294
FXUS63 KDVN 072052
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
352 PM CDT Sun Jul 7 2024

.KEY MESSAGES...

- Active/unsettled through early week with periodic showers and
storms.

- Depending on the track, the remnants of tropical cyclone Beryl
could bring rain to far south/east portions of the service area
Tuesday night into Wednesday.

- Temperatures generally near normal through much of next week,
  followed by potential heat and humidity towards the weekend.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 202 PM CDT Sun Jul 7 2024

A broad upper low remains positioned over northern Minnesota this
afternoon, with a trof extending south through the Plains. Our area
remains in a very moist air mass, with weakly forced showers and
storms moving east/northeast at times. The morning activity has
slowly waned today, with a band of rain still falling from around
Fairfield to Tipton as of 1 PM. Under this rain/clouds, temperatures
have been held much lower today, in the upper 60s to lower 70s,
while outside of this cloud cover, we`ve warmed up strongly today
into the mid to upper 80s, setting up a convectively active boundary
from northeast Missouri to northern Illinois this afternoon.

This boundary has access to estimated 1500 CAPE and and 25-30 kts of
0-6km shear. This is sufficient for updraft tilt and some
spotty severe weather, primarily from wind gusts and quarter
size hail this afternoon. This activity should exit the CWA by
late afternoon, leaving the next round of forcing to spread
activity over the CWA tonight.

The next short wave is rounding the base of the upper trof today,
and will move northeast over Iowa and Illinois tonight. While models
are highly varied on location of any QPF with this feature, it does
look like an uptick in coverage of showers and storms will occur
tonight, with some training of storms as well. This repetitive
movement, will combine with PWAT values estimated around 1.70", to
bring isolated heavy rain totals over 1 inch again.

These rain amounts may influence river forecasts, as was see today
on the Cedar River at Cedar Rapids slight increase in
crest following the 1+" rain upstream of it last night.

Pops tonight are in the 50 to 75% range, given the increase in
evening and overnight storms with the short wave.

With clouds and dew points a step up from last night, lows in the
mid to upper 60s are expected tonight.


&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 202 PM CDT Sun Jul 7 2024

We continue with an unsettled/active early week period, as the
positively-tilted mid/upper level trough progresses eastward
toward the western Great Lakes by Tuesday. Through Tuesday
(mainly east) a series of shortwaves will continue to traverse
the region along the SW to NE oriented flow aloft. These
disturbances coupled with a SW LLJ and forcing along a slow
moving cold front will foster periodic showers and storms,
especially near and east of the Mississippi River. Locally
heavy rains are possible with any repeated or slow moving
activity, while the organized severe weather threat appears low.

Farther out/Beryl`s potential brush by our area...

The progression of the broad mid/upper level trough will play
a pivotal role in determining whether or not we see any rain
and potentially gusty winds from the remnants of TC Beryl
Tuesday night into Wednesday. The latest forecast from NHC and
super ensemble mean track would take the remnant low from south
of St Louis to northwest Ohio Wednesday into Thursday. The
surface low tracks from the operational GFS, GEFS mean, and
several members of ECMWF ensemble however, show a track further
north/west, and closer to the western edge of the NHC forecast
cone into northwest Illinois (not something we`re used to
seeing!). To try and account for some potential of a more
north/west track we`ve collaborated with eastern neighboring
offices blending in some CONSAll guidance with NBM to give PoPs
a bit of an increase across far SE portions of the service area
Tuesday night into Wednesday, although staying in the chance
(30-40%) category for now. We`ll continue to monitor the track
of Beryl closely in the next 48+ hours, so stay tuned for
updates.

Heading into late next week and next weekend, the ensemble
guidance supports ridging across the Intermountain West and
Mid-Atlantic with weak troughing from the western Great Lakes
to the Lower Mississippi Valley. This will keep some chances
for precipitation, although nothing too widespread/organized and
perhaps more isolated diurnally driven. Temperatures should
remain near normal into late next week, but by next weekend and
just beyond there are some signs that the western ridge /heat
dome/ may try to build toward the region leading to greater
summer heat potential.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1225 PM CDT Sun Jul 7 2024

VFR conditions will largely dominate, but there will be scattered
shra/tsra throughout the TAF period accompanied by MVFR to IFR
conditions (mainly for visibility). Outside of outflow near
storms winds will generally be light from a southerly direction.
The main period where showers and storms appear possible is
during the late evening and overnight hours, after which, a
period of MVFR cigs is more likely (50-70%).

&&

.HYDROLOGY...
Issued at 1225 PM CDT Sun Jul 7 2024

The Mississippi River is currently cresting at and upstream of
Camanche, IA. The crest may take 1 to as much as 3 days to pass.
From Le Claire to Burlington, the respective crests will commence
within the next 1 to 2 days.

Keokuk is now forecast to crest within Moderate Flood category
beginning Friday.  The crest at Gregory Landing is forecast late
Friday into Saturday.

Tributary Rivers:

Heavier rainfall overnight of near an inch upstream of Cedar Rapids
has resulted in a slightly higher forecast for the Cedar River at
Cedar Rapids. The Watch has been upgraded to a Warning for minor
flooding with a forecast crest near 12.2 feet Monday evening.

On the Wapsipinicon River at Dewitt, it is near crest around 11.8
feet.  It is forecast to remain in moderate flooding category
through late on Friday.

On the Cedar River at Conesville, minor flooding will continue. It
will see a secondary crest near 14.6 feet Wednesday night into
Thursday.

The Iowa River at Oakville is seeing high water levels due to
backwater affects from the Mississippi River. It is forecast to
remain near 11.7 or 11.8 feet through midweek and then rise to near
12.1 feet late Thursday into Friday.

&&

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

&&

$$

SHORT TERM...Ervin
LONG TERM...McClure/Ervin
AVIATION...Ervin
HYDROLOGY...14