997
FXUS63 KDVN 191146
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
646 AM CDT Sat Apr 19 2025

.KEY MESSAGES...

- Strong storm system will cross our area Easter Sunday and
  Sunday night, with widespread rainfall and perhaps severe
  storms

- Seasonal temperatures are expected this weekend, with a warm
  up next week

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 310 AM CDT Sat Apr 19 2025

Stalled frontal boundary from central MO to central IL will be
close enough to keep chance pops for showers in our far southern
counties through tonight. The remainder of the forecast area
will remain dry with more sunshine in our north compared to a
mostly cloudy sky in our south. Highs today will be mainly in
the upper 50s to lower 60s, with lows tonight ranging from the
upper 30s along Hwy 20 to the upper 40s south.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 310 AM CDT Sat Apr 19 2025

Sunday and Sunday night: A longwave upper-level trough is
expected to move out of the Rockies and approach our region for
Easter Sunday, becoming more negatively-tilted with time. A
potent mid-level vort max should pivot through the area,
supporting large-scale forcing for ascent. An attendant surface
low pressure system will lift northward from the southern Great
Plains towards eastern Iowa by Sunday evening. This will support
widespread rain (80-100% chance) and a few thunderstorms. Heavy
downpours at times will be the main story with this system, as
instability will be more limited. However, abundant moisture is
expected, with Pwat values progged around 1 to 1.5 inches, as
well as integrated water vapor transport per the ECWMF ensemble
percentiles giving values over 97% of climatology. NBM
exceedance probabilities of one inch of total rainfall for
Sunday through Sunday night range from 40 to 70% for most
locations, so at least an inch of total rainfall appears likely
across much of the forecast area.

Severe potential: SPC has shifted the Marginal Risk (level 1 of
5) for strong to severe storms a bit farther north up to almost
I-80. A Slight Risk (level 2 of 5) has also been introduced for
areas along and south of Highway 34. Even an Enhanced (3 of 5)
is not that far to the south of the forecast area. These
outlooks may be adjusted more so continue to monitor the latest
trends. The main threats as of now appear to be damaging wind,
large hail and a few tornadoes, with the greatest threat farther
to our south. CAM`s depict a bkn line of thunderstorms, possibly
some severe, quickly moving northeast across the forecast area
between 6 pm and midnight Sunday evening.

Monday through Friday: the pattern remains somewhat active
despite zonal flow aloft. Periodic shortwaves will translate
through the region, which could spark off some additional
showers and storms, but exact timing and location details remain
uncertain this far out. Temperatures are expected to gradually
warm up into the 70s for much of this time-frame.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 642 AM CDT Sat Apr 19 2025

VFR conds will be across all the taf sites with a northwest
wind around 10 kts, becoming northeast by 00z/20.

&&

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

&&

$$

SHORT TERM...Haase
LONG TERM...Haase
AVIATION...Haase