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fxus63 kdvn 190014 

Area forecast discussion
National Weather Service Quad Cities Iowa Illinois
614 PM CST Mon Nov 18 2019

..00z aviation update...

issued at 251 PM CST Mon Nov 18 2019

Mostly cloudy and cool across the region on Monday with weak high
pressure exiting into Illinois and Indiana. There were weak returns
on radar stretching from west central Illinois southwestward into
northern Missouri associated with a weak shortwave passing to our
south. Rain associated with a second shortwave forecast to move
across the area tonight was moving into north central Iowa.
Temperatures across the area this afternoon ranged from the lowers
30s at Dubuque to the lower 40s in far southeast Iowa. Dew points
were in the lower to mid 30s.


Short term...(this evening through tuesday)
issued at 251 PM CST Mon Nov 18 2019

The main forecast concerns were chances, and placement of
precipitation tonight. The ecwmf and Gem continue to show an overall
stronger wave with tonights storm system than the GFS and NAM but
are in good overall agreement.

Northwesterly flow aloft is continuing to bring a more active
pattern to the upper Midwest today through Tuesday. A weaker wave is
currently passing to our south this afternoon with weak radar
returns across far southeast Iowa and adjacent areas of west central
Illinois. Nothing appears to be reaching the ground. The ecwmf and
Gem have a stronger initial wave than the GFS and NAM which may be
leading to an overall increase in precipitation coverage across
eastern Iowa and northwest Illinois. The second wave forecast to
move across the area after 03 UTC tonight and exiting the area by 15
UTC on Tuesday. Have kept lower precipitation chances over far
southern Iowa and west central Illinois overnight as stronger
energy is associated the second wave and do not think that there
will be more widespread precipitation that far south given the model
soundings are not saturated and better moisture and lift are .
Positioned farther north. Model forecast soundings indicate that
precipitation should remain as all rain through the event with a
rain and snow mix possible in Stephenson and Jo Daviess County.
After low temperatures this evening, temperatures will gradually
warm overnight and into Tuesday ahead of a weak cold front that will
move across the area during the late morning and early afternoon.
Rainfall amounts should be less than an tenth of an inch.

Long term...(tuesday night through monday)
issued at 251 PM CST Mon Nov 18 2019

Key messages:

1.Warm temperatures to start the long term period before
a strong storm system is expected across the area.

2. Small chances for another system early into the weekend
may bring some snow to the area.

Temperatures are still expected to be in the 50s to 60s
Wednesday and Thursday across the area as strong warm air advection brings
in +8 to +10c across the area. The quick moving wave will
be out of sync with the larger feature to the north.
Nonetheless, a jet streak is expected to move south of the
area Thursday morning. The left exit region will be across
the area and will lead to better rising motion for our region.
In response to the wave and jet, strong directional and speed
shear will be available in the lowest levels. In fact shear
is conducive to rotation, if we can get a thunderstorm.
The question of cirrus is the main question with this system.
There is MUCAPE and very limited SBCAPE from 06z to 15z across
our area. Have not added thunder yet because not completely
confident in it occurring at this time. Later shifts will need to
keep an eye on this. Overall rainfall amounts look to range from
half an inch to one inch.

Into the weekend, temperatures will be cooler but near normals
across the region. There is another system form the beginning
of the weekend. The European model (ecmwf) is the one model that has the best
chance for precip across the area. The latest run has pushed
the bullseye south and east of the area than previously expected.


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 554 PM CST Mon Nov 18 2019

The taf cycle will start out predominantly VFR at the sites, with
the exception being dbq where MVFR ceilings will linger. In
general, anticipate a return of more widespread MVFR to IFR
conditions in low clouds, fog, and some rain or showers later
tonight into Tuesday morning ahead of a weak boundary. Drier air
on increasing west/northwest winds may bring some VFR conditions
via lifting of ceilings or scattering of clouds later Tuesday
afternoon at Cid, brl and possibly mli continuing beyond the end
of the period.


Dvn watches/warnings/advisories...


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