term period.

Tuesday, a weak shortwave and surface front will drop south through
the forecast area. Expect a few showers and thunderstorms,
especially along/east of the Mississippi River. Temperatures will
warm into the 70s and 80s.

This warming trend will continue Wednesday and Thursday as the upper
level flow transitions from northwesterly to near zonal. A front is
expected to stall across the area Wednesday night through Thursday
night. Several synoptic models suggest a potential MCS moving into
the forecast area Wednesday night. Much of the CWA is outlooked in
the marginal risk category. Additional rounds of storms are possible
Thursday and Thursday night. Cape/shear/moisture profiles support
some additional severe threat, along with potential for heavy rain
through the period.

Friday is expected to be mainly dry and a bit cooler. Looking ahead
to next weekend, there is a loose model consensus on another
trough digging into the region with more rain and cooler temps.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
ISSUED AT 103 PM CDT Mon Jun 19 2017

Widely scattered showers and thunderstorms are expected over
eastern Iowa and northwest Illinois by mid afternoon. Coverage
looks too low to include in the terminal forecasts at this time.
Otherwise, VFR conditions will persist today through Tuesday
morning with gusty northwest winds becoming light and backing to
the west and then southwest overnight into Tuesday morning.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

$$

UPDATE...Sheets
SYNOPSIS...Haase
SHORT TERM...Haase
LONG TERM...RP Kinney
AVIATION...Sheets



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